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Sample records for battery dc bus

  1. A Distributed Control Strategy Based on DC Bus Signaling for Modular Photovoltaic Generation Systems With Battery Energy Storage

    DEFF Research Database (Denmark)

    Sun, Kai; Zhang, Li; Xing, Yan;

    2011-01-01

    charging/discharging and local loads, which is available of either grid-connected operation or islanding operation. By using the proposed control strategy, the operations of a modular PV generation system are categorized into four modes: islanding with battery discharging, grid-connected rectification...... and maximum power point tracking operation, which enables the dc bus voltage regulation capability ofmodular dc/dc converters. Seamless switching of a battery converter between charging and discharging and that of a grid-connected converter between rectification and inversion are ensured by the proposed...

  2. Overview of Multi-DC-Bus Solutions for DC Microgrids

    DEFF Research Database (Denmark)

    Ricchiuto, D.; Mastromauro, R.A.; Liserre, Marco;

    2013-01-01

    DC Microgrids have recently received a lot of attention in the last years due to high penetration of renewable energy sources as well as distributed energy storage systems. In the future DC microgrids could be preferable respect to AC microgrids in terms of redundancy since multi-DC-Bus solutions...

  3. A High Efficiency DC Bus Regulator / RPC for Spacecraft Applications

    Science.gov (United States)

    Birchenough, Arthur G.

    2004-02-01

    DC bus voltage regulation may be required in future high powered spacecraft due to the length of the busses or because they are not generated at precise voltage levels. In these cases the regulation range is often only a few percent increase or decrease, but conventional DC voltage regulators switch all the power passing through them, and this level of power switched determines the size and losses in the regulator. A recently developed concept uses a low power DC-DC converter in series with the bus to raise or lower the bus voltage over a small range. This partial power processing technique combines the small size and power losses of the low power converter with the ability to regulate, (over a small range) a high power bus. The Series Connected Buck Boost Regulator (SCBBR) described herein provides bus regulation with an efficiency of 98%. The circuit also provides bus switching and overcurrent limiting functions of a Remote Power Controller (RPC). This paper describes the circuit design and performance of a breadboard SCBBR configured as a bus voltage regulator providing +/- 40% voltage regulation range, bus switching, and overload limiting.

  4. Directly connected series coupled HTPEM fuel cell stacks to a Li-ion battery DC bus for a fuel cell electrical vehicle

    DEFF Research Database (Denmark)

    Andreasen, Søren Juhl; Ashworth, Leanne; Remón, Ian Natanael;

    2008-01-01

    The work presented in this paper examines the use of pure hydrogen fuelled high temperature polymer electrolyte membrane (HTPEM) fuel cell stacks in an electrical car, charging a Li-ion battery pack. The car is equipped with two branches of two series coupled 1 kW fuel cell stacks which...... are connected directly parallel to the battery pack during operation. This enables efficient charging of the batteries for increased driving range. With no power electronics used, the fuel cell stacks follow the battery pack voltage, and charge the batteries passively. This saves the electrical and economical...... losses related to these components and their added system complexity. The new car battery pack consists of 23 Li-ion battery cells and the charging and discharging are monitored by a battery management system (BMS) which ensures safe operating conditions for the batteries. The direct connection...

  5. Charge pump DC-DC converter comprising solid state batteries

    NARCIS (Netherlands)

    Reefman, D.; Roozeboom, F.; Notten, P.H.L.; Klootwijk, J.H.

    2013-01-01

    An electronic device is provided which comprises a DC-DC converter. The DC-DC converter comprises at least one solid-state rechargeable battery (B1, B2) for storing energy for the DC-DC conversion and an output capacitor (C2).

  6. Damping torque analysis for DC bus implemented damping control

    OpenAIRE

    W. Du; WANG, HAIFENG; Ju, P.; Dunn, R

    2010-01-01

    Damping torque analysis is a well-developed technique for understanding and studying power system oscillations. This paper presents the applications of damping torque analysis for DC bus implemented damping control in power transmission networks in two examples. The first example is the investigation of damping effect of shunt VSC (Voltage Source Converter) based FACTS voltage control, i.e., STATCOM (Static Synchronous Compensator) voltage control. It is shown in the paper that STATCOM voltag...

  7. An Electric Bus with a Battery Exchange System

    Directory of Open Access Journals (Sweden)

    Jeongyong Kim

    2015-07-01

    Full Text Available As part of the ongoing effort to be independent of petroleum resources and to be free from pollutant emission issues, various electric vehicles have been developed and tested through their integration with real world systems. In the current paper, yet another application specific EV for public transportation, an electric bus, is introduced and explained with results from the pilot test program which was carried out under real traffic conditions. The main feature of the current system is a battery exchanging mechanism mounted on the roof of the bus. The current configuration certainly requires an externally fabricated battery exchanging robot system that would complement the electric bus for a fully automated battery exchanging process. The major advantage of the current system is the quick re-charging of the electric energy through the physical battery exchange and the possible utilization of the battery exchange station as a mini scale energy storage system for grid system peak power shaving. With the total system solution approach for the public transportation system, it is fully expected to create outstanding business opportunities in number of areas such as battery suppliers, battery exchanging station management, battery leasing and many more.

  8. Hybrid battery with bi-directional DC/DC converter

    Directory of Open Access Journals (Sweden)

    DUDRIK Jaroslav

    2010-05-01

    Full Text Available Bi-directional buck-boost DC/DC converterfor hybrid battery is described in this paper. The firstpart of the paper is aimed at concept of hybrid battery;main advance compared to conventional accumulatoris explained there. Control circuit with UC3637 andpower circuit of the converter are described in thesecond part of the paper. Experimental results frommeasuring of converter are mentioned in the last part.

  9. Hybrid battery with bi-directional DC/DC converter

    OpenAIRE

    DUDRIK Jaroslav; OLEJAR Martin; BERES Tomáš

    2010-01-01

    Bi-directional buck-boost DC/DC converterfor hybrid battery is described in this paper. The firstpart of the paper is aimed at concept of hybrid battery;main advance compared to conventional accumulatoris explained there. Control circuit with UC3637 andpower circuit of the converter are described in thesecond part of the paper. Experimental results frommeasuring of converter are mentioned in the last part.

  10. DC Bus Regulation with a Flywheel Energy Storage System

    Science.gov (United States)

    Kenny, Barbara H.; Kascak, Peter E.

    2003-01-01

    This paper describes the DC bus regulation control algorithm for the NASA flywheel energy storage system during charge, charge reduction and discharge modes of operation. The algorithm was experimentally verified with results given in a previous paper. This paper presents the necessary models for simulation with detailed block diagrams of the controller algorithm. It is shown that the flywheel system and the controller can be modeled in three levels of detail depending on the type of analysis required. The three models are explained and then compared using simulation results.

  11. Foothill Transit Battery Electric Bus Demonstration Results

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Prohaska, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kelly, Kenneth [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-01-27

    Foothill Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL) to evaluate its fleet of Proterra battery electric buses (BEBs) in revenue service. The focus of this evaluation is to compare performance of the BEBs to that of conventional technology and to track progress over time toward meeting performance targets. This project has also provided an opportunity for DOE to conduct a detailed evaluation of the BEBs and charging infrastructure. This report provides data on the buses from April 2014 through July 2015. Data are provided on a selection of compressed natural gas buses as a baseline comparison.

  12. Charger for NiMH batteries based on buck DC/DC converter

    OpenAIRE

    Lapčević Vladimir

    2014-01-01

    In this paper is presented charger for NiMH battery types AA. Charger is realized by Buck DC/DC converter and microcontroller. Microcontroller controls the work of Buck DC/DC converter by pulse width modulation and by measuring the current of battery charging. The current of charging is held constant by power electronics, and the time of charging is set by the user dependent of capacity of the battery. Standard battery chargers enable the recharge of NiMH b...

  13. An Higher Case Operation and Analysis of a Multiple Renewable Resources Connected To A Dc Load Through Dc Bus

    Directory of Open Access Journals (Sweden)

    G. Mahesh Kumar

    2014-08-01

    Full Text Available In our nation the usage of electricity is increasing day-by-day. According to that conserdations, the generated power from the non-renewable sources will not satisfy the demands properly. so for these purpose, by using multiple renewable sources, it will be very useful to some type of dc applications. The power produced from the individual renewable sources will not be satisfy the demand at all times. So by integration of a multiple renewable sources such as wind and solar a huge amount of power will be produced. These power will be coordinated to the ac grid or directly to dc consumers. For integration of renewable sources an aggregated model has to be proposed. In according to these operation BESS (battery energy storage systemis equipped with the system for maintaining the power balance. For obtaining the power balance the adaptive droop control technique has to be proposed and droop curves are evaluated. The droop characteristics are selected on the basis of the deviation between the optimized and real-time SOC of the BESS. In these paper, the operational analysis can be performed when real time soc is higher than the optimised soc and droop curves are plotted. Operational controls with in the micro grid [such as cost have to be optimized at the same time it will satisfy the demand] are designed to support the integration of wind and solar power. By these process micro grid real time supply and demand will be maintain in symmetry. The simulation results are to be developed in MATLAB SIMULINK process for renewable power generation and fast charging load connected to the dc bus, droop control based responses.

  14. Hybrid electric system based on fuel cell and battery and integrating a single dc/dc converter for a tramway

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Luis M., E-mail: luis.fernandez@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Pablo, E-mail: pablo.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Carlos Andres, E-mail: carlosandres.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Jurado, Francisco, E-mail: fjurado@ujaen.e [Department of Electrical Engineering, EPS Linares, University of Jaen, C/Alfonso X, No. 28. 23700 Linares (Jaen) (Spain)

    2011-05-15

    Research highlights: {yields} Hybrid electric power system for a real surface tramway. {yields} Hybrid system based on PEM fuel cell with dc/dc converter and Ni-MH battery. {yields} New control strategy for the energy management of the tramway. {yields} Hybrid system demonstrated to meet appropriate driving cycle of the tramway. -- Abstract: This paper presents a hybrid electric power system for a real surface tramway. The hybrid system consists of two electrical energy sources integrating a single dc/dc converter to provide the power demanded by the tramway loads (four electric traction motors and auxiliary services): (1) a Polymer Electrolyte Membrane (PEM) fuel cell (FC) as the primary and (2) a rechargeable Ni-MH battery as electrical energy storage to supplement the FC over the driving cycle. According to the requirements of the real driving cycle of the tramway, it was considered a 200 kW PEM FC system with two FCs connected in parallel and a 34 Ah Ni-MH battery. The PEM FC and Ni-MH battery models were designed from commercially available components. The power conditioning system provides the appropriate power for the tramway. It is composed of: (1) a unique dc/dc boot converter which adapts the FC output voltage to the 750 V traction standard dc bus; (2) three phase inverters to drive properly each electric motors; and (3) a braking chopper to dissipate excess of regenerative braking energy. Suitable state machine control architecture is presented for the hybrid system, its objective being to provide demanded power by the driving cycle, optimizing the energy generated. Following this objective, a new state machine control strategy based on eight states decides the operating point of each component of the system and a cascade control structure allows achieving the operating points determined by the strategy. Simulation results of the real driving cycle of the tramway check the adequacy of the hybrid electric power system.

  15. Converter Power Density Increase using Low Inductive Integrated DC-link Capacitor/Bus

    DEFF Research Database (Denmark)

    Trintis, Ionut; Franke, Toke; Rannested, Bjørn;

    2015-01-01

    The power losses in switching devices have a direct effect on the maximum converter power. For a voltage source converter, the DC-link bus has a major influence on the power loss and safe operating area of the power devices. The Power Ring Film CapacitorTM integrated with an optimized bus structu...... has a measured inductance of around 5 nH. That allows the converter to switch with low turn-off losses, and allows the safe operation at higher dc-link voltages. This paper investigates the power transfer limits of a ShowerPower® cooled power stack....

  16. Supervisory Control of an Adaptive-Droop Regulated DC Microgrid with Battery Management Capability

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Guerrero, Josep M.; Vasquez, Juan Carlos;

    2014-01-01

    tracking (MPPT) for renewable energy sources (RESs), with which a smooth on-line overlap was designed; 2) the supervisory control layer was designed to use the low bandwidth communication interface between the central controller and sources in order to collect data needed for adaptive calculation......DC power systems are gaining an increasing interest in renewable energy applications because of the good matching with dc output type sources such as photovoltaic (PV) systems and secondary batteries. In this paper, several distributed generators (DGs) have been merged together with a pair...... voltage-droop (VD) method aimed to regulate the common bus voltage and to sustain the states of charge (SOCs) of batteries close to each other during moderate replenishment. The control of every unit was expanded with unit-specific algorithm, i.e. finish-of-charging for batteries and maximum power point...

  17. Extracting DC bus current information for optimal phase correction and current ripple in sensorless brushless DC motor drive

    Institute of Scientific and Technical Information of China (English)

    Zu-sheng HO; Chii-maw UANG; Ping-chieh WANG

    2014-01-01

    Brushless DC motor (BLDCM) sensorless driving technology is becoming increasingly established. However, op-timal phase correction still relies on complex calculations or algorithms. In finding the correct commutation point, the problem of phase lag is introduced. In this paper, we extract DC bus current information for auto-calibrating the phase shift to obtain the correct commutation point and optimize the control of BLDC sensorless driving. As we capture only DC bus current information, the original shunt resistor is used in the BLDCM driver and there is no need to add further current sensor components. Software processing using only simple arithmetic operations successfully accomplishes the phase correction. Experimental results show that the proposed method can operate accurately and stably at low or high speed, with light or heavy load, and is suitable for practical applications. This approach will not increase cost but will achieve the best performance/cost ratio and meet market expectations.

  18. Geometric-Process-Based Battery Management Optimizing Policy for the Electric Bus

    Directory of Open Access Journals (Sweden)

    Yan Li

    2015-01-01

    Full Text Available With the rapid development of the electric vehicle industry and promotive policies worldwide, the electric bus (E-bus has been adopted in many major cities around the world. One of the most important factors that restrain the widespread application of the E-bus is the high operating cost due to the deficient battery management. This paper proposes a geometric-process-based (GP-based battery management optimizing policy which aims to minimize the average cost of the operation on the premise of meeting the required sufficient battery availability. Considering the deterioration of the battery after repeated charging and discharging, this paper constructs the model of the operation of the E-bus battery as a geometric process, and the premaintenance time has been considered with the failure repairment time to enhance the GP-based battery operation model considering the battery cannot be as good as new after the two processes. The computer simulation is carried out by adopting the proposed optimizing policy, and the result verifies the effectiveness of the policy, denoting its significant performance on the application of the E-bus battery management.

  19. An Improved Droop Control Method for DC Microgrids Based on Low Bandwidth Communication with DC Bus Voltage Restoration and Enhanced Current Sharing Accuracy

    DEFF Research Database (Denmark)

    Lu, Xiaonan; Guerrero, Josep M.; Sun, Kai;

    2014-01-01

    resistance in a droop-controlled dc microgrid, since the output voltage of each converter cannot be exactly the same, the output current sharing accuracy is degraded. Second, the DC bus voltage deviation increases with the load due to the droop action. In this paper, in order to improve the performance...... information between converter units. The droop controller is employed to achieve independent operation and average voltage and current controllers are used in each converter to simultaneously enhance the current sharing accuracy and restore the dc bus voltage. All of the controllers are realized locally...

  20. Distributed Bus Signaling Control for a DC Charging Station with Multi Paralleled Flywheel Energy Storage System

    DEFF Research Database (Denmark)

    Sun, Bo; Dragicevic, Tomislav; Vasquez, Juan Carlos;

    2015-01-01

    Fast charging stations (FCS) will become an essential part of future transportation systems with an increasing number of electrical vehicles. However, since these FCS plugs have power ratings of up to 100 kW, serious stress caused by large number of FCS could threaten the stability of the main...... power grid. To overcome the possible adverse impacts, this paper applies a dedicated paralleled flywheels energy storage system (ESS) in FCS, to balance the power by the method of ramping the initial power peak. Distributed DC-bus signaling (DBS) method is employed in the power coordination of grid...

  1. An Electric Bus with a Battery Exchange System

    OpenAIRE

    Jeongyong Kim; Inho Song; Woongchul Choi

    2015-01-01

    As part of the ongoing effort to be independent of petroleum resources and to be free from pollutant emission issues, various electric vehicles have been developed and tested through their integration with real world systems. In the current paper, yet another application specific EV for public transportation, an electric bus, is introduced and explained with results from the pilot test program which was carried out under real traffic conditions. The main feature of the current system is a bat...

  2. Minimizing heat loss in DC networks using batteries

    CERN Document Server

    Zocca, Alessandro

    2016-01-01

    Electricity transmission networks dissipate a non-negligible fraction of the power they transport due to the heat loss in the transmission lines. In this work we explore how the transport of energy can be more efficient by adding to the network multiple batteries that can coordinate their operations. Such batteries can both charge using the current excess in the network or discharge to meet the network current demand. Either way, the presence of batteries in the network can be leveraged to mitigate the intrinsic uncertainty in the power generation and demand and, hence, transport the energy more efficiently through the network. We consider a resistive DC network with stochastic external current injections or consumptions and show how the expected total heat loss depends on the network structure and on the batteries operations. Furthermore, in the case where the external currents are modeled by Ornstein-Uhlenbeck processes, we derive the dynamical optimal control for the batteries over a finite time interval.

  3. Research, development and demonstration of a fuel cell/battery powered bus system. Phase 1, Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-02-28

    Purpose of the Phase I effort was to demonstrate feasibility of the fuel cell/battery system for powering a small bus (under 30 ft or 9 m) on an urban bus route. A brassboard powerplant was specified, designed, fabricated, and tested to demonstrate feasibility in the laboratory. The proof-of-concept bus, with a powerplant scaled up from the brassboard, will be demonstrated under Phase II.

  4. Integrated Three-Port DC-DC Converter for Photovoltaic (PV) Battery Stand-alone Systems

    DEFF Research Database (Denmark)

    Ouyang, Ziwei; Andersen, Michael A. E.

    2016-01-01

    Several power sources such as PV solar arrays and battery are often used to manage the power flow for a photovoltaic (PV) based stand-alone power system due to the fluctuation nature of solar energy resource, and deliver a continuous power to the users in an appropriate form. Traditionally, three...... different single-input single-output (SISO) dc/dc converters would have been used. To reduce the cost and improve the power density of the system, an integrated three-port isolated dc/dc converter is proposed in this paper. It can realize all functions of the energy delivery due to the fluctuation nature...... for PV and battery stand-alone system....

  5. Soft switching bidirectional DC-DC converter for ultracapacitor-batteries interface

    Energy Technology Data Exchange (ETDEWEB)

    Adib, Ehsan; Farzanehfard, Hosein [Dept. of Electrical and Computer Engineering, Isfahan Univ. of Technology (Iran)

    2009-12-15

    In this paper a new soft switching bidirectional DC-DC converter is introduced which can be applied as the interface circuit between ultracapacitors and batteries or fuel cells. All semiconductor devices in the proposed converter are soft switched while the control circuit remains PWM. Due to achieved soft switching condition, the energy conversion through the proposed converter is highly efficient. The proposed converter is analyzed and a prototype converter is implemented. The presented experimental results confirm the theoretical analysis. (author)

  6. Optimal vehicle control strategy of a fuel cell/battery hybrid city bus

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Liangfei; Li, Jianqiu; Hua, Jianfeng; Li, Xiangjun; Ouyang, Minggao [State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084 (China)

    2009-09-15

    In this article, an optimal vehicle control strategy based on a time-triggered controller area network (TTCAN) system for a polymer electrolyte membrane (PEM) fuel cell/nickel-metal hydride (Ni-MH) battery powered city bus is presented. Aiming at improving the fuel economy of the city bus, the control strategy comprises an equivalent consumption minimization strategy (ECMS) and a braking energy regeneration strategy (BERS). On the basis of the introduction of a battery equivalent hydrogen consumption model incorporating a charge-sustaining coefficient, an analytical solution to the equivalent consumption minimization problem is given. The proposed strategy has been applied in several city buses for the Beijing Olympic Games of 2008. Results of the ''China city bus typical cycle'' testing show that, the ECMS and the BERS lowered hydrogen consumption by 2.5% and 15.3% respectively, compared with a rule-based strategy. The BERS contributes much more than the ECMS to the fuel economy, because the fuel cell system does not leave much room for the optimal algorithm in improving the efficiency. (author)

  7. Increased Energy Delivery for Parallel Battery Packs with No Regulated Bus

    Science.gov (United States)

    Hsu, Chung-Ti

    In this dissertation, a new approach to paralleling different battery types is presented. A method for controlling charging/discharging of different battery packs by using low-cost bi-directional switches instead of DC-DC converters is proposed. The proposed system architecture, algorithms, and control techniques allow batteries with different chemistry, voltage, and SOC to be properly charged and discharged in parallel without causing safety problems. The physical design and cost for the energy management system is substantially reduced. Additionally, specific types of failures in the maximum power point tracking (MPPT) in a photovoltaic (PV) system when tracking only the load current of a DC-DC converter are analyzed. The periodic nonlinear load current will lead MPPT realized by the conventional perturb and observe (P&O) algorithm to be problematic. A modified MPPT algorithm is proposed and it still only requires typically measured signals, yet is suitable for both linear and periodic nonlinear loads. Moreover, for a modular DC-DC converter using several converters in parallel, the input power from PV panels is processed and distributed at the module level. Methods for properly implementing distributed MPPT are studied. A new approach to efficient MPPT under partial shading conditions is presented. The power stage architecture achieves fast input current change rate by combining a current-adjustable converter with a few converters operating at a constant current.

  8. Time delay control for fuel cells with bidirectional DC/DC converter and battery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y.B. [Mechanical Engineering Department, Chonnam National University, Gwangju (Korea); Kang, S.J. [Mechatronics Engineering Department, Korea Polytechnic College V, Gwangju (Korea)

    2010-08-15

    Transient behavior is a key property in the vehicular application of proton exchange membrane (PEM) fuel cells. A better control technology is constructed to increase the transient performance of PEM fuel cells. A steady-state isothermal analytical fuel cell model is constructed to analyze mass transfer and water transport in the membrane. To prevent the starvation of air in the PEM fuel cell, time delay control is used to regulate the optimum stoichiometric amount of oxygen, although dynamic fluctuations exist in the PEM fuel cell power. A bidirectional DC/DC converter connects the battery to the DC link to manage the power distribution between the fuel cell and the battery. Dynamic evolution control (DEC) allows for adequate pulse-width modulation (PWM) control of the bidirectional DC/DC converter with fast response. Matlab/Simulink/Simpower simulation is performed to validate the proposed methodology, increase the transient performance of the PEM fuel cell system and satisfy the requirement of energy management. (author)

  9. Control of a three-phase four-wire shunt-active power filter based on DC-bus energy regulation

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Teodorescu, Remus; Rodriguez, Pedro;

    2008-01-01

    stored in the DC bus and active power requirements on the APF. Harmonics and imbalances both on the utility voltage and load current have been considered and the power developed by the active power filter has been evaluated. This study allows designing a controller for the APF based on the regulation...... of the energy-state of its DC-bus. The method has been experimentally tested on a four leg APF based on a neutral-point-clamped DC bus. Such topology allowed the test of the most general case, including harmonics and imbalance in utility voltage and in load currents....

  10. Advanced dc motor controller for battery-powered electric vehicles

    Science.gov (United States)

    Belsterling, C. A.

    1981-01-01

    A motor generation set is connected to run from the dc source and generate a voltage in the traction motor armature circuit that normally opposes the source voltage. The functional feasibility of the concept is demonstrated with tests on a Proof of Principle System. An analog computer simulation is developed, validated with the results of the tests, applied to predict the performance of a full scale Functional Model dc Controller. The results indicate high efficiencies over wide operating ranges and exceptional recovery of regenerated energy. The new machine integrates both motor and generator on a single two bearing shaft. The control strategy produces a controlled bidirectional plus or minus 48 volts dc output from the generator permitting full control of a 96 volt dc traction motor from a 48 volt battery, was designed to control a 20 hp traction motor. The controller weighs 63.5 kg (140 lb.) and has a peak efficiency of 90% in random driving modes and 96% during the SAE J 227a/D driving cycle.

  11. Experimental Results of a DC Bus Voltage Level Control for a Load-Controlled Marine Current Energy Converter

    Directory of Open Access Journals (Sweden)

    Johan Forslund

    2015-05-01

    Full Text Available This paper investigates three load control methods for a  marine current energy converter using a vertical axis current  turbine (VACT mounted on a permanent magnet synchronous generator  (PMSG. The three cases are; a fixed AC load, a fixed pulse width  modulated (PWM DC load and DC bus voltage control of a DC  load. Experimental results show that the DC bus voltage control  reduces the variations of rotational speed by a factor of 3.5 at the cost  of slightly increased losses in the generator and transmission lines.  For all three cases, the tip speed ratio \\(\\lambda\\ can be kept close to  the expected \\(\\lambda_{opt}\\. The power coefficient is estimated to be  0.36 at \\(\\lambda_{opt}\\; however, for all three cases, the average  extracted power was about \\(\\sim 19\\\\%. A maximum power point  tracking (MPPT system, with or without water velocity measurement,  could increase the average extracted power.

  12. A bi-directional DC/DC converter for hybrid wind generator/battery system with state machine control

    Energy Technology Data Exchange (ETDEWEB)

    Hua, C.C.; Liao, Y.C. [National Yunlin Univ. of Science and Technology, Yunlin, Taiwan (China). Dept. of Electrical Engineering

    2008-07-01

    A bi-directional DC to DC converter used in a hybrid wind generator/lead-acid battery power system was presented. A state machine control strategy was used to control both the system power flow and load distribution. It was also used to increase the power capacity of the system. The battery was also charged or discharged through the bi-directional DC to DC converter. Multi-stage current charging control of the batteries was accomplished by adjusting the duty cycle of the power converter. This also improved the charging efficiency by the maximum power point tracking algorithm. It was concluded that the proposed control method can be readily extended to other renewable energy conversion systems. 6 refs., 13 figs.

  13. High-frequency modelling of a three-phase pulse width modulation inverter towards the dc bus considering line and controller harmonics

    Directory of Open Access Journals (Sweden)

    Saeid Haghbin

    2014-10-01

    Full Text Available Closed-form analytical formulas are provided to calculate the dc bus harmonics of a three-phase sinusoidal pulse width modulation (SPWM inverter. The harmonic analysis is performed by using a double Fourier series approach to determine the dc bus current frequency spectrum. For an arbitrary modulation index and load power factor, the full harmonic components of the inverter dc side current are calculated. Based on the developed analytical model, an equivalent circuit is proposed for the inverter harmonic analysis towards the dc bus. Moreover, the impacts of line harmonics and zero sequence injection in controller towards the dc bus are presented. The results show that the 5th and 7th ac line harmonics on the dc side current is appearance of the 6th harmonic in the dc side. The impact of zero sequence injection to the controller on the dc side is negligible. In addition to analytical formulation, different simulations and extensive measurements performed which the results verified the presented analytical framework.

  14. Battery Management System—Balancing Modularization Based on a Single Switched Capacitor and Bi-Directional DC/DC Converter with the Auxiliary Battery

    Directory of Open Access Journals (Sweden)

    Mohamed Daowd

    2014-04-01

    Full Text Available Lithium-based batteries are considered as the most advanced batteries technology, which can be designed for high energy or high power storage systems. However, the battery cells are never fully identical due to the fabrication process, surrounding environment factors and differences between the cells tend to grow if no measures are taken. In order to have a high performance battery system, the battery cells should be continuously balanced for maintain the variation between the cells as small as possible. Without an appropriate balancing system, the individual cell voltages will differ over time and battery system capacity will decrease quickly. These issues will limit the electric range of the electric vehicle (EV and some cells will undergo higher stress, whereby the cycle life of these cells will be shorter. Quite a lot of cell balancing/equalization topologies have been previously proposed. These balancing topologies can be categorized into passive and active balancing. Active topologies are categorized according to the active element used for storing the energy such as capacitor and/or inductive component as well as controlling switches or converters. This paper proposes an intelligent battery management system (BMS including a battery pack charging and discharging control with a battery pack thermal management system. The BMS user input/output interfacing. The battery balancing system is based on battery pack modularization architecture. The proposed modularized balancing system has different equalization systems that operate inside and outside the modules. Innovative single switched capacitor (SSC control strategy is proposed to balance between the battery cells in the module (inside module balancing, IMB. Novel utilization of isolated bidirectional DC/DC converter (IBC is proposed to balance between the modules with the aid of the EV auxiliary battery (AB. Finally an experimental step-up has been implemented for the validation of the

  15. An Interleaved Reduced-Component-Count Multivoltage Bus DC/DC Converter for Fuel Cell Powered Electric Vehicle Applications

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Lixin [ORNL; Su, Gui-Jia [ORNL

    2008-01-01

    An interleaved reduced-component-count dc/dc converter is proposed for power management in fuel cell powered vehicles with a multivoltage electric net. The converter is based on a simplified topology and can handle more power with less ripple current, therefore reducing the capacitor requirements, making it more suited for fuel cell powered vehicles in the near future. A prototype rated at 4.3 kW was built and tested to verify the proposed topology.

  16. Coordinated Control Based on Bus-Signaling and Virtual Inertia for Islanded DC Microgrids

    DEFF Research Database (Denmark)

    Wu, Dan; Tang, Fen; Dragicevic, Tomislav;

    2015-01-01

    A low-voltage DC islanded microgrid contains a number of renewable energy sources (RES), local loads, and energy storage systems (ESS). To avoid the over-charging and over-discharging situations of ESS, a coordinated control strategy should be used in DC islanded microgrids. In this paper, a novel...

  17. Multi-Purpose Low Voltage Dual Output DC-DC Converter For 100V Power Bus Telecom Platform

    Science.gov (United States)

    Galiana, D.; Mollard, J. M.

    2011-10-01

    The decreasing supply voltages of digital electronic and high speed ADC (Analog to Digital Converter) and DAC (Digital to Analog Converter) require flexible and high current secondary power distribution system. In the frame of the Inmarsat I-XL program, a 12 kW geomobile SatCom satellite, with 100 V regulated power bus, a multi purpose dual output converter was developed for the payload processor as a building block. After a short introduction on the main performance requirements, the baseline architecture is presented. The main drivers of the architecture are reliability, adjustability, radiation tolerant and single event free, volume and mass. The combination of all these constraints highlights the need of significant breakthrough in various domains. Many research results related to packaging and power electronic topics are brought up. These results directly drive the adopted solution presented in the next step followed by a description of the integration of the defined building block in the Inmarsat I-XL payload IP (Integrated Processor). Finally, the main electrical performances such as output ripple and spikes, load step transient and stability are summarized.

  18. DC-bus voltage control of grid-connected voltage source converter by using space vector modulated direct power control under unbalanced network conditions

    DEFF Research Database (Denmark)

    Xiao, Lei; Huang, Shoudao; Lu, Kaiyuan

    2013-01-01

    Unbalanced grid voltage will cause large dc-bus voltage ripple and introduce high harmonic current components on the grid side. This will severely threaten the safety of the grid-connected voltage source converter (VSC) and consequently, affect the healthy operation condition of the load. In this......Unbalanced grid voltage will cause large dc-bus voltage ripple and introduce high harmonic current components on the grid side. This will severely threaten the safety of the grid-connected voltage source converter (VSC) and consequently, affect the healthy operation condition of the load....... In this study, a new proportional-integral-resonant (PI-RES) controller-based, space vector modulated direct power control topology is proposed to suppress the dc-bus voltage ripple and in the same time, controlling effectively the instantaneous power of the VSC. A special ac reactive power reference component...... is introduced in the controller, which is necessary in order to reduce the dc-bus voltage ripple and active power harmonics at the same time. The proposed control topology is implemented in the lab. Simulation and experimental results are provided to validate its performance and the analysis presented...

  19. Solar photovoltaic charging of high voltage nickel metal hydride batteries using DC power conversion

    Science.gov (United States)

    Kelly, Nelson A.; Gibson, Thomas L.

    There are an increasing number of vehicle choices available that utilize batteries and electric motors to reduce tailpipe emissions and increase fuel economy. The eventual production of electricity and hydrogen in a renewable fashion, such as using solar energy, can achieve the long-term vision of having no tailpipe environmental impact, as well as eliminating the dependence of the transportation sector on dwindling supplies of petroleum for its energy. In this report we will demonstrate the solar-powered charging of the high-voltage nickel-metal hydride (NiMH) battery used in the GM 2-mode hybrid system. In previous studies we have used low-voltage solar modules to produce hydrogen via the electrolysis of water and to directly charge lithium-ion battery modules. Our strategy in the present work was to boost low-voltage PV voltage to over 300 V using DC-DC converters in order to charge the high-voltage NiMH battery, and to regulate the battery charging using software to program the electronic control unit supplied with the battery pack. A protocol for high-voltage battery charging was developed, and the solar to battery charging efficiency was measured under a variety of conditions. We believe this is the first time such high-voltage batteries have been charged using solar energy in order to prove the concept of efficient, solar-powered charging for battery-electric vehicles.

  20. Digital Simulation of Closed Loop Zvs-Zcs Bidirectional Dc-Dc Converter for Fuel Cell and Battery Application

    OpenAIRE

    V. V. Subrahmanya Kumar Bhajana; S. Rama Reddy

    2010-01-01

    A closed loop ZVS-ZCS bidirectional dc-dc converter is modeled and appropriate digital simulations are provided. With the ZVS-ZCS concept, the MATLAB simulation results of application to a fuel cell and battery application have been obtained whenever the input voltage exceeds the given 24V, at that time the load voltage will change from 180V to 230V. But due to this usage the load is disturbed and there is instability in the model. Using closed loop the output voltage is stabilized.

  1. Digital Simulation of Closed Loop Zvs-Zcs Bidirectional Dc-Dc Converter for Fuel Cell and Battery Application

    Directory of Open Access Journals (Sweden)

    V. V. Subrahmanya Kumar Bhajana

    2010-08-01

    Full Text Available A closed loop ZVS-ZCS bidirectional dc-dc converter is modeled and appropriate digital simulations are provided. With the ZVS-ZCS concept, the MATLAB simulation results of application to a fuel cell and battery application have been obtained whenever the input voltage exceeds the given 24V, at that time the load voltage will change from 180V to 230V. But due to this usage the load is disturbed and there is instability in the model. Using closed loop the output voltage is stabilized.

  2. Design and Implementation of Anti-windup PI Control on DC-DC Bidirectional Converter for Hybrid Vehicle Applications

    Directory of Open Access Journals (Sweden)

    Muh. Zakiyullah Romdlony

    2012-07-01

    Full Text Available Well-regulated DC bus voltage is the important point to guarantee the power demand in hybrid vehicle applications. Voltage regulation can be achieved with control method that build switching signal on DC-DC converter. This paper describes design and small scale experimental results of bus voltage regulation control of the DC-DC bidirectional converter with battery and supercapacitor as energy source. The control system consists of two control loops, the outer loop that get DC bus voltage feedback using PI anti-windup back calculation control method. This outer loop will generate a reference current for the inner loop that implement hysteresis control. The inner control loop will compare that reference curent with the source current obtained from the current sensor. Simulation and experimental results show that bus voltage is well-regulated under the load changes with 1% voltage ripple.

  3. FlexRay总线在电池储能系统中的应用%Application of FlexRay Bus in Battery Energy Storage System

    Institute of Scientific and Technical Information of China (English)

    马建业; 黄梅; 王占国; 刘彪; 盛大双

    2014-01-01

    当前大规模储能电池管理系统内部通信总线普遍采用CAN总线,使用FlexRay总线作为其内部总线替代传统的CAN总线,能较好地满足大规模电池储能系统( BESS)内部通信的要求。分析CAN总线用于大规模储能电池管理系统存在的不足以及FlexRay总线的优势。在BESS通信架构的基础上,介绍储能电池管理系统的通信架构,讨论FlexRay总线在大规模储能电池管理系统中的应用及主要方案。运用Network Designer与CANoe. FlexRay仿真验证FlexRay通信系统在大规模储能电池管理系统中应用的可行性,结果表明,与CAN总线相比,FlexRay总线用于储能电池管理系统中可以取得更好的效果。%CAN bus is normally used as internal bus in the large-scale Battery Energy Storage System ( BESS ) at present. FlexRay used as internal bus replacing CAN bus can well meet the requirements of internal communications in the large-scale battery energy storage system. The shortage of CAN bus which is used in the large-scale battery energy storage system and the superiority of FlexRay bus are analysed. Based on the simple introduction of the communication architecture of battery energy storage system, the communication architecture of energy storage battery management system is introduced by focus, and the feasibility of the application and major scheme of the FlexRay communication protocol in large-scale energy storage battery management system are discussed. Network Designer and CANoe. FlexRay are used to simulate the feasibility of FlexRay communication system used in the large-scale battery energy storage system. Simulation results prove that FlexRay bus used in energy storage battery management system can achieve good effects compared with CAN bus.

  4. Design and Control of a Multiple Input DC/DC Converter for Battery/Ultra-capacitor Based Electric Vehicle Power System

    DEFF Research Database (Denmark)

    Schaltz, Erik; Li, Zhihao; Onar, Omer;

    2009-01-01

    Battery/Ultra-capacitor based electrical vehicles (EV) combine two energy sources with different voltage levels and current characteristics. This paper focuses on design and control of a multiple input DC/DC converter, to regulate output voltage from different inputs. The proposed multi-input con......Battery/Ultra-capacitor based electrical vehicles (EV) combine two energy sources with different voltage levels and current characteristics. This paper focuses on design and control of a multiple input DC/DC converter, to regulate output voltage from different inputs. The proposed multi...

  5. Multilevel DC Link Inverter with Reduced Number of Switches and Batteries

    Directory of Open Access Journals (Sweden)

    Y. R. Manjunatha

    2014-05-01

    Full Text Available Multilevel inverters are the best solution for medium and high voltage power electronic drives. Because of its unique characteristic of synthesizing sinusoidal voltage with less harmonic contents using several DC sources. In a three phase multilevel inverter, each phase of a cascaded H-bridge inverter requires ‘n’ DC sources to obtain 2n + 1 output voltage levels. One particular  disadvantage  is that,  it  increases  number  of power semiconductor switches. To overcome this disadvantage a multilevel  DC  link  inverter  (MLDCLI with reduced number of switches and batteries is proposed.

  6. A Four-Phase High Voltage Conversion Ratio Bidirectional DC-DC Converter for Battery Applications

    Directory of Open Access Journals (Sweden)

    Li-Kun Xue

    2015-06-01

    Full Text Available This study presents a four-phase interleaved high voltage conversion ratio bidirectional DC-DC converter circuit based on coupled inductors and switched capacitors, which can eliminate the defects of conventional high voltage conversion ratio bidirectional DC-DC converters in terms of high-voltage/current stress, less efficiency and low-power limitation. Parallel channels are used to reduce current stress at the low-voltage side and series connected switched capacitors are used to enlarge voltage conversion ratio, reduce voltage stress and achieve auto current sharing. This paper proposes the operation principle, feature analysis and optimization design considerations. On this basis the objectives of high voltage conversion ratio, low voltage/current stress, high power density, high efficiency and high-power applications can be achieved. Some experimental results based on a 500 W prototype converter (24 V to 48 V at low-voltage side, 400 V at high-voltage side are given to verify the theoretical analysis and the effectiveness of the proposed converter.

  7. Design on CAN Network Project for Pure Electric Bus with Power Battery Replacement%换电式纯电动客车CAN网络方案设计

    Institute of Scientific and Technical Information of China (English)

    房永强

    2015-01-01

    结合某款换电式纯电动客车的研发与应用,介绍一种换电式纯电动客车三级CAN网络架构,以及合理的纯电动系统CAN总线管理方案。%Taking the R&D and application of a pure electric bus with the power battery replacement as an example, the author introduces a three-level CAN network architecture and appropriate management project of the control system based on the CAN bus of the pure electric system.

  8. A Feed-Forward Control Realizing Fast Response for Three-Branch Interleaved DC-DC Converter in DC Microgrid

    Directory of Open Access Journals (Sweden)

    Haojie Wang

    2016-07-01

    Full Text Available It is a common practice for storage batteries to be connected to DC microgrid buses through DC-DC converters for voltage support on islanded operation mode. A feed-forward control based dual-loop constant voltage PI control for three-branch interleaved DC-DC converters (TIDC is proposed for storage batteries in DC microgrids. The working principle of TIDC is analyzed, and the factors influencing the response rate based on the dual-loop constant voltage control for TIDC are discussed, and then the method of feed-forward control for TIDC is studied to improve the response rate for load changing. A prototype of the TIDC is developed and an experimental platform is built. The experiment results show that DC bus voltage sags or swells caused by load changing can be reduced and the time for voltage recovery can be decreased significantly with the proposed feed-forward control.

  9. Impact Safety Control Strategy for the Battery System of an Example Electric Bus

    Directory of Open Access Journals (Sweden)

    Zhen-po Wang

    2015-01-01

    Full Text Available This paper proposes a side impact safety control strategy for the battery system, aiming at defusing the hazards of unacceptable behaviors of the battery system such as high-voltage hazards. Based on some collision identification metrics, a side impact discrimination algorithm and a side impact severity algorithm are developed for electric buses. Based on the study on the time to break for power battery, the side impact discrimination algorithm response time is about 20 ms posing a great challenge to the side impact discrimination algorithm. At the same time, the reliability of the impact safety control strategy developed in this paper is evaluated for other plausible side impact signals generated by finite element analysis. The results verify that the impact safety control strategy exhibits robust performance and is able to trigger a breaking signal for power battery system promptly and accurately.

  10. DC Bus Control of Back-to-Back Connected Two-Level PWM Rectifier-Five-Level NPC Voltage Source Inverter to Torque Ripple Reduction in Induction Motor

    Directory of Open Access Journals (Sweden)

    Abdelkrim Thameur

    2015-01-01

    Full Text Available This paper proposes a regulation method of back-to-back connected two-level PWM rectifier-five-level Voltage Source Inverter (VSI in order to reduce the torque ripple in induction motor. First part is dedicated to the presentation of the feedback control of two-level PWM rectifier. In the second part, five-level Neutral Point Clamped (NPC voltage source inverter balancing DC bus algorithm is presented. A theoretical analysis with a complete simulation of the system is presented to prove the excellent performance of the proposed technique.

  11. Interfacing the septa movement (DC motors) equipment to the PS control system and the MIL1553 bus

    CERN Document Server

    Dehavay, Claude

    1995-01-01

    Continuing the rejuvenation of the PS Control system , this application replaces the Single Transceiver Hybrid used to interface the Septa Movement Fquipment by a G64 system connected to the VME crate via the MIL1553 bus. This note explains the G64 hardware interface and details the standard message as defined in the Control Protocole for Power Converter, RF and Stepping Motor equipment.

  12. Connected Ways and Spontaneous Combustion Fire of Battery Piles for Pure Electric City Bus%纯电动城市客车电池组的连接方式与自燃火灾

    Institute of Scientific and Technical Information of China (English)

    车兆华

    2012-01-01

    The author introduces some connected ways of battery piles for pure electric city bus, and analyzes the reasons of causing the batteries spontaneous combustion fire.%介绍纯电动客车动力电池组的几种连接方式,分析造成电池自燃火灾的原因。

  13. Interfacing the septa movement (DC motor) equipment to the PS control system and the MIL1553 bus

    CERN Document Server

    Dehavay, Claude

    1993-01-01

    Continuing the rejuvenation of the PS Control system , it is planned to replace the Single Transceiver Hybrid used to interface the Septa Movement Equipment by a G64 system connected to the VME crate via the MIL1553 bus. This note explains the G64 hardware interface and details the standard message as defined in the Control Protocole for Power Converter, RF and Stepping Motor equipment.

  14. Fast Charge Battery Electric Transit Bus In-Use Fleet Evaluation: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Prohaska, Robert; Eudy, Leslie; Kelly, Kenneth

    2016-05-06

    The focus of this interim fleet evaluation is to characterize and evaluate the operating behavior of Foothill Transit's fast charge battery electric buses (BEBs). Future research will compare the BEBs' performance to conventional vehicles. In an effort to better understand the impacts of drive cycle characteristics on advanced vehicle technologies, researchers at the National Renewable Energy Laboratory analyzed over 148,000 km of in-use operational data, including driving and charging events. This analysis provides an unbiased evaluation of advanced vehicle technologies in real-world operation demonstrating the importance of understanding the effects of road grade and heating, ventilating and air conditioning requirements when deploying electric vehicles. The results of this analysis show that the Proterra BE35 demonstrated an operating energy efficiency of 1.34 kWh/km over the data reporting period.

  15. Battery Management System—Balancing Modularization Based on a Single Switched Capacitor and Bi-Directional DC/DC Converter with the Auxiliary Battery

    OpenAIRE

    Mohamed Daowd; Mailier Antoine; Noshin Omar; Philippe Lataire; Peter Van Den Bossche; Joeri Van Mierlo

    2014-01-01

    Lithium-based batteries are considered as the most advanced batteries technology, which can be designed for high energy or high power storage systems. However, the battery cells are never fully identical due to the fabrication process, surrounding environment factors and differences between the cells tend to grow if no measures are taken. In order to have a high performance battery system, the battery cells should be continuously balanced for maintain the variation between the cells as small ...

  16. A Novel Integrated Magnetic Structure Based DC/DC Converter for Hybrid Battery/Ultracapacitor Energy Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Onar, Omer C [ORNL

    2012-01-01

    This manuscript focuses on a novel actively controlled hybrid magnetic battery/ultracapacitor based energy storage system (ESS) for vehicular propulsion systems. A stand-alone battery system might not be sufficient to satisfy peak power demand and transient load variations in hybrid and plug-in hybrid electric vehicles (HEV, PHEV). Active battery/ultracapacitor hybrid ESS provides a better solution in terms of efficient power management and control flexibility. Moreover, the voltage of the battery pack can be selected to be different than that of the ultracapacitor, which will result in flexibility of design as well as cost and size reduction of the battery pack. In addition, the ultracapacitor bank can supply or recapture a large burst of power and it can be used with high C-rates. Hence, the battery is not subjected to supply peak and sharp power variations, and the stress on the battery will be reduced and the battery lifetime would be increased. Utilizing ultracapacitor results in effective capturing of the braking energy, especially in sudden braking conditions.

  17. Savannah River bus project

    Energy Technology Data Exchange (ETDEWEB)

    Summers, W.A. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1998-08-01

    The H2Fuel Bus is the world`s first hybrid hydrogen electric transit bus. It was developed through a public/private partnership involving several leading technology and industrial organizations in the Southeast, with primary funding and program management provided by the Department of Energy. The primary goals of the project are to gain valuable information on the technical readiness and economic viability of hydrogen buses and to enhance the public awareness and acceptance of emerging hydrogen technologies. The bus has been operated by the transit agency in Augusta, Georgia since April, 1997. It employs a hybrid IC engine/battery/electric drive system, with onboard hydrogen fuel storage based on the use of metal hydrides. Initial operating results have demonstrated an overall energy efficiency (miles per Btu) of twice that of a similar diesel-fueled bus and an operating range twice that of an all-battery powered electric bus. Tailpipe emissions are negligible, with NOx less than 0.2 ppm. Permitting, liability and insurance issues were addressed on the basis of extensive risk assessment and safety analyses, with the inherent safety characteristic of metal hydride storage playing a major role in minimizing these concerns. Future plans for the bus include continued transit operation and use as a national testbed, with potential modifications to demonstrate other hydrogen technologies, including fuel cells.

  18. Electrochemical treatment of tannery effluent using a battery integrated DC-DC converter and solar PV power supply--an approach towards environment and energy management.

    Science.gov (United States)

    Iyappan, K; Basha, C Ahmed; Saravanathamizhan, R; Vedaraman, N; Tahiyah Nou Shene, C A; Begum, S Nathira

    2014-01-01

    Electrochemical oxidation of tannery effluent was carried out in batch, batch recirculation and continuous reactor configurations under different conditions using a battery-integrated DC-DC converter and solar PV power supply. The effect of current density, electrolysis time and fluid flow rate on chemical oxygen demand (COD) removal and energy consumption has been evaluated. The results of batch reactor show that a COD reduction of 80.85% to 96.67% could be obtained. The results showed that after 7 h of operation at a current density of 2.5 A dm(-2) and flow rate of 100 L h(-1) in batch recirculation reactor, the removal of COD is 82.14% and the specific energy consumption was found to be 5.871 kWh (kg COD)(-1) for tannery effluent. In addition, the performance of single pass flow reactors (single and multiple reactors) system of various configurations are analyzed.

  19. Energy Management of a Hybrid AC–DC Micro-Grid Based on a Battery Testing System

    Directory of Open Access Journals (Sweden)

    Bo Long

    2015-02-01

    Full Text Available Energy Recovery Battery Testing Systems (ERBTS plays an important role in battery manufacture. The conventional ERBTS configuration contains a fundamental transformer, and a bidirectional Direct Current (DC–DC and Alternating Current (AC–DC converter. All ERBTS are connected in parallel, thus constituting a special and complicated AC micro-grid system. Aiming at addressing their low energy recovery efficiency, complex grid-connected control algorithm issues for islanded detection, and complicated power circuit topology issues, a hierarchical DC-link voltage hybrid AC–DC micro-grid that contains composite energy storing devices is proposed. Moreover, an energy management optimal scheme for the proposed scheme is put forward. The system configuration of the proposed scheme is described in detail. Compared to the conventional scheme, the proposed scheme has the merits of simplified power circuit topology, no need for phase synchronous control, and much higher energy recovery efficiency and reliability. The validity and effectiveness of the proposed technique is verified through numerous experimental results.

  20. Studi Komparasi Fungsi Keanggotaan Fuzzy sebagai Kontroler Bidirectional DC-DC Converter pada Sistem Penyimpan Energi

    Directory of Open Access Journals (Sweden)

    Eka Prasetyono

    2015-09-01

    Full Text Available Bidirectional DC-DC converter is needed in the energy storage system. The converter topology used in this paper was a non-isolated bidirectional DC-DC buck-boost converter. This converter worked in two ways, which the charging mode stored energy into battery when load current was less than nominal main DC current (set point and discharging mode transferred energy from battery to the load when its current exceeded set point value. Both of these modes worked automatically according to the load current. The charging and discharging currents were controlled by fuzzy logic controller which was implemented on microcontroller ARM Cortex-M4F STM32F407VG. This paper compares two types of fuzzy membership function (triangular and sigmoid in controlling bidirectional DC-DC converter. The results showed that fuzzy logic controller with triangle membership function and sigmoid as control bidirectional DC-DC converter had no significant different response, both had an average error for charging and discharging process under 4% with ripple current on the main DC bus around 0.5%. The computing time of program for fuzzy logic controller with triangular membership functions had 19.01% faster than sigmoid, and fuzzy logic computation time on a microcontroller with hardware floating point was 60% faster than software floating point.

  1. Comparison of control schemes for a fuel cell hybrid tramway integrating two dc/dc converters

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, L.M.; Garcia, P.; Garcia, C.A. [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n, 11202 Algeciras (Cadiz) (Spain); Torreglosa, J.P.; Jurado, F. [Department of Electrical Engineering, EPS Linares, University of Jaen, C/Alfonso X, n 28. 23700 Linares (Jaen) (Spain)

    2010-06-15

    This paper describes a comparative study of two control schemes for the energy management system of a hybrid tramway powered by a Polymer Electrolyte Membrane (PEM) Fuel Cell (FC) and an Ni-MH battery. The hybrid system was designed for a real surface tramway of 400 kW. It is composed of a PEM FC system with a unidirectional dc/dc boost converter (FC converter) and a rechargeable Ni-MH battery with a bidirectional dc/dc converter (battery converter), both of which are coupled to a traction dc bus. The PEM FC and Ni-MH battery models were designed from commercially available components. The function of the two control architectures was to effectively distribute the power of the electrical sources. One of these control architectures was a state machine control strategy, based on eight states. The other was a cascade control strategy which was used to validate the results obtained. The simulation results for the real driving cycle of the tramway reflected the optimal performance of the control systems compared in this study. (author)

  2. BUS 650 UOP Material - bus650dotcom

    OpenAIRE

    lucky108

    2015-01-01

    For more course tutorials visit www.bus650.com BUS 650 Week 1 DQ 1 The Role of Financial Management in a Firm BUS 650 Week 1 DQ 2 Short Term or Long Term View BUS 650 Week 1 Financial Management Challenges BUS 650 Week 2 DQ 1 Initial Investment BUS 650 Week 2 DQ 2 Managing Earnings BUS 650 Week 2 Return on Investment Education Funding BUS 650 Week 3 DQ 1 GAAP vs. IFRS BUS 650 Week 3 DQ 2 Capital Rationing BUS 650 Week 3 Journal Capital Budgeting BUS 650 Week 3 Management of Working Capital Ca...

  3. DC Bus Voltage Constant Control Technology in Wind Power System with Dual PWM Converter%风电系统双PWM变换器直流母线电压控制技术

    Institute of Scientific and Technical Information of China (English)

    刘波; 贺志佳; 金昊

    2015-01-01

    双PWM变换器是目前风力发电系统广泛使用的控制电路,其直流母线是实现风电系统能量传输与转换的中间环节,母线电压的稳定与否直接关系到能否实现对机侧和网侧变换器独立控制及整个系统的安全稳定运行,减小直流母线电压波动成为双PWM变换器控制技术的研究热点,并得到了广泛的关注。对风电系统双PWM变换器直流母线电压控制技术进行综述,分析了基于电容电流直接控制、直接功率控制、协调控制及模糊控制等各种控制策略的优缺点,指出了存在的问题、今后的研究重点及发展趋势。%Dual PWM converter control system is widely used in wind power system,the DC bus is the interme-diate link of energy transfer and conversion in wind power system,bus voltage stability is directly related to the realization of the generator side and grid side converter control and the stable operation of the whole system. How to reduce the fluctuation of DC bus voltage has become the research focus of dual PWM converter control technology,and received wide attention. DC bus voltage control technology in wind power system with dual PWM converter was summarized. Analyzed the advantages and disadvantages of the direct control based on ca-pacitive current,direct power control,coordination control,fuzzy control and other control strategies. Pointed out the problem in each of control strategies and the research emphases and development trend in the future.

  4. Research on control strategy for battery system of photovoltaic power system based on bi-directional DC/DC converter%基于双向变换器的光伏储能控制策略研究

    Institute of Scientific and Technical Information of China (English)

    李鑫; 解璞

    2016-01-01

    独立光伏系统中,储能环节起到平衡功率、稳定系统的关键作用,而合理的控制策略能将储能系统与光伏阵列有机地结合起来,双向 DC/DC变换器正是完成此目标的桥梁。本文在对已有的双向 DC/DC变换器进行优化设计的基础上,提出了一种兼顾电池电性能与系统稳定性的储能系统控制策略。在 Matlab仿真环境下搭建了带有双向 DC/DC变换器的独立光伏系统模型,并对储能系统的工作情况进行仿真,验证了变换器拓扑结构与储能控制策略的合理性。%The independent photovoltaic system needs energy storage in order to balance the power and improve its stability of power generation. A scientiifc control strategy can combine the PV cells with the battery system organically. The bi-directional DC/DC converter can be the bridge to achieve this target. This paper presents a control strategy which takes account of battery electrical performance and system stability based on optimization on the circuit topology of bi-directional DC/DC already underway. Moreover, the charge and discharge circuit based on bi-directional DC/DC converter and an integral independent PV power system are built with Matlab. The simulation results show the correctness of the charge and discharge circuit topology and control strategy.

  5. BUS 372 ASH Material - bus372dotcom

    OpenAIRE

    lucky108

    2015-01-01

    For more course tutorials visit www.bus372.com       BUS 372 Week 1 DQ 1 The Role of Unionization (Ash Course) BUS 372 Week 1 DQ 2 Meeting Member Needs (Ash Course) BUS 372 Week 2 DQ 1 Profit Interest and Employee Interest (Ash Course) BUS 372 Week 2 DQ 2 Union Requirements (Ash Course) BUS 372 Week 2 Assignment Changing Landscape of Unions (Ash Course) BUS 372 Week 2 Quiz (Ash Course) BUS 372 Week 3 DQ 1 Strikes (Ash Course) BUS ...

  6. BUS 372 Tutorials / bus372dotcom

    OpenAIRE

    sunshine3811

    2015-01-01

    For more course tutorials visit www.bus372.com       BUS 372 Week 1 DQ 1 The Role of Unionization (Ash Course) BUS 372 Week 1 DQ 2 Meeting Member Needs (Ash Course) BUS 372 Week 2 DQ 1 Profit Interest and Employee Interest (Ash Course) BUS 372 Week 2 DQ 2 Union Requirements (Ash Course) BUS 372 Week 2 Assignment Changing Landscape of Unions (Ash Course) BUS 372 Week 2 Quiz (Ash Course) BUS 372 Week 3 DQ 1 Strikes (Ash Course) BUS ...

  7. BUS 401 Courses / bus401tutorialdotcom

    OpenAIRE

    uophelp

    2015-01-01

     FOR MORE CLASSES VISIT www.bus401tutorial.com BUS 401 Week 1 DQ 1 Corporate Income Tax and Real Interest Rates (Ash Course) BUS 401 Week 1 DQ 2 Cash Flow and Ratio Analysis (Ash Course)  BUS 401 Week 1 Assignment Ratio Analysis (Ash Course) BUS 401 Week 1 Quiz (Ash Course) BUS 401 Week 2 DQ 1 Annuity and Capital Asset Pricing (Ash Course) BUS 401 Week 2 DQ 2 Bonds and Common Stock (Ash Course) BUS 401 Week 2 Assignment Alternative Investments (Ash Co...

  8. BUS 401 COURSES / bus401tutordotcom

    OpenAIRE

    uophelp

    2015-01-01

    FOR MORE CLASSES VISIT www.bus401tutor.com   BUS 401 Week 1 DQ 1 Corporate Income Tax and Real Interest Rates (Ash Course) BUS 401 Week 1 DQ 2 Cash Flow and Ratio Analysis (Ash Course)  BUS 401 Week 1 Assignment Ratio Analysis (Ash Course) BUS 401 Week 1 Quiz (Ash Course) BUS 401 Week 2 DQ 1 Annuity and Capital Asset Pricing (Ash Course) BUS 401 Week 2 DQ 2 Bonds and Common Stock (Ash Course) BUS 401 Week 2 Assignment Alternative Investments (Ash ...

  9. 基于蓄电池负载DC/DC变换器的数字式前馈控制器仿真分析%Simulation Analysis on Digital Feed-Forward Contoller for DC/DC Converter with Battery Load

    Institute of Scientific and Technical Information of China (English)

    张小勇; 谢伟; 李梅

    2012-01-01

    采用前馈控制的方式,可以提高带蓄电池负载的DC/DC变换器的动态性能.针对列车上采用的半桥式DC/DC电源装置设计了与其相适应的前馈控制器,并且对该系统进行了仿真.仿真分析表明,这种前馈控制方式能够大大改善系统的动态性能以及稳定精度.%Dynamic performance of DC/DC converter with battery load could be enhanced by adopting feed-forward control method. Feed-forward controller for vehicle supply based on half-bridge topological DC/DC converter was designed and simulated, which was proved to greatly enhance the dynamic and stability performance of the system.

  10. Optimal Strategy for Economic Operation of Electric Bus Battery Swapping Station%快换式电动公交充电站经济运行优化策略

    Institute of Scientific and Technical Information of China (English)

    杨少兵; 吴命利; 姜久春; 赵伟

    2014-01-01

    备用电池数量、充电时长是影响换电站换电能力的主要因素。基于车辆进站流量分析,提出了描述换电需求和电池充电产量的函数,进一步分析了两者之间的关系,提出了针对电价峰段的充电控制方法。以北京奥运电动公交充电站为例阐述了经济运行优化策略的应用步骤,并编写了计算机仿真程序进行验证。结果表明:所提经济运行优化策略在满足任意时刻换电需求的条件下可显著降低电价峰段用电量,较大幅度地减少换电站的电费支出。同时,该策略所包含的算法及边界条件非常清晰,容易嵌入充电管理系统实现换电站的经济运行优化控制。%The reserved battery number and the charging duration are main factors to affect the energy supply capacity of electric bus battery swapping station. Based on the analysis of vehicle flow, two formulas are presented to describe required battery amount and charged battery amount respectively. Moreover, with analyzing the relation between the two formulas, a charging control method for the peak period is provided. According to the field test data and statistical results of the electric bus swapping station for 2008 Beijing Olympic Games, the procedures of optimal strategy for economic operation have been given. Then a computer simulation program is prepared to verify the strategy. Simulation results show that the proposed strategy can reduce power consumption of peak periods and electricity costs markedly while it meets the condition at swapping demand. In addition, the algorithm and boundary conditions are very clear, and it is easy to be embedded into a charging management system to implement economic optimization for bus battery swapping stations.

  11. A High-Gain Three-Port Power Converter with Fuel Cell, Battery Sources and Stacked Output for Hybrid Electric Vehicles and DC-Microgrids

    OpenAIRE

    Ching-Ming Lai; Ming-Ji Yang

    2016-01-01

    This paper proposes a novel high-gain three-port power converter with fuel cell (FC), battery sources and stacked output for a hybrid electric vehicle (HEV) connected to a dc-microgrid. In the proposed power converter, the load power can be flexibly distributed between the input sources. Moreover, the charging or discharging of the battery storage device can be controlled effectively using the FC source. The proposed converter has several outputs in series to achieve a high-voltage output, wh...

  12. BUS 660 ASH Course Tutorial / bus660dotcom

    OpenAIRE

    vasanthi moola

    2015-01-01

    BUS 660 Entire Course For more course tutorials visit www.bus660.com   BUS 660 Week 1 Assignment Developing Leaders at UPS BUS 660 Week 2 Assignment Leadership Style BUS 660 Week 3 Assignment Leadership Traits BUS 660 Week 4 Assignment Leadership Skills BUS 660 Week 5 Assignment Big Changes for a Small Hospital BUS 660 Week 6 Assignment Research Paper BUS 660 Week 1 DQ 1 Leadership Defined BUS 660 Week 1 DQ 2 Education and Experience BUS 66...

  13. Decision making model for lifecycle assessment of lithium-ion battery for electric vehicle - A case study for smart electric bus project in Korea

    Science.gov (United States)

    Thein, Sabai; Chang, Yoon Seok

    2014-03-01

    Lithium-ion (Li-ion) battery is part of our everyday life. There are many automobiles invented today that operates by Li-ion batteries. The issue with batteries is that they lose capacity and reliability over time as they are charged and discharged. This paper introduces a lifecycle assessment system for Li-ion EV battery considering the condition of each battery which helps decision making. The proposed research concerns not only for the ad-hoc condition but also regular condition of the Li-ion EV battery. We apply the Markov Decision Process (MDP) with selected policies for the measurement of each stage probability. The result shows that we could monitor product aging status with the proposed algorithm. It also shows that the calculated product life span was longer than the general warranty time period.

  14. A High-Gain Three-Port Power Converter with Fuel Cell, Battery Sources and Stacked Output for Hybrid Electric Vehicles and DC-Microgrids

    Directory of Open Access Journals (Sweden)

    Ching-Ming Lai

    2016-03-01

    Full Text Available This paper proposes a novel high-gain three-port power converter with fuel cell (FC, battery sources and stacked output for a hybrid electric vehicle (HEV connected to a dc-microgrid. In the proposed power converter, the load power can be flexibly distributed between the input sources. Moreover, the charging or discharging of the battery storage device can be controlled effectively using the FC source. The proposed converter has several outputs in series to achieve a high-voltage output, which makes it suitable for interfacing with the HEV and dc-microgrid. On the basis of the charging and discharging states of the battery storage device, two power operation modes are defined. The proposed power converter comprises only one boost inductor integrated with a flyback transformer; the boost and flyback circuit output terminals are stacked to increase the output voltage gain and reduce the voltage stress on the power devices. This paper presents the circuit configuration, operating principle, and steady-state analysis of the proposed converter, and experiments conducted on a laboratory prototype are presented to verify its effectiveness.

  15. Control of a Multi-Functional Inverter for Grid Integration of PV and Battery Energy Storage System

    DEFF Research Database (Denmark)

    Mousazadeh, Seyyed Yousef; Firoozabadi, Mehdi Savaghebi; Beirami, A.;

    2015-01-01

    This paper presents a multi-functional control of a DC/AC inverter for Power Quality compensation of nonlinear and unequal local loads and grid integration of hybrid photovoltaic (PV) and battery energy storage systems. Multi-layer neural network estimator and a DC/DC converter are used for maximum...... power point tracking (MPPT) of PV array. The power system is 3-phase 4-wires and the DC/AC inverter is chosen 4-leg three phase inverter which has good performance in presence of zero sequence components. Battery energy storage is connected to PV system in common DC bus and a power management strategy...... and nonlinear local loads. The simulation results which implemented in MATLAB/SIMULINK software verify the effectiveness of the system....

  16. Energy efficiency of different bus subsystems in Belgrade public transport

    Directory of Open Access Journals (Sweden)

    Mišanović Slobodan M.

    2015-01-01

    Full Text Available Research in this paper comprised experimental determination of energy efficiency of different bus subsystems (diesel bus, trolleybus and fully electric bus on chosen public transport route in Belgrade. Experimental measuring of energy efficiency of each bus type has been done based on the analysis of parameters of vehicle driving cycles between stops. Results of this analysis were basis for development of theoretical simulation model of energy efficiency. The model was latter compared with the results of simulation done by "Solaris bus & Coach" company for the chosen electric bus route. Based on demonstrated simulation, characteristics of electric bus batteries were defined, the method and dynamic of their recharge was suggested, as well as choice for other aggregates for drive system and technical characteristics for the electric buses were suggested.

  17. Design of DC/AC convert protection circuit of single-phase battery discharging device%单相蓄电池放电装置中DC/AC变换保护电路的设计

    Institute of Scientific and Technical Information of China (English)

    易映萍; 郭利辉; 刘普; 邓祥纯

    2009-01-01

    介绍了一种新型的单相有源逆变蓄电池回馈放电装置中DC/AC变换保护电路的设计方法,电路具有IGBT过流、过热、直流过压、输出交流过压、输出交流欠压、输出交流过流等多种保护类型,对从事电力电子技术特别是蓄电池放电技术研究的工程技术人员具有较高的参考价值.%This paper brings forward a new style of discharging device--single-phase active inverter battery feedback discharging device, the design method of DC/AC convert protection circuit is obtained. The circuit has multifold protection functions such as IGBT over-current and over thermal protection, DC over-voltage, AC over-voltage or low-voltage, output over-current, etc. This method will have high value for the engineers.

  18. DESIGN AND EXPERIMENT OF ELECTRIC BUS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Performance and reliability experiments on BJD-6100EV electric buses, jointly developed by Beijing Institute of Technology and Beijing Public Transport Company, are introduced. Output power model of battery pack is established and maximum output power is analyzed. A permanent magnetic direct current (PMDC) motor with enhanced windings is developed for the bus. Torque-speed characteristics of the motor are modeled and performance of electric bus is analyzed. Computational method of the range of electric bus is proposed and discussed. Experiments show that electric bus can realize design requirements. Computational methods are verified with the help of field test. It is expected that design and computation method will provide helpful reference to development of electric vehicles.

  19. Research and development of a phosphoric acid fuel cell/battery power source integrated in a test-bed bus. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-30

    This project, the research and development of a phosphoric acid fuel cell/battery power source integrated into test-bed buses, began as a multi-phase U.S. Department of Energy (DOE) project in 1989. Phase I had a goal of developing two competing half-scale (25 kW) brassboard phosphoric acid fuel cell systems. An air-cooled and a liquid-cooled fuel cell system were developed and tested to verify the concept of using a fuel cell and a battery in a hybrid configuration wherein the fuel cell supplies the average power required for operating the vehicle and a battery supplies the `surge` or excess power required for acceleration and hill-climbing. Work done in Phase I determined that the liquid-cooled system offered higher efficiency.

  20. Switching coordination of distributed dc-dc converters for highly efficient photovoltaic power plants

    Science.gov (United States)

    Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja

    2014-09-09

    A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.

  1. 基于电压下垂法的直流微电网混合储能系统控制策略%Control Strategy of Hybrid Energy Storage Systems in DC Microgrid Based on Voltage Droop Method

    Institute of Scientific and Technical Information of China (English)

    文波; 秦文萍; 韩肖清; 王鹏; 刘家赢

    2015-01-01

    Aiming at stabilizing the DC bus voltage and optimizing the working process of the batteries, this paper presents a control strategy of hybrid energy storage systems in DC microgrid based on voltage droop method. The control strategy makes use of the ultracapacitor compensating the high-frequency components of bus power according to the DC bus voltage, indirectly compensates low-frequency components of bus power through the energy supplement of the batteries on the ultracapacitor, and takes advantage of the unable mutation characteristics of ultracapacitor voltage to achieve the smooth control of battery current. The control system can automatically switch work mode according to the conditions of DC bus voltage, ultracapacitor voltage and the state of charge (SOC) of battery. The experiments show that the control strategy can automatically adjust the output of batteries and ultracapacitor, maintain light fluctuation of DC bus voltage around rating, effectively reduce the frequency of battery charging and discharging and extend its using life.%以稳定直流母线电压和优化蓄电池工作过程为目的,提出了一种基于电压下垂法的直流微电网混合储能控制策略。该控制策略根据直流母线电压信息,利用超级电容快速补偿母线功率缺额的高频部分;通过蓄电池对超级电容进行能量补充,间接补偿母线功率缺额的低频部分;利用超级电容电压不能突变的特点,实现对蓄电池电流的平滑控制。控制系统以直流母线电压、超级电容电压及蓄电池荷电状态为判断条件,自动切换工作模式。实验表明,该控制策略可自动调节蓄电池和超级电容出力,维持直流母线电压在额定值附近小范围波动,有效地减小了蓄电池充放电次数,延长其使用寿命。

  2. High Performance BDR for the PCU of AlphaBus

    Science.gov (United States)

    Subrier, Laurent; Besdel, Patrick; Daubresse, Thierry; Trehet, Eric

    2008-09-01

    Very high-power satellites for Telecom missions require 100V bus. Some Telecom payloads may be used in TDMA mode with a power modulation up to 30% of the Payload power. Full performance of the PCU is required in this case even in eclipse mode. It is clear that this requirement is very demanding especially for the BDR design.100V bus system leads making this requirement more difficult as Bus and Battery short-circuit protections have to operate under a voltage of 100V. This paper describes first the overall BDR design with a special focus on the innovative battery short-circuit protection that is not achieved by a "classical" series SSPC on the battery line.The constraints brought by the TDMA mode are detailed, especially on the input filter of the BDR in presence of large battery inductance. The solution developed to cope with large TDMA current is then presented with the associated TDMA performance.

  3. BUS 210 Course tutorial/ indigohelp

    OpenAIRE

    WVFD

    2015-01-01

    For more classes visit www.indigohelp.com   BUS 210 Week 1 DQ1 and DQ2 BUS 210 Week 1 Checkpoint Business Models and Systems (2 Sets) BUS 210 Week 1 Knowledge Check BUS 210 Week 2 CheckPoint Business Organization  (2 Sets) BUS 210 Week 2 Knowledge Check BUS 210 Week 2 Assignment Evolution of Business Presentation (2 Sets) BUS 210 Week 3 DQ 1 and DQ 2 BUS 210 Week 3 CheckPoint Code of Ethics (2 Sets) BUS 210 Week 3 Knowledge Check BUS 2...

  4. A Feed-Forward Control Realizing Fast Response for Three-Branch Interleaved DC-DC Converter in DC Microgrid

    DEFF Research Database (Denmark)

    Wang, Haojie; Han, Minxiao; Yan, Wenli;

    2016-01-01

    It is a common practice for storage batteries to be connected to DC microgrid buses through DC-DC converters for voltage support on islanded operation mode. A feed-forward control based dual-loop constant voltage PI control for three-branch interleaved DC-DC converters (TIDC) is proposed...

  5. Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

    Science.gov (United States)

    Benaouadj, M.; Aboubou, A.; Ayad, M. Y.; Bahri, M.; Boucetta, A.

    2016-07-01

    In this work, an optimal control (under constraints) based on the Pontryagin's maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: - Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, - Keep fuel cells working at optimal power delivery conditions, - Maintain constant voltage across the common DC bus, - Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control.Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  6. PCI bus demystified

    CERN Document Server

    Abbott, Doug

    2004-01-01

    The peripheral component interconnect (PCI) bus is the dominant bus system used to connect the different elements making up today''s high-performance computer systems. Different PCI implementations have also been developed for such applications as telecommunications and embedded computing. If an application calls for high speed, high reliability, flexible configuration, and bus mastering, then PCI is the only logical bus choice. This book is an applications-oriented introduction to the PCI bus, with an emphasis on implementing PCI in a variety of computer architectures. Special attention is given to industrial and mission-critical applications of PCI bus.·Fully describes PCI electrical specifications, mechanical requirements, and signal types·Covers advanced topics through numerous design examples to increase the readers understanding of the subject ·Includes updated coverage of PCI-X 2.0

  7. Control of the DC-DC Converter used into Energy Generation System

    International Nuclear Information System (INIS)

    This paper presents an investigation of the DC-DC Converter controller used into Energy Generation System. The full bridge is used into an Energy Generation System (EGS) as second power interface between the energy source and the high DC bus. The simulation results show that the DC-DC Converter behavior can be improved using a well designed PI control surface. The used Simulink models for the EGS blocks and some design considerations are presented, too. (authors)

  8. Intelligent Bus Stops in the Flexible Bus Systems

    Directory of Open Access Journals (Sweden)

    Razi Iqbal

    2014-09-01

    Full Text Available The purpose of this paper is to discuss Intelligent Bus Stops in a special Demand Responsive Transit (DRT, the Flexible Bus System. These Intelligent Bus Stops are more efficient and information rich than Traditional Bus Stops. The real time synchronization of the Flexible Bus System makes it unique as compared to Traditional Bus Systems. The Main concern is to make Bus Stops intelligent and information rich. Buses are informed about the no. of passengers waiting at the upcoming Bus Stops. If there are no passengers to ride or get off on upcoming Bus Stop, the Bus can skip that Bus Stop and head towards the next Bus Stop where passenger is waiting, which will decrease the ride time of the passengers on the Bus and also the wait time of the passengers waiting on the upcoming Bus Stops. Providing more information at Bus Stops about the Destination (Time to Destination, Distance to Destination etc. and Buses (Bus Location, Arrival Time of Bus etc. makes it easier for the passengers to decide whether to ride a particular Bus or not.

  9. Examining the Optimal Fuel Type for Urban Bus Operations

    OpenAIRE

    CAULFIELD, BRIAN

    2010-01-01

    PUBLISHED Washington D.C. Public service fleets offer an attractive option for introducing renewable fuels and alternative technologies on a large scale, which allow for the reduction of both greenhouse gas emissions and exhaust air pollutants. This paper ex amines the use of biomethane (bio-CNG) and compressed natural gas (CNG) for part of the bus fleet in Dublin. Dublin is typical of many international urban centres with a large bus fleet; therefore the results...

  10. TPG bus passes

    CERN Multimedia

    Staff Association

    2013-01-01

    The CERN Staff Association will stop selling TPG bus passes. All active and retired members of the CERN personnel will be able to purchase Unireso bus passes from the CERN Hostel - Building 39 (Meyrin site) from 1st February 2013. For more information: https://cds.cern.ch/journal/CERNBulletin/2013/04/Announcements/1505279?ln=en

  11. 抑制直流母线电压波动的四象限级联型变频器前馈控制策略%A Feed-Forward Scheme for A Four-Quadrant Cascade Converter to Restrain DC Bus Voltage Ripple

    Institute of Scientific and Technical Information of China (English)

    邱长青; 黄声华

    2015-01-01

    四象限级联型变频器功率单元 H 桥的瞬时输出功率以2倍和4倍频率脉动,使得直流母线产生2次和4次纹波电压。单个功率单元输入端PWM整流器采用前馈控制策略能有效抑制母线电压波动,且总的并网电流无低次谐波。从功率单元的数学模型出发,推导出输入输出的瞬时有功功率,提出了基于瞬时 abc 理论的瞬时有功电流前馈控制来抑制直流母线电压波动,同时建立了基于Kalman滤波的负载电流估计模型。最后通过功率单元实验测试,验证了控制策略的可行性。%The instantaneous output power of the power cell H-bridge in four-quadrant cascade converter pulsates at twice and quadruple the output frequency, generating the second and fourth harmonic DC bus voltage. Using feed-forward control scheme in PWM rectifier of single power cell can effectively restrain DC bus voltage ripple and make the total grid-connected current without low-order harmonics. From the mathematical model of power cell, the instantaneous active power is derived. Based on instantaneous abc theory, instantaneous active current feed-forward control have been proposed to restrain the DC bus voltage ripple. Moreover, load current estimation model based on Kalman theory is established. Finally, the experimental results are given to prove the effectiveness of the proposed control scheme.

  12. 基于混杂Petri网的共直流母线交流传动系统建模与节能控制%Modeling and energy saving control for common DC bus AC drive system based on hybrid Petri nets

    Institute of Scientific and Technical Information of China (English)

    李继方; 汤天浩; 姚刚

    2011-01-01

    通过引入混杂系统理论,在分析系统运行过程的基础上,建立了共直流母线交流传动系统混杂Petri网模型和电机功率模型.在此基础上提出了一种基于配对理论的节能控制算法,即在电机状态可调控时段,通过改变随机运行状态,使耗能状态激发与回馈状态激发模糊配对的电机状态调控算法.采用该方法的直流母线功率仿真结果表明,该方法能有效地调整控制电机状态,使处在耗能状态电机最大限度地吸收制动状态电机再生的电能,减小了直流母线功率波动,提高了系统性能.%This paper introduces the hybrid system theory and establishes a common DC bus AC drive system hybrid Petri nets model and a motor power model based on the analysis of the system operation process. On this basis an energy saving control algorithm based on matching theory is proposed, namely the motor state adjusting algorithm which gets fuzzy pair of energy consumption state excitation and feedback state excitation through changing the random operation state in the controllable period of motor state. The results of simulation on DC bus power adopting this method show that it can effectively adjust and control the motor state, make the motor in energy consumption state absorb the electrical energy regenerated by motor in braking mode to a large extent,thus can reduce the DC bus power fluctuation and improve the system performance.This work is supported by National Natural Science Foundation of China (No. 51007056).

  13. Microprocessor control of multiple peak power tracking DC/DC converters for use with solar cell arrays

    Science.gov (United States)

    Frederick, Martin E. (Inventor); Jermakian, Joel (Inventor)

    1991-01-01

    A method and an apparatus is provided for efficiently controlling the power output of a solar cell array string or a plurality of solar cell array strings to achieve a maximum amount of output power from the strings under varying conditions of use. Maximum power output from a solar array string is achieved through control of a pulse width modulated DC/DC buck converter which transfers power from a solar array to a load or battery bus. The input voltage from the solar array to the converter is controlled by a pulse width modulation duty cycle, which in turn is controlled by a differential signal controller. By periodically adjusting the control voltage up or down by a small amount and comparing the power on the load or bus with that generated at different voltage values a maximum power output voltage may be obtained. The system is totally modular and additional solar array strings may be added to the system simply by adding converter boards to the system and changing some constants in the controller's control routines.

  14. Design, optimization and new solutions for DC/DC converters in hybrid vehicles; Design, Optimierung und neue Loesungen fuer DC/DC-Wandler in Hybridfahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Pledl, Georg; Lutter, Peter [Finepower GmbH, Ismaning (Germany)

    2010-07-01

    Especially in automotive engineering, the big aim of electronic device development is to combine minimum possible weight, highest efficiency and low electromagnetic interference. Since there is a wide range of energy storage devices and power consumption requirements are very versatile, there are many possible solutions for electronic power devices, but not all of them will be appropriate for each system. One possible solution concerning dc/dc converters is represented by the phase shift operation for full bridge topologies. This procedure is used for supplying the electrical 14 V system from the high voltage energy storage or, in the other direction, charge the HV battery from the 14 V net or even from an external 230 V / 400 ac net. Finepower has developed 2 prototypes for research, which are presented in this contribution. Another new topology, a bidirectional LLC Converter, is presented as well. Energy consumption is growing and the available space for electronic power devices is held very small, so the power density increases and thermal management becomes more difficult. As dimensions of bus bars, semiconductors or inductive components are shrinking, parasitic influence becomes more and more significant. For getting information about function and influence of parasitics of electronic power devices, simulation is a very important tool since it saves much time and gives the possibility to extract internal dimensions of electrical circuits which cannot be measured in reality. (orig.)

  15. A battery-based, low-noise voltage source

    Science.gov (United States)

    Wagner, Anke; Sturm, Sven; Schabinger, Birgit; Blaum, Klaus; Quint, Wolfgang

    2010-06-01

    A highly stable, low-noise voltage source was designed to improve the stability of the electrode bias voltages of a Penning trap. To avoid excess noise and ground loops, the voltage source is completely independent of the public electric network and uses a 12 V car battery to generate output voltages of ±15 and ±5 V. First, the dc supply voltage is converted into ac-voltage and gets amplified. Afterwards, the signal is rectified, filtered, and regulated to the desired output value. Each channel can deliver up to 1.5 A. The current as well as the battery voltage and the output voltages can be read out via a universal serial bus (USB) connection for monitoring purposes. With the presented design, a relative voltage stability of 7×10-7 over 6.5 h and a noise level equal or smaller than 30 nV/√Hz is achieved.

  16. The erigone bus study

    International Nuclear Information System (INIS)

    A study has been made of some factors determining the performance and cost-effectiveness of microcomputer bus systems implemented in Europa crates. An experimental system has been specified and a number of modules constructed in accordance with the specification, in order to test the validity of some of the ideas proposed. It has been demonstrated that the bus interfacing logic can be simple and inexpensive, while maintaining a high degree of processor independence and also a high degree of transparency in operation. The number of pins required by the bus is minimized by multiplexing address and data. A series termination for the drive of the multiplexed lines permits cross-talk to be reduced to insignificant levels: this technique is recommended for wider application. The experimental bus is proposed as a basis for the construction of simple microcomputer-based instrumentation systems. (orig.)

  17. Brazilian hybrid electric fuel cell bus

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, P.E.V.; Carreira, E.S. [Coppe-Federal Univ. of Rio de Janeiro (Brazil). Hydrogen Lab.

    2010-07-01

    The first prototype of a hybrid electric fuel cell bus developed with Brazilian technology is unveiled. It is a 12 m urban-type, low-floor, air-conditioned bus that possesses three doors, air suspension, 29 seats and reversible wheelchair site. The bus body was built based on a double-deck type monoblock vehicle that is able to sustain important load on its roof. This allowed positioning of the type 3 hydrogen tanks and the low weight traction batteries on the roof of the vehicles without dynamic stabilization problems. A novel hybrid energy configuration was designed in such a way that the low-power (77 kWe) fuel cell works on steady-state operation mode, not responding directly to the traction motor load demand. The rate of kinetic energy regeneration upon breaking was optimized by the use of an electric hybrid system with predominance of batteries and also by utilizing supercapacitors. The electric-electronic devices and the security control softwares for the auxiliary and traction systems were developed in-house. The innovative hybrid-electric traction system configuration led to the possibility to decrease the fuel cell power, with positive impact on weight and system volume reduction, as well as to significantly decrease the hydrogen consumption. (orig.)

  18. Bus.py

    Energy Technology Data Exchange (ETDEWEB)

    2014-07-21

    GridLAB-D is an agent? based distribution system simulation environment that allows fine-grained end-user models, including geospatial and network topology detail. GridLAB-D addresses the lack of runtime interaction by designing a flexible communication interface, Bus.py (pronounced bus-dot-pie), that uses Python to pass messages between one or more GridLAB-D instances and a Smart Grid simulator.

  19. 从消费者的视角分析纯电动城市客车的生命周期成本%Analysis on the Whole-life-cycle Cost of Battery Electric City-bus from Consumer Perspective

    Institute of Scientific and Technical Information of China (English)

    吴添; 欧训民; 林成涛

    2012-01-01

    通过应用现值分析理论解决跨期消费问题,建立了纯电动汽车生命周期成本的评价模型,从消费者的视角,对我国纯电动城市客车进行了案例研究,包括空调开启对成本的影响分析.结果表明:目前我国纯电动城市客车的生命周期成本远高于传统柴油车;空调的开启对纯电动城市客车的生命周期成本影响显著.%By applying present value analysis theory to the solving of intertemporal consumption problem, an evaluation model for the whole life cycle cost ( WLCC) of battery electric vehicle is established, and a case study on the battery electric city bus (BEB) including the analysis on the effects of the use of air conditioner on the WLCC of BEB is conducted. The results show that the WLCC of BEB is much higher than that of traditional diesel bus at present, and the use of air conditioner has significant effects on the WLCC of BEB.

  20. LHC on the bus

    CERN Document Server

    Laëtitia Pedroso

    2010-01-01

    On 15 December, an airport bus will be transformed in the image of CERN. The bus will be seen by the thousands of travellers arriving in Geneva, informing them of the possibility to visit CERN.   Sketch of the bus. The good relationship between Geneva International Airport and CERN started several years ago. In 2004 the airport put advertising space in the arrivals area at CERN's disposal free of charge. Now, starting on 15 December, a 40-foot long bus will display a giant sticker advertisement depicting CERN as it takes passengers over the airport tarmac to their planes. This is no ordinary sticker, and it was no mean task to attach it to the bus. The task of producing and attaching it was entrusted to Geneva-based specialists Mathys SA. With the ski season opening on 15 December, there will be many travellers arriving at the airport, and the bus will be ready to receive them. When one thinks of CERN, the subjects that naturally come to mind are the LHC, the mysteries of the Universe...

  1. BUS 660 Ash course tutorial / uophelp

    OpenAIRE

    uophelp

    2015-01-01

      www.uophelp.com         BUS 660 Week 1 Assignment Developing Leaders at UPS BUS 660 Week 2 Assignment Leadership Style BUS 660 Week 3 Assignment Leadership Traits BUS 660 Week 4 Assignment Leadership Skills BUS 660 Week 5 Assignment Big Changes for a Small Hospital BUS 660 Week 6 Assignment Research Paper BUS 660 Week 1 DQ 1 Leadership Defined BUS 660 Week 1 DQ 2 Education and Experience BUS 660 Week 2 DQ 1 Lea...

  2. Lightweight DC-DC Converter with Partial Power Processing and MPPT for a Solar Powered Aircraft

    Science.gov (United States)

    Diab-Marzouk, Ahmad

    A lightweight dc-dc partial power processing converter is demonstrated for solar aerospace applications. A system-level model is conceived to determine conformity to payload and target distance objectives, with the Solarship aircraft used as an application example. The concept of partial power processing is utilized to realize a high efficiency lightweight converter that performs Max Peak Power Tracking (MPPT) to transfer power from the aircraft solar array to the high-voltage battery bus. The isolated Cuk is determined to be a suitable converter topology for the application. A small-signal model is derived for control design. The operation of a 400V, 2.7 kW prototype is verified at high frequency (200 kHz), high efficiency (> 98%), small mass (0.604 kg), and uses no electrolytic capacitors. MPPT operation is verified on a 376 V commercial solar installation at The University of Toronto. The prototype serves as an enabling technology for solar aerospace applications.

  3. Advanced Intelligent System Application to Load Forecasting and Control for Hybrid Electric Bus

    Science.gov (United States)

    Momoh, James; Chattopadhyay, Deb; Elfayoumy, Mahmoud

    1996-01-01

    The primary motivation for this research emanates from providing a decision support system to the electric bus operators in the municipal and urban localities which will guide the operators to maintain an optimal compromise among the noise level, pollution level, fuel usage etc. This study is backed up by our previous studies on study of battery characteristics, permanent magnet DC motor studies and electric traction motor size studies completed in the first year. The operator of the Hybrid Electric Car must determine optimal power management schedule to meet a given load demand for different weather and road conditions. The decision support system for the bus operator comprises three sub-tasks viz. forecast of the electrical load for the route to be traversed divided into specified time periods (few minutes); deriving an optimal 'plan' or 'preschedule' based on the load forecast for the entire time-horizon (i.e., for all time periods) ahead of time; and finally employing corrective control action to monitor and modify the optimal plan in real-time. A fully connected artificial neural network (ANN) model is developed for forecasting the kW requirement for hybrid electric bus based on inputs like climatic conditions, passenger load, road inclination, etc. The ANN model is trained using back-propagation algorithm employing improved optimization techniques like projected Lagrangian technique. The pre-scheduler is based on a Goal-Programming (GP) optimization model with noise, pollution and fuel usage as the three objectives. GP has the capability of analyzing the trade-off among the conflicting objectives and arriving at the optimal activity levels, e.g., throttle settings. The corrective control action or the third sub-task is formulated as an optimal control model with inputs from the real-time data base as well as the GP model to minimize the error (or deviation) from the optimal plan. These three activities linked with the ANN forecaster proving the output to the

  4. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: Fourth Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2013-01-01

    SunLine Transit Agency, which provides public transit services to the Coachella Valley area of California, has demonstrated hydrogen and fuel cell bus technologies for more than 10 years. In May 2010, SunLine began demonstrating the advanced technology (AT) fuel cell bus with a hybrid electric propulsion system, fuel cell power system, and lithium-based hybrid batteries. This report describes operations at SunLine for the AT fuel cell bus and five compressed natural gas buses. The U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is working with SunLine to evaluate the bus in real-world service to document the results and help determine the progress toward technology readiness. NREL has previously published three reports documenting the operation of the fuel cell bus in service. This report provides a summary of the results with a focus on the bus operation from February 2012 through November 2012.

  5. BusTechn

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Introduced the characteristics of series communicat io n I 2C bus and basic communication protocol, and introduced the application of the bus I 2C according to the image sensor OV7610.The computer correspondence s tyle can be divided the parallel correspondence and the series correspondence. T he rate of series correspondence is rapid, and the property of real time is exce llent. Because the number of ports which it takes is great, it is not proper to miniaturize. Whereas the rate of series corresponden...

  6. Learning NServiceBus

    CERN Document Server

    Boike, David

    2013-01-01

    This is a practical tutorial containing hands-on examples for creating a messaging and SOA based service bus.This book is for .NET developers who are looking for ways to overcome problems related to buggy third party web service integrations, codebases that have grown into a big ball of mud, and batch jobs failure.

  7. BUS 401 Ash course tutorial / uophelp

    OpenAIRE

    uophelp

    2015-01-01

    For more course tutorials visit www.uophelp.com   BUS 401 Week 1 DQ 1 Corporate Income Tax and Real Interest Rates BUS 401 Week 1 DQ 2 Cash Flow and Ratio Analysis BUS 401 Week 1 Assignment Ratio Analysis BUS 401 Week 1 Quiz BUS 401 Week 2 DQ 1 Annuity and Capital Asset Pricing BUS 401 Week 2 DQ 2 Bonds and Common Stock BUS 401 Week 2 Assignment Alternative Investments BUS 401 Week 2 Quiz BUS 401 Week 3 DQ 1 NPV, PI, and IRR BUS 401 Week 3 ...

  8. BUS 437 UOP Course Tutorial/ Tutorialrank

    OpenAIRE

    john

    2015-01-01

    For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 4 Times, Rating: A+   ASHFORD BUS 437 Week 1 Assignment Company Description ASHFORD BUS 437 Week 1 DQ 1 Writing the Business Plan ASHFORD BUS 437 Week 1 DQ 2 Using Outside Help to Write the Plan ASHFORD BUS 437 Week 2 Assignment Marketing Section ASHFORD BUS 437 Week 2 DQ 1 Customer Survey ASHFORD BUS 437 Week 2 DQ 2 Industry Analysis ASHFORD BUS 437 Week 3 Assignment Strategy...

  9. 永磁同步电机直流母线能量互馈试验系统设计与实现%Design and Implementation of the DC Bus Reciprocal Power -Fed Testing System for the Permanent Magnet Synchronous Motor

    Institute of Scientific and Technical Information of China (English)

    邱忠才; 魏振兴; 肖建; 葛艳华

    2014-01-01

    A DC bus reciprocal power -fed testing system based on the incremental photoelectric encoder was de -signed in this paper,which included a double inverter and a double permanent magnet synchronous motor (PMSM) withid being 0 vector control.The construction and working principle of this system were discussed , and then the hard-ware design and the technological process of software control were proposed in this paper .The experimental results verified that this experiment system had excellent dynamic and static performances and ideal control effects , which could provide a very good research platform for the study of the PMSM control .%设计了基于增量式光电编码器,采用 id 等于0矢量控制双逆变器双永磁同步电机直流母线能量互馈牵引试验系统。讨论了整个系统的组成和运行原理,给出了硬件设计与软件控制流程。实验结果证明该系统具有良好的静、动态性能和比较理想的控制效果,可以为永磁同步电机控制研究提供研究平台。

  10. Optimization of Performance Characteristics of Hybrid Wind Photovoltaic System with Battery Storage

    Directory of Open Access Journals (Sweden)

    C. Kathirvel

    2014-03-01

    Full Text Available This study concentrates on the Design and Implementation of a multi source hybrid Wind-Photovoltaic stand alone system with proposed energy management strategy. The method of investigation concerned with the definition of the system topology, interconnection of the various sources with maximum energy transfer, optimum control and energy management in order to maintain the DC bus voltage into a fixed value. An Energy management strategy was proposed using the Fuzzy logic controller such that enhancement in the performance of the system and optimization can be done. The Fuzzy logic controller takes the input from Solar (irradiation, Wind (speed, Power demand and the battery voltage which controls the respective subsystem and formulates into different operational modes of energy management. The role of Fuzzy threshold controller is to adjust continuously the threshold value for optimal performance based on expected wind, solar conditions, battery voltage and power demand. It is shown that when the fuzzy logic controller is used, the proposed DC bus voltage regulation strategy with different modes of operation have fast response and efficient operation which leads to a reduced operating cost.

  11. A Novel Degradation Estimation Method for a Hybrid Energy Storage System Consisting of Battery and Double-Layer Capacitor

    Directory of Open Access Journals (Sweden)

    Yuanbin Yu

    2016-01-01

    Full Text Available This paper presents a new method for battery degradation estimation using a power-energy (PE function in a battery/ultracapacitor hybrid energy storage system (HESS, and the integrated optimization which concerns both parameters matching and control for HESS has been done as well. A semiactive topology of HESS with double-layer capacitor (EDLC coupled directly with DC-link is adopted for a hybrid electric city bus (HECB. In the purpose of presenting the quantitative relationship between system parameters and battery serving life, the data during a 37-minute driving cycle has been collected and decomposed into discharging/charging fragments firstly, and then the optimal control strategy which is supposed to maximally use the available EDLC energy is presented to decompose the power between battery and EDLC. Furthermore, based on a battery degradation model, the conversion of power demand by PE function and PE matrix is applied to evaluate the relationship between the available energy stored in HESS and the serving life of battery pack. Therefore, according to the approach which could decouple parameters matching and optimal control of the HESS, the process of battery degradation and its serving life estimation for HESS has been summed up.

  12. A Multi-Level Grid Interactive Bi-directional AC/DC-DC/AC Converter and a Hybrid Battery/Ultra-capacitor Energy Storage System with Integrated Magnetics for Plug-in Hybrid Electric Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Onar, Omer C [ORNL

    2011-01-01

    This study presents a bi-directional multi-level power electronic interface for the grid interactions of plug-in hybrid electric vehicles (PHEVs) as well as a novel bi-directional power electronic converter for the combined operation of battery/ultracapacitor hybrid energy storage systems (ESS). The grid interface converter enables beneficial vehicle-to-grid (V2G) interactions in a high power quality and grid friendly manner; i.e, the grid interface converter ensures that all power delivered to/from grid has unity power factor and almost zero current harmonics. The power electronic converter that provides the combined operation of battery/ultra-capacitor system reduces the size and cost of the conventional ESS hybridization topologies while reducing the stress on the battery, prolonging the battery lifetime, and increasing the overall vehicle performance and efficiency. The combination of hybrid ESS is provided through an integrated magnetic structure that reduces the size and cost of the inductors of the ESS converters. Simulation and experimental results are included as prove of the concept presenting the different operation modes of the proposed converters.

  13. Isolated DC-DC UPS based in a forward-forward converter analysis and design

    OpenAIRE

    García Suárez, Oscar; Flores Oropeza, Luis Alejandro; Román Loera, Alejandro; Esparza González, Mario S.

    2008-01-01

    This paper presents the analysis, design and simulation from a simple DC-UPS converter with integrated back-up and automatic transition. This converter makes automatic transition between the main AC and the battery when a failure occurs, and it delivers uninterrupted DC power to the load through two independent power sources of commercial input power and battery power. The converter has the following characteristics: automatic transition between the main and the battery, no additional control...

  14. BUS 402 Ash course tutorial / uophelp

    OpenAIRE

    uophelp-

    2015-01-01

    For more course tutorials visit www.uophelp.com     BUS 402 Week 1 DQ 1 Environmental Changes BUS 402 Week 1 DQ 2 Vision and Mission BUS 402 Week 2 DQ 1 Components of External Environment  BUS 402 Week 2 DQ 2 Components of Internal Analysis BUS 402 Week 2 Assignment Starbucks S.W.O.T. Analysis BUS 402 Week 3 DQ 1 Market Positioning Strategies BUS 402 Week 3 DQ 2 Vertical Integration BUS 402 Week 4 DQ 1 International Markets BUS 40...

  15. BUS 642 Ash course tutorial / uophelp

    OpenAIRE

    uophelp

    2015-01-01

    www.uophelp.com     BUS 642 Week 1 DQ 1 Scientific Thinking (Ash Course) BUS 642 Week 1 DQ 2 Making Research Decisions (Ash Course) BUS 642 Week 1 Exercises (Ash Course) BUS 642 Week 2 DQ 1 Ethics in Business Research (Ash Course) BUS 642 Week 2 DQ 2 Design of Research (Ash Course) BUS 642 Week 2 Exercises (Ash Course) BUS 642 Week 3 DQ 1 Measurement Scales (Ash Course) BUS 642 Week 3 DQ 2 Clarifying the Research Questions (Ash Course) BUS...

  16. BUS 437 Ash course tutorial / uophelp

    OpenAIRE

    uophelp

    2015-01-01

    For more course tutorials visit www.uophelp.com   BUS 437 Week 1 Assignment Company Description BUS 437 Week 1 DQ 1 Writing the Business Plan BUS 437 Week 1 DQ 2 Using Outside Help to Write the Plan BUS 437 Week 2 Assignment Marketing Section BUS 437 Week 2 DQ 1 Customer Survey BUS 437 Week 2 DQ 2 Industry Analysis BUS 437 Week 3 Assignment Strategy, Implementation, & Management Sections BUS 437 Week 3 DQ 1 Implementation BUS 437 Week 3 DQ ...

  17. 基于LIN总线的阀控式铅酸蓄电池管理系统设计%Design of valve regulated lead-acid battery management system based on LIN bus

    Institute of Scientific and Technical Information of China (English)

    朴昌浩; 刘其峰; 黄智宇; 刘明亮

    2011-01-01

    电池管理系统作为电动汽车重要的组成部件之一,被广泛地用于汽车电池组管理中,来确保电池的高性能、高可靠性和高稳定性.电池管理系统能够保护电池免受破坏,预测电池寿命以及在电池工作的情况下维护和保养电池.由于铅酸蓄电池充放电过程的复杂性和非线性,采用非线性最小二乘法回归得到电池的初始荷电状态.针对阀控式铅酸蓄电池,设计了基于本地互联网络的电池管理系统,在此基础上利用片上卡尔曼滤波算法对电池荷电状态进行在线修正.同时,介绍了电压采集模块,电流采集模块,温度采集模块,通信电路模块.验证试验结果表明,当电池荷电状态处于30%~70%范围内时,荷电状态平均相对误差为3%左右.%Battery management system (BMS), as one of important component in electric vehicle, is widely used in automotive battery management in order to ensure performance, high reliability and high stability. BMS can prevent battery from damage, predict battery state of health, and maintain battery in work condition. Due to the complex and nonlinear electrochemical process of lead-acid battery in charging and discharging, the initial battery state of charge (SOC) was obtained by non-linear least squares regression method (NLLSRM) in the paper. For valve regulated lead-acid battery (VRLA), a battery management system based on local interconnect network (LIN) was designed and on chip Kalman filter algorithm was employed to correct SOC on-line. At the same time, a detailed hardware circuit schemes of primary modules was introduced, including voltage sampling module, current sampling module, temperature sampling module, data transfer module. The validation experimental results show that the proposed lead-acid battery control unit is high credible and the SOC estimation average relative error is about 3% when the battery is 30%SOC to 70%SOC status.

  18. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Third Evaluation Report and Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2010-01-01

    This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. The prototype fuel cell bus was manufactured by Van Hool and ISE Corp. and features an electric hybrid drive system with a UTC Power PureMotion 120 Fuel Cell Power System and ZEBRA batteries for energy storage. The fuel cell bus started operation in April 2007, and evaluation results through October 2009 are provided in this report.

  19. 77 FR 48592 - Bus and Bus Facilities Discretionary Program Funds

    Science.gov (United States)

    2012-08-14

    ... authorized by 49 U.S.C. 5309(b), as amended by Section 3011 of the Safe, Affordable, Flexible, Efficient... Livability Initiatives (77 FR 6178). The NOFA explained the requirements and procedures for eligible... facilities, bus-related equipment, and transit asset management systems. The FY 2012 Bus...

  20. Design and implementation of low-ripple dual battery DC regulated power supply%低纹波双电池直流稳压电源设计与实现

    Institute of Scientific and Technical Information of China (English)

    李杰; 程为彬; 冯笃; 满荣娟

    2016-01-01

    为实现供电电源的低纹波输出,采用纹波控制方法,设计了一种双电池充供欠满自主切换的低纹波直流电源,并对电源进行纹波特性测试。原始信号通过电压采集电路传输给控制主电路,控制主电路依据采集到的电压信号和继电器开关的通断原则来控制充供电选择电路,可供电电池通过线性电压调整电路即可实现一路5V和两路可调电压输出,实现了从充电到供电的低纹波直流稳压输出。电源纹波测试采用同轴电缆测试装置,测试数据表明:低纹波直流稳压电源运行状况良好,输出电压稳定,与其他直流电源相比,在纹波控制方面具有较大优势。%In order to realize the low⁃ripple output of the power supply,a low⁃ripple dual battery DC power supply was de⁃signed with the ripple control method,which can switch from the low power state to full power state automatically. The ripple characteristic test for the power supply was performed. The original signal is transmitted to the main control circuit through the voltage acquisition circuit,and then the main control circuit is used to control the charging and supplying power selection circuit according to the on⁃off principle of the relay switch and collected voltage signal. The power supply battery can realize +5V volt⁃age output in one channel and adjustable voltage output in two channels through the linear voltage adjustment circuit. The low ripple DC voltage regulator output from charging state to supplying power state was implemented. A coaxial⁃cable testing device was adopted in power supply ripple test. The test data shows that the low ripple DC regulated power supply has good running condition and greater advantage in ripple control in combination with other DC power supply,and its output voltage is stable.

  1. BUS 611 Ash course tutorial / uophelp

    OpenAIRE

    uophelp

    2015-01-01

    For more course tutorials visit www.uophelp.com   BUS 611 Week 1 Assignment Article Review (Ash Course) BUS 611 Week 2 Assignment Project Risk (Ash Course) BUS 611 Week 3 Assignment WBS (Ash Course) BUS 611 Week 4 Assignment Integrated Project Management Tools (Ash Course) BUS 611 Week 5 Assignment Monthly Status Reports (Ash Course) BUS 611 Week 6 Final Research Paper (Ash Course)  

  2. Dual-Input Isolated Full-Bridge Boost DC-DC Converter Based on the Distributed Transformers

    DEFF Research Database (Denmark)

    Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.;

    2012-01-01

    , so the proposed converter can draw the power from the two different dc sources, which have low output voltage, and transfer it to the dc bus, which has high voltage, separately or simultaneously. The detailed operation principles of the proposed converter have been analyzed in the dual-input mode...

  3. Robust DC/DC converter control for polymer electrolyte membrane fuel cell application

    Science.gov (United States)

    Wang, Ya-Xiong; Yu, Duck-Hyun; Chen, Shi-An; Kim, Young-Bae

    2014-09-01

    This study investigates a robust controller in regulating the pulse width modulation (PWM) of a DC/DC converter for a polymer electrolyte membrane fuel cell (PEMFC) application. A significant variation in the output voltage of a PEMFC depends on the power requirement and prevents a PEMFC from directly connecting to a subsequent power bus. DC/DC converters are utilized to step-up or step-down voltage to match the subsequent power bus voltage. In this study, a full dynamic model, which includes a PEMFC and boost and buck DC/DC converters, is developed under MATLAB/Simulink environment for control. A robust PWM duty ratio control for the converters is designed using time delay control (TDC). This control enables state variables to accurately follow the dynamics of a reference model using time-delayed information of plant input and output information within a few sampling periods. To prove the superiority of the TDC performance, traditional proportional-integral control (PIC) and model predictive control (MPC) are designed and implemented, and the simulation results are compared. The efficacies of TDC for the PEMFC-fed PWM DC/DC converters are validated through experimental test results using a 100 W PEMFC as well as boost and buck DC/DC converters.

  4. Design of the HEAO main bus shunt regulator. [High Energy Astronomical Observatory solar array

    Science.gov (United States)

    Middlebrook, R. D.; Kimble, S. G.

    1976-01-01

    The High Energy Astronomy Observatory (HEAO) is being built for NASA by an American company. The general requirements concerning the HEAO main bus regulator are examined. The bus regulated voltage is 33 V, the maximum shunt current is 45 A, and the regulator output impedance is to be less than 0.5 Ohm from dc to 100 kHz. Loop gain design considerations for the main bus regulator are discussed and a description is given of the general device configuration. Attention is also given to regulator loop design and performance.

  5. BUS 620 Ash course tutorial / uophelp

    OpenAIRE

    uophelp

    2015-01-01

    For more course tutorials visit www.uophelp.com   BUS 620 Week 1 DQ 1 What is Marketing (Ash Course) BUS 620 Week 1 DQ 2 Marketing Strategies (Ash Course) BUS 620 Week 1 The Future of the New York Times (Ash Course) BUS 620 Week 2 DQ 1 Buyer Behavior (Ash Course) BUS 620 Week 2 DQ 2 Customer Needs (Ash Course) BUS 620 Week 2 Industry Forecasting (Ash Course) BUS 620 Week 3 DQ 1 Braining Nordstrom (Ash Course) BUS 620 Week 3 DQ 2 Marketing Segmentat...

  6. Learning NServiceBus Sagas

    CERN Document Server

    Helton, Rich

    2015-01-01

    If you are an Enterprise C# developer who wishes to extend your knowledge of NServiceBus and Enterprise Service Bus in C#, this is the book for you. This book is designed to enhance the education of ESBs and their messaging, whether you are a beginner or a seasoned expert in Enterprise C#, Apex, and Visualforce pages.

  7. An Integrated Multifunctional Bidirectional AC/DC and DC/DC Converter for Electric Vehicles Applications

    Directory of Open Access Journals (Sweden)

    Liwen Pan

    2016-06-01

    Full Text Available This paper presents an on-board vehicular battery charger that integrates bidirectional AC/DC converter and DC/DC converter to achieve high power density for application in electric vehicles (EVs. The integrated charger is able to transfer electrical energy between the battery pack and the electric traction system and to function as an AC/DC battery charger. The integrated charger topology is presented and the design of passive components is discussed. The control schemes are developed for motor drive system and battery-charging system with a power pulsation reduction circuit. Simulation results in MATLAB/Simulink and experiments on a 30-kW motor drive and 3.3-kW AC/DC charging prototype validate the performance of the proposed technology. In addition, power losses, efficiency comparison and thermal stress for the integrated charger are illustrated. The results of the analyses show the validity of the advanced integrated charger for electric vehicles.

  8. Standard satellite data bus initiative

    Science.gov (United States)

    Spinney, Timothy; Yousef, Hassan

    The USAF Space Technology Center manages programs to reduce satellite costs through the appropriate use of microelectronics standardization. Ongoing programs such as the Standard Spacecraft Memory Module and Generic VHSIC Spaceborne Computer have provided an insight into the value of standardization and led to an initiative to coordinate microelectronics development around a standard satellite data bus, which should reduce costs by eliminating program- and contractor-unique interfaces, increasing production runs, and developing generic test equipment. Current efforts focus on the satellite housekeeping functions, and it is expected that the mission payload would also use this data bus. Based on existing housekeeping data-traffic requirements, several candidates have been identified for the standard data bus. The two candidates selected for further work are the ANSI X3T9.5 data bus and the linear token-passing data bus being proposed as part of the Advanced Tactical Fighter effort.

  9. Bi-Directional DC-DC Converter for PHEV Applications

    Energy Technology Data Exchange (ETDEWEB)

    Abas Goodarzi

    2011-01-31

    Plug-In Hybrid Electric Vehicles (PHEV) require high power density energy storage system (ESS) for hybrid operation and high energy density ESS for Electric Vehicle (EV) mode range. However, ESS technologies to maximize power density and energy density simultaneously are not commercially feasible. The use of bi-directional DC-DC converter allows use of multiple energy storage, and the flexible DC-link voltages can enhance the system efficiency and reduce component sizing. This will improve fuel consumption, increase the EV mode range, reduce the total weight, reduce battery initial and life cycle cost, and provide flexibility in system design.

  10. The Myth of the "Ideal Bus"

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Does as an ideal bus technology exist? Many companies have and will promote a single technology as the ideal bus that will meet all application needs, but in actuality, each bus technology has its own strengths and weaknesses and thus is appropriate for different applications. History has shown the folly of claiming an ideal bus for every application.

  11. A Bidirectional Multi-Port DC-DC Converter Integrating Voltage Equalizer

    DEFF Research Database (Denmark)

    Chen, Jianfei; Hou, Shiying; Deng, Fujin;

    2015-01-01

    A novel bidirectional multi-port dc-dc converter integrating voltage equalizer based on switched-capacitor voltage accumulator (SCVA) is proposed. It has two operating modes of charging and discharging for battery modules. All battery modules are connected in series indirectly and can be equalized...... with a uniform voltage level while eliminating the voltage imbalance. In addition, high step-down and step-up ratios with low component voltage stress can be achieved in the proposed converter. A bidirectional four-port dc-dc converter is presented to do theoretical analysis for the voltage equalization of three...

  12. High-Speed Ring Bus

    Science.gov (United States)

    Wysocky, Terry; Kopf, Edward, Jr.; Katanyoutananti, Sunant; Steiner, Carl; Balian, Harry

    2010-01-01

    The high-speed ring bus at the Jet Propulsion Laboratory (JPL) allows for future growth trends in spacecraft seen with future scientific missions. This innovation constitutes an enhancement of the 1393 bus as documented in the Institute of Electrical and Electronics Engineers (IEEE) 1393-1999 standard for a spaceborne fiber-optic data bus. It allows for high-bandwidth and time synchronization of all nodes on the ring. The JPL ring bus allows for interconnection of active units with autonomous operation and increased fault handling at high bandwidths. It minimizes the flight software interface with an intelligent physical layer design that has few states to manage as well as simplified testability. The design will soon be documented in the AS-1393 standard (Serial Hi-Rel Ring Network for Aerospace Applications). The framework is designed for "Class A" spacecraft operation and provides redundant data paths. It is based on "fault containment regions" and "redundant functional regions (RFR)" and has a method for allocating cables that completely supports the redundancy in spacecraft design, allowing for a complete RFR to fail. This design reduces the mass of the bus by incorporating both the Control Unit and the Data Unit in the same hardware. The standard uses ATM (asynchronous transfer mode) packets, standardized by ITU-T, ANSI, ETSI, and the ATM Forum. The IEEE-1393 standard uses the UNI form of the packet and provides no protection for the data portion of the cell. The JPL design adds optional formatting to this data portion. This design extends fault protection beyond that of the interconnect. This includes adding protection to the data portion that is contained within the Bus Interface Units (BIUs) and by adding to the signal interface between the Data Host and the JPL 1393 Ring Bus. Data transfer on the ring bus does not involve a master or initiator. Following bus protocol, any BIU may transmit data on the ring whenever it has data received from its host. There

  13. Hybrid fuel cell bus demonstration: advanced technology moves bus forward

    International Nuclear Information System (INIS)

    The Province of Manitoba has been actively pursuing hydrogen since 2001 as one part of a portfolio of renewable energy alternatives. Six priority hydrogen actions have been underway covering a variety of opportunities, including two recently completed major transit bus and refueling demonstrations. A brief overview of Manitoba's activities on hydrogen will be provided, emphasizing the lessons learned from recent projects such as the hydrogen Hybrid Fuel Cell Bus demonstration, and in particular implications for the research community. (author)

  14. BUS 402 UOP Course Tutorial/ Tutorialrank

    OpenAIRE

    jonh

    2015-01-01

    For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 4 Times, Rating: A+   ASHFORD BUS 402 Week 1 DQ 1 Environmental Changes ASHFORD BUS 402 Week 1 DQ 2 Vision and Mission ASHFORD BUS 402 Week 2 DQ 1 Components of External Environment ASHFORD BUS 402 Week 2 DQ 2 Components of Internal Analysis ASHFORD BUS 402 Week 2 Assignment Starbucks S.W.O.T. Analysis ASHFORD BUS 402 Week 3 DQ 1 Market Positioning Strategies ASHFORD BUS 402 W...

  15. Mono-switch AC-DC/DC-DC converter for single-phase UPS%单相UPS的单开关AC-DC/DC-DC变换电路

    Institute of Scientific and Technical Information of China (English)

    李宋; 叶满园; 袁义生

    2011-01-01

    A mono-switch AC-DC/DC-DC converter used in single-phase UPS system is introduced,which consists of one power switch and six diodes. As both AC-DC rectifier and DC-DC booster,its operating modes and working principle are detailed. The single-cycle nonlinear control is adopted,which applies two low-speed PI regulators to control the voltage of two capacitors on DC link and a high-speed PI regulator to control the input current. Simulative results prove that,being simple and reliable,it outputs stable DC bus voltage with high input power factor and low THD.%介绍了一种应用在单相UPS系统中的新型单开关AC-DC/DC-DC变换电路,该电路由1个功率开关器件和6个二极管组成,能够实现AC/DC整流和DC/DC升压2种功能.在详细分析了该电路运行模式及工作原理的基础上,采用了单周期非线性控制理论对其进行控制,利于2个低速PI调节器对直流母线上的2个电容器电压进行控制,1个高速PI调节器对输入电流进行控制.仿真结果表明,该电路简单可靠,输入功率因数高,电流谐波失真小,可以获得稳定的正负直流母线电压.

  16. BUS 501 Str course tutorial / uophelp

    OpenAIRE

    uophel

    2015-01-01

    For more course tutorials visit www.uophelp.com     BUS 501 Week 3 Assignment 1 The Independent Government Cost Estimate and the Statement of Work (Str Course) BUS 501 Week 4 Assignment 2 Types of Contracts and Performance-Based Acquisition (Str Course) BUS 501 Week 7 Assignment 3 Small Business Program and Source Selection Plans (Str Course) BUS 501 Assignment 4 Technical and Cost or Price Evaluations and Price Reasonableness (Str Course) BUS 501 Wee...

  17. BUS 599 Str course tutorial / uophelp

    OpenAIRE

    uophelp

    2015-01-01

    For more course tutorials visit www.uophelp.com   BUS 599 Week 1 Assignment Crafting and Executing Strategy Case JetBlue Airways BUS 599 Assignment #2 Competitive Forces and SWOT Analysis # Case Whole Foods Market BUS 599 Week 3 Assignment Foreign Market Entry and Diversification Case Corona Beer BUS 599 Week 4 Assignment HRM Issues Diversification Strategies Case Nucor Corporation BUS 599 Week 5 Assignment Corporate Culture Leadership Actions for Strategy Imp...

  18. SCHOOL BUS GARAGES, 1966 REVISION.

    Science.gov (United States)

    JOHNSON, HERBERT F.

    STANDARDS AND RECOMMENDATIONS ARE GIVEN FOR THE DESIGN AND CONSTRUCTION OF SCHOOL BUS GARAGES INCLUDING BRIEF DISCUSSIONS OF--(1) SITE DEVELOPMENT, (2) DESIGN AND CONSTRUCTION, AND (3) MECHANICAL (HEATING, PLUMBING, AND VENTILATION) AND ELECTRICAL FACTORS. (JT)

  19. International Space Station Bus Regulation With NASA Glenn Research Center Flywheel Energy Storage System Development Unit

    Science.gov (United States)

    Kascak, Peter E.; Kenny, Barbara H.; Dever, Timothy P.; Santiago, Walter; Jansen, Ralph H.

    2001-01-01

    An experimental flywheel energy storage system is described. This system is being used to develop a flywheel based replacement for the batteries on the International Space Station (ISS). Motor control algorithms which allow the flywheel to interface with a simplified model of the ISS power bus, and function similarly to the existing ISS battery system, are described. Results of controller experimental verification on a 300 W-hr flywheel are presented.

  20. Hydrogen Bus Technology Validation Program

    OpenAIRE

    Burke, Andy; McCaffrey, Zach; Miller, Marshall; Collier, Kirk; Mulligan, Neal

    2005-01-01

    Heavy duty engines are substantial contributors to NOX and PM emissions inventories in urban areas, and stringent emissions standards have been adopted as a consequence. CARB has passed very strict emissions standards for heavy duty engines beginning in 2007. Meeting these standards, especially for NOX emissions, may be difficult for conventional transit bus technologies. The purpose of the Hydrogen Bus Technology Evaluation Program was to develop and evaluate hydrogen enriched natural gas (H...

  1. Advanced DC/DC converters

    CERN Document Server

    Luo, Fang Lin

    2003-01-01

    INTRODUCTIONHistorical ReviewMultiple Quadrant ChoppersPump CircuitsDevelopment of DC/DC Conversion TechniqueCategorize Prototypes and DC/DC Converters Family TreeVOLTAGE-LIFT CONVERTERSIntroductionSeven Self-Lift ConvertersPositive Output Luo-ConvertersNegative Output Luo-ConvertersModified Positive Output Luo-Converters Double Output Luo-ConvertersPOSITIVE OUTPUT SUPER-LIFT LUO-CONVERTERS IntroductionMain SeriesAdditional SeriesEnhanced Series Re-Enhanced Series Multiple-Enhanced Series Summary of Positive Output

  2. Bus Stop - Environment Connection: Do Characteristics of the Built Environment Correlate with Bus Stop Crime?

    OpenAIRE

    Robin S Liggett; Loukaitou-Sideris, Anastasia; Iseki, Hiroyuki

    2003-01-01

    Can we understand why some bus stops are safe and others are crime-ridden? Can we predict which features of the bus stop environment are likely to encourage or discourage crime? Can we design safer bus stops? These questions are addressed by exploring the relationship between environmental variables and bus stop crime. An earlier study used crime data, along with environmental indicators, for a sample of 60 bus stops in downtown Los Angeles. Crime rates were higher for bus stops near alleys, ...

  3. Formation of Sn-M (M=Fe, Al, Ni) alloy nanoparticles by DC arc-discharge and their electrochemical properties as anodes for Li-ion batteries

    Science.gov (United States)

    Gao, Song; Huang, Hao; Wu, Aimin; Yu, Jieyi; Gao, Jian; Dong, Xinglong; Liu, Chunjing; Cao, Guozhong

    2016-10-01

    A direct current arc-discharge method was applied to prepare the Sn-M (M=Fe, Al, Ni) bi-alloy nanoparticles. Thermodynamic is introduced to analyze the energy circumstances for the formation of the nanoparticles during the physical condensation process. The electrochemical properties of as-prepared Sn-M alloy nanoparticles are systematically investigated as anodes of Li-ion batteries. Among them, Sn-Fe nanoparticles electrode exhibits high Coulomb efficiency (about 71.2%) in the initial charge/discharge (257.9 mA h g-1/366.6 mA h g-1) and optimal cycle stability (a specific reversible capacity of 240 mA h g-1 maintained after 20 cycles) compared with others. Large differences in the electrochemical behaviors indicate that the chemical composition and microstructure of the nanoparticles determine the lithium-ion storage properties and the long-term cyclic stability during the charge/discharge process.

  4. COMPARISON OF PARALLEL AND SERIES HYBRID POWERTRAINS FOR TRANSIT BUS APPLICATION

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Zhiming [ORNL; Daw, C Stuart [ORNL; Smith, David E [ORNL; Jones, Perry T [ORNL; LaClair, Tim J [ORNL; Parks, II, James E [ORNL

    2016-01-01

    The fuel economy and emissions of both conventional and hybrid buses equipped with emissions aftertreatment were evaluated via computational simulation for six representative city bus drive cycles. Both series and parallel configurations for the hybrid case were studied. The simulation results indicate that series hybrid buses have the greatest overall advantage in fuel economy. The series and parallel hybrid buses were predicted to produce similar CO and HC tailpipe emissions but were also predicted to have reduced NOx tailpipe emissions compared to the conventional bus in higher speed cycles. For the New York bus cycle (NYBC), which has the lowest average speed among the cycles evaluated, the series bus tailpipe emissions were somewhat higher than they were for the conventional bus, while the parallel hybrid bus had significantly lower tailpipe emissions. All three bus powertrains were found to require periodic active DPF regeneration to maintain PM control. Plug-in operation of series hybrid buses appears to offer significant fuel economy benefits and is easily employed due to the relatively large battery capacity that is typical of the series hybrid configuration.

  5. Wishbone bus Architecture - A Survey and Comparison

    CERN Document Server

    Sharma, Mohandeep; 10.5121/vlsic.2012.3210

    2012-01-01

    The performance of an on-chip interconnection architecture used for communication between IP cores depends on the efficiency of its bus architecture. Any bus architecture having advantages of faster bus clock speed, extra data transfer cycle, improved bus width and throughput is highly desirable for a low cost, reduced time-to-market and efficient System-on-Chip (SoC). This paper presents a survey of WISHBONE bus architecture and its comparison with three other on-chip bus architectures viz. Advanced Micro controller Bus Architecture (AMBA) by ARM, CoreConnect by IBM and Avalon by Altera. The WISHBONE Bus Architecture by Silicore Corporation appears to be gaining an upper edge over the other three bus architecture types because of its special performance parameters like the use of flexible arbitration scheme and additional data transfer cycle (Read-Modify-Write cycle). Moreover, its IP Cores are available free for use requiring neither any registration nor any agreement or license.

  6. DC/DC converter with improved rectification for higher efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Maisel, Peter; Saliternig, Martin [Continental AG, Nuernberg (Germany)

    2010-07-01

    High-power dc-dc converters are an important element of the electrical system of electric vehicles and hybrid electric vehicles. These complex modular components provide the link between the high-voltage level used for the powertrain and the low-voltage bus for the lighting system, engine management and auxiliary needs in the vehicle. The essential requirements for all converters are high efficiency, compact size, lightweight and reliability. A very popular method to increase the efficiency is the synchronous rectification. Parasitic inductances in the commutation circuit and reverse recovery effects can produce a ringing with voltage overshoots at the diodes and the transistors. These spikes can cause higher average power dissipation in the seminconductors and higher EMI (electromagnetic interference).

  7. BUS 210 UOP Course Tutorial/ Tutorialrank

    OpenAIRE

    john

    2015-01-01

                      For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 6 Times, Rating: A+   BUS 210 Week 1 DQ1 and DQ2 (UOP Course) BUS 210 Week 1 Checkpoint Business Models and Systems (UOP Course) BUS 210 Week 2 CheckPoint Business Organization (UOP Course) BUS 210 Week 2 Assignment Evolution of Business Presentation (UOP Course) BUS 210 Week 3 DQ 1 and DQ 2 (UOP Course) BUS 210 W...

  8. Design and Implementation of Digital Current Mode Controller for DC-DC Converters

    DEFF Research Database (Denmark)

    Taeed, Fazel

    In the recent decades, shortage of fossil fuels and global warming have increased the demand for renewable energy resources. Dc-dc converters are widely used in renewable energy systems, electric vehicles, and battery chargers. In practical applications, dc-dc converters are required to be regula......In the recent decades, shortage of fossil fuels and global warming have increased the demand for renewable energy resources. Dc-dc converters are widely used in renewable energy systems, electric vehicles, and battery chargers. In practical applications, dc-dc converters are required...... to be regulated by a closed-loop controller. The Peak Current Mode Control (PCMC) is one of the most promising control methods for dc-dc converters. It has been known for high bandwidth (speed), and inherent current protection. Increasing the controller bandwidth decreases the output filter size and cost. Analog....... Analyzing the obtained model reveals that the small values of capacitor and inductor ESR results in a large resonance peak of complex poles in the voltage to duty cycle transfer function. High efficiency dc-dc converters essentially have low ESR in the capacitor and the inductor. Since the complex poles...

  9. Photovoltaic Electricity for Sustainable Building. Efficiency and Energy Cost Reduction for Isolated DC Microgrid

    OpenAIRE

    Manuela Sechilariu; Fabrice Locment; Baochao Wang

    2015-01-01

    In the context of sustainable buildings, this paper investigates power flow management for an isolated DC microgrid and focuses on efficiency and energy cost reduction by optimal scheduling. Aiming at high efficiency, the local produced power has to be used where, when, and how it is generated. Thus, based on photovoltaic sources, storage, and a biofuel generator, the proposed DC microgrid is coupled with the DC distribution network of the building. The DC bus distribution maximizes the effic...

  10. Triple voltage dc-to-dc converter and method

    Energy Technology Data Exchange (ETDEWEB)

    Su, Gui-Jia (Knoxville, TN)

    2008-08-05

    A circuit and method of providing three dc voltage buses and transforming power between a low voltage dc converter and a high voltage dc converter, by coupling a primary dc power circuit and a secondary dc power circuit through an isolation transformer; providing the gating signals to power semiconductor switches in the primary and secondary circuits to control power flow between the primary and secondary circuits and by controlling a phase shift between the primary voltage and the secondary voltage. The primary dc power circuit and the secondary dc power circuit each further comprising at least two tank capacitances arranged in series as a tank leg, at least two resonant switching devices arranged in series with each other and arranged in parallel with the tank leg, and at least one voltage source arranged in parallel with the tank leg and the resonant switching devices, said resonant switching devices including power semiconductor switches that are operated by gating signals. Additional embodiments having a center-tapped battery on the low voltage side and a plurality of modules on both the low voltage side and the high voltage side are also disclosed for the purpose of reducing ripple current and for reducing the size of the components.

  11. Aids to School Bus Design

    Science.gov (United States)

    1991-01-01

    Navistar International Transportation Corporation, Chicago, IL, used three separate NASA-developed technologies in the design and testing of their 3000 Series Bus Chassis which was developed expressly for school bus applications. For structural analysis, they used the MSC/NASTRAN program which mathematically analyzes a design and predicts how it will hold up under stress. They also used the SPATE 9000 system for non-contact measurement of stress, load transfer mechanisms, detection of hidden flaws, and monitoring structural changes during fatigue testing. SPATE 9000 was based on infrared stress measurement technology developed by Langley Research Center. They also employed the Wyle Ride Quality Meter, which was developed by Langley to aid in passenger aircraft design by providing an accurate measurement of ride vibration and sound level. These numbers translate into a subjective discomfort level index. These technologies contribute to the company's 45-48 percent share of the school bus chassis market.

  12. DC Voltage Balance Control Strategy for Medium Voltage Cascaded STATCOM Based on Distributed Control

    Directory of Open Access Journals (Sweden)

    Xuehua Zhao

    2014-01-01

    Full Text Available DC bus capacitors of Medium Voltage Cascaded STATCOM are independent. DC side voltage balance control method is the key influencing factor of current control. The imbalance of DC bus voltage increases harmonic current and affects the safety of device. In this paper, the unbalance mechanism of DC side capacitor voltage is analyzed. Based on the unipolar dual frequency and carrier phase-shifted SPWM (CPS-SPWM modulation algorithms, the distributed control algorithms, which need multi- FPGA structure, are proposed. By changing the instantaneous active power input of single module, the voltage balance control strategies of DC bus capacitors are realized. The strategy can be applied in each inverter, respectively. Simulation and experiment results show the feasibility and effectiveness of the strategy

  13. Real life testing of a Hybrid PEM Fuel Cell Bus

    Science.gov (United States)

    Folkesson, Anders; Andersson, Christian; Alvfors, Per; Alaküla, Mats; Overgaard, Lars

    Fuel cells produce low quantities of local emissions, if any, and are therefore one of the most promising alternatives to internal combustion engines as the main power source in future vehicles. It is likely that urban buses will be among the first commercial applications for fuel cells in vehicles. This is due to the fact that urban buses are highly visible for the public, they contribute significantly to air pollution in urban areas, they have small limitations in weight and volume and fuelling is handled via a centralised infrastructure. Results and experiences from real life measurements of energy flows in a Scania Hybrid PEM Fuel Cell Concept Bus are presented in this paper. The tests consist of measurements during several standard duty cycles. The efficiency of the fuel cell system and of the complete vehicle are presented and discussed. The net efficiency of the fuel cell system was approximately 40% and the fuel consumption of the concept bus is between 42 and 48% lower compared to a standard Scania bus. Energy recovery by regenerative braking saves up 28% energy. Bus subsystems such as the pneumatic system for door opening, suspension and brakes, the hydraulic power steering, the 24 V grid, the water pump and the cooling fans consume approximately 7% of the energy in the fuel input or 17% of the net power output from the fuel cell system. The bus was built by a number of companies in a project partly financed by the European Commission's Joule programme. The comprehensive testing is partly financed by the Swedish programme "Den Gröna Bilen" (The Green Car). A 50 kW el fuel cell system is the power source and a high voltage battery pack works as an energy buffer and power booster. The fuel, compressed hydrogen, is stored in two high-pressure stainless steel vessels mounted on the roof of the bus. The bus has a series hybrid electric driveline with wheel hub motors with a maximum power of 100 kW. Hybrid Fuel Cell Buses have a big potential, but there are

  14. School bus and children's traffic safety

    Institute of Scientific and Technical Information of China (English)

    PAN Shu-ming; Stephen Hargarten; ZHU Shan-kuan

    2007-01-01

    There is no safer way to transport a child than a school bus. Fatal crashes involving occupants are extremely rare events in the US. In recent years, school bus transportation began to develop in China. We want to bring advanced experience on school bus safety in Western countries such as the US to developing countries.Methods: We searched the papers related to school bus safety from Medline, Chinese Scientific Journals Database and the Web of the National Highway Traffic Safety Administration (NHTSA).Results: There were only 9 papers related to school bus safety, which showed that higher levels of safety standards on school buses, school bus-related transportation and environmental laws and injury prevention were the primary reasons for the desired outcome. Few school bus is related to deaths and injuries in the developed countries.Conclusions: The developing countries should make strict environmental laws and standards on school bus safety to prevent children's injury and death.

  15. A suitable model plant for control of the set fuel cell-DC/DC converter

    Energy Technology Data Exchange (ETDEWEB)

    Andujar, J.M.; Segura, F.; Vasallo, M.J. [Departamento de Ingenieria Electronica, Sistemas Informaticos y Automatica, E.P.S. La Rabida, Universidad de Huelva, Ctra. Huelva - Palos de la Frontera, S/N, 21819 La Rabida - Palos de la Frontera Huelva (Spain)

    2008-04-15

    In this work a state and transfer function model of the set made up of a proton exchange membrane (PEM) fuel cell and a DC/DC converter is developed. The set is modelled as a plant controlled by the converter duty cycle. In addition to allow setting the plant operating point at any point of its characteristic curve (two interesting points are maximum efficiency and maximum power points), this approach also allows the connection of the fuel cell to other energy generation and storage devices, given that, as they all usually share a single DC bus, a thorough control of the interconnected devices is required. First, the state and transfer function models of the fuel cell and the converter are obtained. Then, both models are related in order to achieve the fuel cell+DC/DC converter set (plant) model. The results of the theoretical developments are validated by simulation on a real fuel cell model. (author)

  16. HERMES travels by CAN bus

    Science.gov (United States)

    Waller, Lewis G.; Shortridge, Keith; Farrell, Tony J.; Vuong, Minh; Muller, Rolf; Sheinis, Andrew I.

    2014-07-01

    The new HERMES spectrograph represents the first foray by AAO into the use of commercial off-the-shelf industrial field bus technology for instrument control, and we regard the final system, with its relatively simple wiring requirements, as a great success. However, both software and hardware teams had to work together to solve a number of problems integrating the chosen CANopen/CAN bus system into our normal observing systems. A Linux system running in an industrial PC chassis ran the HERMES control software, using a PCI CAN bus interface connected to a number of distributed CANopen/CAN bus I/O devices and servo amplifiers. In the main, the servo amplifiers performed impressively, although some experimentation with homing algorithms was required, and we hit a significant hurdle when we discovered that we needed to disable some of the encoders used during observations; we learned a lot about how servo amplifiers respond when their encoders are turned off, and about how encoders react to losing power. The software was based around a commercial CANopen library from Copley Controls. Early worries about how this heavily multithreaded library would work with our standard data acquisition system led to the development of a very low-level CANopen software simulator to verify the design. This also enabled the software group to develop and test almost all the control software well in advance of the construction of the hardware. In the end, the instrument went from initial installation at the telescope to successful commissioning remarkably smoothly.

  17. Low-inductance bus lines

    Science.gov (United States)

    Kernick, A.

    1977-01-01

    Laminated bus strips and bifilar litz cable connectors for high-power rectifiers, thrisistors, and transistors provide low inductance and eliminate electromagnetic interference in high-power circuits. These techniques offer significant cost advantages because of ease of assembly and consistent high quality of product. Effectiveness makes general usage in static power conversion likely.

  18. Pybus -- A Python Software Bus

    Energy Technology Data Exchange (ETDEWEB)

    Lavrijsen, Wim T.L.P.

    2004-10-14

    A software bus, just like its hardware equivalent, allows for the discovery, installation, configuration, loading, unloading, and run-time replacement of software components, as well as channeling of inter-component communication. Python, a popular open-source programming language, encourages a modular design on software written in it, but it offers little or no component functionality. However, the language and its interpreter provide sufficient hooks to implement a thin, integral layer of component support. This functionality can be presented to the developer in the form of a module, making it very easy to use. This paper describes a Pythonmodule, PyBus, with which the concept of a ''software bus'' can be realized in Python. It demonstrates, within the context of the ATLAS software framework Athena, how PyBus can be used for the installation and (run-time) configuration of software, not necessarily Python modules, from a Python application in a way that is transparent to the end-user.

  19. Pybus - A Python Software Bus

    International Nuclear Information System (INIS)

    A software bus, just like its hardware equivalent, allows for the discovery, installation, configuration, loading, unloading, and run-time replacement of software components, as well as channeling of inter-component communication. Python, a popular open-source programming language, encourages a modular design on software written in it, but it offers little or no component functionality. However, the language and its interpreter provide sufficient hooks to implement a thin, integral layer of component support. This functionality can be presented to the developer in the form of a module, making it very easy to use. This paper describes a Pythonmodule, PyBus, with which the concept of a ''software bus'' can be realized in Python. It demonstrates, within the context of the ATLAS software framework Athena, how PyBus can be used for the installation and (run-time) configuration of software, not necessarily Python modules, from a Python application in a way that is transparent to the end-user

  20. Development and Implementation of a Battery-Electric Light-Duty Class 2a Truck including Hybrid Energy Storage

    Science.gov (United States)

    Kollmeyer, Phillip J.

    This dissertation addresses two major related research topics: 1) the design, fabrication, modeling, and experimental testing of a battery-electric light-duty Class 2a truck; and 2) the design and evaluation of a hybrid energy storage system (HESS) for this and other vehicles. The work begins with the determination of the truck's peak power and wheel torque requirements (135kW/4900Nm). An electric traction system is then designed that consists of an interior permanent magnet synchronous machine, two-speed gearbox, three-phase motor drive, and LiFePO4 battery pack. The battery pack capacity is selected to achieve a driving range similar to the 2011 Nissan Leaf electric vehicle (73 miles). Next, the demonstrator electric traction system is built and installed in the vehicle, a Ford F150 pickup truck, and an extensive set of sensors and data acquisition equipment is installed. Detailed loss models of the battery pack, electric traction machine, and motor drive are developed and experimentally verified using the driving data. Many aspects of the truck's performance are investigated, including efficiency differences between the two-gear configuration and the optimal gear selection. The remainder focuses on the application of battery/ultracapacitor hybrid energy storage systems (HESS) to electric vehicles. First, the electric truck is modeled with the addition of an ultracapacitor pack and a dc/dc converter. Rule-based and optimal battery/ultracapacitor power-split control algorithms are then developed, and the performance improvements achieved for both algorithms are evaluated for operation at 25°C. The HESS modeling is then extended to low temperatures, where battery resistance increases substantially. To verify the accuracy of the model-predicted results, a scaled hybrid energy storage system is built and the system is tested for several drive cycles and for two temperatures. The HESS performance is then modeled for three variants of the vehicle design, including the

  1. Study on Ultracapacitors Parameter Design and Control Strategy of Electric Bus

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Based on the analysis of ultracapacitors efficiency and vehicle driving character, three conditions restricting the ultracapacitors charge/discharge time are derived. The study focuses on ultracapacitors specific design rules decided by charge/discharge time and how to integrate with battery packs and converter through ultracapacitors' voltage and current double regulators. Through BFC6100-EV electric bus test, it is shown that the proposed method and control strategy are feasible and the system can effectively improve the bus dynamic performance and ability to receive braking energy effectively.

  2. Transformerless dc-Isolated Converter

    Science.gov (United States)

    Rippel, Wally E.

    1987-01-01

    Efficient voltage converter employs capacitive instead of transformer coupling to provide dc isolation. Offers buck/boost operation, minimal filtering, and low parts count, with possible application in photovoltaic power inverters, power supplies and battery charges. In photovoltaic inverter circuit with transformerless converter, Q2, Q3, Q4, and Q5 form line-commutated inverter. Switching losses and stresses nil because switching performed when current is zero.

  3. Button batteries

    Science.gov (United States)

    Swallowing batteries ... These devices use button batteries: Calculators Cameras Hearing aids Penlights Watches ... If a person puts the battery up their nose and breathes it further in, ... problems Cough Pneumonia (if the battery goes unnoticed) ...

  4. Analysis of robustness of urban bus network

    Science.gov (United States)

    Tao, Ren; Yi-Fan, Wang; Miao-Miao, Liu; Yan-Jie, Xu

    2016-02-01

    In this paper, the invulnerability and cascade failures are discussed for the urban bus network. Firstly, three static models(bus stop network, bus transfer network, and bus line network) are used to analyse the structure and invulnerability of urban bus network in order to understand the features of bus network comprehensively. Secondly, a new way is proposed to study the invulnerability of urban bus network by modelling two layered networks, i.e., the bus stop-line network and the bus line-transfer network and then the interactions between different models are analysed. Finally, by modelling a new layered network which can reflect the dynamic passenger flows, the cascade failures are discussed. Then a new load redistribution method is proposed to study the robustness of dynamic traffic. In this paper, the bus network of Shenyang City which is one of the biggest cities in China, is taken as a simulation example. In addition, some suggestions are given to improve the urban bus network and provide emergency strategies when traffic congestion occurs according to the numerical simulation results. Project supported by the National Natural Science Foundation of China (Grant Nos. 61473073, 61374178, 61104074, and 61203329), the Fundamental Research Funds for the Central Universities (Grant Nos. N130417006, L1517004), and the Program for Liaoning Excellent Talents in University (Grant No. LJQ2014028).

  5. Electrical system architecture having high voltage bus

    Science.gov (United States)

    Hoff, Brian Douglas; Akasam, Sivaprasad

    2011-03-22

    An electrical system architecture is disclosed. The architecture has a power source configured to generate a first power, and a first bus configured to receive the first power from the power source. The architecture also has a converter configured to receive the first power from the first bus and convert the first power to a second power, wherein a voltage of the second power is greater than a voltage of the first power, and a second bus configured to receive the second power from the converter. The architecture further has a power storage device configured to receive the second power from the second bus and deliver the second power to the second bus, a propulsion motor configured to receive the second power from the second bus, and an accessory motor configured to receive the second power from the second bus.

  6. A Rule-Based Energy Management Strategy for a Plug-in Hybrid School Bus Based on a Controller Area Network Bus

    OpenAIRE

    Jiankun Peng; Hao Fan; Hongwen He; Deng Pan

    2015-01-01

    This paper presents a rule-based energy management strategy for a plug-in hybrid school bus (PHSB). In order to verify the effectiveness and rationality of the proposed energy management strategy, the powertrain and control models were built with MATLAB/Simulink. The PHSB powertrain model includes an engine model, ISG (integrated started and generator) model, drive motor model, power battery packs model, driver model, and vehicle longitudinal dynamics model. To evaluate the controller area ne...

  7. A Rule-Based Energy Management Strategy for a Plug-in Hybrid School Bus Based on a Controller Area Network Bus

    Directory of Open Access Journals (Sweden)

    Jiankun Peng

    2015-06-01

    Full Text Available This paper presents a rule-based energy management strategy for a plug-in hybrid school bus (PHSB. In order to verify the effectiveness and rationality of the proposed energy management strategy, the powertrain and control models were built with MATLAB/Simulink. The PHSB powertrain model includes an engine model, ISG (integrated started and generator model, drive motor model, power battery packs model, driver model, and vehicle longitudinal dynamics model. To evaluate the controller area network (CAN bus performance features such as the bus load, signal hysteresis, and to verify the reliability and real-time performance of the CAN bus multi-node control method, a co-simulation platform was built with CANoe and MATLAB/Simulink. The co-simulation results show that the control strategy can meet the requirements of the PHSB’s dynamic performance. Meanwhile, the charge-depleting mode (CD and charge-sustaining mode (CS can switch between each other and maintain a state-of-charge (SoC of around 30%, indicating that the energy management strategy effectively extends the working period of the CD mode and improves the fuel economy further. The energy consumption per 100 km includes 13.7 L diesel and 10.5 kW·h electricity with an initial SoC of 75%. The CANoe simulation results show that the bus communication performs well without error frames.

  8. Realization and optimization of bus bar current transducers based on Hall effect sensors

    Science.gov (United States)

    Blagojević, Marjan; Jovanović, Uglješa; Jovanović, Igor; Mančić, Dragan; Popović, Radivoje S.

    2016-06-01

    In this paper the realization and optimization of two coreless open-loop bus bar current transducers based on a Hall effect sensor are presented. Two types of bus bar are evaluated: flat rectangular and rectangular with a restrictive region in the middle. Both realized transducers are capable of measuring AC and DC currents up to 300 A and 10 kHz frequency with nonlinearity less than 0.3% in the entire range. Several methods for resolving issues with the skin effect and stray magnetic fields are presented along with the experimental test results. Some of the presented methods are novel and have never been evaluated.

  9. PWM DC/DC Converter

    OpenAIRE

    Chen, Juan

    2008-01-01

    This report is the result of a Master Thesis work done at Seaward Electronics Inc. in Beijing, China from June to December in 2007. The main goal for this thesis is to verify and improve the performance of Honey-PWM DC-DC converter, which has been fabricated by a standard 0.6um CMOS processes. The project was started with studying of Buck converter structure. After the understanding of the converter structure, the project goes in to the analyses phase for each sub-cells, including the theory,...

  10. Solar Battery Charger in CMOS 0.25 um Technology

    OpenAIRE

    Tao Wang; Chang-Ching Huang; Tian-Jen Wang

    2014-01-01

    A solar cell powered Li-ion battery charger in CMOS 0.25um is proposed. The solar battery charger consists of a DC/DC boost converter and a battery charger. The voltage generated by a solar cell is up converted from 0.65V to 1.8V, which is used as the VDD of the battery charger.  In this way, the solar battery charger automatically converts solar energy to electricity and stores it directly to a Li-ion rechargeable battery. In this system, a super capacitor is needed as a charge buffer betwee...

  11. Hierarchical Control of Parallel AC-DC Converter Interfaces for Hybrid Microgrids

    DEFF Research Database (Denmark)

    Lu, Xiaonan; Guerrero, Josep M.; Sun, Kai;

    2014-01-01

    In this paper, a hierarchical control system for parallel power electronics interfaces between ac bus and dc bus in a hybrid microgrid is presented. Both standalone and grid-connected operation modes in the dc side of the microgrid are analyzed. Concretely, a three-level hierarchical control system...... the three control levels is developed in order to adjust the main control parameters and study the system stability. Experimental results of a 2×2.2 kW parallel ac-dc converter system have shown satisfactory realization of the designed system....

  12. BUS 620 ASHFORD Course Tutorial/TutorialRank

    OpenAIRE

    atwater

    2015-01-01

    For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 4 Times, Rating: A   ASHFORD BUS 620 Week 1 DQ 1 What is Marketing   ASHFORD BUS 620 Week 1 DQ 2 Marketing Strategies   ASHFORD BUS 620 Week 1 Assignment Tesco Case   ASHFORD BUS 620 Week 2 DQ 1 Buyer Behavior   ASHFORD BUS 620 Week 2 DQ 2 Customer Needs   ASHFORD BUS 620 Week 2 Industry Forecasting   ASHFORD BUS 620 Week 3...

  13. BUS 660 ASHFORD Course Tutorial/TutorialRank

    OpenAIRE

    john

    2015-01-01

    For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 4 Times, Rating: A+   BUS 660 Week 1 Assignment Developing Leaders at UPS  BUS 660 Week 2 Assignment Leadership Style  BUS 660 Week 3 Assignment Leadership Traits  BUS 660 Week 4 Assignment Leadership Skills  BUS 660 Week 5 Assignment Big Changes for a Small Hospital  BUS 660 Week 6 Assignment Research Paper BUS 660 Week 1 DQ 1Leadership Defined BU...

  14. Modified Multiport Dc-Dc Converter Topology For Smart Grid

    Directory of Open Access Journals (Sweden)

    Dhamodharan Shanmugam

    2013-10-01

    Full Text Available The development of a Solid State Transformer (SST that incorporates a DC-DC multiport converter to integrate both photovoltaic (PV power generation and battery energy storage is presented in this dissertation. The DC-DC stage is based on a quad active-bridge (QAB converter which not only provides isolation for the load, but also for the PV and storage. The AC-DC stage is implemented with a pulse-widthmodulated (PWM single phase rectifier. A unified gyrator-based average model is developed for a general multi-active-bridge (MAB converter controlled through phase-shift modulation (PSM. Expressions to determine the power rating of the MAB ports are also derived. The developed gyrator-based average model is applied to the QAB converter for faster simulations of the proposed SST during the control design process as well for deriving the state-space representation of the plant. Both linear quadratic regulator (LQR and singleinput-single-output (SISO types of controllers are designed for the DC-DC stage. A novel technique that complements the SISO controller by taking into account the cross coupling characteristics of the QAB converter is also presented herein. Cascaded SISO controllers are designed for the AC-DC stage. The QAB demanded power is calculated at the QAB controls and then fed into the rectifier controls in order to minimize the effect of the interaction between the two SST stages. The dynamic performance of the designed control loops based on the proposed control strategies are verified through extensive simulation of the SST average and switching models.

  15. Design of a New AC–DC Single-Stage Full-Bridge PWM Converter with Two Controllers

    Directory of Open Access Journals (Sweden)

    R. Ramesh,

    2014-03-01

    Full Text Available Single phase power factor correction ac-dc converters are widely used in industry for ac-dc power conversion from single phase ac mains to an required output dc voltage. In case of high power application these types of converter use an ac-dc boost converter followed by dc-dc converter. These converters has the features of excellent input power factor, continuous input and output currents, and intermediate dc bus voltage and reduce the number of semiconductor devices for such cost-effective applications.

  16. PinBus Interface Design

    Energy Technology Data Exchange (ETDEWEB)

    Hammerstrom, Donald J.; Adgerson, Jewel D.; Sastry, Chellury; Pratt, Richard M.; Pratt, Robert G.

    2009-12-30

    On behalf of the U.S. Department of Energy, PNNL has explored and expanded upon a simple control interface that might have merit for the inexpensive communication of smart grid operational objectives (demand response, for example) to small electric end-use devices and appliances. The approach relies on bi-directional communication via the electrical voltage states of from one to eight shared interconnection pins. The name PinBus has been suggested and adopted for the proposed interface protocol. The protocol is defined through the presentation of state diagrams and the pins’ functional definitions. Both simulations and laboratory demonstrations are being conducted to demonstrate the elegance and power of the suggested approach. PinBus supports a very high degree of interoperability across its interfaces, allowing innumerable pairings of devices and communication protocols and supporting the practice of practically any smart grid use case.

  17. Lead-acid battery

    Science.gov (United States)

    Edwards, Dean B. (Inventor); Rippel, Wally E. (Inventor)

    1986-01-01

    A sealed, low maintenance battery (10, 100) is formed of a casing (14, 102) having a sealed lid (12, 104) enclosing cell compartments (22, 110) formed by walls (24, 132). The cells comprise a stack (26) of horizontally disposed negative active plates (30) and positive active plates (28) interspersed with porous, resilient separator sheets (30). Each plate has a set of evenly spaced tigs (40, 41) disposed on one side thereof; like polarity tigs being disposed on one side and opposite polarity tigs on the other. Columns of tigs are electrically and mechanically joined by vertical bus bars (46). The bus bars contain outwardly projecting arms (56) of opposite polarity which are electrically joined at each partition wall (24) to electrically connect the cells in series. The stack is compressed by biasing means such as resilient pad (58) attached to the lid or by joining the tigs (52) to the post (48) at a distance less than the thickness of the mat (124). The end bus bars (46) are joined to straps (60, 62) which connect to the terminals (16, 18). The negative plates contain more capacity than the positive plates and the starved electrolyte imbibed in the separator sheets permits pressurized operation during which oxygen diffuses through the separator sheet to the negative plate where it recombines. Excess pressure is relieved through the vent and pressure relief valve (20).

  18. New TPG bus route 28

    CERN Multimedia

    2003-01-01

    Geneva's Public Transport services (TPG) have recently inaugurated a new bus line 28, connecting the La Tour Hospital in Meyrin to the international organisations in Geneva, via the airport. All signs associated with this route will be yellow in colour. Timetables and route details can be found at http://www.tpg.ch. Relations with the Host States Service http://www.cern.ch/relations/ Tel. 72848

  19. Bus Routes, Marta Bus Routes located in Transportation database, Published in unknown, City of Roswell, GA.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Bus Routes dataset as of unknown. It is described as 'Marta Bus Routes located in Transportation database'. Data by this publisher are often provided in State...

  20. Isolerad DC/DC-omvandlare

    OpenAIRE

    Andersson, Martin

    2011-01-01

    1 SammanfattningCrossControl är ett företag som bland annat tillverkar integrerade datorlösningar. Datorerna drivs normalt med 18-30 VDC och förbrukar som mest 50W. Datorerna säljs till flertalet olika kunder som monterar dem i allt från skogsmaskiner till tåg. I de olika fordonen varierar spänningen i de befintliga elnäten. Detta skapar behovet av att omvandla spänningen till en nivå som datorerna klarar av. En sådan apparat kallas DC/DC-omvandlare. Spänningsomvandling kan utföras genom linj...

  1. State of health detection for Lithium ion batteries in photovoltaic system

    International Nuclear Information System (INIS)

    Highlights: ► DC resistances of batteries. ► Fuzzy logic inference. ► SOH detection for battery. - Abstract: In many photovoltaic systems, rechargeable batteries are required to even out irregularities in solar irradiation. However, the health conditions of the batteries are crucial for the reliability of the overall system. In this paper, the equivalent DC resistances of Lithium ion battery cells of various health conditions during charging under different temperatures have been collected and the relationships between equivalent DC resistance, health condition and working temperature have been identified. The equivalent DC resistance can easily be obtained during the charging period of a battery by switching off the charging current periodically for a very short duration of time. A simple and effective battery charger with state of health (SOH) detection for Lithium ion battery cell has been developed based on the identified equivalent DC resistance. Experimental results are included to demonstrate the effectiveness of the proposed SOH determination scheme.

  2. YUTONG BUS: Grateful To The Financial Crisis

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Shenyin&Wanguo Securities issued an announcement on Jan 9 rating Yutong Bus(600066)as"buying",on the basis that the bus maker's gross profits went better in the last quarter of 2008 and to be further improved in the first quarter of 2009,with an increased market share. The report drew attention inside the in- dustry when the entire bus segment was suffering a tough time.

  3. High voltage bus and auxiliary heater control system for an electric or hybrid vehicle

    Science.gov (United States)

    Murty, Balarama Vempaty

    2000-01-01

    A control system for an electric or hybrid electric vehicle includes a vehicle system controller and a control circuit having an electric immersion heater. The heater is electrically connected to the vehicle's high voltage bus and is thermally coupled to a coolant loop containing a heater core for the vehicle's climate control system. The system controller responds to cabin heat requests from the climate control system by generating a pulse width modulated signal that is used by the control circuit to operate the heater at a duty cycle appropriate for the amount of cabin heating requested. The control system also uses the heater to dissipate excess energy produced by an auxiliary power unit and to provide electric braking when regenerative braking is not desirable and manual braking is not necessary. The control system further utilizes the heater to provide a safe discharge of a bank of energy storage capacitors following disconnection of the battery or one of the high voltage connectors used to transmit high voltage operating power to the various vehicle systems. The control circuit includes a high voltage clamping circuit that monitors the voltage on the bus and operates the heater to clamp down the bus voltage when it exceeds a pre-selected maximum voltage. The control system can also be used to phase in operation of the heater when the bus voltage exceeds a lower threshold voltage and can be used to phase out the auxiliary power unit charging and regenerative braking when the battery becomes fully charged.

  4. A Lemon Cell Battery for High-Power Applications

    Science.gov (United States)

    Muske, Kenneth R.; Nigh, Christopher W.; Weinstein, Randy D.

    2007-01-01

    The use of lemon cell battery to run an electric DC motor is demonstrated for chemistry students. This demonstration aids the students in understanding principles behind the design and construction of the lemon cell battery and principles governing the electric DC motor and other basic principles.

  5. Fast Charging Battery Buses for the Electrification of Urban Public Transport : A Feasibility Study Focusing on Charging Infrastructure and Energy Storage Requirements

    OpenAIRE

    Matthias Rogge; Sebastian Wollny; Dirk Uwe Sauer

    2015-01-01

    The electrification of public transport bus networks can be carried out utilizing different technological solutions, like trolley, battery or fuel cell buses. The purpose of this paper is to analyze how and to what extent existing bus networks can be electrified with fast charging battery buses. The so called opportunity chargers use mainly the regular dwell time at the stops to charge their batteries. This results in a strong linkage between the vehicle scheduling and the infrastructure plan...

  6. Wishbone Bus Architecture - A Survey and Comparison

    Directory of Open Access Journals (Sweden)

    Mohandeep Sharma

    2012-05-01

    Full Text Available The performance of an on-chip interconnection architecture used for communication between IP cores depends on the efficiency of its bus architecture. Any bus architecture having advantages of faster bus clock speed, extra data transfer cycle, improved bus width and throughput is highly desirable for a low cost, reduced time-to-market and efficient System-on-Chip (SoC. This paper presents a survey of WISHBONE bus architecture and its comparison with three other on-chip bus architectures viz. Advanced Microcontroller Bus Architecture (AMBA by ARM, CoreConnect by IBM and Avalon by Altera. The WISHBONE Bus Architecture by Silicore Corporation appears to be gaining an upper edge over the other three bus architecture types because of its special performance parameters like the use of flexible arbitration scheme and additional data transfer cycle (Read-Modify-Write cycle. Moreover, its IP Cores are available free for use requiring neither any registration nor any agreement or license.

  7. Electrical characterization of standard and radiation-hardened RCA CDP1856D 4-BIT, CMOS, bus buffer/separator

    Science.gov (United States)

    Stokes, R. L.

    1979-01-01

    Tests performed to determine accuracy and efficiency of bus separators used in microprocessors are presented. Functional, AC parametric, and DC parametric tests were performed in a Tektronix S-3260 automated test system. All the devices passed the functional tests and yielded nominal values in the parametric test.

  8. High Energy Batteries for Hybrid Buses

    Energy Technology Data Exchange (ETDEWEB)

    Bruce Lu

    2010-12-31

    EnerDel batteries have already been employed successfully for electric vehicle (EV) applications. Compared to EV applications, hybrid electric vehicle (HEV) bus applications may be less stressful, but are still quite demanding, especially compared to battery applications for consumer products. This program evaluated EnerDel cell and pack system technologies with three different chemistries using real world HEV-Bus drive cycles recorded in three markets covering cold, hot, and mild climates. Cells were designed, developed, and fabricated using each of the following three chemistries: (1) Lithium nickel manganese cobalt oxide (NMC) - hard carbon (HC); (2) Lithium manganese oxide (LMO) - HC; and (3) LMO - lithium titanium oxide (LTO) cells. For each cell chemistry, battery pack systems integrated with an EnerDel battery management system (BMS) were successfully constructed with the following features: real time current monitoring, cell and pack voltage monitoring, cell and pack temperature monitoring, pack state of charge (SOC) reporting, cell balancing, and over voltage protection. These features are all necessary functions for real-world HEV-Bus applications. Drive cycle test data was collected for each of the three cell chemistries using real world drive profiles under hot, mild, and cold climate conditions representing cities like Houston, Seattle, and Minneapolis, respectively. We successfully tested the battery packs using real-world HEV-Bus drive profiles under these various climate conditions. The NMC-HC and LMO-HC based packs successfully completed the drive cycles, while the LMO-LTO based pack did not finish the preliminary testing for the drive cycles. It was concluded that the LMO-HC chemistry is optimal for the hot or mild climates, while the NMC-HC chemistry is optimal for the cold climate. In summary, the objectives were successfully accomplished at the conclusion of the project. This program provided technical data to DOE and the public for assessing

  9. Diseño estático de un convertidor DC/DC reductor-elevador bidireccional

    Directory of Open Access Journals (Sweden)

    Marcela González Valencia

    2010-06-01

    Full Text Available This paper shows a buck-boost converter static design with 3 switches and cascade connection. The main application of the converter is the battery management on uninterruptible power supplies, cotrolling energy flow and regulating the DC supply voltage for the different battery operation modes as source and sink.

  10. A new bus lane on urban expressway with no-bay bus stop

    Science.gov (United States)

    Tian, Zhao; Jia, Limin

    2016-01-01

    The sharp increase in residents and vehicles causes heavy traffic pressure in many cities. To ease traffic congestion, it has been the common sense that we should develop public transit system. The priority of the bus appears particularly necessary with the rapid development of the public transport system. The bus lane is an important embodiment of the bus priority. Focusing on the problem of the unreasonable dedicated bus lane (DBL) under the lower ratio of buses, this paper proposed a new bus lane with limited physical length. And this bus lane can reduce the lane-changing conflict caused by the buses and cars running on roads without bus lanes. Based on the cellular automata (CA) traffic flow model and the lane-changing behavior of the vehicle including the optional lane-changing and the mandatory lane-changing, a three-lane traffic model with an isolated no-bay bus stop is proposed. The ordinary three-lane traffic without a bus lane and the cases of traffic with a DBL or the proposed bus lane are simulated, and the comparisons in the form of the fundamental diagrams are made among them. It is shown that the no-bay bus stop can act as a bottleneck on the traffic flow because of the mandatory lane-changing behavior. Under a certain ratio of the bus number to the total vehicles number, (1) the traffic with the proposed bus lane has less lane-changing conflict and can provide higher traffic capacity than the ordinary traffic without a bus lane, (2) compared with the DBL, the proposed bus lane is advantageous in easing congestion on the ordinary lanes when the traffic flow is high and can avoid unreasonable allocation of the road resources.

  11. Active control based on an estimator for the bus-pumping cancellation in the half-bridge class-d audio power amplifiers

    OpenAIRE

    Sala Caselles, Vicenç; Romeral Martínez, José Luis

    2011-01-01

    In this paper is presented a new technique to avoid the distortion generated due to mid point voltage variations on DC-Bus of Class-D Half Bridge audio amplifiers. An usual distortion source on Class-D amplifier is the Bus-Pumping effect. Bus-Pumping causes characteristic distortion and introduces attenuation on output gain. Due to this effect the amplifier efficiency decreases. By including distortion factors on the Half-Bridge amplifier model a new Hybrid Active Control (HAC) is implemen...

  12. Fuzzy Control of a Lead Acid Battery Charger

    Directory of Open Access Journals (Sweden)

    A. DAOUD

    2005-03-01

    Full Text Available In this paper, an alternative battery charging control technique based on fuzzy logic for photovoltaic (PV applications is presented. A PV module is connected to a buck type DC/DC power converter and a microcontroller based unit is used to control the lead acid battery charging voltage. The fuzzy control is used due to the simplicity of implementation, robustness and independence from the complex mathematical representation of the battery. The usefulness of this control method is confirmed by experiments.

  13. Usage of a dc-to-dc converter for voltage adaption between energy storage and propulsion system in electric or hybrid vehicles; Einsatz eines DC/DC-Wandlers zur Spannungsanpassung zwischen Antrieb und Energiespeicher in Elektro- und Hybridfahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Schoenen, Timo

    2011-07-01

    Every time a new hybrid or electrical vehicle is developed, different topologies are compared to achieve the best results regarding weight costs and efficiency. The integration of a dc-to-dc converter between the battery stack and the power train is a frequently discussed alternative because the preferred voltage of the inverter and machine are often higher than the voltage of the battery stack. Within this thesis this approach was studied in detail and compared with the conventional concept without using a dc-to-dc converter. Therefore the influence of the dc-link voltage on the components like battery stack, machine, inverter and dc-to-dc converter was investigated. A change of the dc-link voltage leads to changes inside the components which affect weight, surface of the semiconductor devices and efficiency. This correlation could be used to develop a simulation process which optimizes the dc-link voltage regarding the programmed targets. In hybrid and electrical vehicles low weight and minimum costs are important and were defined as the main targets to achieve. The vantages which arise by using a dc-to-dc converter can be opposed to the disadvantages which also occur. The additional degree of freedom caused by the dc-to-dc converter shall be used. To achieve the best results regarding efficiency, the dc-link voltage has to be adapted to the operating point of the machine. First of all the dc-to-dc converter is an additional component with its weight, volume and losses. By the increased dc-link voltage on the drive train side, the size of the semiconductor devices inside the inverter could be reduced. Therefore the number of windings inside the machine has to be adapted accordingly. Also the wiring could be decreased based on the reduced currents. Overall there is still a higher weight and volume caused by the dc-to-dc converter. Also the efficiency map is influenced by the dc-to-dc converter. In the base speed region the dc-to-dc converter leads to a higher

  14. Mastering NServiceBus and persistence

    CERN Document Server

    Helton, Rich

    2014-01-01

    This book is intended for developers, designers, and architects alike who wish to build C# NServiceBus enterprise architectures and learn how ESB persists data and messages to help them attain their goals. No prior knowledge of persistence in NServiceBus is required.

  15. Li-Ion Battery Charging with a Buck-Boost Power Converter for a Solar Powered Battery Management System

    OpenAIRE

    Chien-Wei Ma; Jaw-Kuen Shiau

    2013-01-01

    This paper analyzes and simulates the Li-ion battery charging process for a solar powered battery management system. The battery is charged using a non-inverting synchronous buck-boost DC/DC power converter. The system operates in buck, buck-boost, or boost mode, according to the supply voltage conditions from the solar panels. Rapid changes in atmospheric conditions or sunlight incident angle cause supply voltage variations. This study develops an electrochemical-based equivalent circuit mod...

  16. Effect of DC Link Control Strategies on Multiterminal AC-DC Power Flow

    Directory of Open Access Journals (Sweden)

    Shagufta Khan

    2015-01-01

    Full Text Available For power-flow solution of power systems incorporating multiterminal DC (MTDC network(s, five quantities are required to be solved per converter. On the other hand, only three independent equations comprising two basic converter equations and one DC network equation exist per converter. Thus, for solution, two additional equations are required. These two equations are derived from the control specifications adopted for the DC links. Depending on the application, several combinations of valid control specifications are possible. Each combination of a set of valid control specifications is known as a control strategy. The number of control strategies increases with an increase in the number of the DC terminals or converters. It is observed that the power-flow convergence of integrated AC-MTDC power systems is strongly affected by the control strategy adopted for the DC links. This work investigates the mechanism by which different control strategies affect the power-flow convergence pattern of AC-MTDC power systems. To solve the DC variables in the Newton-Raphson (NR power-flow model, sequential method is considered in this paper. Numerous case studies carried out on a three-terminal DC network incorporated in the IEEE-300 bus test system validate this.

  17. A simple DC-UPS based in forward-forward topology, design and simulation

    OpenAIRE

    Flores Oropeza, Luis Alejandro; García Suárez, Oscar; Román Loera, Alejandro; Esparza González, Mario S.

    2008-01-01

    This paper presents the analysis, design and simulation of a simple DC-UPS converter with integrated back-up and automatic transition. This converter makes automatic transitions between the main AC and the battery when a failure occurs; and it delivers uninterrupted DC power to the load through two independent power sources of commercial input power and battery power. The converter has the following characteristics: automatic transition between the main and the battery, no additional control ...

  18. A Secondary Voltage Control Method for an AC/DC Coupled Transmission System Based on Model Predictive Control

    DEFF Research Database (Denmark)

    Xu, Fengda; Guo, Qinglai; Sun, Hongbin;

    2015-01-01

    to keep the voltage of the pilot bus tracking its set point considering the DC system’s transmission schedule change. The approach is inspired by model predictive control (MPC) to compensate for predictable voltage change affected by DC side transmission power flow and the potential capacitor switching...

  19. Bidirectional converter interface for a battery energy storage test bench

    DEFF Research Database (Denmark)

    Trintis, Ionut; Thomas, Stephan; Blank, Tobias;

    2011-01-01

    This paper presents the bidirectional converter interface for a 6 kV battery energy storage test bench. The power electronic interface consists a two stage converter topology having a low voltage dc-ac grid connected converter and a new dual active bridge dc-dc converter with high transformation...

  20. Bipolar nickel-hydrogen battery development - A program review

    Science.gov (United States)

    Manzo, Michelle; Lenhart, Stephen; Hall, Arnold

    1989-01-01

    An overview of spacecraft power system design trends, focusing on higher power bus voltages and improved energy storage systems, is followed by a discussion of bipolar Ni/H2 battery development efforts. Several 10-cell batteries and one 50-cell battery are described, and performance results are presented. A comparison of individual-pressure-vessel and bipolar Ni/H2 technologies is used to suggest a new direction for bipolar Ni/H2 battery development efforts, toward a large number of passively cooled cells in parallel.

  1. A Multiphase, Modular, Bidirectional, Triple-Voltage DC-DC Converter Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

    2008-01-01

    Electrical power systems in future hybrid and fuel cell vehicles may employ three voltage [14 V, 42 V, and high voltage (HV)] nets. These will be necessary to accommodate existing 14-V loads as well as efficiently handle new heavy loads at the 42-V net and a traction drive on the HV bus. A low-cost DC-DC converter was proposed for connecting the three voltage nets. It minimizes the number of switches and their associated gate driver components by using two half-bridges and a high-frequency transformer. Another salient feature is that the half bridge on the 42-V bus is also utilized to provide the 14-V bus by operating at duty ratios around an atypical value of 1/3. Moreover, it makes use of the parasitic capacitance of the switches and the transformer leakage inductance for soft switching. The use of half bridges makes the topology well suited for interleaved multiphase modular configurations as a means to increase the power level because the capacitor legs can be shared. This paper presents simulation and experimental results on an interleaved two-phase arrangement rated at 4.5 kW. Also discussed are the benefits of operating with an atypical duty ratio on the transformer and a preferred multiphase configuration to minimize capacitor ripple currents.

  2. High speed bus technology development

    Science.gov (United States)

    Modrow, Marlan B.; Hatfield, Donald W.

    1989-09-01

    The development and demonstration of the High Speed Data Bus system, a 50 Million bits per second (Mbps) local data network intended for avionics applications in advanced military aircraft is described. The Advanced System Avionics (ASA)/PAVE PILLAR program provided the avionics architecture concept and basic requirements. Designs for wire and fiber optic media were produced and hardware demonstrations were performed. An efficient, robust token-passing protocol was developed and partially demonstrated. The requirements specifications, the trade-offs made, and the resulting designs for both a coaxial wire media system and a fiber optics design are examined. Also, the development of a message-oriented media access protocol is described, from requirements definition through analysis, simulation and experimentation. Finally, the testing and demonstrations conducted on the breadboard and brassboard hardware is presented.

  3. A Multiport Isolated DC-DC Converter

    OpenAIRE

    Tran, Yan-Kim; Dujic, Drazen

    2016-01-01

    This paper presents a multi-port isolated DC-DC converter for DC applications. A three-port structure is presented, characterized with full bidirectional power flow and simple control. Galvanic isolation is achieved by means of a multi-winding medium frequency transformer which is a part of a resonant LLC converter. To provide controllable power exchange with external DC ports, two out of three ports are equipped with additional bidirectional buck/boost stages. They serve to provide active po...

  4. Multiport Resonant DC-DC Converter

    OpenAIRE

    Tran, Yan-Kim; Dujic, Drazen; Barrade, Philippe

    2015-01-01

    his paper presents a multiport galvanically isolated LLC resonant DC-DC converter suitable for DC applications. A three-port structure is analyzed, with full bidirectional power flow capabilities, simple control and behavior similar to that expected from a DC transformer. Each port is equipped with half-bridge modules accompanied with tuned resonant tank, partly realized with elements of a multi- winding high frequency transformer. With some restrictions that are explained in the paper, each ...

  5. VLSI Hybrid DC-DC Regulator

    OpenAIRE

    Cosp Vilella, Jordi; Martínez García, Herminio

    2015-01-01

    Hybrid DC-DC regulators are structures that combine both a linear voltage regulator and a switching DC-DC converter. The main objective of this hybrid topology is to converge, in a single circuit topology, the best of both alternatives: a small voltage output ripple, which is a common characteristic of linear regulator circuits, and good energy efficiency, as in switching alternatives. While the linear regulator fixes the required output voltage to a fixed value with negligible steady-state r...

  6. Battery Modeling

    OpenAIRE

    Jongerden, M.R.; Haverkort, B.R.

    2008-01-01

    The use of mobile devices is often limited by the capacity of the employed batteries. The battery lifetime determines how long one can use a device. Battery modeling can help to predict, and possibly extend this lifetime. Many different battery models have been developed over the years. However, with these models one can only compute lifetimes for specific discharge profiles, and not for workloads in general. In this paper, we give an overview of the different battery models that are availabl...

  7. Radiation-Tolerant Dual Data Bus

    Science.gov (United States)

    Kinstler, Gary A.

    2007-01-01

    An architecture, and a method of utilizing the architecture, have been proposed to enable error-free operation of a data bus that includes, and is connected to, commercial off-the-shelf (COTS) circuits and components that are inherently susceptible to singleevent upsets [SEUs (bit flips caused by impinging high-energy particles and photons)]. The architecture and method are applicable, more specifically, to data-bus circuitry based on the Institute for Electrical and Electronics Engineers (IEEE) 1394b standard for a high-speed serial bus.

  8. Drivetrain system of an ultracapacitor electric bus

    Institute of Scientific and Technical Information of China (English)

    Kong Zhigu; Zhu Chunbo; Yang Shiyan; Cheng Shukang

    2007-01-01

    This paper proposed a design of the drivetrain system of an electric bus with ultracapacitor (UC) as the only on-board power source. The system includes three main parts, namely, UC bank, motor and the converter, vehicle management unit (VMU). Analyses results in detail on the functional design and experiments on work bench of each part were also presented, which validated the reliability of the system. Furthermore, driving results in field of the bus verified the feasibility of the design of the drivetrain system. The bus has very good dynamic performances and shows a promising applications prospect in the short and medium route buses system.

  9. BUS 1000母线保护的应用%Application of BUS 1000 Bus-Bar Protection

    Institute of Scientific and Technical Information of China (English)

    马晓光; 张贵金; 冷雪玉

    2001-01-01

    发电厂的母线是电厂中的一个重要组成元件,当母线上发生故障时,将使连接在故障母线上的所有元件在修复故障母线期间,或转换到另一组母线上运行以前遭到停电。同时还可能破坏系统稳定,造成严重后果。因此,母线保护装置是正确迅速切除母线故障的重要装置,它的拒动或误动将给电力系统带来严重危害。详细介绍了华能丹东发电厂350 MW发电机组采用的BUS 1000型母线保护的原理,并对其正常运行及区内、外故障、断路器失灵保护、母联断路器过流保护等几个方面作了详细分析。%Bus bar is an important component in e lectric power plant.When bus bar fault occurs,all components connected on the fa ulty bus bar will be in outage until power restores by repairing the faulty bus bar or switching them over to another bus bar.Furthermore,it may cause the destr uction of system stability resulting in serious consequence.Bus bar protection d evice is the very device to quickly remove bus bar faults,and its malfunctioning will bring serious harm to power system. The principle of BUS 1000 bus bar prot ection used for 350 MW unit of dandong power plant is introduced.Its normal oper ation and several aspects,such as in-and out-area faults,out-of-order breake r protection,bus bar breaker over-current protection,are analyzed in detail.

  10. Energy saving dc-dc converter circuit

    International Nuclear Information System (INIS)

    An energy saving dc-dc converter circuit is disclosed having two energy efficient means which operate in tandem, an energy conserving means and a voltage doubling means. These energy efficient means are applied in combination with elements commonly found in dc-dc converter circuits, namely an ac voltage generator, a transformer for stepping up the generated ac voltage, and means for storing the converted dc voltage. The energy conserving means is connected to the dc voltage storage means. It comprises a resettable inhibit circuit which cuts off the provision of dc voltage for conversion for a predetermined interval when the output of the converter exceeds a predetermined level. The voltage doubling means is reponsive to outputs of the inhibit circuit of the energy conserving means and the ac voltage generator. It provides a phase inverted waveform of the generated ac voltage on one of two leads to the ac voltage step-up transformer

  11. Incremental bus service design: combining limited-stop and local bus services

    OpenAIRE

    Chiraphadhanakul, Virot; Barnhart, Cynthia

    2013-01-01

    Long in-vehicle travel times resulting from frequent stops make bus service an unattractive choice for many commuters. Limited-stop bus services however have the advantage of shorter in-vehicle times experienced by passengers. In this work, we seek to modify a given bus service by optimally reassigning some number of bus trips, as opposed to providing additional trips, to operate a limited-stop service. We propose an optimization model to determine a limited-stop service route to be operated ...

  12. BUS 599 STRAYER Course Tutorial/TutorialRank

    OpenAIRE

    alfonos

    2015-01-01

    For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 4 Times, Rating: A+ STRAYER BUS 599 Week 1 Assignment Crafting and Executing Strategy Case JetBlue Airways STRAYER BUS 599 Week 2 Assignment Competitive Forces and SWOT Analysis Case Whole Foods Market STRAYER BUS 599 Week 3 Assignment Foreign Market Entry and Diversification Case Corona Beer STRAYER BUS 599 Week 4 Assignment HRM Issues Diversification Strategies Case Nucor Corporation STRAYER BUS 5...

  13. The high speed bus technology development program

    Science.gov (United States)

    Ludvigson, M. T.; Modrow, M. B.; Goldman, P. C.

    The current development status of a high-speed data bus to link MIL-STD-1750A computers in avionics applications is reviewed and illustrated with diagrams and photographs. The bus requirements include data rate 50 Mb/s, a linear token-passing scheme permitting both electronic and fiber-optic implementation, up to 64-terminal capacity, maximum terminal separation 300 ft, latency control via token-rotation-timer priority, self-test and bus-loop test capability, and automatic clock synchronization. The design concept and performance of a breadboard wire bus tested in July 1986 are discussed in detail, with particular attention to the redundancy manager, the output controller, the input controller, the ringmaster topology manager, and typical initial-placement problems.

  14. Distributed Secondary Control for DC Microgrid Applications with Enhanced Current Sharing Accuracy

    DEFF Research Database (Denmark)

    Lu, Xiaonan; Guerrero, Josep M.; Sun, Kai

    2013-01-01

    With the consideration of line resistances in a dc microgrid, the current sharing accuracy is lowered down, since the dc output voltage cannot be exactly the same for different interfacing converters. Meanwhile, the dc bus voltage deviation is involved by using droop control. In this paper......, a distributed secondary control method is proposed. Droop control is employed as the primary control method for load current sharing. Meanwhile, the dc output voltage and current in each module is transferred to the others by the low bandwidth communication (LBC) network. Average voltage and current controllers...

  15. Systems evaluation of thermal bus concepts

    Science.gov (United States)

    Stalmach, D. D.

    1982-01-01

    Thermal bus concepts, to provide a centralized thermal utility for large, multihundred kilowatt space platforms, were studied and the results are summarized. Concepts were generated, defined, and screened for inclusion in system level thermal bus trades. Parametric trade studies were conducted in order to define the operational envelope, performance, and physical characteristics of each. Two concepts were selected as offering the most promise for thermal bus development. All of four concepts involved two phase flow in order to meet the required isothermal nature of the thermal bus. Two of the concepts employ a mechanical means to circulate the working fluid, a liquid pump in one case and a vapor compressor in another. Another concept utilizes direct osmosis as the driving force of the thermal bus. The fourth concept was a high capacity monogroove heat pipe. After preliminary sizing and screening, three of these concepts were selected to carry into the trade studies. The monogroove heat pipe concept was deemed unsuitable for further consideration because of its heat transport limitations. One additional concept utilizing capillary forces to drive the working fluid was added. Parametric system level trade studies were performed. Sizing and weight calculations were performed for thermal bus sizes ranging from 5 to 350 kW and operating temperatures in the range of 4 to 120 C. System level considerations such as heat rejection and electrical power penalties and interface temperature losses were included in the weight calculations.

  16. Paintable Battery

    OpenAIRE

    Singh, Neelam; Galande, Charudatta; Miranda, Andrea; Mathkar, Akshay; Gao, Wei; Reddy, Arava Leela Mohana; Vlad, Alexandru; Ajayan, Pulickel M.

    2012-01-01

    If the components of a battery, including electrodes, separator, electrolyte and the current collectors can be designed as paints and applied sequentially to build a complete battery, on any arbitrary surface, it would have significant impact on the design, implementation and integration of energy storage devices. Here, we establish a paradigm change in battery assembly by fabricating rechargeable Li-ion batteries solely by multi-step spray painting of its components on a variety of materials...

  17. CMOS Integrated Capacitive DC-DC Converters

    CERN Document Server

    Van Breussegem, Tom

    2013-01-01

    This book provides a detailed analysis of all aspects of capacitive DC-DC converter design: topology selection, control loop design and noise mitigation. Readers will benefit from the authors’ systematic overview that starts from the ground up, in-depth circuit analysis and a thorough review of recently proposed techniques and design methodologies.  Not only design techniques are discussed, but also implementation in CMOS is shown, by pinpointing the technological opportunities of CMOS and demonstrating the implementation based on four state-of-the-art prototypes.  Provides a detailed analysis of all aspects of capacitive DC-DC converter design;  Analyzes the potential of this type of DC-DC converter and introduces a number of techniques to unleash their full potential; Combines system theory with practical implementation techniques; Includes unique analysis of CMOS technology for this application; Provides in-depth analysis of four fabricated prototypes.

  18. Simulation of a DC to DC power conversion module for the all-electric ship

    OpenAIRE

    Gray, Weston L.; Kirtley, James L.; Chalfant, Julie; Chryssostomidis, Chryssostomos

    2011-01-01

    The design of electric ships requires a tool to evaluate the relative merits of different electrical power distribution configurations; the MIT end-to-end simulator [1] is just such a tool. This paper models one module to be used in conjunction with the end-to-end simulator: a power converter that converts MVDC bus voltage to 1kV DC. First, the power converter was designed to use commercially available technology. This design resulted in a low-frequency, 2 kHz, 200 kW power converter commonly...

  19. Research on Control Strategy of Offshore Wind Farm Based on DC Grid%基于DC-GRID的海上风电场控制策略研究

    Institute of Scientific and Technical Information of China (English)

    袁帅; 王平; 葛宝明

    2012-01-01

    The control strategy of offshore wind farm based on dc-grid was presented, including five VSWT-PMSGs, an offshore full bridge DC-DC converter and an onshore VSC inverter. Each PMSG was connected to the DC-bus. The voltage of DD-bus was stepped up by a Full Bridge DC-DC converter at the offshore HVDC station and then was inverted by the onshore VSC inverter to suit AC grid voltage. The effectiveness of the control strategy was verified by simulation analyses using Matlab/ Simulink.%提出了基于直流传输的海上风电场系统的控制策略,同时建立了基于DC-GRID的海上风电场系统模型。系统由永磁同步风机机组、离岸全桥直直变换器、岸端逆变器组成。各个永磁同步风电机组分别并联在高压大功率全桥DC-DC上,由升压后经过直流传输到岸端VSC之后,经逆变到适合交流电网传输的电压后并网。控制策略以及系统模型由MATLAB/SIMULINK仿真验证。

  20. Dynamic Bus Travel Time Prediction Models on Road with Multiple Bus Routes.

    Science.gov (United States)

    Bai, Cong; Peng, Zhong-Ren; Lu, Qing-Chang; Sun, Jian

    2015-01-01

    Accurate and real-time travel time information for buses can help passengers better plan their trips and minimize waiting times. A dynamic travel time prediction model for buses addressing the cases on road with multiple bus routes is proposed in this paper, based on support vector machines (SVMs) and Kalman filtering-based algorithm. In the proposed model, the well-trained SVM model predicts the baseline bus travel times from the historical bus trip data; the Kalman filtering-based dynamic algorithm can adjust bus travel times with the latest bus operation information and the estimated baseline travel times. The performance of the proposed dynamic model is validated with the real-world data on road with multiple bus routes in Shenzhen, China. The results show that the proposed dynamic model is feasible and applicable for bus travel time prediction and has the best prediction performance among all the five models proposed in the study in terms of prediction accuracy on road with multiple bus routes.

  1. Sexual Harassment on the School Bus: Supporting and Preparing Bus Drivers to Respond Appropriately

    Science.gov (United States)

    Allen, Melissa; Young, Ellie L.; Ashbaker, Betty Y.; Heaton, Emily; Parkinson, Marisa

    2003-01-01

    Sexual harassment is commonplace in schools, particularly among adolescents. Although information on this topic is typically gathered from students and teachers, this study collected information from school bus drivers. Based on feedback from 58 school bus drivers, 39 (67%) reported observing students making sexual comments or jokes. Almost half…

  2. Bullying and Aggression on the School Bus: School Bus Drivers' Observations and Suggestions

    Science.gov (United States)

    deLara, Ellen

    2008-01-01

    Every school day bus drivers are responsible for transporting children safely over many miles, yet they are rarely polled for their opinions or contributions to school safety. School bus drivers are in a unique position to inform the discussion on aggressive behavior during the school day. This exploratory study collected information from school…

  3. Impact of Spanish electricity mix, over the period 2008–2030, on the Life Cycle energy consumption and GHG emissions of Electric, Hybrid Diesel-Electric, Fuel Cell Hybrid and Diesel Bus of the Madrid Transportation System

    International Nuclear Information System (INIS)

    Highlights: • We assess the performance of 4 buses that run on different alternative fuel types and technologies. • The buses assessed are Fuel Cell-Hybrid Bus, Hybrid Diesel-Electric Bus, Battery Electric Bus, and a Diesel Bus. • We examine the environmental impact caused by the Life Cycle of each vehicle technology, fossil fuel and energy carrier. • Life Cycle of Battery Electric Bus shows that it has a big potential of improvement in terms of environmental impact. - Abstract: In spite of the advanced research in automotive technology, and the improvement of fuels, the road transport sector continues to be an environmental concern, since the increase in transport demand is offsetting the effects of these technological improvements. Therefore, this poses the following question: what combination of technology and fuel is more efficient in terms of energy consumption and green house gas (GHG) emissions? To fully address this question it is necessary to carry out a Life Cycle Assessment (LCA). This paper presents a global LCA of 4 buses that run on the following fuel types and technologies: (1) Fuel Cell- Hybrid Bus, (2) Hybrid Diesel-Electric Bus (series configuration), (3) Battery Electric Bus and (4) Combustion Ignition Engine Bus. The impact categories assessed are: primary energy consumption, fossil energy and GHG emissions. Among the principal results, we can conclude that the Global LCA of buses (3) and (1) (which are the more sensitive pathways to the electricity mix variation) have for the 2008–2030 period a room for improvement of 25.62% and 28.16% in terms of efficiency of fossil energy consumption and a potential GHG emission reduction of 28.70% and 30.88% respectively

  4. Dry cell battery poisoning

    Science.gov (United States)

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  5. The Series Connected Buck Boost Regulator Concept for High Efficiency Light Weight DC Voltage Regulation

    Science.gov (United States)

    Birchenough, Arthur G.

    2003-01-01

    Improvements in the efficiency and size of DC-DC converters have resulted from advances in components, primarily semiconductors, and improved topologies. One topology, which has shown very high potential in limited applications, is the Series Connected Boost Unit (SCBU), wherein a small DC-DC converter output is connected in series with the input bus to provide an output voltage equal to or greater than the input voltage. Since the DC-DC converter switches only a fraction of the power throughput, the overall system efficiency is very high. But this technique is limited to applications where the output is always greater than the input. The Series Connected Buck Boost Regulator (SCBBR) concept extends partial power processing technique used in the SCBU to operation when the desired output voltage is higher or lower than the input voltage, and the implementation described can even operate as a conventional buck converter to operate at very low output to input voltage ratios. This paper describes the operation and performance of an SCBBR configured as a bus voltage regulator providing 50 percent voltage regulation range, bus switching, and overload limiting, operating above 98 percent efficiency. The technique does not provide input-output isolation.

  6. The impact of hybrid energy storage on power quality, when high power pulsed DC loads are operated on a microgrid testbed

    Science.gov (United States)

    Kelley, Jay Paul

    . This enables the generator to maintain its operation at levels of high efficiency thereby increasing the power quality of the AC bus. The work discussed here is aimed at evaluating how the use of energy storage impacts the power quality on MicroGrid's AC bus when high rate DC and AC loads are sourced simultaneously. Also HESM has been developed and evaluated as a mean to optimizing both the power and energy density of the energy storage installed.

  7. Experimental analysis on the performance of lithium based batteries for road full electric and hybrid vehicles

    International Nuclear Information System (INIS)

    Highlights: • Performance analysis for lithium storage technologies, such as Li[NiCoMn]O2 and LiFePO4 batteries. • Actual capacity of lithium technologies analyzed almost close to their nominal capacity also for high discharging current. • The charging efficiency for Li[NiCoMn]O2 positively affects the regenerative breaking and fast recharging operations. • The analyzed battery packs follow dynamic power requirements on performed road driving cycles. • Experimental results demonstrate driving range is much higher when battery packs are based on lithium technology. - Abstract: This paper deals with an experimental evaluation regarding the real performance of lithium based energy storage systems for automotive applications. In particular real working operations of different lithium based storage system technologies, such as Li[NiCoMn]O2 and LiFePO4 batteries, are compared in this work from the point of view of their application in supplying full electric and hybrid vehicles, taking as a reference the well-known behavior of lead acid batteries. For this purpose, the experimental tests carried out in laboratory are firstly performed on single storage modules in stationary conditions. In this case the related results are obtained by means of a bidirectional cycle tester based on the IGBT technology, and consent to evaluate, compare and contrast charge/discharge characteristics and efficiency at constant values of current/voltage/power for each storage technology analyzed. Then, lithium battery packs are tested in supplying a 1.8 kW electric power train using a laboratory test bench, based on a 48 V DC bus and specifically configured to simulate working operations of electric vehicles on the road. For this other experimentation the test bench is equipped with an electric brake and acquisition/control system, able to represent in laboratory the real vehicle conditions and road characteristics on predefined driving cycles at different slopes. The obtained

  8. Designing Bus Structure for Digital Controller of Nuclear Power Plant

    International Nuclear Information System (INIS)

    In this paper, the bus structure design for the digital controller of Nuclear Power Plant (NPP) is proposed. The most important portion is the bus in the digital controller. A bus is responsible for transmission data among the various Input/Output (I/O) board, Processor board and Communication board. An existing bus is a parallel bus structure such as the VERSA Module Euro (VME) bus and an extended Static Random Access Memory (SRAM) Controller. Central Processing Unit (CPU) processing speed and communication speed is faster than before, but the parallel bus has a speed limit. Because it is the physically lines shared and the weakness about reflected wave. That is, use of the parallel bus has been the cause of the performance degradation of system. To solve the parallel bus problem, the bus has been developed by serial. The configuration of transceiver logic was simplified by not share the bus that all boards and processor boards was connected to the point-to-point. Serial bus was configured using physically Low Voltage Differential Signaling (LVDS). The speed limit of bus was broken by the LVDS what is consisted of a strong against the reflected-wave of signal, noise and etc. Each channel of bus has a different speed mode and is able to set a required transmission way. Different transmission ways of each channel are able to transmit data to match the required response time of system. The LVDS speed has about basically 1Gbps but the bus was composed with less than 50Mbps considering the environmental characteristics of nuclear. It was shown that the configuration of the serial bus was the performance and the reliability more improving than parallel bus

  9. Statistical Analysis of Bus Networks in India

    CERN Document Server

    Chatterjee, Atanu; Ramadurai, Gitakrishnan

    2015-01-01

    Through the past decade the field of network science has established itself as a common ground for the cross-fertilization of exciting inter-disciplinary studies which has motivated researchers to model almost every physical system as an interacting network consisting of nodes and links. Although public transport networks such as airline and railway networks have been extensively studied, the status of bus networks still remains in obscurity. In developing countries like India, where bus networks play an important role in day-to-day commutation, it is of significant interest to analyze its topological structure and answer some of the basic questions on its evolution, growth, robustness and resiliency. In this paper, we model the bus networks of major Indian cities as graphs in \\textit{L}-space, and evaluate their various statistical properties using concepts from network science. Our analysis reveals a wide spectrum of network topology with the common underlying feature of small-world property. We observe tha...

  10. High speed data bus design validation

    Science.gov (United States)

    Stevens, Rick

    The SAE Linear Implementation Task Group has developed the SAE Linear Token Passing Multiplex Data Bus Standard (AS4074.1) and is currently working on a validation plan. This validation plan will define the test requirements for determining that an implementation of the standard meets the requirements of SAE AS4074.1. Once completed, the test requirements contained in this plan will be executed on bus interface units (BIUs) for validation purposes. In the present work, the author describes the use of a validation model that incorporates many of the capabilities of the validation test plan. This model can also be thought of as a VHDL (VHSIC Hardware Description Language) behavioral representation of the SAE Linear Token Passing Multiplex Data Bus Standard. It is tightly coupled to the standard and provides a model that can be used during the BIU development to validate the design.

  11. Risk factors affecting fatal bus accident severity: Their impact on different types of bus drivers.

    Science.gov (United States)

    Feng, Shumin; Li, Zhenning; Ci, Yusheng; Zhang, Guohui

    2016-01-01

    While the bus is generally considered to be a relatively safe means of transportation, the property losses and casualties caused by bus accidents, especially fatal ones, are far from negligible. The reasons for a driver to incur fatalities are different in each case, and it is essential to discover the underlying risk factors of bus fatality severity for different types of drivers in order to improve bus safety. The current study investigates the underlying risk factors of fatal bus accident severity to different types of drivers in the U.S. by estimating an ordered logistic model. Data for the analysis are retrieved from the Buses Involved in Fatal Accidents (BIFA) database from the USA for the years 2006-2010. Accidents are divided into three levels by counting their equivalent fatalities, and the drivers are classified into three clusters by the K-means cluster analysis. The analysis shows that some risk factors have the same impact on different types of drivers, they are: (a) season; (b) day of week; (c) time period; (d) number of vehicles involved; (e) land use; (f) manner of collision; (g) speed limit; (h) snow or ice surface condition; (i) school bus; (j) bus type and seating capacity; (k) driver's age; (l) driver's gender; (m) risky behaviors; and (n) restraint system. Results also show that some risk factors only have impact on the "young and elder drivers with history of traffic violations", they are: (a) section type; (b) number of lanes per direction; (c) roadway profile; (d) wet road surface; and (e) cyclist-bus accident. Notably, history of traffic violations has different impact on different types of bus drivers. PMID:26513334

  12. Design of E-City Bus Tracking System

    Directory of Open Access Journals (Sweden)

    Shekhar Shinde

    2014-04-01

    Full Text Available E-city bus tracking system will serve as a viable notification system that will effectively assist passengers in making the decision of whether to wait for the bus or not. This system is a standalone system designed to display the real-time location(s of the buses with the use of GSM module technology. The system will consist of an IR transmitter module installed on the buses, receiver boards installed on the bus stops and GSM receiver connected with PC monitoring the whole arrangement. It will also have passenger information system software installed at the bus stops and which will provide user the relevant information regarding all the bus numbers going for his source to destination along with the route details. It will also transmit its bus numbers and route names, with the help of LED transmitter, continuously as soon as the bus comes within the range of the receiver at the bus stop.

  13. The Bus Station Spacing Optimization Based on Game Theory

    Directory of Open Access Journals (Sweden)

    Changjiang Zheng

    2015-01-01

    Full Text Available With the development of city, the problem of traffic is becoming more and more serious. Developing public transportation has become the key to solving this problem in all countries. Based on the existing public transit network, how to improve the bus operation efficiency, and reduce the residents transit trip cost has become a simple and effective way to develop the public transportation. Bus stop spacing is an important factor affecting passengers’ travel time. How to set up bus stop spacing has become the key to reducing passengers’ travel time. According to comprehensive traffic survey, theoretical analysis, and summary of urban public transport characteristics, this paper analyzes the impact of bus stop spacing on passenger in-bus time cost and out-bus time cost and establishes in-bus time and out-bus time model. Finally, the paper gets the balance best station spacing by introducing the game theory.

  14. Secure Bus-Ticketing System using NFC

    Directory of Open Access Journals (Sweden)

    Monalisa Lopes

    2015-04-01

    Full Text Available For making the day to day life more convenient for the passengers travelling in bus some technologies can be used like Near Field Communication (NFC, Radio Frequency Identification (RFID. The proposed system is based on ticketing and identification of passengers in public transport. The system suggest a user friendly automated ticketing system which will automatically deduct the passengers fare according to the distance travelled as well as detect the passengers detail information. The system also helps to calculate the total revenue of a single bus in a day. Another important aspect is reusability, which helps use ticket multiple times as it is rechargeable.

  15. NOC AND BUS ARCHITECTURE: A COMPARISON

    Directory of Open Access Journals (Sweden)

    RAJEEV KAMAL

    2012-04-01

    Full Text Available Network-on-chip designs promise to offer considerable advantages over the traditional bus-based architecture. As continuing scaling of Moore’s law enables ever greater transistor densities, design complexity, power limitations and application convergence networks have started to replace busses in much smaller systems and the enhancement of NoC. This paper summarizes the advantages of the NoC and the limitations of traditional bus based architecture. In this paper we discuss a detailed comparison of area, power, scalability andperformance of traditional busses in comparison with NoC.

  16. An Efficient Segmental Bus-Invert Coding Method for Instruction Memory Data Bus Switching Reduction

    Directory of Open Access Journals (Sweden)

    Gu Ji

    2009-01-01

    Full Text Available Abstract This paper presents a bus coding methodology for the instruction memory data bus switching reduction. Compared to the existing state-of-the-art multiway partial bus-invert (MPBI coding which relies on data bit correlation, our approach is very effective in reducing the switching activity of the instruction data buses, since little bit correlation can be observed in the instruction data. Our experiments demonstrate that the proposed encoding can reduce up to 42% of switching activity, with an average of 30% reduction, while MPBI achieves just 17.6% reduction in switching activity.

  17. Air quality on bus routes in Umea, Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Sandberg, H.; Forsberg, B. [Dept. of Environmental Health and Dept. of Public Health and Clinical Medicine, Umea University SE, Umea (Sweden)

    2000-07-01

    Bus traffic in some local streets with up to 650 buses per day has resulted in complaints about air pollution and suggestions from residents that the bus routes should be changed to other streets. We have studied nitrogen dioxide and benzene concentrations at five exposed sites and at two representative control sites without bus traffic, and found no general differences in air quality. However, the site and temperature adjusted concentrations fell significantly during a strike among bus drivers. (authors)

  18. Framework for Bus Rapid Transit Development and Deployment Planning

    OpenAIRE

    Miller, Mark A.; Yin, Yafeng; Balvanyos, Tunde; Ceder, Avishai

    2004-01-01

    This report presents the results of its investigation into deployment planning for bus rapid transit systems. In this study, we conducted a macro-scale examination of bus rapid transit systems from technical, operational, institutional, and planning perspectives. We then developed the theoretical foundation for a deployment planning framework for bus rapid transit systems that specifically takes into account the unique features of bus rapid transit that differ from other transit alternatives....

  19. DESIGN AND IMPLEMENTATION OF CLOSED LOOP LCL-T RESONANT DC-TO-DC CONVERTER USING LOW COST EMBEDDED CONTROLLER

    Directory of Open Access Journals (Sweden)

    M. Annamalai

    2012-01-01

    Full Text Available The aim of this study is to simulate and implement open loop and closed loop controlled DC-DC converter for stand-alone wind energy system. Wind turbines, however, are not always very efficient in the wind speeds that are most common to a region. Typically, wind energy systems are designed to be highly efficient in high wind speed and have a cut-off wind speed- below which no energy is captured. In remote locations where wind energy is used for battery charging, the energy lost below the cut-off wind speed could be used for trickle charging or maintaining a battery’s fully charged state. Wind turbines are most efficient when they are operated at one specific Tip-Speed to Wind-Speed Ratio (TSR. Therefore, for the efficient capture of wind power, turbine speed should be controlled to follow the ideal TSR, with an optimal operating point, which is different for every wind speed In this system, the DC-DC converter in the DC link with a constant dc voltage to the load, a DC-DC converter will allow the voltage at the output of a diode bridge rectifier to be controlled. In low wind speed conditions, the voltage may be lowered to prevent the dc link from reverse biasing the diode rectifier. Under high wind speed condition, the voltage may be increased, reducing I2R losses. In addition, adjusting the voltage on the dc rectifier will change the generator terminal voltage and thereby provide control over the current flowing out of the generator. The LCL-T resonant inverter system for both open loop and closed loop DC-to-DC converter systems are simulated using MATLAB simulink power system blocks. This converter has advantages like reduced transformer size, reduced filter size and current source characteristics. The simulation studies indicate that LCL-T type for open and closed loop DC-DC converter can be used with stand-alone wind generator. Constant voltage can be maintained at the output of DC-to-DC converter by using a PWM rectifier at the output

  20. A resonant dc-dc power converter assembly

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a resonant DC-DC power converter assembly comprising a first resonant DC-DC power converter and a second resonant DC-DC power converter having identical circuit topologies. A first inductor of the first resonant DC-DC power converter and a second inductor...... of the second resonant DC-DC power converter are configured for magnetically coupling the first and second resonant DC-DC power converters to each other to forcing substantially 180 degrees phase shift, or forcing substantially 0 degree phase shift, between corresponding resonant voltage waveforms of the first...... and second resonant DC-DC power converters. The first and second inductors are corresponding components of the first and second resonant DC-DC power converters....

  1. A Dual-Input DC-DC Converter Using Clean Energy Power Supplies

    OpenAIRE

    Eguchi, Kei

    2010-01-01

    In this chapter, a serial SC DC-DC converter using clean energy power supplies has been proposed. The validity of the circuit design was confirmed by theoretical analyses, SPICE simulations, and experiments. The proposed converter can realize not only long battery runtime but also small hardware-cost and wide input-range. Concretely, in comparison with the conventional parallel converter using 1.5× step-up SC converters, the proposed converter can achieve 20%

  2. Modular Battery Charge Controller

    Science.gov (United States)

    Button, Robert; Gonzalez, Marcelo

    2009-01-01

    A new approach to masterless, distributed, digital-charge control for batteries requiring charge control has been developed and implemented. This approach is required in battery chemistries that need cell-level charge control for safety and is characterized by the use of one controller per cell, resulting in redundant sensors for critical components, such as voltage, temperature, and current. The charge controllers in a given battery interact in a masterless fashion for the purpose of cell balancing, charge control, and state-of-charge estimation. This makes the battery system invariably fault-tolerant. The solution to the single-fault failure, due to the use of a single charge controller (CC), was solved by implementing one CC per cell and linking them via an isolated communication bus [e.g., controller area network (CAN)] in a masterless fashion so that the failure of one or more CCs will not impact the remaining functional CCs. Each micro-controller-based CC digitizes the cell voltage (V(sub cell)), two cell temperatures, and the voltage across the switch (V); the latter variable is used in conjunction with V(sub cell) to estimate the bypass current for a given bypass resistor. Furthermore, CC1 digitizes the battery current (I1) and battery voltage (V(sub batt) and CC5 digitizes a second battery current (I2). As a result, redundant readings are taken for temperature, battery current, and battery voltage through the summation of the individual cell voltages given that each CC knows the voltage of the other cells. For the purpose of cell balancing, each CC periodically and independently transmits its cell voltage and stores the received cell voltage of the other cells in an array. The position in the array depends on the identifier (ID) of the transmitting CC. After eight cell voltage receptions, the array is checked to see if one or more cells did not transmit. If one or more transmissions are missing, the missing cell(s) is (are) eliminated from cell

  3. Bus Stops, This shapefile contains existing bus stops for Charlotte Area Transit System, Published in 2006, Charlotte Area Transit System.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Bus Stops dataset, was produced all or in part from Field Survey/GPS information as of 2006. It is described as 'This shapefile contains existing bus stops for...

  4. Peptic ulcer among urban bus drivers in Denmark

    DEFF Research Database (Denmark)

    Netterstrøm, Bo; Juel, K

    1990-01-01

    As part of a survey on the work environment of bus drivers, 2045 (83%) of 2465 male bus drivers in the three major cities in Denmark in 1978 answered a postal questionnaire on health and working conditions. In order to evaluate the relative occurrence of peptic ulcer among the bus drivers, a follow...

  5. Analysis and Design of Two-stage Isolated Bi-directional DC/DC Converter%一种两级式隔离型双向DC/DC变换器的分析与设计

    Institute of Scientific and Technical Information of China (English)

    张东; 王一军

    2016-01-01

    A two-stage isolated bi-directional DC/DC converter is proposed. The converter is composed of a regulated front-end DC/DC converter and a unregulated back-end LLC resonant converter. When the energy flows from low-voltage DC bus to high-voltage DC bus, the converter is equivalent to Boost converter cascaded full bridge LLC resonant converter with output voltage doubling. When the energy flow is reversed, the converter is equivalent to half bridge LLC resonant converter cascaded Buck converter. The operational theory and key design point are analyzed, and efficiency-oriented optimization method of middle-voltage DC bus is proposed. A prototype of 1kW, 12 V/336 V is build, and the optimum nominal voltage of middle-voltage DC bus is 50 V. The experimental results verify the good performance of the proposed converter.%提出了一种两级式隔离型双向DC/DC变换器,该变换器包含一个闭环的前级DC/DC变换器和一个开环的后级LLC谐振变换器。当能量从低压直流母线传输到高压直流母线时,变换器等效为Boost变换器+全桥倍压LLC谐振变换器;当能量反方向流动时,变换器等效为半桥LLC谐振变换器+Buck变换器。通过分析变换器工作原理与设计要点,提出了以效率为目标的中间直流母线电压优化方法,并研制了1台12 V/336 V、1 kW的样机,其优化后的中间直流母线电压额定值为50 V。样机实验结果验证了所提变换器的良好工作性能。

  6. DC source assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, Jeremy B; Newson, Steve

    2013-02-26

    Embodiments of DC source assemblies of power inverter systems of the type suitable for deployment in a vehicle having an electrically grounded chassis are provided. An embodiment of a DC source assembly comprises a housing, a DC source disposed within the housing, a first terminal, and a second terminal. The DC source also comprises a first capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the first terminal. The DC source assembly further comprises a second capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the second terminal.

  7. Bidirectional Five-Level Power Processing Interface for Low Voltage Battery Energy Storage System

    Science.gov (United States)

    Huang, Jain-Yi; Jou, Hurng-Liahng; Wu, Kuen-Der; Lin, You-Si; Wu, Jinn-Chang

    A bidirectional five-level power processing interface for low voltage battery energy storage system (BESS) is developed in this paper. This BESS consists of a bidirectional five-level DC-AC converter, a bidirectional dual boost/buck DC-DC converter and a battery set. This five-level DC-AC converter includes a bidirectional full-bridge converter and a bidirectional dual buck DC-DC converter. The five-level power processing interface can charge power to the battery set form the utility or discharge the power from the battery set to the utility depending on the demanded operation of user. A hardware prototype is developed to verify the performance of this BESS. Experimental results show the performance of the developed BESS is as expected.

  8. An appraisal of QR code use to deliver bus arrival time information at bus stops in Southampton

    OpenAIRE

    Gammer, Nick

    2011-01-01

    The provision of at-stop bus arrival time information has numerous potential benefits to bus users. With real-time passenger information well established in the UK the challenge is relaying accurate bus arrival times to passengers in a cost effective manner. Display screens are costly to install and maintain, rendering placement at all bus stops economically undesirable. QR codes represent an inexpensive alternative to delivering this information, usually at zero marginal cost to users. Q...

  9. FUEL CELL BUS DEMONSTRATION IN MEXICO CITY

    Science.gov (United States)

    The report discusses the performance of a cull-size, zero-emission, Proton Exchange Membrane (PEM) fuel-cell-powered transit bus in the atmospheric environment of Mexico City. To address the air quality problems caused by vehicle emissions in Mexico City, a seminar on clean vehic...

  10. Inrush-Current Limiter And Bus Isolator

    Science.gov (United States)

    Dolland, Carlisle R.

    1994-01-01

    Electronic circuit protects electrical power bus and source of power against excessive current demands. Circuit intended for use with power-consuming electronic system drawing pulsed currents and including capacitor bank as low-impedance secondary source from which pulsed currents drawn.

  11. Repeater For A Digital-Communication Bus

    Science.gov (United States)

    Torres-Guzman, Esteban; Olson, Stephen; Heaps, Tim

    1993-01-01

    Digital repeater circuit designed to extend range of communication on MIL-STD-1553 bus beyond original maximum allowable length of 300 ft. Circuit provides two-way communication, one way at time, and conforms to specifications of MIL-STD-1553. Crosstalk and instability eliminated.

  12. Virginia School Bus Driver Training: Does Training Program Adequacy Affect school Bus Accident Rates?

    OpenAIRE

    Crews, James O

    1997-01-01

    Analysis of data provided by the Virginia Departments of Motor Vehicles, Transportation, and Education all show school buses as having a significantly higher number of accidents per hundred million miles of travel than other forms of transportation. Such statistics are alarming and formal study of school bus accident factors has been limited. The purposes of this study were to (a) establish the adequacy of the school bus driver training programs of Local Education Agencies(LEAs...

  13. Bus 54 -- Where are you? A school bus intelligent information system

    Energy Technology Data Exchange (ETDEWEB)

    Truett, L.F.; Moore, S.; Tonn, B. [Oak Ridge National Lab., TN (United States); Conley, T. [GTE Wireless, Nashville, TN (United States)

    1998-07-01

    Although major accidents involving school buses are rare (only about 0.3% of all fatal crashes since 1986 are classified as school-bus-related), even minor accidents and breakdowns cause a great deal of parental anxiety. The objective of this research is to design an efficient, cost-effective, accurate, and secure system that will track individual school buses and communicate appropriate information to the school system`s central administration unit, to the school transportation administrator, and to parents of children on the bus. The greatest benefit of the proposed information system is that parents and officials can always know the location and condition (these conditions would vary depending on the needs of a particular school system) of the school buses. In case of an accident or mechanical problem, when emergency crews are needed, they can be dispatched almost immediately with a good understanding of the problem and the exact location of the bus. In addition to being able to track the bus while the child is on board, parents will be able to determine the location of their child`s bus prior to its arrival in the morning in order to prevent the child from needing to wait outside in inclement weather. The information available to parents can also be expanded to include maps of limited routes (e.g., snow routes). Basically, the Bus 54 concept consists of a bus component and a central data processing unit. Each bus will be outfitted with a global positioning satellite (GPS) device, a wireless communication device, and wireless data communication service. The central data processing unit will receive and process information from the buses and provide information access to parents and officials via an Internet link.

  14. Novel DC ring topology and protection system - a comprehensive solution for mega city power grids

    Science.gov (United States)

    Haj-Maharsi, Mohamed Yassine

    2009-07-01

    The development of mega cities leads to increased load concentration and brings additional challenges to managing the electrical grid while keeping power available for critical loads. Techniques using FACTS devices are being applied to alleviate power management difficulties and to confine faults in their originating areas in order to limit the risk of cascading failures in the grid. The addition of many FACTS devices often results in control and protection coordination difficulties, power oscillations between connected networks, subsynchronous resonance problems, and torsional interactions with nearby generator units. The most effective solution is obtained when the individual AC subsystems representing sources and loads are decoupled so a fault in a given subsystem is not propagated to another subsystem. This solution can be achieved by the deployment of a DC system where power sources and loads are connected to the DC bus through voltage source converters. For a mega city, this would be conceived as a DC ring feeding multiple loads and connected to remote and local power sources. Unfortunately, the lack of fast DC circuit breakers has been one of the key issues affecting extensive applications of DC systems with common DC buses; a DC fault would discharge all the capacitors of the DC bus and cause delays in system recovery and possibly a wide system collapse. In this research, I provide a comprehensive solution to mega city power grid problems by proposing a DC system topology that enables grid expansions without affecting existing protection settings or changing existing AC breaker ratings. I also propose the means for protecting the DC system by designing a fast DC breaker and developing a control algorithm capable of isolating DC faults without blocking converter stations or depleting DC bus capacitors. My contribution is three folds: (1) I modeled and simulated Shanghai power grid and performed a study to identify short circuit and voltage stability problems

  15. Bifurcation Analysis of a DC-DC Bidirectional Power Converter Operating with Constant Power Loads

    Science.gov (United States)

    Cristiano, Rony; Pagano, Daniel J.; Benadero, Luis; Ponce, Enrique

    Direct current (DC) microgrids (MGs) are an emergent option to satisfy new demands for power quality and integration of renewable resources in electrical distribution systems. This work addresses the large-signal stability analysis of a DC-DC bidirectional converter (DBC) connected to a storage device in an islanding MG. This converter is responsible for controlling the balance of power (load demand and generation) under constant power loads (CPLs). In order to control the DC bus voltage through a DBC, we propose a robust sliding mode control (SMC) based on a washout filter. Dynamical systems techniques are exploited to assess the quality of this switching control strategy. In this sense, a bifurcation analysis is performed to study the nonlinear stability of a reduced model of this system. The appearance of different bifurcations when load parameters and control gains are changed is studied in detail. In the specific case of Teixeira Singularity (TS) bifurcation, some experimental results are provided, confirming the mathematical predictions. Both a deeper insight in the dynamic behavior of the controlled system and valuable design criteria are obtained.

  16. Design of NPS61000SHEV Extended Range Electric Bus%NPS6100SHEV增程式电动客车设计

    Institute of Scientific and Technical Information of China (English)

    徐本祥

    2011-01-01

    Through the power matching, generator-set matching, battery capacity calculation and control strategy analyzing of NPS6100SHEV extended range electric bus, the author puts forward the overall design requirement and general design method of the extended range electric bus.%通过对NPS6100SHEV增程式电动客车的动力匹配、发电机组匹配、电池容量计算和控制策略分析,提出增程式电动客车的总体设计要求和一般设计方法。

  17. Advanced eGovernment Information Service Bus (eGov-Bus

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available The eGov-Bus project provides citizens and businesses with improved access to virtual public services, which are based on existing national eGovernment Web services and which support cross-border life events. Requirements and specific rules of these life events are considered, and personalization of user preferences is supported. eGov-Bus is based on adaptable process management technologies, allowing for virtual services which are dynamically combined from existing national eGovernment services. In this way, a comprehensive workflow process is set up, allowing for service-level agreements, an audit trail and explanation of the process to the end user. The eGov-Bus process engine operates on top of a virtual repository, providing a high-level semantic view of information retrieved from heterogeneous information sources, such as eGovernment Web services. Further, eGov-Bus relies on a security framework to ensure all high-level security requirements are met. The eGov-Bus architecture is business oriented, it focuses on Service Oriented Architecture (SOA concepts, asynchronously combining Web services and providing a Service Bus.

  18. Regenerative polymeric bus architecture for board-level optical interconnects.

    Science.gov (United States)

    Bamiedakis, N; Hashim, A; Penty, R V; White, I H

    2012-05-21

    A scalable multi-channel optical regenerative bus architecture based on the use of polymer waveguides is presented for the first time. The architecture offers high-speed interconnection between electrical cards allowing regenerative bus extension with multiple segments and therefore connection of an arbitrary number of cards onto the bus. In a proof-of-principle demonstration, a 4-channel 3-card polymeric bus module is designed and fabricated on standard FR4 substrates. Low insertion losses (≤ -15 dB) and low crosstalk values (bus modules using a prototype 3R regenerator.

  19. Heat Transfer in the LHC Main Superconducting Bus Bars

    CERN Document Server

    Granieri, P P; Richter, D

    2011-01-01

    CERN is performing a systematic analysis of the interconnecting bus bars of the Large Hadron Collider (LHC) main magnets. Their thermal, electrical, mechanical and hydraulic performances are addressed. In the frame of these studies, the heat transfer between the main superconducting (SC) bus bars and the surrounding He bath is investigated. It represents a key parameter in the comprehension of the bus bars stability and quench propagation mechanisms, thus crucial for the analysis of the 2008 incident which was triggered by a defective bus bars joint. This paper reports on the experimental tests and relative analysis aiming at describing the thermal behavior of the LHC main bus bars.

  20. 基于磷酸铁锂电池的110kV变电站直流系统中的电池容量选择%Battery Capacity Options of the 110 kV Substation DC System Based on Lithium Iron Phosphate Battery

    Institute of Scientific and Technical Information of China (English)

    王洪; 林雄武; 李丽; 金林; 刘平; 刘轶

    2011-01-01

    Lithium iron phosphate battery is a new kind of lithium ion battery with the ability of reliable operation in rigorous conditions, which is being widely concerned in many industries, especially being promoted in the electric car industry and energy storage industry. But it has not been applied in substation as a backup power. Taking a 110 kV substation as an example, combining with the rules of substation and characteristics of Lithium iron phosphate battery, the capacity calculation of lithium iron phosphate battery in substation power field is detailed introduced.%磷酸铁理电池作为新型锂离子电池,以其能在苛刻的条件下可靠运行的能力,正受到各行业的广泛关注,特别是在电动汽车领域和储能领域,已经开始大力推广。但其作为后备电源,在变电站站用电源领域尚未见到应用。文中以某110kv变电站作为范例,结合变电站的规程和磷酸铁锂电池的特性,详细介绍了在站用电源领域磷酸铁锂电池的容量计算。

  1. DC Power System of Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Zhang Liwei

    2013-11-01

    Full Text Available In recent years, environmental and energy problem has become one of the world's hot spot problems. Today, the road cars not only consume a lot of oil resource, but also cause serious pollution to human survival environment. Therefore, to save energy and protect environment, a green environmental friendly electric car instead of fuel car will be needed for sustainable development of the society. Electric vehicle has no pollution, low noise, high efficiency, diversification, simple structure and convenient maintaining; the development of green cleaning electric vehicle is the trend, and the inevitable choice. The power supply system of electric vehicle can be divided into three parts, the battery charging system, motor drive system and dc load power supply system. This paper mainly studies the dc load power supply system. Main function is to convert the high-voltage of the battery in the electric vehicle into low voltage output, provide the power supply for the low voltage dc load, including the car safety system, windshield wiper system, audio system. On the basis of the analysis of the parameters, this article designs the converter, sets up the principle prototype, analyzes the experimental results and finally makes conclusion. The vehicle power supply is green, environment friendly, high-efficiency, digital and intelligent.    

  2. Particles exposure while sitting at bus stops of hot and humid Singapore

    Science.gov (United States)

    Velasco, Erik; Tan, Sok Huang

    2016-10-01

    Transport microenvironments represent hotspots of personal exposure to airborne toxics, particularly of ultrafine particles. Thus, a large exposure may be experienced during daily commuting trips. Amongst these microenvironments, bus stops are critical because of the commuters' close proximity to fresh fumes rich in particles emitted by passing, idling and accelerating buses and motor vehicles, in general. Standing at a bus stop may represent a period of disproportionately high exposure and it is, therefore, essential to know the number, chemical composition and physical characteristics of such particles for a proper public health assessment and design of mobility strategies. On this account, a set of portable and battery operated sensors were used to evaluate a number of properties of the traffic particles to which thousands of citizens are daily exposed at bus stops of Singapore. In terms of fine particles, the exposure concentration was on average 1.5-3 times higher than the mean concentration at ambient level reported by the local authorities. On average 60% of those particles corresponded to black carbon. An important presence of particle-bound polycyclic aromatics was observed. The particle number concentration and active surface area were effective metrics to quantify ultrafine particles, as expected both showed strong correlations. The number of particles at bus stops was on average 3.5 times higher than at ambient level. The most alarming issue was probably the size of the particles. Assuming spherical particles, a median of 27 nm was estimated based on the active surface area and particle number data. Particles of this size form the nucleation mode, which is related to harmful health effects.

  3. A DC Transformer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — During the period of this project three different possible DC transformer concepts were proposed, theoretically modeled, and then experimentally tested with the...

  4. Power Optimization Distribution and Control Strategies of Multistage Vanadium Redox Flow Battery Energy Storage Systems%多级钒电池储能系统的功率优化分配及控制策略

    Institute of Scientific and Technical Information of China (English)

    李辉; 付博; 杨超; 赵斌; 唐显虎

    2013-01-01

    为了更好利用储能系统平抑大容量风电场功率波动,提出采用多级全钒液流电池(vanadium redox flow battery,VRB)储能的功率优化分配控制策略.首先,在建立VRB等效电路基础上,采用交直流变换器级联多重双向直流变换器作为VRB储能系统接口,分别建立了以稳定直流母线电压为目标的DC/AC变换器矢量控制策略,以电池荷电状态为约束的VRB充放电切换的DC/DC变换器双闭环控制策略.其次,以每级电池组的荷电状态值作为吞吐功率的优选目标,以外部端电压作为电池安全充放电的约束条件,提出多级VRB组的功率优化分配策略.最后,以不同荷电状态(state of charge,SOC)值下的2级VRB储能系统为例,对其在风速波动情况下的风电功率平抑效果以及各个储能单元充放电运行性能进行仿真,并与功率平均分配策略进行对比.结果表明,所提出的多级VRB储能系统功率优化分配和控制策略能很好的平滑风电功率波动,又能减少单台VRB组的充放电次数,并确保电池工作于安全运行区域.%In order to make better use of energy storage system to reduce the fluctuation of active power for large-scale wind farm,this paper proposes the optimization power distribution control strategies of the multistage vanadium redox flow battery (VRB) storage.Firstly,based on the equivalent circuit of a VRB and by using the interface of the DC/AC converter cascade multiple bi-directional DC/DC converter,a vector control strategy of DC/AC converter is presented to keep the stable DC bus voltage,and a double closed loop control strategy of DC/DC converter is established to switch charge-discharge style as a constraint of state of charge (SOC) on a single VRB.Secondly,by taking SOC value of each battery as priority target selection of output power,and by using the limit of external terminal voltage as the constraint conditions for battery safety charging and discharging,an optimization

  5. Radiation Effects on DC-DC Converters

    Science.gov (United States)

    Zhang, De-Xin; AbdulMazid, M. D.; Attia, John O.; Kankam, Mark D. (Technical Monitor)

    2001-01-01

    In this work, several DC-DC converters were designed and built. The converters are Buck Buck-Boost, Cuk, Flyback, and full-bridge zero-voltage switched. The total ionizing dose radiation and single event effects on the converters were investigated. The experimental results for the TID effects tests show that the voltages of the Buck Buck-Boost, Cuk, and Flyback converters increase as total dose increased when using power MOSFET IRF250 as a switching transistor. The change in output voltage with total dose is highest for the Buck converter and the lowest for Flyback converter. The trend of increase in output voltages with total dose in the present work agrees with those of the literature. The trends of the experimental results also agree with those obtained from PSPICE simulation. For the full-bridge zero-voltage switch converter, it was observed that the dc-dc converter with IRF250 power MOSFET did not show a significant change of output voltage with total dose. In addition, for the dc-dc converter with FSF254R4 radiation-hardened power MOSFET, the output voltage did not change significantly with total dose. The experimental results were confirmed by PSPICE simulation that showed that FB-ZVS converter with IRF250 power MOSFET's was not affected with the increase in total ionizing dose. Single Event Effects (SEE) radiation tests were performed on FB-ZVS converters. It was observed that the FB-ZVS converter with the IRF250 power MOSFET, when the device was irradiated with Krypton ion with ion-energy of 150 MeV and LET of 41.3 MeV-square cm/mg, the output voltage increased with the increase in fluence. However, for Krypton with ion-energy of 600 MeV and LET of 33.65 MeV-square cm/mg, and two out of four transistors of the converter were permanently damaged. The dc-dc converter with FSF254R4 radiation hardened power MOSFET's did not show significant change at the output voltage with fluence while being irradiated by Krypton with ion energy of 1.20 GeV and LET of 25

  6. Wide input high step-up isolated DC/DC converter%宽输入高增益隔离升压型DC/DC变换器

    Institute of Scientific and Technical Information of China (English)

    肖文英; 戴日光

    2012-01-01

    隔离升压型DC/DC变换器是一类可以将低压直流母线变换成高压直流母线并实现电气隔离的变换器的统称.该技术在新能源发电领域如燃料电池发电系统以及微逆变器系统中应用广泛,其研究热点是宽输入适应性、高增益和高效率功率变换.LLC谐振变换器很好地符合这些要求.为此,研究了基于全桥LLC谐振变换器的高增益隔离升压型DC/DC变换器,提出了单级式和两级式两种方案,单级式方案为输出稳压LLC谐振变换器,而两级式方案为Boost变换器级联输出不稳压LLC谐振变换器.分别提出了LLC谐振变换器在单级式和两级式方案中的基于最佳励磁电感的谐振腔参数设计方法,并且分别通过样机实验验证了所提出的设计方法的有效性.%The isolated step-up DC/DC converter is a kind of converter that can convert low DC voltage bus into high DC voltage bus and realize electrical isolation. This technology has been widely used in new energy generation, such as fuel cell power system and micro-inverter system. Its research focuses on wide input adaptation, high step-up and high efficiency power conversion. LLC resonant converter perfectly satisfies these requirements. For this reason, high step-up DC/DC converter based on full bridge LLC resonant converter was studied in this paper. Two structures were presented, namely, single-stage structure applying regulated LLC resonant converter and two-stage structure applying Boost converter cascaded unregulated LLC resonant converter. The design method of the resonant tank under different structures based on the optimal magnetizing inductance was proposed. Finally, the prototypes of regulated and unregulated LLC resonant converter were built to verify the verification of the proposed method.

  7. BUS 475 UOP Course Tutorial/ Tutorialrank

    OpenAIRE

    john

    2015-01-01

    For more course tutorials visit www.tutorialrank.com Tutorial Purchased: 6 Times, Rating: A+   BUS 475 Capstone Final Examination Part 1   1.    In the managerial function of __________, managers encourage and motivate workers to work toward organizational goals.   2.    eBay.com is a vast auction site that is similar to a competitive market in some ways but differs from it in others. Which of the following describes...

  8. Exposure Assessment of Diesel Bus Emissions

    Directory of Open Access Journals (Sweden)

    Werner Hofmann

    2006-12-01

    Full Text Available The goal of this study was to measure ultrafine particle concentrations with diameters less than 1 μm emitted by diesel buses and to assess resulting human exposure levels. The study was conducted at the Woolloongabba Busway station in Brisbane, Australia in the winter months of 2002 during which temperature inversions frequently occurred. Most buses that utilize the station are fuelled by diesel, the exhaust of which contains a significant quantity of particle matter. Passengers waiting at the station are exposed to these particles emitted from the buses. During the course of this study, passenger census was conducted, based on video surveillance, yielding person-by-person waiting time data. Furthermore, a bus census revealed accurate information about the total number of diesel versus Compressed Natural Gas (CNG powered buses. Background (outside of the bus station and platform measurements of ultrafine particulate number size distributions were made to determine ambient aerosol concentrations. Particle number exposure concentration ranges from 10 and 40 to 60% of bus related exhaust fumes. This changes dramatically when considering the particle mass exposure concentration, where most passengers are exposed to about 50 to 80% of exhaust fumes. The obtained data can be very significant for comparison with similar work of this type because it is shown in previous studies that exhaust emissions causes cancer in laboratory animals. It was assumed that significant differences between platform and background distributions were due to bus emissions which, combined with passenger waiting times, yielded an estimate of passenger exposure to ultrafine particles from diesel buses. From an exposure point of view, the Busway station analyzed resembles a street canyon. Although the detected exhaust particle concentration at the outbound platform is found to be in the picogram range, exposure increases with the time passengers spend on the platform

  9. Probabilistic safety analysis of DC power supply requirements for nuclear power plants. Technical report

    International Nuclear Information System (INIS)

    A probabilistic safety assessment was performed as part of the Nuclear Regulatory Commission generic safety task A-30, Adequacy of Safety Related DC Power Supplies. Event and fault tree analysis techniques were used to determine the relative contribution of DC power related accident sequences to the total core damage probability due to shutdown cooling failures. It was found that a potentially large DC power contribution could be substantially reduced by augmenting the minimum design and operational requirements. Recommendations included (1) requiring DC power divisional independence, (2) improved test, maintenance, and surveillance, and (3) requiring core cooling capability be maintained following the loss of one DC power bus and a single failure in another system

  10. Fast Charging Battery Buses for the Electrification of Urban Public Transport—A Feasibility Study Focusing on Charging Infrastructure and Energy Storage Requirements

    Directory of Open Access Journals (Sweden)

    Matthias Rogge

    2015-05-01

    Full Text Available The electrification of public transport bus networks can be carried out utilizing different technological solutions, like trolley, battery or fuel cell buses. The purpose of this paper is to analyze how and to what extent existing bus networks can be electrified with fast charging battery buses. The so called opportunity chargers use mainly the regular dwell time at the stops to charge their batteries. This results in a strong linkage between the vehicle scheduling and the infrastructure planning. The analysis is based on real-world data of the bus network in Muenster, a mid-sized city in Germany. The outcomes underline the necessity to focus on entire vehicle schedules instead on individual trips. The tradeoff between required battery capacity and charging power is explained in detail. Furthermore, the impact on the electricity grid is discussed based on the load profiles of a selected charging station and a combined load profile of the entire network.

  11. A Lemon Cell Battery for High-Power Applications

    Science.gov (United States)

    Muske, Kenneth R.; Nigh, Christopher W.; Weinstein, Randy D.

    2007-04-01

    This article discusses the development of a lemon cell battery for high-power applications. The target application is the power source of a dc electric motor for a model car constructed by first-year engineering students as part of their introductory course design project and competition. The battery is composed of a series of lemon juice cells made from UV vis cuvets that use a magnesium anode and copper cathode. Dilution of the lemon juice to reduce the rate of corrosion of the magnesium anode and the addition of table salt to reduce the internal resistance of the cell are examined. Although our specific interest is the use of this lemon cell battery to run an electric dc motor, high-power applications such as radios, portable cassette or CD players, and other battery-powered toys are equally appropriate for demonstration and laboratory purposes using this battery.

  12. Analysis and Controller Design of a Universal Bidirectional DC-DC Converter

    Directory of Open Access Journals (Sweden)

    Kou-Bin Liu

    2016-06-01

    Full Text Available In this paper, first the operating principles of a non-isolated universal bidirectional DC-DC converter are studied and analyzed. The presented power converter is capable of operating in all power transferring directions in buck/boost modes. Zero voltage switching can be achieved for all the power switches through proper modulation strategy design, therefore, the presented converter can achieve high efficiency. To further improve the efficiency, the relationship between the phase-shift angle and the overall system efficiency is analyzed in detail, an adaptive phase-shift (APS control method which determines the phase-shift value between gating signals according to the load level is then proposed. As the modulation strategy is a software-based solution, there is no requirement for additional circuits, therefore, it can be implemented easily and instability and noise susceptibility problems can be reduced. To validate the correctness and the effectiveness of the proposed method, a 300 W prototyping circuit is implemented and tested. A low cost dsPIC33FJ16GS502 digital signal controller is adopted in this paper to realize the power flow control, DC-bus voltage regulation and APS control. According to the experimental results, a 12.2% efficiency improvement at light load and 4.0% efficiency improvement at half load can be achieved.

  13. High Capacity Battery Cell Flight Qualified

    Science.gov (United States)

    McKissock, Barbara I.

    1997-01-01

    The High Capacity Battery Cell project is an effort equally funded by the NASA Lewis Research Center and Hughes Space and Communications Company (a unit of Hughes Aircraft Company) to develop and flight qualify a higher capacity nickel hydrogen battery for continuing use on commercial spacecraft. The larger diameter, individual pressure vessel cell will provide approximately twice the power, while occupying the same volume, as the current state-of-the-art nickel hydrogen cell. These cells are also anticipated to reduce battery cost by 20 percent. The battery is currently booked for use on 26 spacecraft, with the first flight scheduled in 1997. A strong requirement for batteries with higher power levels (6 to 12 kW), long life, and reduced cost was identified in studies of the needs of commercial communications spacecraft. With the design developed in this effort, the higher power level was accommodated without having to modify the rest of the existing spacecraft bus. This design scaled-up the existing state-of-the-art nickel hydrogen battery cell from a 3.5-in., 50-Ahr cell to a 5.5-in., 350-Ahr cell. An improvement in cycle life was also achieved by the use of the 26-percent KOH electrolyte design developed by NASA Lewis. The cell design was completed, and flight batteries were built and flight qualified by Hughes Space and Communications Company with input from NASA Lewis. Two batteries were shipped in September 1996 to undergo life cycle testing under the purview of NASA Lewis.

  14. Study of bus driving parameters on urban route

    OpenAIRE

    Fuad DASHDAMIROV

    2011-01-01

    The article deals with bus traffic time and speed on stage and route in the whole. The factors affecting bus driving parameters are divided into groups. The factors of significant impact are found in each group. The method of consideration of such factors impact on driving parameters in timetable making, is proposed. The extent of impact of selected factors on bus driving time and speed is studied.

  15. The SMART MIL-STD-1553 bus adapter hardware manual

    Science.gov (United States)

    Ton, T. T.

    1981-01-01

    The SMART Multiplexer Interface Adapter, (SMIA) a complete system interface for message structure of the MIL-STD-1553, is described. It provides buffering and storage for transmitted and received data and handles all the necessary handshaking to interface between parallel 8-bit data bus and a MIL-STD serial bit stream. The bus adapter is configured as either a bus controller of a remote terminal interface. It is coupled directly to the multiplex bus, or stub coupled through an additional isolation transformer located at the connection point. Fault isolation resistors provide short circuit protection.

  16. Examination of an Urban City Bus Operating Conditions and Emissions

    OpenAIRE

    Soylu, Seref (Coordinador); Bal, Ayda; Semercioglu, Hulya; Ay, Eyup Fatih

    2010-01-01

    It was observed that real world driving characteristics of the city bus don’t correlate well with that of the ETC, which is the certification cycle for the city bus engines. For this reason it is not realistic to expect emission levels lower than corresponding EURO standards from the city bus during real world driving. City bus NOx emissions in terms of grams per second are increasing with engine load and speed but the total NOx emissions for entire trip are the maximum at the locations whe...

  17. Multi-Gigabit Rate Radiation Hard Bus Project

    Data.gov (United States)

    National Aeronautics and Space Administration — High speed robust very low power radiation hardened bus interconnects are required to accelerate on-board computations, further improve reconfigurability and...

  18. Bus accident severity and passenger injury: evidence from Denmark

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Kaplan, Sigal

    2014-01-01

    light. Occurrence of injury to bus passengers is positively related to (i) the involvement of heavy vehicles, (ii) crossing intersections in yellow or red light, (iii) open areas, (iv) high speed limits, and (v) slippery road surface. Conclusions The findings of the current study provide a comprehensive...... examining occurrence of injury to bus passengers. Results Bus accident severity is positively related to (i) the involvement of vulnerable road users, (ii) high speed limits, (iii) night hours, (iv) elderly drivers of the third party involved, and (v) bus drivers and other drivers crossing in yellow or red...

  19. Status of the IEEE P896 Future Backplane Bus

    International Nuclear Information System (INIS)

    The IEEE P896 Future Backplane Bus project has been influenced by and has influenced FASTBUS and several other contemporary bus designs. This paper summarizes the current status of that project, which is directed toward the needs of modern 32-bit microprocessor systems with multiple processors. Some of the technology developed for P896 will be important for future non-ECL implementations of FASTBUS and other buses. In particular, new bus drivers and receivers should greatly improve the performance and reliability of backplane buses and cable buses. The current status of the P896 serial bus is also summarized

  20. Radiation-Tolerant DC-DC Converters

    Science.gov (United States)

    Skutt, Glenn; Sable, Dan; Leslie, Leonard; Graham, Shawn

    2012-01-01

    A document discusses power converters suitable for space use that meet the DSCC MIL-PRF-38534 Appendix G radiation hardness level P classification. A method for qualifying commercially produced electronic parts for DC-DC converters per the Defense Supply Center Columbus (DSCC) radiation hardened assurance requirements was developed. Development and compliance testing of standard hybrid converters suitable for space use were completed for missions with total dose radiation requirements of up to 30 kRad. This innovation provides the same overall performance as standard hybrid converters, but includes assurance of radiation- tolerant design through components and design compliance testing. This availability of design-certified radiation-tolerant converters can significantly reduce total cost and delivery time for power converters for space applications that fit the appropriate DSCC classification (30 kRad).

  1. KLQ6129GQEV2纯电动客车总体设计%Overall Design of KLQ6129GQEV2 Pure Electric Bus

    Institute of Scientific and Technical Information of China (English)

    代国玉

    2012-01-01

    The author briefly introduces control and management about the KLQ6 the features of vehicle layout design, power batteries arrangement, and it's 129GEV2 pure electric bus.%简要介绍KLQ6129GQEV2纯电动客车的整车布置设计和动力电池布置特点及其控制与管理。

  2. Forback DC-to-DC converter

    Science.gov (United States)

    Lukemire, Alan T.

    1995-05-01

    A pulse-width modulated DC-to-DC power converter including a first inductor, i.e. a transformer or an equivalent fixed inductor equal to the inductance of the secondary winding of the transformer, coupled across a source of DC input voltage via a transistor switch which is rendered alternately conductive (ON) and nonconductive (OFF) in accordance with a signal from a feedback control circuit is described. A first capacitor capacitively couples one side of the first inductor to a second inductor which is connected to a second capacitor which is coupled to the other side of the first inductor. A circuit load shunts the second capacitor. A semiconductor diode is additionally coupled from a common circuit connection between the first capacitor and the second inductor to the other side of the first inductor. A current sense transformer generating a current feedback signal for the switch control circuit is directly coupled in series with the other side of the first inductor so that the first capacitor, the second inductor and the current sense transformer are connected in series through the first inductor. The inductance values of the first and second inductors, moreover, are made identical. Such a converter topology results in a simultaneous voltsecond balance in the first inductance and ampere-second balance in the current sense transformer.

  3. Control strategy for a distributed DC power system with renewable energy

    Energy Technology Data Exchange (ETDEWEB)

    Kurohane, Kyohei; Uehara, Akie; Senjyu, Tomonobu; Yona, Atsushi; Urasaki, Naomitsu [University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami, Okinawa 903-0213 (Japan); Funabashi, Toshihisa [Meidensha Corporation, 36-2 Nihonbashi-Hakozakicho, Chuo-ku, Tokyo 103-8513 (Japan); Kim, Chul-Hwan [Sungkyunkwan University and NPT Center, Suwon City 440-746 (Korea)

    2011-01-15

    This paper deals with a DC-micro-grid with renewable energy. The proposed method is composed of a gearless wind power generation system, a battery, and DC loads in a DC distribution system. The battery helps to avoid the DC over-voltages by absorbing the power of the permanent magnet synchronous generator (PMSG) during line-fault. In addition, the control schemes presented in this paper including the maximum power point tracking (MPPT) control and a pitch angle control for the gearless wind turbine generator. By means of the proposed method, high-reliable power can be supplied to the DC distribution system during the line-fault and stable power supply from the PMSG can be achieved after line-fault clearing. The effectiveness of the proposed method is examined in a MATLAB/Simulink {sup registered} environment. (author)

  4. Multi Port Single Stage Power Electronics Converter and Wind PFC Converter for DC Micro Grid Applications

    Directory of Open Access Journals (Sweden)

    M. Hemachandran

    2014-08-01

    Full Text Available In this study multi port AC/DC-DC single stage power electronics converter proposed for grid power supply. The topology includes reduced number of active element and passive element. Passive element is used to provide to achieve improved voltage gain and to reduce the voltage stress of input side switches. The active-clamp circuits are used to recycle the energy stored in the leakage inductors and to improve the system performances. Here two input port (wind and battery unit and output port connected to dc grid, battery act as charge unit and source. Efficient wind power conversion is achieved by PFC boost dc-dc converter. Controlled and high step up voltage is supplied to multi-port converter from wind source.

  5. Can propulsion and fuel diversity for the bus fleet achieve the win–win strategy of energy conservation and environmental protection?

    International Nuclear Information System (INIS)

    Highlights: • We first report WTW energy and environmental impacts of new-energy buses in China. • Both CNGV and BEV eliminate petroleum use but increase the burden of other fossil fuels. • BEV is the best to reduce WTW NOX and VOC emissions but no benefit for PM2.5 and SO2. • CNGV has PM2.5 emission reductions by 70% greater than DV but no benefit in GHG emissions. • HEV is the only option that can reduce energy use and pollutant emissions at the same time. - Abstract: China is facing serious issues involving energy sufficiency, greenhouse gas (GHG) emissions and air pollution caused partly by the rapid growth of vehicles. In order to relieve those problems, new energy vehicles are introduced into the bus and car market. We adopt life cycle analysis to evaluate the well-to-wheels (WTW) energy consumption, CO2 emissions and pollutant emissions from the traditional diesel bus and new energy buses, including diesel hybrid electric vehicles (HEVs), compressed natural gas vehicles (CNGVs) and battery electric vehicles (BEVs). This study reports the current situation and projects future scenarios for the BEV bus for several regions in China due to significant regional differences in the power generation mix. Compared to the diesel bus, the HEV bus can reduce petroleum, fossil fuel use and CO2 emissions by about 20%, and, at the same time, produce stable reduction benefits for all air pollutants. The CNG bus achieves reductions of WTW primary PM2.5 emissions by 70% over its diesel counterpart and, of course, uses little petroleum; but increases fossil fuel consumption moderately and has no benefit in GHG emissions. The BEV bus can deliver a substantial petroleum consumption advantage and greatly reduce the WTW NOX, VOC and CO emissions; but, if the electricity is generated from burning coal, the BEV bus has no PM2.5 emission benefit compared to the conventional diesel bus. Currently, the BEV bus increases fossil energy use and CO2 emissions in the coal

  6. Oracle Service Bus 11g Development Cookbook

    CERN Document Server

    Schmutz, Guido; van Zoggel, Jan

    2012-01-01

    This cookbook is full of immediately useable recipes showing you how to develop service and message-oriented (integration) applications on the Oracle Service Bus. In addition to its cookbook style, which ensures the solutions are presented in a clear step-by-step manner, the explanations go into great detail, which makes it good learning material for everyone who has experience in OSB and wants to improve. Most of the recipes are designed in such a way that each recipe is presented as a separate, standalone entity and reading of prior recipes is not required. The finished solution of each reci

  7. Bus bar joints stability and protection

    CERN Document Server

    Verweij, A

    2009-01-01

    A defective bus connection between two dipole magnets was the primary cause of the incident in sector 34 on September 19th. I will show how this could have happened, i.e. how a highly resistive joint has caused a thermal runaway and burned (or opened) before the QPS threshold was reached. In the second part of the talk I will present the new detection limits for the QPS upgrade of the RB and RQ circuits, required to avoid similar thermal runaways in the future.

  8. Redesign of Transjakarta Bus Driver's Cabin

    Science.gov (United States)

    Mardi Safitri, Dian; Azmi, Nora; Singh, Gurbinder; Astuti, Pudji

    2016-02-01

    Ergonomic risk at work stations with type Seated Work Control was one of the problems faced by Transjakarta bus driver. Currently “Trisakti” type bus, one type of bus that is used by Transjakarta in corridor 9, serving route Pinang Ranti - Pluit, gained many complaints from drivers. From the results of Nordic Body Map questionnaires given to 30 drivers, it was known that drivers feel pain in the neck, arms, hips, and buttocks. Allegedly this was due to the seat position and the button/panel bus has a considerable distance range (1 meter) to be achieved by drivers. In addition, preliminary results of the questionnaire using Workstation Checklist identified their complaints about uncomfortable cushion, driver's seat backrest, and the exact position of the AC is above the driver head. To reduce the risk level of ergonomics, then did research to design the cabin by using a generic approach to designing products. The risk analysis driver posture before the design was done by using Rapid Upper Limb Assessment (RULA), Rapid Entire Body Assessment (REBA), and Quick Exposure Checklist (QEC), while the calculation of the moment the body is done by using software Mannequin Pro V10.2. Furthermore, the design of generic products was done through the stages: need metric-matrix, house of quality, anthropometric data collection, classification tree concept, concept screening, scoring concept, design and manufacture of products in the form of two-dimensional. While the design after design risk analysis driver posture was done by using RULA, REBA, and calculation of moments body as well as the design visualized using software 3DMax. From the results of analysis before the draft design improvements cabin RULA obtained scores of 6, REBA 9, and the result amounted to 57.38% QEC and moment forces on the back is 247.3 LbF.inch and on the right hip is 72.9 LbF.in. While the results of the proposed improvements cabin design RULA obtained scores of 3, REBA 4, and the moment of force on

  9. Intelligent dc-dc Converter Technology Developed and Tested

    Science.gov (United States)

    Button, Robert M.

    2001-01-01

    The NASA Glenn Research Center and the Cleveland State University have developed a digitally controlled dc-dc converter to research the benefits of flexible, digital control on power electronics and systems. Initial research and testing has shown that conventional dc-dc converters can benefit from improved performance by using digital-signal processors and nonlinear control algorithms.

  10. Arc deflection model and arc direction control for DC arc furnace

    Institute of Scientific and Technical Information of China (English)

    Liping Wei; Huang Zhou; Huade Li; Yuanhang Zhou

    2004-01-01

    Based on the analysis of three-dimensional power conductor for DC arc furnace, the electric arc deflection model was set up and the control system of the arc direction was configured. According to the bus bar distribution at the bottom electrodes cooled by water, the arc direction control principle and its configuration were described. The simulation results show that the control system can restrain the electric arc deflection and control the arc direction.

  11. Transient Analysis of Large Scale PV Systems with Floating DC Section

    OpenAIRE

    George C. Lazaroiu; Federica Foiadelli; Alberto Dolara; Morris Brenna; Sonia Leva

    2012-01-01

    The increasing penetration of renewable sources with power-electronic interfaces in power systems is raising technical problems and the overall efficiency of photovoltaic systems can decrease dramatically. In this context, the optimal layout for the photovoltaic system is required. The most adequate strategy to connect the renewable system to the electrical power grid or to supply the end users must be adopted. The present paper proposes a design layout of a PV plant using a DC bus system to ...

  12. DC Distributed Power Systems - Analysis, Design and Control for a Renewable Energy System

    OpenAIRE

    Karlsson, Per

    2002-01-01

    Renewable energy systems are likely to become wide spread in the future due to environmental demands. As a consequence of the dispersed nature of renewable energy systems, this implies that there will be a distributed generation of electric power. Since most of the distributed electrical energy sources do not provide their electric power at line frequency and voltage, a DC bus is a useful common connection for several such sources. Due to the differences in output voltage among the sources, d...

  13. Network Extender for MIL-STD-1553 Bus

    Science.gov (United States)

    Marcus, Julius; Hanson, T. David

    2003-01-01

    An extender system for MIL-STD-1553 buses transparently couples bus components at multiple developer sites. The bus network extender is a relatively inexpensive system that minimizes the time and cost of integration of avionic systems by providing a convenient mechanism for early testing without the need to transport the usual test equipment and personnel to an integration facility. This bus network extender can thus alleviate overloading of the test facility while enabling the detection of interface problems that can occur during the integration of avionic systems. With this bus extender in place, developers can correct and adjust their own hardware and software before products leave a development site. Currently resident at Johnson Space Center, the bus network extender is used to test the functionality of equipment that, although remotely located, is connected through a MILSTD- 1553 bus. Inasmuch as the standard bus protocol for avionic equipment is that of MIL-STD-1553, companies that supply MIL-STD-1553-compliant equipment to government or industry and that need long-distance communication support might benefit from this network bus extender

  14. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2008-10-01

    This report provides preliminary results from a National Renewable Energy Laboratory evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment; early results and agency experience are also provided.

  15. Network Analysis of Urban Traffic with Big Bus Data

    CERN Document Server

    Zhao, Kai

    2016-01-01

    Urban traffic analysis is crucial for traffic forecasting systems, urban planning and, more recently, various mobile and network applications. In this paper, we analyse urban traffic with network and statistical methods. Our analysis is based on one big bus dataset containing 45 million bus arrival samples in Helsinki. We mainly address following questions: 1. How can we identify the areas that cause most of the traffic in the city? 2. Why there is a urban traffic? Is bus traffic a key cause of the urban traffic? 3. How can we improve the urban traffic systems? To answer these questions, first, the betweenness is used to identify the most import areas that cause most traffics. Second, we find that bus traffic is not an important cause of urban traffic using statistical methods. We differentiate the urban traffic and the bus traffic in a city. We use bus delay as an identification of the urban traffic, and the number of bus as an identification of the bus traffic. Third, we give our solutions on how to improve...

  16. Review of bus drivers' occupational stress and stress prevention

    NARCIS (Netherlands)

    Kompier, M.A.J.; Di Martino, V.

    1995-01-01

    Although heterogeneous in methodology and content, 32 studies from 13 countries on bus drivers' work and health are similar in their conclusions. Bus-driving–characterized by high demands, low control and low support – can be regarded as a classic example of high-strain occupation, with high risks o

  17. PWM ZCS DC Motor Drive and DC Power Supply

    OpenAIRE

    Bardia Montazeri

    2011-01-01

    Following the extension and increase in capacity of power electronic elements, many convertors with special applications have been designed. Convertors such as rectifiers, AC and DC power supplies, AC and DC drivers and so on. At present, optimization of these convertors, decreasing loss and bringing down the electromagnetic interference are desired. In this paper, a DC to DC convertor for controlling the speed  of DC motor is designed and  one prototype is presented in which switching losses...

  18. Djungle power. A more remote AC bus

    Energy Technology Data Exchange (ETDEWEB)

    Boehnke, Heinz W. [Technosol, Jork (Germany)

    2010-07-01

    The Dzanga-Sangha Reserve in the Central African Republic is probably one of the world's most remote protected rainforest areas, much to the benefit of the rare species of lowland gorilla, forest elephant and local pygmy population Ba'Aka. The park is co-managed by the ''WWF-World Wide Fund for Nature'' with sponsoring from the German Regenwald-Stiftung. In 2008 wwf decided to switch from the old, failing generator supply to a solar hybrid mini-grid, along with stringent measures of energy conservation and management. After a careful energy audit Technosol designed an AC-bus system with a 22 kWp PV generator which should overcome the dependency on the old generators and their fuel demands. For 15 buildings, an entirely new distribution network was installed, state of the art energy saving devices introduced and an energy metering system deviced. The installation is operating since August 2009. In such remote locations, the reliability of the AC-bus over other generator-based solutions will be demonstrated and with the support of international organisations like the wwf the practical application of solar hybrid supply becomes a landmark of sustainable energy concepts. (orig.)

  19. Memel's Batteries

    Directory of Open Access Journals (Sweden)

    Alexander F. Mitrofanov

    2015-12-01

    Full Text Available The article describes the history and equipment of the coastal and antiaircraft artillery batteries of German Navy (Kriegsmarine constructed in Memel area before and during the World War. There is given the brief description of the Soviet Navy stationed in the area in the postwar years.

  20. An Overview of Staged-bus Operation in Cities

    Directory of Open Access Journals (Sweden)

    Mohammad Hesam Hafezi

    2014-02-01

    Full Text Available In developing countries, demand for passenger travel is higher, due to economic growth. Government policy encourages people to use public transportation instead of their private carsto reduce of traffic congestion and air pollution. In the city areas, bus networks are the major part of the public transportation system because they are easily accessible and cheaper compared to other types of public transportation. In this study revelation of details of bus operation included different agents is studied. Bus operations, during provision of their service, have interaction with three main agents: bus agent, passenger agent and traffic agent. Study of the influence of each agent in bus operation is presented in this study, using the macroscopic way.

  1. Research on the Coordinated Design of Bus and Taxi Station

    Directory of Open Access Journals (Sweden)

    Jiangfeng Xi

    2015-01-01

    Full Text Available Rises in the number of transit buses, bus routes, and overall traffic volume in China’s cities, coupled with interference from other transport modes, such as taxis loading and unloading passengers nearby, have led to increasing traffic delays at bus stops, which is considered one of the factors degrading service levels and traffic operations on urban roadways. This paper studies traffic characteristics at bus stops, investigates variations in delay from different types or designs of bus stops, and analyzes the impact of it on traffic capacity, the purpose of which is to propose a solution to predicting the feasibility of an integrated design of bus stops and taxi stands with the help of mathematical models and based on the objectives of optimal traffic operations and passenger transfer.

  2. Improved design of HIRFL-CSR EVME bus controller

    International Nuclear Information System (INIS)

    The EVME bus controller which is a key component of the HIRFL-CSR control system was improved. Besides reconfiguring the embedded Linux, a utility program was developed for data exchange between the controller and the database. The bus controller is based on ARM920T(ARM9) micro processor which is BGA packaged. The bus controller has the universal interface of VGA display, keyboard, and mouse. The backboard interface logic is programmed in an in-system configurable FPGA device. The bus can drive high current up to 64 mA, with the flexibility of the programmable signal definitions. All the improved performance helped the EVME bus controller play a crucial role in HIRFL-CSR control system. (authors)

  3. Low back trouble among urban bus drivers in Denmark

    DEFF Research Database (Denmark)

    Netterstrøm, Bo; Juel, K

    1989-01-01

    The occurrence of low back trouble and possible connection with psychosocial conditions among urban bus drivers were studied using a questionnaire and subsequent registration of hospital discharges. 2,045 (83%) full-time male bus drivers in the three largest cities in Denmark answered a questionn......The occurrence of low back trouble and possible connection with psychosocial conditions among urban bus drivers were studied using a questionnaire and subsequent registration of hospital discharges. 2,045 (83%) full-time male bus drivers in the three largest cities in Denmark answered...... a questionnaire in 1978 regarding psychosocial factors and health. The prevalence of frequent low back pain was 57%. In a control group of 195 motormen the prevalence was 40%. Standardized Morbidity Ratio for bus drivers discharged from hospital during the period 1978-1984 with the diagnosis lumbar disc...

  4. DC-DC Type High-Frequency Link DC for Improved Power Quality of Cascaded Multilevel Inverter

    Science.gov (United States)

    Sadikin, Muhammad; Senjyu, Tomonobu; Yona, Atsushi

    2013-06-01

    Multilevel inverters are emerging as a new breed of power converter options for power system applications. Recent advances in power switching devices enabled the suitability of multilevel inverters for high voltage and high power applications because they are connecting several devices in series without the need of component matching. Usually, a transformerless battery energy storage system, based on a cascaded multilevel inverter, is used as a measure for voltage and frequency deviations. System can be reduced in size, weight, and cost of energy storage system. High-frequency link circuit topology is advantageous in realizing compact and light-weight power converters for uninterruptible power supply systems, new energy systems using photovoltaic-cells, fuel-cells and so on. This paper presents a DC-DC type high-frequency link DC (HFLDC) cascaded multilevel inverter. Each converter cell is implemented a control strategy for two H-bridge inverters that are controlled with the same multicarrier pulse width modulation (PWM) technique. The proposed cascaded multilevel inverter generates lower voltage total harmonic distortion (THD) in comparison with conventional cascaded multilevel inverter. Digital simulations are carried out using PSCAD/EMTDC to validate the performance of the proposed cascaded multilevel inverter.

  5. Batteries: Overview of Battery Cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Doeff, Marca M

    2010-07-12

    The very high theoretical capacity of lithium (3829 mAh/g) provided a compelling rationale from the 1970's onward for development of rechargeable batteries employing the elemental metal as an anode. The realization that some transition metal compounds undergo reductive lithium intercalation reactions reversibly allowed use of these materials as cathodes in these devices, most notably, TiS{sub 2}. Another intercalation compound, LiCoO{sub 2}, was described shortly thereafter but, because it was produced in the discharged state, was not considered to be of interest by battery companies at the time. Due to difficulties with the rechargeability of lithium and related safety concerns, however, alternative anodes were sought. The graphite intercalation compound (GIC) LiC{sub 6} was considered an attractive candidate but the high reactivity with commonly used electrolytic solutions containing organic solvents was recognized as a significant impediment to its use. The development of electrolytes that allowed the formation of a solid electrolyte interface (SEI) on surfaces of the carbon particles was a breakthrough that enabled commercialization of Li-ion batteries. In 1990, Sony announced the first commercial batteries based on a dual Li ion intercalation system. These devices are assembled in the discharged state, so that it is convenient to employ a prelithiated cathode such as LiCoO{sub 2} with the commonly used graphite anode. After charging, the batteries are ready to power devices. The practical realization of high energy density Li-ion batteries revolutionized the portable electronics industry, as evidenced by the widespread market penetration of mobile phones, laptop computers, digital music players, and other lightweight devices since the early 1990s. In 2009, worldwide sales of Li-ion batteries for these applications alone were US$ 7 billion. Furthermore, their performance characteristics (Figure 1) make them attractive for traction applications such as

  6. Batteries: Overview of Battery Cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Doeff, Marca M

    2010-07-12

    The very high theoretical capacity of lithium (3829 mAh/g) provided a compelling rationale from the 1970's onward for development of rechargeable batteries employing the elemental metal as an anode. The realization that some transition metal compounds undergo reductive lithium intercalation reactions reversibly allowed use of these materials as cathodes in these devices, most notably, TiS{sub 2}. Another intercalation compound, LiCoO{sub 2}, was described shortly thereafter but, because it was produced in the discharged state, was not considered to be of interest by battery companies at the time. Due to difficulties with the rechargeability of lithium and related safety concerns, however, alternative anodes were sought. The graphite intercalation compound (GIC) LiC{sub 6} was considered an attractive candidate but the high reactivity with commonly used electrolytic solutions containing organic solvents was recognized as a significant impediment to its use. The development of electrolytes that allowed the formation of a solid electrolyte interface (SEI) on surfaces of the carbon particles was a breakthrough that enabled commercialization of Li-ion batteries. In 1990, Sony announced the first commercial batteries based on a dual Li ion intercalation system. These devices are assembled in the discharged state, so that it is convenient to employ a prelithiated cathode such as LiCoO{sub 2} with the commonly used graphite anode. After charging, the batteries are ready to power devices. The practical realization of high energy density Li-ion batteries revolutionized the portable electronics industry, as evidenced by the widespread market penetration of mobile phones, laptop computers, digital music players, and other lightweight devices since the early 1990s. In 2009, worldwide sales of Li-ion batteries for these applications alone were US$ 7 billion. Furthermore, their performance characteristics (Figure 1) make them attractive for traction applications such as

  7. DESIGN AND IMPLEMENTATION OF CLOSED LOOP LCL-T RESONANT DC-TO-DC CONVERTER USING LOW COST EMBEDDED CONTROLLER

    OpenAIRE

    M. Annamalai; M. Vijaya Kumar

    2012-01-01

    The aim of this study is to simulate and implement open loop and closed loop controlled DC-DC converter for stand-alone wind energy system. Wind turbines, however, are not always very efficient in the wind speeds that are most common to a region. Typically, wind energy systems are designed to be highly efficient in high wind speed and have a cut-off wind speed- below which no energy is captured. In remote locations where wind energy is used for battery charging, the energy lost below the cut-...

  8. Comparative study of a small size wind generation system efficiency for battery charging

    Directory of Open Access Journals (Sweden)

    Mayouf Messaoud

    2013-01-01

    Full Text Available This paper presents an energetic comparison between two control strategies of a small size wind generation system for battery charging. The output voltage of the direct drive PMSG is connected to the battery through a switch mode rectifier. A DC-DC boost converter is used to regulate the battery bank current in order to achieve maximum power from the wind. A maximum powertracking algorithm calculates the current command that corresponds to maximum power output of the turbine. The DC-DC converter uses this current to calculate the duty cycle witch is necessary to control the pulse width modulated (PWM active switching device (IGPT. The system overview and modeling are presented including characteristics of wind turbine, generator, batteries, power converter, control system, and supervisory system. A simulation of the system is performed using MATLAB/SIMULINK.

  9. A Bidirectional, Triple-Voltage DC-DC Converter for Hybrid and Fuel Cell Vehicle Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

    2007-01-01

    Electrical power systems in future hybrid and fuel cell vehicles may employ three voltage (14V, 42V and high voltage (HV)) nets. These will be necessary to accommodate existing 14V loads as well as efficiently handle new heavy loads at the 42V net and an electrical traction drive on the HV bus. A low-cost bi-directional dc-dc converter was proposed in (10) for connecting the three voltage nets. The converter consists of two half-bridges and a high-frequency transformer; thus minimizing the number of switching devices and their associated gate driver components. One salient feature is that the half-bridge on the 42V bus is also utilized to provide the 14V bus by operating its duty ratio around an atypical value of 1/3. This eliminates the need for an additional 14V/42V converter. Moreover, it makes use of the parasitic capacitance of the switches and the transformer leakage inductance for soft-switching; no extra active switches or passive resonant components are required. The use of half-bridges makes the topology suitable for interleaved multi-phase configurations as a means to increase the power level because the capacitor legs can be shared. This paper presents simulation and experimental results on an interleaved two-phase arrangement rated at 4.5 kW. Also discussed are the benefits of operating with the atypical duty ratio on the transformer and a preferred multi-phase configuration to minimize capacitor ripple currents.

  10. 光储互补并离网一体逆变器控制策略%A control strategy of grid-connected and stand-alone converter integrated with photovoltaic and battery

    Institute of Scientific and Technical Information of China (English)

    罗潇; 李征

    2015-01-01

    随着新能源技术的发展,光伏发电受到越来越多人的关注。研究了一种光储互补并离网一体逆变器系统的控制策略,该系统由光伏组件、锂电池、电网和功率变换器组成。各个变换器独立工作,共同控制直流母线电压的稳定。分析了各个功率变换器的控制策略,实现了光伏储能并离网一体逆变器的稳定运行。%With the development of new energy resources, photovoltaic power generation system becomes more and more popular. A control strategy of grid-connected and stand-alone converter integrated with photovoltaic and battery system is researched. The system is composed of photovoltaic module, lithium battery, power grid and converters. They work individually and control the voltage of DC bus together.Paper studied each power converter's control strategy to achieve stable operation of the power generation system.

  11. DC / DC Converter for the conditioning of the photovoltaic energy - modeling and command strategy

    Directory of Open Access Journals (Sweden)

    Z. SABIRI

    2015-02-01

    Full Text Available Demand for energy, especially electricity, throughout the world, is increasingly growing rapidly. Renewable energy: wind, solar, geothermal, and hydroelectric and biomass provides substantial benefits for our climate, our health, and our economy. However it needs more investigations in terms of research. A special attention should be given on the optimization of energy production and its own integration in grids especially when the resources become multiple. The contribution of our researches is to study the technical and physical aspects to optimize the energy management in a multi-source system dedicated to rural area applications. The multi-source system is based on photovoltaic panels, wind turbine, solar PV and storage batteries. In this paper, we present the modeling and simulation of the part composed of photovoltaic source and its DC / DC converter.

  12. Analysis of Discontinuity Induced Bifurcations in a Dual Input DC-DC Converter

    Science.gov (United States)

    Giaouris, Damian; Banerjee, Soumitro; Mandal, Kuntal; Al-Hindawi, Mohammed M.; Abusorrah, Abdullah; Al-Turki, Yusuf; El Aroudi, Abdelali

    DC-DC power converters with multiple inputs and a single output are used in numerous applications where multiple sources, e.g. two or more renewable energy sources and/or a battery, feed a single load. In this work, a classical boost converter topology with two input branches connected to two different sources is chosen, with each branch independently being controlled by a separate peak current mode controller. We demonstrate for the first time that even though this converter is similar to other well known topologies that have been studied before, it exhibits many complex nonlinear behaviors that are not found in any other standard PWM controlled power converter. The system undergoes period incrementing cascade as a parameter is varied, with discontinuous hard transitions between consecutive periodicities. We show that the system can be described by a discontinuous map, which explains the observed bifurcation phenomena. The results have been experimentally validated.

  13. Design of high efficiency dual-mode buck DC-DC converter

    Energy Technology Data Exchange (ETDEWEB)

    Lai Xinquan; Zeng Huali; Ye Qiang; He Huisen; Zhang Shasha; Sun Yuqing, E-mail: zenghuali4213@126.com, E-mail: xqlai@mail.xidian.edu.cn [Institute of Electronic CAD, Xidian University, Xi' an 710071 (China)

    2010-11-15

    A buck DC-DC switching regulator with high efficiency is implemented by automatically altering the modulation mode according to load current, and it can operate with an input range of 4.5 to 30 V. At light load current, the converter operates in skip mode. The converter enters PWM mode operation with increasing load current. It reduces the switching loss at light load and standby state, which results in prolonging battery lifetime and stand-by time. Meanwhile, externally adjustable soft-start minimizes the inrush supply current and avoids the overshoot of output voltage at initial startup. The regulator is fabricated by a 0.6 {mu}m CDMOS process. The test results show that, under the condition of 3.3 V output, the efficiency is up to 64% at 5 mA and the maximum efficiency is 95.5%.

  14. Three-port DC-DC converter with new integrated transformer for DC Distribution Systems

    DEFF Research Database (Denmark)

    Ouyang, Ziwei; Andersen, Michael A. E.

    2014-01-01

    A new integrated transformer for three-port dc-dc converter is proposed to overcome the power coupling effect existed in some known multiple inputs dc-dc converters. Orthogonal primary windings arrangement and in series connection of diagonal secondary Windings enables a fully power decoupling...

  15. The Development and Verification of a Novel ECMS of Hybrid Electric Bus

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2014-01-01

    Full Text Available This paper presents the system modeling, control strategy design, and hardware-in-the-loop test for a series-parallel hybrid electric bus. First, the powertrain mathematical models and the system architecture were proposed. Then an adaptive ECMS is developed for the real-time control of a hybrid electric bus, which is investigated and verified in a hardware-in-the-loop simulation system. The ECMS through driving cycle recognition results in updating the equivalent charge and discharge coefficients and extracting optimized rules for real-time control. This method not only solves the problems of mode transition frequently and improves the fuel economy, but also simplifies the complexity of control strategy design and provides new design ideas for the energy management strategy and gear-shifting rules designed. Finally, the simulation results show that the proposed real-time A-ECMS can coordinate the overall hybrid electric powertrain to optimize fuel economy and sustain the battery SOC level.

  16. 直流模块式光伏发电系统前级DC/DC变换研究%Research on Front-end DC/DC Converter of DC Module Photovoltaic Generation System

    Institute of Scientific and Technical Information of China (English)

    陈双; 陈卫民; 严虹

    2012-01-01

    For the existing problems of centralized photovoltaic power system structure, DC module photovoltaic power system structure is introduced and the flyback converter is taken as the front-end DC module of the DC module photovoltaic power system. A variable-step hysteresis comparison method is adopted to realize the maximum power point tracking control, and a voltage close-loop control strategy with voltage feed-forward control is used to stabilize the DC bus voltage. The experimental results demonstrate the feasilibity of the solution scheme.%针对传统集中式光伏发电系统结构存在的问题,介绍了直流模块式光伏发电结构,并利用反激变换器作为直流模块式光伏发电系统的前级直流模块,采用变步长的滞环比较法实现光伏电池的最大功率跟踪控制,采用带有输入电压前馈控制的电压闭环控制策略实现直流母线的稳压控制.试验结果表明,该方案可行.

  17. The Shortest Path Problems in Battery-Electric Vehicle Dispatching with Battery Renewal

    Directory of Open Access Journals (Sweden)

    Minfang Huang

    2016-06-01

    Full Text Available Electric vehicles play a key role for developing an eco-sustainable transport system. One critical component of an electric vehicle is its battery, which can be quickly charged or exchanged before it runs out. The problem of electric vehicle dispatching falls into the category of the shortest path problem with resource renewal. In this paper, we study the shortest path problems in (1 electric transit bus scheduling and (2 electric truck routing with time windows. In these applications, a fully-charged battery allows running a limited operational distance, and the battery before depletion needs to be quickly charged or exchanged with a fully-charged one at a battery management facility. The limited distance and battery renewal result in a shortest path problem with resource renewal. We develop a label-correcting algorithm with state space relaxation to find optimal solutions. In the computational experiments, real-world road geometry data are used to generate realistic travel distances, and other types of data are obtained from the real world or randomly generated. The computational results show that the label-correcting algorithm performs very well.

  18. Batteries for Electric Vehicles

    Science.gov (United States)

    Conover, R. A.

    1985-01-01

    Report summarizes results of test on "near-term" electrochemical batteries - (batteries approaching commercial production). Nickel/iron, nickel/zinc, and advanced lead/acid batteries included in tests and compared with conventional lead/acid batteries. Batteries operated in electric vehicles at constant speed and repetitive schedule of accerlerating, coasting, and braking.

  19. Battery Safety Basics

    Science.gov (United States)

    Roy, Ken

    2010-01-01

    Batteries commonly used in flashlights and other household devices produce hydrogen gas as a product of zinc electrode corrosion. The amount of gas produced is affected by the batteries' design and charge rate. Dangerous levels of hydrogen gas can be released if battery types are mixed, batteries are damaged, batteries are of different ages, or…

  20. The wheels on the bus go "buy buy buy": school bus advertising laws.

    Science.gov (United States)

    Pomeranz, Jennifer L

    2012-09-01

    School buses, a practical necessity for millions of children, are at the center of new efforts to raise revenue. School bus advertising laws bring public health and commercialization concerns to the school setting. In doing so, they potentially expose school districts to First Amendment lawsuits. I examined various school bus advertising bills and laws. I reviewed First Amendment "forum analysis" as applied in the transit and school settings to clarify how this legal test may affect school districts subject to such laws. I have made recommendations for school districts to enact appropriate policies to ensure that such advertising does not undermine public health and to enable the districts to maintain control over their property.

  1. Parameter Matching and Simulation of a Plug-in Hybrid Electric City Bus%Plug—in混合动力城市公交车参数匹配与仿真

    Institute of Scientific and Technical Information of China (English)

    杨攀; 赵又群

    2011-01-01

    We rebuild a conventional city bus to a parallel plug-in hybrid electric city bus, and the structure and parameters of the power system are designed. Ni-MH battery and permanent magnet synchronous motor are used in this hybrid electric city bus. Based on the result of simulation in ADVISOR, the plug-in hybrid electric bus has almost equal kinetic performance to the prototype bus, but the fuel economy increases by at least 20% compared with the prototype bus.%将一种传统城市公交车改造成单轴并联结构的Plug-in混合动力公交车,并对动力系统进行参数匹配和设计。该混合动力公交车的储能原件采用镍氢电池,电机采用永磁同步电机。在电动汽车仿真软件ADVISOR中进行建模仿真的结果表明,Plug-in混合动力公交车的动力性与原型车相当,经济性与原型车相比提高了20%以上,达到了预期开发设计的目标。

  2. Implementation of a Small Type DC Microgrid Based on Fuzzy Control and Dynamic Programming

    Directory of Open Access Journals (Sweden)

    Chin-Hsing Cheng

    2016-09-01

    Full Text Available A DC microgrid (DC-MG is a novel power system that uses DC distribution in order to provide high quality power. The study system is made by a photovoltaic array (PV, a wind generator (WG, a fuel cell (FC, and an energy storage system (ESS to establish a small type DC microgrid, with the bus being established by DC/DC converters with fuzzy controllers. An overall power dispatch was designed for the proposed system to distribute the power flows among the different energy sources and the storage unit in the system in order to satisfy the load requirements throughout an entire 24-h period. The structure of a power supervisor based on an optimal power dispatch algorithm is here proposed. Optimization was performed using dynamic programming (DP. In this paper, a system configuration of a DC microgrid is analyzed in different scenarios to show the efficacy of the control for all devices for the variable weather conditions with different DC loads. Thus, the voltage level and the power flow of the system are shown for different load conditions.

  3. Design, Operation, Control, and Economics of a Photovoltaic/Fuel Cell/Battery Hybrid Renewable Energy System for Automotive Applications

    Directory of Open Access Journals (Sweden)

    Zachary S. Whiteman

    2015-06-01

    Full Text Available Meeting rapidly growing global energy demand—without producing greenhouse gases or further diminishing the availability of non-renewable resources—requires the development of affordable low-emission renewable energy systems. Here, we develop a hybrid renewable energy system (HRES for automotive applications—specifically, a roof-installed photovoltaic (PV array combined with a PEM fuel cell/NiCd battery bus currently operating shuttle routes on the University of Delaware campus. The system’s overall operating objectives—meeting the total power demand of the bus and maintaining the desired state of charge (SOC of the NiCd battery—are achieved with appropriately designed controllers: a logic-based “algebraic controller” and a standard PI controller. The design, implementation, and performance of the hybrid system are demonstrated via simulation of real shuttle runs under various operating conditions. The results show that both control strategies perform equally well in enabling the HRES to meet its objectives under typical operating conditions, and under sudden cloud cover conditions; however, at consistently high bus speeds, battery SOC maintenance is better, and the system consumes less hydrogen, with PI control. An economic analysis of the PV investment necessary to realize the HRES design objectives indicates a return on investment of approximately 30% (a slight, but nonetheless positive, ~$550 profit over the bus lifetime in Newark, DE, establishing the economic viability of the proposed addition of a PV array to the existing University of Delaware fuel cell/battery bus.

  4. Parameters Matching and Performance Analysis of Power System on Pure Electric Bus%纯电动客车动力系统参数匹配及性能分析

    Institute of Scientific and Technical Information of China (English)

    王燕燕

    2011-01-01

    以纯电动客车为研究对象,对动力传动系统,主要对驱动电动机、变速器以及动力电池参数进行合理地计算和设计。为纯电动客车动力传动系统的初步选型提供依据。%Taking the pure electric bus as the study object, the parameters of driving motor, transmission and power battery are calculated and designed so as to provide the basis for lectotype of power transmission system on pure electric bus.

  5. Bus bar electrical feedthrough for electrorefiner system

    Science.gov (United States)

    Williamson, Mark; Wiedmeyer, Stanley G; Willit, James L; Barnes, Laurel A; Blaskovitz, Robert J

    2013-12-03

    A bus bar electrical feedthrough for an electrorefiner system may include a retaining plate, electrical isolator, and/or contact block. The retaining plate may include a central opening. The electrical isolator may include a top portion, a base portion, and a slot extending through the top and base portions. The top portion of the electrical isolator may be configured to extend through the central opening of the retaining plate. The contact block may include an upper section, a lower section, and a ridge separating the upper and lower sections. The upper section of the contact block may be configured to extend through the slot of the electrical isolator and the central opening of the retaining plate. Accordingly, relatively high electrical currents may be transferred into a glovebox or hot-cell facility at a relatively low cost and higher amperage capacity without sacrificing atmosphere integrity.

  6. Inductor Compensation in Three Phase PFC Control with Decoupling the Input Voltage and Bus Voltage

    Directory of Open Access Journals (Sweden)

    Luo Guang

    2016-01-01

    Full Text Available As the nonlinear structure of the boost ac/dc topology, the PFC is difficult to be controlled. The average state space theory has revealed that the choke current is determined by duty-ratio coupled with input voltage and bus voltage, which makes the high-performance sine-wave current track control more challenging. To remove disturbing variables and reduce the zero-crossing distortion, the decoupling control strategy is presented. Also, it is shown in this paper that the variable inductance has a great influence on PFC and THDI. As the inductor in boost converter varies with the current, a compensating coefficient of current is also proposed. The decoupling strategy and the inductor compensation strategy are implemented on a UPS with three phase input voltage. Numerical simulation and experimental results has indicated the high-performance of these control strategy.

  7. A NOVEL CHARGE AND DISCHARGE EQUALIZATION SCHEME FOR BATTERY STRINGS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A novel charge/discharge equalization scheme is proposed in thispaper. According to the states of batteries, two equalizing methods are adopted for equalization during different charging and discharging phases. A switched capacitor is utilized during high rate charging and discharging. During the later period of charging and discharging, an auxiliary low power DC/DC converter and the inherent switch modules of a control/monitor unit are used. So it is very simple and efficient. With the developed equalizer, the lifetime of a series battery string can be extended.

  8. Swisstrolley 3 - An articulated trolley bus; SWISSTROLLEY 3. Gelenktrolleybus

    Energy Technology Data Exchange (ETDEWEB)

    Gisler, H.-J.

    2006-07-01

    This illustrated final report for the Swiss Federal Office of Energy (SFOE) takes a look at the Swisstrolley 3 low-floor, articulated trolley bus developed in Switzerland by the Hess AG company. Various features of the variants of the trolley bus, including single vehicle, single and double-articulated buses and bus trailers, are discussed. The reductions achieved in energy consumption, weight and noise are discussed. Typical values for power consumption are presented in graphical form. Economic viability and passenger-friendliness are examined, as are possibilities for further improvement.

  9. Statistical Analysis for the Driving Cycle of Beijing's Bus

    Institute of Scientific and Technical Information of China (English)

    王震坡; 孙逢春; 王军; 孙立清

    2004-01-01

    According to the test data of the driving model for Beijing's bus routes, 9 parameters and the actual values of Beijing bus are confirmed to evaluate the driving cycle, 2 ways of establishing driving cycle model are analyzed, the formula of calculating driving cycle is acquired, and the calculating driving cycle model and the statistical driving cycle model for the buses in Beijing urban areas are set up. This study provides scientific basis for selecting the bus type and confirming the design parameters and the running method in Beijing.

  10. Development in Conducting Bus of RE-Al Alloys

    Institute of Scientific and Technical Information of China (English)

    李德富; 胡捷; 章萍芝; 石瑛; 李彦利

    2001-01-01

    Four kinds of deformed aluminum alloys were tested. One kind of RE-A1-Mg-Si alloy, which possessed high conductivity and strength, was the first priority by contrast test, The large specification bus of conducting aluminum all oys was made by thermomechanical process during the industrial experiment. The properties of the bus are as follows:the tensile strength σb is 238 MPa, the conductivity (v.s. IACS) is 54.3%, and the current-carrying capacity is beyond 3.1kA during working process. This kind of RE-Al alloy bus has been applied to several electrical transmitting and transforming work.

  11. A new MV bus transfer scheme for nuclear power plants

    Directory of Open Access Journals (Sweden)

    Chang Choong-Koo

    2015-01-01

    Full Text Available Fast bus transfer method is the most popular and residual voltage transfer method that is used as a backup in medium voltage buses in general. The use of the advanced technology like open circuit voltage prediction and digital signal processing algorithms can improve the reliability of fast transfer scheme. However, according to the survey results of the recent operation records in nuclear power plants, there were many instances where the fast transfer scheme has failed. To assure bus transfer in any conditions and circumstances, uninterruptible bus transfer scheme utilizing the state of the art medium voltage UPS is discussed and elaborated.

  12. DC Distributed Power Systems. Analysis, Design and Control for a Renewable Energy System

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Per

    2002-12-01

    Renewable energy systems are likely to become wide spread in the future due to environmental demands. As a consequence of the dispersed nature of renewable energy systems, this implies that there will be a distributed generation of electric power. Since most of the distributed electrical energy sources do not provide their electric power at line frequency and voltage, a DC bus is a useful common connection for several such sources. Due to the differences in output voltage among the sources, depending on both the type of source and their actual operating point, the sources are connected to the DC power system via power electronic converters. The intention behind the presented work is not to replace the existing AC power system, but to include local DC power systems. The AC and DC power systems are connected at some points in the network. The renewable energy sources are weak compared to the present hydro power and nuclear power plants, resulting in a need of power conditioning before the renewable energy is fed to the transmission lines. The benefit of such an approach is that power conditioning is applied on a central level, i.e. at the interface between the AC and DC power systems. The thesis starts with an overview of related work. Present DC transmission systems are discussed and investigated in simulations. Then, different methods for load sharing and voltage control are discussed. Especially, the voltage droop control scheme is examined thoroughly. Since the droop control method does not require any high-speed communication between sources and loads, this is considered the most suitable for DC distributed power systems. The voltage feed back design of the controller also results in a specification of the DC bus capacitors (equivalents to DC link capacitors of single converters) needed for filtering. If the converters in the DC distribution system are equipped with capacitors selected from this design criterion and if the DC bus impedance is neglected, the

  13. DC Distributed Power Systems. Analysis, Design and Control for a Renewable Energy System

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Per

    2002-12-01

    Renewable energy systems are likely to become wide spread in the future due to environmental demands. As a consequence of the dispersed nature of renewable energy systems, this implies that there will be a distributed generation of electric power. Since most of the distributed electrical energy sources do not provide their electric power at line frequency and voltage, a DC bus is a useful common connection for several such sources. Due to the differences in output voltage among the sources, depending on both the type of source and their actual operating point, the sources are connected to the DC power system via power electronic converters. The intention behind the presented work is not to replace the existing AC power system, but to include local DC power systems. The AC and DC power systems are connected at some points in the network. The renewable energy sources are weak compared to the present hydro power and nuclear power plants, resulting in a need of power conditioning before the renewable energy is fed to the transmission lines. The benefit of such an approach is that power conditioning is applied on a central level, i.e. at the interface between the AC and DC power systems. The thesis starts with an overview of related work. Present DC transmission systems are discussed and investigated in simulations. Then, different methods for load sharing and voltage control are discussed. Especially, the voltage droop control scheme is examined thoroughly. Since the droop control method does not require any high-speed communication between sources and loads, this is considered the most suitable for DC distributed power systems. The voltage feed back design of the controller also results in a specification of the DC bus capacitors (equivalents to DC link capacitors of single converters) needed for filtering. If the converters in the DC distribution system are equipped with capacitors selected from this design criterion and if the DC bus impedance is neglected, the

  14. DC-DC powering for the CMS pixel upgrade

    Science.gov (United States)

    Feld, Lutz; Fleck, Martin; Friedrichs, Marcel; Hensch, Richard; Karpinski, Waclaw; Klein, Katja; Rittich, David; Sammet, Jan; Wlochal, Michael

    2013-12-01

    The CMS experiment plans to replace its silicon pixel detector with a new one with improved rate capability and an additional detection layer at the end of 2016. In order to cope with the increased number of detector modules the new pixel detector will be powered via DC-DC converters close to the sensitive detector volume. This paper reviews the DC-DC powering scheme and reports on the ongoing R&D program to develop converters for the pixel upgrade. Design choices are discussed and results from the electrical and thermal characterisation of converter prototypes are shown. An emphasis is put on system tests with up to 24 converters. The performance of pixel modules powered by DC-DC converters is compared to conventional powering. The integration of the DC-DC powering scheme into the pixel detector is described and system design issues are reviewed.

  15. DC-DC Powering for the CMS Pixel Upgrade

    CERN Document Server

    Feld, Lutz Werner; Marcel Friedrichs; Richard Hensch; Karpinski, Waclaw; Klein, Katja; Rittich, David Michael; Sammet, Jan Domenik; Wlochal, Michael

    2013-01-01

    The CMS experiment plans to replace its silicon pixel detector with a new one with improved rate capability and an additional detection layer at the end of 2016. In order to cope with the increased number of detector modules the new pixel detector will be powered via DC-DC converters close to the sensitive detector volume. This paper reviews the DC-DC powering scheme and reports on the ongoing R and D program to develop converters for the pixel upgrade. Design choices are discussed and results from the electrical and thermal characterisation of converter prototypes are shown. An emphasis is put on system tests with up to24 converters. The performance of pixel modules powered by DC-DC converters is compared to conventional powering. The integration of the DC-DC powering scheme into the pixel detector is described and system design issues are reviewed.

  16. Global Precipitation Measurement (GPM) Spacecraft Lithium Ion Battery Micro-Cycling Investigation

    Science.gov (United States)

    Dakermanji, George; Lee, Leonine; Spitzer, Thomas

    2016-01-01

    The Global Precipitation Measurement (GPM) spacecraft was jointly developed by NASA and JAXA. It is a Low Earth Orbit (LEO) spacecraft launched on February 27, 2014. The power system is a Direct Energy Transfer (DET) system designed to support 1950 watts orbit average power. The batteries use SONY 18650HC cells and consist of three 8s by 84p batteries operated in parallel as a single battery. During instrument integration with the spacecraft, large current transients were observed in the battery. Investigation into the matter traced the cause to the Dual-Frequency Precipitation Radar (DPR) phased array radar which generates cyclical high rate current transients on the spacecraft power bus. The power system electronics interaction with these transients resulted in the current transients in the battery. An accelerated test program was developed to bound the effect, and to assess the impact to the mission.

  17. Single Switched Capacitor Battery Balancing System Enhancements

    Directory of Open Access Journals (Sweden)

    Joeri van Mierlo

    2013-04-01

    Full Text Available Battery management systems (BMS are a key element in electric vehicle energy storage systems. The BMS performs several functions concerning to the battery system, its key task being balancing the battery cells. Battery cell unbalancing hampers electric vehicles’ performance, with differing individual cell voltages decreasing the battery pack capacity and cell lifetime, leading to the eventual failure of the total battery system. Quite a lot of cell balancing topologies have been proposed, such as shunt resistor, shuttling capacitor, inductor/transformer based and DC energy converters. The shuttling capacitor balancing systems in particular have not been subject to much research efforts however, due to their perceived low balancing speed and high cost. This paper tries to fill this gap by briefly discussing the shuttling capacitor cell balancing topologies, focusing on the single switched capacitor (SSC cell balancing and proposing a novel procedure to improve the SSC balancing system performance. This leads to a new control strategy for the SSC system that can decrease the balancing system size, cost, balancing time and that can improve the SSC balancing system efficiency.

  18. Common Traffic Violations of Bus Drivers in Urban China: An Observational Study

    OpenAIRE

    Qiqi Wang; , Wei Zhang; Rendong Yang; Yuanxiu Huang; Lin Zhang; Peishan Ning; Xunjie Cheng; Schwebel, David C; Guoqing Hu; Hongyan Yao

    2015-01-01

    Objective To report common traffic violations in bus drivers and the factors that influence those violations in urban China. Methods We conducted an observational study to record three types of traffic violations among bus drivers in Changsha City, China: illegal stopping at bus stations, violating traffic light signals, and distracted driving. The behaviors of bus drivers on 32 routes (20% of bus routes in the city) were observed. A two-level Poisson regression examined factors that predicte...

  19. Rfid-Based Automatic Bus Ticketing: Features and Trends

    Science.gov (United States)

    Oudah, A.

    2016-02-01

    Recent advancements in various technologies have made remarkable developments in various fields for public welfare and public transport is one such area. In the near future public bus transport system with advanced technologies like Radio Frequency Identification Device (RFID), GSM, GPS, ZigBee and RF modules will gain spotlight due to their advantage of higher convenience and greater life standards as compared to the conventional bus systems. In this paper, a comprehensive review of all several proposed bus ticketing and bus information methods has been presented in detail. The study brings out improved solution in terms of cost, convenience, user satisfaction and future implementation. The choice of working modules and their efficient performance has been discussed along with the highlighted importance of the need of technology for welfare of common public and visually impaired.

  20. Constant of heat conduction and stabilization of bus bar conductor

    Science.gov (United States)

    López, G.

    Using the one-dimensional, time-independent conduction state, a constant of heat conduction is given bringing about the known stabilization theorem and a closed expression for the bus bar to be cryogenically stable in superconducting accelerators.

  1. Black silicon solar cells with black bus-bar strings

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Tang, Peter Torben; Mizushima, Io;

    2016-01-01

    We present the combination of black silicon texturing and blackened bus-bar strings as a potential method for obtaining all-black solar panels, while using conventional, front-contacted solar cells. Black silicon was realized by maskless reactive ion etching resulting in total, average reflectance...... below 0.5% across a 156x156 mm2 silicon wafer. Four different methods to obtain blackened bus-bar strings were compared with respect to reflectance, and two of these methods (i.e., oxidized copper and etched solder) were used to fabricate functional allblack solar 9-cell panels. The black bus-bars (e.......g., by oxidized copper) have a reflectance below 3% in the entire visible wavelength range. The combination of black silicon cells and blackened bus-bars results in aesthetic, all-black panels based on conventional, front-contacted solar cells without compromising efficiency....

  2. Optimization Model for Headway of a Suburban Bus Route

    Directory of Open Access Journals (Sweden)

    Xiaohong Jiang

    2014-01-01

    Full Text Available Due to relatively low passenger demand, headways of suburban bus route are usually longer than those of urban bus route. Actually it is also difficult to balance the benefits between passengers and operators, subject to the service standards from the government. Hence the headway of a suburban bus route is usually determined on the empirical experience of transport planners. To cope with this problem, this paper proposes an optimization model for designing the headways of suburban bus routes by minimizing the operating and user costs. The user costs take into account both the waiting time cost and the crowding cost. The feasibility and validity of the proposed model are shown by applying it to the Route 206 in Jiangning district, Nanjing city of China. Weightages of passengers’ cost and operating cost are further discussed, considering different passenger flows. It is found that the headway and objective function are affected by the weightages largely.

  3. Optimal control system of the intermittent bus-only approach

    Institute of Scientific and Technical Information of China (English)

    Jie Jiang; Yulin Chang

    2014-01-01

    To guarantee bus priority with a minimum impact on car traffic at intersections, an optimal control system of the intermittent bus-only approach (IBA) was proposed. The problems of the existing system are first solved through optimization: the judgment time of the IBA system was advanced to allow a bus to jump car queues if the bus was detected to arrive at the intersection, and the instant that the IBA lane became available to cars was controlled dynamically to increase the capacity of the IBA lane. The total car delay in one cycle was then analyzed quantitatively when implementing the optimal control system. The results show that in comparison with the existing system of the IBA, the car delay is greatly reduced and the probability of a car stopping twice is low after optimizing the IBA system.

  4. Study on the Bus Real-time Dispatching Model

    Institute of Scientific and Technical Information of China (English)

    YingZou; JianguoLi; JianhuaHuang; ZhenminTang

    2004-01-01

    The real-time dispatching model on bus system is studied in this article. Realtime dispatching can resume the planned schedule quickly, and then to ensure the reliability of the public transport service and to well raise the service quality.

  5. Global Optimization for Bus Line Timetable Setting Problem

    Directory of Open Access Journals (Sweden)

    Qun Chen

    2014-01-01

    Full Text Available This paper defines bus timetables setting problem during each time period divided in terms of passenger flow intensity; it is supposed that passengers evenly arrive and bus runs are set evenly; the problem is to determine bus runs assignment in each time period to minimize the total waiting time of passengers on platforms if the number of the total runs is known. For such a multistage decision problem, this paper designed a dynamic programming algorithm to solve it. Global optimization procedures using dynamic programming are developed. A numerical example about bus runs assignment optimization of a single line is given to demonstrate the efficiency of the proposed methodology, showing that optimizing buses’ departure time using dynamic programming can save computational time and find the global optimal solution.

  6. Bus Passenger Recognition and Track of Video Sequence

    Directory of Open Access Journals (Sweden)

    Donghua Zhou

    2013-06-01

    Full Text Available Study on bus passenger recognition and track of video sequence is a research aiming at realizing making a statistics on passenger flow volume of bus, which not only helps traffic services center rationally schedule vehicles, but also can avoid overload. The system makes machine vision technology and digital image processing technique applied in customer counting of bus. The key questions in the study include effective collection of video image, effective extraction of moving object in sequence images, recognition of moving targets, trace and count of moving objects. The paper makes deep analysis on relevant technology from the perspective of the theory and practical application of the algorithm, and the study makes achievements. The theoretical algorithm for the study on bus passenger recognition and track of video sequence is distinctive. The practical experiments indicate that the system can satisfy the real-time requirements, and can accurately make statistics on the number of passengers, which has great application value.

  7. Development of Contact-Wireless Type Railcar by Lithium Ion Battery

    OpenAIRE

    Ogihara, Takashi

    2010-01-01

    Large lithium ion battery was developed for the running of railcar. Mn type lithium ion battery was used because of low cost and higher safety. LMP with high rechargeable performance were produced by large flame type spray pyrolysis. The laminate sheet type lithium ion cell was made using LMP. Various type large lithium ion battery modules consisted of submodule, in which laminate sheet type lithium ion cells were connected in series and parallel, were constructed. The running test of DC and ...

  8. Standby battery requirements for telecommunications power

    Science.gov (United States)

    May, G. J.

    The requirements for standby power for telecommunications are changing as the network moves from conventional systems to Internet Protocol (IP) telephony. These new systems require higher power levels closer to the user but the level of availability and reliability cannot be compromised if the network is to provide service in the event of a failure of the public utility. Many parts of these new networks are ac rather than dc powered with UPS systems for back-up power. These generally have lower levels of reliability than dc systems and the network needs to be designed such that overall reliability is not reduced through appropriate levels of redundancy. Mobile networks have different power requirements. Where there is a high density of nodes, continuity of service can be reasonably assured with short autonomy times. Furthermore, there is generally no requirement that these networks are the provider of last resort and therefore, specifications for continuity of power are directed towards revenue protection and overall reliability targets. As a result of these changes, battery requirements for reserve power are evolving. Shorter autonomy times are specified for parts of the network although a large part will continue to need support for hours rather minutes. Operational temperatures are increasing and battery solutions that provide longer life in extreme conditions are becoming important. Different battery technologies will be discussed in the context of these requirements. Conventional large flooded lead/acid cells both with pasted and tubular plates are used in larger central office applications but the majority of requirements are met with valve-regulated lead/acid (VRLA) batteries. The different types of VRLA battery will be described and their suitability for various applications outlined. New developments in battery construction and battery materials have improved both performance and reliability in recent years. Alternative technologies are also being proposed

  9. Decentralized Control Strategy for PV Based DC Microgrid with Hybrid Storage

    Directory of Open Access Journals (Sweden)

    Biswas Ishita

    2016-01-01

    Full Text Available Due to the rapid development of power electronics technology and modernization of DC based loads, DC microgrids (DCMG are becoming most attractive solution in terms of their increased efficiency and high power quality. However they face certain challenges like intermittency of renewable energy sources, limitations in dynamic behaviour of storage systems and various stability issues during islanding. Thus it is mandatory to select the DCMG components properly with a robust control strategy for power converters in order to maintain power balance despite of variation in source and load power in order maintain the system power quality. In this work, a DC bus signalling based decentralized control strategy is proposed for a PV based DCMG, which eliminates the risk associated with DC bus voltage fluctuation. Fuel cell is as an auxiliary power source along with solar PV and storage devices, reduces the possibility of black out and helps to increase system reliability. The proposed control strategy has been validated through MATLAB/Simulink based simulation studies for variable weather condition and load demand on DCMG system.

  10. Isolated Bidirectional DC Converters for Distributed Battery Energy Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Power systems are the core heartbeat of any advanced vehicle. Reliability and flexibility of these systems are therefore of the highest priority. This Phase 1...

  11. Compressed natural gas bus safety: a quantitative risk assessment.

    Science.gov (United States)

    Chamberlain, Samuel; Modarres, Mohammad

    2005-04-01

    This study assesses the fire safety risks associated with compressed natural gas (CNG) vehicle systems, comprising primarily a typical school bus and supporting fuel infrastructure. The study determines the sensitivity of the results to variations in component failure rates and consequences of fire events. The components and subsystems that contribute most to fire safety risk are determined. Finally, the results are compared to fire risks of the present generation of diesel-fueled school buses. Direct computation of the safety risks associated with diesel-powered vehicles is possible because these are mature technologies for which historical performance data are available. Because of limited experience, fatal accident data for CNG bus fleets are minimal. Therefore, this study uses the probabilistic risk assessment (PRA) approach to model and predict fire safety risk of CNG buses. Generic failure data, engineering judgments, and assumptions are used in this study. This study predicts the mean fire fatality risk for typical CNG buses as approximately 0.23 fatalities per 100-million miles for all people involved, including bus passengers. The study estimates mean values of 0.16 fatalities per 100-million miles for bus passengers only. Based on historical data, diesel school bus mean fire fatality risk is 0.091 and 0.0007 per 100-million miles for all people and bus passengers, respectively. One can therefore conclude that CNG buses are more prone to fire fatality risk by 2.5 times that of diesel buses, with the bus passengers being more at risk by over two orders of magnitude. The study estimates a mean fire risk frequency of 2.2 x 10(-5) fatalities/bus per year. The 5% and 95% uncertainty bounds are 9.1 x 10(-6) and 4.0 x 10(-5), respectively. The risk result was found to be affected most by failure rates of pressure relief valves, CNG cylinders, and fuel piping.

  12. Bus Implementation Using New Low Power PFSCL Tristate Buffers

    OpenAIRE

    Neeta Pandey; Bharat Choudhary; Kirti Gupta; Ankit Mittal

    2016-01-01

    This paper proposes new positive feedback source coupled logic (PFSCL) tristate buffers suited to bus applications. The proposed buffers use switch to attain high impedance state and modify the load or the current source section. An interesting consequence of this is overall reduction in the power consumption. The proposed tristate buffers consume half the power compared to the available switch based counterpart. The issues with available PFSCL tristate buffers based bus implementation are id...

  13. Collecting battery data with Open Battery

    OpenAIRE

    Jones, Gareth L.; Harrison, Peter G.

    2012-01-01

    In this paper we present Open Battery, a tool for collecting data on mobile phone battery usage, describe the data we have collected so far and make some observations. We then introduce the fluid queue model which we hope may prove a useful tool in future work to describe mobile phone battery traces.

  14. Very low noise AC/DC power supply systems for large detector arrays

    Science.gov (United States)

    Arnaboldi, C.; Baù, A.; Carniti, P.; Cassina, L.; Giachero, A.; Gotti, C.; Maino, M.; Passerini, A.; Pessina, G.

    2015-12-01

    In this work, we present the first part of the power supply system for the CUORE and LUCIFER arrays of bolometric detectors. For CUORE, it consists of AC/DC commercial power supplies (0-60 V output) followed by custom DC/DC modules (48 V input, ±5 V to ±13.5 V outputs). Each module has 3 floating and independently configurable output voltages. In LUCIFER, the AC/DC + DC/DC stages are combined into a commercial medium-power AC/DC source. At the outputs of both setups, we introduced filters with the aim of lowering the noise and to protect the following stages from high voltage spikes that can be generated by the energy stored in the cables after the release of accidental short circuits. Output noise is very low, as required: in the 100 MHz bandwidth the RMS level is about 37 μVRMS (CUORE setup) and 90 μVRMS (LUCIFER setup) at a load of 7 A, with a negligible dependence on the load current. Even more importantly, high frequency switching disturbances are almost completely suppressed. The efficiency of both systems is above 85%. Both systems are completely programmable and monitored via CAN bus (optically coupled).

  15. Hierarchical Control for Multiple DC Microgrids Clusters

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Dragicevic, Tomislav; Vasquez, Juan Carlos;

    2014-01-01

    droop coefficients according to the state-of-charge (SOC) of batteries automatically. A small signal model is developed to investigate effects of the system parameters, constant power loads as well as line impedance between the MGs on stability of these systems. In the secondary level, a distributed....... Another distributed policy is employed then to regulate the power flow among the MGs according to their local SOCs. The proposed distributed controllers on each MG communicate with only the neighbor MGs through a communication infrastructure. Finally, the small signal model is expanded for dc MG clusters...... consensus-based voltage regulator is introduced to eliminate the average voltage deviation over the MGs. This distributed averaging method allows the power flow control between the MGs to be achieved at the same time, as it can be accomplished only at the cost of having voltage deviation inside the system...

  16. Control of improved full-bridge three-level DC/DC converter for wind turbines in a DC grid

    DEFF Research Database (Denmark)

    Deng, Fujin; Chen, Zhe

    2013-01-01

    This paper presents an improved full-bridge three-level (IFBTL) dc/dc converter for a wind turbine in a dc grid by inserting a passive filter into the dc/dc converter to improve the performance of the converter. The passive filter can effectively reduce the voltage stress of the medium frequency...... transformer in the IFBTL dc/dc converter. A modulation strategy, including two operation modes, is proposed for the IFBTL dc/dc converter. Then, a voltage balancing control strategy is proposed for the IFBTL dc/dc converter. Furthermore, the control of the wind turbine based on the IFBTL dc/dc converter...... in a dc-grid system is presented. Finally, a small-scale IFBTL dc/dc converter prototype was built and tested in the laboratory, and the results verify the theoretical analysis....

  17. Ultra-Capacitor Energy Storage in a Large Hybrid Electric Bus

    Science.gov (United States)

    Viterna, L. A.

    1997-01-01

    The power requirements for inner city transit buses are characterized by power peaks about an order of magnitude larger than the average power usage of the vehicle. For these vehicles, hybrid power trains can offer significantly improved fuel economy and exhaust emissions. A critical design challenge, however, has been developing the energy storage and power management system to respond to these rapid power variations. Most hybrid vehicles today use chemical energy storage batteries to supplement the power from the fuel burning generator unit. Chemical storage batteries however, present several difficulties in power management and control. These difficulties include (1) inadequate life, (2) limited current delivery as well as absorption during regenerative braking, (3) inaccurate measurement of state of charge, and (4) stored energy safety issues. Recent advances in ultra-capacitor technology create an opportunity to address these concerns. The NASA Lewis Research Center, in cooperation with industry and academia, has developed an advanced hybrid electric transit bus using ultra-capacitors as the primary energy storage system. At over 15,000-kg gross weight, this is the largest vehicle of its kind ever built using this advanced energy storage technology. Results of analyses show that the vehicle will match the performance of an equivalent conventionally powered vehicle over typical inner city drive cycles. This paper describes the overall power system architecture, the evolution of the control strategy, and analysis of power flow and vehicle performance.

  18. DIMETHYL ETHER (DME)-FUELED SHUTTLE BUS DEMONSTRATION PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Elana M. Chapman; Shirish Bhide; Jennifer Stefanik; Howard Glunt; Andre L. Boehman; Allen Homan; David Klinikowski

    2003-04-01

    The objectives of this research and demonstration program are to convert a campus shuttle bus to operation on dimethyl ether, a potential ultra-clean alternative diesel fuel. To accomplish this objective, this project includes laboratory evaluation of a fuel conversion strategy, as well as, field demonstration of the DME-fueled shuttle bus. Since DME is a fuel with no lubricity (i.e., it does not possess the lubricating quality of diesel fuel), conventional fuel delivery and fuel injection systems are not compatible with dimethyl ether. Therefore, to operate a diesel engine on DME one must develop a fuel-tolerant injection system, or find a way to provide the necessary lubricity to the DME. In this project, they have chosen the latter strategy in order to achieve the objective with minimal need to modify the engine. Their strategy is to blend DME with diesel fuel, to obtain the necessary lubricity to protect the fuel injection system and to achieve low emissions. The bulk of the efforts over the past year were focused on the conversion of the campus shuttle bus. This process, started in August 2001, took until April 2002 to complete. The process culminated in an event to celebrate the launching of the shuttle bus on DME-diesel operation on April 19, 2002. The design of the system on the shuttle bus was patterned after the system developed in the engine laboratory, but also was subjected to a rigorous failure modes effects analysis (FMEA, referred to by Air Products as a ''HAZOP'' analysis) with help from Dr. James Hansel of Air Products. The result of this FMEA was the addition of layers of redundancy and over-pressure protection to the system on the shuttle bus. The system became operational in February 2002. Preliminary emissions tests and basic operation of the shuttle bus took place at the Pennsylvania Transportation Institute's test track facility near the University Park airport. After modification and optimization of the system on

  19. Texas Hydrogen Highway Fuel Cell Hybrid Bus and Fueling Infrastructure Technology Showcase - Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Hitchcock, David

    2012-06-29

    , and regenerative braking for battery charging. It uses a 19.3 kW Ballard PEM fuel cell, will store 12.6 kg of hydrogen at 350 Bar, and includes a 60 kWh battery storage system. The objectives of the project included the following: (a) To advance commercialization of hydrogen-powered transit buses and supporting infrastructure; (b) To provide public outreach and education by showcasing the operation of a 22-foot fuel cell hybrid shuttle bus and Texas first hydrogen fueling infrastructure; and (c) To showcase operation of zero-emissions vehicle for potential transit applications. As mentioned above, the project successfully demonstrated an early vehicle technology, the Ebus plug-in hybrid fuel cell bus, and that success has led to the acquisition of a more advanced vehicle that can take advantage of the same fueling infrastructure. Needed hydrogen station improvements have been identified that will enhance the capabilities of the fueling infrastructure to serve the new bus and to meet the transit agency needs. Over the course of this project, public officials, local government staff, and transit operators were engaged in outreach and education activities that acquainted them with the real world operation of a fuel cell bus and fueling infrastructure. Transit staff members in the Dallas/Ft. Worth region were invited to a workshop in Arlington, Texas at the North Central Texas Council of Governments to participate in a workshop on hydrogen and fuel cells, and to see the fuel cell bus in operation. The bus was trucked to the meeting for this purpose so that participants could see and ride the bus. Austin area transit staff members visited the fueling site in Austin to be briefed on the bus and to participate in a fueling demonstration. This led to further meetings to determine how a fuel cell bus and fueling station could be deployed at Capital Metro Transit. Target urban regions that expressed additional interest during the project in response to the outreach meetings and

  20. 基于R5F2L38A的电动汽车直流电能表设计%DC electric energy meter design for electric car based on R5F2L38A

    Institute of Scientific and Technical Information of China (English)

    彭宇; 朱青; 孙猛

    2012-01-01

    设计了一款专门为电动汽车电池充放电进行准确计量的直流电能表,用来测量其电压、电流、功率和电量.采用高精度的采样计量和高速的MCU进行数据处理,采用非易失存储器进行电量存储,采用远红外和CAN总线进行数据抄读.实际运行结果表明,研发出的电动汽车专用计量直流表具有低成本、低功耗、高稳定性的特点.%This paper designs a specifically for the electriccar battery charging and discharging the accurate measurement of the dc electric energymeter, Used to measure the voltage, current, power and energy. Adopting high precision sa-mpling measurement, high speed data processing of MCU, using non-volatile memory stor-age model, the CAN bus and far infrared data copy read, The actual operation shows that the electric car research and development of special measurement table with low cost, low power consumption, and high stability features.

  1. CROSS-FRONTIER PUBLIC TRANSPORT: Y BUS

    CERN Document Server

    CERN Housing Service

    2002-01-01

    'Y' buses cover the journey between Val Thoiry in France (shopping centre including'Migros' and other stores) and Blandonnet in Switzerland, where they stop outside the 'Jumbo' shop, now renamed 'Carrefour'. In France, the buses connect up Thoiry, Sergy and St. Genis, then cross the border to stop outside CERN, Meyrin, before continuing towards Geneva along the 'Route de Meyrin', stopping outside the 'La Tour' hospital, then at the terminus Blandonnet. The normal fare on French territory with a slight incursion into Switzerland for this purpose as far as CERN, Meyrin, is 1.20 Euros per single journey (ticket valid for one hour). The same amount is charged for any single journey in Switzerland. For example, the cost of a single journey between St. Genis and the 'La Tour' hospital would be 2.40 Euros. The season ticket ('Abonnement de Travail') opens the right to purchase a ticket valid over any period of seven days which entitles the holder to as many journeys as required between the bus stop nearest to the pl...

  2. A Low-Cost Soft-Switched DC/DC Converter for Solid-Oxide Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Jason Lai

    2009-03-03

    A highly efficient DC to DC converter has been developed for low-voltage high-current solid oxide fuel cells. The newly developed 'V6' converter resembles what has been done in internal combustion engine that split into multiple cylinders to increase the output capacity without having to increase individual cell size and to smooth out the torque with interleaving operation. The development was started with topology overview to ensure that all the DC to DC converter circuits were included in the study. Efficiency models for different circuit topologies were established, and computer simulations were performed to determine the best candidate converter circuit. Through design optimization including topology selection, device selection, magnetic component design, thermal design, and digital controller design, a bench prototype rated 5-kW, with 20 to 50V input and 200/400V output was fabricated and tested. Efficiency goal of 97% was proven achievable through hardware experiment. This DC to DC converter was then modified in the later stage to converter 35 to 63 V input and 13.8 V output for automotive charging applications. The complete prototype was tested at Delphi with their solid oxide fuel cell test stand to verify the performance of the modified DC to DC converter. The output was tested up to 3-kW level, and the efficiency exceeded 97.5%. Multiple-phase interleaving operation design was proved to be reliable and ripple free at the output, which is desirable for the battery charging. Overall this is a very successful collaboration project between the SECA Core Technology Team and Industrial Team.

  3. Alkaline battery operational methodology

    Energy Technology Data Exchange (ETDEWEB)

    Sholklapper, Tal; Gallaway, Joshua; Steingart, Daniel; Ingale, Nilesh; Nyce, Michael

    2016-08-16

    Methods of using specific operational charge and discharge parameters to extend the life of alkaline batteries are disclosed. The methods can be used with any commercial primary or secondary alkaline battery, as well as with newer alkaline battery designs, including batteries with flowing electrolyte. The methods include cycling batteries within a narrow operating voltage window, with minimum and maximum cut-off voltages that are set based on battery characteristics and environmental conditions. The narrow voltage window decreases available capacity but allows the batteries to be cycled for hundreds or thousands of times.

  4. Lithium Ion Batteries

    Science.gov (United States)

    1997-01-01

    Lithium ion batteries, which use a new battery chemistry, are being developed under cooperative agreements between Lockheed Martin, Ultralife Battery, and the NASA Lewis Research Center. The unit cells are made in flat (prismatic) shapes that can be connected in series and parallel to achieve desired voltages and capacities. These batteries will soon be marketed to commercial original-equipment manufacturers and thereafter will be available for military and space use. Current NiCd batteries offer about 35 W-hr/kg compared with 110 W-hr/kg for current lithium ion batteries. Our ultimate target for these batteries is 200 W-hr/kg.

  5. New non-linear control strategy for non-isolated DC/DC converter with high voltage ratio

    Energy Technology Data Exchange (ETDEWEB)

    Shahin, A.; Huang, B.; Martin, J.P.; Pierfederici, S.; Davat, B. [Groupe de Recherche en Electronique et en Electrotechnique de Nancy - INPL - Nancy Universite, 2, Avenue de la Foret de Haye, 54516 Vandoeuvre-les-Nancy Cedex (France)

    2010-01-15

    In this paper, a non-isolated DC/DC converter with high voltage ratio is proposed to allow the interface between a low voltage power source like fuel cell and a high voltage DC bus. To take into account the low voltage-high density characteristics of power sources, a cascaded structure composed of two sub-converters has been chosen and allows obtaining a high voltage ratio. The choice of each sub-converter is based on the requirements of the source and its performances. Consequently, we have chosen a three-interleaved boost converter as the 1st sub-converter whereas the 2nd sub-converter is a three-level boost converter. The control of the whole system is realized thanks to energetic trajectories planning based on flatness properties of the system. The control of both the current and the balance of voltage across the output serial capacitors of the three-level boost converter is ensured by non-linear controllers based on a new non-linear model. Experimental results allow validating the proposed power architecture and its associated control. (author)

  6. High Efficiency Non-isolated Three Port DC-DC Converter for PV-Battery Systems

    DEFF Research Database (Denmark)

    Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe;

    2016-01-01

    This paper presents a nonisolated Three Port Converter (TPC) with a unidirectional port for photovoltaic (PV) panels and a bidirectional port for energy storage. With the proposed topology single power conversion is performed between each port, so high efficiencies are obtained. A theoretical ana...

  7. High Efficiency Non-isolated Three Port DC-DC Converter for PV-Battery Systems

    DEFF Research Database (Denmark)

    Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe;

    2016-01-01

    This paper presents a nonisolated Three Port Converter (TPC) with a unidirectional port for photovoltaic (PV) panels and a bidirectional port for energy storage. With the proposed topology single power conversion is performed between each port, so high efficiencies are obtained. A theoretical...

  8. Modular Approach for Continuous Cell-Level Balancing to Improve Performance of Large Battery Packs: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Muneed ur Rehman, M.; Evzelman, M.; Hathaway, K.; Zane, R.; Plett, G. L.; Smith, K.; Wood, E.; Maksimovic, D.

    2014-10-01

    Energy storage systems require battery cell balancing circuits to avoid divergence of cell state of charge (SOC). A modular approach based on distributed continuous cell-level control is presented that extends the balancing function to higher level pack performance objectives such as improving power capability and increasing pack lifetime. This is achieved by adding DC-DC converters in parallel with cells and using state estimation and control to autonomously bias individual cell SOC and SOC range, forcing healthier cells to be cycled deeper than weaker cells. The result is a pack with improved degradation characteristics and extended lifetime. The modular architecture and control concepts are developed and hardware results are demonstrated for a 91.2-Wh battery pack consisting of four series Li-ion battery cells and four dual active bridge (DAB) bypass DC-DC converters.

  9. DC Smart Grid Connected with Fuel Charging Station and AC Load by Hybrid MLI

    Directory of Open Access Journals (Sweden)

    Naveen Kumar

    2013-07-01

    Full Text Available This paper presents the Solar (photo voltaic power Plant and Windmill plant with DC Smart Grid connected with an DC Fuel Charging Station For Electric Vehicle (EV, Plug in Hybrid Electric Vehicle (PHEV and converted to AC load for Consumer single or Three phase ac load by means of Hybrid Multilevel Inverter (MLI. Solar Energy which store energy in lithium-ion battery and connected to Smart Grid .Wind Energy which get stored in Lithium-ion battery that Fixed DC Voltage connected with DC Smart Grid. Smart Grid which are Connected with DC Fuel Charging Station in Ring Topology with a certain distance for charging of Electric Vehicle (EV and Plug-in Hybrid Electric Vehicle with On-Board (Integrated Charger for faster charging of EV. In Power demand for Consumer the DC load from smart grid converted into an ac load by Hybrid Multilevel Inverter. In Consumers Place the small wind mill and PV panel are installed that energy can be used for consumers load at peak time or power Shutdown .Other than the power shutdown or peak time in the consumers place, stored DC Energy can be fed to Smart Grid. A major development in distribution automation is deployment of smart meters as a gateway between the utility and customer. With such capabilities the smart meter becomes not only a point of measurement of consumed kWh but also a controller capable of bidirectional communications with both the customer and utility.

  10. Application of CAN Bus Technology on Zhongtong Bus%CAN总线技术在中通客车上的应用

    Institute of Scientific and Technical Information of China (English)

    赵佳

    2012-01-01

    The application status of CAN bus technology on Zhongtong bus is introduced, the methods of bus data collection and analysis on Zhongtong traditional and new energy bus are discussed and the development direction of CAN bus technology is prospected.%介绍CAN总线技术在中通客车上的应用状况,探讨中通传统客车及新能源客车的总线数据采集和分析方法。

  11. Voltage Scheduling Droop Control for State-of-Charge Balance of Distributed Energy Storage in DC Microgrids

    DEFF Research Database (Denmark)

    Li, Chendan; Dragicevic, Tomislav; Aldana, Nelson Leonardo Diaz;

    2014-01-01

    the State-of-Charge balance. In this paper, a new droop method based on voltage scheduling for State-of-Charge balance is proposed to keep the SoC balance for the energy storage units. The proposed method has the advantage of avoiding the stability problem existed in traditional methods based on droop gain...... scheduling. Simulation experiment is taken in Matlab on a DC microgrid with two distributed energy storage units. The simulation results show that the proposed method has successfully achieved SoC balance during the load changes while maintaining the DC bus voltage within the allowable range....

  12. Texas Hydrogen Highway Fuel Cell Hybrid Bus and Fueling Infrastructure Technology Showcase - Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Hitchcock, David

    2012-06-29

    , and regenerative braking for battery charging. It uses a 19.3 kW Ballard PEM fuel cell, will store 12.6 kg of hydrogen at 350 Bar, and includes a 60 kWh battery storage system. The objectives of the project included the following: (a) To advance commercialization of hydrogen-powered transit buses and supporting infrastructure; (b) To provide public outreach and education by showcasing the operation of a 22-foot fuel cell hybrid shuttle bus and Texas first hydrogen fueling infrastructure; and (c) To showcase operation of zero-emissions vehicle for potential transit applications. As mentioned above, the project successfully demonstrated an early vehicle technology, the Ebus plug-in hybrid fuel cell bus, and that success has led to the acquisition of a more advanced vehicle that can take advantage of the same fueling infrastructure. Needed hydrogen station improvements have been identified that will enhance the capabilities of the fueling infrastructure to serve the new bus and to meet the transit agency needs. Over the course of this project, public officials, local government staff, and transit operators were engaged in outreach and education activities that acquainted them with the real world operation of a fuel cell bus and fueling infrastructure. Transit staff members in the Dallas/Ft. Worth region were invited to a workshop in Arlington, Texas at the North Central Texas Council of Governments to participate in a workshop on hydrogen and fuel cells, and to see the fuel cell bus in operation. The bus was trucked to the meeting for this purpose so that participants could see and ride the bus. Austin area transit staff members visited the fueling site in Austin to be briefed on the bus and to participate in a fueling demonstration. This led to further meetings to determine how a fuel cell bus and fueling station could be deployed at Capital Metro Transit. Target urban regions that expressed additional interest during the project in response to the outreach meetings and

  13. Development of HFF6120G03SHEV Plug-in Hybrid Electric Bus%HFF6120G03SHEV插电式混合动力客车开发

    Institute of Scientific and Technical Information of China (English)

    王少凯

    2015-01-01

    简要介绍HFF6120G03SHEV插电式混合动力客车整车的开发和驱动控制系统的设计,以及整车动力电池组布置技术方案.%The author briefly introduces the whole vehicle development, drive control system design and the vehicle power battery layout scheme of HFF6120G03SHEV plug-in hybrid electric bus.

  14. On and off controlled resonant dc-dc power converter

    DEFF Research Database (Denmark)

    2015-01-01

    output voltage and connection to a converter load. The resonant DC-DC power converter further comprises a rectification circuit connected between an output of a resonant network and the output side circuit. The resonant network is configured for alternatingly being charged from the input voltage...... or current and discharged through the rectification circuit by a first controllable switch arrangement in accordance with a first switch control signal. A second controllable switch arrangement of the resonant DC-DC power converter is configured to select a first impedance characteristic of the resonant...

  15. Step-Up DC-DC Power Converter

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a step-up DC-DC power converter which comprises a primary side circuit and a secondary side circuit coupled through a galvanic isolation barrier. The primary side circuit comprises a positive and a negative input terminal for receipt of an input voltage and an input...... being charged from the input voltage and discharged to the output capacitor through the galvanic isolation barrier in accordance with a switch control signal to produce the converter output voltage. The step-up DC-DC power converter comprises an electrical short-circuit connection across the galvanic...

  16. A Novel FPSM Controller for DC-DC Switching Converters

    Institute of Scientific and Technical Information of China (English)

    Yong Feng; Shun-Ping Wang; Ping Luo; Quan-Ming Niu; Zhao-Ji Li

    2007-01-01

    This paper presents a novel fuzzy pulse skip modulation (FPSM) controller for switching direct current to direct current (DC-DC) converters based on fuzzy ratiocination modeling approach. Owing to the optimal consideration during the design and the nonlinear characteristics of the controller, improved dynamic responses of the FPSM controller can be achieved over conventional controllers. Compared with conventional proportion integral derivative (PID) control, FPSM control has 60% lower overshoot and 10% lower setting time under the same input voltage and output load change. The presented approach is general and can be applied to other types of DC-DC converters.

  17. High performance dc-dc conversion with voltage multipliers

    Science.gov (United States)

    Harrigill, W. T.; Myers, I. T.

    1974-01-01

    The voltage multipliers using capacitors and diodes first developed by Cockcroft and Walton in 1932 were reexamined in terms of state of the art fast switching transistors and diodes, and high energy density capacitors. Because of component improvements, the voltage multiplier, used without a transformer, now appears superior in weight to systems now in use for dc-dc conversion. An experimental 100-watt 1000-volt dc-dc converter operating at 100 kHz was built, with a component weight of about 1 kg/kW. Calculated and measured values of output voltage and efficiency agreed within experimental error.

  18. An Intelligent Power Controller for Hybrid DC Micro Grid Power System

    DEFF Research Database (Denmark)

    Hajizadeh, Amin; Norum, Lars; Hassanzadeh, Fattah;

    2016-01-01

    In this paper, an intelligent power management strategy is proposed for hybrid DC microgrid, including wind turbine, fuel cell and battery energy storage. The considered wind turbine has a permanent magnet synchronous generator (PMSG). In the considered structure, wind turbine operates as the main...

  19. Six-Phase Vehicular Drive with Renewable DC Sources and Hybrid PWM Control of Four Inverters

    DEFF Research Database (Denmark)

    Oleschuk, Valentin; Ermuratskii, Vladimir; Blaabjerg, Frede

    2015-01-01

    The paper presents results of research of quad-inverter-based automotive system with combined scheme of PWM control of inverters, supplied by two renewable dc sources (by fuel cells and by battery). It has been shown, that hybrid switching techniques can be used successfully for control of vehicle...

  20. Improved DC Gun Insulator

    Energy Technology Data Exchange (ETDEWEB)

    M.L. Neubauer, K.B. Beard, R. Sah, C. Hernandez-Garcia, G. Neil

    2009-05-01

    Many user facilities such as synchrotron light sources and free electron lasers require accelerating structures that support electric fields of 10-100 MV/m, especially at the start of the accelerator chain where ceramic insulators are used for very high gradient DC guns. These insulators are difficult to manufacture, require long commissioning times, and have poor reliability, in part because energetic electrons bury themselves in the ceramic, creating a buildup of charge and causing eventual puncture. A novel ceramic manufacturing process is proposed. It will incorporate bulk resistivity in the region where it is needed to bleed off accumulated charge caused by highly energetic electrons. This process will be optimized to provide an appropriate gradient in bulk resistivity from the vacuum side to the air side of the HV standoff ceramic cylinder. A computer model will be used to determine the optimum cylinder dimensions and required resistivity gradient for an example RF gun application. A ceramic material example with resistivity gradient appropriate for use as a DC gun insulator will be fabricated by glazing using doping compounds and tested.

  1. Car Delay Model near Bus Stops with Mixed Traffic Flow

    Directory of Open Access Journals (Sweden)

    Yang Xiaobao

    2013-01-01

    Full Text Available This paper proposes a model for estimating car delays at bus stops under mixed traffic using probability theory and queuing theory. The roadway is divided to serve motorized and nonmotorized traffic streams. Bus stops are located on the nonmotorized lanes. When buses dwell at the stop, they block the bicycles. Thus, two conflict points between car stream and other traffic stream are identified. The first conflict point occurs as bicycles merge to the motorized lane to avoid waiting behind the stopping buses. The second occurs as buses merge back to the motorized lane. The average car delay is estimated as the sum of the average delay at these two conflict points and the delay resulting from following the slower bicycles that merged into the motorized lane. Data are collected to calibrate and validate the developed model from one site in Beijing. The sensitivity of car delay to various operation conditions is examined. The results show that both bus stream and bicycle stream have significant effects on car delay. At bus volumes above 200 vehicles per hour, the curbside stop design is not appropriate because of the long car delays. It can be replaced by the bus bay design.

  2. Capacity Region of a New Bus Communication Model

    Directory of Open Access Journals (Sweden)

    Zhuojun Zhuang

    2013-02-01

    Full Text Available In this paper, we study a new bus communication model, where two transmitters wish to send their corresponding private messages and a common message to a destination, while they also wish to send the common message to another receiver connected to the same wire. From an information-theoretical point of view, we first study a general case of this new model (with discrete memoryless channels. The capacity region composed of all achievable (R0,R1,R2 triples is determined for this general model, where R1 and R2 are the transmission rates of the private messages and R0 is the transmission rate of the common message. Then, the result is further explained via the Gaussian example. Finally, we give the capacity region for the new bus communication model with additive Gaussian noises and attenuation factors. This new bus communication model captures various communication scenarios, such as the bus systems in vehicles, and the bus type of communication channel in power line communication (PLC networks.

  3. Combined operation of AC and DC distribution system with distributed generation units

    International Nuclear Information System (INIS)

    This paper presents a DC distribution system which has been supplied by external AC systems as well as local DG units in order to demonstrate an overall solution to power quality issue. In this paper, the proposed operation method is demonstrated by simulation of power transfer between external AC systems, DG units, AC and DC loads. The power flow control in DC distribution system has been achieved by network converters and DG converters. Also, the mathematical model of the network, DG and load converters are obtained by using the average technique, which allows converter systems accurately simulated and control strategies for this converters is achieved. A suitable control strategy for network converters has been proposed that involves DC voltage droop regulator and novel instantaneous power regulation scheme. Also, a novel control technique has been proposed for DG converters. In this paper, a novel control system based on stationary and synchronously rotating reference frame has been proposed for load converters for supplying AC loads connected to the DC bus by balanced voltages. The several case studies have been studied based on proposed methods. The simulation results show that DC distribution systems including DG units can improve the power quality at the point of common coupling (PCC) in the power distribution system or industrial power system. (authors)

  4. Coordination Control Strategy for AC/DC Hybrid Microgrids in Stand-Alone Mode

    Directory of Open Access Journals (Sweden)

    Dwi Riana Aryani

    2016-06-01

    Full Text Available Interest in DC microgrids is rapidly increasing along with the improvement of DC power technology because of its advantages. To support the integration process of DC microgrids with the existing AC utility grids, the form of hybrid AC/DC microgrids is considered for higher power conversion efficiency, lower component cost and better power quality. In the system, AC and DC portions are connected through interlink bidirectional AC/DC converters (IC with a proper control system and power management. In the stand-alone operation mode of AC/DC hybrid microgrids, the control of power injection through the IC is crucial in order to maintain the system security. This paper mainly deals with a coordination control strategy of IC and a battery energy storage system (BESS converter under stand-alone operation. A coordinated control strategy for the IC, which considers the state of charge (SOC level of BESS and the load shedding scheme as the last resort, is proposed to obtain better power sharing between AC and DC subgrids. The scheme will be tested with a hybrid AC/DC microgrid, using the tool of the PSCAD/EMTDC software.

  5. Contagion processes on urban bus networks in Indian cities

    CERN Document Server

    Chatterjee, Atanu; Jagannathan, Krishna

    2015-01-01

    Bus transportation is considered as one of the most convenient and cheapest modes of public transportation in Indian cities. Due to their cost-effectiveness and wide reachability, they help a significant portion of the human population in cities to reach their destinations every day. Although from a transportation point of view they have numerous advantages over other modes of public transportation, they also pose a serious threat of contagious diseases spreading throughout the city. The presence of numerous local spatial constraints makes the process and extent of epidemic spreading extremely difficult to predict. Also, majority of the studies have focused on the contagion processes on scale-free network topologies whereas, spatially-constrained real-world networks such as, bus networks exhibit a wide-spectrum of network topology. Therefore, we aim in this study to understand this complex dynamical process of epidemic outbreak and information diffusion on the bus networks for six different Indian cities usin...

  6. Optimal Locations of Bus Stops Connecting Subways near Urban Intersections

    Directory of Open Access Journals (Sweden)

    Yuan Cui

    2015-01-01

    Full Text Available Unsuitable locations of bus stops which provide feeder transportation connecting subways near urban intersections usually lead to the low efficiency of public transport and level of passenger service. A multiobjective optimization model to distribute such stop locations is proposed to attain the shortest total walk distance of passengers and minimum delay time of cars through intersections and travel time of buses. The Pareto frontier and optimal solutions for the proposed model are given by the distance-based and enumerative methods. The Xizhimen bus stop is selected to implement case studies for verifying the validity of the proposed model. The analysis of sensitivity on possible solutions is also carried out in the case studies. The results show that the proposed model is capable of optimizing the locations of bus stops connecting subways near intersections and helpful to improve the level of passengers service and operational efficiency of public transportation.

  7. American Fuel Cell Bus Project Evaluation. Second Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, Leslie [National Renewable Energy Lab. (NREL), Golden, CO (United States); Post, Matthew [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-09-01

    This report presents results of the American Fuel Cell Bus (AFCB) Project, a demonstration of fuel cell electric buses operating in the Coachella Valley area of California. The prototype AFCB was developed as part of the Federal Transit Administration's (FTA's) National Fuel Cell Bus Program. Through the non-profit consortia CALSTART, a team led by SunLine Transit Agency and BAE Systems developed a new fuel cell electric bus for demonstration. SunLine added two more AFCBs to its fleet in 2014 and another in 2015. FTA and the AFCB project team are collaborating with the U.S. Department of Energy (DOE) and DOE's National Renewable Energy Laboratory to evaluate the buses in revenue service. This report summarizes the performance results for the buses through June 2015.

  8. MPP-Tracking DC-DC converters in Photovoltaic applications. Implementation, modeling and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Leppaeaho, J.

    2011-07-01

    This thesis provides a comprehensive study of switched-mode dc-dc converters in terms of dynamic characterization, implementation and operational constraints. The study concentrates on the maximum-power-point-tracking converters used in photovoltaic interfacing in order to maximize the power generation. The main objective is to emphasize the differences between the four basic conversion schemes and to analyze the dynamical characteristics of the current-fed converters. Harvesting of solar energy directly into electrical energy is known to be challenging due to the highly varying terminal characteristics of the energy harvesting unit, i.e., generally a photovoltaic generator. The environmental conditions as well as the load determine its characteristics. The operation point of PV generator has to be kept at its maximum-power point in order to maximize the harvested energy. The dc-dc switched-mode converters are conventionally used to interface the energy sources possessing constant-voltage behavior such as batteries or voltage buses but the same converters are also used as a basis for the maximum-power-point-tracking devices. It is observed, however, that such voltage-fed converters are not capable of interfacing a photovoltaic generator optimally because of its current-source nature. Therefore, an additional capacitor is usually added between the source and converter to enhance the constant-voltage properties of the source and to enable the input-voltage-based feedback control. It is known that the dual nature of PV generator enables the use of either input-voltage or input-current feedback control. It is observed, that the input-current control is prone to saturation of the controller and therefore, the input-voltage control is recommended to be used. The use of input-voltage control will, however, force the converter operate as a current-fed converter causing also significant changes to its static and dynamic properties as well as constraints related to the

  9. Enhancement of Voltage Stability of DC Smart Grid During Islanded Mode by Load Shedding Scheme

    Science.gov (United States)

    Nassor, Thabit Salim; Senjyu, Tomonobu; Yona, Atsushi

    2015-10-01

    This paper presents the voltage stability of a DC smart grid based on renewable energy resources during grid connected and isolated modes. During the islanded mode the load shedding, based on the state of charge of the battery and distribution line voltage, was proposed for voltage stability and reservation of critical load power. The analyzed power system comprises a wind turbine, a photovoltaic generator, storage battery as controllable load, DC loads, and power converters. A fuzzy logic control strategy was applied for power consumption control of controllable loads and the grid-connected dual active bridge series resonant converters. The proposed DC Smart Grid operation has been verified by simulation using MATLAB® and PLECS® Blockset. The obtained results show the effectiveness of the proposed method.

  10. Very High Frequency Half Bridge DC/DC Converter

    DEFF Research Database (Denmark)

    Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.

    2014-01-01

    This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all...

  11. A Plasma-Based DC-DC Electrical Transformer

    Science.gov (United States)

    Nebel, Richard; Finn, John

    2013-10-01

    Previous work has indicated that it may be possible to make DC-DC electrical transformers using plasmas. The mechanism is an MHD electromagnetic relaxation process induced by helical electrodes. This process is now being tested on the Bismark device at Tibbar Technologies.

  12. Power flow analysis for DC voltage droop controlled DC microgrids

    DEFF Research Database (Denmark)

    Li, Chendan; Chaudhary, Sanjay; Dragicevic, Tomislav;

    2014-01-01

    This paper proposes a new algorithm for power flow analysis in droop controlled DC microgrids. By considering the droop control in the power flow analysis for the DC microgrid, when compared with traditional methods, more accurate analysis results can be obtained. The algorithm verification is ca...

  13. Dc-To-Dc Converter Uses Reverse Conduction Of MOSFET's

    Science.gov (United States)

    Gruber, Robert P.; Gott, Robert W.

    1991-01-01

    In modified high-power, phase-controlled, full-bridge, pulse-width-modulated dc-to-dc converters, switching devices power metal oxide/semiconductor field-effect transistors (MOSFET's). Decreases dissipation of power during switching by eliminating approximately 0.7-V forward voltage drop in anti-parallel diodes. Energy-conversion efficiency increased.

  14. A High-Efficiency Grid-Tie Battery Energy Storage System

    OpenAIRE

    Qian, Hao

    2011-01-01

    Lithium-ion based battery energy storage system has become one of the most popular forms of energy storage system for its high charge and discharge efficiency and high energy density. This dissertation proposes a high-efficiency grid-tie lithium-ion battery based energy storage system, which consists of a LiFePO4 battery based energy storage and associated battery management system (BMS), a high-efficiency bidirectional ac-dc converter and the central control unit which controls the operation...

  15. Evaluation of different methods for measuring the impedance of Lithium-ion batteries during ageing

    DEFF Research Database (Denmark)

    Stroe, Daniel Loan; Swierczynski, Maciej Jozef; Stroe, Ana-Irina;

    2015-01-01

    are presented for measuring the impedance of Lithium-ion batteries and electrochemical impedance spectroscopy and dc current pulses are the most used ones; each of these approaches has its own advantages and drawbacks. The goal of this paper is to investigate which of the most encountered impedance measurement......The impedance represents one of the most important performance parameters of the Lithium-ion batteries since it used for power capability calculations, battery pack and system design, cooling system design and also for state-of-health estimation. In the literature, different approaches...... approaches is the most suitable for measuring the impedance of Lithium-ion batteries during ageing....

  16. A DC Transformer

    Science.gov (United States)

    Youngquist, Robert C.; Ihlefeld, Curtis M.; Starr, Stanley O.

    2013-01-01

    A component level dc transformer is described in which no alternating currents or voltages are present. It operates by combining features of a homopolar motor and a homopolar generator, both de devices, such that the output voltage of a de power supply can be stepped up (or down) with a corresponding step down (or up) in current. The basic theory for this device is developed, performance predictions are made, and the results from a small prototype are presented. Based on demonstrated technology in the literature, this de transformer should be scalable to low megawatt levels, but it is more suited to high current than high voltage applications. Significant development would be required before it could achieve the kilovolt levels needed for de power transmission.

  17. CA6127URE31纯电动客车总体设计%Overall Design of CA6127URE31 Pure Electric Bus

    Institute of Scientific and Technical Information of China (English)

    刘力楠; 孙红; 黄俊杰

    2013-01-01

    The authors briefly introduce the whole vehicle technical parameters, the pure electric system technical plan, the interior decoration technical scheme and the vehicle power battery layout technical scheme of CA6127URE31 pure electric bus.%简要介绍CA6127URE31纯电动客车的整车技术参数、纯电动系统的技术方案、内饰技术方案以及整车动力电池组布置技术方案。

  18. Distributed cooperative synchronization strategy for multi-bus microgrids

    DEFF Research Database (Denmark)

    Sun, Yao; Zhong, Chaolu; Hou, Xiaochao;

    2017-01-01

    synchronization methods based on centralized communication are very costly and not suitable for multi-bus microgrids that have a large number of distributed generators (DGs). To address this concern, this study presents an active synchronization control strategy based on distributed cooperation technology...... for multi-bus microgrids. The proposed method can reconnect the microgrid in island to UG seamlessly with sparse communication channels. Synchronization correction signals are generated by a voltage controller, which are only transmitted to the leader DGs. Meanwhile, each DG exchanges information with its...

  19. Black silicon with black bus-bar strings

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Tang, Peter Torben; Mizushima, Io;

    2016-01-01

    We present the combination of black silicon texturing and blackened bus-bar strings as a potential method for obtaining all-black solar panels, while using conventional, front-contacted solar cells. Black silicon was realized by mask-less reactive ion etching resulting in total, average reflectance...... below 0.5% across a 156x156 mm2 silicon wafer. Black bus-bars were realized by oxidized copper resulting in reflectance below 3% in the entire visible wavelength range. The combination of these two technologies may result in aesthetic, all-black panels based on conventional, front-contacted solar cells...

  20. Persecution as a Theme in Isaac Bashevis Singer's The Bus

    Institute of Scientific and Technical Information of China (English)

    Wu Minzhi

    2008-01-01

    Isaac Bashevis Singer is very much concerned about the fate of Jewish people,so he often presents Jews'sufferings in his literary works.The Bus,by means of describing the narrator's experiences during a bus tour through Spain,in different dimensions reinforces the destructive impact of persecution that Jews have gone through.Moreover,he implies such persecution is not merely confined between Jews and the Gentile,but also spreads among the whole human beings who hold differet beliefs.

  1. Improving student bus-riding behavior through a whole-school intervention.

    OpenAIRE

    Putnam, Robert F; Handler, Marcie W; Ramirez-Platt, Christina M; Luiselli, James K

    2003-01-01

    We describe a multicomponent intervention to improve bus-riding behavior of students attending an urban public school. The intervention was developed with technical assistance consultation that emphasized collaboration among students, school personnel, and bus drivers. The primary intervention procedures were identifying appropriate behaviors during transportation ("bus rules"), training bus drivers to deliver positive reinforcement, and rewarding student performance through a weekly school-b...

  2. Bus Catcher: A Context Sensitive Prototype System for Public Transportation Users

    OpenAIRE

    Bertolotto, Michela; O'Hare, G.M.P.; Strahan, Robin; Brophy, Ailish; Martin, A.; McLoughlin, Eoin

    2002-01-01

    In this paper we describe the architectural and functional characteristics of Bus Catcher, a context sensitive prototype system for public transportation users. Bus Catcher assists mobile users in planning their bus rides by providing timely and accurate information about current bus locations and estimated arrival times. A complete report on the implementation together with a preliminary evaluation of the system is provided in this paper.

  3. Performance evaluation of UHF RFID technologies for real-time bus recognition in the Taipei Bus Station.

    Science.gov (United States)

    Own, Chung-Ming; Lee, Da-Sheng; Wang, Ti-Ho; Wang, De-Jun; Ting, Yu-Lun

    2013-06-18

    Transport stations such as airports, ports, and railways have adopted blocked-type pathway management to process and control travel systems in a one-directional manner. However, this excludes highway transportation where large buses have great variability and mobility; thus, an instant influx of numerous buses increases risks and complicates station management. Focusing on Taipei Bus Station, this study employed RFID technology to develop a system platform integrated with modern information technology that has numerous characteristics. This modern information technology comprised the following systems: ultra-high frequency (UHF) radio-frequency identification (RFID), ultrasound and license number identification, and backstage graphic controls. In conclusion, the system enabled management, bus companies, and passengers to experience the national bus station's new generation technology, which provides diverse information and synchronization functions. Furthermore, this technology reached a new milestone in the energy-saving and efficiency-increasing performance of Taiwan's buses.

  4. Design of high efficiency dual-mode buck DC-DC converter

    Science.gov (United States)

    Xinquan, Lai; Huali, Zeng; Qiang, Ye; Huisen, He; Shasha, Zhang; Yuqing, Sun

    2010-11-01

    A buck DC—DC switching regulator with high efficiency is implemented by automatically altering the modulation mode according to load current, and it can operate with an input range of 4.5 to 30 V. At light load current, the converter operates in skip mode. The converter enters PWM mode operation with increasing load current. It reduces the switching loss at light load and standby state, which results in prolonging battery lifetime and stand-by time. Meanwhile, externally adjustable soft-start minimizes the inrush supply current and avoids the overshoot of output voltage at initial startup. The regulator is fabricated by a 0.6 μm CDMOS process. The test results show that, under the condition of 3.3 V output, the efficiency is up to 64% at 5 mA and the maximum efficiency is 95.5%.

  5. Rechargeable batteries applications handbook

    CERN Document Server

    1998-01-01

    Represents the first widely available compendium of the information needed by those design professionals responsible for using rechargeable batteries. This handbook introduces the most common forms of rechargeable batteries, including their history, the basic chemistry that governs their operation, and common design approaches. The introduction also exposes reader to common battery design terms and concepts.Two sections of the handbook provide performance information on two principal types of rechargeable batteries commonly found in consumer and industrial products: sealed nickel-cad

  6. Battery systems engineering

    CERN Document Server

    Rahn, Christopher D

    2012-01-01

    A complete all-in-one reference on the important interdisciplinary topic of Battery Systems Engineering Focusing on the interdisciplinary area of battery systems engineering, this book provides the background, models, solution techniques, and systems theory that are necessary for the development of advanced battery management systems. It covers the topic from the perspective of basic electrochemistry as well as systems engineering topics and provides a basis for battery modeling for system engineering of electric and hybrid electric vehicle platforms. This original

  7. Battery Review Board

    Science.gov (United States)

    Vaughn, Chester

    1993-01-01

    The topics covered are presented in viewgraph form: NASA Battery Review Board Charter; membership, board chronology; background; statement of problem; summary of problems with 50 AH standard Ni-Cd; activities for near term programs utilizing conventional Ni-Cd; present projects scheduled to use NASA standard Ni-Cd; other near-term NASA programs requiring secondary batteries; recommended direction for future programs; future cell/battery procurement strategy; and the NASA Battery Program.

  8. MSCT findings in a controlled bus bombing using a pig model

    DEFF Research Database (Denmark)

    Hansen, Nikolaj Friis

    2009-01-01

    pig's position in the bus at the time of detonation. 1 of the pigs was rigged as a suicide bomber while the others were individually placed as passengers and bus driver inside the bus alongside dummies. Measurements of the blast force and fast speed video recordings were made during the detonation...

  9. 49 CFR 571.221 - Standard No. 221; School bus body joint strength.

    Science.gov (United States)

    2010-10-01

    ... means any part of the bus, of either a mechanical or electrical nature, which is explicitly identified... 49 Transportation 6 2010-10-01 2010-10-01 false Standard No. 221; School bus body joint strength... STANDARDS Federal Motor Vehicle Safety Standards § 571.221 Standard No. 221; School bus body joint...

  10. 46 CFR 112.05-3 - Main-emergency bus-tie.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Main-emergency bus-tie. 112.05-3 Section 112.05-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS General § 112.05-3 Main-emergency bus-tie. Each bus-tie between a main...

  11. Electric Vehicle Battery Challenge

    Science.gov (United States)

    Roman, Harry T.

    2014-01-01

    A serious drawback to electric vehicles [batteries only] is the idle time needed to recharge their batteries. In this challenge, students can develop ideas and concepts for battery change-out at automotive service stations. Such a capability would extend the range of electric vehicles.

  12. Distributed Consensus-Based Control of Multiple DC-Microgrids Clusters

    DEFF Research Database (Denmark)

    Shafiee, Qobad; Dragicevic, Tomislav; Andrade, Fabio;

    2014-01-01

    This paper presents consensus-based distributed control strategies for voltage regulation and power flow control of dc microgrid (MG) clusters. In the proposed strategy, primary level of control is used to regulate the common bus voltage inside each MG locally. An SOC-based adaptive droop method ......-based cooperative algorithm is employed at this stage to define appropriate reference for power flow between MGs according to their local SOCs. The effectiveness of proposed control scheme is verified through detailed hardware-in-the-loop (HIL) simulations....

  13. Experimental Study on a Passive Fuel Cell/Battery Hybrid Power System

    Directory of Open Access Journals (Sweden)

    Yong-Song Chen

    2013-12-01

    Full Text Available A laboratory-scale passive hybrid power system for transportation applications is constructed and tested in this study. The hybrid power system consists of a fuel cell stack connected with a diode, a lithium-ion battery pack connected with a DC/DC power converter and another diode. The power converter is employed to regulate the output voltage of the battery pack. The dynamic responses of current and voltage of the stack to the start-up and acceleration of the load are experimentally investigated at two different selected output voltages of the DC/DC converter in the battery line. The power sharing of each power source and efficiency are also analyzed and discussed. Experimental results show that the battery can compensate for the shortage of supplied power for the load demand during the start-up and acceleration. The lowest operating voltage of the fuel cell stack is limited by the regulated output voltage of the DC/DC converter. The major power loss in the hybrid power system is attributed to the diodes. The power train efficiency can be improved by lowering the ratio of forward voltage drop of the diode to the operating voltage of the fuel cell stack.

  14. Very-low-frequency and low-frequency electric and magnetic fields associated with electric shuttle bus wireless charging.

    Science.gov (United States)

    Tell, R A; Kavet, Robert; Bailey, J R; Halliwell, John

    2014-01-01

    Tests conducted to date at the University of Tennessee at Chattanooga (UTC) indicate that wireless charging of the Chattanooga Area Regional Transportation Authority's (CARTA) downtown shuttle bus, currently operating with off-board battery charging technology, offers significant improvements in performance and cost. The system operates at a frequency of 20 kHz and a peak power of 60 kW. Because the system's wireless charging is expected to occur during a nominal 3-min charging period with passengers on-board, the magnetic and electric fields associated with charging were characterised at UTC's Advanced Vehicle Test Facility and compared with established human exposure limits. The two most prominent exposure limits are those published by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the Institute for Electrical and Electronic Engineers (IEEE). Both organisations include limits for groups who are trained (workers in specific industries) to be aware of electromagnetic environments and their potential hazards, as well as a lower set of limits for the general public, who are assumed to lack such awareness. None of the magnetic or electric fields measured either within or outside the bus during charging exceeded either the ICNIRP or the IEEE exposure limits for the general public.

  15. Modular Power System Configured with Standard Product Hybrid DC-DC Converters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — VPT proposes an innovative concept whereby complex, multiple-output, DC-DC converter systems can be configured through use of only 2 standard product hybrid DC-DC...

  16. Fuel Cell/Battery Powered Bus System. Final Report for period August 1987 - December 31, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Wimmer, R.

    1999-01-01

    Today, fuel cell systems are getting much attention from the automotive industry as a future replacement for the internal combustion engine (ICE). Every US automobile manufacturer and most foreign firms have major programs underway to develop fuel cell engines for transportation. The objective of this program was to investigate the feasibility of using fuel cells as an alternative to the ICE. Three such vehicles (30-foot buses) were introduced beginning in 1994. Extensive development and operational testing of fuel cell systems as a vehicle power source has been accomplished under this program. The development activity investigated total systems configuration and effectiveness for vehicle operations. Operational testing included vehicle performance testing, road operations, and extensive dynamometer emissions testing.

  17. How to Cut Costs by Saving School Bus Fuel.

    Science.gov (United States)

    Seiff, Hank

    A program started in Washington County, Maryland in 1980 has been successful in saving school bus fuel and bringing down transportation costs incurred by its fleet of 200 buses. Driver training and motivation, as well as a partial transfer to diesel buses, are at the heart of the program. The drivers are taught five fuel saving techniques: cut…

  18. Bullying on the School Bus: A Video Analysis

    Science.gov (United States)

    Raskauskas, Juliana

    2005-01-01

    The purpose of this study was to assess the nature of bullying on the school bus. Videotapes were used to identify occurrences of bullying on buses of elementary school students. Incidents were reviewed for forms of bullying, fullness, presence of friends, and severity of acts. Results indicated that approximately two incidents occurred per bus…

  19. Bussikontsern Go Bus ihaldab Harjumaa turgu / Signe Kalberg

    Index Scriptorium Estoniae

    Kalberg, Signe, 1959-

    2005-01-01

    AS-i Tarbus ja kaheksa bussiettevõtte ühinemisel moodustati AS Go Bus, ettevõte plaanib veel mitme bussifirma liitmist. Atko Grupi juhatuse esimehe Margo Tomingase, AS Sebe nõukogu esimehe Hugo Osula arvamus. Lisa: Konkurentsiamet hoiab silma peal

  20. What's Happening on the School Bus Performance Front?

    Science.gov (United States)

    Combs, Hanford L.

    The most urgent order of business in the national scene is to complete the development of a series of new performance tests for school bus bodies and chassis to establish a benchmark for safe construction that can be verified by independent testing agencies. Such performance tests should incorporate the new Federal Joint Strength Efficiency…

  1. High-Tech School Bus Teaches Students on the Road

    Science.gov (United States)

    Katims, Lauren

    2011-01-01

    Last year, kindergarten through high school students in the rural Hector, Arkansas, School District barely had the technology resources that keep kids interested in math and science. This year, they potentially have the most advanced resources in the country--before they even step into the classroom. One school bus in Arkansas' Pope County has…

  2. A Novel Time Synchronization Method for Dynamic Reconfigurable Bus

    Directory of Open Access Journals (Sweden)

    Zhang Weigong

    2016-01-01

    Full Text Available UM-BUS is a novel dynamically reconfigurable high-speed serial bus for embedded systems. It can achieve fault tolerance by detecting the channel status in real time and reconfigure dynamically at run-time. The bus supports direct interconnections between up to eight master nodes and multiple slave nodes. In order to solve the time synchronization problem among master nodes, this paper proposes a novel time synchronization method, which can meet the requirement of time precision in UM-BUS. In this proposed method, time is firstly broadcasted through time broadcast packets. Then, the transmission delay and time deviations via three handshakes during link self-checking and channel detection can be worked out referring to the IEEE 1588 protocol. Thereby, each node calibrates its own time according to the broadcasted time. The proposed method has been proved to meet the requirement of real-time time synchronization. The experimental results show that the synchronous precision can achieve a bias less than 20 ns.

  3. Platform Screen Doors Enhanced Bus Rapid Transit Intelligent Performance

    Directory of Open Access Journals (Sweden)

    Chonghua Zhou

    2011-06-01

    Full Text Available It is the last straw to clutch at to solve the urban traffic issue, to develop high-capacity rapid transit and promote transit priority. Characterized by low cost, short construction cycle and flexible development, Bus Rapid Transit (BRT has been favored by more and more cities in the world. The Platform Screen Doors (PSDs system is an important component at BRT stations, and it is original motive to be designed to satisfy the growing demand from BRT application to provide increased safety and comfort in the first. With the continual increased demand for BRT intelligent performance, the PSDs system is applied to get Bus Location Information with accurate position of arrival and departure at stop, to provide Real-Time Information (RTI for BRT passengers using PSDs/GPS compound location technology, to put into practice Bus Fleet Management (BFM. Considering the capability of accurate location, it can be applied to actualize Bus Sign Priority in the future. The authors are luck to take in part the practice of BRT system, especially in the BRT intelligent systems, the papers will introduce upwards application and conceive in detail.

  4. Measurements on and simulations of a biogas-fuelled bus

    International Nuclear Information System (INIS)

    Mathematical models for torque/fuel consumption and emissions have been studied for a biogas-fuelled bus used in urban traffic in Linkoeping, Sweden. It is noted that the cycle ECE R-49 is not representative for city buses, but that the Braunschweig cycle gives rather good agreement. 2 refs, 37 figs

  5. Measuring Bus Drivers' Occupational Stress Under Changing Working Conditions

    NARCIS (Netherlands)

    Hlotova, Y.; Cats, O.; Meijer, S.A.

    2014-01-01

    Stress is an immense problem in modern society; approximately half of all occupational illnesses are directly or indirectly related to stress. The work of a bus driver is typically associated with high stress levels that negatively influence individual well-being as well as workforce management. The

  6. Transformerless DC-DC Converter Using Cockcroft-Walton Voltage Multiplier to Obtain High DC Voltage

    Directory of Open Access Journals (Sweden)

    Meghana G Naik,

    2014-11-01

    Full Text Available In the present scenario the use of transformer for high voltages in converter circuit reduces the overall operating efficiency due to leakage inductance and use of transformer also increases the operational cost. . Therefore the proposed system is implemented with transformer less DC-DC converter so as to obtain high DC voltage with the use of nine stage Cockcroft-Walton (CW voltage multiplier. The proposed converter operates in CCM (continuous conduction mode, so that the converter switch stress, the switching losses are reduced. The DC voltage at the input of the proposed model is low and is boosted up by boost inductor (Ls in DC-DC converter stage and performs inverter operation. The number of stages in CW-voltage multiplier circuit is applied with low input pulsating DC (AC Voltage voltage where it is getting converted to high DC output voltage. The proposed converter switches operates at two independent frequencies, modulating (fsm andalternating (fsc frequency. The fsm operates at higher frequency of the output while the fsc operates at lower frequency of the desired output voltage ripple and the output ripples can be adjusted by the switch Sc1 and Sc2. The regulation of the output voltage is achieved by controlling the Duty ratio.The simulation is carried over by the MATLABSIMULINK.

  7. GeoBus: sharing science research with schools

    Science.gov (United States)

    Roper, Kathryn; Robinson, Ruth; Moorhouse, Ben

    2016-04-01

    GeoBus (www.geobus.org.uk) is an educational outreach project that was developed in 2012 by the Department of Earth and Environmental Sciences at the University of St Andrews, and it is currently sponsored by industry, NERC, The Crown Estate, and the Scottish Government. The aims of GeoBus are to support the teaching of Earth Science in secondary (middle and high) schools by providing teaching support to schools that have little or no experience in teaching this subject. This is, in part, done through the sharing of new science research outcomes and the experiences of young researchers with school pupils to provide a bridge between industry, higher education institutions, research councils and schools. Since its launch, over 40,000 pupils will have been involved in experiential Earth science learning activities in 190 different schools (over 400 separate visits) across the length and breadth of Scotland: many of these schools are in remote and disadvantaged regions. A new GeoBus project is under development within the Department of Earth Sciences at UCL in London. A key aim of GeoBus is to incorporate new research into our workshops with the main challenge being the development of appropriate resources that incorporate the key learning aims and requirements of the science and geography curricula. GeoBus works closely with researchers, teachers and educational practitioners to tailor the research outcomes to the curricula as much as possible. Over the past four years, GeoBus has developed 17 workshops, 5 challenge events and extensive field trips and each of these activities are trialled and evaluated within the university, and adjustments are made before the activities are delivered in schools. Activities are continually reviewed and further developments are made in response to both teacher and pupil feedback. This critical reflection of the project's success and impact is important to insure a positive and significant contribution to the science learning in

  8. Energy Performance Optimization of a Bus for Urban Public Transport

    Directory of Open Access Journals (Sweden)

    Paola Gori

    2013-08-01

    Full Text Available Nowadays many people use public transports in urban centres. Consequently, every day a lot of buses move within cities, trying to ensure the best service to citizens. During the year buses becomecrowded places and using an air conditioning system in constant operation, it tries to ensure a certain condition of comfort for the passengers on board. The aim of this study is to analyse and optimize the energy performance of a bus shell, identifying practical solutions that have not yet been adopted in order to reduce the impact of air conditioning on bus consumption and, therefore, on air pollution. For this reason it was decided to conduct a thermal analysis of a bus for public transport, in order to understandthe behaviour of the bus shell and to deduce possible optimization measures that have not yet been made until now. The analysis was carried out considering the hottest day of July and the coldest day ofJanuary, considering the conditions of operation based on the most common graphics TGM able to define the concentration of traffic city during the 24 hours per day. The study was done using the dynamicsimulation software TRNSYS. With this software it was possible to recreate faithfully the structure of the bus and the external environmental conditions, assessing the impact of different technical solutions for an improvement of internal conditions and a reduction of the cooling capacity required. Because the presence of passengers in public transport is considered like a “benefit” during the winter, the analysis started with the identification of a summer solution and the subsequent evaluation of this solution for the wintertime. The aim of this study was to optimize the bus shell and select the most appropriate solutions. Regarding the transparent surfaces it has been given importance to factors such as the thermal transmittance and the solar gain factor (g-value. Aware of the influence given by the solar radiation on the energy loads, we

  9. Piezometer completion report for borehold cluster sites DC-19, DC-20 and DC-22

    International Nuclear Information System (INIS)

    This report describes the design and installation of multi-level piezometers at borehole cluster sites DC-19, DC-20 and DC-22. The network of borehole cluster sites will provide facilities for multi-level water-level monitoring across the RRL for piezometer baseline monitoring and for large-scale hydraulic stress testing. These groundwater-monitoring facilities were installed between August 1983 and March 1984. Three series of piezometer nests (A-, C- and D-series) were installed in nine hydrogeologic units (monitoring horizons) within the Columbia River Basalt Group at each borehole cluster site. In addition to the piezometer facilities, a B-series pumping well was installed at borehole cluster sites DC-20 and DC-22. The A-series piezometer nest monitors the basal Ringold sediments and the Rattlesnake Ridge interbed. The C-series piezometer nests monitors the six deepest horizons, which are in increasing depth, the Priest Rapids interflow. 21 refs., 6 figs., 14 tabs

  10. A High-Efficiency Monolithic DC-DC PFM Boost Converter with Parallel Power MOS Technique

    Directory of Open Access Journals (Sweden)

    Hou-Ming Chen

    2013-01-01

    Full Text Available This paper presents a high-efficiency monolithic dc-dc PFM boost converter designed with a standard TSMC 3.3/5V 0.35 μm CMOS technology. The proposed boost converter combines the parallel power MOS technique with pulse-frequency modulation (PFM technique to achieve high efficiency over a wide load current range, extending battery life and reducing the cost for the portable systems. The proposed parallel power MOS controller and load current detector exactly determine the size of power MOS to increase power conversion efficiency in different loads. Postlayout simulation results of the designed circuit show that the power conversion is 74.9–90.7% efficiency over a load range from 1 mA to 420 mA with 1.5 V supply. Moreover, the proposed boost converter has a smaller area and lower cost than those of the existing boost converter circuits.

  11. Method for in-use measurement and evaluation of the activity, fuel use, electricity use, and emissions of a plug-in hybrid diesel-electric school bus.

    Science.gov (United States)

    Choi, Hyung-Wook; Frey, H Christopher

    2010-05-01

    The purpose of this study is to demonstrate a methodology for characterizing at high resolution the energy use and emissions of a plug-in parallel-hybrid diesel-electric school bus (PHSB) to support assessments of sensitivity to driving cycles and comparisons to a conventional diesel school bus (CDSB). Data were collected using onboard instruments for a first-of-a-kind prototype PHSB and a CDSB of the same chassis and engine, operated on actual school bus routes. The engine load was estimated on the basis of vehicle specific power (VSP) and an empirically derived relationship between VSP and engine manifold absolute pressure (MAP). VSP depends on speed, acceleration, and road grade. For the PHSB, the observed electrical discharge or recharge to the traction motor battery was characterized on the basis of VSP. The energy use and emission rates of the PHSB from tailpipe and electricity use were estimated for five real-world driving cycles and compared to the engine fuel use and emissions of the CDSB. The PHSB had the greatest advantage on arterial routes and less advantage on highway or local routes. The coupled VSP-MAP modeling approach enables assessment of a wide variety of driving conditions and comparisons of vehicles with different propulsion technologies.

  12. Method for in-use measurement and evaluation of the activity, fuel use, electricity use, and emissions of a plug-in hybrid diesel-electric school bus.

    Science.gov (United States)

    Choi, Hyung-Wook; Frey, H Christopher

    2010-05-01

    The purpose of this study is to demonstrate a methodology for characterizing at high resolution the energy use and emissions of a plug-in parallel-hybrid diesel-electric school bus (PHSB) to support assessments of sensitivity to driving cycles and comparisons to a conventional diesel school bus (CDSB). Data were collected using onboard instruments for a first-of-a-kind prototype PHSB and a CDSB of the same chassis and engine, operated on actual school bus routes. The engine load was estimated on the basis of vehicle specific power (VSP) and an empirically derived relationship between VSP and engine manifold absolute pressure (MAP). VSP depends on speed, acceleration, and road grade. For the PHSB, the observed electrical discharge or recharge to the traction motor battery was characterized on the basis of VSP. The energy use and emission rates of the PHSB from tailpipe and electricity use were estimated for five real-world driving cycles and compared to the engine fuel use and emissions of the CDSB. The PHSB had the greatest advantage on arterial routes and less advantage on highway or local routes. The coupled VSP-MAP modeling approach enables assessment of a wide variety of driving conditions and comparisons of vehicles with different propulsion technologies. PMID:20380435

  13. SunLine Transit Agency Advanced Technology Fuel Cell Bus Evaluation: First Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Chandler, K.

    2011-03-01

    This report describes operations at SunLine Transit Agency for their newest prototype fuel cell bus and five compressed natural gas (CNG) buses. In May 2010, SunLine began operating its sixth-generation hydrogen fueled bus, an Advanced Technology (AT) fuel cell bus that incorporates the latest design improvements to reduce weight and increase reliability and performance. The agency is collaborating with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to evaluate the bus in revenue service. This report provides the early data results and implementation experience of the AT fuel cell bus since it was placed in service.

  14. Implementation of an AMBA Advanced High Performance Bus protocol IP block

    OpenAIRE

    Mahendra Vucha Sandeep Magarde; Miss. Shruti Bhargava; Rishabh Singh Kurmi

    2011-01-01

    The design of an AMBA advanced high performance bus (AHB) protocol IP block is presented in this paper. The AHB (Advanced High-performance Bus) is a high-performance bus in AMBA (Advanced Microcontroller Bus Architecture) family. This AHB can be used in high clock frequency system modules. The AHB acts as the high-performance system backbone bus. AHB supports the efficient connection of processors, on-chip memories and off-chip external memory interfaces with low-power peripheral macro cell f...

  15. Alkaline quinone flow battery.

    Science.gov (United States)

    Lin, Kaixiang; Chen, Qing; Gerhardt, Michael R; Tong, Liuchuan; Kim, Sang Bok; Eisenach, Louise; Valle, Alvaro W; Hardee, David; Gordon, Roy G; Aziz, Michael J; Marshak, Michael P

    2015-09-25

    Storage of photovoltaic and wind electricity in batteries could solve the mismatch problem between the intermittent supply of these renewable resources and variable demand. Flow batteries permit more economical long-duration discharge than solid-electrode batteries by using liquid electrolytes stored outside of the battery. We report an alkaline flow battery based on redox-active organic molecules that are composed entirely of Earth-abundant elements and are nontoxic, nonflammable, and safe for use in residential and commercial environments. The battery operates efficiently with high power density near room temperature. These results demonstrate the stability and performance of redox-active organic molecules in alkaline flow batteries, potentially enabling cost-effective stationary storage of renewable energy. PMID:26404834

  16. A Novel High Gain DC-DC Step up Converter

    Directory of Open Access Journals (Sweden)

    M. Al Mamun

    2016-07-01

    Full Text Available High gain dc-dc converters are widely used to maximize the energy harvest for renewable energy systems, for example, photovoltaic systems and fuel cell. Conventional boost converters usually operates at extreme duty cycle to obtain high voltage gain. Operation at extreme duty cycle leads to reverse recovery problem at the switches, high conduction loss, electromagnetic interference etc. This paper proposes a very high gain dc-dc step up converter operating at very low duty cycle (i.e. duty cycle <0.5. The additional advantage of the proposed converter is that a single control signal is used for the switches which reduces the operation complexity. The steady-state theoretical analysis described in this paper is finally verified by simulation results

  17. Maintenance-free lead acid battery for inertial navigation systems aircraft

    Science.gov (United States)

    Johnson, William R.; Vutetakis, David G.

    1995-05-01

    Historically, Aircraft Inertial Navigation System (INS) Batteries have utilized vented nickel-cadmium batteries for emergency DC power. The United States Navy and Air Force developed separate systems during their respective INS developments. The Navy contracted with Litton Industries to produce the LTN-72 and Air Force contracted with Delco to produce the Carousel IV INS for the large cargo and specialty aircraft applications. Over the years, a total of eight different battery national stock numbers (NSNs) have entered the stock system along with 75 battery spare part NSNs. The Standard Hardware Acquisition and Reliability Program is working with the Aircraft Battery Group at Naval Surface Warfare Center Crane Division, Naval Air Systems Command (AIR 536), Wright Laboratory, Battelle Memorial Institute, and Concorde Battery Corporation to produce a standard INS battery. This paper discusses the approach taken to determine whether the battery should be replaced and to select the replacement chemistry. The paper also discusses the battery requirements, aircraft that the battery is compatible with, and status of Navy flight evaluation. Projected savings in avoided maintenance in Navy and Air Force INS Systems is projected to be $14.7 million per year with a manpower reduction of 153 maintenance personnel. The new INS battery is compatible with commercially sold INS systems which represents 66 percent of the systems sold.

  18. DC Microgrids—Part II

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Lu, Xiaonan; Quintero, Juan Carlos Vasquez;

    2016-01-01

    DC microgrids (MGs) have been gaining a continually increasing interest over the past couple of years both in academia and industry. The advantages of DC distribution when compared to its AC counterpart are well known. The most important ones include higher reliability and efficiency, simpler...... MG technology concerning typical power hardware topologies and their suitability for different emerging smart grid applications. Then, an overview of the state of the art in DC MG protection and grounding is provided. Owing to the fact that there is no zero current crossing, an arc that appears upon...

  19. DC-Compensated Current Transformer.

    Science.gov (United States)

    Ripka, Pavel; Draxler, Karel; Styblíková, Renata

    2016-01-01

    Instrument current transformers (CTs) measure AC currents. The DC component in the measured current can saturate the transformer and cause gross error. We use fluxgate detection and digital feedback compensation of the DC flux to suppress the overall error to 0.15%. This concept can be used not only for high-end CTs with a nanocrystalline core, but it also works for low-cost CTs with FeSi cores. The method described here allows simultaneous measurements of the DC current component. PMID:26805830

  20. DC-Compensated Current Transformer.

    Science.gov (United States)

    Ripka, Pavel; Draxler, Karel; Styblíková, Renata

    2016-01-20

    Instrument current transformers (CTs) measure AC currents. The DC component in the measured current can saturate the transformer and cause gross error. We use fluxgate detection and digital feedback compensation of the DC flux to suppress the overall error to 0.15%. This concept can be used not only for high-end CTs with a nanocrystalline core, but it also works for low-cost CTs with FeSi cores. The method described here allows simultaneous measurements of the DC current component.

  1. Hybrid posicast controller for a DC-DC buck converter

    OpenAIRE

    Kaithamalai Udhayakumar; Ponnusamy Lakshmi; Kandasamy Boobal

    2008-01-01

    A new Posicast compensated hybrid controller for the DC-DC Buck converter is investigated. Posicast is a feed forward compensator, which eliminates the overshoot in the step response of a lightly damped system. However, the traditional method is sensitive to variations in natural frequency. The new method described here reduces this undesirable sensitivity by using Posicast within the feedback loop. Design of the Posicast function is independent of computational delay. The new controller resu...

  2. Digital Control Technologies for Modular DC-DC Converters

    Science.gov (United States)

    Button, Robert M.; Kascak, Peter E.; Lebron-Velilla, Ramon

    2002-01-01

    Recent trends in aerospace Power Management and Distribution (PMAD) systems focus on using commercial off-the-shelf (COTS) components as standard building blocks. This move to more modular designs has been driven by a desire to reduce costs and development times, but is also due to the impressive power density and efficiency numbers achieved by today's commercial DC-DC converters. However, the PMAD designer quickly learns of the hidden "costs" of using COTS converters. The most significant cost is the required addition of external input filters to meet strict electromagnetic interference (MIAMI) requirements for space systems. In fact, the high power density numbers achieved by the commercial manufacturers are greatly due to the lack of necessary input filters included in the COTS module. The NASA Glenn Research Center is currently pursuing a digital control technology that addresses this problem with modular DC-DC converters. This paper presents the digital control technologies that have been developed to greatly reduce the input filter requirements for paralleled, modular DC-DC converters. Initial test result show that the input filter's inductor size was reduced by 75 percent, and the capacitor size was reduced by 94 percent while maintaining the same power quality specifications.

  3. 29 CFR 1926.441 - Batteries and battery charging.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Batteries and battery charging. 1926.441 Section 1926.441... for Special Equipment § 1926.441 Batteries and battery charging. (a) General requirements—(1... areas. (2) Ventilation shall be provided to ensure diffusion of the gases from the battery and...

  4. DC-SIGN/DC-SIGNR基因多态性与病原微生物感染%Polymorphisms of DC-SIGN/DC-SIGNR and pathogen infection

    Institute of Scientific and Technical Information of China (English)

    许利军; 潘晨; 李勤光

    2010-01-01

    DC-SIGN和DC-SIGNR是两种表达于DC表面的蛋白,被认为是许多病原微生物的黏附受体,参与很多病原微生物的感染.DC-SIGN和DC-SIGNR(DC-SIGN/DC-SIGNR)的多态性或许影响病原微生物的感染过程和结果.此文对DC-SIGN/DC-SIGNR的结构功能以及与HIV、HCV感染、肺结核、登革热的关系进行了综述.%DC-SIGN and DC-SIGNR are two surface proteins on dendritic cells with complex stmction, and are regarded as attachment receptors of many pathogens, DC-SIGN/DC-SIGNR participate in pathogen infection.Polymorphisms of DC-SIGN/DC-SIGNR probably influence the procedure and outcome of pathogen infection. In this article, the structure and function of DC-SIGN/DC-SIGNR are discussed as well as the relation between the DC-SIGN/DC-SIGNR and pathogens such as HIV, HCV infection, pulmonary tuberculosis, dengue fever.

  5. DC injection into low voltage AC networks

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This report summarises the results of a study investigating the impact of levels of injected DC current injections on a low voltage AC distribution network systems in order to recommend acceptable limits of DC from microgeneration. Relevant literature is reviewed, and the impact of DC levels in distribution transformers, transformer modelling, and instrumental transformers are discussed. The impact of DC in residual current devices (RCD) and in domestic electricity watt hour meters is examined along with DC enhanced corrosion, corrosion failure, and the measurement of DC current injection. Sources of DC injection outlined include DC from computer power supplies, network faults, geomagnetic phenomena, lighting circuits/dimmers, and embedded generators.

  6. Improving battery charging with solar panels

    Science.gov (United States)

    Boico, Florent Michael

    Recent technological developments in thin-film photovoltaics, such as amorphous silicon and hybrid dye sensitized photovoltaic (PV) cells are leading to new generations of portable solar arrays. These new arrays are lightweight, durable, flexible, and have been reported to achieve power efficiencies of up to 10%. Already, commercial-off-the-shelf arrays exist that have panels embedded in fabric that can be folded to dimensions of less than 12" x 12", yet are able to produce up to 50Watts of power at 12V. These new products make solar power available to various types of applications. In particular, military applications are emerging to give soldier a source of power that can always be at reach. In parallel with these developments, NiMH and Li-ion batteries are increasingly being used to power various equipment. Currently, the military is field testing solar charging of its batteries with portable solar arrays. However, so far, all known charge control algorithm have failed as they commonly falsely detect overcharge at random times in the charging and leave the battery partially charged. The goal of our research is to investigate the origins of failure in existing charge control algorithms and to propose adequate algorithms that would improve the battery charging. Additionally, ways to optimize the generated photovoltaic power is critical for portable solar application as the energy produced is limited. It is known that the use of a DC-DC converter between the solar panel and the load allows optimization of the power delivered by the solar panel when "Maximum Power Point Tracking" is utilized. Therefore we are developing new solutions that address the specific problem of Maximum Power Point Tracking for modular solar panels.

  7. Electrochemical accumulators batteries; Accumulateurs electrochimiques batteries

    Energy Technology Data Exchange (ETDEWEB)

    Ansart, F.; Castillo, S.; Laberty- Robert, C.; Pellizon-Birelli, M. [Universite Paul Sabatier, Lab. de Chimie des Materiaux Inorganiques et Energetiques, CIRIMAT, UMR CNRS 5085, 31 - Toulouse (France)] [and others

    2000-07-01

    It is necessary to storage the electric power in batteries to join the production and the utilization. In this domain progresses are done every days in the technics and also in the available materials. These technical days present the state of the art in this domain. Many papers were presented during these two days giving the research programs and recent results on the following subjects: the lithium batteries, the electrolytes performances and behaviour, lead accumulators, economic analysis of the electrochemical storage market, the batteries applied to the transportation sector and the telephones. (A.L.B.)

  8. Two hot spots in China's bus market%中国客车市场呈现两大热点

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ According to an analysis on statistics of production and sales of China's 70 bus enterprises in 2005, bus sales are expected to continue to grow this year, posing a better performance than that in the previous year, and the urban public bus transport, rural bus transport and export together will be a major motive power for pulling up growth of the industry.

  9. DC-SIGN and Immunoregulation

    Institute of Scientific and Technical Information of China (English)

    Tong Zhou; Yongxi Chen; Li Hao; Yanyun Zhang

    2006-01-01

    Dendritic cells (DCs) are known to be the most powerful professional antigen-presenting cells so far. It could activate primary immune response, and also downregulate immune response. DCs have a unique character of immunoregulation. DC-SIGN, a molecule designated as CD209, is one member of the C-type lectin superfamily. It is not only a pattern recognition receptor but implicated in immunoregulation of DCs. DC-SIGN has become hotspot of recent studies because of its important role in mediating DC adhesion, migration, inflammation,activating primary T cell, triggering immune response and participating in immune escape of pathogens and tumors. These studies on DC-SIGN involved in primary and secondary immune response and relevant mechanism will certainly provide us with a new method in treating and preventing certain diseases. Cellular & Molecular Immunology. 2006;3(4):279-283.

  10. Wind-powered asynchronous AC/DC/AC converter system. [for electric power supply regulation

    Science.gov (United States)

    Reitan, D. K.

    1973-01-01

    Two asynchronous ac/dc/ac systems are modelled that utilize wind power to drive a variable or constant hertz alternator. The first system employs a high power 60-hertz inverter tie to the large backup supply of the power company to either supplement them from wind energy, storage, or from a combination of both at a preset desired current; rectifier and inverter are identical and operate in either mode depending on the silicon control rectifier firing angle. The second system employs the same rectification but from a 60-hertz alternator arrangement; it provides mainly dc output, some sinusoidal 60-hertz from the wind bus and some high harmonic content 60-hertz from an 800-watt inverter.

  11. Transient Analysis of Large Scale PV Systems with Floating DC Section

    Directory of Open Access Journals (Sweden)

    George C. Lazaroiu

    2012-09-01

    Full Text Available The increasing penetration of renewable sources with power-electronic interfaces in power systems is raising technical problems and the overall efficiency of photovoltaic systems can decrease dramatically. In this context, the optimal layout for the photovoltaic system is required. The most adequate strategy to connect the renewable system to the electrical power grid or to supply the end users must be adopted. The present paper proposes a design layout of a PV plant using a DC bus system to improve the overall energy conversion efficiency. An analysis of steady-state system stability, voltage drop and DC cable conduction losses is conducted. The leakage currents to the ground are investigated through simulations. Experimental results are shown focused on the analysis of optimal layout of photovoltaic systems under particular operating conditions.

  12. Design of mine-used DC carrier telephone based on STM32

    Science.gov (United States)

    Chen, Goufan; Zhou, Hui; Zhan, Minhua; Wang, Jian

    2016-01-01

    Abide by the design principles of mine intrinsically safe circuit, according to the need of underground communication in coal mine, the paper proposed a design scheme of DC carrier telephone which can dial. The design circuit of the telephone is introduced in detail. The telephone's voice signals are generated by the microphone. After enlarged then the voice signals are modulated to frequency signals by LM567 chip. The frequency signals are coupled by transformer and then transmitted by 12V DC power supply line to the other voice terminals. In the voice terminal the signals are demodulated by LM567 demodulation circuit and enlarged by LM386, then, the amplified audio signals are output from a speaker. The dialing circuit is designed based on the STM32 MCU. The dial information is transmitted to the other telephone terminals by CAN bus. The measured distance calls is greater than 2000m, volume is larger than 85dB, good results.

  13. Codimension-Two Bifurcation Analysis in DC Microgrids Under Droop Control

    Science.gov (United States)

    Lenz, Eduardo; Pagano, Daniel J.; Tahim, André P. N.

    This paper addresses local and global bifurcations that may appear in electrical power systems, such as DC microgrids, which recently has attracted interest from the electrical engineering society. Most sources in these networks are voltage-type and operate in parallel. In such configuration, the basic technique for stabilizing the bus voltage is the so-called droop control. The main contribution of this work is a codimension-two bifurcation analysis of a small DC microgrid considering the droop control gain and the power processed by the load as bifurcation parameters. The codimension-two bifurcation set leads to practical rules for achieving a robust droop control design. Moreover, the bifurcation analysis also offers a better understanding of the dynamics involved in the problem and how to avoid possible instabilities. Simulation results are presented in order to illustrate the bifurcation analysis.

  14. Battery Energy Storage System for PV Output Power Leveling

    Directory of Open Access Journals (Sweden)

    Rajkiran Singh

    2014-01-01

    Full Text Available Fluctuating photovoltaic (PV output power reduces the reliability in power system when there is a massive penetration of PV generators. Energy storage systems that are connected to the PV generators using bidirectional isolated dc-dc converter can be utilized for compensating the fluctuating PV power. This paper presents a grid connected energy storage system based on a 2 kW full-bridge bidirectional isolated dc-dc converter and a PWM converter for PV output power leveling. This paper proposes two controllers: a current controller using the d-q synchronous reference and a phase-shift controller. The main function of the current controller is to regulate the voltage at the high-side dc, so that the voltage ratio of the high-voltage side (HVS with low-voltage side (LVS is equal to the transformer turns ratio. The phase-shift controller is employed to manage the charging and discharging modes of the battery based on PV output power and battery voltage. With the proposed system, unity power factor and efficient active power injection are achieved. The feasibility of the proposed control system is investigated using PSCAD simulation.

  15. Electric-vehicle batteries

    Science.gov (United States)

    Oman, Henry; Gross, Sid

    1995-02-01

    Electric vehicles that can't reach trolley wires need batteries. In the early 1900's electric cars disappeared when owners found that replacing the car's worn-out lead-acid battery costs more than a new gasoline-powered car. Most of today's electric cars are still propelled by lead-acid batteries. General Motors in their prototype Impact, for example, used starting-lighting-ignition batteries, which deliver lots of power for demonstrations, but have a life of less than 100 deep discharges. Now promising alternative technology has challenged the world-wide lead miners, refiners, and battery makers into forming a consortium that sponsors research into making better lead-acid batteries. Horizon's new bipolar battery delivered 50 watt-hours per kg (Wh/kg), compared with 20 for ordinary transport-vehicle batteries. The alternatives are delivering from 80 Wh/kg (nickel-metal hydride) up to 200 Wh/kg (zinc-bromine). A Fiat Panda traveled 260 km on a single charge of its zinc-bromine battery. A German 3.5-ton postal truck traveled 300 km with a single charge in its 650-kg (146 Wh/kg) zinc-air battery. Its top speed was 110 km per hour.

  16. Lifetime Improvement by Battery Scheduling

    NARCIS (Netherlands)

    Jongerden, Marijn R.; Haverkort, Boudewijn R.; Schmitt, Jens B.

    2012-01-01

    The use of mobile devices is often limited by the lifetime of their batteries. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to

  17. Lifetime improvement by battery scheduling

    NARCIS (Netherlands)

    Jongerden, Marijn R.; Haverkort, Boudewijn R.

    2011-01-01

    The use of mobile devices is often limited by the lifetime of its battery. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to t

  18. DC superconducting fault current limiter

    Science.gov (United States)

    Tixador, P.; Villard, C.; Cointe, Y.

    2006-03-01

    There is a lack of satisfying solutions for fault currents using conventional technologies, especially in DC networks, where a superconducting fault current limiter could play a very important part. DC networks bring a lot of advantages when compared to traditional AC ones, in particular within the context of the liberalization of the electric market. Under normal operation in a DC network, the losses in the superconducting element are nearly zero and only a small, i.e. a low cost, refrigeration system is then required. The absence of zero crossing of a DC fault current favourably accelerates the normal zone propagation. The very high current slope at the time of the short circuit in a DC grid is another favourable parameter. The material used for the experiments is YBCO deposited on Al2O3 as well as YBCO coated conductors. The DC limitation experiments are compared to AC ones at different frequencies (50-2000 Hz). Careful attention is paid to the quench homogenization, which is one of the key issues for an SC FCL. The University of Geneva has proposed constrictions. We have investigated an operating temperature higher than 77 K. As for YBCO bulk, an operation closer to the critical temperature brings a highly improved homogeneity in the electric field development. The material can then absorb large energies without degradation. We present tests at various temperatures. These promising results are to be confirmed over long lengths.

  19. Simulation and Implementation of Quasi Resonant DC-DC Converter

    Directory of Open Access Journals (Sweden)

    N. Devarajan

    2012-01-01

    Full Text Available Problem statement: A half-bridge LLC resonant converter with a voltage doubler rectifier has a simple structure and its Zero-Voltage-Switching (ZVS capability is excellent from zero to full load condition. But conduction loss is more due to high circulating energy thus reducing the system efficiency. Moreover a variable frequency control method makes the control circuits more complicated than those using the Pulse Width Modulation (PWM control method. Thus, DC drive has lower efficiency when it operates on light loads. Approach: To improve the efficiency of the DC drive under light loads, a PWM-controlled quasi-resonant converter is proposed .It has simple control circuits and less conduction loss compared to a half-bridge LLC resonant converter under light load conditions. The proposed converter has a half-bridge LLC resonant converter along with an auxiliary circuit. The load regulation of the proposed converter can be achieved by an auxiliary circuit. Thus the proposed converter is expected to be suitable sustaining power module for the efficiency enhancement of DC drives. As the magnetizing inductance of the proposed converter is larger the circulating energy is considerably reduced under light load conditions. In this study the operational principle, design and modeling of QRC DC-DC converters for DC drives are presented. The PWM controlled quasi resonant converter is implemented using PIC microcontroller 16F184A. Results: The capacitor filter in the output is replaced by pi filter to produce DC with minimum ripple. The experimental results and simulation results are compared. This converter has the advantages like reduced number of switches, reduced transformer and filter size, reduced ripple, reduced switching losses, reduced switching stresses and increased power density. Conclusion: The experimental results closely agree with the simulation results.

  20. Modeling, Dynamics, Bifurcation Behavior and Stability Analysis of a DC-DC Boost Converter in Photovoltaic Systems

    Science.gov (United States)

    Zhioua, M.; El Aroudi, A.; Belghith, S.; Bosque-Moncusí, J. M.; Giral, R.; Al Hosani, K.; Al-Numay, M.

    A study of a DC-DC boost converter fed by a photovoltaic (PV) generator and supplying a constant voltage load is presented. The input port of the converter is controlled using fixed frequency pulse width modulation (PWM) based on the loss-free resistor (LFR) concept whose parameter is selected with the aim to force the PV generator to work at its maximum power point. Under this control strategy, it is shown that the system can exhibit complex nonlinear behaviors for certain ranges of parameter values. First, using the nonlinear models of the converter and the PV source, the dynamics of the system are explored in terms of some of its parameters such as the proportional gain of the controller and the output DC bus voltage. To present a comprehensive approach to the overall system behavior under parameter changes, a series of bifurcation diagrams are computed from the circuit-level switched model and from a simplified model both implemented in PSIM© software showing a remarkable agreement. These diagrams show that the first instability that takes place in the system period-1 orbit when a primary parameter is varied is a smooth period-doubling bifurcation and that the nonlinearity of the PV generator is irrelevant for predicting this phenomenon. Different bifurcation scenarios can take place for the resulting period-2 subharmonic regime depending on a secondary bifurcation parameter. The boundary between the desired period-1 orbit and subharmonic oscillation resulting from period-doubling in the parameter space is obtained by calculating the eigenvalues of the monodromy matrix of the simplified model. The results from this model have been validated with time-domain numerical simulation using the circuit-level switched model and also experimentally from a laboratory prototype. This study can help in selecting the parameter values of the circuit in order to delimit the region of period-1 operation of the converter which is of practical interest in PV systems.

  1. Five-Level Active-Neutral-Point-Clamped DC/DC Converter for Medium Voltage DC Grids

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Chen, Zhe

    2016-01-01

    This paper proposes a five-level active-neutralpoint- clamped (5L-ANPC) dc/dc converter for applications in medium voltage dc (MVDC) grids. A modulation strategy is proposed for the 5L-ANPC dc/dc converter to generate multilevel voltage waveforms, which can effectively reduce voltage change rate dv...... effectively eliminate high voltage leaps caused by the dead time effect. In addition, a capacitor voltage control strategy is proposed for the 5L-ANPC dc/dc converter to ensure the balanced flying capacitor voltage and desired five-level voltage waveforms. Finally, simulation and experimental studies...

  2. A 7-Level Single DC Source Cascaded H-Bridge Multilevel Inverter with a Modified DTC Scheme for Induction Motor-Based Electric Vehicle Propulsion

    OpenAIRE

    Farid Khoucha; Khoudir Marouani; Mohamed Benbouzid; Abdelaziz Kheloui; Abdeslam Mamoune

    2013-01-01

    International audience This paper presents a new hybrid cascaded H-bridge multilevel inverter motor drive DTC scheme for electric vehicles where each phase of the inverter can be implemented using a single DC source. Traditionally, each phase of the inverter requires n DC source for (2n + 1) output voltage levels. In this paper, a scheme is proposed that allows the use of a single DC source as the first DC source which would be available from batteries or fuel cells, with the remaining (n ...

  3. DC-link Voltage Control to Compensate Voltage Deviation for PV–BESSs Integrated System in Low-Voltage (LV Networks

    Directory of Open Access Journals (Sweden)

    Lee Gyu-sub

    2016-01-01

    Full Text Available The exhaustion of fossil fuel and the greenhouse gas emission are one of the most significant energy and environmental issues, respectively. Photovoltaic (PV generators and battery energy storage systems (BESSs have been significantly increased for recent years. The BESSs are mainly used for smoothing active power fluctuation of the PV. In this paper, PV–BESSs integration of two DC/DC converters and one AC/DC converter is investigated and DC-link voltage control to compensate the AC voltage deviation is proposed for the PV‒BESS system in low-voltage (LV networks.

  4. A Desalination Battery

    KAUST Repository

    Pasta, Mauro

    2012-02-08

    Water desalination is an important approach to provide fresh water around the world, although its high energy consumption, and thus high cost, call for new, efficient technology. Here, we demonstrate the novel concept of a "desalination battery", which operates by performing cycles in reverse on our previously reported mixing entropy battery. Rather than generating electricity from salinity differences, as in mixing entropy batteries, desalination batteries use an electrical energy input to extract sodium and chloride ions from seawater and to generate fresh water. The desalination battery is comprised by a Na 2-xMn 5O 10 nanorod positive electrode and Ag/AgCl negative electrode. Here, we demonstrate an energy consumption of 0.29 Wh l -1 for the removal of 25% salt using this novel desalination battery, which is promising when compared to reverse osmosis (∼ 0.2 Wh l -1), the most efficient technique presently available. © 2012 American Chemical Society.

  5. PWM ZCS DC Motor Drive and DC Power Supply

    Directory of Open Access Journals (Sweden)

    Bardia Montazeri

    2011-01-01

    Full Text Available Following the extension and increase in capacity of power electronic elements, many convertors with special applications have been designed. Convertors such as rectifiers, AC and DC power supplies, AC and DC drivers and so on. At present, optimization of these convertors, decreasing loss and bringing down the electromagnetic interference are desired. In this paper, a DC to DC convertor for controlling the speed  of DC motor is designed and  one prototype is presented in which switching losses is close to zero and it has a very low electromagnetic interference. In this convertor, the switches  turn on and turn off approximately with zero current. The speed of motor is controlled by PWM.  This plan includes advantages of  PWM and resonant convertors.The disadvantages, such as ;  high switching losses and changing switching  frequency  for controlling output were removed. As switching frequency has a direct relation with switching losses, when losses decreased, it is possible to increase the frequency, then volume and weight of passive filter elements can be decreased. Besides, by decreasing the losses ,  the need of  heatsink , which is  the heavy and voluminous elements of convertors, can be removed.

  6. Experimental Study on a Passive Fuel Cell/Battery Hybrid Power System

    OpenAIRE

    Yong-Song Chen; Sheng-Miao Lin; Boe-Shong Hong

    2013-01-01

    A laboratory-scale passive hybrid power system for transportation applications is constructed and tested in this study. The hybrid power system consists of a fuel cell stack connected with a diode, a lithium-ion battery pack connected with a DC/DC power converter and another diode. The power converter is employed to regulate the output voltage of the battery pack. The dynamic responses of current and voltage of the stack to the start-up and acceleration of the load are experimentally investig...

  7. SIMULATING MODEL OF SYSTEM FOR MAXIMUM OUTPUT POWER OF SOLAR BATTERY

    Directory of Open Access Journals (Sweden)

    Abdul Majid Al-Khatib

    2005-01-01

    Full Text Available Simulating model and algorithm for control of electric power converter of a solar battery are proposed in the paper. Control device of D.C. step-down converter with pulse-width modulation is designed on microprocessor basis. Simulating model permits to investigate various operational modes of a solar battery, demonstrates a process with maximum power mode and is characterized by convenient user’s interface.

  8. StarBus+: Distributed Object Middleware Practice for Internet Computing

    Institute of Scientific and Technical Information of China (English)

    Huai-Min Wang; Yu-Feng Wang; Yang-Bin Tang

    2005-01-01

    In the past decade, the booming of Internet challenges the middleware in three aspects: quality of service,balance of changes and stabilization, and across-Internet integration. This paper presents our work on distributed object computing middleware technology for these challenges, as well as the research and development on StarBus+, which is a CORBA standard-compliant middleware suite with the features such as object request broker supporting multi-* quality of service, component model, and integration with Web Service. This paper comprehensively presents the design and characteristics of StarBns+, and demonstrates how StarBus+ is enhanced to address the challenges of Internet computing through three case studies: inter-enterprise integration over Internet, application evolution through dynamic reconfiguration,and great massive information system building. The paper also suggests some research directions which are important for Internet computing.

  9. Bus Encoder for Crosstalk Avoidance in RLC Modeled Interconnects

    Directory of Open Access Journals (Sweden)

    G. Nagendra Babu

    2012-02-01

    Full Text Available Most of the encoding methods proposed in recent years have dealt with only RC modeled VLSI interconnects. For deep sub micron technologies (DSM, on-chip inductive effects have increased due to faster clock speeds, smaller signal rise times and longer length of on-chip interconnects. All these issues raise the concern for cross talk, propagation delay and power dissipation of overall. Therefore, this research work introduces an efficient Bus Encoder using Bus Inverting (BI method. The proposed design dramatically reduces both cross talk and power dissipation in RLC modeled interconnects which makes it suitable for current high-speed low-power VLSI interconnects. The proposed model demonstrates an overall reduction of power dissipation and cross talk induced delay by 55.43% and 45.87%, respectively.

  10. Bus Vent Design Evolution for the Solar Dynamics Observatory

    Science.gov (United States)

    Woronowicz, Michael

    2010-01-01

    As a spacecraft undergoes ascent in a launch vehicle, its pressure environment transitions from one atmosphere to high vacuum in a matter of minutes. Venting of internal cavities is necessary to prevent the buildup of pressure differentials across cavity walls. Opposing the need to vent these volumes freely into space are thermal, optical, and electrostatic requirements for limiting or prohibiting the intrusion of unwanted energy into the same cavities. Bus vent design evolution is discussed for the Solar Dynamics Observatory. Design changes were influenced by a number of factors and concerns, such as contamination control, electrostatic discharge, changes in bus material, and driving fairing ascent pressure for a launch vehicle that was just entering service as this satellite project had gotten underway.

  11. Implementation of I 2C Master Bus Protocol on FPGA

    Directory of Open Access Journals (Sweden)

    Regu Archana

    2014-10-01

    Full Text Available The focus of this paper is on I 2C (Inter-Integrated Circuit protocol interface between Master Bus protocol and slave. Here we are interfacing between micro-controller and DS1307. I 2C bus protocol sends 8 bit data from micro-controller to DS1307. This module was designed in VHDL and simulated and synthesized using Xilinx ISE Design Suite 14.2. I 2C and optimized for area and power. This concept is widely applicable from any high speed device or low speed device to any low speed device or high speed device. This module acts as a slave for the DS1307 at the same time acts like a master for the micro-controller device which can be considered as a slave. . It can be used to interface low speed peripherals like motherboard, embedded system, mobile phones, set top boxes, DVD, PDA’s or other electronic devices.

  12. Hardware Engines for Bus Encryption: A Survey of Existing Techniques

    CERN Document Server

    Elbaz, R; Sassatelli, G; Guillemin, P; Anguille, C; Bardouillet, M; Buatois, C; Rigaud, J B

    2011-01-01

    The widening spectrum of applications and services provided by portable and embedded devices bring a new dimension of concerns in security. Most of those embedded systems (pay-TV, PDAs, mobile phones, etc...) make use of external memory. As a result, the main problem is that data and instructions are constantly exchanged between memory (RAM) and CPU in clear form on the bus. This memory may contain confidential data like commercial software or private contents, which either the end-user or the content provider is willing to protect. The goal of this paper is to clearly describe the problem of processor-memory bus communications in this regard and the existing techniques applied to secure the communication channel through encryption - Performance overheads implied by those solutions will be extensively discussed in this paper.

  13. Environmental assessment of 9 European public bus transportation systems

    DEFF Research Database (Denmark)

    Nanaki, Eva; Koroneos, Christophis; Roset, Jaume;

    2017-01-01

    that affect the production of carbon dioxide (CO2) as well as of air pollutants, in 9 major European cities, aiming to provide a comprehensive overview of the actual knowledge on the atmospheric pollution from public transportation systems. CO2 emissions as well as air pollutants, such as CO, HC, PM, NOx......The transportation sector is one of the largest sources of EU’s greenhouse gas emissions. In 2011, transportation represented approximately 25 percent of total EU’s greenhouse gas emissions. Urban mobility accounts for 40% of all CO2 emissions of road transport and up to 70% of other pollutants...... are calculated for the diesel and CNG bus fleets of the European cities under study. Finally the environmental benefits, in terms of CO2 and CO, HC, PM, NOx emissions reductions, from the penetration of different biodiesel blends (from B10 to B100) to the bus fleets are estimated....

  14. Health effect of a bus ride in an urban environment

    Energy Technology Data Exchange (ETDEWEB)

    Takano, T.

    1983-07-01

    Health effects on subjects during a bus drive on an urban road were investigated in a real situation. Leukocyte count, adrenalin level in blood and urine, noradrenalin and dopamine in urine, diastolic blood pressure, and index of vascular resistance increased significantly on the drive day compared with the control day. A bus drive on an urban road induced enhanced sympathetic-adreno-medullary activity in real life as a result of the comprehensive effect of various factors. The concentrations of air pollutants were excessively high on the road, and correlated with traffic volume. It was concluded that the interactions between psychogenic, physical nonspecific and physical specific effects should be taken into consideration when evaluating human health effects of air pollution in the urban environment.

  15. THE DESIGN OF VMEBUS BRIDGE CONTROLLER WITH SHARC BUS

    Institute of Scientific and Technical Information of China (English)

    Wang Min; Wu Shunjun; Su Tao

    2005-01-01

    Targeting at the high expense and inflexibility to realize VMEbus bridge controller by professional Integrated Circuit (IC), this paper presents a scheme of adopting CPLD/FPGA (Complicated Programmable Logic Device/Field Programmable Gate Array) to design bridge controller between VMEbus and local bus. SHARC DSP (Digital Signal Processor) bus is an example. It has functions of nearly entire master/slave interface of VMEbus, and can act as DMA (Direct Memory Access) controller and perform block transfer in DMA or master processor initiative way without length limit. External circuit of the design is very simple. In comparison with special ICs, it has high performance to price ratio and can be easily applied to local buses of other processors with quite a little modification.

  16. Technology Update of a Control System Trough Corba Bus

    CERN Document Server

    Bertocchi, A; Buceti, G; Centioli, C; Muzio, D D; Iannone, F; Mazza, G; Panella, M; Vitale, V

    2001-01-01

    After more than 10 years of activity, FTU (Frascati Tokamak Upgrade) has to face the problem of taking advantage of the new hardware and software technology saving all the investments yet done. So, for example, the 20 years old Westinghouse PLCs (communicating only through a serial line) have to be leaved in operation while a web-based tool has to be released for plan monitoring purpose. CORBA bus has been demonstrated to be the answer to set up the communication between old and new hardware and software blocks. On FTU the control system is based on Basestar, a Digital/Compaq software suite. We will describe how the real time database of Basestar is now accessed by Java graphic tools, LabView and, in principle, any package accepting external routines. An account will be also done in the data acquisition area where a Camac serial highway driver has been integrated in the new architecture still through the CORBA bus

  17. Heat storage for a bus petrol internal-combustion engine

    Science.gov (United States)

    Vasiliev, Leonard L.; Burak, Victor S.; Kulakov, Andry G.; Mishkinis, Donatas A.; Bohan, Pavel V.

    The heat storage (HS) system for pre-heating a bus petrol internal combustion engine to starting was mathematically modelled and experimentally investigated. The development of such devices is an extremely urgent problem especially for regions with a cold climate. We discuss how HS works on the effect of absorption and rejection of heat energy at a solid-liquid phase change of a HS substance. In the first part of the paper a numerical method to calculate the HS mass-dimensional parameters and their characteristics are described. In the experimental part of the paper results are given of experiments on the pre-heating device aiding to start a carburettor engine under operational conditions and analysis of data received. Practical confirmation of the theoretical development of HS devices for a bus engine for starting by pre-heating is given.

  18. Investigation on full distribution CNC system based on SERCOS bus

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A full distribution CNC system based on SERCOS bus is studied in accordance with the limitations of traditional PC-based motion card.The conventional PC-based motion control card is dispersed into several autonomous intelligent servo-control units with the function of servo driver.The autonomous intelligent servocontrol units realize the loop control of position,velocity and current.Interpolation computation is completed in PC and the computational results are transferred to every autonomous intelligent servo-control unit by high speed SERCOS bus.Software or hardware synchronization technology is used to ensure all servomotors are successive and synchronously running.The communication and synchronization technology of SERCOS are also researched and the autonomous intelligent servo-control card is developed byself.Finally,the experiment of circle contour process on a prototype system proves the feasibility.

  19. Lithium ion battery production

    International Nuclear Information System (INIS)

    Highlights: ► Sustainable battery manufacturing focus on more efficient methods and recycling. ► Temperature control and battery management system increase battery lifetime. ► Focus on increasing battery performance at low- and high temperatures. ► Production capacity of 100 MWh equals the need of 3000 full-electric cars. - Abstract: Recently, new materials and chemistry for lithium ion batteries have been developed. There is a great emphasis on electrification in the transport sector replacing part of motor powered engines with battery powered applications. There are plans both to increase energy efficiency and to reduce the overall need for consumption of non-renewable liquid fuels. Even more significant applications are dependent on energy storage. Materials needed for battery applications require specially made high quality products. Diminishing amounts of easily minable metal ores increase the consumption of separation and purification energy and chemicals. The metals are likely to be increasingly difficult to process. Iron, manganese, lead, zinc, lithium, aluminium, and nickel are still relatively abundant but many metals like cobalt and rare earths are becoming limited resources more rapidly. The global capacity of industrial-scale production of larger lithium ion battery cells may become a limiting factor in the near future if plans for even partial electrification of vehicles or energy storage visions are realized. The energy capacity needed is huge and one has to be reminded that in terms of cars for example production of 100 MWh equals the need of 3000 full-electric cars. Consequently annual production capacity of 106 cars requires 100 factories each with a 300 MWh capacity. Present day lithium ion batteries have limitations but significant improvements have been achieved recently . The main challenges of lithium ion batteries are related to material deterioration, operating temperatures, energy and power output, and lifetime. Increased lifetime

  20. Lithium battery management system

    Science.gov (United States)

    Dougherty, Thomas J.

    2012-05-08

    Provided is a system for managing a lithium battery system having a plurality of cells. The battery system comprises a variable-resistance element electrically connected to a cell and located proximate a portion of the cell; and a device for determining, utilizing the variable-resistance element, whether the temperature of the cell has exceeded a predetermined threshold. A method of managing the temperature of a lithium battery system is also included.

  1. Polyoxometalate flow battery

    Science.gov (United States)

    Anderson, Travis M.; Pratt, Harry D.

    2016-03-15

    Flow batteries including an electrolyte of a polyoxometalate material are disclosed herein. In a general embodiment, the flow battery includes an electrochemical cell including an anode portion, a cathode portion and a separator disposed between the anode portion and the cathode portion. Each of the anode portion and the cathode portion comprises a polyoxometalate material. The flow battery further includes an anode electrode disposed in the anode portion and a cathode electrode disposed in the cathode portion.

  2. Nanotubes for Battery Applications

    OpenAIRE

    Nordlinder, Sara

    2005-01-01

    Nanomaterials have attracted great interest in recent years, and are now also being considered for battery applications. Reducing the particle size of some electrode materials can increase battery performance considerably, especially with regard to capacity, power and rate capability. This thesis presents a study focused on the performance of such a material, vanadium oxide nanotubes, as cathode material for rechargeable lithium batteries. These nanotubes were synthesized by a sol-gel process...

  3. An Optimization Model for the Selection of Bus-Only Lanes in a City.

    Directory of Open Access Journals (Sweden)

    Qun Chen

    Full Text Available The planning of urban bus-only lane networks is an important measure to improve bus service and bus priority. To determine the effective arrangement of bus-only lanes, a bi-level programming model for urban bus lane layout is developed in this study that considers accessibility and budget constraints. The goal of the upper-level model is to minimize the total travel time, and the lower-level model is a capacity-constrained traffic assignment model that describes the passenger flow assignment on bus lines, in which the priority sequence of the transfer times is reflected in the passengers' route-choice behaviors. Using the proposed bi-level programming model, optimal bus lines are selected from a set of candidate bus lines; thus, the corresponding bus lane network on which the selected bus lines run is determined. The solution method using a genetic algorithm in the bi-level programming model is developed, and two numerical examples are investigated to demonstrate the efficacy of the proposed model.

  4. Capacity models on expressway near a bus bay stop with an access

    Institute of Scientific and Technical Information of China (English)

    张洪宾; 孙小端; 贺玉龙; 宇仁德

    2015-01-01

    To determinate the expressway capacity near a bus bay stop with an access, capacity models on the expressway near a bus stop with an access were developed on the basis of gap acceptance theory and queuing theory. Depending on a bus stop position to an entrance or an exit ramp, the capacity models were developed for four cases. Bus bay stops with overflow and bus bay stops without overflow were considered. A comparison of simulation experiment and model calculation was carried out. Results show that the suggested models have high accuracy and reliability, at bus arrival rate below 60 vehicles per hour (veh/h) or vehicle volumes at the entrance and the exit below 200 passenger cars units per hour (pcu/h), and there are no significant difference in the capacities for four cases. When bus arrival rate is above 240 veh/h, the capacities of all four cases will decline rapidly. With berth number increasing, the increasing of the capacities is no obvious for four cases. As the bus arrival rate and vehicle volumes at the entrance and the exit increase, bus stops located downstream of an entrance and upstream of an exit have a remarkably effect on the capacities. The latter case is much heavier than the former. Those results can be used to traffic design and optimization on urban expressway near a bus stop with an access.

  5. Common Traffic Violations of Bus Drivers in Urban China: An Observational Study.

    Directory of Open Access Journals (Sweden)

    Qiqi Wang

    Full Text Available To report common traffic violations in bus drivers and the factors that influence those violations in urban China.We conducted an observational study to record three types of traffic violations among bus drivers in Changsha City, China: illegal stopping at bus stations, violating traffic light signals, and distracted driving. The behaviors of bus drivers on 32 routes (20% of bus routes in the city were observed. A two-level Poisson regression examined factors that predicted bus driver violations.The incidence of illegal stopping at bus stations was 20.2%. Illegal stopping was less frequent on weekends, sunny days, and at stations with cameras, with adjusted incidence rate ratios (IRRs of 0.81, 0.65 and 0.89, respectively. The incidence of violating traffic light signals was 2.2%, and was lower on cloudy than sunny days (adjusted IRR: 0.60. The incidence of distracted driving was 3.3%. The incidence of distracted driving was less common on cloudy days, rainy or snowy days, and foggy/windy/dusty days compared to sunny days, with adjusted IRRs of 0.54, 0.55 and 0.07, respectively.Traffic violations are common in bus drivers in urban China and they are associated with the date, weather, and presence of traffic cameras at bus station. Further studies are recommended to understand the behavioral mechanisms that may explain bus driver violations and to develop feasible prevention measures.

  6. BUS BAY PERFORMANCE AND ITS INFLUENCE ON THE CAPACITY OF ROAD NETWORK IN DAR ES SALAAM

    Directory of Open Access Journals (Sweden)

    Nurdin K. Mushule

    2012-01-01

    Full Text Available One of major problems facing motorists in Dar es Salaam city today is congestion. Bus bays have a significant influence on the capacity of a roadway because they interfere with passing vehicles primarily when buses maneuver to pull into and out of bus bays. Bus bay stops will also interfere with vehicles movement if bus demand exceeds the bus bay capacity resulting in some buses waiting in the travel lane until the buses occupying the bay exit the bay. This paper presents the results of a study which was carried out to evaluate the bus bay performance and its influence on the capacity of the roadway network in the city of Dar es Salaam. The case study area covered 11 bus stops along Morogoro road from Ubungo to Magomeni Mapipa. Capacity of bus bays was studied using procedure outlined in the Transit Capacity and Quality of Service Manual of 2003. This enabled the researcher to determine parameters such as dwell times and clearance times which are major determinants of bus stop capacity. The results indicate that only 18% of the bus bay stops studied did not have adequate capacity to cater for the available demand. 9% did not have adequate capacity during peak hours but the capacity was adequate during off-peak hours. The remaining 73% of bus bay stops possess adequate capacity all the time. Although most bus bay stops studied possess adequate capacity, severe congestion was observed at these locations. This is due to erratic behavior of bus drivers who do not utilize the provided space for them to drop off and pick up passengers. Clearly, this is an area that requires more strict enforcement in order to ease the congestion problem in the city by operating the existing capacity more efficiently."

  7. City of Chula Vista hydrogen fuel cell bus demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    Gustafson, B.; Bamberger, B.

    1996-10-01

    Hydrogen as an energy carrier and fuel has potential for various uses including electricity, commercial, residential, transportation, and industrial. It is an energy carrier that can be produced from a variety of primary sources and potentially can accomplish these various uses while significantly reducing pollution by substituting for or reducing the use of fossil fuels. One of the most immediate and potentially viable roles for hydrogen as an energy carrier will be its use as a transportation fuel, especially in densely populated urban areas where automotive emissions contribute significantly to air pollution. The Department of Energy`s commitment to research and development of hydrogen as an alternative fuel, and California`s Zero Emission Vehicle (ZEV) requirements, both provide the impetus and favorable circumstance for demonstrating hydrogen as a transportation fuel on an urban bus system. The purpose of this project is to demonstrate the feasibility of using solid polymer fuel cells in a hydrogen-powered electric drive system for an urban transit bus application. Fuel cell buses use hydrogen fuel and oxygen from the air to produce electrical power with the only byproduct being pure water. Proton Exchange Membrane (PEM) fuel cells are proposed for this project. Current evidence suggests that fuel cells, which rely on hydrogen and a process known as proton exchange to generate their power, appear to have an infinite life span. All exhaust pollution is completely eliminated, resulting in a Zero Emission Vehicle (ZEV). An urban bus system offers the potential for developing a market for the production of hydrogen propulsion technology due to extensive vehicular use in densely populated areas experiencing pollution from numerous sources, and because the central garaging facilities or the bus system facilitates fueling and maintenance functions.

  8. System investigation H2 bus fleet (technology, regulations, future development)

    International Nuclear Information System (INIS)

    In cooperation with Ansaldo Ricerche, ICIL have compiled a technical catalogue, providing the impartial descriptions, both of existing technology and regulations, and the likely future developments of these, as to remedy the first problem faced by a potential hydrogen bus fleet operator viz the absence of an impartial description of the available vehicle and fuels systems together with the absence of a description of regulatory and safety factors which need consideration. (orig.)

  9. Market brief : the alternative fuels bus market in India

    International Nuclear Information System (INIS)

    In 2003, alternative fuel bus technologies in India were valued at approximately $1.5 billion. There are an estimated 600,000 buses in India, of which 21 per cent are owned by public transit. Bus production is currently 33,000 per year and increasing at 4 per cent annually. The main alternative fuel bus technologies include fuel cells, compressed natural gas (CNG) and liquefied petroleum gas (LPG). Since urban centres in India are among the most polluted in the world, demand for these technologies is strong. India is ranked fifth in the world in terms of vehicles converted to natural gas. In 2003, New Delhi switched from diesel to CNG fuel for buses but has faced challenges because there is no well-developed underground distribution system and refilling times are long due to weak pressure at fueling stations. India's new $28 million fuel cell bus development project aims to place 8 fuel cell powered buses with the Delhi Transport Corporation. This market brief describes the potential for Canadian suppliers to enter into joint ventures to establish local production facilities and transfer technology expertise. It describes the key factors shaping market growth with particular reference to sector reform, and opportunities with actual and planned projects. The competitive environment was also discussed with reference to local capabilities, international competition, Canadian position, and a competitive advantage through Canadian government policies and initiatives. A section of the report on public-sector customers listed the companies that buy alternative fuel buses in India. Considerations for market-entry in India were also outlined

  10. Modelling urban bus transport emissions in Santiago de Cuba

    OpenAIRE

    Warren, James; Avila, Jordi Mirabent

    2010-01-01

    This study described and focuses on the public transport bus system in Santiago de Cuba. Specifically we explore the fuel consumption of the various diesel buses over a three year period from 2007 to 2009 and with a forecast for the forthcoming years. The study considers the potential for fuel savings through a variety of methods which are each described and then modelled. Pollution is also calculated for a variety of scenarios and some suggestions are made in order to lower the overall...

  11. Virtual Instrument Based on GPIB Interface Bus1

    Institute of Scientific and Technical Information of China (English)

    Xiao,Ying; Qi,Hanhong

    2004-01-01

    In this paper, we introduced the technique of GPIB businterface. Through the controlling of the GPIB interface board,the computer controlled the current source and the voltmeter, both of which have GPIB bus interface, and a virtual instrument testing system for I~V curve was composed. The virtual instrument front panel and the background graphical control program in Labview environment accomplish virtual instrument testing task along with the hardware system.

  12. An asynchronous controller for a daisychainable vme bus interrupter

    OpenAIRE

    Wollowski, Ralf; Beister, Jochen; Kuhn, Matthias

    1999-01-01

    An interrupter for use in a daisy-chained VME bus interrupt system has beendesigned and implemented as an asynchronous sequential circuit. The concur-rency of the processes posed a design problem that was solved by means of asystematic design procedure that uses Petri nets for specifying system and in-terrupter behaviour, and for deriving a primitive flow table. Classical designand additional measures to cope with non-fundamental mode operation yieldeda coded state-machine representation. Thi...

  13. FAKTOR PENYEBAB KERUSAKAN SISTEM MESIN PADA BUS APTB PPD

    OpenAIRE

    Laela Chairani; Yulita Veranda Usman; Nur Yulianti Hidayah

    2015-01-01

    Comfort and safety of public transportation, particularly APTB PPD buses, becomes high expectations for its customers. Those expectations must be supported by the application of a good engine maintenance system. By using the method of Reliability Centered Maintenance may be determined appropriate actions to mitigate damage. From the analysis known the failures of the APTB PPD bus are malfunctions of the fuel engine, power transfer systems, difficulty to move the gear lever, and lubricating sy...

  14. BC Transit Fuel Cell Bus Project: Evaluation Results Report

    Energy Technology Data Exchange (ETDEWEB)

    Eudy, L.; Post, M.

    2014-02-01

    This report evaluates a fuel cell electric bus demonstration led by British Columbia Transit (BC Transit) in Whistler, Canada. BC Transit is collaborating with the California Air Resources Board and the U.S. Department of Energy's National Renewable Energy Laboratory to evaluate the buses in revenue service. This evaluation report covers two years of revenue service data on the buses from April 2011 through March 2013.

  15. Battery Thermal Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Keyser, Matthew; Saxon, Aron; Powell, Mitchell; Shi, Ying

    2016-06-07

    This poster shows the progress in battery thermal characterization over the previous year. NREL collaborated with U.S. DRIVE and USABC battery developers to obtain thermal properties of their batteries, obtained heat capacity and heat generation of cells under various power profiles, obtained thermal images of the cells under various drive cycles, and used the measured results to validate thermal models. Thermal properties are used for the thermal analysis and design of improved battery thermal management systems to support achieve life and performance targets.

  16. Edison Revisited: Should we use DC circuits for lighting in commercial buildings?

    International Nuclear Information System (INIS)

    We examine the economic feasibility of using dedicated DC circuits to operate lighting in commercial buildings. We compare light-emitting diodes (LEDs) and fluorescents that are powered by either a central DC power supply or traditional AC grid electricity, with and without solar photovoltaics (PV) and battery back-up. Using DOE performance targets for LEDs and solar PV, we find that by 2012 LEDs have the lowest levelized annualized cost (LAC). If a DC voltage standard were developed, so that each LED fixture's driver could be eliminated, LACs could decrease, on average, by 5% compared to AC LEDs with a driver in each fixture. DC circuits in grid-connected PV-powered LED lighting systems can lower the total unsubsidized capital costs by 4–21% and LACs by 2–21% compared to AC grid-connected PV LEDs. Grid-connected PV LEDs may match the LAC of grid-powered fluorescents by 2013. This outcome depends more on manufacturers' ability to produce LEDs that follow DOE's lamp production cost and efficacy targets, than on reducing power electronics costs for DC building circuits and voltage standardization. Further work is needed to better understand potential safety risks with DC distribution and to remove design, installation, permitting, and regulatory barriers. - Highlights: ► We model a 48,000 ft2 commercial building lighting system with AC and DC circuits. ► At 2012 efficacies and costs, LEDs are lowest levelized annual cost (LAC) option. ► DC LEDs can lead from an LAC increase of 5% to a decrease of 15% (vs. AC LEDs). ► Grid-connected DC LEDs with PV can lower LACs by 2–21% (vs. PV-AC LEDs). ► PV-DC LEDs may match the LAC of grid-powered AC fluorescents by ∼2013.

  17. Single-Phase PFC Converter for Plug-in Hybrid Electric Vehicle Battery Chargers

    OpenAIRE

    Shakil Ahamed Khan; Md. Ismail Hossain; Mousumi Aktar

    2012-01-01

    In this paper, a front end ac–dc power factor correction topology is proposed for plug-in hybrid electric vehicle (PHEV) battery charging. The topology can achieve improved power quality, in terms of power factor correction, reduced total harmonic distortion at input ac mains, and precisely regulated dc output. Within this context, this paper introduces a boost converter topology for implementing digital power factor correction based on low cost digital signal controller that operates the con...

  18. Double Resonant Topology for 72V Battery Charger used in a Hybrid Electric Locomotive - Study and Experimental Validation

    OpenAIRE

    BUTTERBACH, S; DE-BERNARDINIS, A; Lallemand, R; Coquery, G.; JEUNESSE, A; EVAIN, Y; AUBIN, PH

    2010-01-01

    This work deals with the study, adaptation and experimental validation of a 9kW lead-acid battery charger used to feed the 72VDC bus inside the hybrid electric locomotive demonstrator in the frame of the French research project PLATHEE. The topology of the charger is based on a high frequency double resonant series-parallel circuit which allows soft switching, losses minimization, reduction of passive component weight and facilitates system integration. Specific charging and floating modes we...

  19. Evaluation of Bus Vibration Comfort Based on Passenger Crowdsourcing Mode

    Directory of Open Access Journals (Sweden)

    Hong Zhao

    2016-01-01

    Full Text Available Vibration comfort is an important factor affecting the quality of service (QoS of bus. In order to make people involved in supervising bus’s vibration comfort and improve passengers’ riding experience, a novel mode of passenger crowdsourcing is introduced. In this paper, comfort degree of bus vibration is calculated from bus’s vibration signals collected by passengers’ smartphones and sent through WiFi to the Boa web server which shows the vibration comfort on the LCD deployed in bus and maybe trigger alarm lamp when the vibration is beyond the threshold. Three challenges here have been overcome: firstly, space coordinate transformation algorithm is used to solve the constant drift of signals collected; secondly, a low-pass filter is designed to isolate gravity from signals real-timely via limited computing resources; thirdly, an embedded evaluation system is developed according to the calculation procedure specified by criterion ISO 2631-1997. Meanwhile, the model proposed is tested in a practical running environment, the vibration data in whole travel are recorded and analyzed offline. The results show that comfort degree of vibration obtained from the experimental system is identical with the truth, and this mode is proved to be effective.

  20. The AI Bus architecture for distributed knowledge-based systems

    Science.gov (United States)

    Schultz, Roger D.; Stobie, Iain

    1991-01-01

    The AI Bus architecture is layered, distributed object oriented framework developed to support the requirements of advanced technology programs for an order of magnitude improvement in software costs. The consequent need for highly autonomous computer systems, adaptable to new technology advances over a long lifespan, led to the design of an open architecture and toolbox for building large scale, robust, production quality systems. The AI Bus accommodates a mix of knowledge based and conventional components, running on heterogeneous, distributed real world and testbed environment. The concepts and design is described of the AI Bus architecture and its current implementation status as a Unix C++ library or reusable objects. Each high level semiautonomous agent process consists of a number of knowledge sources together with interagent communication mechanisms based on shared blackboards and message passing acquaintances. Standard interfaces and protocols are followed for combining and validating subsystems. Dynamic probes or demons provide an event driven means for providing active objects with shared access to resources, and each other, while not violating their security.