Hydropower generation and storage, transmission constraints and market power

International Nuclear Information System (INIS)

Johnsen, T.A.

2001-01-01

We study hydropower generation and storage in the presence of uncertainty about future inflows, market power and limited transmission capacity to neighboring regions. Within our simple two-period model, market power leads to too little storage. The monopolist finds it profitable to produce more than the competitive amount in the first period and thereby stores little water in the first of two periods in order to become import constrained in the second period. In addition, little storage reduces the probability of becoming export constrained in the second period, even if the second period exhibits large inflow. Empirical findings for an area in the western part of Norway with only hydropower and high ownership concentration at the supply side, fit well to our theoretical model. We apply a numerical model to examine various policies to reduce the inefficiencies created by the local monopoly. Transmission investments have two effects. First, the export possibilities in the first period increase. More export leads to lower storage in the first period. Second, larger import capacity reduces the market power problem in the second period. The two opposite effects of transmission investments in a case with market power may be unique to hydropower systems. Introducing financial transmission rights enhance the market power of the monopolist in our model. Price caps in both or in the second period only, reduce the strategic value of water storage. (Author)

Transmission-line-circuit model of an 85-TW, 25-MA pulsed-power accelerator

Science.gov (United States)

Hutsel, B. T.; Corcoran, P. A.; Cuneo, M. E.; Gomez, M. R.; Hess, M. H.; Hinshelwood, D. D.; Jennings, C. A.; Laity, G. R.; Lamppa, D. C.; McBride, R. D.; Moore, J. K.; Myers, A.; Rose, D. V.; Slutz, S. A.; Stygar, W. A.; Waisman, E. M.; Welch, D. R.; Whitney, B. A.

2018-03-01

We have developed a physics-based transmission-line-circuit model of the Z pulsed-power accelerator. The 33-m-diameter Z machine generates a peak electrical power as high as 85 TW, and delivers as much as 25 MA to a physics load. The circuit model is used to design and analyze experiments conducted on Z. The model consists of 36 networks of transmission-line-circuit elements and resistors that represent each of Zs 36 modules. The model of each module includes a Marx generator, intermediate-energy-storage capacitor, laser-triggered gas switch, pulse-forming line, self-break water switches, and tri-plate transmission lines. The circuit model also includes elements that represent Zs water convolute, vacuum insulator stack, four parallel outer magnetically insulated vacuum transmission lines (MITLs), double-post-hole vacuum convolute, inner vacuum MITL, and physics load. Within the vacuum-transmission-line system the model conducts analytic calculations of current loss. To calculate the loss, the model simulates the following processes: (i) electron emission from MITL cathode surfaces wherever an electric-field threshold has been exceeded; (ii) electron loss in the MITLs before magnetic insulation has been established; (iii) flow of electrons emitted by the outer-MITL cathodes after insulation has been established; (iv) closure of MITL anode-cathode (AK) gaps due to expansion of cathode plasma; (v) energy loss to MITL conductors operated at high lineal current densities; (vi) heating of MITL-anode surfaces due to conduction current and deposition of electron kinetic energy; (vii) negative-space-charge-enhanced ion emission from MITL anode surfaces wherever an anode-surface-temperature threshold has been exceeded; and (viii) closure of MITL AK gaps due to expansion of anode plasma. The circuit model is expected to be most accurate when the fractional current loss is small. We have performed circuit simulations of 52 Z experiments conducted with a variety of accelerator

Transmission-line-circuit model of an 85-TW, 25-MA pulsed-power accelerator

Directory of Open Access Journals (Sweden)

B. T. Hutsel

2018-03-01

Full Text Available We have developed a physics-based transmission-line-circuit model of the Z pulsed-power accelerator. The 33-m-diameter Z machine generates a peak electrical power as high as 85 TW, and delivers as much as 25 MA to a physics load. The circuit model is used to design and analyze experiments conducted on Z. The model consists of 36 networks of transmission-line-circuit elements and resistors that represent each of Zs 36 modules. The model of each module includes a Marx generator, intermediate-energy-storage capacitor, laser-triggered gas switch, pulse-forming line, self-break water switches, and tri-plate transmission lines. The circuit model also includes elements that represent Zs water convolute, vacuum insulator stack, four parallel outer magnetically insulated vacuum transmission lines (MITLs, double-post-hole vacuum convolute, inner vacuum MITL, and physics load. Within the vacuum-transmission-line system the model conducts analytic calculations of current loss. To calculate the loss, the model simulates the following processes: (i electron emission from MITL cathode surfaces wherever an electric-field threshold has been exceeded; (ii electron loss in the MITLs before magnetic insulation has been established; (iii flow of electrons emitted by the outer-MITL cathodes after insulation has been established; (iv closure of MITL anode-cathode (AK gaps due to expansion of cathode plasma; (v energy loss to MITL conductors operated at high lineal current densities; (vi heating of MITL-anode surfaces due to conduction current and deposition of electron kinetic energy; (vii negative-space-charge-enhanced ion emission from MITL anode surfaces wherever an anode-surface-temperature threshold has been exceeded; and (viii closure of MITL AK gaps due to expansion of anode plasma. The circuit model is expected to be most accurate when the fractional current loss is small. We have performed circuit simulations of 52 Z experiments conducted with a

Dynamic modeling of fluid power transmissions for wind turbines

NARCIS (Netherlands)

Diepeveen, N.F.B.; Jarquin Laguna, A.

2011-01-01

Fluid power transmission for wind turbines is quietly gaining more ground/interest. The principle of the various concepts presented so far is to convert aerodynamic torque of the rotor blades into a pressurized fluid flow by means of a positive displacement pump. At the other end of the fluid power

The optimization of wireless power transmission: design and realization.

Science.gov (United States)

Jia, Zhiwei; Yan, Guozheng; Liu, Hua; Wang, Zhiwu; Jiang, Pingping; Shi, Yu

2012-09-01

A wireless power transmission system is regarded as a practical way of solving power-shortage problems in multifunctional active capsule endoscopes. The uniformity of magnetic flux density, frequency stability and orientation stability are used to evaluate power transmission stability, taking into consideration size and safety constraints. Magnetic field safety and temperature rise are also considered. Test benches are designed to measure the relevent parameters. Finally, a mathematical programming model in which these constraints are considered is proposed to improve transmission efficiency. To verify the feasibility of the proposed method, various systems for a wireless active capsule endoscope are designed and evaluated. The optimal power transmission system has the capability to supply continuously at least 500 mW of power with a transmission efficiency of 4.08%. The example validates the feasibility of the proposed method. Introduction of novel designs enables further improvement of this method. Copyright © 2012 John Wiley & Sons, Ltd.

Combination of AC Transmission Expansion Planning and Reactive Power Planning in the restructured power system

International Nuclear Information System (INIS)

Hooshmand, Rahmat-Allah; Hemmati, Reza; Parastegari, Moein

2012-01-01

Highlights: ► To overcome the disadvantages of DC model in Transmission Expansion Planning, AC model should be used. ► The Transmission Expansion Planning associated with Reactive Power Planning results in fewer new transmission lines. ► Electricity market concepts should be considered in Transmission Expansion Planning problem. ► Reliability aspects should be considered in Transmission Expansion Planning problem. ► Particle Swarm Optimization is a suitable optimization method to solve Transmission Expansion Planning problem. - Abstract: Transmission Expansion Planning (TEP) is an important issue in power system studies. It involves decisions on location and number of new transmission lines. Before deregulation of the power system, the goal of TEP problem was investment cost minimization. But in the restructured power system, nodal prices, congestion management, congestion surplus and so on, have been considered too. In this paper, an AC model of TEP problem (AC-TEP) associated with Reactive Power Planning (RPP) is presented. The goals of the proposed planning problem are to minimize investment cost and maximize social benefit at the same time. In the proposed planning problem, in order to improve the reliability of the system the Expected Energy Not Supplied (EENS) index of the system is limited by a constraint. For this purpose, Monte Carlo simulation method is used to determine the EENS. Particle Swarm Optimization (PSO) method is used to solve the proposed planning problem which is a nonlinear mixed integer optimization problem. Simulation results on Garver and RTS systems verify the effectiveness of the proposed planning problem for reduction of the total investment cost, EENS index and also increasing social welfare of the system.

Optimization of output power and transmission efficiency of magnetically coupled resonance wireless power transfer system

Science.gov (United States)

Yan, Rongge; Guo, Xiaoting; Cao, Shaoqing; Zhang, Changgeng

2018-05-01

Magnetically coupled resonance (MCR) wireless power transfer (WPT) system is a promising technology in electric energy transmission. But, if its system parameters are designed unreasonably, output power and transmission efficiency will be low. Therefore, optimized parameters design of MCR WPT has important research value. In the MCR WPT system with designated coil structure, the main parameters affecting output power and transmission efficiency are the distance between the coils, the resonance frequency and the resistance of the load. Based on the established mathematical model and the differential evolution algorithm, the change of output power and transmission efficiency with parameters can be simulated. From the simulation results, it can be seen that output power and transmission efficiency of the two-coil MCR WPT system and four-coil one with designated coil structure are improved. The simulation results confirm the validity of the optimization method for MCR WPT system with designated coil structure.

Peak-load pricing in two-step-modeling of power generation and transmission

International Nuclear Information System (INIS)

Korunig, Jens-Holger

2005-01-01

For the use of electric current transmission and distribution networks, which represent a monopolistic bottleneck, are inevitable. In the context of the liberalization of the current markets vertical separation is possible to create a competitive generator market and separated current transmission and distribution networks, which can made be available to the same conditions to all potential net users. A private, independent network carrier, however, would arrange its net from the interest of profit: He would dimension the net probably smaller and would try to orientate the transmission prices to the actual costs. From the point of view of the system operator as well as from the economic point of view time-dependent transmission prices are preferable at the sight of periodically changing demand. The question, which arises thereby, is, to what extent the property structure affects prices and quantities for the current transmission and which property structure under economical aspects (maximization of the welfare, ...) represents the best. It is to be expected, that with a higher degree of competition a higher efficiency and a larger social welfare are obtained. This is to be analysed in a two-stage model with period-dependent demand and modelling both the power generation and the transmission sector regarding different property structures. Different types of market are assumed both on the production and on the distribution stage. Those market results are examined on their welfare effects. This is to accompany with a realistic modelling above all the network area, which represents further (in contrast to the power generation) a natural monopoly: A natural monopoly has compellingly sub additive cost functions. The net sector (and in a further step also the power generation) is to be modelled with decreasing average and marginal costs (current research task). If one permits each behaviour, an enterprise, which possesses this natural monopoly, will extract monopolist

Transmission probability-based dynamic power control for multi-radio mesh networks

CSIR Research Space (South Africa)

Olwal, TO

2008-09-01

Full Text Available This paper presents an analytical model for the selection of the transmission power based on the bi-directional medium access information. Most of dynamic transmission power control algorithms are based on the single directional channel...

HVDC transmission from isorated nuclear power plant

International Nuclear Information System (INIS)

Takenaka, Kiyoshi; Takasaki, Masahiro; Ichikawa, Tatemi; Hayashi, Toshiyuki

1985-01-01

HVDC transmission directly from nuclear power plant is considered as one of the patterns of long distance and large capacity transmission system. This reports considers two route HVDC transmission from PWR type nuclear power plant, and analyzes dynamic response characteristics due to bus fault, main protection failure and etc. using the AC-DC Power System Simulator. (author)

Performance analysis of a model-sized superconducting DC transmission system based VSC-HVDC transmission technologies using RTDS

International Nuclear Information System (INIS)

Dinh, Minh-Chau; Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon; Yu, In-Keun

2012-01-01

The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail.

Performance analysis of a model-sized superconducting DC transmission system based VSC-HVDC transmission technologies using RTDS

Energy Technology Data Exchange (ETDEWEB)

Dinh, Minh-Chau, E-mail: thanchau7787@gmail.com [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of); Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of); Yu, In-Keun, E-mail: yuik@changwon.ac.kr [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of)

2012-08-15

The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail.

Power transmission charges based on nodal pricing which considers restriction on power transmission; Soden setsuyaku wo koryoshita nodaru pricing ni motozuku soden ryokin

Energy Technology Data Exchange (ETDEWEB)

Okada, K.; Asano, H. [Central Research Institute of Electric Power Industry, Tokyo (Japan); Matsukawa, I. [Musashi University, Tokyo (Japan)

1997-01-30

Power transmission charges were derived by using nodal pricing, and a discussion was given on what effects are given on system conditions, nodal price and consignment charge by how coordination points of independent power producers (IPP) and power demand are handled. A test model having six nodes (busbars) and eleven branches (transmission lines) was used. Since demands of the same kind are hypothesized to be coordinated in this simulation, the total nodal price becomes an equivalent value if there is no restrictions in transmission line current. If the transmission restrictions are taken into consideration, demand amounts at each node are so adjusted that excess current in a transmission line exceeding the transmission capacity will be eliminated. Thus, the demand-supply balancing amount in the entire system becomes smaller than when restrictions are not considered. As a result of the analysis, the IPP coordination points have possibilities to cause congestion (overload current) in the system, raise nodal price at each point, and sharply raise the consignment charge. It was found that an effect may also occur to a node depending on position of demand generation. 6 refs., 3 figs., 7 tabs.

Wireless transmission of power

International Nuclear Information System (INIS)

Grotz, T.

1991-01-01

This paper reports that it has been proven by researchers that electrical energy can be propagated around the world between the surface of the Earth and the ionosphere at extremely low frequencies in what is known as the Schumann Cavity. Experiments to data have shown that electromagnetic waves with frequencies in the range of 8 Hz, the fundamental Schumann Resonance frequency, propagate with litter attenuation around the planet within the Schumann Cavity. It is the intent of this research to determine if the Schumann Cavity can be resonated, if the power that is delivered to the cavity propagated with very low losses, and if power can be extracted at other locations within the cavity. Experimental data collected and calculations made in recent years support the hypothesis that wireless power transmission is a viable and practical alternative to the present systems of power transmission

Calculation and application of energy transaction allocation factors in electric power transmission systems

Science.gov (United States)

Fradi, Aniss

The ability to allocate the active power (MW) loading on transmission lines and transformers, is the basis of the "flow based" transmission allocation system developed by the North American Electric Reliability Council. In such a system, the active power flows must be allocated to each line or transformer in proportion to the active power being transmitted by each transaction imposed on the system. Currently, this is accomplished through the use of the linear Power Transfer Distribution Factors (PTDFs). Unfortunately, no linear allocation models exist for other energy transmission quantities, such as MW and MVAR losses, MVAR and MVA flows, etc. Early allocation schemes were developed to allocate MW losses due to transactions to branches in a transmission system, however they exhibited diminished accuracy, since most of them are based on linear power flow modeling of the transmission system. This thesis presents a new methodology to calculate Energy Transaction Allocation factors (ETA factors, or eta factors), using the well-known process of integration of a first derivative function, as well as consistent and well-established mathematical and AC power flow models. The factors give a highly accurate allocation of any non-linear system quantity to transactions placed on the transmission system. The thesis also extends the new ETA factors calculation procedure to restructure a new economic dispatch scheme where multiple sets of generators are economically dispatched to meet their corresponding load and their share of the losses.

Water-hydraulic power transmission for offshore wind farms

NARCIS (Netherlands)

Diepeveen, N.F.B.; Jarquin Laguna, A.; Kempenaar, A.S.

2012-01-01

The current state of the art of offshore wind turbine power transmission technology is expensive, heavy and maintenance intensive. The Delft Offshore Turbine project considers a radically new concept for power transmission in an offshore wind farm: using seawater as power transmission medium. For

Economy of electric power transmission

International Nuclear Information System (INIS)

Manzoni, G.; Delfanti, M.

2008-01-01

An analysis is presented of the impact of H V and Ehv transmission costs on the final value of the kWh supplied, with reference both to transmission systems of the European type and to long distance point-to-point transmission links. The analysis is extended to A C transmission by underground cables and to Hvdc submarine and aerial links. In the European power system, the impact of transmission costs results to be usually modest, but it may become important in the case of network congestions [it

HVDC transmission from nuclear power plant

International Nuclear Information System (INIS)

Yoshida, Yukio; Takenaka, Kiyoshi; Ichikawa, Takemi; Ueda, Kiyotaka; Machida, Takehiko

1979-01-01

The HVDC transmission directly from nuclear power plants is one of the patterns of long distance and large capacity HVDC transmission systems. In this report, the double pole, two-circuit HVDC transmission from a BWR nuclear power plant is considered, and the dynamic response characteristics due to the faults in dc line and ac line of inverter side are analyzed, to clarify the dynamic characteristics of the BWR nuclear power plant and dc system due to system faults and the effects of dc power control to prevent reactor scram. (1) In the instantaneous earthing fault of one dc line, the reactor is not scrammed by start-up within 0.8 sec. (2) When the earthing fault continues, power transmission drops to 75% by suspending the faulty pole, and the reactor is scrammed. (3) In the instantaneous ground fault of 2 dc lines, the reactor is not scrammed if the faulty dc lines are started up within 0.4 sec. (4) In the existing control of dc lines, the reactor is scrammed when the ac voltage at an ac-dc connection point largely drops due to ac failure. (J.P.N.)

Facts controllers in power transmission and distribution

CERN Document Server

Padiyar, KR

2007-01-01

About the Book: The emerging technology of Flexible AC Transmission System (FACTS) enables planning and operation of power systems at minimum costs, without compromising security. This is based on modern high power electronic systems that provide fast controllability to ensure ''flexible'' operation under changing system conditions. This book presents a comprehensive treatment of the subject by discussing the operating principles, mathematical models, control design and issues that affect the applications. The concepts are explained often with illustrative examples and case studies. In partic

Cost and Benefit Analysis of VSC-HVDC Schemes for Offshore Wind Power Transmission

Institute of Scientific and Technical Information of China (English)

Sheng WANG; Chunmei FENG; An WEN; Jun LIANG

2013-01-01

Due to low load factors of wind power generation,it is possible to reduce transmission capacity to minimize the cost of transmission system construction.Two VSC-HVDC schemes for offshore wind farm,called the point to point (PTP) and DC mesh connections are compared in terms of the utilization of transmission system and its cost.A Weibull distribution is used for estimating offshore wind power generation,besides,the cross correlation between wind farms is considered.The wind energy curtailment is analyzed using the capacity output possibility table (COPT).The system power losses,costs of transmission investment and wind energy curtailment are also computed.A statistic model for the wind generation and transmission is built and simulated in MATLAB to validate the study.It is concluded that a DC mesh transmission can reduce the energy curtailment and power losses.Further benefit is achievable as the wind cross correlation between wind farms decreases.

High Voltage Power Transmission for Wind Energy

Science.gov (United States)

Kim, Young il

The high wind speeds and wide available area at sea have recently increased the interests on offshore wind farms in the U.S.A. As offshore wind farms become larger and are placed further from the shore, the power transmission to the onshore grid becomes a key feature. Power transmission of the offshore wind farm, in which good wind conditions and a larger installation area than an onshore site are available, requires the use of submarine cable systems. Therefore, an underground power cable system requires unique design and installation challenges not found in the overhead power cable environment. This paper presents analysis about the benefit and drawbacks of three different transmission solutions: HVAC, LCC/VSC HVDC in the grid connecting offshore wind farms and also analyzed the electrical characteristics of underground cables. In particular, loss of HV (High Voltage) subsea power of the transmission cables was evaluated by the Brakelmann's theory, taking into account the distributions of current and temperature.

Electrodynamic Wireless Power Transmission to Rotating Magnet Receivers

International Nuclear Information System (INIS)

Garraud, A; Jimenez, J D; Garraud, N; Arnold, D P

2014-01-01

This paper presents an approach for electrodynamic wireless power transmission (EWPT) using a synchronously rotating magnet located in a 3.2 cm 3 receiver. We demonstrate wireless power transmission up to 99 mW (power density equal to 31 mW/cm 3 ) over a 5-cm distance and 5 mW over a 20-cm distance. The maximum operational frequency, and hence maximal output power, is constrained by the magnetic field amplitude. A quadratic relationship is found between the maximal output power and the magnetic field. We also demonstrate simultaneous, power transmission to multiple receivers positioned at different locations

Study for wireless power transmission of nuclear robot system

International Nuclear Information System (INIS)

Kim, Jongseog

2013-01-01

Gasoline engine or electric motor is generally used for driving power of working. Gasoline tank is uncomfortable to carry. Battery capacity does not sustain long time working. Frequent moving back of robot to power charger or refueling tank is inconvenient. Long power cable connection occur winding problem if there are complex structures in walking way. We need some solution for continuous supply of robot energy at the free moving condition of robot. 'Wireless power transmission' is one of the solutions. Some experiment result to transmit wireless power to moving robot is described herein. To find possible wireless power transmission method for nuclear robot, wireless power transmission tests were performed. As result of these tests, it was confirmed that wireless power transmission by using dipole and mat type magnetic induction were possible. As result of flying robot experiment, it was realized that development of light weight core for receiver and wave reflection device for high directional transmitter are necessary for practical use of the dipole type wireless power transmission. Small size core and high directional transmitter will be next target. Mat type wireless power transmission is regarded as useful for robot power charging station in the inside containment

Study for wireless power transmission of nuclear robot system

Energy Technology Data Exchange (ETDEWEB)

Kim, Jongseog [Central Research Institute of Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

2013-05-15

Gasoline engine or electric motor is generally used for driving power of working. Gasoline tank is uncomfortable to carry. Battery capacity does not sustain long time working. Frequent moving back of robot to power charger or refueling tank is inconvenient. Long power cable connection occur winding problem if there are complex structures in walking way. We need some solution for continuous supply of robot energy at the free moving condition of robot. 'Wireless power transmission' is one of the solutions. Some experiment result to transmit wireless power to moving robot is described herein. To find possible wireless power transmission method for nuclear robot, wireless power transmission tests were performed. As result of these tests, it was confirmed that wireless power transmission by using dipole and mat type magnetic induction were possible. As result of flying robot experiment, it was realized that development of light weight core for receiver and wave reflection device for high directional transmitter are necessary for practical use of the dipole type wireless power transmission. Small size core and high directional transmitter will be next target. Mat type wireless power transmission is regarded as useful for robot power charging station in the inside containment.

Electrodynamic wireless power transmission to a torsional receiver

International Nuclear Information System (INIS)

McEachern, K M; Arnold, D P

2013-01-01

This paper presents a wireless power transmission (WPT) concept that uses electrodynamic coupling and torsional motion of a permanent magnet in the receiver. The system is shown to transfer an average power of 3.09 mW (power density equal to 143 μW/cm 3 ) over a distance of 1 cm, an average power of 1.98 mW over a distance of 2 cm, and an average power of 126 μW over a distance of 7 cm. We also demonstrate unaltered power transmission through conductive media, including a human hand and an aluminum plate, highlighting a key advantage of the electrodynamic wireless power transmission approach

Wireless power transmission using ultrasonic guided waves

International Nuclear Information System (INIS)

Kural, A; Pullin, R; Featherston, C; Holford, K; Paget, C

2011-01-01

The unavailability of suitable power supply at desired locations is currently an important obstacle in the development of distributed, wireless sensor networks for applications such as structural health monitoring of aircraft. Proposed solutions range from improved batteries to energy harvesting from vibration, temperature gradients and other sources. A novel approach is being investigated at Cardiff University School of Engineering in cooperation with Airbus. It aims to utilise ultrasonic guided Lamb waves to transmit energy through the aircraft skin. A vibration generator is to be placed in a location where electricity supply is readily available. Ultrasonic waves generated by this device will travel through the aircraft structure to a receiver in a remote wireless sensor node. The receiver will convert the mechanical vibration of the ultrasonic waves back to electricity, which will be used to power the sensor node. This paper describes the measurement and modelling of the interference pattern which emerges when Lamb waves are transmitted continuously as in this power transmission application. The discovered features of the pattern, such as a large signal amplitude variation and a relatively high frequency, are presented and their importance for the development of a power transmission system is discussed.

Wireless power transmission using ultrasonic guided waves

Energy Technology Data Exchange (ETDEWEB)

Kural, A; Pullin, R; Featherston, C; Holford, K [School of Engineering, Cardiff University, Queens Buildings, The Parade, Cardiff CF24 2AA (United Kingdom); Paget, C, E-mail: kurala@cardiff.ac.uk [Airbus Operations Ltd, New Filton Road, BS99 7AR Bristol (United Kingdom)

2011-07-19

The unavailability of suitable power supply at desired locations is currently an important obstacle in the development of distributed, wireless sensor networks for applications such as structural health monitoring of aircraft. Proposed solutions range from improved batteries to energy harvesting from vibration, temperature gradients and other sources. A novel approach is being investigated at Cardiff University School of Engineering in cooperation with Airbus. It aims to utilise ultrasonic guided Lamb waves to transmit energy through the aircraft skin. A vibration generator is to be placed in a location where electricity supply is readily available. Ultrasonic waves generated by this device will travel through the aircraft structure to a receiver in a remote wireless sensor node. The receiver will convert the mechanical vibration of the ultrasonic waves back to electricity, which will be used to power the sensor node. This paper describes the measurement and modelling of the interference pattern which emerges when Lamb waves are transmitted continuously as in this power transmission application. The discovered features of the pattern, such as a large signal amplitude variation and a relatively high frequency, are presented and their importance for the development of a power transmission system is discussed.

Risk Evaluation of a UHV Power Transmission Construction Project Based on a Cloud Model and FCE Method for Sustainability

Directory of Open Access Journals (Sweden)

Huiru Zhao

2015-03-01

Full Text Available In order to achieve the sustainable development of energy, Ultra High Voltage (UHV power transmission construction projects are being established in China currently. Their high-tech nature, the massive amount of money involved, and the need for multi-agent collaboration as well as complex construction environments bring many challenges and risks. Risk management, therefore, is critical to reduce the risks and realize sustainable development of projects. Unfortunately, many traditional risk assessment methods may not perform well due to the great uncertainty and randomness inherent in UHV power construction projects. This paper, therefore, proposes a risk evaluation index system and a hybrid risk evaluation model to evaluate the risk of UHV projects and find out the key risk factors. This model based on a cloud model and fuzzy comprehensive evaluation (FCE method combines the superiority of the cloud model for reflecting randomness and discreteness with the advantages of the fuzzy comprehensive evaluation method in handling uncertain and vague issues. For the sake of proving our framework, an empirical study of “Zhejiang-Fuzhou” UHV power transmission construction project is presented. As key contributions, we find the risk of this project lies at a “middle” to “high” level and closer to a “middle” level; the “management risk” and “social risk” are identified as the most important risk factors requiring more attention; and some risk control recommendations are proposed. This article demonstrates the value of our approach in risk identification, which seeks to improve the risk control level and the sustainable development of UHV power transmission construction projects.

Medium-term electric power demand forecasting based on economic-electricity transmission model

Science.gov (United States)

Li, Wenfeng; Bao, Fangmin; Bai, Hongkun; Liu, Wei; Liu, Yongmin; Mao, Yubin; Wang, Jiangbo; Liu, Junhui

2018-06-01

Electric demand forecasting is a basic work to ensure the safe operation of power system. Based on the theories of experimental economics and econometrics, this paper introduces Prognoz Platform 7.2 intelligent adaptive modeling platform, and constructs the economic electricity transmission model that considers the economic development scenarios and the dynamic adjustment of industrial structure to predict the region's annual electricity demand, and the accurate prediction of the whole society's electricity consumption is realized. Firstly, based on the theories of experimental economics and econometrics, this dissertation attempts to find the economic indicator variables that drive the most economical growth of electricity consumption and availability, and build an annual regional macroeconomic forecast model that takes into account the dynamic adjustment of industrial structure. Secondly, it innovatively put forward the economic electricity directed conduction theory and constructed the economic power transfer function to realize the group forecast of the primary industry + rural residents living electricity consumption, urban residents living electricity, the second industry electricity consumption, the tertiary industry electricity consumption; By comparing with the actual value of economy and electricity in Henan province in 2016, the validity of EETM model is proved, and the electricity consumption of the whole province from 2017 to 2018 is predicted finally.

Maximal network reliability for a stochastic power transmission network

International Nuclear Information System (INIS)

Lin, Yi-Kuei; Yeh, Cheng-Ta

2011-01-01

Many studies regarded a power transmission network as a binary-state network and constructed it with several arcs and vertices to evaluate network reliability. In practice, the power transmission network should be stochastic because each arc (transmission line) combined with several physical lines is multistate. Network reliability is the probability that the network can transmit d units of electric power from a power plant (source) to a high voltage substation at a specific area (sink). This study focuses on searching for the optimal transmission line assignment to the power transmission network such that network reliability is maximized. A genetic algorithm based method integrating the minimal paths and the Recursive Sum of Disjoint Products is developed to solve this assignment problem. A real power transmission network is adopted to demonstrate the computational efficiency of the proposed method while comparing with the random solution generation approach.

Electric Power Transmission Lines

Data.gov (United States)

Department of Homeland Security — Transmission Lines are the system of structures, wires, insulators and associated hardware that carry electric energy from one point to another in an electric power...

Self-tuning wireless power transmission scheme based on on-line scattering parameters measurement and two-side power matching.

Science.gov (United States)

Luo, Yanting; Yang, Yongmin; Chen, Zhongsheng

2014-04-10

Sub-resonances often happen in wireless power transmission (WPT) systems using coupled magnetic resonances (CMR) due to environmental changes, coil movements or component degradations, which is a serious challenge for high efficiency power transmission. Thus self-tuning is very significant to keep WPT systems following strongly magnetic resonant conditions in practice. Traditional coupled-mode ways is difficult to solve this problem. In this paper a two-port power wave model is presented, where power matching and the overall systemic power transmission efficiency are firstly defined by scattering (S) parameters. Then we propose a novel self-tuning scheme based on on-line S parameters measurements and two-side power matching. Experimental results testify the feasibility of the proposed method. These findings suggest that the proposed method is much potential to develop strongly self-adaptive WPT systems with CMR.

Wireless power transmission for battery charging

Science.gov (United States)

Mi, Chris; Li, Siqi; Nguyen, Trong-Duy; Wang, Junhua; Li, Jiangui; Li, Weihan; Xu, Jun

2016-11-15

A wireless power transmission system is provided for high power applications. The power transmission system is comprised generally of a charging unit configured to generate an alternating electromagnetic field and a receive unit configured to receive the alternating electromagnetic field from the charging unit. The charging unit includes a power source; an input rectifier; an inverter; and a transmit coil. The transmit coil has a spirangle arrangement segmented into n coil segments with capacitors interconnecting adjacent coil segments. The receive unit includes a receive coil and an output rectifier. The receive coil also has a spirangle arrangement segmented into m coil segments with capacitors interconnecting adjacent coil segments.

Line Capacity Expansion and Transmission Switching in Power Systems With Large-Scale Wind Power

DEFF Research Database (Denmark)

Villumsen, Jonas Christoffer; Bronmo, Geir; Philpott, Andy B.

2013-01-01

In 2020 electricity production from wind power should constitute nearly 50% of electricity demand in Denmark. In this paper we look at optimal expansion of the transmission network in order to integrate 50% wind power in the system, while minimizing total fixed investment cost and expected cost...... of power generation. We allow for active switching of transmission elements to reduce congestion effects caused by Kirchhoff's voltage law. Results show that actively switching transmission lines may yield a better utilization of transmission networks with large-scale wind power and increase wind power...

Fundamental study of bulk power HVDC transmission

International Nuclear Information System (INIS)

1981-01-01

Study on the HVDC power transmission have been conducted since 1956. Shinshinano-Frequency Changer had been operated at first on 1977, as our home product, and Hokkaido-Honshu DC transmission also realized at 1979. Research and Development of the bulk power HVDC have been promoted by the UHV transmission special committee in our Institute from 1980. This paper is a comprehensive report published in the parts of operating control, insulation of DC line and countermeasure of fault current, and interferences in order to contribute for planning, design and operating of the UHV DC transmission in future. (author)

Revised sequence components power system models for unbalanced power system studies

Energy Technology Data Exchange (ETDEWEB)

Abdel-Akher, M. [Tunku Abdul Rahman Univ., Kuala Lumpur (Malaysia); Nor, K.-M. [Univ. of Technology Malaysia, Johor (Malaysia); Rashid, A.H.A. [Univ. of Malaya, Kuala Lumpur (Malaysia)

2007-07-01

The principle method of analysis using positive, negative, and zero-sequence networks has been used to examine the balanced power system under both balanced and unbalanced loading conditions. The significant advantage of the sequence networks is that the sequence networks become entirely uncoupled in the case of balanced three-phase power systems. The uncoupled sequence networks then can be solved in independent way such as in fault calculation programs. However, the hypothesis of balanced power systems cannot be considered in many cases due to untransposed transmission lines; multiphase line segments in a distribution power system; or transformer phase shifts which cannot be incorporated in the existing models. A revised sequence decoupled power system models for analyzing unbalanced power systems based on symmetrical networks was presented in this paper. These models included synchronous machines, transformers, transmission lines, and voltage regulators. The models were derived from their counterpart's models in phase coordinates frame of reference. In these models, the three sequence networks were fully decoupled with a three-phase coordinates features such as transformer phase shifts and transmission line coupling. The proposed models were used to develop an unbalanced power-flow program for analyzing both balanced and unbalanced networks. The power flow solution was identical to results obtained from a full phase coordinate three-phase power-flow program. 11 refs., 3 tabs.

A cooperative game theory approach to transmission planning in power systems

Science.gov (United States)

Contreras, Javier

The rapid restructuring of the electric power industry from a vertically integrated entity into a decentralized industry has given rise to complex problems. In particular, the transmission component of the electric power system requires new methodologies to fully capture this emerging competitive industry. Game theory models are used to model strategic interactions in a competitive environment. This thesis presents a new decentralized framework to study the transmission network expansion problem using cooperative game theory. First, the players and the rules of the game are defined. Second, a coalition formation scheme is developed. Finally, the optimized cost of expansion is allocated based on the history of the coalition formation.

EHV/HV Underground Cable Systems for Power Transmission

DEFF Research Database (Denmark)

Bak, Claus Leth

of the transmission system must be re‐thought in order to accommodate the transmission needs for the future. New lines have to be constructed. Transmission lines are usually laid out as overhead lines, which are large structures, i.e. a 400 kV power pylon is 50 meters high. According to public opinion, such power...

The effect of electric transmission constraints on how power generation companies bid in the Colombian electrical power market

Directory of Open Access Journals (Sweden)

Luis Eduardo Gallego Vega

2010-05-01

Full Text Available This paper presents the results of research about the effect of transmission constraints on both expected electrical energy to be dispatched and power generation companies’ bidding strategies in the Colombian electrical power market. The proposed model simulates the national transmission grid and economic dispatch by means of optimal power flows. The proposed methodology allows structural problems in the power market to be analyzed due to the exclusive effect of trans- mission constraints and the mixed effect of bidding strategies and transmission networks. A new set of variables is proposed for quantifying the impact of each generation company on system operating costs and the change in expected dispatched energy. A correlation analysis of these new variables is presented, revealing some interesting linearities in some generation companies’ bidding patterns.

Grounding modelling for transient overvoltage simulation in electric power transmission

International Nuclear Information System (INIS)

Moreno O, German; Valencia V, Jaime A; Villada, Fernando

1992-01-01

Grounding plays an important role in transmission line outages and consequently on electric energy transmission quality indexes. Fundamentals of an accurate modelling for transient behaviour analysis, particularly for the response of transmission lines to lightning, are presented. Also, a method to take into account the electromagnetic propagation guided by the grounding electrodes and finally to assess the grounding impedance in order to simulate the transmission line behaviour under lightning is presented. Analysis of impedance behaviour for diverse configurations and simulation results of over voltages on a real 220 kV line are presented to illustrate the capabilities of the method and of the computational program developed

The Evaluation Method of the Lightning Strike on Transmission Lines Aiming at Power Grid Reliability

Science.gov (United States)

Wen, Jianfeng; Wu, Jianwei; Huang, Liandong; Geng, Yinan; Yu, zhanqing

2018-01-01

Lightning protection of power system focuses on reducing the flashover rate, only distinguishing by the voltage level, without considering the functional differences between the transmission lines, and being lack of analysis the effect on the reliability of power grid. This will lead lightning protection design of general transmission lines is surplus but insufficient for key lines. In order to solve this problem, the analysis method of lightning striking on transmission lines for power grid reliability is given. Full wave process theory is used to analyze the lightning back striking; the leader propagation model is used to describe the process of shielding failure of transmission lines. The index of power grid reliability is introduced and the effect of transmission line fault on the reliability of power system is discussed in detail.

Transmission tariffs based on optimal power flow

International Nuclear Information System (INIS)

Wangensteen, Ivar; Gjelsvik, Anders

1998-01-01

This report discusses transmission pricing as a means of obtaining optimal scheduling and dispatch in a power system. This optimality includes consumption as well as generation. The report concentrates on how prices can be used as signals towards operational decisions of market participants (generators, consumers). The main focus is on deregulated systems with open access to the network. The optimal power flow theory, with demand side modelling included, is briefly reviewed. It turns out that the marginal costs obtained from the optimal power flow gives the optimal transmission tariff for the particular load flow in case. There is also a correspondence between losses and optimal prices. Emphasis is on simple examples that demonstrate the connection between optimal power flow results and tariffs. Various cases, such as open access and single owner are discussed. A key result is that the location of the ''marketplace'' in the open access case does not influence the net economical result for any of the parties involved (generators, network owner, consumer). The optimal power flow is instantaneous, and in its standard form cannot deal with energy constrained systems that are coupled in time, such as hydropower systems with reservoirs. A simplified example of how the theory can be extended to such a system is discussed. An example of the influence of security constraints on prices is also given. 4 refs., 24 figs., 7 tabs

Transmission rights and market power on electric power networks. 2. Physical rights

International Nuclear Information System (INIS)

Joskow, Paul; Tirole, Jean

1999-01-01

This discussion paper examines physical transmission rights where the capacity of each potentially congested interface is defined and the rights to use the congested interfaces are created and allocated in some way for suppliers and consumers. The way in which the allocation of physical rights affects competition or increases the buyers or sellers market power in the power generation market when a transmission interface is congested, and how rights markets with different microstructures allocate physical rights and determine rights prices are explored. An electricity market with physical transmission rights in the absence of capacity release rules, and physical transmission rights and market power are addressed. Loop flows, and capacity release rules are discussed. (UK)

Reprint of “Performance analysis of a model-sized superconducting DC transmission system based VSC-HVDC transmission technologies using RTDS”

International Nuclear Information System (INIS)

Dinh, Minh-Chau; Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon; Yu, In-Keun

2013-01-01

Highlights: ► A model-sized superconducting VSC-HVDC system was designed and fabricated. ► A real-time simulation using Real Time Digital Simulator has been performed. ► The AC loss characteristics of HTS DC power cable caused by harmonics were analyzed. ► The AC loss of the HTS DC power cable will be used as a parameter to design the cable cooling system. -- Abstract: The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail

Reprint of “Performance analysis of a model-sized superconducting DC transmission system based VSC-HVDC transmission technologies using RTDS”

Energy Technology Data Exchange (ETDEWEB)

Dinh, Minh-Chau, E-mail: thanchau7787@gmail.com [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of); Ju, Chang-Hyeon; Kim, Sung-Kyu; Kim, Jin-Geun; Park, Minwon [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of); Yu, In-Keun, E-mail: yuik@changwon.ac.kr [Changwon National University, 9 Sarim-Dong, Changwon 641-733 (Korea, Republic of)

2013-01-15

Highlights: ► A model-sized superconducting VSC-HVDC system was designed and fabricated. ► A real-time simulation using Real Time Digital Simulator has been performed. ► The AC loss characteristics of HTS DC power cable caused by harmonics were analyzed. ► The AC loss of the HTS DC power cable will be used as a parameter to design the cable cooling system. -- Abstract: The combination of a high temperature superconducting DC power cable and a voltage source converter based HVDC (VSC-HVDC) creates a new option for transmitting power with multiple collection and distribution points for long distance and bulk power transmissions. It offers some greater advantages compared with HVAC or conventional HVDC transmission systems, and it is well suited for the grid integration of renewable energy sources in existing distribution or transmission systems. For this reason, a superconducting DC transmission system based HVDC transmission technologies is planned to be set up in the Jeju power system, Korea. Before applying this system to a real power system on Jeju Island, system analysis should be performed through a real time test. In this paper, a model-sized superconducting VSC-HVDC system, which consists of a small model-sized VSC-HVDC connected to a 2 m YBCO HTS DC model cable, is implemented. The authors have performed the real-time simulation method that incorporates the model-sized superconducting VSC-HVDC system into the simulated Jeju power system using Real Time Digital Simulator (RTDS). The performance analysis of the superconducting VSC-HVDC systems has been verified by the proposed test platform and the results were discussed in detail.

Active Power Flow Optimization of Industrial Power Supply with Regard to the Transmission Line Conductor Heating

Directory of Open Access Journals (Sweden)

Leyzgold D.Yu.

2015-04-01

Full Text Available This article studies the problem of the transmission line conductor heating effect on the active power flows optimization in the local segment of industrial power supply. The purpose is to determine the optimal generation rating of the distributed power sources, in which the power flow values will correspond to the minimum active power losses in the power supply. The timeliness is the need to define the most appropriate rated power values of distributed sources which will be connected to current industrial power supply. Basing on the model of active power flow optimization, authors formulate the description of the nonlinear transportation problem considering the active power losses depending on the transmission line conductor heating. Authors proposed a new approach to the heating model parameters definition based on allowable current loads and nominal parameters of conductors as part of the optimization problem. Analysis of study results showed that, despite the relatively small active power losses reduction to the tune 0,45% due to accounting of the conductors heating effect for the present configuration of power supply, there are significant fluctuations in the required generation rating in nodes of the network to 9,32% within seasonal changes in the outer air temperature. This fact should be taken into account when selecting the optimum power of distributed generation systems, as exemplified by an arbitrary network configuration.

Analysis of main dynamic parameters of split power transmission

Directory of Open Access Journals (Sweden)

A. Janulevičius

2008-06-01

Full Text Available The review carried out had shown one basic approach of split power transmission to the organization of drive which is applied to stepless transmissions of tractors and parallel hybrid cars. In the split power transmission the power split device uses a planetary gear. Tractor engine power in the split power transmission is transmitted to the drive shaft via a mechanical and hydraulic path. The theoretical analysis of main parameters of the split power transmission of the tractor is presented. The angular velocity of sun and coronary gears of the differential set is estimated by solution of the system of equations in which one equation is made for planetary differential gear, and another – for hydrostatic drive. The analysis of the transmission gear-ratio dependencies on the ratio of hydraulic machines capacities is carried out. Dependence of the variation of angular velocity of the coronary and the sun gears on the ground speed of the tractor is presented. Dependence of sum shaft torque and its constituents, carried by mechanical and hydraulic lines, on sum shaft angular velocity and ground speed of tractor and engine speed is also presented.

High Voltage AC underground cable systems for power transmission

DEFF Research Database (Denmark)

Bak, Claus Leth; Silva, Filipe Miguel Faria da

2016-01-01

researching electrical engineering topics related to using underground cables for power transmission at EHV level and including the 420 kV level. The research topics were laid down by ET/AAU and Energinet.dk in the DANPAC (DANish Power systems with AC Cables) research project. The main topics are discussed...... on the basis of 39 references published by ET/AAU and Energinet.dk. Part I of the paper explains the events that lead to the research project, reactive power compensation, modelling for transient studies, including field measurements and improvements to the existing models, and temporary overvoltages due...... to resonances. Part II covers transient phenomena, harmonics in cables, system modelling for different phenomena, main and backup protections in cable-based networks, online fault detection and future trends....

High Voltage AC underground cable systems for power transmission

DEFF Research Database (Denmark)

Bak, Claus Leth; Silva, Filipe Miguel Faria da

2016-01-01

researching electrical engineering topics related to using underground cables for power transmission at EHV level and including the 420 kV level. The research topics were laid down by ET/AAU and Energinet.dk in the DANPAC (DANish Power systems with Ac Cables) research project. The main topics are discussed...... on the basis of 39 references published by ET/AAU and Energinet.dk. Part I of the paper explains the events that lead to the research project, reactive power compensation, modelling for transient studies, including field measurements and improvements to the existing models, and temporary overvoltages due...... to resonances. Part II covers transient phenomena, harmonics in cables, system modelling for different phenomena, main and backup protections in cable-based networks, online fault detection and future trends....

Optimal Capacity Proportion and Distribution Planning of Wind, Photovoltaic and Hydro Power in Bundled Transmission System

Science.gov (United States)

Ye, X.; Tang, Q.; Li, T.; Wang, Y. L.; Zhang, X.; Ye, S. Y.

2017-05-01

The wind, photovoltaic and hydro power bundled transmission system attends to become common in Northwest and Southwest of China. To make better use of the power complementary characteristic of different power sources, the installed capacity proportion of wind, photovoltaic and hydro power, and their capacity distribution for each integration node is a significant issue to be solved in power system planning stage. An optimal capacity proportion and capacity distribution model for wind, photovoltaic and hydro power bundled transmission system is proposed here, which considers the power out characteristic of power resources with different type and in different area based on real operation data. The transmission capacity limit of power grid is also considered in this paper. Simulation cases are tested referring to one real regional system in Southwest China for planning level year 2020. The results verify the effectiveness of the model in this paper.

Study on frequency characteristics of wireless power transmission system based on magnetic coupling resonance

Science.gov (United States)

Liang, L. H.; Liu, Z. Z.; Hou, Y. J.; Zeng, H.; Yue, Z. K.; Cui, S.

2017-11-01

In order to study the frequency characteristics of the wireless energy transmission system based on the magnetic coupling resonance, a circuit model based on the magnetic coupling resonant wireless energy transmission system is established. The influence of the load on the frequency characteristics of the wireless power transmission system is analysed. The circuit coupling theory is used to derive the minimum load required to suppress frequency splitting. Simulation and experimental results verify that when the load size is lower than a certain value, the system will appear frequency splitting, increasing the load size can effectively suppress the frequency splitting phenomenon. The power regulation scheme of the wireless charging system based on magnetic coupling resonance is given. This study provides a theoretical basis for load selection and power regulation of wireless power transmission systems.

4th International Conference on Power Transmissions

CERN Document Server

2013-01-01

This books contains the Proceedings of the 4th International Conference on Power Transmissions, that was held in Sinaia, Romania from June 20 -23, 2012. Power Transmissions is a very complex and multi-disciplinary scientific field of Mechanical Engineering that covers the different types of transmissions (mechanical, hydraulic, pneumatic) as well as all the machine elements involved, such as gears, bearings, shafts, couplings and a lot more. It concerns not only their basic theory but also their design, analysis, testing, application and maintenance. The requirements set to modern power transmissions are really tough to meet: They need to be more efficient, stronger, smaller, noiseless, easier to produce and to cost less. There is a strong demand to become easier in operation and maintenance, or even automatic and in maintenance-free. Last but not least, they should be easily recycled and respect the environment. Joint efforts of specialists from both academia and industry can significantly contribute to fulf...

Novel approach to assess local market power considering transmission constraints

International Nuclear Information System (INIS)

Li, Canbing; Xia, Qing; Kang, Chongqing; Jiang, Jianjian

2008-01-01

Market power (MP) assessment and mitigation affect the efficiency of the generation market. The traditional indices such as HHI and Lerner index can not express local market power, which caused by transmission constraints. Transmission constraints divide the market into some smaller parts. Some generators can abuse their MP in one part but not in the whole market. This paper describes a new approach to assess market power. The main contributions of the new method can be summarized as following. First, the concept of local market is developed, and the whole power system is divided into several local markets, as transmission congestions dividing the market. In the local markets, there are no transmission constraints so local market power does not exist. Then the local market power index (LMPI) is calculated according to market concentration, transmission constraints, and demand-supply ratio. Based on LMPI, the integrated local market power index which describes the whole picture of market can be obtained. It has been proved that the new approach can assess market power exactly, and identify the critical factor that results in market power and where generators are easy to exercise market power. The finding in this paper is helpful for market monitoring and mitigating market power. Moreover, the new index can be used to evaluate the power grid availability to generation competition and the power transmission expansion planning. (author)

Power Transmission by Optical Fibers for Component Inherent Communication

Directory of Open Access Journals (Sweden)

Michael Dumke

2010-02-01

Full Text Available The use of optical fibers for power transmission has been investigated intensely. An optically powered device combined with optical data transfer offers several advantages compared to systems using electrical connections. Optical transmission systems consist of a light source, a transmission medium and a light receiver. The overall system performance depends on the efficiency of opto-electronic converter devices, temperature and illumination dependent losses, attenuation of the transmission medium and coupling between transmitter and fiber. This paper will summarize the state of the art for optically powered systems and will discuss reasons for negative influences on efficiency. Furthermore, an outlook on power transmission by the use of a new technology for creating polymer optical fibers (POF via micro dispensing will be given. This technology is capable to decrease coupling losses by direct contacting of opto-electronic devices.

Transmission rights and market power

International Nuclear Information System (INIS)

Bushnell, J.

1999-01-01

Most of the concerns about physical transmission rights relate to the ability to implicitly or explicitly remove that transmission capacity from the market-place. Under a very strict form of physical right, owners could simply choose not to sell it if they don't want to use it. Modifications that require the release of spare capacity back into an open market could potentially alleviate this problem but there is concern that such releases would not occur far enough in advance to be of much use to schedulers. Similarly, the transmission capacity that is made available for use by non-rights holders can also be manipulated by the owners of transmission rights. The alternative form, financial transmission rights, provide to their owners congestion payments, but physical control of transmission paths. In electricity markets such as California's, even financial transmission rights could potentially be utilized to effectively withhold transmission capacity from the marketplace. However, methods for withholding transmission capacity are somewhat more convoluted, and probably more difficult, for owners of financial rights than for owners of physical rights. In this article, the author discusses some of the potential concerns over transmission rights and their use for the exercise of various forms of market power

Transmission Power Control for Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Kuo-Hsien Hsia

2017-02-01

Full Text Available Wireless sensor networks can be widely applied for a security system or a smart home system. Since some of the wireless remote sensor nodes may be powered by energy storage devices such as batteries, it is a very important issue to transmit signals at lower power with the consideration of the communication effectiveness. In this paper, we will provide a fuzzy controller with two inputs and one output for received signal strength indicator (RSSI and link quality indicator (LQI to adjust transmission power suitably in order to maintaining a certain communication level with a reduced energy consumption. And we will divide the sampling period of a sensor node into four intervals so that the sensor node radio device does not in receiving or transmission status all the time. Hence the sensor node can adjust transmission power automatically and reduce sensor node power consumption. Experimental results show that the battery life can be extended to about 10 times for the designed sensor node comparing to a normal node.

Simulation Analysis of Wireless Power Transmission System for Biomedical Applications

Science.gov (United States)

Yang, Zhao; Wei, Zhiqiang; Chi, Haokun; Yin, Bo; Cong, Yanping

2018-03-01

In recent years, more and more implantable medical devices have been used in the medical field. Some of these devices, such as brain pacemakers, require long-term power support. The WPT(wireless power transmission) technology which is more convenient and economical than replacing the battery by surgery, has become the first choice of many patients. In this paper, we design a WPT system that can be used in implantable medical devices, simulate the transmission efficiency of the system in the air and in the head model, and simulate the SAR value when the system working in the head model. The results show that when implantation depth of the secondary coil is 3 mm, the efficiency of the system can reach 45%, and the maximum average SAR value is 2.19 W / kg, slightly higher than the standard of IEEE.

Microwave power - An energy transmission alternative for the year 2000

Science.gov (United States)

Nalos, E.; Sperber, R.

1980-01-01

Recent technological advances related to the feasibility of efficient RF-dc rectification make it likely that by the year 2000 the transmission of power through space will have become a practical reality. Proposals have been made to power helicopters, aircraft, balloons, and rockets remotely. Other proposals consider the transfer of power from point to point on earth via relay through space or a transmission of power from large power sources in space. Attention has also been given to possibilities regarding the transmission of power between various points in the solar system. An outline is provided of the microwave power transmission system envisaged for the solar power satellite, taking into account the transmitting antenna, the receiver on earth, aspects of beam formation and control, transmitter options, the receiving antenna design, and cost and efficiency considerations.

Financial transmission rights meet Cournot: How TCCs curb market power

International Nuclear Information System (INIS)

Stoft, S.

1999-01-01

This paper reconsiders the problem of market power when generators face a demand curve limited by a transmission constraint. After demonstrating that the problem's importance originates in an inherent ambiguity in Cournot-Nash theory, the author reviews Oren's argument that generators in this situation capture all congestion rents. In the one-line case, this argument depends on an untested hypothesis while in the three-line case, the Nash equilibrium was misidentified. Finally, the argument that financial transmission rights (and TCCs in particular) will have zero market value is refuted by modeling the possibility of their purchase by generators. This allows transmission owners, who initially own the TCCs, to capture some of the congestion rent. In fact when total capacity exceeds line capacity by more than the capacity of the largest generator, TCCs should attain their perfectly competitive value, thereby curbing the market power of generators

Integrated multiperiod power generation and transmission expansion planning with sustainability aspects in a stochastic environment

International Nuclear Information System (INIS)

Seddighi, Amir Hossein; Ahmadi-Javid, Amir

2015-01-01

This paper presents a multistage stochastic programming model to address sustainable power generation and transmission expansion planning. The model incorporates uncertainties about future electricity demand, fuel prices, greenhouse gas emissions, as well as possible disruptions to which the power system is subject. A number of sustainability regulations and policies are considered to establish a framework for the social responsibility of the power system. The proposed model is applied to a real-world case, and several sensitivity analyses are carried out to provide managerial insights into different aspects of the model. The results emphasize the important role played by sustainability policies on the configuration of the power grid. - Highlights: • This paper considers integrated power generation and transmission expansion planning. • Sustainability aspects are incorporated into a multiperiod stochastic setting. • A stochastic mathematical programming model is developed to address the problem. • The model is applied to a real-world case and numerical studies are carried out

Optimal Operation of Energy Storage in Power Transmission and Distribution

Science.gov (United States)

Akhavan Hejazi, Seyed Hossein

In this thesis, we investigate optimal operation of energy storage units in power transmission and distribution grids. At transmission level, we investigate the problem where an investor-owned independently-operated energy storage system seeks to offer energy and ancillary services in the day-ahead and real-time markets. We specifically consider the case where a significant portion of the power generated in the grid is from renewable energy resources and there exists significant uncertainty in system operation. In this regard, we formulate a stochastic programming framework to choose optimal energy and reserve bids for the storage units that takes into account the fluctuating nature of the market prices due to the randomness in the renewable power generation availability. At distribution level, we develop a comprehensive data set to model various stochastic factors on power distribution networks, with focus on networks that have high penetration of electric vehicle charging load and distributed renewable generation. Furthermore, we develop a data-driven stochastic model for energy storage operation at distribution level, where the distribution of nodal voltage and line power flow are modelled as stochastic functions of the energy storage unit's charge and discharge schedules. In particular, we develop new closed-form stochastic models for such key operational parameters in the system. Our approach is analytical and allows formulating tractable optimization problems. Yet, it does not involve any restricting assumption on the distribution of random parameters, hence, it results in accurate modeling of uncertainties. By considering the specific characteristics of random variables, such as their statistical dependencies and often irregularly-shaped probability distributions, we propose a non-parametric chance-constrained optimization approach to operate and plan energy storage units in power distribution girds. In the proposed stochastic optimization, we consider

Through-Metal-Wall Power Delivery and Data Transmission for Enclosed Sensors: A Review

Directory of Open Access Journals (Sweden)

Ding-Xin Yang

2015-12-01

Full Text Available The aim of this review was to assess the current viable technologies for wireless power delivery and data transmission through metal barriers. Using such technologies sensors enclosed in hermetical metal containers can be powered and communicate through exterior power sources without penetration of the metal wall for wire feed-throughs. In this review, we first discuss the significant and essential requirements for through-metal-wall power delivery and data transmission and then we: (1 describe three electromagnetic coupling based techniques reported in the literature, which include inductive coupling, capacitive coupling, and magnetic resonance coupling; (2 present a detailed review of wireless ultrasonic through-metal-wall power delivery and/or data transmission methods; (3 compare various ultrasonic through-metal-wall systems in modeling, transducer configuration and communication mode with sensors; (4 summarize the characteristics of electromagnetic-based and ultrasound-based systems, evaluate the challenges and development trends. We conclude that electromagnetic coupling methods are suitable for through thin non-ferromagnetic metal wall power delivery and data transmission at a relatively low data rate; piezoelectric transducer-based ultrasonic systems are particularly advantageous in achieving high power transfer efficiency and high data rates; the combination of more than one single technique may provide a more practical and reliable solution for long term operation.

Matching problems in pulse power radial transmission lines

International Nuclear Information System (INIS)

Mittag, K.; Brandelik, A.

1984-12-01

In this report we study the power transfer from a generator along a coaxial transmission line followed by a radial transmission line into a load, which in our application is a pseudo-spark plasma of about one millimeter diameter and about 15 cm in length. First the theoretical background based on transmission line theory is described. Then numerical results are presented. The main conclusion is that when matching the pulse power generator to the pseudo-spark plasma, the effect of the impedance transformation caused by the radial transmission line has to be taken into account. The conditions to obtain an optimal match are described. (orig.) [de

Feasibility study of wireless power transmission systems

Science.gov (United States)

Robinson, W. J., Jr.

1968-01-01

Wireless microwave or laser energy transfers power from a manned earth-orbiting central station to unmanned astronomical substations. More efficient systems are required for the microwave power transmission.

Scenarios of power transmission networks; Cenarios de redes de transmissao de energia eletrica

Energy Technology Data Exchange (ETDEWEB)

Souza Fonseca, L.G. de; Savi, T C.O.; Morozowski Filho, M; Camargo, C C [ELETROSUL, Florianopolis, SC (Brazil)

1985-12-31

This work discusses the electrical network expansion considering long term horizons and a purpose of methodology for the establishment of transmission network scenarios. As part of the transmission scenario studies the network expansion problem is described by linearized power flow models and, for transmission system analysis and synthesis, the minimum effort criteria and interactive SINTRA program are used. 4 refs., 3 figs., 2 tabs.

Environmental impacts of power plants and transmission lines in power system planning

International Nuclear Information System (INIS)

Miracapillo, C.; Moreschini, G.; Rome Univ. 'La Sapienza'

1992-01-01

This paper deals with a criterion to assess the environmental impacts of power plants and transmission lines in power system planning. First, the effects of hydro-plants, thermal plants and transmission lines are reviewed. Then, a number of methods for the evaluation of the environmental impacts of civil and industrial plants are described. A new criterion is proposed to introduce the evaluation of the environmental impact and related costs into methods for power system planning. Finally, the criterion is applied to a simple case

Microwave power engineering generation, transmission, rectification

CERN Document Server

Okress, Ernest C

1968-01-01

Microwave Power Engineering, Volume 1: Generation, Transmission, Rectification considers the components, systems, and applications and the prevailing limitations of the microwave power technology. This book contains four chapters and begins with an introduction to the basic concept and developments of microwave power technology. The second chapter deals with the development of the main classes of high-power microwave and optical frequency power generators, such as magnetrons, crossed-field amplifiers, klystrons, beam plasma amplifiers, crossed-field noise sources, triodes, lasers. The third

Data driven transmission power control for wireless sensor networks

NARCIS (Netherlands)

kotian, Roshan; Exarchakos, Georgios; Liotta, Antonio; Di Fatta, G.; Fortino, G.; Li, W.; Pathan, M.; Stahl, F.; Guerrieri, A.

2015-01-01

Transmission Power Control (TPC) is employed in the sensor nodes with the main objective of minimizing transmission power consumption. However, major drawbacks with well-known TPC are time consuming and energy inefficient initialization phase. Moreover, they employ Received Signal Strength Indicator

Eco-design of power transmissions systems

International Nuclear Information System (INIS)

Wang, W.

2011-01-01

The demand to preserve the environment and form a sustainable development is greatly increasing in the recent decades all over the world, and this environmental concern is also merged in electrical power industry, resulting in many eco-design approaches in Transmission and Distribution (T and D) industries. As a method of eco-design, Life Cycle Assessment (LCA) is a systematic tool that enables the assessment of the environmental impacts of a product or service throughout its entire life cycle, i.e. raw material production, manufacture, distribution, use and disposal including all intervening transportation steps necessary or caused by the product's existence. In T and D industries, LCA has been done for a lot of products individually, in order to see one product's environmental impacts and to seek for ways of improving its environmental performance. This eco-design for product approach is a rather well-developed trend, however, as only a single electrical product cannot provide the electrical power to users, electrical system consists of a huge number of components, in order to investigate system's environmental profile, the entire environmental profiles of different composing products has to be integrated systematically, that is to say, a system approach is needed. Under this philosophy, the study 'Eco-design of Power Transmission Systems' is conducted in this thesis, with the purpose of analysing the transmission systems' environmental impacts, locating the major environmental burden sources of transmission systems, selecting and/or developing methodologies of reducing its environmental impacts. (author)

A Case Study of Wind-PV-Thermal-Bundled AC/DC Power Transmission from a Weak AC Network

Science.gov (United States)

Xiao, H. W.; Du, W. J.; Wang, H. F.; Song, Y. T.; Wang, Q.; Ding, J.; Chen, D. Z.; Wei, W.

2017-05-01

Wind power generation and photovoltaic (PV) power generation bundled with the support by conventional thermal generation enables the generation controllable and more suitable for being sent over to remote load centre which are beneficial for the stability of weak sending end systems. Meanwhile, HVDC for long-distance power transmission is of many significant technique advantages. Hence the effects of wind-PV-thermal-bundled power transmission by AC/DC on power system have become an actively pursued research subject recently. Firstly, this paper introduces the technical merits and difficulties of wind-photovoltaic-thermal bundled power transmission by AC/DC systems in terms of meeting the requirement of large-scale renewable power transmission. Secondly, a system model which contains a weak wind-PV-thermal-bundled sending end system and a receiving end system in together with a parallel AC/DC interconnection transmission system is established. Finally, the significant impacts of several factors which includes the power transmission ratio between the DC and AC line, the distance between the sending end system and receiving end system, the penetration rate of wind power and the sending end system structure on system stability are studied.

Watt-level wireless power transmission to multiple compact receivers

International Nuclear Information System (INIS)

Garraud, A; Munzer, D J; Althar, M; Garraud, N; Arnold, D P

2015-01-01

This paper reports an electrodynamic wireless power transmission (EWPT) system using a low-frequency (300 Hz) magnetic field to transmit watt-scale power levels to multiple compact receivers. As compared to inductively or resonantly coupled coils, EWPT facilitates transmission to multiple non-interacting receivers with little restriction on their orientation. A single 3.0 cm 3 receiver achieves 1.25 W power transmission with 8% efficiency at a distance of 1 cm (350 mW/cm 3 power density) from the transmitter. The same prototype achieves 9 mW at a distance of 9 cm. Moreover, we demonstrate simultaneous recharge of two wearable devices, using two receivers located in arbitrary positions and orientations. (paper)

HVDC power transmission technology assessment

Energy Technology Data Exchange (ETDEWEB)

Hauth, R.L.; Tatro, P.J.; Railing, B.D. [New England Power Service Co., Westborough, MA (United States); Johnson, B.K.; Stewart, J.R. [Power Technologies, Inc., Schenectady, NY (United States); Fink, J.L.

1997-04-01

The purpose of this study was to develop an assessment of the national utility system`s needs for electric transmission during the period 1995-2020 that could be met by future reduced-cost HVDC systems. The assessment was to include an economic evaluation of HVDC as a means for meeting those needs as well as a comparison with competing technologies such as ac transmission with and without Flexible AC Transmission System (FACTS) controllers. The role of force commutated dc converters was to be assumed where appropriate. The assessment begins by identifying the general needs for transmission in the U.S. in the context of a future deregulated power industry. The possible roles for direct current transmission are then postulated in terms of representative scenarios. A few of the scenarios are illustrated with the help of actual U.S. system examples. non-traditional applications as well as traditional applications such as long lines and asynchronous interconnections are discussed. The classical ``break-even distance`` concept for comparing HVDC and ac lines is used to assess the selected scenarios. The impact of reduced-cost converters is reflected in terms of the break-even distance. This report presents a comprehensive review of the functional benefits of HVDC transmission and updated cost data for both ac and dc system components. It also provides some provocative thoughts on how direct current transmission might be applied to better utilize and expand our nation`s increasingly stressed transmission assets.

Power Transmission Scheduling for Generators in a Deregulated Environment Based on a Game-Theoretic Approach

Directory of Open Access Journals (Sweden)

Bingtuan Gao

2015-12-01

Full Text Available In a deregulated environment of the power market, in order to lower their energy price and guarantee the stability of the power network, appropriate transmission lines have to be considered for electricity generators to sell their energy to the end users. This paper proposes a game-theoretic power transmission scheduling for multiple generators to lower their wheeling cost. Based on the embedded cost method, a wheeling cost model consisting of congestion cost, cost of losses and cost of transmission capacity is presented. By assuming each generator behaves in a selfish and rational way, the competition among the multiple generators is formulated as a non-cooperative game, where the players are the generators and the strategies are their daily schedules of power transmission. We will prove that there exists at least one pure-strategy Nash equilibrium of the formulated power transmission game. Moreover, a distributed algorithm will be provided to realize the optimization in terms of minimizing the wheeling cost. Finally, simulations were performed and discussed to verify the feasibility and effectiveness of the proposed non-cooperative game approach for the generators in a deregulated environment.

Shifting and power sharing control of a novel dual input clutchless transmission for electric vehicles

Science.gov (United States)

Liang, Jiejunyi; Yang, Haitao; Wu, Jinglai; Zhang, Nong; Walker, Paul D.

2018-05-01

To improve the overall efficiency of electric vehicles and guarantee the driving comfort and vehicle drivability under the concept of simplifying mechanism complexity and minimizing manufacturing cost, this paper proposes a novel clutchless power-shifting transmission system with shifting control strategy and power sharing control strategy. The proposed shifting strategy takes advantage of the transmission architecture to achieve power-on shifting, which greatly improves the driving comfort compared with conventional automated manual transmission, with a bump function based shifting control method. To maximize the overall efficiency, a real-time power sharing control strategy is designed to solve the power distribution problem between the two motors. Detailed mathematical model is built to verify the effectiveness of the proposed methods. The results demonstrate the proposed strategies considerably improve the overall efficiency while achieve non-interrupted power-on shifting and maintain the vehicle jerk during shifting under an acceptable threshold.

Location of Faults in Power Transmission Lines Using the ARIMA Method

Directory of Open Access Journals (Sweden)

Danilo Pinto Moreira de Souza

2017-10-01

Full Text Available One of the major problems in transmission lines is the occurrence of failures that affect the quality of the electric power supplied, as the exact localization of the fault must be known for correction. In order to streamline the work of maintenance teams and standardize services, this paper proposes a method of locating faults in power transmission lines by analyzing the voltage oscillographic signals extracted at the line monitoring terminals. The developed method relates time series models obtained specifically for each failure pattern. The parameters of the autoregressive integrated moving average (ARIMA model are estimated in order to adjust the voltage curves and calculate the distance from the initial fault localization to the terminals. Simulations of the failures are performed through the ATPDraw ® (5.5 software and the analyses were completed using the RStudio ® (1.0.143 software. The results obtained with respect to the failures, which did not involve earth return, were satisfactory when compared with widely used techniques in the literature, particularly when the fault distance became larger in relation to the beginning of the transmission line.

Induction of Inflammation In Vivo by Electrocardiogram Sensor Operation Using Wireless Power Transmission.

Science.gov (United States)

Heo, Jin-Chul; Kim, Beomjoon; Kim, Yoon-Nyun; Kim, Dae-Kwang; Lee, Jong-Ha

2017-12-14

Prolonged monitoring by cardiac electrocardiogram (ECG) sensors is useful for patients with emergency heart conditions. However, implant monitoring systems are limited by lack of tissue biocompatibility. Here, we developed an implantable ECG sensor for real-time monitoring of ventricular fibrillation and evaluated its biocompatibility using an animal model. The implantable sensor comprised transplant sensors with two electrodes, a wireless power transmission system, and a monitoring system. The sensor was inserted into the subcutaneous tissue of the abdominal area and operated for 1 h/day for 5 days using a wireless power system. Importantly, the sensor was encapsulated by subcutaneous tissue and induced angiogenesis, inflammation, and phagocytosis. In addition, we observed that the levels of inflammation-related markers increased with wireless-powered transmission via the ECG sensor; in particular, levels of the Th-1 cytokine interleukin-12 were significantly increased. The results showed that induced tissue damage was associated with the use of wireless-powered sensors. We also investigated research strategies for the prevention of adverse effects caused by lack of tissue biocompatibility of a wireless-powered ECG monitoring system and provided information on the clinical applications of inflammatory reactions in implant treatment using the wireless-powered transmission system.

Integration of wind power in Germany's transmission grid by using HVDC links

Energy Technology Data Exchange (ETDEWEB)

Wasserrab, Andreas; Fleckenstein, Marco; Balzer, Gerd [Technische Univ. Darmstadt (Germany). Inst. of Electrical Power and Energy

2012-07-01

This paper deals with the challenges for the integration of wind power in Germany's transmission grid. Several options for the expansion of transmission grids are discussed. The consideration focuses on HVDC technologies, which are used for further analyses. The basis of the analysis is the transmission grid of a German transmission system operator, which is implemented in a simulation tool. The model consists of the 110-kV-, 220-kV- and the 380-kV-system. In different scenarios the integration of wind power is analysed by applying HVDC links to connect the northern part of the grid with the load centres in the South. The results of load flow calculations are discussed focusing on transmission line loading and voltage stability. The paper concludes with future prospects of HVDC applications in Germany. (orig.)

Recurrent-neural-network-based identification of a cascade hydraulic actuator for closed-loop automotive power transmission control

International Nuclear Information System (INIS)

You, Seung Han; Hahn, Jin Oh

2012-01-01

By virtue of its ease of operation compared with its conventional manual counterpart, automatic transmissions are commonly used as automotive power transmission control system in today's passenger cars. In accordance with this trend, research efforts on closed-loop automatic transmission controls have been extensively carried out to improve ride quality and fuel economy. State-of-the-art power transmission control algorithms may have limitations in performance because they rely on the steady-state characteristics of the hydraulic actuator rather than fully exploit its dynamic characteristics. Since the ultimate viability of closed-loop power transmission control is dominated by precise pressure control at the level of hydraulic actuator, closed-loop control can potentially attain superior efficacy in case the hydraulic actuator can be easily incorporated into model-based observer/controller design. In this paper, we propose to use a recurrent neural network (RNN) to establish a nonlinear empirical model of a cascade hydraulic actuator in a passenger car automatic transmission, which has potential to be easily incorporated in designing observers and controllers. Experimental analysis is performed to grasp key system characteristics, based on which a nonlinear system identification procedure is carried out. Extensive experimental validation of the established model suggests that it has superb one-step-ahead prediction capability over appropriate frequency range, making it an attractive approach for model-based observer/controller design applications in automotive systems

The electric power engineering handbook electric power generation, transmission, and distribution

CERN Document Server

Grigsby, Leonard L

2012-01-01

Featuring contributions from worldwide leaders in the field, the carefully crafted Electric Power Generation, Transmission, and Distribution, Third Edition (part of the five-volume set, The Electric Power Engineering Handbook) provides convenient access to detailed information on a diverse array of power engineering topics. Updates to nearly every chapter keep this book at the forefront of developments in modern power systems, reflecting international standards, practices, and technologies. Topics covered include: * Electric Power Generation: Nonconventional Methods * Electric Power Generation

Microwave energy transmission system for solar power station

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, Hiroshi

1988-05-05

This paper deals with a microwave wireless energy transmission system which will be required for a solar power station under investigation, particularly, it describes its foundation and future investigation. It is supposed that for realization of microwave wireless transmission techniques, it is most important to investigate the effect of strong microwave beams on a plasma environment, establish control techniques for microwave beams in which a retro-directive system is combined with a computer control system, and develop a semiconductor transmission module. Institute of Space and Astronautical Science (Japan) made an experiment on the effect of microwaves on ionospheric plasma by using an observatory rocket. The institute has planned to make an experiment on a microwave energy transmission system which is to be mounted to a small-scale space flyer unit in order to examine the control of microwave beams and 10 KW power transmission, in addition to investigation on the interaction of microwave energy beams with a plasma environment. (4 figs, 3 tabs, 20 refs)

Impedance matching wireless power transmission system for biomedical devices.

Science.gov (United States)

Lum, Kin Yun; Lindén, Maria; Tan, Tian Swee

2015-01-01

For medical application, the efficiency and transmission distance of the wireless power transfer (WPT) are always the main concern. Research has been showing that the impedance matching is one of the critical factors for dealing with the problem. However, there is not much work performed taking both the source and load sides into consideration. Both sides matching is crucial in achieving an optimum overall performance, and the present work proposes a circuit model analysis for design and implementation. The proposed technique was validated against experiment and software simulation. Result was showing an improvement in transmission distance up to 6 times, and efficiency at this transmission distance had been improved up to 7 times as compared to the impedance mismatch system. The system had demonstrated a near-constant transfer efficiency for an operating range of 2cm-12cm.

Phased Array Excitations For Efficient Near Field Wireless Power Transmission

Science.gov (United States)

2016-09-01

channeled to the battery or power plant. Figure 2. WPT System Block Diagram for Battery Charging. Source : [2]. Wireless power transfer has gained...EXCITATIONS FOR EFFICIENT NEAR-FIELD WIRELESS POWER TRANSMISSION by Sean X. Hong September 2016 Thesis Advisor: David Jenn Second Reader...TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE PHASED ARRAY EXCITATIONS FOR EFFICIENT NEAR-FIELD WIRELESS POWER TRANSMISSION 5

Transmission cost allocation based on power flow tracing considering reliability benefit

International Nuclear Information System (INIS)

Leepreechanon, N.; Singharerg, S.; Padungwech, W.; Nakawiro, W.; Eua-Arporn, B.; David, A.K.

2007-01-01

Power transmission networks must be able to accommodate the continuously growing demand for reliable and economical electricity. This paper presented a method to allocate transmission use and reliability cost to both generators and end-consumers. Although transmission cost allocation methods change depending on the local context of the electric power industry, there is a common principle that transmission line capacity should be properly allocated to accommodate actual power delivery with an adequate reliability margin. The method proposed in this paper allocates transmission embedded cost to both generators and loads in an equitable manner, incorporating probability indices to allocate transmission reliability margin among users in both supply and demand sides. The application of the proposed method was illustrated using Bialek's tracing method on a multiple-circuit, six-bus transmission system. Probabilistic indices known as the transmission internal reliability margin (TIRM) and transmission external reliability margin (TERM) decomposed from the transmission reliability margin (TRM) were introduced, making true cost of using overall transmission facilities. 6 refs., 11 tabs., 5 figs

Wireless electricity (Power) transmission using solar based power satellite technology

International Nuclear Information System (INIS)

Maqsood, M; Nasir, M Nauman

2013-01-01

In the near future due to extensive use of energy, limited supply of resources and the pollution in environment from present resources e.g. (wood, coal, fossil fuel) etc, alternative sources of energy and new ways to generate energy which are efficient, cost effective and produce minimum losses are of great concern. Wireless electricity (Power) transmission (WET) has become a focal point as research point of view and nowadays lies at top 10 future hot burning technologies that are under research these days. In this paper, we present the concept of transmitting power wirelessly to reduce transmission and distribution losses. The wired distribution losses are 70 – 75% efficient. We cannot imagine the world without electric power which is efficient, cost effective and produce minimum losses is of great concern. This paper tells us the benefits of using WET technology specially by using Solar based Power satellites (SBPS) and also focuses that how we make electric system cost effective, optimized and well organized. Moreover, attempts are made to highlight future issues so as to index some emerging solutions.

[Design and optimization of wireless power and data transmission for visual prosthesis].

Science.gov (United States)

Lei, Xuping; Wu, Kaijie; Zhao, Lei; Chai, Xinyu

2013-11-01

Boosting spatial resolution of visual prostheses is an effective method to improve implant subjects' visual perception. However, power consumption of visual implants greatly rises with the increasing number of implanted electrodes. In respond to this trend, visual prostheses need to develop high-efficiency wireless power transmission and high-speed data transmission. This paper presents a review of current research progress on wireless power and data transmission for visual prostheses, analyzes relative principles and requirement, and introduces design methods of power and data transmission.

The Government Incentive Regulation Model and Pricing Mechanism in Power Transmission and Distribution Market

Directory of Open Access Journals (Sweden)

Huan Zhang

2016-01-01

Full Text Available The power transmission and distribution (T&D market’s natural monopoly and individual information have been the impediment to improving the energy efficiency in the whole T&D market. In order to improve the whole social welfare, T&D market should be controlled by government. An incentive regulation model with the target of maximizing social welfare has been studied. A list of contracts with transferring payment and quantity of T&D are given to motivate the corporation to reveal the true technical parameter and input the optimal investment. The corporate revenue, optimal investment, and effort are proved to depend on its own technical parameter. The part of incentive regulation model ends with the optimal pricing mechanism of T&D market. At the end of this paper, we give a numerical example to explain our research and confirm its function graphically.

Equivalent circuit modeling of space charge dominated magnetically insulated transmission lines

Energy Technology Data Exchange (ETDEWEB)

Hiraoka, Kazuki; Nakajima, Mitsuo; Horioka, Kazuhiko

1997-12-31

A new equivalent circuit model for space charge dominated MITLs (Magnetically Insulated Transmission Lines) was developed. MITLs under high power operation are dominated with space charge current flowing between anode and cathode. Conventional equivalent circuit model does not account for space charge effects on power flow. The model was modified to discuss the power transportation through the high power MITLs. With this model, it is possible to estimate the effects of space charge current on the power flow efficiency, without using complicated particle code simulations. (author). 3 figs., 3 refs.

A review on fault classification methodologies in power transmission systems: Part-II

Directory of Open Access Journals (Sweden)

Avagaddi Prasad

2018-05-01

Full Text Available The countless extent of power systems and applications requires the improvement in suitable techniques for the fault classification in power transmission systems, to increase the efficiency of the systems and to avoid major damages. For this purpose, the technical literature proposes a large number of methods. The paper analyzes the technical literature, summarizing the most important methods that can be applied to fault classification methodologies in power transmission systems.The part 2 of the article is named “A review on fault classification methodologies in power transmission systems”. In this part 2 we discussed the advanced technologies developed by various researchers for fault classification in power transmission systems. Keywords: Transmission line protection, Protective relaying, Soft computing techniques

Performance evaluation of power transmission coils for powering endoscopic wireless capsules.

Science.gov (United States)

Basar, Md Rubel; Ahmad, Mohd Yazed; Cho, Jongman; Ibrahim, Fatimah

2015-01-01

This paper presents an analysis of H-field generated by a simple solenoid, pair of solenoids, pair of double-layer solenoids, segmented-solenoid, and Helmholtz power transmission coils (PTCs) to power an endoscopic wireless capsule (WC). The H-fields were computed using finite element analysis based on partial differential equations. Three parameters were considered in the analysis: i) the maximum level of H-field (Hmax) to which the patient's body would be exposed, ii) the minimum level of H-field (Hmin) effective for power transmission, and iii) uniformity of H-field. We validated our analysis by comparing the computed data with data measured from a fabricated Helmholtz PTC. This analysis disclosed that at the same excitation power, all the PTCs are able to transfer same amount of minimum usable power since they generated almost equal value of Hmin. The level of electromagnetic exposure and power transfer stability across all the PTCs would vary significantly which is mainly due to the different level of Hmax and H-field uniformity. The segmented solenoid PTC would cause the lowest exposure and this PTC can transfer the maximum amount of power. The Helmholtz PTC would be able to transfer the most stable power with a moderate level of exposure.

Flexible AC transmission systems modelling and control

CERN Document Server

Zhang, Xiao-Ping; Pal, Bikash

2012-01-01

The extended and revised second edition of this successful monograph presents advanced modeling, analysis and control techniques of Flexible AC Transmission Systems (FACTS). The book covers comprehensively a range of power-system control problems: from steady-state voltage and power flow control, to voltage and reactive power control, to voltage stability control, to small signal stability control using FACTS controllers. In the six years since the first edition of the book has been published research on the FACTS has continued to flourish while renewable energy has developed into a mature and

Efficiency of Finish power transmission network companies

International Nuclear Information System (INIS)

Anon.

2001-01-01

The Finnish Energy Market Authority has investigated the efficiency of power transmissions network companies. The results show that the intensification potential of the branch is 402 million FIM, corresponding to about 15% of the total costs of the branch and 7.3 % of the turnout. Energy Market Authority supervises the reasonableness of the power transmission prices, and it will use the results of the research in supervision. The research was carried out by the Quantitative Methods Research Group of Helsinki School of Economics. The main objective of the research was to create an efficiency estimation method for electric power distribution network business used for Finnish conditions. Data of the year 1998 was used as basic material in the research. Twenty-one of the 102 power distribution network operators was estimated to be totally efficient. Highest possible efficiency rate was 100, and the average of the efficiency rates of all the operators was 76.9, the minimum being 42.6

A Reduced Wind Power Grid Model for Research and Education

DEFF Research Database (Denmark)

Akhmatov, Vladislav; Lund, Torsten; Hansen, Anca Daniela

2007-01-01

A reduced grid model of a transmission system with a number of central power plants, consumption centers, local wind turbines and a large offshore wind farm is developed and implemented in the simulation tool PowerFactory (DIgSILENT). The reduced grid model is given by Energinet.dk, Transmission...

A Suboptimal Power-Saving Transmission Scheme in Multiple Component Carrier Networks

Science.gov (United States)

Chung, Yao-Liang; Tsai, Zsehong

Power consumption due to transmissions in base stations (BSs) has been a major contributor to communication-related CO2 emissions. A power optimization model is developed in this study with respect to radio resource allocation and activation in a multiple Component Carrier (CC) environment. We formulate and solve the power-minimization problem of the BS transceivers for multiple-CC networks with carrier aggregation, while maintaining the overall system and respective users' utilities above minimum levels. The optimized power consumption based on this model can be viewed as a lower bound of that of other algorithms employed in practice. A suboptimal scheme with low computation complexity is proposed. Numerical results show that the power consumption of our scheme is much better than that of the conventional one in which all CCs are always active, if both schemes maintain the same required utilities.

Fuel consumption reduction in urban buses by using power split transmissions

International Nuclear Information System (INIS)

Macor, Alarico; Rossetti, Antonio

2013-01-01

Highlights: • Fuel consumption is highly influenced by transmission layout and control. • Continuous Variable Transmission allows control of the working point of the engine. • Hydromechanical CVT was numerically tested and compared with usual mechanical solutions. • CVT solution proved to reduce fuel consumption, improving the I.C.E. mean efficiency. • Results obtained from standard emission test cycles: New York and Manhattan Buses. - Abstract: The reduction of fuel consumption of urban vehicles is one of the challenges of the society today. Many promising technologies such as hybrid electric vehicles and fuel cells are the focus of a lot of research and investments, but high costs prevent their development on a large scale, especially in heavy duty vehicles. Simpler solutions, such as continuously variable transmissions, are then interesting alternatives: they preserve some of the advantages of hybrid solutions significantly reducing the overall cost of the system. Since these technologies allow the decoupling of the engine’s velocity from that of the wheels, optimised management of the engine becomes feasible, leading to lower fuel consumption than that of traditional solutions. This work compares the hydromechanical transmission with a traditional power shift in an application where efficiency and comfort are required: a city bus. The performance of a vehicle with a dual stage hydromechanical transmission has been investigated by means of a model implemented in the AMESim environment. A second model of a vehicle with a power shift transmission has been taken as reference solution. During the simulation of two standard test cycles, the first vehicle showed the lower fuel consumption, due to its better engine management, and to the operation of the torque converter during starts, which lowers the efficiency of the reference vehicle

Assessment of proactive transmission power control for wireless sensor networks

NARCIS (Netherlands)

kotian, Roshan; Exarchakos, Georgios; Liotta, Antonio

2014-01-01

In order to prolong lifetime of Wireless Sensor Networks (WSN), Transmission Power Control (TPC) techniques are employed. The existing TPC schemes adjust the transmission power mostly reacting to changes at link quality between communicating nodes. Proactive TPC has been proposed in the recent past

High power RF transmission line component development

International Nuclear Information System (INIS)

Hong, B. G.; Hwang, C. K.; Bae, Y. D.; Yoon, J. S.; Wang, S. J.; Gu, S. H.; Yang, J. R.; Hahm, Y. S.; Oh, G. S.; Lee, J. R.; Lee, W. I.; Park, S. H.; Kang, M. S.; Oh, S. H.; Lee, W.I.

1999-12-01

We developed the liquid stub and phase shifter which are the key high RF power transmission line components. They show reliable operation characteristics and increased insulation capability, and reduced the size by using liquid (silicon oil, dielectric constant ε=2.72) instead of gas for insulating dielectric material. They do not have finger stock for the electric contact so the local temperature rise due to irregular contact and RF breakdown due to scratch in conductor are prevented. They can be utilized in broadcasting, radar facility which require high RF power transmission. Moreover, they are key components in RF heating system for fusion reactor. (author)

High power RF transmission line component development

Energy Technology Data Exchange (ETDEWEB)

Hong, B. G.; Hwang, C. K.; Bae, Y. D.; Yoon, J. S.; Wang, S. J.; Gu, S. H.; Yang, J. R.; Hahm, Y. S.; Oh, G. S.; Lee, J. R.; Lee, W. I.; Park, S. H.; Kang, M. S.; Oh, S. H.; Lee, W.I

1999-12-01

We developed the liquid stub and phase shifter which are the key high RF power transmission line components. They show reliable operation characteristics and increased insulation capability, and reduced the size by using liquid (silicon oil, dielectric constant {epsilon}=2.72) instead of gas for insulating dielectric material. They do not have finger stock for the electric contact so the local temperature rise due to irregular contact and RF breakdown due to scratch in conductor are prevented. They can be utilized in broadcasting, radar facility which require high RF power transmission. Moreover, they are key components in RF heating system for fusion reactor. (author)

Mathematical model of transmission network static state estimation

Directory of Open Access Journals (Sweden)

Ivanov Aleksandar

2012-01-01

Full Text Available In this paper the characteristics and capabilities of the power transmission network static state estimator are presented. The solving process of the mathematical model containing the measurement errors and their processing is developed. To evaluate difference between the general model of state estimation and the fast decoupled state estimation model, the both models are applied to an example, and so derived results are compared.

Induction of Inflammation In Vivo by Electrocardiogram Sensor Operation Using Wireless Power Transmission

Directory of Open Access Journals (Sweden)

Jin-Chul Heo

2017-12-01

Full Text Available Prolonged monitoring by cardiac electrocardiogram (ECG sensors is useful for patients with emergency heart conditions. However, implant monitoring systems are limited by lack of tissue biocompatibility. Here, we developed an implantable ECG sensor for real-time monitoring of ventricular fibrillation and evaluated its biocompatibility using an animal model. The implantable sensor comprised transplant sensors with two electrodes, a wireless power transmission system, and a monitoring system. The sensor was inserted into the subcutaneous tissue of the abdominal area and operated for 1 h/day for 5 days using a wireless power system. Importantly, the sensor was encapsulated by subcutaneous tissue and induced angiogenesis, inflammation, and phagocytosis. In addition, we observed that the levels of inflammation-related markers increased with wireless-powered transmission via the ECG sensor; in particular, levels of the Th-1 cytokine interleukin-12 were significantly increased. The results showed that induced tissue damage was associated with the use of wireless-powered sensors. We also investigated research strategies for the prevention of adverse effects caused by lack of tissue biocompatibility of a wireless-powered ECG monitoring system and provided information on the clinical applications of inflammatory reactions in implant treatment using the wireless-powered transmission system.

Wireless Power Transmission Options for Space Solar Power

Science.gov (United States)

Potter, Seth; Davis, Dean; Born, Martin; Bayer, Martin; Howell, Joe; Mankins, John

2008-01-01

Space Solar Power (SSP), combined with Wireless Power Transmission (WPT), offers the far-term potential to solve major energy problems on Earth. In the long term, we aspire to beam energy to Earth from geostationary Earth orbit (GEO), or even further distances in space. In the near term, we can beam power over more moderate distances, but still stretch the limits of today s technology. In recent studies, a 100 kWe-class "Power Plug" Satellite and a 10 kWe-class Lunar Polar Solar Power outpost have been considered as the first steps in using these WPT options for SSP. Our current assessments include consideration of orbits, wavelengths, and structural designs to meet commercial, civilian government, and military needs. Notional transmitter and receiver sizes are considered for use in supplying 5 to 40 MW of power. In the longer term, lunar or asteroidal material can be used. By using SSP and WPT technology for near-term missions, we gain experience needed for sound decisions in designing and developing larger systems to send power from space to Earth.

Technical and economic considerations of extra high voltage power transmission

Energy Technology Data Exchange (ETDEWEB)

Kahnt, R

1966-09-01

The reasons for the employment of higher transmission voltages are listed and the points decisive for the selection of three phase ac or dc systems are reviewed. The technical and economic problems arising in three phase extra high voltage transmission are discussed. These include selection of voltage, economical design of power lines, insulation problems, power supply dependability, equipment rating and reactive power and stability problems.

Wildlife and electric power transmission

Science.gov (United States)

Ellis, D.H.; Goodwin, J.G.; Hunt, J.R.; Fletcher, John L.; Busnel, R.G.

1978-01-01

Hundreds of thousands of miles of transmission lines have been introduced into our natural environment. These lines and their corridors can be damaging or beneficial to wildlife communities depending on how they are designed, where they are placed, and when they are constructed and maintained. With the current trend toward UHV systems, new problems (associated with additional increments in audible noise, electric and magnetic force fields, etc.) must be addressed. We recommend the following areas for careful study: (1) the response of wilderness species to transmission lines and line construction and maintenance activities (2) the magnitude of bird collision and electrocution mortality, (3) the response of power corridor and power tower in habiting wildlife to laboratory and field doses of electro-chemical oxidants, corona noise, electric and magnetic fields, etc., (4) the productivity of tower inhabiting birds compared with nearby non-tower nesters, and (5) the influence of powerline corridors on mammalian and avian migration patterns. It is our hope that the questions identified in this study will help stimulate further research so that we can maximize wildlife benefits and minimize wildlife detriments.

Draft Environmental Impact Statement: BPA/Puget Power Northwest Washington Transmission Project

International Nuclear Information System (INIS)

1993-11-01

Bonneville Power Administration (BPS) and Puget Sound Power ampersand Light (Puget Power) propose to upgrade the existing high-voltage transmission system in the Whatcom and Skagit County area between the towns of Custer and Sedro Woolley, including within the city of Bellingham starting in 1995. The upgrades of the interconnected 230,000 volt (230-kV) and 115-kV systems are needed to increase the reliability of the local transmission system and to increase the import capacity on a nearby US-Canada 500-kV intertie by about 850 megawatts (MW). The increase in north-south transfer capability would be shared by BPA and Puget Power (about 425 MW each). Other actions would include replacement of an existing BPA 230-kV single-circuit, wood-pole H-frame transmission line with a lattice-steel double-circuit line; an existing Puget Power 115-kV single wood-pole transmission line rebuild, two short 115-kV Puget Power lines added at BPA's Bellingham Substation; and improvements made at existing BPA and Puget Power substations

Technical and economic considerations of extra high voltage power transmission

Energy Technology Data Exchange (ETDEWEB)

Kahnt, R

1966-09-01

The reasons for the employment of higher transmission voltages are listed and the points decisive for the selection of three phase ac or dc systems are reviewed. This is followed by treatment of the technical and economic problems arising in three phase-extra high voltage transmission. These include selection of voltage, economical design of power lines, insulation problems, power supply dependability, equipment rating, and reactive power and stability problems.

Simulation Analysis of Transmission-Line Impedance Transformers for Petawatt-Class Pulsed Power Accelerators

International Nuclear Information System (INIS)

Hu Yixiang; Qiu Aici; Sun Fengju; Huang Tao; Cong Peitian; Wang Liangping; Zeng Jiangtao; Li Yan; Zhang Xinjun; Lei Tianshi

2011-01-01

Based on the transmission line code TLCODE, a 1D circuit model for a transmission-line impedance transformer was developed and the simulation results were compared with those in the literature. The model was used to quantify the efficiencies of voltage-transport, energy-transport and power-transport for a transmission-line impedance transformer as functions of ψ (the ratio of the output impedance to the input impedance of the transformer) and Γ (the ratio of the pulse width to the one-way transit time of the transformer) under a large scale of m (the coefficient of the generalized exponential impedance profile). Simulation results suggest that with the increase in Γ, from 0 to ∞, the power transport efficiency first increases and then decreases. The maximum power transport efficiency can reach 90% or even higher for an exponential impedance profile (m = 1). With a consideration of dissipative loss in the dielectric and electrodes of the transformer, two representative designs of the water-insulated transformer are investigated for the next generation of petawatt-class z-pinch drivers. It is found that the dissipative losses in the electrodes are negligibly small, below 0.1%, but the dissipative loss in the water dielectric is about 1% to 4%. (fusion engineering)

Light aircraft sound transmission studies - Noise reduction model

Science.gov (United States)

Atwal, Mahabir S.; Heitman, Karen E.; Crocker, Malcolm J.

1987-01-01

Experimental tests conducted on the fuselage of a single-engine Piper Cherokee light aircraft suggest that the cabin interior noise can be reduced by increasing the transmission loss of the dominant sound transmission paths and/or by increasing the cabin interior sound absorption. The validity of using a simple room equation model to predict the cabin interior sound-pressure level for different fuselage and exterior sound field conditions is also presented. The room equation model is based on the sound power flow balance for the cabin space and utilizes the measured transmitted sound intensity data. The room equation model predictions were considered good enough to be used for preliminary acoustical design studies.

Alleviation SSR and Low Frequency Power Oscillations in Series Compensated Transmission Line using SVC Supplementary Controllers

Science.gov (United States)

Kumar, Sanjiv; Kumar, Narendra

2017-06-01

In this work, supplementary sub-synchronous damping controllers (SSDC) are proposed for damping sub-synchronous oscillations in power systems with series compensated transmission lines. Series compensation have extensively been used as effective means of increasing the power transfer capability of a transmission lines and improving transient stability limits of power systems. Series compensation with transmission lines may cause sub-synchronous resonance (SSR). The eigenvalue investigation tool is used to ascertain the existence of SSR. It is shown that the addition of supplementary controller is able to stabilize all unstable modes for T-network model. Eigenvalue investigation and time domain transient simulation of detailed nonlinear system are considered to investigate the performance of the controllers. The efficacies of the suggested supplementary controllers are compared on the IEEE first benchmark model for computer simulations of SSR by means of time domain simulation in Matlab/Simulink environment. Supplementary SSDC are considered in order to compare effectiveness of SSDC during higher loading in alleviating the small signal stability problem.

A transmission power optimization with a minimum node degree for energy-efficient wireless sensor networks with full-reachability.

Science.gov (United States)

Chen, Yi-Ting; Horng, Mong-Fong; Lo, Chih-Cheng; Chu, Shu-Chuan; Pan, Jeng-Shyang; Liao, Bin-Yih

2013-03-20

Transmission power optimization is the most significant factor in prolonging the lifetime and maintaining the connection quality of wireless sensor networks. Un-optimized transmission power of nodes either interferes with or fails to link neighboring nodes. The optimization of transmission power depends on the expected node degree and node distribution. In this study, an optimization approach to an energy-efficient and full reachability wireless sensor network is proposed. In the proposed approach, an adjustment model of the transmission range with a minimum node degree is proposed that focuses on topology control and optimization of the transmission range according to node degree and node density. The model adjusts the tradeoff between energy efficiency and full reachability to obtain an ideal transmission range. In addition, connectivity and reachability are used as performance indices to evaluate the connection quality of a network. The two indices are compared to demonstrate the practicability of framework through simulation results. Furthermore, the relationship between the indices under the conditions of various node degrees is analyzed to generalize the characteristics of node densities. The research results on the reliability and feasibility of the proposed approach will benefit the future real deployments.

A Transmission Power Optimization with a Minimum Node Degree for Energy-Efficient Wireless Sensor Networks with Full-Reachability

Science.gov (United States)

Chen, Yi-Ting; Horng, Mong-Fong; Lo, Chih-Cheng; Chu, Shu-Chuan; Pan, Jeng-Shyang; Liao, Bin-Yih

2013-01-01

Transmission power optimization is the most significant factor in prolonging the lifetime and maintaining the connection quality of wireless sensor networks. Un-optimized transmission power of nodes either interferes with or fails to link neighboring nodes. The optimization of transmission power depends on the expected node degree and node distribution. In this study, an optimization approach to an energy-efficient and full reachability wireless sensor network is proposed. In the proposed approach, an adjustment model of the transmission range with a minimum node degree is proposed that focuses on topology control and optimization of the transmission range according to node degree and node density. The model adjusts the tradeoff between energy efficiency and full reachability to obtain an ideal transmission range. In addition, connectivity and reachability are used as performance indices to evaluate the connection quality of a network. The two indices are compared to demonstrate the practicability of framework through simulation results. Furthermore, the relationship between the indices under the conditions of various node degrees is analyzed to generalize the characteristics of node densities. The research results on the reliability and feasibility of the proposed approach will benefit the future real deployments. PMID:23519351

The future of power transmission and distribution in India

International Nuclear Information System (INIS)

Parakh, S.C.

1995-01-01

India's growing economy requires considerable investment in the power sector. Though rapid strides have been made, the power sector has been unable to supply quality power and demand is continuously outstripping supply. The future of power transmission and distribution in India is discussed. 2 tabs

A novel power efficient location-based cooperative routing with transmission power-upper-limit for wireless sensor networks.

Science.gov (United States)

Shi, Juanfei; Calveras, Anna; Cheng, Ye; Liu, Kai

2013-05-15

The extensive usage of wireless sensor networks (WSNs) has led to the development of many power- and energy-efficient routing protocols. Cooperative routing in WSNs can improve performance in these types of networks. In this paper we discuss the existing proposals and we propose a routing algorithm for wireless sensor networks called Power Efficient Location-based Cooperative Routing with Transmission Power-upper-limit (PELCR-TP). The algorithm is based on the principle of minimum link power and aims to take advantage of nodes cooperation to make the link work well in WSNs with a low transmission power. In the proposed scheme, with a determined transmission power upper limit, nodes find the most appropriate next nodes and single-relay nodes with the proposed algorithm. Moreover, this proposal subtly avoids non-working nodes, because we add a Bad nodes Avoidance Strategy (BAS). Simulation results show that the proposed algorithm with BAS can significantly improve the performance in reducing the overall link power, enhancing the transmission success rate and decreasing the retransmission rate.

A Novel Power Efficient Location-Based Cooperative Routing with Transmission Power-Upper-Limit for Wireless Sensor Networks

Science.gov (United States)

Shi, Juanfei; Calveras, Anna; Cheng, Ye; Liu, Kai

2013-01-01

The extensive usage of wireless sensor networks (WSNs) has led to the development of many power- and energy-efficient routing protocols. Cooperative routing in WSNs can improve performance in these types of networks. In this paper we discuss the existing proposals and we propose a routing algorithm for wireless sensor networks called Power Efficient Location-based Cooperative Routing with Transmission Power-upper-limit (PELCR-TP). The algorithm is based on the principle of minimum link power and aims to take advantage of nodes cooperation to make the link work well in WSNs with a low transmission power. In the proposed scheme, with a determined transmission power upper limit, nodes find the most appropriate next nodes and single-relay nodes with the proposed algorithm. Moreover, this proposal subtly avoids non-working nodes, because we add a Bad nodes Avoidance Strategy (BAS). Simulation results show that the proposed algorithm with BAS can significantly improve the performance in reducing the overall link power, enhancing the transmission success rate and decreasing the retransmission rate. PMID:23676625

Experiment of Power Supply Method for WLAN Sensor Using Both Energy Harvesting and Microwave Power Transmission

International Nuclear Information System (INIS)

Sakaguchi, K; Yamashita, S; Yamamoto, K; Nishio, T; Morikura, M; Huang, Y; Shinohara, N

2014-01-01

This paper proposes to improve effectiveness of supplying a sensor with energy using microwave power transmission (MPT) and energy harvesting (EH). The MPT duration should be as short as possible to avoid serious interference between the MPT and wireless local area network data transmission when co-channel operation of both microwave power transmission (MPT) and wireless data transmissions is performed. To shorten the MPT duration, we use multiple power sources such as an MPT source and an EH source to supply a sensor with power. Here, an overcharge or an energy shortage could occur at the sensor if the power supplied by both the MPT and EH sources is not adjusted appropriately. To solve this problem, the power supplied by multiple sources should be estimated precisely. In this paper, we propose a scheme for estimating the power supplied by multiple sources on the basis of an existing MPT scheduling system and then conducted an experiment using the scheme. From the experimental results, it is confirmed to estimate the power supplied by multiple sources successfully. In addition, the required MPT duration when the EH source is used is reduced compared to that when it is not used. Moreover, it is confirmed that the sensor station successfully estimates the power supplied by an MPT source and that by an EH source and adequately configures the MPT duration

Harmonics in Offshore Wind Power Plants Employing Power Electronic Devices in the Transmission System

DEFF Research Database (Denmark)

Glasdam, Jakob Bærholm

Introduction The trend in power generation is to partly replace conventional power plants with renewable energy sources. Offshore wind power has been selected to take up a significant proportion of the renewable energy production. The grid codes have been updated to accommodate the rising share...... of wind power. The onshore as well as offshore wind power plants (OWPPs) therefore have to meet the same stringent requirement as the conventional power plants. This can be accommodated by employment of flexible alternating current transmission system (FACTS) devices, such as the static compensator...... gives rise to a number of challenges to the wind power industry with regard to construction, installation as well as transmission of the generated energy. The STATCOM and the voltage-sourced converter high-voltage direct current (VSC-HVDC) are attractive solutions for grid connection of remotely located...

Wireless Power Transmission via Sheet Medium Using Automatic Phase Adjustment of Multiple Inputs

Science.gov (United States)

Matsuda, Takashi; Oota, Toshifumi; Kado, Youiti; Zhang, Bing

The wireless power transmission via sheet medium is a novel physical form of communication that utilizes the surface as a medium to provide both data and power transmission services. To efficiently transmit a relatively-large amount of electric power (several watts), we have developed a wireless power transmission system via sheet medium that concentrates the electric power on a specific spot by using phase control of multiple inputs. However, to find the optimal phases of the multiple inputs making the microwave converge on a specific spot in the sheet medium, the prior knowledge of the device's position, and the pre-experiment measuring the output power, are needed. In wireless communication area, it is known that the retrodirective array scheme can efficiently transmit the power in a self-phasing manner, which uses the pilot signals sent by the client devices. In this paper, we apply the retrodirective array scheme to the wireless power transmission system via sheet medium, and propose a power transmission scheme using the phase-adjustment of multiple inputs. To confirm the effectiveness of the proposal scheme, we evaluate its performance by computer simulation and realistic measurement. Both results show that the proposal scheme can achieve the retrodirectivity over the wireless power transmission via sheet medium.

High-Power Microwave Transmission and Mode Conversion Program

Energy Technology Data Exchange (ETDEWEB)

Vernon, Ronald J. [Univ. of Wisconsin, Madison, WI (United States)

2015-08-14

This is a final technical report for a long term project to develop improved designs and design tools for the microwave hardware and components associated with the DOE Plasma Fusion Program. We have developed basic theory, software, fabrication techniques, and low-power measurement techniques for the design of microwave hardware associated gyrotrons, microwave mode converters and high-power microwave transmission lines. Specifically, in this report we discuss our work on designing quasi-optical mode converters for single and multiple frequencies, a new method for the analysis of perturbed-wall waveguide mode converters, perturbed-wall launcher design for TE0n mode gyrotrons, quasi-optical traveling-wave resonator design for high-power testing of microwave components, and possible improvements to the HSX microwave transmission line.

Study on Tower Models for EHV Transmission Line

Directory of Open Access Journals (Sweden)

Xu Bao-Qing

2016-01-01

Full Text Available Lightning outage accident is one of the main factors that threat seriously the safe and reliable operation of power system. So it is very important to establish reasonable transmission tower model and evaluate the impulse response characteristic of lightning wave traveling on the transmission tower properly for determining reliable lightning protection performance. With the help of Electromagnetic Transient Program (EMTP, six 500kV tower models are built. Aiming at one line to one transformer operating mode of 500kV substation, the intruding wave overvoltage under different tower models is calculated. The effect of tower model on intruding overvoltage has been studied. The results show that different tower models can result in great differences to the calculation results. Hence, reasonable selection of the tower model in the calculation of back- strike intruding wave is very important.

An asymmetric resonant coupling wireless power transmission link for Micro-Ball Endoscopy.

Science.gov (United States)

Sun, Tianjia; Xie, Xiang; Li, Guolin; Gu, Yingke; Deng, Yangdong; Wang, Ziqiang; Wang, Zhihua

2010-01-01

This paper investigates the design and optimization of a wireless power transmission link targeting Micro-Ball Endoscopy applications. A novel asymmetric resonant coupling structure is proposed to deliver power to an endoscopic Micro-Ball system for image read-out after it is excreted. Such a technology enables many key medical applications with stringent requirements for small system volume and high power delivery efficiency. A prototyping power transmission sub-system of the Micro-Ball system was implemented. It consists of primary coil, middle resonant coil, and cube-like full-direction secondary receiving coils. Our experimental results proved that 200mW of power can be successfully delivered. Such a wireless power transmission capability could satisfy the requirements of the Micro-Ball based endoscopy application. The transmission efficiency is in the range of 41% (worst working condition) to 53% (best working condition). Comparing to conventional structures, Asymmetric Resonant Coupling Structure improves power efficiency by 13%.

Transmission Integration | Grid Modernization | NREL

Science.gov (United States)

Transmission Integration Transmission Integration The goal of NREL's transmission integration integration issues and provide data, analysis, and models to enable the electric power system to more and finding solutions to address them to enable transmission grid integration. Capabilities Power

Interference Cancellation for Coexisting Wireless Data and Power Transmission in the Same Frequency

International Nuclear Information System (INIS)

Yamazaki, Keita; Sugiyama, Yusuke; Saruwatari, Shunsuke; Kawahara, Yoshihiro; Watanabe, Takashi

2014-01-01

Combining wireless transmission of data and power signals enables wireless sensor networks to drive perpetually without changing batteries. To achieve the simultaneous data and power transmission, the present paper proposes power signal interference cancellation for wireless data and power transmission at the same time in the same frequency. We evaluate the performance of the proposed power signal interference cancellation using Universal Software Radio Peripheral N200 (USRP N200) software defined radio. Evaluations show that the proposed interference cancellation is feasible to receive data while transmitting power

Energy losses of superconducting power transmission cables in the grid

DEFF Research Database (Denmark)

Østergaard, Jacob; Okholm, Jan; Lomholt, Karin

2001-01-01

One of the obvious motives for development of superconducting power transmission cables is reduction of transmission losses. Loss components in superconducting cables as well as in conventional cables have been examined. These losses are used for calculating the total energy losses of conventional...... as well as superconducting cables when they are placed in the electric power transmission network. It is concluded that high load connections are necessary to obtain energy saving by the use of HTSC cables. For selected high load connections, an energy saving of 40% is expected. It is shown...

Study on electromagnetic characteristics of the magnetic coupling resonant coil for the wireless power transmission system.

Science.gov (United States)

Wang, Zhongxian; Liu, Yiping; Wei, Yonggeng; Song, Yilin

2018-01-01

The resonant coil design is taken as the core technology in the magnetic coupling resonant wireless power transmission system, which achieves energy transmission by the coupling of the resonant coil. This paper studies the effect of the resonant coil on energy transmission and the efficiency of the system. Combining a two-coil with a three-coil system, the optimum design method for the resonant coil is given to propose a novel coil structure. First, the co-simulation methods of Pspice and Maxwell are used. When the coupling coefficient of the resonant coil is different, the relationship between system transmission efficiency, output power, and frequency is analyzed. When the self-inductance of the resonant coil is different, the relationship between the performance and frequency of the system transmission is analyzed. Then, two-coil and three-coil structure models are built, and the parameters of the magnetic field of the coils are calculated and analyzed using the finite element method. In the end, a dual E-type simulation circuit model is used to optimize the design of the novel resonance coil. The co-simulation results show that the coupling coefficients of the two-coil, three-coil, and novel coil systems are 0.017, 0.17 and 0.0126, respectively. The power loss of the novel coil is 16.4 mW. There is an obvious improvement in the three-coil system, which shows that the magnetic leakage of the field and the energy coupling are relatively small. The new structure coil has better performance, and the load loss is lower; it can improve the system output power and transmission efficiency.

HVDC Transmission an Outlook and Significance for Pakistani Power Sector

Science.gov (United States)

Ahmad, Muhammad; Wang, Zhixin; Wang, Jinjian; Baloach, Mazhar H.; Longxin, Bao; Hua, Qing

2018-04-01

Recently a paradigm shift in the power sector is observed, i.e., countries across the globe have deviated their attention to distributed generation rather than conventional centralized bulk generation. Owing to the above narrative, distributed energy resources e.g., wind and PV have gained the adequate attention of governments and researchers courtesy to their eco-friendly nature. On the contrary, the increased infiltration of distributed generation to the power system has introduced many technical and economical glitches such as long-distance transmission, transmission lines efficiency, control capability and cost etc. To mitigate these complications, the utility of high voltage direct current (HVDC) transmission has emerged as a possible solution. In this context, this paper includes a brief discussion on the fundamentals HVDC and its significance in Pakistani power sector. Furthermore, the potential of distributed energy resources for Pakistan is also the subject matter of this paper, so that significance of HVDC transmission can effectively be deliberated.

Development and Application of Wireless Power Transmission Systems for Wireless ECG Sensors

Directory of Open Access Journals (Sweden)

Jin-Chul Heo

2018-01-01

Full Text Available We investigated the variations in the magnetic field distribution and power transmission efficiency, resulting from changes in the relative positions of the transmitting and receiving coils, for electromagnetic induction-type wireless power transmission using an elliptical receive coil. Results of simulations using a high-frequency structure simulator were compared to actual measurement results. The simulations showed that the transmission efficiency could be maintained relatively stable even if the alignment between the transmitting and receiving coils was changed to some extent. When the centre of the receiving coil was perfectly aligned with the centre of the transmitting coil, the transmission efficiency was in the maximum; however, the degree of decrease in the transmission efficiency was small even if the centre of the receiving coil moved by ±10 mm from the centre of the transmitting coil. Therefore, it is expected that the performance of the wireless power transmission system will not be degraded significantly even if perfect alignment is not maintained. Animal experiments confirmed good ECG signals for the simulation conditions. The results suggested a standardized application method of wireless transmission in the utilization of wireless power for implantable sensors.

Effects of Scandinavian hydro power on storage needs in a fully renewable European power system for various transmission capacity scenarios

Science.gov (United States)

Kies, Alexander; Nag, Kabitri; von Bremen, Lueder; Lorenz, Elke; Heinemann, Detlev

2015-04-01

The penetration of renewable energies in the European power system has increased in the last decades (23.5% share of renewables in the gross electricity consumption of the EU-28 in 2012) and is expected to increase further up to very high shares close to 100%. Planning and organizing this European energy transition towards sustainable power sources will be one of the major challenges of the 21st century. It is very likely that in a fully renewable European power system wind and photovoltaics (pv) will contribute the largest shares to the generation mix followed by hydro power. However, feed-in from wind and pv is due to the weather dependant nature of their resources fluctuating and non-controllable. To match generation and consumption several solutions and their combinations were proposed like very high backup-capacities of conventional power generation (e.g. fossile or nuclear), storages or the extension of the transmission grid. Apart from those options hydro power can be used to counterbalance fluctuating wind and pv generation to some extent. In this work we investigate the effects of hydro power from Norway and Sweden on residual storage needs in Europe depending on the overlaying grid scenario. High temporally and spatially resolved weather data with a spatial resolution of 7 x 7 km and a temporal resolution of 1 hour was used to model the feed-in from wind and pv for 34 investigated European countries for the years 2003-2012. Inflow into hydro storages and generation by run-of-river power plants were computed from ERA-Interim reanalysis runoff data at a spatial resolution of 0.75° x 0.75° and a daily temporal resolution. Power flows in a simplified transmission grid connecting the 34 European countries were modelled minimizing dissipation using a DC-flow approximation. Previous work has shown that hydro power, namely in Norway and Sweden, can reduce storage needs in a renewable European power system by a large extent. A 15% share of hydro power in Europe

Interregional power transmission: a component in planning for renewable energy technologies

International Nuclear Information System (INIS)

Krueger Nielsen, S.; Soerensen, B.

2000-01-01

We discuss the role played by interregional power transmission on the basis of recent scenario work. In a project dealing with long-term planning for energy efficiency and renewable energy in Europe we modelled a scenario for the present 15 EU countries' energy system in 2050. The basis for the scenario is the concept of 'fair pricing' for energy services, meaning that the price of energy should reflect all externalities, but not otherwise be taxed or subsidized. The project assessed resource availability and expected technology price developments over time for a number of energy-related technologies, both on the supply side, the intermediate conversion chain and on the demand side. Among these, transmission technologies play an important role, both in smoothing out renewable energy supplies within the European Union region, and also allowing substantial import of energy from countries outside the EU having a surplus of renewable energy based power. (orig.)

Enhanced Wireless Power Transmission Using Strong Paramagnetic Response.

Science.gov (United States)

Ahn, Dukju; Kiani, Mehdi; Ghovanloo, Maysam

2014-03-01

A method of quasi-static magnetic resonant coupling has been presented for improving the power transmission efficiency (PTE) in near-field wireless power transmission, which improves upon the state of the art. The traditional source resonator on the transmitter side is equipped with an additional resonator with a resonance frequency that is tuned substantially higher than the magnetic field excitation frequency. This additional resonator enhances the magnetic dipole moment and the effective permeability of the power transmitter, owing to a phenomenon known as the strong paramagnetic response. Both theoretical calculations and experimental results show increased PTE due to amplification of the effective permeability. In measurements, the PTE was improved from 57.8% to 64.2% at the nominal distance of 15 cm when the effective permeability was 2.6. The power delivered to load was also improved significantly, with the same 10 V excitation voltage, from 0.38 to 5.26 W.

Nonsynchronous vibrations observed in a supercritical power transmission shaft

Science.gov (United States)

Darlow, M. S.; Zorzi, E. S.

1979-01-01

A flexible shaft is prone to a number of vibration phenomena which occur at frequencies other than synchronous with rotational speed. Nonsynchronous vibrations from several sources were observed while running a test rig designed to simulate the operation of a supercritical power transmission shaft. The test rig was run first with very light external damping and then with a higher level of external damping, for comparison. As a result, the effect of external damping on the nonsynchronous vibrations of the test rig was observed. All of these nonsynchronous vibrations were of significant amplitude. Their presence in the vibrations spectra for a supercritical power transmission shaft at various speeds in the operating range indicates that very careful attention to all of the vibration spectra should be made in any supercritical power transmission shafting. This paper presents a review of the analysis performed and a comparison with experimental data. A thorough discussion of the observed nonsynchronous whirl is also provided.

Research on Capacity Addition using Market Model with Transmission Congestion under Competitive Environment

Science.gov (United States)

Katsura, Yasufumi; Attaviriyanupap, Pathom; Kataoka, Yoshihiko

In this research, the fundamental premises for deregulation of the electric power industry are reevaluated. The authors develop a simple model to represent wholesale electricity market with highly congested network. The model is developed by simplifying the power system and market in New York ISO based on available data of New York ISO in 2004 with some estimation. Based on the developed model and construction cost data from the past, the economic impact of transmission line addition on market participants and the impact of deregulation on power plant additions under market with transmission congestion are studied. Simulation results show that the market signals may fail to facilitate proper capacity additions and results in the undesirable over-construction and insufficient-construction cycle of capacity addition.

Market power in the European electricity market - The impacts of dry weather and additional transmission capacity

International Nuclear Information System (INIS)

Lise, Wietze; Hobbs, Benjamin F.; Hers, Sebastiaan

2008-01-01

This paper uses a static computational game theoretic model of a fully opened European electricity market and can take strategic interaction among electricity-producing firms into account. The model is run for a number of scenarios: first, in the baseline under perfect competition, the prices differ due to the presence of various generation technologies and a limited ability to exchange electricity among countries. In addition, when large firms exercise market power, the model runs indicate that prices are the highest in countries where the number of firms is low. Second, dry weather would increase the prices in the hydro-rich Nordic countries followed by the Alpine countries. The price response would be about 20% higher with market power. Third, more transmission capacity would lower the prices in countries with high prices and it also reduces the impact of market power. Hence, more transmission capacity can improve market competitiveness. (author)

Market power in the European electricity market-The impacts of dry weather and additional transmission capacity

Energy Technology Data Exchange (ETDEWEB)

Lise, Wietze [IBS Research and Consultancy, Agahamami Cadessi 1/6, Aga Han, Cihangir, 34433 Beyoglu, Istanbul (Turkey); Energy Markets and International Environmental Policy Group, ECN Policy Studies, Energy Research Centre of the Netherlands, Amsterdam (Netherlands)], E-mail: wietze.lise@ibsresearch.com; Hobbs, Benjamin F. [Department of Geography and Environmental Engineering, Johns Hopkins University, Baltimore, MD 21218 (United States); Hers, Sebastiaan [Energy Markets and International Environmental Policy Group, ECN Policy Studies, Energy Research Centre of the Netherlands, Amsterdam (Netherlands)

2008-04-15

This paper uses a static computational game theoretic model of a fully opened European electricity market and can take strategic interaction among electricity-producing firms into account. The model is run for a number of scenarios: first, in the baseline under perfect competition, the prices differ due to the presence of various generation technologies and a limited ability to exchange electricity among countries. In addition, when large firms exercise market power, the model runs indicate that prices are the highest in countries where the number of firms is low. Second, dry weather would increase the prices in the hydro-rich Nordic countries followed by the Alpine countries. The price response would be about 20% higher with market power. Third, more transmission capacity would lower the prices in countries with high prices and it also reduces the impact of market power. Hence, more transmission capacity can improve market competitiveness.

Market power in the European electricity market - The impacts of dry weather and additional transmission capacity

Energy Technology Data Exchange (ETDEWEB)

Lise, Wietze [IBS Research and Consultancy, Agahamami Cadessi 1/6, Aga Han, Cihangir, 34433 Beyoglu, Istanbul (Turkey); Energy Markets and International Environmental Policy Group, ECN Policy Studies, Energy Research Centre of the Netherlands, Amsterdam (Netherlands); Hobbs, Benjamin F. [Department of Geography and Environmental Engineering, Johns Hopkins University, Baltimore, MD 21218 (United States); Hers, Sebastiaan [Energy Markets and International Environmental Policy Group, ECN Policy Studies, Energy Research Centre of the Netherlands, Amsterdam (Netherlands)

2008-04-15

This paper uses a static computational game theoretic model of a fully opened European electricity market and can take strategic interaction among electricity-producing firms into account. The model is run for a number of scenarios: first, in the baseline under perfect competition, the prices differ due to the presence of various generation technologies and a limited ability to exchange electricity among countries. In addition, when large firms exercise market power, the model runs indicate that prices are the highest in countries where the number of firms is low. Second, dry weather would increase the prices in the hydro-rich Nordic countries followed by the Alpine countries. The price response would be about 20% higher with market power. Third, more transmission capacity would lower the prices in countries with high prices and it also reduces the impact of market power. Hence, more transmission capacity can improve market competitiveness. (author)

Power consumption analysis of constant bit rate video transmission over 3G networks

DEFF Research Database (Denmark)

Ukhanova, Ann; Belyaev, Evgeny; Wang, Le

2012-01-01

This paper presents an analysis of the power consumption of video data transmission with constant bit rate over 3G mobile wireless networks. The work includes the description of the radio resource control transition state machine in 3G networks, followed by a detailed power consumption analysis...... and measurements of the radio link power consumption. Based on this description and analysis, we propose our power consumption model. The power model was evaluated on a smartphone Nokia N900, which follows 3GPP Release 5 and 6 supporting HSDPA/HSUPA data bearers. We also propose a method for parameter selection...... for the 3GPP transition state machine that allows to decrease power consumption on a mobile device taking signaling traffic, buffer size and latency restrictions into account. Furthermore, we discuss the gain in power consumption vs. PSNR for transmitted video and show the possibility of performing power...

Efficient utilization of wind power: Long-distance transmission or local consumption?

Science.gov (United States)

Sun, Yuanzhang; Ma, Xiyuan; Xu, Jian; Bao, Yi; Liao, Siyang

2017-09-01

Excess wind power produced in wind-intensive areas is normally delivered to remote load centers via long-distance transmission lines. This paper presents a comparison between long-distance transmission, which has gained popularity, and local energy consumption, in which a fraction of the generated wind power can be locally consumed by energy-intensive industries. First, the challenges and solutions to the long-distance transmission and local consumption of wind power are presented. Then, the two approaches to the utilization of wind power are compared in terms of system security, reliability, cost, and capability to utilize wind energy. Finally, the economic feasibility and technical feasibility of the local consumption of wind power are demonstrated by a large and isolated industrial power system, or supermicrogrid, in China. The coal-fired generators together with the short-term interruptible electrolytic aluminum load in the supermicrogrid are able to compensate for the intermittency of wind power. In the long term, the transfer of high-energy-consumption industries to wind-rich areas and their local consumption of the available wind power are beneficial.

Efficient utilization of wind power: Long-distance transmission or local consumption?

Institute of Scientific and Technical Information of China (English)

Yuanzhang SUN; Xiyuan MA; Jian XU; Yi BAO; Siyang LIAO

2017-01-01

Excess wind power produced in wind-intensive areas is normally delivered to remote load centers via long-distance transmission lines.This paper presents a comparison between long-distance transmission,which has gained popularity,and local energy consumption,in which a fraction of the generated wind power can be locally consumed by energy-intensive industries.First,the challenges and solutions to the long-distance transmission and local consumption of wind power are presented.Then,the two approaches to the utilization of wind power are compared in terms of system security,reliability,cost,and capability to utilize wind energy.Finally,the economic feasibility and technical feasibility of the local consumption of wind power are demonstrated by a large and isolated industrial power system,or supermicrogrid,in China.The coal-fired generators together with the shortterm interruptible electrolytic aluminum load in the supermicrogrid are able to compensate for the intermittency of wind power.In the long term,the transfer of highenergy-consumption industries to wind-rich areas and their local consumption of the available wind power are beneficial.

Characteristic of wireless power transmission S-Parameter for a superconductor coil

International Nuclear Information System (INIS)

Jeong, In Sung; Jung, Byung Ik; Choi, Hyo Sang

2015-01-01

Many studies are being conducted to implement wireless charging, for example, for cellular phones or electronic tooth brushes, via wireless power transmission technique. However, the magnetic induction method had a very short transmission distance. To solve this problem, the team of Professor Marin Soljacic proposed a magnetic resonance system that used two resonance coils with the same resonance frequency. It had an approximately 40% efficiency at a 2m distance. The system improved the low efficiency and short distance problems of the existing systems. So it could also widen the application range of wireless power transmission. Many studies on the subject are underway. In this paper, the superconductor coil was used to improve the efficiency of magnetic resonance wireless power transmission. The resonance wireless power transmission system had a source coil, a load coil, and resonance coils (a transmitter and a receiver). The efficiency and distance depended on the characteristics of the transmitter and receiver coils that had the same resonance frequency. Therefore, two resonance coils were fabricated by superconductors. The current density of the superconductor was higher than that of the normal conductor coil. Accordingly, it had a high quality-factor and improved efficiency

Characteristic of wireless power transmission S-Parameter for a superconductor coil

Energy Technology Data Exchange (ETDEWEB)

Jeong, In Sung; Jung, Byung Ik; Choi, Hyo Sang [Chosun University, Gwangju (Korea, Republic of)

2015-03-15

Many studies are being conducted to implement wireless charging, for example, for cellular phones or electronic tooth brushes, via wireless power transmission technique. However, the magnetic induction method had a very short transmission distance. To solve this problem, the team of Professor Marin Soljacic proposed a magnetic resonance system that used two resonance coils with the same resonance frequency. It had an approximately 40% efficiency at a 2m distance. The system improved the low efficiency and short distance problems of the existing systems. So it could also widen the application range of wireless power transmission. Many studies on the subject are underway. In this paper, the superconductor coil was used to improve the efficiency of magnetic resonance wireless power transmission. The resonance wireless power transmission system had a source coil, a load coil, and resonance coils (a transmitter and a receiver). The efficiency and distance depended on the characteristics of the transmitter and receiver coils that had the same resonance frequency. Therefore, two resonance coils were fabricated by superconductors. The current density of the superconductor was higher than that of the normal conductor coil. Accordingly, it had a high quality-factor and improved efficiency.

A Novel Power-Saving Transmission Scheme for Multiple-Component-Carrier Cellular Systems

Directory of Open Access Journals (Sweden)

Yao-Liang Chung

2016-04-01

Full Text Available As mobile data traffic levels have increased exponentially, resulting in rising energy costs in recent years, the demand for and development of green communication technologies has resulted in various energy-saving designs for cellular systems. At the same time, recent technological advances have allowed multiple component carriers (CCs to be simultaneously utilized in a base station (BS, a development that has made the energy consumption of BSs a matter of increasing concern. To help address this concern, herein we propose a novel scheme aimed at efficiently minimizing the power consumption of BS transceivers during transmission, while still ensuring good service quality and fairness for users. Specifically, the scheme utilizes the dynamic activation/deactivation of CCs during data transmission to increase power usage efficiency. To test its effectiveness, the proposed scheme was applied to a model consisting of a BS with orthogonal frequency division multiple access-based CCs in a downlink transmission environment. The results indicated that, given periods of relatively light traffic loads, the total power consumption of the proposed scheme is significantly lower than that of schemes in which all the CCs of a BS are constantly activated, suggesting the scheme’s potential for reducing both energy costs and carbon dioxide emissions.

Development of a coordinated control system for BWR nuclear power plant and HVDC transmission system

International Nuclear Information System (INIS)

Ishikawa, M.; Hara, T.; Hirayama, K.; Sekiya, K.

1986-01-01

The combined use of dc and ac transmissions or so-called hybrid transmission was under study, employing both dc and ac systems to enable stable transmission of 10,000 MW of electric power generated by the BWR nuclear plant, scheduled to be built about 800 km away from the center of the load. It was thus necessary to develop a hybrid power transmission control system, the hybrid power transmission system consisting of a high voltage dc transmission system (HVDC) and an ultrahigh ac transmission system (UHVAC). It was also necessary to develop a control system for HVDC transmission which protects the BWR nuclear power plant from being influenced by any change in transmission mode that occurs as a result of faults on the UHVAC side when the entire power of the BWR plant is being sent by the HVDC transmission. This paper clarifies the requirements for the HVDC system control during hybrid transmission and also during dc transmission. The control method that satisfies these requirements was studied to develop a control algorithm

Second Order Cone Programming (SOCP) Relaxation Based Optimal Power Flow with Hybrid VSC-HVDC Transmission and Active Distribution Networks

DEFF Research Database (Denmark)

Ding, Tao; Li, Cheng; Yang, Yongheng

2017-01-01

The detailed topology of renewable resource bases may have the impact on the optimal power flow of the VSC-HVDC transmission network. To address this issue, this paper develops an optimal power flow with the hybrid VSC-HVDC transmission and active distribution networks to optimally schedule...... the generation output and voltage regulation of both networks, which leads to a non-convex programming model. Furthermore, the non-convex power flow equations are based on the Second Order Cone Programming (SOCP) relaxation approach. Thus, the proposed model can be relaxed to a SOCP that can be tractably solved...

Electrical Structure of Future Off-shore Wind Power Plant with a High Voltage Direct Current Power Transmission

DEFF Research Database (Denmark)

Sharma, Ranjan

The increasing demand of electric power and the growing consciousness towards the changing climate has led to a rapid development of renewable energy in the recent years. Among all, wind energy has been the fastest growing energy source in the last decade. But the growing size of wind power plants......, better wind conditions at off-shore and the general demand to put them out of sight have all contributed to the installation of large wind power plants in off-shore condition. However, moving wind power plants far out in the off-shore comes with many associated problems. One of the main challenges...... is the transmission of power over long distance. Historically, the power transmission from off-shore wind power plants has been done via HVAC submarine cables. This provides a simple solution, but AC cables cannot be arbitrarily long. It is shown in the report that major issues with HVAC cable transmission system...

Research on hybrid transmission mode for HVDC with optimal thermal power and renewable energy combination

Science.gov (United States)

Zhang, Jinfang; Yan, Xiaoqing; Wang, Hongfu

2018-02-01

With the rapid development of renewable energy in Northwest China, curtailment phenomena is becoming more and more serve owing to lack of adjustment ability and enough transmission capacity. Based on the existing HVDC projects, exploring the hybrid transmission mode associated with thermal power and renewable power will be necessary and important. This paper has proposed a method on optimal thermal power and renewable energy combination for HVDC lines, based on multi-scheme comparison. Having established the mathematic model for electric power balance in time series mode, ten different schemes have been picked for figuring out the suitable one by test simulation. By the proposed related discriminated principle, including generation device utilization hours, renewable energy electricity proportion and curtailment level, the recommendation scheme has been found. The result has also validated the efficiency of the method.

Power transmission pricing: issues and international experience

International Nuclear Information System (INIS)

Bodenhoefer, H.J.; Wohlgemuth, N.

2001-01-01

A key aspect of electricity industry reorganization is transmission pricing because it heavily influences the degree of effective competition in 'liberalized' electricity markets. this paper presents an overview transmission pricing models, of issues related to an effective design of a transmission pricing approach, and presents approaches implemented internationally. A conclusion is that, due to the great number of institutional designs of electricity market organizations, particularly in Europe, it will be difficult to design/implement a model of cross-border transmission pricing that is capable of inducing a high degree of non-discriminatory international competition in electricity markets. (author)

Analysis of Power Network for Line Reactance Variation to Improve Total Transmission Capacity

Directory of Open Access Journals (Sweden)

Ikram Ullah

2016-11-01

Full Text Available The increasing growth in power demand and the penetration of renewable distributed generations in competitive electricity market demands large and flexible capacity from the transmission grid to reduce transmission bottlenecks. The bottlenecks cause transmission congestion, reliability problems, restrict competition, and limit the maximum dispatch of low cost generations in the network. The electricity system requires efficient utilization of the current transmission capability to improve the Available Transfer Capability (ATC. To improve the ATC, power flow among the lines can be managed by using Flexible AC Transmission System (FACTS devices as power flow controllers, which alter the parameters of power lines. It is important to place FACTS devices on suitable lines to vary the reactance for improving Total Transmission Capacity (TTC of the network and provide flexibility in the power flow. In this paper a transmission network is analyzed based on line parameters variation to improve TTC of the interconnected system. Lines are selected for placing FACTS devices based on real power flow Performance Index (PI sensitivity factors. TTC is computed using the Repeated Power Flow (RPF method using the constraints of lines thermal limits, bus voltage limits and generator limits. The reactance of suitable lines, selected on the basis of PI sensitivity factors are changed to divert the power flow to other lines with enough transfer capacity available. The improvement of TTC using line reactance variation is demonstrated with three IEEE test systems with multi-area networks. The results show the variation of the selected lines’ reactance in improving TTC for all the test networks with defined contingency cases.

Literature Survey on Operational Voltage Control and Reactive Power Management on Transmission and Sub-Transmission Networks

Energy Technology Data Exchange (ETDEWEB)

Elizondo, Marcelo A.; Samaan, Nader A.; Makarov, Yuri V.; Holzer, Jesse T.; Vallem, Mallikarjuna R.; Huang, Renke; Vyakaranam, Bharat GNVSR; Ke, Xinda; Pan, Feng

2017-10-02

Voltage and reactive power system control is generally performed following usual patterns of loads, based on off-line studies for daily and seasonal operations. This practice is currently challenged by the inclusion of distributed renewable generation, such as solar. There has been focus on resolving this problem at the distribution level; however, the transmission and sub-transmission levels have received less attention. This paper provides a literature review of proposed methods and solution approaches to coordinate and optimize voltage control and reactive power management, with an emphasis on applications at transmission and sub-transmission level. The conclusion drawn from the survey is that additional research is needed in the areas of optimizing switch shunt actions and coordinating all available resources to deal with uncertain patterns from increasing distributed renewable generation in the operational time frame. These topics are not deeply explored in the literature.

Power consumption analysis of constant bit rate data transmission over 3G mobile wireless networks

DEFF Research Database (Denmark)

Wang, Le; Ukhanova, Ann; Belyaev, Evgeny

2011-01-01

This paper presents the analysis of the power consumption of data transmission with constant bit rate over 3G mobile wireless networks. Our work includes the description of the transition state machine in 3G networks, followed by the detailed energy consumption analysis and measurement results...... of the radio link power consumption. Based on these description and analysis, we propose power consumption model. The power model was evaluated on the smartphone Nokia N900, which follows a 3GPP Release 5 and 6 supporting HSDPA/HSPA data bearers. Further we propose method of parameters selection for 3GPP...... transition state machine that allows to decrease power consumption on the mobile device....

Superconducting power transmission: the perils and promise

Energy Technology Data Exchange (ETDEWEB)

Forsyth, E B

1976-06-01

The development of bulk electricity transmission systems must be considered in the light of changing growth rates, increasing resistances to ehv overhead transmission and the tendency to concentrate generation in fewer sites. Helium-cooled or superconducting cables possess technical characteristics which will make them suitable as utility network components for power transmission over distances of ten to several hundred miles. These properties are illustrated by considering two applications in existing electrical networks. The first is a 43 mile system to transmit 4800 MVA and the second is a potential application under study in Pennsylvania to transmit 10,000 MVA over a distance of 350 miles or so. Helium-cooled versions of these transmission systems were designed to permit technical and economic evaluations. The major groups and institutions throughout the world engaged in the development of helium-cooled cables are listed and aspects of the technical approaches are briefly described.

Long distance transmission of bulk power: the EHV-UHV DC challenge

Energy Technology Data Exchange (ETDEWEB)

Clerici, A; Valtorta, G

1994-12-31

This paper deals with technical and economical analysis of transmission of powers in the range from 1000 to 5000 MW and distances included between 1000 to 4000 km. The advantages of adoption of UHV DC transmission are evident especially for the longest distances and the largest power levels considered. (author) 4 refs., 9 figs.

Use of FACTS for enhanced flexibility and efficiency in power transmission and distribution grids

Energy Technology Data Exchange (ETDEWEB)

Grunbaum, Rolf; Wahlberg, Conny; Sannino, Ambra

2010-09-15

The paper shows how the use of FACTS increases flexibility in power transmission and distribution, improving capacity of transmission corridors to integrate renewable power production. Examples included are 69 kV directly connected SVCs for grid stabilization in conjunction with a high degree of wind power penetration; series compensation to evacuate power from the largest wind power installation in USA; SVC to increase the reliability and reduce congestion over a heavily loaded power corridor; thyristor controlled series compensation to increase the dynamic stability and power transmission capability of a power inter-connector. Finally, some applications of Dynamic energy storage are highlighted.

Portable wireless power transmission system for video capsule endoscopy.

Science.gov (United States)

Zhiwei, Jia; Guozheng, Yan; Bingquan, Zhu

2014-10-01

Wireless power transmission is considered a practical way of overcoming the power shortage of wireless capsule endoscopy (VCE). However, most patients cannot tolerate the long hours of lying in a fixed transmitting coil during diagnosis. To develop a portable wireless power transmission system for VCE, a compact transmitting coil and a portable inverter circuit driven by rechargeable batteries are proposed. The couple coils, optimized considering the stability and safety conditions, are 28 turns of transmitting coil and six strands of receiving coil. The driven circuit is designed according to the portable principle. Experiments show that the integrated system could continuously supply power to a dual-head VCE for more than 8 h at a frame rate of 30 frames per second with resolution of 320 × 240. The portable VCE exhibits potential for clinical applications, but requires further improvement and tests.

Optimisation of VSC-HVDC Transmission for Wind Power Plants

DEFF Research Database (Denmark)

Silva, Rodrigo Da

Connection of Wind Power Plants (WPP), typically oshore, using VSCHVDC transmission is an emerging solution with many benefits compared to the traditional AC solution, especially concerning the impact on control architecture of the wind farms and the grid. The VSC-HVDC solution is likely to meet...... more stringent grid codes than a conventional AC transmission connection. The purpose of this project is to analyse how HVDC solution, considering the voltage-source converter based technology, for grid connection of large wind power plants can be designed and optimised. By optimisation, the project...... the robust control technique is applied is compared with the classical proportional-integral (PI) performance, by means of time domain simulation in a point-to-point HVDC connection. The three main parameters in the discussion are the wind power delivered from the offshore wind power plant, the variation...

Linking Up : Public-Private Partnerships in Power Transmission in Africa

OpenAIRE

World Bank

2017-01-01

The 'Linking up: Public-Private Partnerships in Power Transmission in Africa' report examines private sector-led investments in transmission globally and how this approach is applicable in sub-Saharan Africa. The private sector has invested over US$25 billion in the generation sector in Africa, and across other regions, has also participated successfully in transmission networks in many co...

Challenges facing the European power transmission tariffs: The case of inter-TSO compensation

International Nuclear Information System (INIS)

Stoilov, Dimo; Dimitrov, Yulian; Francois, Bruno

2011-01-01

This article draws attention to problems important for all EU power consumers-the unfairness in individual payments for power transmission and in the cross-border subsidy element in the mechanism of Inter-Transmission System Operators (TSO) Compensation (ITC). A brief review of power transmission tariffs brings out the structure of the problems. A short retrospection explains their growth. The essence of the ITC mechanism is explained and existing shortcomings are illustrated. The deficiencies of existing regulations for transmission pricing are analyzed. In the light of this analysis, the ITC problem is reconsidered and defined more precisely. The basic prerequisites to an ITC reformulation process are presented. The main principles of a new simple, transparent and equitable approach are suggested, in accordance with the contemporary legal positions and functions of the TSOs. - Highlights: → Investigations in the mechanism known as Inter-TSO Compensation (ITC). → Deficiencies in European regulations for cross-border power transmission payments. → Main principles of a new approach avoiding the existing cross-subsidies. → Appeal for reconsideration and a more precise definition of the ITC problem. → Public welfare enhancement by fairness in payment for power transmission.

Electricity market equilibrium model with resource constraint and transmission congestion

Energy Technology Data Exchange (ETDEWEB)

Gao, F. [ABB, Inc., Santa Clara, CA 95050 (United States); Sheble, G.B. [Portland State University, Portland, OR 97207 (United States)

2010-01-15

Electricity market equilibrium model not only helps Independent System Operator/Regulator analyze market performance and market power, but also provides Market Participants the ability to build optimal bidding strategies based on Microeconomics analysis. Supply Function Equilibrium (SFE) is attractive compared to traditional models and many efforts have been made on it before. However, most past research focused on a single-period, single-market model and did not address the fact that GENCOs hold a portfolio of assets in both electricity and fuel markets. This paper first identifies a proper SFE model, which can be applied to a multiple-period situation. Then the paper develops the equilibrium condition using discrete time optimal control considering fuel resource constraints. Finally, the paper discusses the issues of multiple equilibria caused by transmission network and shows that a transmission constrained equilibrium may exist, however the shadow price may not be zero. Additionally, an advantage from the proposed model for merchant transmission planning is discussed. (author)

Electricity market equilibrium model with resource constraint and transmission congestion

International Nuclear Information System (INIS)

Gao, F.; Sheble, G.B.

2010-01-01

Electricity market equilibrium model not only helps Independent System Operator/Regulator analyze market performance and market power, but also provides Market Participants the ability to build optimal bidding strategies based on Microeconomics analysis. Supply Function Equilibrium (SFE) is attractive compared to traditional models and many efforts have been made on it before. However, most past research focused on a single-period, single-market model and did not address the fact that GENCOs hold a portfolio of assets in both electricity and fuel markets. This paper first identifies a proper SFE model, which can be applied to a multiple-period situation. Then the paper develops the equilibrium condition using discrete time optimal control considering fuel resource constraints. Finally, the paper discusses the issues of multiple equilibria caused by transmission network and shows that a transmission constrained equilibrium may exist, however the shadow price may not be zero. Additionally, an advantage from the proposed model for merchant transmission planning is discussed. (author)

Three-Phase Time-Multiplexed Planar Power Transmission to Distributed Implants.

Science.gov (United States)

Lee, Byunghun; Ahn, Dukju; Ghovanloo, Maysam

2016-03-01

A platform has been presented for wireless powering of receivers (Rx's) that are arbitrarily distributed over a large area. A potential application could be powering of small Rx implants, distributed over large areas of the brain. The transmitter (Tx) consists of three overlapping layers of hexagonal planar spiral coils (hex-PSC) that are horizontally shifted to provide the strongest and most homogeneous electromagnetic flux coverage. The three-layer hex-PSC array is driven by a three-phase time-division-multiplexed power Tx that takes the advantage of the carrier phase shift, coil geometries, and Rx time constant to homogeneously power the arbitrarily distributed Rx's regardless of their misalignments. The functionality of the proposed three-phase power transmission concept has been verified in a detailed scaled-up high-frequency structure simulator Advanced Design System simulation model and measurement setup, and compared with a conventional Tx. The new Tx delivers 5.4 mW to each Rx and achieves, on average, 5.8% power transfer efficiency to the Rx at the worst case 90° angular misalignment, compared with 1.4% by the conventional Tx.

Study of a wireless power transmission system for an active capsule endoscope.

Science.gov (United States)

Xin, Wenhui; Yan, Guozheng; Wang, Wenxin

2010-03-01

An active capsule endoscope (ACE) will consume much more energy than can be power by batteries. Its orientation and position are always undetermined when it continues the natural way down the gastrointestinal track. In order to deliver stable and sufficient energy to ACE safely, a wireless power transmission system based on inductive coupling is presented. The system consists of a Helmholtz primary coil outside and a multiple secondary coils inside the body. The Helmholtz primary coil is driven to generate a uniform alternating magnetic field covering the whole of the alimentary tract, and the multiple secondary coils receive energy regardless of the ACE's position and orientation relative to the generated magnetic field. The human tissue safety of the electromagnetic field generated by transmitting coil was evaluated, based on a high-resolution realistic human model. At least 310 mW usable power can be transmitted under the worst geometrical conditions. Outer dimensions of the power receiver, 10 mm diameter x 12 mm; transmitting power, 25 W; resonant frequency, 400 kHz. The maximum specific absorption rate (SAR) and current density of human tissues are 0.329 W/kg and 3.82 A/m(2), respectively, under the basic restrictions of the International Commission on Non-ionizing Radiation Protection (ICNIRP). The designed wireless power transmission is shown to be feasible and potentially safe in a future application. (c) 2010 John Wiley & Sons, Ltd.

Risk Evaluation on UHV Power Transmission Construction Project Based on AHP and FCE Method

OpenAIRE

Huiru Zhao; Sen Guo

2014-01-01

Ultra high voltage (UHV) power transmission construction project is a high-tech power grid construction project which faces many risks and uncertainty. Identifying the risk of UHV power transmission construction project can help mitigate the risk loss and promote the smooth construction. The risk evaluation on “Zhejiang-Fuzhou” UHV power transmission construction project was performed based on analytic hierarchy process (AHP) and fuzzy comprehensive evaluation (FCE) method in this paper. Afte...

Electromagnetic Interference Issues of A Wireless Power Transmission Converter

DEFF Research Database (Denmark)

Khazraj, Hesam; Haji Bashi, Mazaher; Silva, Filipe Miguel Faria da

2018-01-01

field and the leakage current flowing through stray capacitors. In this paper, the EMI of wireless power transmission technology is highlighted and for the first time evaluated from a new perspective. The possible parasitic paths are identified simply. Additionally, effective high-frequency models......Many recent studies have focused on the inductive charging to transfer electrical power from a source to batteries without any electrical interface. The main problem with them is that inductive charging technologies may have electromagnetic compatibility (EMC) issues caused by the leakage magnetic...... for each part of the inductive charger are presented. At the first, the lowest EMI technology for wireless charging is chosen and simulated. To overcome the EMI and leakage current problems, this paper also suggests using a new passive EMI filter topology. Simulation results show the necessity...

MATL : Canada's first merchant power transmission interconnection : experiences and future outlook

International Nuclear Information System (INIS)

Wilson, L.

2006-01-01

The current status of the Montana Alberta Tie Ltd. (MATL) merchant transmission project was outlined with reference to the business concept, the advantages of the project and market opportunities. Some of the challenges facing the project were discussed along with lessons learned and accomplishments thus far. MATL is preparing to construct a privately funded transmission line between Lethbridge, Alberta and Great Falls, Montana. The project represents the first direct power transmission inter-connection between Montana and Alberta. The 346 km, 230 kV AC transmission line with phase shifting transformer and 300 MW transfer capacity will be a synchronous interconnection and will improve the reliability of the entire electric systems in both Montana and Alberta. The benefits of the interconnected power system include increased reliability and stability of the existing power grids; better import/export capabilities; more competition and options in the marketplace; greater flexibility in scheduling generator maintenance; and, optimal allocation of generation resources. tabs., figs

Hydraulic fluid used for power transmission

Energy Technology Data Exchange (ETDEWEB)

Heikkilae, M.; Pikulinsky, K.; Leisio, C.

1996-11-01

In early October another 50-kilowatt wind turbine was provided with new power transmission technology at the Kopparnaes Energy Park in Inkoo, Finland, west of Helsinki. The new technology is thought to make this wind turbine located on the south coast of Finland more efficient, lighter, and cheaper. Certain aspects of this new technology can be applied to older wind turbines. (orig.)

Northern States Power Company's open transmission tariff from a customer's perspective

International Nuclear Information System (INIS)

Marietta, K.E.; Achinger, S.K.

1993-01-01

In October of 1990, Northern States Power Company (NSP or Company), filed a unique open transmission tariff for both captive customers and through-system transactions. This is an important step towards expanding transmission services in the United States. Many individuals in the utility industry, who may be considering Imposing generation costs on transmission services, have been closely monitoring NSP's case which is currently before the Federal Energy Regulatory Commission (FERC). NSP's innovative generation costs include charges for reactive power production, frequency control, load dispatching, and load following. The results of this case may also have an important impact on the future of open transmission tariffs. Rates for these services depend on the customer's classification as either a captive or through-system consumer. The proposed tariff raises critical issues related to the costing of these transmission services. NSP's methodology has caused serious concern because the proposed tariff would increase transmission costs by an average of 53%. This paper will discuss the benefits of transmission, proposed rates, contract terms, and costing methodologies of NSP's plan

Power and signal transmission for mobile teleoperated systems

International Nuclear Information System (INIS)

Morris, A.C. Jr.; Hamel, W.R.

1986-01-01

Appropriate means must be furnished for supplying power and for sending controlling commands to mobile teleoperated systems. This paper describes a number of umbilical, onboard, and wireless systems used in transmitting power that are available for mobile teleoperator services. The pros and cons of selecting appropriate methods from a list of possible communication systems (wired, fiber optic, and radio frequency) are also examined. Moreover, hybrid systems combining wireless power transmissions with command-information signals are also possible. 20 refs., 6 figs., 1 tab

Evaluation of SAR in a human body model due to wireless power transmission in the 10 MHz band.

Science.gov (United States)

Laakso, Ilkka; Tsuchida, Shogo; Hirata, Akimasa; Kamimura, Yoshitsugu

2012-08-07

This study discusses a computational method for calculating the specific absorption rate (SAR) due to a wireless power transmission system in the 10 MHz frequency band. A two-step quasi-static method comprised of the method of moments and the scalar potential finite-difference method are proposed. The applicability of the quasi-static approximation for localized exposure in this frequency band is discussed by comparing the SAR in a lossy dielectric cylinder computed with a full-wave electromagnetic analysis and the quasi-static approximation. From the computational results, the input impedance of the resonant coils was affected by the existence of the cylinder. On the other hand, the magnetic field distribution in free space and considering the cylinder and an impedance matching circuit were in good agreement; the maximum difference in the amplitude of the magnetic field was 4.8%. For a cylinder-coil distance of 10 mm, the difference between the peak 10 g averaged SAR in the cylinder computed with the full-wave electromagnetic method and our quasi-static method was 7.8%. These results suggest that the quasi-static approach is applicable for conducting the dosimetry of wireless power transmission in the 10 MHz band. With our two-step quasi-static method, the SAR in the anatomically based model was computed for different exposure scenarios. From those computations, the allowable input power satisfying the limit of a peak 10 g averaged SAR of 2.0 W kg(-1) was 830 W in the worst case exposure scenario with a coil positioned at a distance of 30 mm from the chest.

A bi-level integrated generation-transmission planning model incorporating the impacts of demand response by operation simulation

International Nuclear Information System (INIS)

Zhang, Ning; Hu, Zhaoguang; Springer, Cecilia; Li, Yanning; Shen, Bo

2016-01-01

Highlights: • We put forward a novel bi-level integrated power system planning model. • Generation expansion planning and transmission expansion planning are combined. • The effects of two sorts of demand response in reducing peak load are considered. • Operation simulation is conducted to reflect the actual effects of demand response. • The interactions between the two levels can guarantee a reasonably optimal result. - Abstract: If all the resources in power supply side, transmission part, and power demand side are considered together, the optimal expansion scheme from the perspective of the whole system can be achieved. In this paper, generation expansion planning and transmission expansion planning are combined into one model. Moreover, the effects of demand response in reducing peak load are taken into account in the planning model, which can cut back the generation expansion capacity and transmission expansion capacity. Existing approaches to considering demand response for planning tend to overestimate the impacts of demand response on peak load reduction. These approaches usually focus on power reduction at the moment of peak load without considering the situations in which load demand at another moment may unexpectedly become the new peak load due to demand response. These situations are analyzed in this paper. Accordingly, a novel approach to incorporating demand response in a planning model is proposed. A modified unit commitment model with demand response is utilized. The planning model is thereby a bi-level model with interactions between generation-transmission expansion planning and operation simulation to reflect the actual effects of demand response and find the reasonably optimal planning result.

A Novel Oscillating Rectenna for Wireless Microwave Power Transmission

Science.gov (United States)

McSpadden, J. O.; Dickinson, R. M.; Fan, L.; Chang, K.

1998-01-01

A new concept for solid state wireless microwave power transmission is presented. A 2.45 GHz rectenna element that was designed for over 85% RF to dc power conversion efficiency has been used to oscillate at 3.3 GHz with an approximate 1% dc to RF conversion efficiency.

Acoustic Power Transmission Through a Ducted Fan

Science.gov (United States)

Envia, Ed

2016-01-01

For high-speed ducted fans, when the rotor flowfield is shock-free, the main contribution to the inlet radiated acoustic power comes from the portion of the rotor stator interaction sound field that is transmitted upstream through the rotor. As such, inclusion of the acoustic transmission is an essential ingredient in the prediction of the fan inlet noise when the fan tip relative speed is subsonic. This paper describes a linearized Euler based approach to computing the acoustic transmission of fan tones through the rotor. The approach is embodied in a code called LINFLUX was applied to a candidate subsonic fan called the Advanced Ducted Propulsor (ADP). The results from this study suggest that it is possible to make such prediction with sufficient fidelity to provide an indication of the acoustic transmission trends with the fan tip speed.

Link-state-estimation-based transmission power control in wireless body area networks.

Science.gov (United States)

Kim, Seungku; Eom, Doo-Seop

2014-07-01

This paper presents a novel transmission power control protocol to extend the lifetime of sensor nodes and to increase the link reliability in wireless body area networks (WBANs). We first experimentally investigate the properties of the link states using the received signal strength indicator (RSSI). We then propose a practical transmission power control protocol based on both short- and long-term link-state estimations. Both the short- and long-term link-state estimations enable the transceiver to adapt the transmission power level and target the RSSI threshold range, respectively, to simultaneously satisfy the requirements of energy efficiency and link reliability. Finally, the performance of the proposed protocol is experimentally evaluated in two experimental scenarios-body posture change and dynamic body motion-and compared with the typical WBAN transmission power control protocols, a real-time reactive scheme, and a dynamic postural position inference mechanism. From the experimental results, it is found that the proposed protocol increases the lifetime of the sensor nodes by a maximum of 9.86% and enhances the link reliability by reducing the packet loss by a maximum of 3.02%.

Point-to-point microwave power transmission experiment; Maikuroha ni yoru denryoku yuso no kiso kenkyu

Energy Technology Data Exchange (ETDEWEB)

Shimokura, N.; Kirihara, T. [Kansai Electric Power Co. Inc., Osaka (Japan)

1997-09-30

In order to demonstrate the power transmission using microwave and arrange advantages and problems in the wireless power transmission, field tests of point-to-point power transmission were conducted. Microwave frequency of 2.45 GHz was used, which is assigned as the industrial, scientific and medical frequency. The transmission system is composed of generator, director tube, primary radiator, and transmission antenna. The maximum 5 kW of microwave power can be transmitted by combining a 3 m-diameter parabolic antenna and a magnetron. The receiving system is composed of devices called as RECTENNA (rectifying antenna). A large capacity and high efficiency RECTENNA was developed, by which the maximum 2.5 W of input power per single device can be provided. As a result of the experiments, efficiency at the transmission side was over 70%, and RF-DC efficiency at the receiving side was about 51%. At the open-air test site, however, the total efficiency of only 14.8% could be obtained. 8 refs., 12 figs.

Case study on the US superconducting power transmission program

Energy Technology Data Exchange (ETDEWEB)

Hammel, E.F.

1996-02-01

After the 1911 discovery of superconductivity (the abrupt loss of electrical resistance in certain materials at very low temperatures), attempts were made to make practical use of this phenomenon. Initially these attempts failed, but in the early 1960s (after 50 years of research) they succeeded. By then, the projected growth in the production and consumption of electrical energy required much higher capacity power transmission capabilities than were available or likely to become available from incremental improvements in existing transmission technology. Since superconductors were capable in principle of transmitting huge amounts of power, research programs to develop and demonstrate superconducting transmission lines were initiated in the US and abroad. The history of the US program, including the participants, their objectives, funding and progress made, is outlined. Since the R&D program was terminated before the technology was completely demonstrated, the reasons for and consequences of this action are discussed in a final section.

Wind power development in the United States: Effects of policies and electricity transmission congestion

Science.gov (United States)

Hitaj, Claudia

In this dissertation, I analyze the drivers of wind power development in the United States as well as the relationship between renewable power plant location and transmission congestion and emissions levels. I first examine the role of government renewable energy incentives and access to the electricity grid on investment in wind power plants across counties from 1998-2007. The results indicate that the federal production tax credit, state-level sales tax credit and production incentives play an important role in promoting wind power. In addition, higher wind power penetration levels can be achieved by bringing more parts of the electricity transmission grid under independent system operator regulation. I conclude that state and federal government policies play a significant role in wind power development both by providing financial support and by improving physical and procedural access to the electricity grid. Second, I examine the effect of renewable power plant location on electricity transmission congestion levels and system-wide emissions levels in a theoretical model and a simulation study. A new renewable plant takes the effect of congestion on its own output into account, but ignores the effect of its marginal contribution to congestion on output from existing plants, which results in curtailment of renewable power. Though pricing congestion removes the externality and reduces curtailment, I find that in the absence of a price on emissions, pricing congestion may in some cases actually increase system-wide emissions. The final part of my dissertation deals with an econometric issue that emerged from the empirical analysis of the drivers of wind power. I study the effect of the degree of censoring on random-effects Tobit estimates in finite sample with a particular focus on severe censoring, when the percentage of uncensored observations reaches 1 to 5 percent. The results show that the Tobit model performs well even at 5 percent uncensored observations

A Reduced Wind Power Grid Model for Research and Education

Energy Technology Data Exchange (ETDEWEB)

Akhmatov, V. [Energinet.dk, Fjordvejen 1-11, DK-7000 Fredericia (Denmark); Lund, T.; Hansen, A.D.; Sorensen, P.E. [Risoe National Laboratory, DK-4000 Roskilde (Denmark); Nielsen, A.H. [Centre for Electric Technology, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark)

2006-07-01

A reduced grid model of a transmission system with a number of central power plants, consumption centers, local wind turbines and a large offshore wind farm is developed and implemented in the simulation tool PowerFactory (DIgSILENT). The reduced grid model is given by Energinet.dk, Transmission System Operator of Denmark (TSO) for Natural Gas and Electricity, to the Danish Universities and the Risoe National Laboratory. Its intended usage is education and studying of interaction between electricity-producing wind turbines and a realistic transmission system. Focus in these studies is on voltage stability issues and on the ride-through capability of different wind turbine concepts, equipped with advanced controllers, developed by the Risoe National Laboratory.

Three-dimensional electromagnetic model of the pulsed-power Z-pinch accelerator

Directory of Open Access Journals (Sweden)

D. V. Rose

2010-01-01

Full Text Available A three-dimensional, fully electromagnetic model of the principal pulsed-power components of the 26-MA ZR accelerator [D. H. McDaniel et al., in Proceedings of the 5th International Conference on Dense Z-Pinches (AIP, New York, 2002, p. 23] has been developed. This large-scale simulation model tracks the evolution of electromagnetic waves through the accelerator’s intermediate-storage capacitors, laser-triggered gas switches, pulse-forming lines, water switches, triplate transmission lines, and water convolute to the vacuum insulator stack. The insulator-stack electrodes are coupled to a transmission-line circuit model of the four-level magnetically insulated vacuum-transmission-line section and double-post-hole convolute. The vacuum-section circuit model is terminated by a one-dimensional self-consistent dynamic model of an imploding z-pinch load. The simulation results are compared with electrical measurements made throughout the ZR accelerator, and are in good agreement with the data, especially for times until peak load power. This modeling effort demonstrates that 3D electromagnetic models of large-scale, multiple-module, pulsed-power accelerators are now computationally tractable. This, in turn, presents new opportunities for simulating the operation of existing pulsed-power systems used in a variety of high-energy-density-physics and radiographic applications, as well as even higher-power next-generation accelerators before they are constructed.

Wireless (Power Transfer Transmission of Electrical Energy (Electricity Intended for Consumer Purposes up to 50 W

Directory of Open Access Journals (Sweden)

Marek Piri

2016-01-01

Full Text Available This project deals with Power Semiconductor Systems PSS for wireless transmission of electricity to the power of 50~W with regard to the distance and transmission efficiency. We decided to use electromagnetic resonance for electrical energy transmission. For experimental verification, we have wound two coils of identical dimensions. At a given power transmission solutions, we obtain the highest efficiency η = 70% at a distance of 5 cm, where the transmitted power was 48 W.

Optimized transmission-line impedance transformers for petawatt-class pulsed-power accelerators

Directory of Open Access Journals (Sweden)

D. R. Welch

2008-03-01

Full Text Available We have developed 1D analytic and 2D fully electromagnetic models of radial transmission-line impedance transformers. The models have been used to quantify the power-transport efficiency and pulse sharpening of such transformers as a function of voltage pulse width and impedance profile. For the cases considered, we find that in the limit as Γ→0 (where Γ is the ratio of the pulse width to the one-way transit time of the transformer, the transport efficiency is maximized when the impedance profile is exponential. As Γ increases from zero, the optimum profile gradually deviates from an exponential. A numerical procedure is presented that determines the optimum profile for a given pulse shape and width. The procedure can be applied to optimize the design of impedance transformers used in petawatt-class pulsed-power accelerators.

Modular VSC converter based HVDC power transmission from offshore wind power plant: Compared to the conventional HVAC system

DEFF Research Database (Denmark)

Sharma, Ranjan; Rasmussen, Tonny Wederberg; Jensen, Kim Høj

2010-01-01

power transmission options with HVDC systems are under consideration. In this paper, a comparison between a conventional HVAC transmission system and a HVDC system equipped with modular voltage source converters is provided. The comparison is based on the total energy transmission capability...

Analytical Model for High Impedance Fault Analysis in Transmission Lines

Directory of Open Access Journals (Sweden)

S. Maximov

2014-01-01

Full Text Available A high impedance fault (HIF normally occurs when an overhead power line physically breaks and falls to the ground. Such faults are difficult to detect because they often draw small currents which cannot be detected by conventional overcurrent protection. Furthermore, an electric arc accompanies HIFs, resulting in fire hazard, damage to electrical devices, and risk with human life. This paper presents an analytical model to analyze the interaction between the electric arc associated to HIFs and a transmission line. A joint analytical solution to the wave equation for a transmission line and a nonlinear equation for the arc model is presented. The analytical model is validated by means of comparisons between measured and calculated results. Several cases of study are presented which support the foundation and accuracy of the proposed model.

Solar-pumped lasers for space power transmission

Science.gov (United States)

Taussig, R.; Bruzzone, C.; Nelson, L.; Quimby, D.; Christiansen, W.

1979-01-01

Multi-Megawatt CW solar-pumped lasers appear to be technologically feasible for space power transmission in the 1990s time frame. A new concept for a solar-pumped laser is presented which utilizes an intermediate black body cavity to provide a uniform optical pumping environment for the lasant, either CO or CO2. Reradiation losses are minimized with resulting high efficiency operation. A 1 MW output laser may weigh as little as 8000 kg including solar collector, black body cavity, laser cavity and ducts, pumps, power systems and waste heat radiator. The efficiency of such a system will be on the order of 10 to 20%. Details of the new concept, laser design, comparison to competing solar-powered lasers and applications to a laser solar power satellite (SPS) concept are presented.

Micro-size antenna structure with vertical nanowires for wireless power transmission and communication.

Science.gov (United States)

Kang, Jong-Gu; Jeong, Yeri; Shin, Jeong Hee; Choi, Ji-Woong; Sohn, Jung Inn; Cha, Seung Nam; Jang, Jae Eun

2014-11-01

For biomedical implanted devices, a wireless power or a signal transmission is essential to protect an infection and to enhance durability. In this study, we present a magnetic induction technique for a power transmission without any wire connection between transmitter (Tx) and receiver (Rx) in a micro scale. Due to a micro size effect of a flat spiral coil, a magnetic inductance is not high. To enhance the magnetic inductance, a three dimensional magnetic core is added to an antenna structure, which is consisted of ZnO nano wires coated by a nickel (Ni) layer. ZnO nano wires easily supply a large effective surface area with a vertical structural effect to the magnetic core structure, which induces a higher magnetic inductance with a ferro-magnetic material Ni. The magnetic induction antenna with the magnetic core shows a high inductance value, a low reflection power and a strong power transmission. The power transmission efficiencies are tested under the air and the water medium are almost the same values, so that the magnetic induction technique is quite proper to body implanted systems.

Power transmission cable development for the Space Station Freedom electrical power system

Science.gov (United States)

Schmitz, Gregory V.; Biess, John J.

1989-01-01

Power transmission cable is presently being evaluated under a NASA Lewis Research Center advanced development contract for application in the Space Station Freedom (SSF) electrical power system (EPS). Evaluation testing has been performed by TRW and NASA Lewis Research Center. The results of this development contract are presented. The primary cable design goals are to provide (1) a low characteristic inductance to minimize line voltage drop at 20 kHz, (2) electromagnetic compatibility control of the 20-kHz ac power current, (3) a physical configuration that minimizes ac resistance and (4) release of trapped air for corona-free operation.

Comparison of Transmission Line Methods for Surface Acoustic Wave Modeling

Science.gov (United States)

Wilson, William; Atkinson, Gary

2009-01-01

Surface Acoustic Wave (SAW) technology is low cost, rugged, lightweight, extremely low power and can be used to develop passive wireless sensors. For these reasons, NASA is investigating the use of SAW technology for Integrated Vehicle Health Monitoring (IVHM) of aerospace structures. To facilitate rapid prototyping of passive SAW sensors for aerospace applications, SAW models have been developed. This paper reports on the comparison of three methods of modeling SAWs. The three models are the Impulse Response Method (a first order model), and two second order matrix methods; the conventional matrix approach, and a modified matrix approach that is extended to include internal finger reflections. The second order models are based upon matrices that were originally developed for analyzing microwave circuits using transmission line theory. Results from the models are presented with measured data from devices. Keywords: Surface Acoustic Wave, SAW, transmission line models, Impulse Response Method.

A literature survey on asset management in electrical power [transmission and distribution] system

OpenAIRE

Khuntia, S.R.; Rueda Torres, José L.; Bouwman, S.; van der Meijden, M.A.M.M.

2016-01-01

Asset management is one of the key components in a transforming electric power industry. Electric power industry is undergoing significant changes because of technical, socio-economical and environmental developments. Also, because of restructuring and deregulation, the focus has been on transmission and distribution assets that include transmission lines, power transformers, protection devices, substation equipment and support structures. This study aims to provide a detailed exposure to ass...

Evaluation of SAR in a human body model due to wireless power transmission in the 10 MHz band

International Nuclear Information System (INIS)

Laakso, Ilkka; Tsuchida, Shogo; Hirata, Akimasa; Kamimura, Yoshitsugu

2012-01-01

This study discusses a computational method for calculating the specific absorption rate (SAR) due to a wireless power transmission system in the 10 MHz frequency band. A two-step quasi-static method comprised of the method of moments and the scalar potential finite-difference method are proposed. The applicability of the quasi-static approximation for localized exposure in this frequency band is discussed by comparing the SAR in a lossy dielectric cylinder computed with a full-wave electromagnetic analysis and the quasi-static approximation. From the computational results, the input impedance of the resonant coils was affected by the existence of the cylinder. On the other hand, the magnetic field distribution in free space and considering the cylinder and an impedance matching circuit were in good agreement; the maximum difference in the amplitude of the magnetic field was 4.8%. For a cylinder–coil distance of 10 mm, the difference between the peak 10 g averaged SAR in the cylinder computed with the full-wave electromagnetic method and our quasi-static method was 7.8%. These results suggest that the quasi-static approach is applicable for conducting the dosimetry of wireless power transmission in the 10 MHz band. With our two-step quasi-static method, the SAR in the anatomically based model was computed for different exposure scenarios. From those computations, the allowable input power satisfying the limit of a peak 10 g averaged SAR of 2.0 W kg −1 was 830 W in the worst case exposure scenario with a coil positioned at a distance of 30 mm from the chest. (paper)

Impacts on investments, and transmission/distribution loss through power sector reforms

International Nuclear Information System (INIS)

Nagayama, Hiroaki

2010-01-01

This study analyses original panel data from 86 countries between 1985 and 2006. Econometric methods were used to identify the effects of different policy devices of power sector reforms on performance indicators (installed capacity per capita, transmission and distribution loss) in the countries analyzed. The research findings suggest that reform variables such as the entry of independent power producers (IPPs), unbundling of generation and transmission, establishment of regulatory agencies, and the introduction of a wholesale spot market are the driving forces of increasing generation capacity, as well as reducing transmission and distribution loss in the respective regions. In this study, we can assume that, firstly, different electric industry's reform policies/measures have different impacts on geographically and economically diverse countries. Secondly, a country's state of economic development has a different impact on policy effects of reforms. Thirdly, coexistent with independent regulatory agencies, reform policy becomes more powerful in realizing sector performances.

Evaluation of a microwave high-power reception-conversion array for wireless power transmission

Science.gov (United States)

Dickinson, R. M.

1975-01-01

Initial performance tests of a 24-sq m area array of rectenna elements are presented. The array is used as the receiving portion of a wireless microwave power transmission engineering verification test system. The transmitting antenna was located at a range of 1.54 km. Output dc voltage and power, input RF power, efficiency, and operating temperatures were obtained for a variety of dc load and RF incident power levels at 2388 MHz. Incident peak RF intensities of up to 170 mW/sq cm yielded up to 30.4 kW of dc output power. The highest derived collection-conversion efficiency of the array was greater than 80 percent.

A wireless power transmission system for an active capsule endoscope for colon inspection.

Science.gov (United States)

Jia, Zhiwei; Yan, Guozheng; Shi, Yu; Zhu, Bingquan

2012-07-01

Multipurpose active capsule endoscopes (ACE) have drawn considerable attention in recent years, but these devices continue to suffer from energy limitations. In order to deliver stable and sufficient energy safely, a wireless power transmission system based on inductive coupling is presented. The system consists of a double-layer solenoid pair primary coil outside and a multiple secondary coils inside the body. At least 500 mW usable power can be transmitted under the worst geometrical conditions and the safety restraints in a volume of Φ13 × 13 mm. The wireless power transmission system is integrated to an ACE and applied in animal experiments. The designed wireless power transmission is proved to be feasible and potentially safe in a future application.

Mechanical Implementation and Simulation of MoboLab, A Mobile Robot for Inspection of Power Transmission Lines

Directory of Open Access Journals (Sweden)

Mahmud Saadat Foumani

2008-11-01

Full Text Available This paper describes the first phase in development of a mobile robot that can navigate aerial power transmission lines completely unattended by human operator. Its ultimate purpose is to automate inspection of power transmission lines and their equipments. The authors have developed a scaled functional model of such a mobile robot with a preliminary simple computer based on-off controller. MoboLab (Mobile Laboratory navigates a power transmission line between two strain towers. It can maneuver over obstructions created by line equipments such as insulators, warning spheres, dampers, and spacer dampers. It can also easily negotiate the towers by its three flexible arms. MoboLab has an internal main screw which enables the robot to move itself or its two front and rear arms independently through changing gripped points. When the front arm gets close to an obstacle, the arm detaches from the line and goes down, the robot moves forward, the arm passes the obstacle and grippes the line again. In a same way another arms pass the obstacle.

Magnet Lattice Design for the Transmission of Power Using Particle Beams

Energy Technology Data Exchange (ETDEWEB)

Marley, Daniel; /North Carolina State U. /SLAC

2012-08-24

As the amount of electricity generated by renewable energy sources continues to increase, the current method of power transmission will not serve as an adequate method for transmitting power over very long distances. A new method for transmitting power is proposed using particle beams in a storage ring. Particle beams offer an incredibly energy efficient alternative to transmission lines in transmitting power over very long distances. A thorough investigation of the magnet lattice design for this storage ring is presented. The design demonstrates the ability to design a ring with stable orbits over a 381.733 km circumference. Double bend achromats and FODO cells are implemented to achieve appropriate {beta} functions and dispersion functions for 9-11 GeV electron beams.

[A wireless power transmission system for capsule endoscope].

Science.gov (United States)

Xin, Wenhui; Yan, Guozheng; Wang, Wenxing

2010-06-01

In order to deliver power to the capsule endoscope, whose position and orientation are always changing when traveling along the alimentary tract, a wireless power transmission system based on electromagnetic coupling was proposed. The system is composed of Helmholtz transmitting coil and three-dimensional receiving coil. Helmholtz coil outside the body generates a uniform magnetic field covering the whole alimentary tract; three-dimensional coil inside retrieves stable power regardless of its position and orientation. The transmitter and receiver were designed and implemented, and the experiments validated the feasibility of the system. The results show that at least 320 mW of usable power can be transmitted to capsule endoscope when its position and orientation are changing at random and the transmitting power is 25W.

9{sup th} international workshop on large-scale integration of wind power into power systems as well as on transmission networks for offshore wind power plants. Proceedings

Energy Technology Data Exchange (ETDEWEB)

Betancourt, Uta; Ackermann, Thomas (eds.)

2010-07-01

Within the 9th International Workshop on large-scale integration of wind power into power systems as well as on transmission networks for offshore wind power plants at 18th to 19th October, 2010 in Quebec (Canada), lectures and poster papers were presented to the following themes: (1) Keynote session and panel; (2) European grid integration studies; (3) Modeling; (4) Wind forecasting; (5) North American grid integration studies; (6) Voltage stability and control; (7) Grid codes and impact studies; (8) Canadian University research (WESNet); (9) Operation and dispatch; (9) Offshore wind power plants; (10) Frequency Control; (11) Methodologies to estimate wind power impacts on power systems, summaries from IEAWIND collaboration; (12) HVDC; (13) Grid codes and system impact studies; (14) Modeling and validation; (15) Regulations, markets and offshore wind energy; (16) Integration issues; (17) Wind turbine control system; (18) Energy management and IT solutions.

LSコイルを用いたWireless Power Transmission

OpenAIRE

吉川, 隆; 更谷, 翔太

2014-01-01

The wireless power transmission is widely studied for many kinds of application, for example, power supply for cell phone or power source of EV. The supplying power of those applications is always over mW. But it is impossible to transmit for longer distance under the index of regulation of protection from radiofrequency electromagnetic field. Then many of such applications are considered with restriction of narrow area. Then we have surveyed low power demanding application the suitable appl...

Research on investment decisions model of trans-regional transmission network based on the theory of NPV

Science.gov (United States)

Zai, Wenjiao; Wang, Bo; Liu, Jichun; Shi, Haobo; Zeng, Pingliang

2018-02-01

The investment decision model of trans-regional transmission network in the context of Global Energy Internet was studied in this paper. The key factors affecting the trans-regional transmission network investment income: the income tax rate, the loan interest rate, the expected return on investment of the investment subject, the per capita GDP and so on were considered in the transmission network investment income model. First, according to the principle of system dynamics, the causality diagram of key factors was constructed. Then, the dynamic model of transmission investment decision was established. A case study of the power transmission network between China and Mongolia, through the simulation of the system dynamic model, the influence of the above key factors on the investment returns was analyzed, and the feasibility and effectiveness of the model was proved.

Transmission capacity and market power: the effect on a dominant generation firm

International Nuclear Information System (INIS)

Quick, David M.; Carey, Janis M.

2002-01-01

We examine the effect of transmission on a firm's market power by analyzing the optimal dispatch for a dominant firm in a short-run regional electricity generation market. Application of our research to Colorado shows that the dominant firm can strategically congest transmission into the region to receive a maximum price 54.9% of the time. When it does not get the maximum price, the dominant firm can receive an 11.6% average markup over the competitive price. We show how the threat of entry across an enhanced transmission grid can increase competition and limit market power in Colorado. (Author)

Real option valuation of power transmission investments by stochastic simulation

International Nuclear Information System (INIS)

Pringles, Rolando; Olsina, Fernando; Garcés, Francisco

2015-01-01

Network expansions in power markets usually lead to investment decisions subject to substantial irreversibility and uncertainty. Hence, investors need valuing the flexibility to change decisions as uncertainty unfolds progressively. Real option analysis is an advanced valuation technique that enables planners to take advantage of market opportunities while preventing or mitigating losses if future conditions evolve unfavorably. In the past, many approaches for valuing real options have been developed. However, applying these methods to value transmission projects is often inappropriate as revenue cash flows are path-dependent and affected by a myriad of uncertain variables. In this work, a valuation technique based on stochastic simulation and recursive dynamic programming, called Least-Square Monte Carlo, is applied to properly value the deferral option in a transmission investment. The effect of option's maturity, the initial outlay and the capital cost upon the value of the postponement option is investigated. Finally, sensitivity analysis determines optimal decision regions to execute, postpone or reject the investment projects. - Highlights: • A modern investment appraisal method is applied to value power transmission projects. • The value of the option to postpone decision to invest in transmission projects is assessed. • Simulation methods are best suited for valuing real options in transmission investments

Normalized power transmission between ABP and ICP in TBI.

Science.gov (United States)

Shahsavari, S; Hallen, T; McKelvey, T; Ritzen, C; Rydenhag, B

2009-01-01

A new approach to study the pulse transmission between the cerebrovascular bed and the intracranial space is presented. In the proposed approach, the normalized power transmission between ABP and ICP has got the main attention rather than the actual power transmission. Evaluating the gain of the proposed transfer function at any single frequency can reveal how the percentage of contribution of that specific frequency component has been changed through the cerebrospinal system. The gain of the new transfer function at the fundamental cardiac frequency was utilized to evaluate the state of the brain in three TBI patients. Results were assessed using the reference evaluations achieved by a novel CT scan-based scoring scheme. In all three study cases, the gain of the transfer function showed a good capability to follow the trend of the CT scores and describe the brain state. Comparing the new transfer function with the traditional one and also the index of compensatory reserve, the proposed transfer function was found more informative about the state of the brain in the patients under study.

A Study on the Application for Enhancing the Transmission Capability of the KEPCO Power System

Energy Technology Data Exchange (ETDEWEB)

Kim, Young Han; Kwon, Tea Won; Whang, Jong Young; Lee, Gun Joon; Kim, Tae Hoon; Chang, Byung Hoon; Min, Wan Ki [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Park, Young Moon; Park, Jong Gun [Seoul National University, Seoul (Korea, Republic of); Kim, Gun Joong [Chungnam National University, Taejon (Korea, Republic of); Oh, Tae Kwu; Choi, Kwu Hyung [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

1996-12-31

Investigation of stability for power system in 2000 year and 2006 year by using the analysis of real power system. Comparative investigation of the conventional transmission line upgrading methods such as HVDC, HOP, new conductor scheme. Investigation of FACTS, the recent transmission line upgrading method, with respect to the aspect of technique and cost and effect analysis when this method is applied to real power system. Development of the evaluation method of transmission type that should be considered when above method is applied to real power system with respect to aspect of technique and cost. Development of a long-range plan for the transmission capacity upgrading and the evaluation method of reliability. (author).

Comprehensive Benefit Evaluation of the Wind-PV-ES and Transmission Hybrid Power System Consideration of System Functionality and Proportionality

Directory of Open Access Journals (Sweden)

Huizheng Ji

2017-01-01

Full Text Available In the background of decreasing fossil fuels and increasing environmental pollution, the wind-photovoltaic energy storage and transmission hybrid power system (or called the wind-PV-ES and transmission hybrid system has become a strategic choice to achieve energy sustainability. However, the comprehensive benefit evaluation of such a combined power system is in a relatively blank state in China, which will hinder the reasonable and orderly development of this station. Four parts, the technical performance, economic benefit, ecological impact and social benefit, are considered in this paper, and a multi-angle evaluation index system of the wind-PV-ES and transmission system is designed. The projection pursuit model is used to evaluated system functionality conventionally; relative entropy theory is used to evaluate the system functionality simultaneously; and a comprehensive benefit evaluation model of the technique for order preference by similar to ideal solution (TOPSIS considering both system functionality and proportionality is constructed. Finally, the national demonstration station of the wind-PV-ES-transmission system is taken as an example to testify to the practicability and validity of the evaluation index system and model.

Seismic Response of Power Transmission Tower-Line System Subjected to Spatially Varying Ground Motions

Directory of Open Access Journals (Sweden)

Li Tian

2010-01-01

Full Text Available The behavior of power transmission tower-line system subjected to spatially varying base excitations is studied in this paper. The transmission towers are modeled by beam elements while the transmission lines are modeled by cable elements that account for the nonlinear geometry of the cables. The real multistation data from SMART-1 are used to analyze the system response subjected to spatially varying ground motions. The seismic input waves for vertical and horizontal ground motions are also generated based on the Code for Design of Seismic of Electrical Installations. Both the incoherency of seismic waves and wave travel effects are accounted for. The nonlinear time history analytical method is used in the analysis. The effects of boundary conditions, ground motion spatial variations, the incident angle of the seismic wave, coherency loss, and wave travel on the system are investigated. The results show that the uniform ground motion at all supports of system does not provide the most critical case for the response calculations.

SELF: expert system for supporting verification of network operating constraints in power transmission planning

Energy Technology Data Exchange (ETDEWEB)

Cicoria, R; Migliardi, P [Ente Nazionale per l` Energia Elettrica, Milan (Italy); Pogliano, P [Centro Informazioni Studi Esperienze (CISE), Milan (Italy)

1995-06-01

Performing planned studies into very large HV transmission systems is a very complex task which requires the use of simulation models and the application of the heuristic acquired by expert palnners during previous studies. The ENEL Electric Research Center and the CISE Artificial Intelligence Section have developed a knowledge-based system, named SELF, which is aimed at supporting the transmission system palnner. SELF is capable of assisting the engineer both in finding the convergence of the load flow calculation and determining solutions that respect active power, voltage and VAR operating constraints. This paper describes the overall architecture of the system and shows its integration in a larger planning environment called SPIRA, currently utilized at ENEL. More details are given on the least completed modules, the redispatching and network reinforcement subsystems which deal with active power constraint verification.

Transmission media appropriate laser-microwave solar power satellite system

Science.gov (United States)

Schäfer, C. A.; Gray, D.

2012-10-01

As a solution to the most critical problems with Solar power Satellite (SPS) development, a system is proposed which uses laser power transmission in space to a receiver high in the atmosphere that relays the power to Earth by either cable or microwave power transmission. It has been shown in the past that such hybrid systems have the advantages of a reduction in the mass of equipment required in geostationary orbit and avoidance of radio frequency interference with other satellites and terrestrial communications systems. The advantage over a purely laser power beam SPS is that atmospheric absorption is avoided and outages due to clouds and precipitation will not occur, allowing for deployment in the equatorial zone and guaranteeing year round operation. This proposal is supported by brief literature surveys and theoretical calculations to estimate crucial parameters in this paper. In relation to this concept, we build on a recently proposed method to collect solar energy by a tethered balloon at high altitude because it enables a low-cost start for bringing the first Watt of power to Earth giving some quick return on investment, which is desperately missing in the traditional SPS concept. To tackle the significant problem of GW-class SPSs of high launch cost per kg mass brought to space, this paper introduces a concept which aims to achieve a superior power over mass ratio compared to traditional satellite designs by the use of thin-film solar cells combined with optical fibres for power delivery. To minimise the aperture sizes and cost of the transmitting and receiving components of the satellite and high altitude receiver, closed-loop laser beam pointing and target tracking is crucial for pointing a laser beam onto a target area that is of similar size to the beam's diameter. A recently developed technique based on optical phase conjugation is introduced and its applicability for maintaining power transmission between the satellite and high altitude receiver is

Electric power transmission for a Hanford Nuclear Energy Center (HNEC)

International Nuclear Information System (INIS)

1975-09-01

The major issues examined in the comparison of the DIST and HNEC transmission concepts are: (1) type of transmission to be employed and an assessment of its technical feasibility, (2) availability of rights-of-way, (3) economics, (4) environmental impact, and (5) overall reliability of the transmission system. The type of transmission selected for bulk power transfer from an HNEC for the time period studied is overhead AC, 500 kV double or single circuit, a voltage currently used in the PNW system. This type of system can accommodate growth up to at least 23,000 MW of thermal capacity at an HNEC. Significant additional transmountain capacity needs would require 1100 kV transmission, which should be technologically proved by the end of the 1970s. (auth)

Power and signal transmission for mobile teleoperated systems

International Nuclear Information System (INIS)

Morris, A.C. Jr.; Hamel, W.R.

1985-01-01

Appropriate means must be furnished for supplying power and for sending controlling commands to mobile teleoperated systems. Because a sizable number of possibilities are available for such applications, methods used in designing both the power and communications systems built into mobile vehicles that serve in radiological emergencies must be carefully selected. This paper describes a number of umbilical, on-board, and wireless systems used in tranmitting power that are available for mobile teleoperator services. The pros and cons of selecting appropriate methods from a list of possible communication systems (wired, fiber optic, and radio frequency) are also examined. Moreover, hybrid systems combining wireless power transmissions with command-information signals are also possible

Wireless Power Transmission to Organic Light Emitting Diode Lighting Panel with Magnetically Coupled Resonator

Science.gov (United States)

Kim, Yong-Hae; Han, Jun-Han; Kang, Seung-Youl; Cheon, Sanghoon; Lee, Myung-Lae; Ahn, Seong-Deok; Zyung, Taehyoung; Lee, Jeong-Ik; Moon, Jaehyun; Chu, Hye Yong

2012-09-01

We are successful to lit the organic light emitting diode (OLED) lighting panel through the magnetically coupled wireless power transmission technology. For the wireless power transmission, we used the operation frequency 932 kHz, specially designed double spiral type transmitter, small and thin receiver on the four layered printed circuit board, and schottky diodes for the full bridge rectifier. Our white OLED is a hybrid type, in which phosphorescent and fluorescent organics are used together to generate stable white color. The total efficiency of power transmission is around 72%.

Development of a model for integrated simulation of the European transmission networks and electricity markets

International Nuclear Information System (INIS)

Rathke, Christian

2013-01-01

The liberalisation of electricity markets and the increase of renewable energy generation actually causes dramatic changes for the whole European power industry. The transmission system operators in particular have to meet the challenge to ensure a stable and reliable system operation in the future. Significant changes in power generation will require a substantial extension to current inadequate original transmission grids to handle increased wide area power flows. This is the only way to avoid overloading the grid and to reduce the herefrom resulting limitations for the Pan-European cross-border trade of electricity. This work describes in detail the development of a Pan-European integrated grid and an electricity market simulation tool. For this purpose an overview about the today's structure of the European electricity industry is given initially. Afterwards the configuration of the transmission grid, the used equipment and different methods for the load flow and short circuit calculation are explained. Furthermore models for the calculation of local loads and the power plant dispatch are presented in the following chapters. Following on from this a detailed model of the European electricity industry is developed and the main functions are described by means of some exemplary simulations. The simulation tool developed in this work enables the user to calculate realistic power plant schedules and the consequent resulting physical effects on the European transmission grid. It combines a time series based simulation of the electricity market with a detailed model of the transmission grid. The highly detailing of the model offers the feasibility to execute a complete AC load flow calculation using the Newton Raphson algorithm.Therefore it is possible to identify the active as well as the reactive power flows in the grid. The results of the power flow calculation are the basis for further investigations (e. g. the short circuit calculation) and to decide on

Losses at magnetic nulls in pulsed-power transmission line systems

International Nuclear Information System (INIS)

Mendel, C.W. Jr.; Pointon, T.D.; Savage, M.E.; Seidel, D.B.; Magne, I.; Vezinet, R.

2006-01-01

Pulsed-power systems operating in the terawatt regime must deal with large electron flows in vacuum transmission lines. In most parts of these transmission lines the electrons are constrained by the self-magnetic field to flow parallel to the conductors. In very low impedance systems, such as those used to drive Z-pinch radiation sources, the currents from multiple transmission lines are added together. This addition necessarily involves magnetic nulls that connect the positive and negative electrodes. The resultant local loss of magnetic insulation results in electron losses at the anode in the vicinity of the nulls. The lost current due to the magnetic null might or might not be appreciable. In some cases the lost current due to the null is not large, but is spatially localized, and may create a gas and plasma release from the anode that can lead to an excessive loss, and possibly to catastrophic damage to the hardware. In this paper we describe an analytic model that uses one geometric parameter (aside from straightforward hardware size measurements) that determines the loss to the anode, and the extent of the loss region when the driving source and load are known. The parameter can be calculated in terms of the magnetic field in the region of the null calculated when no electron flow is present. The model is compared to some experimental data, and to simulations of several different hardware geometries, including some cases with multiple nulls, and unbalanced feeds

A Hybrid Single-Carrier/Multicarrier Transmission Scheme with Power Allocation

Directory of Open Access Journals (Sweden)

Luc Féty

2007-11-01

Full Text Available We propose a flexible transmission scheme which easily allows to switch between cyclic-prefixed single-carrier (CP-SC and cyclic-prefixed multicarrier (CP-MC transmissions. This scheme takes advantage of the best characteristic of each scheme, namely, the low peak-to-average power ratio (PAPR of the CP-SC scheme and the robustness to channel selectivity of the CP-MC scheme. Moreover, we derive the optimum power allocation for the CP-SC transmission considering a zero-forcing (ZF and a minimum mean-square error (MMSE receiver. By taking the PAPR into account, we are able to make a better analysis of the overall system and the results show the advantage of the CP-SC-MMSE scheme for flat and mild selective channels due to their low PAPR and that the CP-MC scheme is more advantageous for a narrow range of channels with severe selectivity.

Robust Wireless Power Transmission to mm-Sized Free-Floating Distributed Implants.

Science.gov (United States)

Mirbozorgi, S Abdollah; Yeon, Pyungwoo; Ghovanloo, Maysam

2017-06-01

This paper presents an inductive link for wireless power transmission (WPT) to mm-sized free-floating implants (FFIs) distributed in a large three-dimensional space in the neural tissue that is insensitive to the exact location of the receiver (Rx). The proposed structure utilizes a high-Q resonator on the target wirelessly powered plane that encompasses randomly positioned multiple FFIs, all powered by a large external transmitter (Tx). Based on resonant WPT fundamentals, we have devised a detailed method for optimization of the FFIs and explored design strategies and safety concerns, such as coil segmentation and specific absorption rate limits using realistic finite element simulation models in HFSS including head tissue layers, respectively. We have built several FFI prototypes to conduct accurate measurements and to characterize the performance of the proposed WPT method. Measurement results on 1-mm receivers operating at 60 MHz show power transfer efficiency and power delivered to the load at 2.4% and 1.3 mW, respectively, within 14-18 mm of Tx-Rx separation and 7 cm 2 of brain surface.

ELMO model predicts the price of electric power

International Nuclear Information System (INIS)

Antila, H.

2001-01-01

Electrowatt-Ekono has developed a new model, by which it is possible to make long-term prognoses on the development of electricity prices in the Nordic Countries. The ELMO model can be used as an analysis service of the electricity markets and estimation of the profitability of long-term power distribution contracts with different scenarios. It can also be applied for calculation of technical and economical fundamentals for new power plants, and for estimation of the effects of different taxation models on the emissions of power generation. The model describes the whole power generation system, the power and heat consumption and transmission. The Finnish power generation system is based on the Electrowatt-Ekono's boiler database by combining different data elements. Calculation is based on the assumption that the Nordic power generation system is used optimally, and that the production costs are minimised. In practise the effectively operated electricity markets ensure the optimal use of the production system. The market area to be described consists of Finland and Sweden. The spot prices have long been the same. Norway has been treated as a separate market area. The most potential power generation system, the power consumption and the power transmission system are presumed for the target year during a normal rainfall situation. The basic scenario is calculated on the basis of the preconditional data. The calculation is carried out on hourly basis, which enables the estimation of the price variation of electric power between different times during the day and seasons. The system optimises the power generation on the basis of electricity and heat consumption curves and fuel prices. The result is an hourly limit price for electric power. Estimates are presented as standard form reports. Prices are presented as average annuals, in the seasonal base, and in hourly or daily basis for different seasons

Investigation of hydraulic transmission noise sources

Science.gov (United States)

Klop, Richard J.

Advanced hydrostatic transmissions and hydraulic hybrids show potential in new market segments such as commercial vehicles and passenger cars. Such new applications regard low noise generation as a high priority, thus, demanding new quiet hydrostatic transmission designs. In this thesis, the aim is to investigate noise sources of hydrostatic transmissions to discover strategies for designing compact and quiet solutions. A model has been developed to capture the interaction of a pump and motor working in a hydrostatic transmission and to predict overall noise sources. This model allows a designer to compare noise sources for various configurations and to design compact and inherently quiet solutions. The model describes dynamics of the system by coupling lumped parameter pump and motor models with a one-dimensional unsteady compressible transmission line model. The model has been verified with dynamic pressure measurements in the line over a wide operating range for several system structures. Simulation studies were performed illustrating sensitivities of several design variables and the potential of the model to design transmissions with minimal noise sources. A semi-anechoic chamber has been designed and constructed suitable for sound intensity measurements that can be used to derive sound power. Measurements proved the potential to reduce audible noise by predicting and reducing both noise sources. Sound power measurements were conducted on a series hybrid transmission test bench to validate the model and compare predicted noise sources with sound power.

Using technique vibration diagnostics for assessing the quality of power transmission line supports repairs

Directory of Open Access Journals (Sweden)

Cherpakov Aleksander

2017-01-01

Full Text Available The considered method for assessing the quality of the repair work to restore the rack supports of transmission lines is based on the method of vibration diagnostics. Power transmission line supports with a symmetrical destruction of the protective layer of concrete in the ground in violation of the construction section were chosen as an object. Finite element modelling package Ansys was used in assessing the quality of repair work. The example of evaluating the quality of repair using the relative adhesion defective area design criteria in the analysis of natural vibration frequencies is given.

Energy-Efficient Resource and Power Allocation for Underlay Multicast Device-to-Device Transmission

Directory of Open Access Journals (Sweden)

Fan Jiang

2017-11-01

Full Text Available In this paper, we present an energy-efficient resource allocation and power control scheme for D2D (Device-to-Device multicasting transmission. The objective is to maximize the overall energy-efficiency of D2D multicast clusters through effective resource allocation and power control schemes, while considering the quality of service (QoS requirements of both cellular users (CUs and D2D clusters. We first build the optimization model and a heuristic resource and power allocation algorithm is then proposed to solve the energy-efficiency problem with less computational complexity. Numerical results indicate that the proposed algorithm outperforms existing schemes in terms of throughput per energy consumption.

Environmental concerns regarding electric power transmission in North America

International Nuclear Information System (INIS)

DeCicco, J.M.; Bernow, S.S.; Beyea, J.

1992-01-01

The electric utilities of North America have become ever more interconnected via transmission facilities, largely to insure reliability. Current policy discussions regarding transmission include calls for improved access, increased capacity, and deregulation to facilitate trade in electric power. From an environmental perspective, two issues have been notably absent in much of the debate: (1) a recognition of the full range of environmental impacts related to electricity transmission; and (2) the potential for end-use efficiency to address the reliability and economy requirements that motivate attention to transmission. This paper broaches these issues, starting with an elaboration of the environmental impacts, which range from global and regional effects to local concerns, including the potential health risks associated with electric and magnetic fields. We emphasize that transmission planning should occur as part of an integrated planning process, in which the environmental and social costs of various options are fully considered. We discuss the potential for end-use efficiency to lessen environmental impacts of both transmission and generation. We conclude that there is a need to ensure that environmental externalities and demand-side alternatives are adequately considered when transmission network expansions are proposed. (Author)

Inter-regional transmission and power trading opportunities : making operating agreements work

International Nuclear Information System (INIS)

DesRosiers, D.

2001-01-01

International electric power transmission issues were the focus of this power point presentation which included a corporate profile of the Detroit Edison and International Transmission Company (ITC) and an overview of the midwest U.S. market and the Michigan-Ontario interconnections. ITC owns the transmission assets of its parent company Detroit Edison. It has a commitment with the Federal Energy Regulatory Commission (FERC) to be independent of all market participants within 18 months. ITC's peak load is 11,000 MW with 3 interconnections with Hydro One in Ontario, Consumers Energy in Michigan and First Energy in Ohio. The Ontario-Michigan interface includes four tie lines, 3 near Sarnia and 1 near Windsor, with a total capacity of 1,400 MW into Ontario and 2,000 MW out of Ontario. However, the amount of commercially available power is significantly inhibited by a phenomenon called loopflow, which is the difference between the scheduled and actual power flow. The problems and solutions to loopflow were also outlined. This presentation also briefly discussed the agreement reached between the Alliance RTO and the Midwest ISO that will allow the two to co-exist in the Midwest. tabs., figs

Research on spot power market equilibrium model considering the electric power network characteristics

International Nuclear Information System (INIS)

Wang, Chengmin; Jiang, Chuanwen; Chen, Qiming

2007-01-01

Equilibrium is the optimum operational condition for the power market by economics rule. A realistic spot power market cannot achieve the equilibrium condition due to network losses and congestions. The impact of the network losses and congestion on spot power market is analyzed in this paper in order to establish a new equilibrium model considering the network loss and transmission constraints. The OPF problem formulated according to the new equilibrium model is solved by means of the equal price principle. A case study on the IEEE-30-bus system is provided in order to prove the effectiveness of the proposed approach. (author)

Analyses of the most influential factors for vibration monitoring of planetary power transmissions in pellet mills by adaptive neuro-fuzzy technique

Science.gov (United States)

Milovančević, Miloš; Nikolić, Vlastimir; Anđelković, Boban

2017-01-01

Vibration-based structural health monitoring is widely recognized as an attractive strategy for early damage detection in civil structures. Vibration monitoring and prediction is important for any system since it can save many unpredictable behaviors of the system. If the vibration monitoring is properly managed, that can ensure economic and safe operations. Potentials for further improvement of vibration monitoring lie in the improvement of current control strategies. One of the options is the introduction of model predictive control. Multistep ahead predictive models of vibration are a starting point for creating a successful model predictive strategy. For the purpose of this article, predictive models of are created for vibration monitoring of planetary power transmissions in pellet mills. The models were developed using the novel method based on ANFIS (adaptive neuro fuzzy inference system). The aim of this study is to investigate the potential of ANFIS for selecting the most relevant variables for predictive models of vibration monitoring of pellet mills power transmission. The vibration data are collected by PIC (Programmable Interface Controller) microcontrollers. The goal of the predictive vibration monitoring of planetary power transmissions in pellet mills is to indicate deterioration in the vibration of the power transmissions before the actual failure occurs. The ANFIS process for variable selection was implemented in order to detect the predominant variables affecting the prediction of vibration monitoring. It was also used to select the minimal input subset of variables from the initial set of input variables - current and lagged variables (up to 11 steps) of vibration. The obtained results could be used for simplification of predictive methods so as to avoid multiple input variables. It was preferable to used models with less inputs because of overfitting between training and testing data. While the obtained results are promising, further work is

Transmission Characteristics of an OFDM signal for Power Line Communication System with High Bit Rate

Science.gov (United States)

Mori, Akira; Watanabe, Yosuke; Tokuda, Masamitsu; Kawamoto, Koji

In this paper, we measured what influence the sinusoidal transmission characteristics of the electric power line with various forms gave to the transmission characteristic of OFDM (Orthogonal Frequency Division Multiplexing) signal through PLC (power line communication system) modem. We classified the electric power line transmission line with various forms in a real environment into two basic elements, which are an outlet type branch and a switch type branch. Next, PHY rate (Physical rate) is measured for each basic element connected with the PLC modem. At this time, the transmission characteristics of the electric power line are simulated from measured data. OFDM sending and receiving systems are composed on the computer, and the PHY rate is simulated. By comparing with measured and calculated values, it is revealed that PHY rate of PLC modem is most affected in the case of the power line transmission characteristics having broad band and high level attenuation and group delay variation, and is not affected in the case of that having narrow band attenuation and group delay variation.

A Hearing-Based, Frequency Domain Sound Quality Model for Combined Aerodynamic and Power Transmission Response with Application to Rotorcraft Interior Noise

Science.gov (United States)

Sondkar, Pravin B.

The severity of combined aerodynamics and power transmission response in high-speed, high power density systems such as a rotorcraft is still a major cause of annoyance in spite of recent advancement in passive, semi-active and active control. With further increase in the capacity and power of this class of machinery systems, the acoustic noise levels are expected to increase even more. To achieve further improvements in sound quality, a more refined understanding of the factors and attributes controlling human perception is needed. In the case of rotorcraft systems, the perceived quality of the interior sound field is a major determining factor of passenger comfort. Traditionally, this sound quality factor is determined by measuring the response of a chosen set of juries who are asked to compare their qualitative reactions to two or more sounds based on their subjective impressions. This type of testing is very time-consuming, costly, often inconsistent, and not useful for practical design purposes. Furthermore, there is no known universal model for sound quality. The primary aim of this research is to achieve significant improvements in quantifying the sound quality of combined aerodynamic and power transmission response in high-speed, high power density machinery systems such as a rotorcraft by applying relevant objective measures related to the spectral characteristics of the sound field. Two models have been proposed in this dissertation research. First, a classical multivariate regression analysis model based on currently known sound quality metrics as well some new metrics derived in this study is presented. Even though the analysis resulted in the best possible multivariate model as a measure of the acoustic noise quality, it lacks incorporation of human judgment mechanism. The regression model can change depending on specific application, nature of the sounds and types of juries used in the study. Also, it predicts only the averaged preference scores and

How coupling affects closely packed rectenna arrays used for wireless power transmission

Science.gov (United States)

Walls, Deidra; Choi, Sang H.; Yoon, Hargsoon; Geddis, Demetris; Song, Kyo D.

2017-04-01

The development of power transmission by microwave beam power harvesting attracts manufactures for use of wireless power transmission. Optimizing maximum conversion efficiency is affected by many design parameters, and has been mainly focused previously. Combining several rectennas in one array potentially aides in the amount of microwave energy that can be harvested for energy conversion. Closely packed rectenna arrays is the result of the demand to minimize size and weight for flexibility. This paper specifically focuses on the coupling effects on power; mutual coupling, comparing sparameters and gain total while varying effective parameters. This paper investigates how coupling between each dipole positively and negatively affects the microwave energy, harvesting, and the design limitations.

Some Advances in the Circuit Modeling of Extraordinary Optical Transmission

Directory of Open Access Journals (Sweden)

F. Medina

2009-06-01

Full Text Available The phenomenon of extraordinary optical transmission (EOT through electrically small holes perforated on opaque metal screens has been a hot topic in the optics community for more than one decade. This experimentally observed frequency-selective enhanced transmission of electromagnetic power through holes, for which classical Bethe's theory predicts very poor transmission, later attracted the attention of engineers working on microwave engineering or applied electromagnetics. Extraordinary transmission was first linked to the plasma-like behavior of metals at optical frequencies. However, the primary role played by the periodicity of the distribution of holes was soon made evident, in such a way that extraordinary transmission was disconnected from the particular behavior of metals at optical frequencies. Indeed, the same phenomenon has been observed in the microwave and millimeter wave regime, for instance. Nowadays, the most commonly accepted theory explains EOT in terms of the interaction of the impinging plane wave with the surface plasmon-polariton-Bloch waves (SPP-Bloch supported by the periodically perforated plate. The authors of this paper have recently proposed an alternative model whose details will be briefly summarized here. A parametric study of the predictions of the model and some new potential extensions will be reported to provide additional insight.

Transmission grid security

CERN Document Server

Haarla, Liisa; Hirvonen, Ritva; Labeau, Pierre-Etienne

2011-01-01

In response to the growing importance of power system security and reliability, ""Transmission Grid Security"" proposes a systematic and probabilistic approach for transmission grid security analysis. The analysis presented uses probabilistic safety assessment (PSA) and takes into account the power system dynamics after severe faults. In the method shown in this book the power system states (stable, not stable, system breakdown, etc.) are connected with the substation reliability model. In this way it is possible to: estimate the system-wide consequences of grid faults; identify a chain of eve

MILP Approach for Bilevel Transmission and Reactive Power Planning Considering Wind Curtailment

DEFF Research Database (Denmark)

Ugranli, Faruk; Karatepe, Engin; Nielsen, Arne Hejde

2017-01-01

In this study, two important planning problems in power systems that are transmission expansion and reactive power are formulated as a mixed-integer linear programming taking into account the bilevel structure due to the consideration of market clearing under several load-wind scenarios....... The objective of the proposed method is to minimize the installation cost of transmission lines, reactive power sources, and the annual operation costs of conventional generators corresponding to the curtailed wind energy while maintaining the reliable system operation. Lower level problems of the bilevel...... structure are designated for the market clearing which is formulated by using the linearized optimal power flow equations. In order to obtain mixed-integer linear programming formulation, the so-called lower level problems are represented by using primal-dual formulation. By using the proposed method, power...

Three-phase receiving coil of wireless power transmission system for gastrointestinal robot

Science.gov (United States)

Jia, Z. W.; Jiang, T.; Liu, Y.

2017-11-01

Power shortage is the bottleneck for the wide application of gastrointestinal (GI) robot. Owing to the limited volume and free change of orientation of the receiving set in GI trace, the optimal of receiving set is the key point to promote the transmission efficiency of wireless power transmission system. A new type of receiving set, similar to the winding of three-phase asynchronous motor, is presented and compared with the original three-dimensional orthogonal coil. Considering the given volume and the space utilization ratio, the three-phase and the three-orthogonal ones are the parameters which are optimized and compared. Both the transmission efficiency and stability are analyzed and verified by in vitro experiments. Animal experiments show that the new one could provide at least 420 mW power in volume of Φ11 × 13mm with a uniformity of 78.3% for the GI robot.

A Transmission-Cost-Based Model to Estimate the Amount of Market-Integrable Wind Resources

DEFF Research Database (Denmark)

Morales González, Juan Miguel; Pinson, Pierre; Madsen, Henrik

2012-01-01

are made to share the expenses in transmission derived from their integration, they may see the doors of electricity markets closed for not being competitive enough. This paper presents a model to decide the amount of wind resources that are economically exploitable at a given location from a transmission......In the pursuit of the large-scale integration of wind power production, it is imperative to evaluate plausible frictions among the stochastic nature of wind generation, electricity markets, and the investments in transmission required to accommodate larger amounts of wind. If wind producers......-cost perspective. This model accounts for the uncertain character of wind by using a modeling framework based on stochastic optimization, simulates market barriers by means of a bi-level structure, and considers the financial risk of investments in transmission through the conditional value-at-risk. The major...

1KW Power Transmission Using Wireless Acoustic-Electric Feed-Through (WAEF)

Science.gov (United States)

Sherrit, S.; Bao, X.; Badescu, M.; Aldrich, J.; Bar-Cohen, Y.; Biederman, W.

2008-01-01

A variety of space applications require the delivery of power into sealed structures. Since the structural integrity can be degraded by holes for cabling we present an alternative method of delivering power and information using stress waves to the internal space of a sealed structure. One particular application of this technology is in sample return missions where it is critical to preserve the sample integrity and to prevent earth contamination. Therefore, the container has to be hermetically sealed and the integrity of the seal must be monitored in order to insure to a high degree of reliability the integrity of the sample return vessel. In this study we investigated the use of piezoelectric acoustic-electric power feed-through devices to transfer electric power wirelessly through a solid wall by using elastic or acoustic waves. The technology is applicable to a range of space and terrestrial applications where power is required by electronic equipment inside sealed containers, vacuum or pressure vessels, etc., where holes in the wall are prohibitive or may result in significant structural performance degradation or unnecessarily complex designs. To meet requirements of higher power applications, the feasibility to transfer kilowatts level power was investigated. Pre-stressed longitudinal piezoelectric feed-through devices were analyzed by finite element models and an equivalent circuit model was developed to predict the power transfer characteristics to different electric loads. Based on the results of the analysis a prototype device was designed, fabricated and a demonstration of the transmission of electric power up to 1.068-kW was successfully conducted. Efficiencies in the 80-90% range were also demonstrated and methods to increase the efficiency further are currently being considered.

Capital cost models for geothermal power plants and fluid transmission systems. [GEOCOST

Energy Technology Data Exchange (ETDEWEB)

Schulte, S.C.

1977-09-01

The GEOCOST computer program is a simulation model for evaluating the economics of developing geothermal resources. The model was found to be both an accurate predictor of geothermal power production facility costs and a valid designer of such facilities. GEOCOST first designs a facility using thermodynamic optimization routines and then estimates costs for the selected design using cost models. Costs generated in this manner appear to correspond closely with detailed cost estimates made by industry planning groups. Through the use of this model, geothermal power production costs can be rapidly and accurately estimated for many alternative sites making the evaluation process much simpler yet more meaningful.

Development and Evaluation of cooperative control system for an HVDC transmission system connected with an isolated BWR power plant

International Nuclear Information System (INIS)

Horiuchi, Susumu; Hara, Tsukusi; Matori, Iwao; Hirayama, Kaiichirou.

1987-01-01

In the cooperative control system developed for an HVDC transmission system connected with an isolated BWR power plant, the equilibrium state between power plant output and DC transmission power is examined by way of the detection of the generator frequency. And, thereby start-up and shutdown of the DC system and controlling of the transmission power are made, so that the signal transmission with the power plant becomes unnecessary, enabling the easy cooperative operation. In order to investigate validity of this control system, various digital simulation and simulator test with the control system were carried out. In this way, behavior of the power plant and stability of the DC transmission system were evaluated in the connection to the DC system at power plant start-up, follow of the transmission power in change of the power plant output and in various system failures. (Mori, K.)

A Cognitive Radio-Based Energy-Efficient System for Power Transmission Line Monitoring in Smart Grids

Directory of Open Access Journals (Sweden)

Saeed Ahmed

2017-01-01

Full Text Available The research in industry and academia on smart grids is predominantly focused on the regulation of generated power and management of its consumption. Because transmission of bulk-generated power to the consumer is immensely reliant on secure and efficient transmission grids, comprising huge electrical and mechanical assets spanning a vast geographic area, there is an impending need to focus on the transmission grids as well. Despite the challenges in wireless technologies for SGs, cognitive radio networks are considered promising for provisioning of communications services to SGs. In this paper, first, we present an IEEE 802.22 wireless regional area network cognitive radio-based network model for smart monitoring of transmission lines. Then, for a prolonged lifetime of battery finite monitoring network, we formulate the spectrum resource allocation problem as an energy efficiency maximization problem, which is a nonlinear integer programming problem. To solve this problem in an easier way, we propose an energy-efficient resource-assignment scheme based on the Hungarian method. Performance analysis shows that, compared to a pure opportunistic assignment scheme with a throughput maximization objective and compared to a random scheme, the proposed scheme results in an enhanced lifetime while consuming less battery energy without compromising throughput performance.

Efficiency optimization of wireless power transmission systems for active capsule endoscopes.

Science.gov (United States)

Zhiwei, Jia; Guozheng, Yan; Jiangpingping; Zhiwu, Wang; Hua, Liu

2011-10-01

Multipurpose active capsule endoscopes have drawn considerable attention in recent years, but these devices continue to suffer from energy limitations. A wireless power supply system is regarded as a practical way to overcome the power shortage problem in such devices. This paper focuses on the efficiency optimization of a wireless energy supply system with size and safety constraints. A mathematical programming model in which these constraints are considered is proposed for transmission efficiency, optimal frequency and current, and overall system effectiveness. To verify the feasibility of the proposed method, we use a wireless active capsule endoscope as an illustrative example. The achieved efficiency can be regarded as an index for evaluating the system, and the proposed approach can be used to direct the design of transmitting and receiving coils.

Efficiency optimization of wireless power transmission systems for active capsule endoscopes

International Nuclear Information System (INIS)

Zhiwei, Jia; Guozheng, Yan; Jiangpingping; Zhiwu, Wang; Hua, Liu

2011-01-01

Multipurpose active capsule endoscopes have drawn considerable attention in recent years, but these devices continue to suffer from energy limitations. A wireless power supply system is regarded as a practical way to overcome the power shortage problem in such devices. This paper focuses on the efficiency optimization of a wireless energy supply system with size and safety constraints. A mathematical programming model in which these constraints are considered is proposed for transmission efficiency, optimal frequency and current, and overall system effectiveness. To verify the feasibility of the proposed method, we use a wireless active capsule endoscope as an illustrative example. The achieved efficiency can be regarded as an index for evaluating the system, and the proposed approach can be used to direct the design of transmitting and receiving coils

Modelling and Simulation of VSC-HVDC Connection for Wind Power Plants

DEFF Research Database (Denmark)

Chaudhary, Sanjay Kumar; Teodorescu, Remus; Rodriguez, Pedro

2009-01-01

This paper describes the modelling and simulation of offshore wind power plants (WPP) connected to the onshore power system grid by VSC based HVDC transmission. Offshore wind power plant is modelled with several wind turbine generators connected to two separate collector buses with their own plant...... wind turbines. Simulation of power ramping up and down as well as steady state operation has been demonstrated. As an additional case, the primary reserve control logic has been implemented and simulated in PSCAD model....

Electrical Power Supply to Offshore Oil Installations by High Voltage Direct Current Transmission

Energy Technology Data Exchange (ETDEWEB)

Myhre, Joergen Chr.

2001-07-01

This study was initiated to investigate if it could be feasible to supply offshore oil installations in the North Sea with electrical power from land. A prestudy of alternative converter topologies indicated that the most promising solution would be to investigate a conventional system with reduced synchronous compensator rating. The study starts with a summary of the state of power supply to offshore installations today, and a short review of classical HVDC transmission. It goes on to analyse how a passive network without sources influences the inverter. The transmission, with its current controlled rectifier and large inductance, is simulated as a current source. Under these circumstances the analysis shows that the network frequency has to adapt in order to keep the active and reactive power balance until the controllers are able to react. The concept of firing angle for a thyristor is limited in a system with variable frequency, the actual control parameter is the firing delay time. Sensitivity analysis showed some astonishing consequences. The frequency rises both by an increase in the active and in the reactive load. The voltage falls by an increase in the active load, but rises by an increase in the inductive load. Two different control principles for the system of inverter, synchronous compensator and load are defined. The first takes the reference for the firing delay time from the fundamental voltage at the point of common coupling. The second takes the reference for the firing delay time from the simulated EMF of the synchronous compensator. Of these, the second is the more stable and should be chosen as the basis for a possible control system. Two simulation tools are applied. The first is a quasi-phasor model running on Matlab with Simulink. The other is a time domain model in KREAN. The time domain model is primarily used for the verification of the quasi-phasor model, and shows that quasi-phasors is still a valuable tool for making a quick analysis

Voltage control in the future power transmission systems

DEFF Research Database (Denmark)

Qin, Nan

Wind energy in Denmark covers 42% of the total power consumption in 2015, and will share up to 50% by 2020. Consequently, the conventional power plants are decommissioning. Under the progress of the green transition, the national decision leads to underground many overhead lines in the future...... stages. The voltage uncertainty caused by the wind power forecasting errors is estimated, which is applied as a voltage security margin to further constrain the voltage magnitude in the optimization problem. The problem under the uncertainty is therefore converted to a deterministic problem, which...... to ensure a highly reliable transmission, e.g. balancing the generation and the consumption in large geographic regions, the exchange capacities will be enlarged by upgrading the interconnections. The Danish power system, the electricity transportation hub between the Nordic and continental European systems...

Architecture Analysis of Wireless Power Transmission for Lunar Outposts

Science.gov (United States)

2015-09-01

continuous supply of electrical power would be required. The primary research was to determine if it is feasible to provide power to a lunar polar...space exploration business wish to go beyond the Moon, to Mars and to the asteroids , the technology for these ventures is not yet adequate for the task...klystron, both 16 developed during World War II, that the use of microwaves became available for effective transmission of energy. However, the

Cryogenic System for a High-Temperature Superconducting Power Transmission Cable

International Nuclear Information System (INIS)

Demko, J.A.; Gouge, M.J.; Hughey, R.L.; Lue, J.W.; Martin, R.; Sinha, U.; Stovall, J.P.

1999-01-01

High-temperature superconducting (HTS) cable systems for power transmission are under development that will use pressurized liquid nitrogen to provide cooling of the cable and termination hardware. Southwire Company and Oak Ridge National Laboratory have been operating a prototype HTS cable system that contains many of the typical components needed for a commercial power transmission application. It is being used to conduct research in the development of components and systems for eventual commercial deployment. The cryogenic system was built by Air Products and Chemicals, Allentown, Pennsylvania, and can circulate up to 0.35 kg/s of liquid nitrogen at temperatures as low as 67 K at pressures of 1 to 10 bars. Sufficient cooling is provided for testing a 5-m-long HTS transmission cable system that includes the terminations required for room temperature electrical connections. Testing of the 5-m HTS transmission cable has been conducted at the design ac conditions of 1250 A and 7.5 kV line to ground. This paper contains a description of the essential features of the HTS cable cryogenic system and performance results obtained during operation of the system. The salient features of the operation that are important in large commercial HTS cable applications will be discussed

Switched causual modeling of transmission with clutch in hybrid electric vehicles

OpenAIRE

LHOMME, W; TRIGUI, R; DELARU, P; JEANNERET, B; BOUSCAUROL, A; BADIN, F

2008-01-01

Certain difficulties arise when attempting to model a clutch in a power train transmission due to its nonlinear behavior. Two different states have to be taken into account-the first being when the clutch is locked and the second being when the clutch is slipping. In this paper, a clutch model is developed using the Energetic Macroscopic Representation, which is, in turn, used in the modeling of complete hybrid electric vehicles (HEVs). Two different models are used, and a specific condition ...

An efficient transmission power control scheme for temperature variation in wireless sensor networks.

Science.gov (United States)

Lee, Jungwook; Chung, Kwangsue

2011-01-01

Wireless sensor networks collect data from several nodes dispersed at remote sites. Sensor nodes can be installed in harsh environments such as deserts, cities, and indoors, where the link quality changes considerably over time. Particularly, changes in transmission power may be caused by temperature, humidity, and other factors. In order to compensate for link quality changes, existing schemes detect the link quality changes between nodes and control transmission power through a series of feedback processes, but these approaches can cause heavy overhead with the additional control packets needed. In this paper, the change of the link quality according to temperature is examined through empirical experimentation. A new power control scheme combining both temperature-aware link quality compensation and a closed-loop feedback process to adapt to link quality changes is proposed. We prove that the proposed scheme effectively adapts the transmission power to the changing link quality with less control overhead and energy consumption.

An Efficient Transmission Power Control Scheme for Temperature Variation in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Jungwook Lee

2011-03-01

Full Text Available Wireless sensor networks collect data from several nodes dispersed at remote sites. Sensor nodes can be installed in harsh environments such as deserts, cities, and indoors, where the link quality changes considerably over time. Particularly, changes in transmission power may be caused by temperature, humidity, and other factors. In order to compensate for link quality changes, existing schemes detect the link quality changes between nodes and control transmission power through a series of feedback processes, but these approaches can cause heavy overhead with the additional control packets needed. In this paper, the change of the link quality according to temperature is examined through empirical experimentation. A new power control scheme combining both temperature-aware link quality compensation and a closed-loop feedback process to adapt to link quality changes is proposed. We prove that the proposed scheme effectively adapts the transmission power to the changing link quality with less control overhead and energy consumption.

Structure-property relationships in an Al matrix Ca nanofilamentary composite conductor with potential application in high-voltage power transmission

Science.gov (United States)

Tian, Liang

This study investigated the processing-structure-properties relationships in an Al/Ca composites using both experiments and modeling/simulation. A particular focus of the project was understanding how the strength and electrical conductivity of the composite are related to its microstructure in the hope that a conducting material with light weight, high strength, and high electrical conductivity can be developed to produce overhead high-voltage power transmission cables. The current power transmission cables (e.g., Aluminum Conductor Steel Reinforced (ACSR)) have acceptable performance for high-voltage AC transmission, but are less well suited for high-voltage DC transmission due to the poorly conducting core materials that support the cable weight. This Al/Ca composite was produced by powder metallurgy and severe plastic deformation by extrusion and swaging. The fine Ca metal powders have been produced by centrifugal atomization with rotating liquid oil quench bath, and a detailed study about the atomization process and powder characteristics has been conducted. The microstructure of Al/Ca composite was characterized by electron microscopy. Microstructure changes at elevated temperature were characterized by thermal analysis and indirect resistivity tests. The strength and electrical conductivity were measured by tensile tests and four-point probe resistivity tests. Predicting the strength and electrical conductivity of the composite was done by micro-mechanics-based analytical modeling. Microstructure evolution was studied by mesoscale-thermodynamics-based phase field modeling and a preliminary atomistic molecular dynamics simulation. The application prospects of this composite was studied by an economic analysis. This study suggests that the Al/Ca (20 vol. %) composite shows promise for use as overhead power transmission cables. Further studies are needed to measure the corrosion resistance, fatigue properties and energized field performance of this composite.

Improvement of wireless power transmission efficiency of implantable subcutaneous devices by closed magnetic circuit mechanism.

Science.gov (United States)

Jo, Sung-Eun; Joung, Sanghoon; Suh, Jun-Kyo Francis; Kim, Yong-Jun

2012-09-01

Induction coils were fabricated based on flexible printed circuit board for inductive transcutaneous power transmission. The coil had closed magnetic circuit (CMC) structure consisting of inner and outer magnetic core. The power transmission efficiency of the fabricated device was measured in the air and in vivo condition. It was confirmed that the CMC coil had higher transmission efficiency than typical air-core coil. The power transmission efficiency during a misalignment between primary coil and implanted secondary coil was also evaluated. The decrease of mutual inductance between the two coils caused by the misalignment led to a low efficiency of the inductive link. Therefore, it is important to properly align the primary coil and implanted secondary coil for effective power transmission. To align the coils, a feedback coil was proposed. This was integrated on the backside of the primary coil and enabled the detection of a misalignment of the primary and secondary coils. As a result of using the feedback coil, the primary and secondary coils could be aligned without knowledge of the position of the implanted secondary coil.

A control-oriented simulation model of a power-split hybrid electric vehicle

International Nuclear Information System (INIS)

Cipek, Mihael; Pavković, Danijel; Petrić, Joško

2013-01-01

Highlights: ► A simulation model of a two mode power-split hybrid electric vehicle (HEV) is proposed. ► Modeling the energy losses in the HEV transmission components are presented. ► The control optimization model implementation aspects are discussed. -- Abstract: A simulation model of a two mode power-split hybrid electric vehicle (HEV) is proposed in this paper for the purpose of HEV dynamics analysis and control system design. The bond graph methodology is used to model dominant dynamic effects of the mechanical part of the HEV transmission. Simple quasi-static battery model, the environment model, the tire and the power losses model of a vehicle are included, as well. A low-level electric generator speed control loop is designed, which includes a PI controller tuned according to the symmetrical optimum tuning procedure. Finally, off-line optimization by conjugate gradient-based BPTT-like optimal control algorithm, which is based on the presented mathematical model, is also given in the paper.

Transmission Reinforcements in the Central American Regional Power System

Energy Technology Data Exchange (ETDEWEB)

Elizondo, Marcelo A.; Vallem, Mallikarjuna R.; Samaan, Nader A.; Makarov, Yuri V.; Vyakaranam, Bharat; Nguyen, Tony B.; Munoz, Christian; Herrera, Ricardo; Midence, Diego; Shpitsberg, Anna

2016-07-25

The Central American regional interconnected power system (SER) connects the countries members of the Central American regional electricity market (MER): Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, and Panama. The SER was a result of a long term regional effort, and was initially conceived to transfer 300 MW between countries. However, the current transfer limits between countries range from 70 MW to 300 MW. Regional entities, like CRIE (Regional Commission of Electrical Interconnection), EOR (Central American Regional System Operator), and CDMER (Board of Directors of the Central American Market) are working on coordinating the national transmission expansion plans with regional transmission planning efforts. This paper presents experience in Central America region to recommend transmission reinforcements to achieve 300 MW transfer capacity between any pair of member countries of the Central American regional electricity market (MER). This paper also provides a methodology for technical analysis and for coordination among the regional and national entities. This methodology is unique for transmission systems of these characteristics.

Incorporating energy efficiency into electric power transmission planning: A western United States case study

International Nuclear Information System (INIS)

Barbose, Galen L.; Sanstad, Alan H.; Goldman, Charles A.

2014-01-01

Driven by system reliability goals and the need to integrate significantly increased renewable power generation, long-range, bulk-power transmission planning processes in the United States are undergoing major changes. At the same time, energy efficiency is an increasing share of the electricity resource mix in many regions, and has become a centerpiece of many utility resource plans and state policies as a means of meeting electricity demand, complementing supply-side sources, and reducing carbon dioxide emissions from the electric power system. The paper describes an innovative project in the western United States to explicitly incorporate end-use efficiency into load forecasts – projections of electricity consumption and demand – that are a critical input into transmission planning and transmission planning studies. Institutional and regulatory background and context are reviewed, along with a detailed discussion of data sources and analytical procedures used to integrate efficiency into load forecasts. The analysis is intended as a practical example to illustrate the kinds of technical and institutional issues that must be addressed in order to incorporate energy efficiency into regional transmission planning activities. - Highlights: • Incorporating energy efficiency into electric power transmission planning is an emergent analytical and policy priority. • A new methodology for this purpose was developed and applied in the western U.S. transmission system. • Efficiency scenarios were created and incorporated into multiple load forecasts. • Aggressive deployment of efficiency policies and programs can significantly reduce projected load. • The approach is broadly applicable in long-range transmission planning

Wireless power transmission to an electromechanical receiver using low-frequency magnetic fields

International Nuclear Information System (INIS)

Challa, Vinod R; Arnold, David P; Mur-Miranda, Jose Oscar

2012-01-01

A near-field, electrodynamically coupled wireless power transmission system is presented that delivers electrical power from a transmitter coil to a compact electromechanical receiver. The system integrates electromechanical energy conversion and mechanical resonance to deliver power over a range of distances using low-amplitude, low-frequency magnetic fields. Two different receiver orientations are investigated that rely on either the force or the torque induced on the receiver magnet at separation distances ranging from 2.2 to 10.2 cm. Theoretical models for each mode compare the predicted performance with the experimental results. For a 7.1 mA pk sinusoidal current supplied to a transmitter coil with a 100 cm diameter, the torque mode receiver orientation has a maximum power transfer of 150 μW (efficiency of 12%) at 2.2 cm at its resonance frequency of 38.4 Hz. For the same input current to the transmitter, the force mode receiver orientation has a maximum power transfer of 37 μW (efficiency of 4.1%) at 3.1 cm at its resonance frequency of 38.9 Hz. (paper)

Power transmission study for a wave energy scheme based on Lancaster Flexible Bag devices. Supervisory and telecontrol system

Energy Technology Data Exchange (ETDEWEB)

1981-11-01

Various options are considered for power data transmission associated with the power collection and transmission system of a postulated wave energy conversion scheme off the Outer Hebrides. For data transmission between the off-shore and on-shore power collector stations a Power Line Carrier (PLC) system is judged to be most suitable. In the case of data transmission between power collector stations and the main control centre, a microwave/radio link is proposed as the amount of data does not lend itself to a PLC system. Cost estimates, in the main for equipment supply only, are given.

Engineering science research issues in high power density transmission dynamics for aerospace applications. [rotorcraft geared rotors

Science.gov (United States)

Singh, Rajendra; Houser, Donald R.

1993-01-01

This paper discusses analytical and experimental approaches that will be needed to understand dynamic, vibro-acoustic and design characteristics of high power density rotorcraft transmissions. Complexities associated with mathematical modeling of such systems will be discussed. An overview of research work planned during the next several years will be presented, with emphasis on engineering science issues such as gear contact mechanics, multi-mesh drive dynamics, parameter uncertainties, vibration transmission through bearings, and vibro-acoustic characteristics of geared rotor systems and housing-mount structures. A few examples of work in progress are cited.

[An implantable micro-device using wireless power transmission for measuring aortic aneurysm sac pressure].

Science.gov (United States)

Guo, Xudong; Ge, Bin; Wang, Wenxing

2013-08-01

In order to detect endoleaks after endovascular aneurysm repair (EVAR), we developed an implantable micro-device based on wireless power transmission to measure aortic aneurysm sac pressure. The implantable micro-device is composed of a miniature wireless pressure sensor, an energy transmitting coil, a data recorder and a data processing platform. Power transmission without interconnecting wires is performed by a transmitting coil and a receiving coil. The coupling efficiency of wireless power transmission depends on the coupling coefficient between the transmitting coil and the receiving coil. With theoretical analysis and experimental study, we optimized the geometry of the receiving coil to increase the coupling coefficient. In order to keep efficiency balance and satisfy the maximizing conditions, we designed a closed loop power transmission circuit, including a receiving voltage feedback module based on wireless communication. The closed loop improved the stability and reliability of transmission energy. The prototype of the micro-device has been developed and the experiment has been performed. The experiments showed that the micro-device was feasible and valid. For normal operation, the distance between the transmitting coil and the receiving coil is smaller than 8cm. Besides, the distance between the micro-device and the data recorder is within 50cm.

Evaluating the capacity value of wind power considering transmission and operational constraints

International Nuclear Information System (INIS)

Gil, Esteban; Aravena, Ignacio

2014-01-01

Highlights: • Discussion of power system adequacy and the capacity value of wind power. • Method for estimating capacity value of wind power is proposed. • Monte Carlo simulation used to consider transmission and operational constraints. • Application of the method to the Chilean Northern Interconnected System (SING). - Abstract: This paper presents a method for estimating the capacity value of wind considering transmission and operational constraints. The method starts by calculating a metric for system adequacy by repeatedly simulating market operations in a Monte Carlo scheme that accounts for forced generator outages, wind resource variability, and operational conditions. Then, a capacity value calculation that uses the simulation results is proposed, and its application to the Chilean Northern Interconnected System (SING) is discussed. A comparison of the capacity value for two different types of wind farms is performed using the proposed method, and the results are compared with the method currently used in Chile and the method recommended by the IEEE. The method proposed in the paper captures the contribution of the variable generation resources to power system adequacy more accurately than the method currently employed in the SING, and showed capable of taking into account transmission and operational constraints

Transient analysis for alternating over-current characteristics of HTSC power transmission cable

Science.gov (United States)

Lim, S. H.; Hwang, S. D.

2006-10-01

In this paper, the transient analysis for the alternating over-current distribution in case that the over-current was applied for a high-TC superconducting (HTSC) power transmission cable was performed. The transient analysis for the alternating over-current characteristics of HTSC power transmission cable with multi-layer is required to estimate the redistribution of the over-current between its conducting layers and to protect the cable system from the over-current in case that the quench in one or two layers of the HTSC power cable happens. For its transient analysis, the resistance generation of the conducting layers for the alternating over-current was reflected on its equivalent circuit, based on the resistance equation obtained by applying discrete Fourier transform (DFT) for the voltage and the current waveforms of the HTSC tape, which comprises each layer of the HTSC power transmission cable. It was confirmed through the numerical analysis on its equivalent circuit that after the current redistribution from the outermost layer into the inner layers first happened, the fast current redistribution between the inner layers developed as the amplitude of the alternating over-current increased.

Experimental study on an S-band near-field microwave magnetron power transmission system on hundred-watt level

Science.gov (United States)

Zhang, Biao; Jiang, Wan; Yang, Yang; Yu, Chengyang; Huang, Kama; Liu, Changjun

2015-11-01

A multi-magnetron microwave source, a metamaterial transmitting antenna, and a large power rectenna array are presented to build a near-field 2.45 GHz microwave power transmission system. The square 1 m2 rectenna array consists of sixteen rectennas with 2048 Schottky diodes for large power microwave rectifying. It receives microwave power and converts them into DC power. The design, structure, and measured performance of a unit rectenna as well as the entail rectenna array are presented in detail. The multi-magnetron microwave power source switches between half and full output power levels, i.e. the half-wave and full-wave modes. The transmission antenna is formed by a double-layer metallic hole array, which is applied to combine the output power of each magnetron. The rectenna array DC output power reaches 67.3 W on a 1.2 Ω DC load at a distance of 5.5 m from the transmission antenna. DC output power is affected by the distance, DC load, and the mode of microwave power source. It shows that conventional low power Schottky diodes can be applied to a microwave power transmission system with simple magnetrons to realise large power microwave rectifying.

Power electronic converters modeling and control with case studies

CERN Document Server

Bacha, Seddik; Bratcu, Antoneta Iuliana

2014-01-01

Modern power electronic converters are involved in a very broad spectrum of applications: switched-mode power supplies, electrical-machine-motion-control, active power filters, distributed power generation, flexible AC transmission systems, renewable energy conversion systems and vehicular technology, among them. Power Electronics Converters Modeling and Control teaches the reader how to analyze and model the behavior of converters and so to improve their design and control. Dealing with a set of confirmed algorithms specifically developed for use with power converters, this text is in two parts: models and control methods. The first is a detailed exposition of the most usual power converter models: ·        switched and averaged models; ·        small/large-signal models; and ·        time/frequency models. The second focuses on three groups of control methods: ·        linear control approaches normally associated with power converters; ·        resonant controllers b...

Curing critical links in oscillator networks as power flow models

International Nuclear Information System (INIS)

Rohden, Martin; Meyer-Ortmanns, Hildegard; Witthaut, Dirk; Timme, Marc

2017-01-01

Modern societies crucially depend on the robust supply with electric energy so that blackouts of power grids can have far reaching consequences. Typically, large scale blackouts take place after a cascade of failures: the failure of a single infrastructure component, such as a critical transmission line, results in several subsequent failures that spread across large parts of the network. Improving the robustness of a network to prevent such secondary failures is thus key for assuring a reliable power supply. In this article we analyze the nonlocal rerouting of power flows after transmission line failures for a simplified AC power grid model and compare different strategies to improve network robustness. We identify critical links in the grid and compute alternative pathways to quantify the grid’s redundant capacity and to find bottlenecks along the pathways. Different strategies are developed and tested to increase transmission capacities to restore stability with respect to transmission line failures. We show that local and nonlocal strategies typically perform alike: one can equally well cure critical links by providing backup capacities locally or by extending the capacities of bottleneck links at remote locations. (paper)

Choice of antenna geometry for microwave power transmission from solar power satellites

Science.gov (United States)

Potter, Seth D.

1992-01-01

A comparison is made between square and circular transmitting antennas for solar power satellite microwave power transmission. It is seen that the exclusion zone around the rectenna needed to protect populations from microwaves is smaller for a circular antenna operating at 2.45 GHz than it is for a square antenna at that frequency. If the frequency is increased, the exclusion zone size remains the same for a square antenna, but becomes even smaller for a circular antenna. Peak beam intensity is the same for both antennas if the frequency and antenna area are equal. The circular antenna puts a somewhat greater amount of power in the main lobe and somewhat less in the side lobes. Since rain attenuation and atmospheric heating remain problems above 10 GHz, it is recommended that future solar power satellite work concentrate on circular transmitting antennas at frequencies of roughly 10 GHz.

Batteryless wireless transmission system for electronic drum uses piezoelectric generator for play signal and power source

International Nuclear Information System (INIS)

Nishikawa, H; Yoshimi, A; Takemura, K; Tanaka, A; Douseki, T

2015-01-01

A batteryless self-powered wireless transmission system has been developed that sends a signal from a drum pad to a synthesizer. The power generated by a piezoelectric generator functions both as the “Play” signal for the synthesizer and as the power source for the transmitter. An FM transmitter, which theoretically operates with zero latency, and a receiver with quick-response squelch of the received signal were developed for wireless transmission with a minimum system delay. Experimental results for an electronic drum without any connecting wires fully demonstrated the feasibility of self-powered wireless transmission with a latency of 900 μs. (paper)

Space Solar Power Technology Demonstration for Lunar Polar Applications: Laser-Photovoltaic Wireless Power Transmission

Science.gov (United States)

Henley, M. W.; Fikes, J. C.; Howell, J.; Mankins, J. C.; Howell, Joe T. (Technical Monitor)

2002-01-01

Space Solar Power technology offers unique benefits for near-term NASA space science missions, which can mature this technology for other future applications. "Laser-Photo-Voltaic Wireless Power Transmission" (Laser-PV WPT) is a technology that uses a laser to beam power to a photovoltaic receiver, which converts the laser's light into electricity. Future Laser-PV WPT systems may beam power from Earth to satellites or large Space Solar Power satellites may beam power to Earth, perhaps supplementing terrestrial solar photo-voltaic receivers. In a near-term scientific mission to the moon, Laser-PV WPT can enable robotic operations in permanently shadowed lunar polar craters, which may contain ice. Ground-based technology demonstrations are proceeding, to mature the technology for this initial application, in the moon's polar regions.

Regional transmission subsystem planning

Energy Technology Data Exchange (ETDEWEB)

Costa Bortoni, Edson da [Quadrante Softwares Especializados Ltda., Itajuba, MG (Brazil); Bajay, Sergio Valdir; Barros Correia, Paulo de [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica; Santos, Afonso Henriques Moreira; Haddad, Jamil [Escola Federal de Engenharia de Itajuba, MG (Brazil)

1994-12-31

This work presents an approach for the planning of transmission systems by employing mixed--integer linear programming to obtain a cost and operating characteristics optimized system. The voltage loop equations are written in a modified form, so that, at the end of the analysis, the model behaves as a DC power flow, with the help of the two Kirchhoff`s laws, exempting the need of interaction with an external power flow program for analysis of the line loading. The model considers the occurrence of contingencies, so that the final result is a network robust to the most severe contingencies. This whole technique is adapted to the regional electric power transmission subsystems. (author) 9 refs., 4 figs.

Location matters: The impact of renewable power on transmission congestion and emissions

International Nuclear Information System (INIS)

Hitaj, Claudia

2015-01-01

Many governments offer subsidies for renewable power to reduce greenhouse gas emissions in the power sector. However, most support schemes for renewable power do not take into account that emissions depend on the location of renewable and conventional power plants within an electricity grid. I simulate optimal power flow in a test grid when 4 renewable power plants connect to the grid across 24 potential sites, amounting to over 10,000 configurations. Each configuration is associated with different levels of emissions and renewable power output. I find that emission reductions vary by a factor of 7 and that curtailment due to transmission congestion is more likely when renewable power plants are concentrated in an area of the grid with low demand. Large cost savings could be obtained by allowing subsidies for renewable power to vary across locations according to abatement potential or by replacing subsidies with a price on emissions. - Highlights: • Analyze the impact of renewable power plant location on congestion and emissions. • Simulate optimal power flow in a test grid for over 10,000 configurations. • Determine that emission reductions vary by a factor of 7. • Find that renewable power is curtailed due to transmission congestion. • Pricing emissions is most efficient since abatement potential varies across locations.

Transmission of power at high voltages

Energy Technology Data Exchange (ETDEWEB)

Lane, F J

1963-01-01

High voltage transmission is considered to be concerned with circuits and systems operating at or above 132 kV. While the general examination is concerned with ac transmission, dc systems are also included. The choice of voltage for a system will usually involve hazardous assessments of the future requirements of industry, commerce and a changing population. Experience suggests that, if the estimated economic difference between two voltages is not significant, there is good reason to choose the higher voltage, as this will make the better provision for unexpected future expansion. Two principal functions served by transmission circuits in a supply system are: (a) the transportation of energy in bulk from the generator to the reception point in the distribution system; and (b) the interconnection and integration of the generating plant and associated loads. These functions are considered and various types of system are discussed in terms of practicability, viability, quality and continuity of supply. Future developments requiring transmission voltages up to 750 kV will raise many problems which are in the main empirical. Examples are given of the type of problem envisaged and it is suggested that these can only be partially solved by theory and model operation.

A GIS-based Power Transmission Management Information System

Institute of Scientific and Technical Information of China (English)

2010-01-01

<正>Based on analyzing the shortcomings of electric power enterprise in traditional operation pattern,this paper combines components GIS with the application of management information system,and uses the structure which unifies three layers C/S and B/S.Also,proposed using the GPS intellectualization patrol.This may be useful to guarantees the transmission line’s operation to be safe and stable.

Sensor Transmission Power Schedule for Smart Grids

Science.gov (United States)

Gao, C.; Huang, Y. H.; Li, J.; Liu, X. D.

2017-11-01

Smart grid has attracted much attention by the requirement of new generation renewable energy. Nowadays, the real-time state estimation, with the help of phasor measurement unit, plays an important role to keep smart grid stable and efficient. However, the limitation of the communication channel is not considered by related work. Considering the familiar limited on-board batteries wireless sensor in smart grid, transmission power schedule is designed in this paper, which minimizes energy consumption with proper EKF filtering performance requirement constrain. Based on the event-triggered estimation theory, the filtering algorithm is also provided to utilize the information contained in the power schedule. Finally, its feasibility and performance is demonstrated using the standard IEEE 39-bus system with phasor measurement units (PMUs).

Transmission congestion management in the electricity market

Science.gov (United States)

Chen, Yue

2018-04-01

In this paper we mainly discuss how to optimize the arrangement to decrease the loss of each line when the power generation side of the system transmission congestion occurs in a safe and economical manner. We respectively set the adjust model if the transmission can be eliminated which can calculate the best scheme and safety margin model when transmission cannot be eliminated which is a multi-objective planning problem. We solve the two models on the condition of the load power demands are 982.4MW and 1052.8 MW by Lingo and get the optimal management scheme.

In-Containment Signal Acquisition and Data Transmission via Power Lines within High Dose Areas of Nuclear Power Plants

International Nuclear Information System (INIS)

Mueller Steffen; Wibbing Sascha; Weigel Robert; Koelpin Alexander; Dennerlein, Juergen; Janke, Iryna; Weber, Johannes

2015-01-01

Signal acquisition and data transmission for innovative sensor systems and networks inside the containment of nuclear power plants (NPPs) is still a challenge with respect to safety, performance, reliability, availability, and costs. This especially applies to equipment upgrades for existing plants, special measurements, but also for new builds. This paper presents a novel method for efficient and cost-effective sensor signal acquisition and data transmission via power lines, in order to cope with the disadvantages of common system architectures that often suffer from poor signal integrity due to raw data transmissions via long cables, huge efforts and costs for installation, and low flexibility with respect to maintenance and upgrades. A transmitter-receiver architecture is proposed that allows multiplexing of multiple sensor inputs for unidirectional point-to-point transmission by superimposing information signals on existing AC or DC supply lines, but also on active and inactive sensor wires, or spare cables, using power line communication (PLC) technology. Based on commercial off-the-shelf (COTS) electronic parts, a radiation hard transmitter hardware is designed to operate in harsh environment within the containment during full plant operation. The system's modular approach allows application specific trade-offs between redundancy and throughput regarding data transmission, as well as various sensor input front-ends which are compatible with state of the art systems. PLC technology eliminates the need for costly installation of additional cables and wall penetrations, while providing a complementary and diverse communication technology for upgrades of existing systems. At the receiver side in low dose areas, signals are extracted from the power line, demodulated, and de-multiplexed, in order to regain the original sensor signal information and provide it either in analog or digital output format. Successful laboratory qualification tests, field trails

In-Containment Signal Acquisition and Data Transmission via Power Lines within High Dose Areas of Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Mueller Steffen; Wibbing Sascha; Weigel Robert; Koelpin Alexander [Institute for Electronics Engineering, University of Erlangen-Nuremberg (Germany); Dennerlein, Juergen; Janke, Iryna; Weber, Johannes [AREVA GmbH, Paul-Gossen-Str. 100, 91052 Erlangen (Germany)

2015-07-01

Signal acquisition and data transmission for innovative sensor systems and networks inside the containment of nuclear power plants (NPPs) is still a challenge with respect to safety, performance, reliability, availability, and costs. This especially applies to equipment upgrades for existing plants, special measurements, but also for new builds. This paper presents a novel method for efficient and cost-effective sensor signal acquisition and data transmission via power lines, in order to cope with the disadvantages of common system architectures that often suffer from poor signal integrity due to raw data transmissions via long cables, huge efforts and costs for installation, and low flexibility with respect to maintenance and upgrades. A transmitter-receiver architecture is proposed that allows multiplexing of multiple sensor inputs for unidirectional point-to-point transmission by superimposing information signals on existing AC or DC supply lines, but also on active and inactive sensor wires, or spare cables, using power line communication (PLC) technology. Based on commercial off-the-shelf (COTS) electronic parts, a radiation hard transmitter hardware is designed to operate in harsh environment within the containment during full plant operation. The system's modular approach allows application specific trade-offs between redundancy and throughput regarding data transmission, as well as various sensor input front-ends which are compatible with state of the art systems. PLC technology eliminates the need for costly installation of additional cables and wall penetrations, while providing a complementary and diverse communication technology for upgrades of existing systems. At the receiver side in low dose areas, signals are extracted from the power line, demodulated, and de-multiplexed, in order to regain the original sensor signal information and provide it either in analog or digital output format. Successful laboratory qualification tests, field trails

Issues affecting the electricity transmission system in Mexico under a competitive integrated model

Energy Technology Data Exchange (ETDEWEB)

Avila Rosales, M.A.; Gonzalez Flores, J. [Federal Electricity Commission, Mexico City (Mexico)

2008-07-01

The electricity sector in Mexico is undergoing a process of significant structural change. The traditional industry framework has been exposed to new market structures and greater competition, both of which are being introduced by changing regulations regarding who can generate, transmit, distribute and sell electricity. Mexico's power industry is changing to a competitive integrated model. Electricity industry restructuring is partly based on the assumption that transmission systems should be flexible, reliable, and open to all exchanges no matter where the suppliers and consumers of energy are located and who they are. However, neither the existing transmission systems nor its management infrastructure can fully support this open exchange. This paper described the primary issues affecting the transmission system in Mexico under a competitive environment and a transmission expansion planning approach that took the uncertainties associated with the location and size of new generating power stations into consideration in order to produce least-cost and robust transmission plans. The paper described the planning process, including a rigorous analysis of the economics of the resulting transmission plans. Specifically, the paper described the current regulatory framework and supply adequacy as well as current procedures and methodologies for transmission management and expansion planning. The transmission planning methodology was also presented. This included a minimum cost analysis; profit analysis; and least-cost transmission plan. It was concluded that the transmission expansion planning approach stressed that a horizon year viewpoint was important because transmission additions have long-term use. The transmission expansion planning approach, further defined the process of selecting transmission projects as one of comparing and optimizing attributes such as near-term needs; long-term utilization; contribution to overall reliability; and favorable or least

The Effect of Friction on the Nonlinear Vibration of the Cracked One-Stage Power Transmission

Directory of Open Access Journals (Sweden)

M. Rezaee

2016-01-01

Full Text Available : The gear systems are widely used in industry to transmit the power or change the direction of the torque. Due to the extensive usage of the gears, the detailed designing and the subsequent maintenance of these systems are more and more evident. System recognition can be achieved through modeling the system, investigating the system behavior, and comparing the results obtained through the model with the actual system behavior. Up to now, the effect of dry friction has not been taken into account in nonlinear vibration analysis and modeling of a cracked one-stage gear power transmission system. In this paper, the nonlinear vibration of a pair of cracked spur-gear system in presence of dry friction, static transmission error, clearance and time-variant mesh stiffness is investigated. To this end, the time-variant mesh stiffness of an intact tooth is calculated analytically. Then, the tooth root crack is modeled as a cracked cantilever beam. The governing nonlinear equation of motion is extracted accordingly, and in order to consider the effect of dry friction, the governing equation solved by Rung- Kutta method in three separate time spans. Finally, the frequency response and bifurcation diagrams are used to study the effect of the friction and tooth root crack on the nonlinear vibration behavior of the system.

A mid-term, market-based power systems planning model

International Nuclear Information System (INIS)

Koltsaklis, Nikolaos E.; Dagoumas, Athanasios S.; Georgiadis, Michael C.; Papaioannou, George; Dikaiakos, Christos

2016-01-01

Highlights: • A mid-term Energy Planning along with a Unit Commitment model is developed. • The model identifies the optimum interconnection capacity. • Electricity interconnections affect the power mix and the day-ahead spot price. • Renewables’ penetration has impacts on the power reserves and the CO_2 emissions. • Energy policy and fuel pricing can have significant impacts on the power mix. - Abstract: This paper presents a generic Mixed Integer Linear Programming (MILP) model that integrates a Mid-term Energy Planning (MEP) model, which implements generation and transmission system planning at a yearly level, with a Unit Commitment (UC) model, which performs the simulation of the Day-Ahead Electricity Market. The applicability of the proposed model is illustrated in a case study of the Greek interconnected power system. The aim is to evaluate a critical project in the Ten Year Network Development Plan (TYNDP) of the Independent Power Transmission System Operator S.A. (ADMIE), namely the electric interconnection of the Crete Island with the mainland electric system. The proposed modeling framework identifies the implementation (or not) of the interconnection of the Crete Island with the mainland electric system, as well as the optimum interconnection capacity. It also quantifies the effects on the Day-Ahead electricity market and on the energy mix. The paper demonstrates that the model can provide useful insights into the strategic and challenging decisions to be determined by investors and/or policy makers at a national and/or regional level, by providing the optimal energy roadmap and management, as well as clear price signals on critical energy projects under real operating and design constraints.

An applicable 5.8 GHz wireless power transmission system with rough beamforming to Project Loon

Directory of Open Access Journals (Sweden)

Chang-Jun Ahn

2016-06-01

Full Text Available In recent, Google proposed the Project Loon being developed with the mission of providing internet access to rural and remote areas using high-altitude balloons. In this paper, we describe an applicable prototype of 5.8 GHz wireless power transmission system with rough beamforming method to Project Loon. From the measurement results, transmit beamforming phased array antenna can transmit power more efficiently compared to a horn antenna and array antenna without beamforming with increasing the transmission distance. For the transmission distance of 1000 mm, transmit beamforming phased array antenna can obtain higher received power about 1.46 times compared to array antenna without transmit beamforming.

Autonomous transmission power adaptation for multi-radio multi-channel wireless mesh networks

CSIR Research Space (South Africa)

Olwal, TO

2009-09-01

Full Text Available Multi-Radio Multi-Channel (MRMC) systems are key to power control problems in WMNs. Previous studies have emphasized through- put maximization in such systems as the main design challenge and transmission power control treated as a secondary issue...

Autonomous transmission power adaptation for multi-radio multi-channel wireless mesh networks

CSIR Research Space (South Africa)

Olwal, TO

2008-09-01

Full Text Available Multi-Radio Multi-Channel (MRMC) systems are key to power control problems in WMNs. Previous studies have emphasized throughput maximization in such systems as the main design challenge and transmission power control treated as a secondary issue...

An RFID-Based Closed-Loop Wireless Power Transmission System for Biomedical Applications.

Science.gov (United States)

Kiani, Mehdi; Ghovanloo, Maysam

2010-04-01

This brief presents a standalone closed-loop wireless power transmission system that is built around a commercial off-the-shelf (COTS) radio-frequency identification (RFID) reader (TRF7960) operating at 13.56 MHz. It can be used for inductively powering implantable biomedical devices in a closed loop. Any changes in the distance and misalignment between transmitter and receiver coils in near-field wireless power transmission can cause a significant change in the received power, which can cause either a malfunction or excessive heat dissipation. RFID circuits are often used in an open loop. However, their back telemetry capability can be utilized to stabilize the received voltage on the implant. Our measurements showed that the delivered power to the transponder was maintained at 11.2 mW over a range of 0.5 to 2 cm, while the transmitter power consumption changed from 78 mW to 1.1 W. The closed-loop system can also oppose voltage variations as a result of sudden changes in the load current.

Proximity effects of high voltage electric power transmission lines on ...

African Journals Online (AJOL)

Yomi

2010-08-18

Aug 18, 2010 ... transmission lines on ornamental plant growth. Zeki Demir ... The effects of proximity to power-line on specific leaf area and seedling dbh were tested .... during vegetation season is about 72% and common wind blow.

Marine High Voltage Power Conditioning and Transmission System with Integrated Storage DE-EE0003640 Final Report

Energy Technology Data Exchange (ETDEWEB)

Frank Hoffmann, PhD; Aspinall, Rik

2012-12-10

Design, Development, and test of the three-port power converter for marine hydrokinetic power transmission. Converter provides ports for AC/DC conversion of hydrokinetic power, battery storage, and a low voltage to high voltage DC port for HVDC transmission to shore. The report covers the design, development, implementation, and testing of a prototype built by PPS.

Dispatchable Renewable Energy Model for Microgrid Power System

Energy Technology Data Exchange (ETDEWEB)

Chiou, Fred; Gentle, Jake P.; McJunkin, Timothy R.

2017-04-01

Over the years, many research projects have been performed and focused on finding out the effective ways to balance the power demands and supply on the utility grid. The causes of the imbalance could be the increasing demands from the end users, the loss of power generation (generators down), faults on the transmission lines, power tripped due to overload, and weather conditions, etc. An efficient Load Frequency Control (LFC) can assure the desired electricity quality provided to the residential, commercial and industrial end users. A simulation model is built in this project to investigate the contribution of the modeling of dispatchable energy such as solar energy, wind power, hydro power and energy storage to the balance of the microgrid power system. An analysis of simplified feedback control system with proportional, integral, and derivative (PID) controller was performed. The purpose of this research is to investigate a simulation model that achieves certain degree of the resilient control for the microgrid.

Modeling and application of VSC-HVDC in the European transmission system

International Nuclear Information System (INIS)

L'Abatte, A.; Fulli, G.

2010-01-01

This paper investigated the potential technical, environmental, and economic impacts of voltage source converter (VSC) based high voltage direct current (HVDC) technologies on the European power system, with particular emphasis on enhancing the attainable transmission capacity in specific applications. To this end, an original steady-state model of the VSC-HVDC was presented and tested. A techno-economic analysis of the potential impact of VSC-HVDC on liberalized power systems in Europe was performed to determine the feasibility of such investment compared to building conventional high voltage alternating current (HVAC) transmission infrastructures. The land use and environmental impact of HVDC may be lower than HVAC technologies. VSC-HVDC offers several advantages over conventional HVDC, including flexibility and range of power control, compactness and modularity of converter stations, easier expandability for multi-terminal configurations, and greater environmental friendliness. The relative disadvantages of the VSC-HVDC include a greater expense and higher converter losses. When replacing existing HVAC lines, some targeted VSC-HVDC installations were shown to be technologically and economically feasible, particularly when installed on lines between regions with a high electricity price differential, although less profitable than building new HVAC lines. VSC-HVDC can be a more feasible option when socio-political and environmental restraints curtail the extension of the HVAC transmission system. 29 refs., 6 tabs., 4 figs.

Subwavelength elastic joints connecting torsional waveguides to maximize the power transmission coefficient

Science.gov (United States)

Lee, Joong Seok; Lee, Il Kyu; Seung, Hong Min; Lee, Jun Kyu; Kim, Yoon Young

2017-03-01

Joints with slowly varying tapered shapes, such as linear or exponential profiles, are known to transmit incident wave power efficiently between two waveguides with dissimilar impedances. This statement is valid only when the considered joint length is longer than the wavelengths of the incident waves. When the joint length is shorter than the wavelengths, however, appropriate shapes of such subwavelength joints for efficient power transmission have not been explored much. In this work, considering one-dimensional torsional wave motion in a cylindrical elastic waveguide system, optimal shapes or radial profiles of a subwavelength joint maximizing the power transmission coefficient are designed by a gradient-based optimization formulation. The joint is divided into a number of thin disk elements using the transfer matrix approach and optimal radii of the disks are determined by iterative shape optimization processes for several single or bands of wavenumbers. Due to the subwavelength constraint, the optimized joint profiles were found to be considerably different from the slowly varying tapered shapes. Specifically, for bands of wavenumbers, peculiar gourd-like shapes were obtained as optimal shapes to maximize the power transmission coefficient. Numerical results from the proposed optimization formulation were also experimentally realized to verify the validity of the present designs.

Optimal Power Flow Modelling and Analysis of Hybrid AC-DC Grids with Offshore Wind Power Plant

DEFF Research Database (Denmark)

Dhua, Debasish; Huang, Shaojun; Wu, Qiuwei

2017-01-01

In order to develop renewables based energy systems, the installation of the offshore wind power plants (WPPs) is globally encouraged. However, wind power generation is intermittent and uncertain. An accurate modelling and evaluation reduces investment and provide better operation. Hence......, the wind power production level also plays a major role in a hybrid system on transmission loss evaluation. The developed model is tested in Low, Medium and High wind power production levels to determine the objective function of the OPF solution. MATLAB Optimization Toolbox and MATLAB script are used......, it is essential to develop a suitable model and apply optimization algorithms for different application scenarios. The objective of this work is to develop a generalized model and evaluate the Optimal Power Flow (OPF) solutions in a hybrid AC/DC system including HVDC (LCC based) and offshore WPP (VSC based...

Gait-Cycle-Driven Transmission Power Control Scheme for a Wireless Body Area Network.

Science.gov (United States)

Zang, Weilin; Li, Ye

2018-05-01

In a wireless body area network (WBAN), walking movements can result in rapid channel fluctuations, which severely degrade the performance of transmission power control (TPC) schemes. On the other hand, these channel fluctuations are often periodic and are time-synchronized with the user's gait cycle, since they are all driven from the walking movements. In this paper, we propose a novel gait-cycle-driven transmission power control (G-TPC) for a WBAN. The proposed G-TPC scheme reinforces the existing TPC scheme by exploiting the periodic channel fluctuation in the walking scenario. In the proposed scheme, the user's gait cycle information acquired by an accelerometer is used as beacons for arranging the transmissions at the time points with the ideal channel state. The specific transmission power is then determined by using received signal strength indication (RSSI). An experiment was conducted to evaluate the energy efficiency and reliability of the proposed G-TPC based on a CC2420 platform. The results reveal that compared to the original RSSI/link-quality-indication-based TPC, G-TPC reduces energy consumption by 25% on the sensor node and reduce the packet loss rate by 65%.

Induced voltages in metallic pipelines near power transmission lines

International Nuclear Information System (INIS)

Grcev, Leonid; Jankov, Voislav; Filiposki, Velimir

2002-01-01

With the continuous development of the electric power system and the pipeline networks used to convey oil or natural gas, cases of close proximity of high voltage structures and metallic pipelines become more and more frequent. Accordingly there is a growing concern about possible hazards resulting from voltages induced in the metallic pipelines by magnetic coupling with nearby power transmission lines. This paper presents a methodology for computation of the induced voltages in buried isolated metallic pipelines. A practical example of computation is also presented. (Author)

Relay selection in underlay cognitive networks with fixed transmission power nodes

KAUST Repository

Hussain, Syed Imtiaz

2013-07-31

Underlay cognitive networks operate simultaneously with primary networks satisfying stringent interference constraints, which reduces their transmission power and coverage area. To reach remote destinations, secondary sources use relaying techniques. Selecting the best relay among the available ones is a well known technique. Recently, selective cooperation is investigated in cognitive networks where the secondary nodes can adapt their transmission power to always satisfy the interference threshold. In this paper, we investigate a situation where the secondary nodes have a fixed transmission power and may violate the interference threshold. We present two relay selection schemes; the first one excludes the relays not satisfying the interference constraint and then picks up a relay from the remaining ones that can provide the maximum signal-to-noise ratio (SNR). The other scheme uses a quotient of the relay link SNR and the interference from the relay to the primary user and optimizes it to maximise the relay link SNR. We derive closed form expressions for outage probability, bit error rate, channel capacity and diversity of the system for both schemes by using tight approximations. We also study mutual effects of interference. Simulation results confirm the analytical results and reveal that the relay selection is feasible at low SNRs. Copyright © 2013 John Wiley & Sons, Ltd.

Aggregated Wind Park Models for Analysing Power System Dynamics

Energy Technology Data Exchange (ETDEWEB)

Poeller, Markus; Achilles, Sebastian [DIgSILENT GmbH, Gomaringen (Germany)

2003-11-01

The increasing amount of wind power generation in European power systems requires stability analysis considering interaction between wind-farms and transmission systems. Dynamics introduced by dispersed wind generators at the distribution level can usually be neglected. However, large on- and offshore wind farms have a considerable influence to power system dynamics and must definitely be considered for analyzing power system dynamics. Compared to conventional power stations, wind power plants consist of a large number of generators of small size. Therefore, representing every wind generator individually increases the calculation time of dynamic simulations considerably. Therefore, model aggregation techniques should be applied for reducing calculation times. This paper presents aggregated models for wind parks consisting of fixed or variable speed wind generators.

Wireless power and data transmission strategies for next-generation capsule endoscopes

International Nuclear Information System (INIS)

Puers, R; Carta, R; Thoné, J

2011-01-01

Capsular endoscopy is becoming increasingly popular as an alternative to traditional gastro-intestinal (GI) examination techniques. However, the breakthrough of these devices is hindered by the limited amount of power that can be stored in a tiny pill. Most commercial devices use two watch batteries that can only provide an average power of 25 mW for about 6 h, certainly not sufficient for advanced robotic features. A dedicated inductive powering system, operating at 1 MHz to limit the human body absorption, has been developed which was proven to support the transfer of over 300 mW. The system relies on a condensed set of orthogonal ferrite coils, embedded in the capsule, and an external unit based on a Helmholtz coil driven by a class E amplifier. Control data can be sent through the inductive link by modulating the power carrier, whereas a dedicated high data rate RF link is used to transfer the images from the capsule to the base station. Besides evaluating the compatibility with radio transmission, several demonstrators were assembled combining the wireless powering system with various locomotion strategies and LED illumination. This paper describes the design and implementation of the inductive powering system, its combination with data transmission techniques and the testing activity with other capsule-dedicated modules

Design of an effective energy receiving adapter for microwave wireless power transmission application

Directory of Open Access Journals (Sweden)

Peng Xu

2016-10-01

Full Text Available In this paper, we demonstrate the viability of an energy receiving adapter in a 8×8 array form with high power reception efficiency with the resonator of artificial electromagnetic absorber being used as the element. Unlike the conventional reported rectifying antenna resonators, both the size of the element and the separations between the elements are electrically small in our design. The energy collecting process is explained with an equivalent circuit model, and a RF combining network is designed to combine the captured AC power from each element to one main terminal for AC-to-DC conversion. The energy receiving adapter yields a total reception efficiency of 67% (including the wave capture efficiency of 86% and the AC-to-DC conversion efficiency of 78%, which is quite promising for microwave wireless power transmission.

Highly efficient solutions for smart and bulk power transmission of 'green energy'

Energy Technology Data Exchange (ETDEWEB)

Breuer, Wilfried; Retzmann, Dietmar; Uecker, Karl

2010-09-15

Environmental constraints, loss minimization and CO2 reduction will play an increasingly more important role in future. Security and sustainability of power supply as well as economic efficiency needs application of advanced technologies. Innovative solutions with HVDC (High Voltage Direct Current) and FACTS (Flexible AC Transmission Systems) have the potential to cope with these challenges. They provide the features which are necessary to avoid technical problems in power systems, they increase the transmission capacity and system stability very efficiently and help prevent cascading outages. Furthermore, they are essential for Grid Access of Renewable Energy Sources such as Hydro, Wind and Solar-Energy.

Economic Aspect of HVDC Transmission System for Indonesia Consideration in Nuclear Power Development

International Nuclear Information System (INIS)

Edwaren Liun

2009-01-01

As a country with hundreds million people, Indonesia needs to generate large scale power and distribute it to thorough country to improve gross domestic product of the population. In the power transmission domain, the High Voltage Direct Current (HVDC) transmission system should be considered for the next decades concerning any technical and economical problems with HVAC transmission. HVDC transmission system is the answer for the Indonesian condition. This system can connect the high energy potential regions to the high energy demand regions. HVDC is the most efficient to transport energy from one region to another one region. Dismantling and removing assets costs are included to the estimated for capital costs, while the environmental and property costs are the costs of securing designations and resource consents, and valuation and legal advice for the HVDC investment. Although converter terminals are expensive however, for long transmissions HVDC system can compensate the costs over breakeven distance through very efficient transmission system. Efficiency of HVDC is appearing from conductor wire, supporting tower, low energy loses and free space used by route of the transmission line. HVDC system is also free from some problem, concerning stability, inductive and capacitive load components, phase differences and frequency system. In the economic aspect the HVDC capital costs for the transmission options comprise estimates of the cost to design, purchase and construct new HVDC transmission components. While operating and maintenance costs of HVDC assets comprise the costs for replacement the old existing overhead transmission lines, underground and submarine cables, and HVDC converter station components. (author)

Models for the modern power grid

Science.gov (United States)

Nardelli, Pedro H. J.; Rubido, Nicolas; Wang, Chengwei; Baptista, Murilo S.; Pomalaza-Raez, Carlos; Cardieri, Paulo; Latva-aho, Matti

2014-10-01

This article reviews different kinds of models for the electric power grid that can be used to understand the modern power system, the smart grid. From the physical network to abstract energy markets, we identify in the literature different aspects that co-determine the spatio-temporal multilayer dynamics of power system. We start our review by showing how the generation, transmission and distribution characteristics of the traditional power grids are already subject to complex behaviour appearing as a result of the the interplay between dynamics of the nodes and topology, namely synchronisation and cascade effects. When dealing with smart grids, the system complexity increases even more: on top of the physical network of power lines and controllable sources of electricity, the modernisation brings information networks, renewable intermittent generation, market liberalisation, prosumers, among other aspects. In this case, we forecast a dynamical co-evolution of the smart grid and other kind of networked systems that cannot be understood isolated. This review compiles recent results that model electric power grids as complex systems, going beyond pure technological aspects. From this perspective, we then indicate possible ways to incorporate the diverse co-evolving systems into the smart grid model using, for example, network theory and multi-agent simulation.

Power transfer capability assessment of transmission interfaces with SVC and load shedding systems

Energy Technology Data Exchange (ETDEWEB)

Pavlovsky, V. [DMCC-Engineering, Kiev (Ukraine). Inst. of Electrodynamics; Dolzhenitsa, Y. [DMCC Engineering, Kiev (Ukraine); Ushapovskiy, K. [National Power Co. Ukrenergo, Kiev (Ukraine)

2009-07-01

As a result of deregulation in the power industry, energy trade and markets are pushing transmission system operators to operate their systems closer to the edge of the power transfer capability. Voltage instability and inadequate reactive power support of generators is a key factor in most major outages around the world. The ideal way to control power systems is to avoid emergencies by reliable planning and secure operation of power systems. Therefore, the accurate calculation of the power transfer capability of transmission interfaces is an important task on the planning and operation stages. This paper discussed the issue of transfer capability assessment and monitoring for interfaces with static var compensator (SVC) and load shedding schemes. It also proposed a special measure, a distance to voltage instability point, to monitor transfer capability on-line. The distance may be observed by measurement of SVC output. The paper considered the problem of optimal SVC size selection and a new approach was proposed based on P-V curves analysis. The paper discussed the problem formulation and proposed approach. A case was also presented in order to demonstrate the proposed approach on the IPS Ukraine-Crimea interface. It was concluded that the proposed approach allows the optimal rating of SVC for increasing transfers capability of transmission corridors. 12 refs., 9 figs.

A method of Modelling and Simulating the Back-to-Back Modular Multilevel Converter HVDC Transmission System

Science.gov (United States)

Wang, Lei; Fan, Youping; Zhang, Dai; Ge, Mengxin; Zou, Xianbin; Li, Jingjiao

2017-09-01

This paper proposes a method to simulate a back-to-back modular multilevel converter (MMC) HVDC transmission system. In this paper we utilize an equivalent networks to simulate the dynamic power system. Moreover, to account for the performance of converter station, core components of model of the converter station gives a basic model of simulation. The proposed method is applied to an equivalent real power system.

Re-thinking the power transmission model for sub-Saharan Africa

Energy Technology Data Exchange (ETDEWEB)

Sebitosi, A.B. [Center for Renewable and Sustainable Energy Studies, University of Stellenbosch, Matieland 7602 (South Africa); Okou, R. [Department of Electrical Engineering, University of Cape Town, Rondebosch 7701 (South Africa)

2010-03-15

A vision for a United States of Africa has been advocated since the dawn of independence by, among others, pioneers like Kwame Nkrumah, Gamal Abdel Nasser and Julius Nyerere. More recently the idea gained new momentum, through such initiatives as the New Partnership for African Development (NEPAD) and the African Union (AU) to create a single market of Africa's 750 million people that is competitive within itself and within the global economy. This would be achieved through a deliberate, systematic and concerted effort to integrate, upgrade and modernize infrastructure that would offer the required catalyst for economic growth. However, the prioritization by African policy makers of a grand plan to link up the entire African continent's electric power grid networks would appear to be incompatible with 21st century thinking. The specifications for a centrally managed power grid were made by Nicola Tesla in 1883 and have served the power industry for over 125 years but are now obsolete in the era of digital micro-electronics and smart grid concepts. This paper examines some issues that surround the evolution of sub-Sahara African regional power pools and highlights the anomalies and perhaps wrong timing around the conceptualization and prioritization of grand inter-state power grids. The authors then propose an alternative model that conforms to a new and more sustainable paradigm in electricity supply economics. The proposals are however not meant to provide a panacea but it is hoped that the article will ignite a debate that will lead to a lasting solution. (author)

Re-thinking the power transmission model for sub-Saharan Africa

International Nuclear Information System (INIS)

Sebitosi, A.B.; Okou, R.

2010-01-01

A vision for a United States of Africa has been advocated since the dawn of independence by, among others, pioneers like Kwame Nkrumah, Gamal Abdel Nasser and Julius Nyerere. More recently the idea gained new momentum, through such initiatives as the New Partnership for African Development (NEPAD) and the African Union (AU) to create a single market of Africa's 750 million people that is competitive within itself and within the global economy. This would be achieved through a deliberate, systematic and concerted effort to integrate, upgrade and modernize infrastructure that would offer the required catalyst for economic growth. However, the prioritization by African policy makers of a grand plan to link up the entire African continent's electric power grid networks would appear to be incompatible with 21st century thinking. The specifications for a centrally managed power grid were made by Nicola Tesla in 1883 and have served the power industry for over 125 years but are now obsolete in the era of digital micro-electronics and smart grid concepts. This paper examines some issues that surround the evolution of sub-Sahara African regional power pools and highlights the anomalies and perhaps wrong timing around the conceptualization and prioritization of grand inter-state power grids. The authors then propose an alternative model that conforms to a new and more sustainable paradigm in electricity supply economics. The proposals are however not meant to provide a panacea but it is hoped that the article will ignite a debate that will lead to a lasting solution.

Electric power transmission for a Hanford Nuclear Energy Center (HNEC)

International Nuclear Information System (INIS)

Harty, H.; Dowis, W.J.

1983-06-01

The original study of transmission for a Hanford Nuclear Energy Center (HNEC), which was completed in September 1975, was updated in June 1978. The present 1983 revision takes cognizance of recent changes in the electric power situation of the PNW with respect to: (1) forecasts of load growth, (2) the feasibility of early use of 1100 kV transmission, and (3) the narrowing opportunities for siting nuclear plants in the region. The purpose of this update is to explore and describe additions to the existing transmission system that would be necessary to accommodate three levels of generation at HNEC. Comparisons with a PNW system having new thermal generating capacity distributed throughout the marketing region are not made as was done in earlier versions

Comprehensive evaluation of power grid projects' investment benefits under the reform of transmission and distribution price

Science.gov (United States)

Wang, Yongli; Wang, Gang; Zuo, Yi; Fan, Lisha; Ling, Yunpeng

2017-03-01

On March 15, 2015, the Central Office issued the "Opinions on Further Deepening the Reform of Electric Power System" (Zhong Fa No. 9). This policy marks the central government officially opened a new round of electricity reform. As a programmatic document under the new situation to comprehensively promote the reform of the power system, No. 9 document will be approved as a separate transmission and distribution of electricity prices, which is the first task of promoting the reform of the power system. Grid tariff reform is not only the transmission and distribution price of a separate approval, more of the grid company input-output relationship and many other aspects of deep-level adjustments. Under the background of the reform of the transmission and distribution price, the main factors affecting the input-output relationship, such as the main business, electricity pricing, and investment approval, financial accounting and so on, have changed significantly. The paper designed the comprehensive evaluation index system of power grid projects' investment benefits under the reform of transmission and distribution price to improve the investment efficiency of power grid projects after the power reform in China.

Initial assessment: electromagnetic compatibility aspects of proposed SPS Microwave Power Transmission System (MPTS) operations

Energy Technology Data Exchange (ETDEWEB)

1978-02-01

An analysis of major concerns with regard to the effects on radio and electronic systems by the proposed Microwave Power Transmission System for transmitting power from a satellite solar power station to earth is presented. (LCL)

On modelling, simulation and measurement of fluid power pumps and pipelines

International Nuclear Information System (INIS)

Weddfelt, K.

1992-01-01

Pressure ripple in fluid power systems is often considered to be a nuisance. It is a major reason for vibrations and noise emission but can also cause functional problems, in extreme causes even fatigue and breakdown of pipes and connections. In order to examine this problem both the sources of pressure ripple and its transmission properties must be considered. A major source of pressure ripple in fluid power systems is positive displacement pumps, a component which is actually a source of flow ripple. A positive displacement pump can be characterized and modelled as a flow source with an internal source impedance. Special measurement techniques must be developed in order to determine these source properties experimentally. Pressure and flow ripple propagate through the pipeline of a fluid power system as waves. When the impedance of the system changes, part of the energy in the wave is being transmitted while the remaining part is reflected. Therefore, the mechanism for standing waves to occur is present, causing resonances and possibly very large pressure pulsations at certain frequencies. Destructive interference between these waves can be used to design so-called reactive attenuators, similar to an automobile muffler, which can be used to acoustically separate the source of flow ripple from the rest of the fluid power system. A mathematical model of wave transmission in pipelines is of fundamental importance to the design of acoustical sound systems. It is of equal importance when modelling and measuring the source characteristics of fluid power pumps. Such a mathematical model must include the transmission and reflection of waves as well as the frequency-dependent losses from viscous friction in the fluid. (au)

Modeling and power system stability of VSC-HVDC systems for grid-connection of large offshore windfarms

Energy Technology Data Exchange (ETDEWEB)

Xue Yijing [Vestas China, Beijing (China); Akhmatov, Vladislav [Technical Univ. of Denmark, Lyngby (Denmark). Centre for Electric Technology

2009-07-01

Utilization of Voltage Source Converter (VSC) - High Voltage Direct Current (HVDC) systems for grid-connection of large offshore windfarms becomes relevant as installed power capacities as well as distances to the connection points of on-land transmission systems increase. At the same time, the grid code requirements of the Transmission System Operators (TSO), including ancillary system services and Low-Voltage Fault-Ride-Through (LVFRT) capability of large offshore windfarms, become more demanding. This paper presents a general-level model of and a LVFRT solution for a VSC-HVDC system for grid-connection of large offshore windfarms. The VSC-HVDC model is implemented using a general approach of independent control of active and reactive power in normal operations. The on-land VSC inverter, i.e. a grid-side inverter, provides voltage support to the transmission system and comprises a LVFRT solution in short-circuit faults. The presented model, LVFRT solution and impact on the system stability are investigated as a case study of a 1,000 MW offshore windfarm grid-connected through a VSC-HVDC system. The investigation is carried out on a model of the west Danish, with some elements of the north German, 400 kV, 220 kV and 150 kV transmission systems stage 2005-2006 using the DIgSILENT PowerFactory simulation program. In the investigation, a thermal power plant just south to the Danish border has been substituted by this 1,000 MW offshore windfarm utilizing the VSC-HVDC system. The investigation has shown that the substitution of a thermal power plant by a VSC-HVDC connected offshore windfarm should not have any negative impact on the short-term stability of the west Danish transmission system. The investigation should be repeated applying updated system model stages and offshore wind power commissioning schedules in the North and Baltic Seas. (orig.)

Power Transmission from Large Offshore Wind Farms

DEFF Research Database (Denmark)

Pedersen, Jørgen Kaas

1999-01-01

The major part of the coming wind farms in Denmark will be placed offshore. If the location is near a grid with a high short circuit level the power can be transmitted as AC.If the wind farm is far away from the grid and the grid perhaps has a low short circuit level, the best solution...... for transmitting the power can be by DC. At the moment it is possible to build self-commutating DC/AC-inverters up to about 150 kV. This paper will show a concept to a solution for a wind farm and a transmission system based on synchronous generators or a powerformer® with a rated voltage of 50 kV. The AC power...... will be rectified and boosted to a fixed DC voltage (e.g. 100 kV). The speed of the generator will be variable, depending of the wind but also controlled with the duty-cycle of the booster. In that way all wind turbines can be connected to the same DC bus and the cable to the inverter station connected to the AC...

Ranking transmission projects in large scale systems using an AC power flow model; Priorizacao de obras em sistemas de grande porte usando um modelo AC da rede

Energy Technology Data Exchange (ETDEWEB)

Melo, A C.G. [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil); Fontoura Filho, R N [ELETROBRAS, Rio de Janeiro, RJ (Brazil); Peres, L A.P. Pecorelli [FURNAS, Rio de Janeiro, RJ (Brazil); Morozowski Filho, M [Santa Catarina Univ., Florianopolis, SC (Brazil)

1994-12-31

Initially, this paper summarizes the approach developed by the Brazilian Planning Criteria Working Group (GTCP/ELETROBRAS) for identifying which subset of transmission investments should be postponed to meet a pre-stablished budget constraint with the least possible impact on system performance. Next, this paper presents the main features of the computational model PRIO, which allows the application of the ranking process to large scale power systems (2,000 buses and 3,000 circuits), with as many as 100 projects to be ranked. In this model, the adequacy analysis of each system state is carried out through an AC power flow coupled to a successive linear programming based remedial actions model. Case studies with the IEEE-RTS system and a configuration of the Brazilian Southeastern are presented and discussed. (author) 7 refs., 6 figs., 5 tabs.

Economic assessment group on power transmission and distribution networks tariffs

International Nuclear Information System (INIS)

2000-06-01

Facing the new law on the electric power market liberalization, the french government created an experts group to analyze solutions and assessment methods of the electrical networks costs and tariffs and to control their efficiency. This report presents the analysis and the conclusions of the group. It concerns the three main subjects: the regulation context, the tariffing of the electric power transmission and distribution (the cost and efficiency of the various options) and the tariffing of the electric power supply to the eligible consumers. The authors provide a guideline for a tariffing policy. (A.L.B.)

Modeling of power train by applying the virtual prototype concept; Kaso genkei ni yoru power train no model ka

Energy Technology Data Exchange (ETDEWEB)

Hiramatsu, S; Harada, Y; Arakawa, H; Komori, S [Mazda Motor Corp., Hiroshima (Japan); Sumida, S [U-Shin Corp., Tokyo (Japan)

1997-10-01

This paper describes the simulation of power train that includes the model developed by applying the virtual prototype concept. By this concept, subsystem models which consist of functional model and mechanism models are integrated into a total system model. This peculiarity in architecture of model, which is called the hierarchical structure, enables us to model a system of large scale with many units, systems and parts easily. Two kinds of computer simulations are performed. One is engine revolution fluctuation by accessory load input, and the other is changing gears by automatic transmission. They are verified to have sufficient accuracy. 2 refs., 12 figs.

Third generation hybrid drive. Transmission-based integration of power electronics; Dritte Generation Hybridantrieb. Getriebenahe Integration der Leistungselektronik

Energy Technology Data Exchange (ETDEWEB)

Schoen, Wolfgang [ZF Friedrichshafen AG, Friedrichshafen (DE). Hybridantriebe (F und E); Lutz, Steffen [BMW AG, Muenchen (Germany); Hensler, Alexander [Technische Univ. Chemnitz (Germany); Munding, Andreas [Liebherr Elektronik GmbH, Lindau (Germany); Thoben, Markus [Infineon Technologies AG, Warstein (Germany); Zeidler, Dietmar [Kemet Electronics GmbH, Landsberg am Lech (Germany)

2011-06-15

The power electronics components in today's hybrid vehicles are situated at different places in the vehicle - till now far away from harsh and hot surroundings. In order to develop an integrated solution near the transmission, ZF and BMW launched the research project 'Electric components for active power transmissions' (EfA). On the basis of an eight-speed full hybrid transmission and together with Infineon, Kemet, Liebherr, and the University of Technology of Chemnitz, they are developing a power electronics unit, which facilitates doubling the power density while increasing the operating temperature. The project EfA will be concluded in June 2011. (orig.)

Improvement of the electric power sector through the access to the national power transmission system - SINTREL (Brazilian National System of Electric Power Transmission); Aperfeicoamento do setor de energia eletrica atraves do acesso a transmissao - SINTREL (Sistema Nacional de Transmissao de Energia Eletrica)

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-04-01

This report presents the organization and the operation of SINTREL (Brazilian National System of Electric Power Transmission), the national power transmission system, and it defines its function in the process of reform of the Brazilian electric sector. Besides showing the traditional organization of the companies and of the electric system, and the evolution of the organization of the Brazilian electric system to favor the competition.

Mathematical models for lymphatic filariasis transmission and control: Challenges and prospects

Directory of Open Access Journals (Sweden)

Kaliannagounder Krishnamoorthy

2008-02-01

Full Text Available Abstract Background Mathematical models developed for describing the dynamics of transmission, infection, disease and control of lymphatic filariasis (LF gained momentum following the 1997 World Health Assembly resolution and the launching of the Global Programme to Eliminate Lymphatic Filariasis (GPELF in 2000. Model applications could provide valuable inputs for making decisions while implementing large scale programmes. However these models need to be evaluated at different epidemiological settings for optimization and fine-tuning with new knowledge and understanding on infection/disease dynamics. Discussion EPIFIL and LYMFASIM are the two mathematical simulation models currently available for lymphatic filariasis transmission and control. Both models have been used for prediction and evaluation of control programmes under research settings. Their widespread application in evaluating large-scale elimination programmes warrants validation of assumptions governing the dynamics of infection and disease in different epidemiological settings. Furthermore, the predictive power of the models for decision support can be enhanced by generating knowledge on some important issues that pose challenges and incorporating such knowledge into the models. We highlight factors related to the efficacy of the drugs of choice, their mode of action, and the possibility that drug resistance may develop; the role of vector-parasite combinations; the magnitude of transmission thresholds; host-parasite interactions and their effects on the dynamics of infection and immunity; parasite biology, and progression to LF-associated disease. Summary The two mathematical models developed offer potential decision making tools for transmission and control of LF. In view of the goals of the GPELF, the predictive power of these models needs to be enhanced for their wide-spread application in large scale programmes. Assimilation and translation of new information into the models is

Simulation model of the transmission grid for a large offshore windfarm, used in education and research st the Technical University of Denmark

Energy Technology Data Exchange (ETDEWEB)

Akhmatov, V.; Nielsen, A.H.

2006-05-15

A small test software-model for the transmission system containing a number of central power plants, consumption centres, local wind turbines and a large offshore windfarm has been implemented in the simulation tool Powerfactory (DigSilent). This model demonstrates the interaction between electricity-producing wind turbines and a realistic transmission system, for instance short-term voltage stability and ride-through capability of the wind turbines. The model has been developed by the Danish Transmission System Operator Energinet.dk for use by the Centre for Electric Technology (CET) at Technical University of Denmark. It has been applied in the education of electric power engineers and in research projects. An example of its use is presented. [Author].

Load-Sharing Characteristics of Power-Split Transmission System Based on Deformation Compatibility and Loaded Tooth Contact Analysis

Directory of Open Access Journals (Sweden)

Hao Dong

2015-01-01

Full Text Available In order to implement the uniform load distribution of the power-split transmission system, a pseudostatic model is built. Based on the loaded tooth contact analysis (LTCA technique, the actual meshing process of each gear pair is simulated and the fitting curve of time-varying mesh stiffness is obtained. And then, the torsional angle deformation compatibility conditions are proposed according to the closed-loop characteristic of power flow, which will be combined with the torque equilibrium conditions and elastic support conditions to calculate the transfer torque of each gear pair. Finally, the load-sharing coefficient of the power-split transmission system is obtained, and the influences of the installation errors are analyzed. The results show that the above-mentioned installation errors comprehensively influence the load-sharing characteristics, and the reduction of only one error could not effectively achieve perfect load-sharing characteristics. Allowing for the spline clearance floating and constrained by the radial spacing ring, the influence of the floating pinion is analyzed. It shows that the floating pinion can improve the load-sharing characteristics. Through the comparison between the theoretical and related experimental data, the reasonability and feasibility of the above-proposed method and model are verified.

75 FR 81264 - Critical Path Transmission, LLC; Clear Power, LLC; v. California Independent System Operator, Inc...

Science.gov (United States)

2010-12-27

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL11-11-000] Critical Path Transmission, LLC; Clear Power, LLC; v. California Independent System Operator, Inc.; Notice of Complaint... and 306 of the Federal Power Act, 16 U.S.C. 824e and 825e (2006), Critical Path Transmission, LLC and...

Modeling of spectral atmosphere transmission for infrared radiation

International Nuclear Information System (INIS)

Wiecek, B.; Olbrycht, R.

2009-01-01

IR radiation transmission of the atmosphere is an important factor during the thermovision remote sensing and measurement. Transmission coefficient of the atmosphere depends on its content and it is attenuated mainly due to the vapor concentration. Every calibrated thermal camera should be equipped with the digital system which implements the transmission model of the atmosphere. The model presented in this work is based on Beer and Bouguer laws. The proposed simplified model of transmission atmosphere is suitable for implementation in the thermal cameras. A simple digital controller of the camera can calculate the transmission coefficient and correct the temperature measurement. The model takes in account both scattering and absorption due the quantum effects when the photons are interacting with the molecules. (author)

An Optimal Joint User Association and Power Allocation Algorithm for Secrecy Information Transmission in Heterogeneous Networks

Directory of Open Access Journals (Sweden)

Rong Chai

2017-01-01

Full Text Available In recent years, heterogeneous radio access technologies have experienced rapid development and gradually achieved effective coordination and integration, resulting in heterogeneous networks (HetNets. In this paper, we consider the downlink secure transmission of HetNets where the information transmission from base stations (BSs to legitimate users is subject to the interception of eavesdroppers. In particular, we stress the problem of joint user association and power allocation of the BSs. To achieve data transmission in a secure and energy efficient manner, we introduce the concept of secrecy energy efficiency which is defined as the ratio of the secrecy transmission rate and power consumption of the BSs and formulate the problem of joint user association and power allocation as an optimization problem which maximizes the joint secrecy energy efficiency of all the BSs under the power constraint of the BSs and the minimum data rate constraint of user equipment (UE. By equivalently transforming the optimization problem into two subproblems, that is, power allocation subproblem and user association subproblem of the BSs, and applying iterative method and Kuhn-Munkres (K-M algorithm to solve the two subproblems, respectively, the optimal user association and power allocation strategies can be obtained. Numerical results demonstrate that the proposed algorithm outperforms previously proposed algorithms.

Islanding the power grid on the transmission level: less connections for more security

Science.gov (United States)

Mureddu, Mario; Caldarelli, Guido; Damiano, Alfonso; Scala, Antonio; Meyer-Ortmanns, Hildegard

2016-10-01

Islanding is known as a management procedure of the power system that is implemented at the distribution level to preserve sensible loads from outages and to guarantee the continuity in electricity supply, when a high amount of distributed generation occurs. In this paper we study islanding on the level of the transmission grid and shall show that it is a suitable measure to enhance energy security and grid resilience. We consider the German and Italian transmission grids. We remove links either randomly to mimic random failure events, or according to a topological characteristic, their so-called betweenness centrality, to mimic an intentional attack and test whether the resulting fragments are self-sustainable. We test this option via the tool of optimized DC power flow equations. When transmission lines are removed according to their betweenness centrality, the resulting islands have a higher chance of being dynamically self-sustainable than for a random removal. Less connections may even increase the grid’s stability. These facts should be taken into account in the design of future power grids.

Artificial neural networks to estimate the EMF ELF on car travelling near power transmission line

Energy Technology Data Exchange (ETDEWEB)

Al-Sayegh, O.A.; Qabazard, A.M. [Kuwait Inst. for Scientific Research, Safat (Kuwait). advanced Systems Division of Environment and Urban

2007-07-01

An artificial neural network (ANN) was developed to determine the electromagnetic field (EMF) and extremely low frequency (ELF) intensity on a vehicle body at different distances from a high tension power line and at varying power loads. EMF radiated emissions from ELF source power transmission lines can produce interference in the electric components in vehicles traveling at variable speed near the power lines. The passengers in the vehicle may also experience EMF-related health problems. Although EMF has been recently categorized as a new form of pollution, the situation has been largely ignored by the industry. Typically, electromagnetic fields at different frequencies show the fastest growing environmental influences. All populations are now exposed to varying degrees of EMF and the levels will continue to increase as technology advances. The purpose of this work was to promote discussion and help find design solutions to manufacture a new device for measuring the EMF at variable speed. In this study, a set of near field measurements outside the vehicle were used to train ANN. Estimations of the EMF ELF for various distances from the high tension power line were presented. It was determined that the most important factors affecting the electric field model include exposure conditions; size, shape and position of the exposed body in the field; and, surface charge density. The EMF ELF was found to increase near sagging areas of the overhead power transmission line. The EMF ELF was found to be proportional to the total amps flowing through the line at the time of measurement. 14 refs., 3 figs.

Modeling of MEMS piezoelectric energy harvesters using electromagnetic and power system theories

International Nuclear Information System (INIS)

Ahmad, Mahmoud Al; Alshareef, H N; Elshurafa, Amro M; Salama, Khaled N

2011-01-01

This work proposes a novel methodology for estimating the power output of piezoelectric generators. An analytical model that estimates for the first time the loss ratio and output power of piezoelectric generators based on the direct mechanical-to-electrical analogy, electromagnetic theory, and power system theory is developed. The mechanical-to-electrical analogy and power system theory allow the derivation of an equivalent input impedance expression for the network, whereas electromagnetic transmission line theory allows deduction of the equivalent electromechanical loss of the piezoelectric generator. By knowing the mechanical input power and the loss of the network, calculation of the output power of the piezoelectric device becomes a straightforward procedure. Experimental results based on published data are also presented to validate the analytical solution. In order to fully benefit from the well-established electromagnetic transmission line and electric circuit theories, further analyses on the resonant frequency, bandwidth, and sensitivity are presented. Compared to the conventional modeling methods currently being adopted in the literature, the proposed method provides significant additional information that is crucial for enhanced device operation and quick performance optimization

Low-latency video transmission over high-speed WPANs based on low-power video compression

DEFF Research Database (Denmark)

Belyaev, Evgeny; Turlikov, Andrey; Ukhanova, Ann

2010-01-01

This paper presents latency-constrained video transmission over high-speed wireless personal area networks (WPANs). Low-power video compression is proposed as an alternative to uncompressed video transmission. A video source rate control based on MINMAX quality criteria is introduced. Practical...

Proximity effects of high voltage electric power transmission lines on ...

African Journals Online (AJOL)

The proximity effects of high voltage electric power transmission lines on Leyland Cypress (xCupressocyparis leylandii (Dallim. and A.B. Jacks.) Dallim) and Japanese Privet (Ligustrum japonicum Thunb.) growth were examined in a private nursery located in Sakarya, Turkey. Five transect were randomly chosen in both ...

Distributed decision-making in electric power system transmission maintenance scheduling using multi-agent systems (MAS)

Science.gov (United States)

Zhang, Zhong

In this work, motivated by the need to coordinate transmission maintenance scheduling among a multiplicity of self-interested entities in restructured power industry, a distributed decision support framework based on multiagent negotiation systems (MANS) is developed. An innovative risk-based transmission maintenance optimization procedure is introduced. Several models for linking condition monitoring information to the equipment's instantaneous failure probability are presented, which enable quantitative evaluation of the effectiveness of maintenance activities in terms of system cumulative risk reduction. Methodologies of statistical processing, equipment deterioration evaluation and time-dependent failure probability calculation are also described. A novel framework capable of facilitating distributed decision-making through multiagent negotiation is developed. A multiagent negotiation model is developed and illustrated that accounts for uncertainty and enables social rationality. Some issues of multiagent negotiation convergence and scalability are discussed. The relationships between agent-based negotiation and auction systems are also identified. A four-step MAS design methodology for constructing multiagent systems for power system applications is presented. A generic multiagent negotiation system, capable of inter-agent communication and distributed decision support through inter-agent negotiations, is implemented. A multiagent system framework for facilitating the automated integration of condition monitoring information and maintenance scheduling for power transformers is developed. Simulations of multiagent negotiation-based maintenance scheduling among several independent utilities are provided. It is shown to be a viable alternative solution paradigm to the traditional centralized optimization approach in today's deregulated environment. This multiagent system framework not only facilitates the decision-making among competing power system entities, but

Improvement The Transmission Efficiency For Wireless Packet Communication Systems Using Automatic Control for power And Time Slot Width Of Slotted Non persistent ISMA Protocol

Directory of Open Access Journals (Sweden)

Saad M. Hardan

2013-05-01

Full Text Available In packed communication systems which use a protocol, the protocol should perform the allocation of channels such that the transmission channel is used efficiently. Efficiency is usually measured in terms of channel throughput and the average transmission  delay. The Slotted Nonpersistent ISMA protocol is one of random access protocols used in packed communication systems. In this research a Slotted Nonpersistent ISMA protocol Model with automatic control for power and time slot is proposed. the suggested algorithm enable the base station(access point to control  the protocol time slot length and  transmission power in a dynamic way to control the normalized propagation delay d and to maintain all the uplink signals in the limit of captured power threshold (capture ratio in order to control the  throughput and the average transmission delay of the communication system by an automatic method. the computer simulation results  confirm the activity of the  proposed algorithm for increasing the  throughput and decreasing the average transmission delay by an accepted ratios.

Studying the Impact of Distributed Solar PV on Power Systems using Integrated Transmission and Distribution Models: Preprint

Energy Technology Data Exchange (ETDEWEB)

Jain, Himanshu [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Palmintier, Bryan S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Krad, Ibrahim [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Krishnamurthy, Dheepak [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-08-24

This paper presents the results of a distributed solar PV impact assessment study that was performed using a synthetic integrated transmission (T) and distribution (D) model. The primary objective of the study was to present a new approach for distributed solar PV impact assessment, where along with detailed models of transmission and distribution networks, consumer loads were modeled using the physics of end-use equipment, and distributed solar PV was geographically dispersed and connected to the secondary distribution networks. The highlights of the study results were (i) increase in the Area Control Error (ACE) at high penetration levels of distributed solar PV; and (ii) differences in distribution voltages profiles and voltage regulator operations between integrated T&D and distribution only simulations.

Fault Management of a Cold Dielectric HTS Power Transmission Cable

International Nuclear Information System (INIS)

Maguire, J; Allais, A; Yuan, J; Schmidt, F; Hamber, F; Welsh, Tom

2006-01-01

High temperature superconductor (HTS) power transmission cables offer significant advantages in power density over conventional copper-based cables. As with conventional cables, HTS cables must be safe and reliable when abnormal conditions, such as local and through faults, occur in the power grid. Due to the unique characteristics of HTS power cables, the fault management of an HTS cable is different from that of a conventional cable. Issues, such as nitrogen bubble formation within lapped dielectric material, need to be addressed. This paper reviews the efforts that have been performed to study the fault conditions of a cold dielectric HTS power cable. As a result of the efforts, a fault management scheme has been developed, which provides both local and through faults system protection. Details of the fault management scheme with examples are presented

Practical Coupled Resonators in Domino Arrangements for Power Transmission and Distribution: Replacing Step-Down Power Transformers and Their Branches across the Power Grid

Directory of Open Access Journals (Sweden)

Athanasios G. Lazaropoulos

2013-01-01

Full Text Available This paper considers the potential of replacing step-down power transformers of the entire power grid as well as part of their transmission line branches with wireless power transfer (WPT technology components. Exploiting the state-of-the-art evolutions in the fields of WPT technology, coupled resonators in domino arrangements—domino coupled resonator (DCR configurations—are proposed as suitable technological substitute for step-down power transformers and are investigated in terms of performance metrics such as power transfer efficiency (PTE and transformation ratio (TR. The contribution of this paper is fivefold. First, an analytical theoretical analysis appropriate to the study of practical DCR configurations is demonstrated. In order to support the DCR configuration replacement venture, a detailed set of assumptions regarding efficient mid- and long-range high-power WPTs as well as related technical issues is first presented. The validity of the theoretical analysis is verified through experimental measurements. Second, applying the proposed theoretical analysis, a wealth of system parameters that mainly influences the PTE and TR of DCR configurations is identified. Their quantitative effect as well as corresponding DCR configuration adjustments are first presented. Third, an approximate method, denoted as approximate chain scattering matrix (CSM method, is first introduced. Based on the scattering matrix theory formalism, the approximate CSM method is suitable for mid- and long-range DCR configurations when the theoretical analysis becomes computationally slow. The numerical results of approximate CSM method are compared with the respective ones of theoretical analysis validating the extent and the accuracy of approximate CSM method. Fourth, the potential of power transformer replacement with practical DCR configurations is thoroughly investigated in terms of their TRs. A plethora of high-voltage/medium-voltage (HV/MV, MV

Solar pumped laser technology options for space power transmission

Science.gov (United States)

Conway, E. J.

1986-01-01

An overview of long-range options for in-space laser power transmission is presented. The focus is on the new technology and research status of solar-pumped lasers and their solar concentration needs. The laser options include gas photodissociation lasers, optically-pumped solid-state lasers, and blackbody-pumped transfer lasers. The paper concludes with a summary of current research thrusts.

Multiarea Transmission Cost Allocation in Large Power Systems Using the Nodal Pricing Control Approach

Directory of Open Access Journals (Sweden)

M. Ghayeni

2010-12-01

Full Text Available This paper proposes an algorithm for transmission cost allocation (TCA in a large power system based on nodal pricing approach using the multi-area scheme. The nodal pricing approach is introduced to allocate the transmission costs by the control of nodal prices in a single area network. As the number of equations is dependent on the number of buses and generators, this method will be very time consuming for large power systems. To solve this problem, the present paper proposes a new algorithm based on multi-area approach for regulating the nodal prices, so that the simulation time is greatly reduced and therefore the TCA problem with nodal pricing approach will be applicable for large power systems. In addition, in this method the transmission costs are allocated to users more equitable. Since the higher transmission costs in an area having a higher reliability are paid only by users of that area in contrast with the single area method, in which these costs are allocated to all users regardless of their locations. The proposed method is implemented on the IEEE 118 bus test system which comprises three areas. Results show that with application of multi-area approach, the simulation time is greatly reduced and the transmission costs are also allocated to users with less variation in new nodal prices with respect to the single area approach.

Modeling generalized interline power-flow controller (GIPFC using 48-pulse voltage source converters

Directory of Open Access Journals (Sweden)

Amir Ghorbani

2018-05-01

Full Text Available Generalized interline power-flow controller (GIPFC is one of the voltage-source controller (VSC-based flexible AC transmission system (FACTS controllers that can independently regulate the power-flow over each transmission line of a multiline system. This paper presents the modeling and performance analysis of GIPFC based on 48-pulsed voltage-source converters. This paper deals with a cascaded multilevel converter model, which is a 48-pulse (three levels voltage source converter. The voltage source converter described in this paper is a harmonic neutralized, 48-pulse GTO converter. The GIPFC controller is based on d-q orthogonal coordinates. The algorithm is verified using simulations in MATLAB/Simulink environment. Comparisons between unified power flow controller (UPFC and GIPFC are also included. Keywords: Generalized interline power-flow controller (GIPFC, Voltage source converter (VCS, 48-pulse GTO converter

Overview of FACTS devices for wind power plants directly connected to the transmission network

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz; Teodorescu, Remus; Rodriguez, Pedro

2010-01-01

Growing number of wind turbines is changing electricity generation profile all over the world. This brings challenges for power system operation, which was designed and developed around conventional power plants with directly coupled synchronous generators. In result, safety and stability...... of the electrical network with high wind energy penetration might be compromised. For this reason transmission system operators (TSO) impose more stringent connection requirements on the wind power plant (WPP) owners. On the other hand flexible AC transmission systems (FACTS) devices offer enhancement of grid...... research in FACTS applicability for WPPs is summarized. Examples of few existing FACTS applications for wind farms are given....

47 CFR 74.795 - Digital low power TV and TV translator transmission system facilities.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Digital low power TV and TV translator... DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.795 Digital low power TV and TV translator transmission system facilities. (a) A digital low power TV or TV translator station shall operate...

Optimizing agent-based transmission models for infectious diseases.

Science.gov (United States)

Willem, Lander; Stijven, Sean; Tijskens, Engelbert; Beutels, Philippe; Hens, Niel; Broeckhove, Jan

2015-06-02

Infectious disease modeling and computational power have evolved such that large-scale agent-based models (ABMs) have become feasible. However, the increasing hardware complexity requires adapted software designs to achieve the full potential of current high-performance workstations. We have found large performance differences with a discrete-time ABM for close-contact disease transmission due to data locality. Sorting the population according to the social contact clusters reduced simulation time by a factor of two. Data locality and model performance can also be improved by storing person attributes separately instead of using person objects. Next, decreasing the number of operations by sorting people by health status before processing disease transmission has also a large impact on model performance. Depending of the clinical attack rate, target population and computer hardware, the introduction of the sort phase decreased the run time from 26% up to more than 70%. We have investigated the application of parallel programming techniques and found that the speedup is significant but it drops quickly with the number of cores. We observed that the effect of scheduling and workload chunk size is model specific and can make a large difference. Investment in performance optimization of ABM simulator code can lead to significant run time reductions. The key steps are straightforward: the data structure for the population and sorting people on health status before effecting disease propagation. We believe these conclusions to be valid for a wide range of infectious disease ABMs. We recommend that future studies evaluate the impact of data management, algorithmic procedures and parallelization on model performance.

Location-based Relay Selection and Power Adaptation Enabling Simultaneous Transmissions

DEFF Research Database (Denmark)

Nielsen, Jimmy Jessen; Madsen, Tatiana Kozlova; Schwefel, Hans-Peter

2010-01-01

Relaying is a well known technique to extend coverage and improve conditions for nodes in the outer coverage region. In this paper we propose a relaying scheme that exploits the spatial separation of relay and destination pairs to improve throughput by allowing simultaneous transmissions....... The proposed scheme is a cross-layer optimization for two-hop relaying that uses position information to jointly optimize relay selection and relay transmit power, maximizing Medium Access Control layer throughput. Further, in order to calculate the expected throughput, we apply a probabilistic model...... that takes into account MAC retransmissions and timing behavior of the IEEE 802.11 Distributed Coordination Function mode. Our results show an increase in throughput of approximately 20% is achievable for the proposed scheme when compared to two-hop relaying in the analyzed scenario....

Transmission Line Series Compensation for Wind Energy Transmission

International Nuclear Information System (INIS)

Palanichamy, C; Wong, Y C

2015-01-01

Wind energy has demonstrated to be a clean, copious and absolutely renewable source of energy, and the large penetration of it into the power grid indicates that wind energy is considered an effective means of power generation, Transmission of wind energy from remote locations to load centers necessitates long transmission lines. Series compensation is a proven and economical transmission solution to address system power transfer strength, grid stability, and voltage profile issues of long transmission lines. In this paper, a programmable approach to determine the capacitive reactance of series capacitor and optimum location for its placement to achieve maximum power transfer gas been presented. The respective program with sample solutions has been provided for real-time applications. (paper)

A Space Cam Mechanism for Power Transmission of an Opposite-cylinder Piston Engine

Directory of Open Access Journals (Sweden)

Zhang Haoyue

2015-01-01

Full Text Available For the purpose of improving the engine’s power density, we put forward a new type of power transmission mechanism which is used for opposed-cylinder engine. The gas pressure acts on the cam through the piston and push rod, and the spindle rotation of external is driven by the cam. The design of spatial cam work surface is completed by using the enveloping theory of a family of space curves, the force between roller and cam is analyzed using dynamic analysis software. Under the condition of equal number, size and stroke of piston, the new one with larger power density is more compact in structure than the traditional power transmission mechanism, and the reaction force on either side of the main shaft and the acting force between pistons and cylinders are smaller than those in traditional one, which prolongs the service life of the pistons.

8th international workshop on large-scale integration of wind power into power systems as well as on transmission networks for offshore wind farms. Proceedings

International Nuclear Information System (INIS)

Betancourt, Uta; Ackermann, Thomas

2009-01-01

Within the 8th International Workshop on Large-Scale Integration of Wind Power into Power Systems as well as on Transmission Networks for Offshore Wind Farms at 14th to 15th October, 2009 in Bremen (Federal Republic of Germany), lectures and posters were presented to the following sessions: (1) Keynote session and panel; (2) Grid integration studies and experience: Europe; (3) Connection of offshore wind farms; (4) Wind forecast; (5) High voltage direct current (HVDC); (6) German grid code issues; (7) Offshore grid connection; (8) Grid integration studies and experience: North America; (9) SUPWIND - Decision support tools for large scale integration of wind; (10) Windgrid - Wind on the grid: An integrated approach; (11) IEA Task 25; (12) Grid code issues; (13) Market Issues; (14) Offshore Grid; (15) Modelling; (16) Wind power and storage; (17) Power system balancing; (18) Wind turbine performance; (19) Modelling and offshore transformer.

Miniaturized Human Insertable Cardiac Monitoring System with Wireless Power Transmission Technique

Directory of Open Access Journals (Sweden)

Jong-Ha Lee

2016-01-01

Full Text Available Prolonged monitoring is more likely to diagnose atrial fibrillation accurately than intermittent or short-term monitoring. In this study, an implantable electrocardiograph (ECG sensor to monitor atrial fibrillation patients in real time was developed. The implantable sensor is composed of a micro controller unit, an analog-to-digital converter, a signal transmitter, an antenna, and two electrodes. The sensor detects ECG signals from the two electrodes and transmits these to an external receiver carried by the patient. Because the sensor continuously transmits signals, its battery consumption rate is extremely high; therefore, the sensor includes a wireless power transmission module that allows it to charge wirelessly from an external power source. The integrated sensor has the approximate dimensions 3 mm × 4 mm × 14 mm, which is small enough to be inserted into a patient without the need for major surgery. The signal and power transmission data sampling rate and frequency of the unit are 300 samples/s and 430 Hz, respectively. To validate the developed sensor, experiments were conducted on small animals.

Calculation of Voltages in Electric Power Transmission Lines During Historic Geomagnetic Storms: An Investigation Using Realistic Earth Impedances

Science.gov (United States)

Lucas, Greg M.; Love, Jeffrey J.; Kelbert, Anna

2018-02-01

Commonly, one-dimensional (1-D) Earth impedances have been used to calculate the voltages induced across electric power transmission lines during geomagnetic storms under the assumption that much of the three-dimensional structure of the Earth gets smoothed when integrating along power transmission lines. We calculate the voltage across power transmission lines in the mid-Atlantic region with both regional 1-D impedances and 64 empirical 3-D impedances obtained from a magnetotelluric survey. The use of 3-D impedances produces substantially more spatial variance in the calculated voltages, with the voltages being more than an order of magnitude different, both higher and lower, than the voltages calculated utilizing regional 1-D impedances. During the March 1989 geomagnetic storm 62 transmission lines exceed 100 V when utilizing empirical 3-D impedances, whereas 16 transmission lines exceed 100 V when utilizing regional 1-D impedances. This demonstrates the importance of using realistic impedances to understand and quantify the impact that a geomagnetic storm has on power grids.

Model Specification for Rework of Aircraft Engine, Power Transmission, and Accessory/Auxiliary Ball and Roller Bearings

Science.gov (United States)

Zaretsky, Erwin V.; Branzai, Emanuel V.

2007-01-01

This document provides a model specification for the rework and/or repair of bearings used in aircraft engines, helicopter main power train transmissions, and auxiliary bearings determined to be critical by virtue of performance, function, or availability. The rolling-element bearings to be processed under the provisions of this model specification may be used bearings removed after service, unused bearings returned from the field, or certain rejected bearings returned for reinspection and salvage. In commercial and military aircraft application, it has been a practice that rolling-element bearings removed at maintenance or overhaul be reworked and returned to service. Depending on the extent of rework and based upon theoretical analysis, representative life factors (LF) for bearings subject to rework ranged from 0.87 to 0.99 the lives of new bearings. Based on bearing endurance data, 92 percent of the bearing sets that would be subject to rework would result in L(sub 10) lives equaling and/or exceeding that predicted for new bearings. The remaining 8 percent of the bearings have the potential to achieve the analytically predicted life of new bearings when one of the rings is replaced at rework. The potential savings from bearing rework varies from 53 to 82 percent of that of new bearings depending on the cost, size, and complexity of the bearing

Optimizing transmission from distant wind farms

International Nuclear Information System (INIS)

Pattanariyankool, Sompop; Lave, Lester B.

2010-01-01

We explore the optimal size of the transmission line from distant wind farms, modeling the tradeoff between transmission cost and benefit from delivered wind power. We also examine the benefit of connecting a second wind farm, requiring additional transmission, in order to increase output smoothness. Since a wind farm has a low capacity factor, the transmission line would not be heavily loaded, on average; depending on the time profile of generation, for wind farms with capacity factor of 29-34%, profit is maximized for a line that is about 3/4 of the nameplate capacity of the wind farm. Although wind generation is inexpensive at a good site, transmitting wind power over 1600 km (about the distance from Wyoming to Los Angeles) doubles the delivered cost of power. As the price for power rises, the optimal capacity of transmission increases. Connecting wind farms lowers delivered cost when the wind farms are close, despite the high correlation of output over time. Imposing a penalty for failing to deliver minimum contracted supply leads to connecting more distant wind farms.

Grassroots Technological Resistance: The People's Power Project and the Impossible Dream of Wireless Transmission of Energy.

Science.gov (United States)

Schmidt, Pete

2017-09-01

In 1972, the Minnesota United Power Association (UPA) teamed up with the Minnesota Cooperative Power Association (CPA) to initiate an electrification project designed to bring power from North Dakota to the Twin Cities area. A significant backlash and protest began once farmers across the state became aware of the plan and the potential impending land seizure. In the midst of these actions, one group sought to create an alternative to the power line transmission system by designing a system of wireless energy transmission based on the plans of Nikola Tesla. This self-funded conglomeration of farmers and amateur researchers formed the People's Power Project (PPP) and set about building Tesla's system for the wireless transmission of energy. Using archival documents, this paper recounts this episode and argues that, in this case, the potential for successful grassroots action was derailed by the influence of longstanding myths about Tesla and his devices. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cluster-based adaptive power control protocol using Hidden Markov Model for Wireless Sensor Networks

Science.gov (United States)

Vinutha, C. B.; Nalini, N.; Nagaraja, M.

2017-06-01

This paper presents strategies for an efficient and dynamic transmission power control technique, in order to reduce packet drop and hence energy consumption of power-hungry sensor nodes operated in highly non-linear channel conditions of Wireless Sensor Networks. Besides, we also focus to prolong network lifetime and scalability by designing cluster-based network structure. Specifically we consider weight-based clustering approach wherein, minimum significant node is chosen as Cluster Head (CH) which is computed stemmed from the factors distance, remaining residual battery power and received signal strength (RSS). Further, transmission power control schemes to fit into dynamic channel conditions are meticulously implemented using Hidden Markov Model (HMM) where probability transition matrix is formulated based on the observed RSS measurements. Typically, CH estimates initial transmission power of its cluster members (CMs) from RSS using HMM and broadcast this value to its CMs for initialising their power value. Further, if CH finds that there are variations in link quality and RSS of the CMs, it again re-computes and optimises the transmission power level of the nodes using HMM to avoid packet loss due noise interference. We have demonstrated our simulation results to prove that our technique efficiently controls the power levels of sensing nodes to save significant quantity of energy for different sized network.

Development of a PLC modem for data transmission over a PWM power supply

Science.gov (United States)

Batard, Christophe; Ginot, Nicolas; Mannah, Marc Anthony; Millet, Christophe; Poitiers, Frédéric

2014-04-01

In variable-speed electrical drive and online conditioning monitoring, a feedback loop is required in order to transmit the sensor information from the motor to the controller close to the inverter. Additional cabling is used for signalling. This extra cabling has a significant cost and data transmission may not be reliable. Thus, the use of power line communication (PLC) technology to transmit data in motor drive application is quite interesting. The use of a PLC modem dedicated to the home network in a three-phase inverter-fed motor power cable does not work. Therefore, specific coupling interfaces are developed to transmit data through a pulse-width modulated power supply. Laboratory tests have shown that the couplers are operating properly. They ensure reliable data transmission in a motor drive application.

Design of a telemetry system based on wireless power transmission for physiological parameter monitoring

International Nuclear Information System (INIS)

Jia, Zhiwei; Yan, Guozheng; Zhu, Bingquan

2015-01-01

An implanted telemetry system for experimental animals with or without anaesthesia can be used to continuously monitor physiological parameters. This system is significant not only in the study of organisms but also in the evaluation of drug efficacy, artificial organs, and auxiliary devices. The system is composed of a miniature electronic capsule, a wireless power transmission module, a data-recording device, and a processing module. An electrocardiograph, a temperature sensor, and a pressure sensor are integrated in the miniature electronic capsule, in which the signals are transmitted in vitro by wireless communication after filtering, amplification, and A/D sampling. To overcome the power shortage of batteries, a wireless power transmission module based on electromagnetic induction was designed. The transmitting coil of a rectangular-section solenoid and a 3D receiving coil are proposed according to stability and safety constraints. Experiments show that at least 150 mW of power could pick up on the load in a volume of Φ10.5 mm × 11 mm, with a transmission efficiency of 2.56%. Vivisection experiments verified the feasibility of the integrated radio-telemetry system

Design of a telemetry system based on wireless power transmission for physiological parameter monitoring

Energy Technology Data Exchange (ETDEWEB)

Jia, Zhiwei, E-mail: jiayege@hotmail.com [College of Electrical and Information Engineering, Changsha University of Science and Technology, Changsha (China); Yan, Guozheng; Zhu, Bingquan [820 Institute, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China)

2015-04-15

An implanted telemetry system for experimental animals with or without anaesthesia can be used to continuously monitor physiological parameters. This system is significant not only in the study of organisms but also in the evaluation of drug efficacy, artificial organs, and auxiliary devices. The system is composed of a miniature electronic capsule, a wireless power transmission module, a data-recording device, and a processing module. An electrocardiograph, a temperature sensor, and a pressure sensor are integrated in the miniature electronic capsule, in which the signals are transmitted in vitro by wireless communication after filtering, amplification, and A/D sampling. To overcome the power shortage of batteries, a wireless power transmission module based on electromagnetic induction was designed. The transmitting coil of a rectangular-section solenoid and a 3D receiving coil are proposed according to stability and safety constraints. Experiments show that at least 150 mW of power could pick up on the load in a volume of Φ10.5 mm × 11 mm, with a transmission efficiency of 2.56%. Vivisection experiments verified the feasibility of the integrated radio-telemetry system.

One-dimensional pressure transfer models for acoustic-electric transmission channels

Science.gov (United States)

Wilt, K. R.; Lawry, T. J.; Scarton, H. A.; Saulnier, G. J.

2015-09-01

A method for modeling piezoelectric-based ultrasonic acoustic-electric power and data transmission channels is presented. These channels employ piezoelectric disk transducers to convey signals across a series of physical layers using ultrasonic waves. This model decomposes the mechanical pathway of the signal into individual ultrasonic propagation layers which are generally independent of the layer's adjacent domains. Each layer is represented by a two-by-two traveling pressure wave transfer matrix which relates the forward and reverse pressure waves on one side of the layer to the pressure waves on the opposite face, where each face is assumed to be in contact with a domain of arbitrary reference acoustic impedance. A rigorous implementation of ultrasonic beam spreading is introduced and implemented within applicable domains. Compatible pressure-wave models for piezoelectric transducers are given, which relate the electric voltage and current interface of the transducer to the pressure waves on one mechanical interface while also allowing for passive acoustic loading of the secondary mechanical interface. It is also shown that the piezoelectric model's electrical interface is compatible with transmission line parameters (ABCD-parameters), allowing for connection of electronic components and networks. The model is shown to be capable of reproducing the behavior of realistic physical channels.

A Beacon Transmission Power Control Algorithm Based on Wireless Channel Load Forecasting in VANETs.

Science.gov (United States)

Mo, Yuanfu; Yu, Dexin; Song, Jun; Zheng, Kun; Guo, Yajuan

2015-01-01

In a vehicular ad hoc network (VANET), the periodic exchange of single-hop status information broadcasts (beacon frames) produces channel loading, which causes channel congestion and induces information conflict problems. To guarantee fairness in beacon transmissions from each node and maximum network connectivity, adjustment of the beacon transmission power is an effective method for reducing and preventing channel congestion. In this study, the primary factors that influence wireless channel loading are selected to construct the KF-BCLF, which is a channel load forecasting algorithm based on a recursive Kalman filter and employs multiple regression equation. By pre-adjusting the transmission power based on the forecasted channel load, the channel load was kept within a predefined range; therefore, channel congestion was prevented. Based on this method, the CLF-BTPC, which is a transmission power control algorithm, is proposed. To verify KF-BCLF algorithm, a traffic survey method that involved the collection of floating car data along a major traffic road in Changchun City is employed. By comparing this forecast with the measured channel loads, the proposed KF-BCLF algorithm was proven to be effective. In addition, the CLF-BTPC algorithm is verified by simulating a section of eight-lane highway and a signal-controlled urban intersection. The results of the two verification process indicate that this distributed CLF-BTPC algorithm can effectively control channel load, prevent channel congestion, and enhance the stability and robustness of wireless beacon transmission in a vehicular network.

A Beacon Transmission Power Control Algorithm Based on Wireless Channel Load Forecasting in VANETs.

Directory of Open Access Journals (Sweden)

Yuanfu Mo

Full Text Available In a vehicular ad hoc network (VANET, the periodic exchange of single-hop status information broadcasts (beacon frames produces channel loading, which causes channel congestion and induces information conflict problems. To guarantee fairness in beacon transmissions from each node and maximum network connectivity, adjustment of the beacon transmission power is an effective method for reducing and preventing channel congestion. In this study, the primary factors that influence wireless channel loading are selected to construct the KF-BCLF, which is a channel load forecasting algorithm based on a recursive Kalman filter and employs multiple regression equation. By pre-adjusting the transmission power based on the forecasted channel load, the channel load was kept within a predefined range; therefore, channel congestion was prevented. Based on this method, the CLF-BTPC, which is a transmission power control algorithm, is proposed. To verify KF-BCLF algorithm, a traffic survey method that involved the collection of floating car data along a major traffic road in Changchun City is employed. By comparing this forecast with the measured channel loads, the proposed KF-BCLF algorithm was proven to be effective. In addition, the CLF-BTPC algorithm is verified by simulating a section of eight-lane highway and a signal-controlled urban intersection. The results of the two verification process indicate that this distributed CLF-BTPC algorithm can effectively control channel load, prevent channel congestion, and enhance the stability and robustness of wireless beacon transmission in a vehicular network.

Transmission pricing and stranded costs in the electric power industry

International Nuclear Information System (INIS)

Baumol, W.J.; Sidak, J.G.

1995-09-01

Stranded costs are those costs that electric utilities are currently permitted to recover through their rates but whose recovery may be impeded or prevented by the advent of competition in the industry. Estimates of these costs run from the tens to the hundreds of billions of dollars. Should regulators permit utilities to recover stranded costs while they take steps to promote competition in the electric power industry. William Baumol and J. Gregory Sidak argue that answer to that question should be yes.The authors show that a transmission price, the price for sending electricity over the transmission grid, can be determined in a manner that is compatible with economic efficiency and clearly neutral in its effects upon all competitors in electricity generation. A correctly constructed regime of transmission pricing may in fact achieve the efficiency and equity goals that justify the recovery of stranded costs

Using SMES as a multi-purpose interface in power generation, transmission and distribution systems

International Nuclear Information System (INIS)

Tam, K.S.; Zhang, X.; Yarali, A.

1991-01-01

This paper presents a new SMES schemes, the MSMES system, which significantly broadens the ways in which SMES can be applied to electric power systems. On the generation side, the SMES system can convert low-quality power into high-quality power and enhances the utilization of all energy sources available to the power systems. Acting both as an energy storage device and a power flow control device, a MSMES system can act as a hub in a power transmission system. The use of multiple MSMES systems can provide many new solutions to the problems facing the transmission networks of the United States today. On the distribution side, MSMES systems can be used as advanced power distribution centers that supply high-quality power to the customers while providing desirable load shapes to the power systems. In addition to these functions, a MSMES unit can also perform functions such as damping of power oscillation, stability and dynamic performance improvement and other recognized benefits of the conventional SMES system. Functioning as a multi-purpose power processing units, the MSMES systems improve the economics of SMES system. Functioning as a multi-purpose power processing units, the MSMES systems improve the economics of SMES technology and expand its potential market

Outage Analysis of Cooperative Transmission with Energy Harvesting Relay: Time Switching versus Power Splitting

Directory of Open Access Journals (Sweden)

Guanyao Du

2015-01-01

Full Text Available This paper investigates the multiuser transmission network with an energy harvesting (EH cooperative relay, where a source transmits independent information to multiple destinations with the help of an energy constrained relay. The relay can harvest energy from the radio frequency (RF signals transmitted from the source, and it helps the multiuser transmission only by consuming the harvested energy. By adopting the time switching and the power splitting relay receiver architectures, we firstly propose two protocols, the time switching cooperative multiuser transmission (TSCMT protocol and the power splitting cooperative multiuser transmission (PSCMT protocol, to enable the simultaneous information processing and EH at the relay for the system. To evaluate the system performance, we theoretically analyze the system outage probability for the two proposed protocols and then derive explicit expressions for each of them, respectively. Numerical results are provided to demonstrate the accuracy of our analytical results and reveal that compared with traditional noncooperative scheme our proposed protocols are green solutions to offer reliable communication and lower system outage probability without consuming additional energy. In particular, for the same transmit power at the source, the PSCMT protocol is superior to the TSCMT protocol to obtain lower system outage probability.

Comprehensive evaluation of power grid enterprises' credit rating under the reform of transmission and distribution price

Science.gov (United States)

Wang, Yongli; Wang, Gang; Zuo, Yi; Fan, Lisha; Wei, Jiaxiang

2017-03-01

On March 15, 2015, the central office issued the "Opinions on Further Deepening the Reform of Electric Power System" (in the 2015 No. 9). This policy marks the central government officially opened a new round of electricity reform. As a programmatic document under the new situation to comprehensively promote the reform of the power system, No. 9 document will be approved as a separate transmission and distribution of electricity prices, which is the first task of promoting the reform of the power system. Grid tariff reform is not only the transmission and distribution price of a separate approval, more of the grid company input-output relationship and many other aspects of deep-level adjustments. Under the background of the reform of the transmission and distribution price, the main factors affecting the input-output relationship, such as the main business, electricity pricing, and investment approval, financial accounting and so on, have changed significantly. The paper designed the comprehensive evaluation index system of power grid enterprises' credit rating under the reform of transmission and distribution price to reduce the impact of the reform on the company's international rating results and the ability to raise funds.

Calculation of voltages in electric power transmission lines during historic geomagnetic storms: An investigation using realistic earth impedances

Science.gov (United States)

Lucas, Greg M.; Love, Jeffrey J.; Kelbert, Anna

2018-01-01

Commonly, one-dimensional (1-D) Earth impedances have been used to calculate the voltages induced across electric power transmission lines during geomagnetic storms under the assumption that much of the three-dimensional structure of the Earth gets smoothed when integrating along power transmission lines. We calculate the voltage across power transmission lines in the mid-Atlantic region with both regional 1-D impedances and 64 empirical 3-D impedances obtained from a magnetotelluric survey. The use of 3-D impedances produces substantially more spatial variance in the calculated voltages, with the voltages being more than an order of magnitude different, both higher and lower, than the voltages calculated utilizing regional 1-D impedances. During the March 1989 geomagnetic storm 62 transmission lines exceed 100 V when utilizing empirical 3-D impedances, whereas 16 transmission lines exceed 100 V when utilizing regional 1-D impedances. This demonstrates the importance of using realistic impedances to understand and quantify the impact that a geomagnetic storm has on power grids.

Modeling of MEMS piezoelectric energy harvesters using electromagnetic and power system theories

KAUST Repository

Ahmad, Mahmoud Al

2012-07-23

This work proposes a novel methodology for estimating the power output of piezoelectric generators. An analytical model that estimates for the first time the loss ratio and output power of piezoelectric generators based on the direct mechanical-to-electrical analogy, electromagnetic theory, and power system theory is developed. The mechanical-to-electrical analogy and power system theory allow the derivation of an equivalent input impedance expression for the network, whereas electromagnetic transmission line theory allows deduction of the equivalent electromechanical loss of the piezoelectric generator. By knowing the mechanical input power and the loss of the network, calculation of the output power of the piezoelectric device becomes a straightforward procedure. Experimental results based on published data are also presented to validate the analytical solution. In order to fully benefit from the well-established electromagnetic transmission line and electric circuit theories, further analyses on the resonant frequency, bandwidth, and sensitivity are presented. Compared to the conventional modeling methods currently being adopted in the literature, the proposed method provides significant additional information that is crucial for enhanced device operation and quick performance optimization. © 2011 IOP Publishing Ltd.

A Modelling Approach to Multibody Dynamics of Fluid Power Machinery with Hydrodynamic Lubrication

DEFF Research Database (Denmark)

Johansen, Per; Rømer, Daniel; Andersen, Torben Ole

2013-01-01

The efficiency potential of the digital displacement technology and the increasing interest in hydraulic transmissions in wind and wave energy applications has created an incentive for development of high efficiency fluid power machinery. Modelling and analysis of fluid power machinery loss...... mechanisms is necessary in order to accommodate this demand. At present fully coupled thermo-elastic models for various tribological interfaces has been presented. However, in order to analyse the interaction between tribological interfaces in fluid power pumps and motors, these interface models needs...

Application of wireless power transmission systems in wireless capsule endoscopy: an overview.

Science.gov (United States)

Basar, Md Rubel; Ahmad, Mohd Yazed; Cho, Jongman; Ibrahim, Fatimah

2014-06-19

Wireless capsule endoscopy (WCE) is a promising technology for direct diagnosis of the entire small bowel to detect lethal diseases, including cancer and obscure gastrointestinal bleeding (OGIB). To improve the quality of diagnosis, some vital specifications of WCE such as image resolution, frame rate and working time need to be improved. Additionally, future multi-functioning robotic capsule endoscopy (RCE) units may utilize advanced features such as active system control over capsule motion, drug delivery systems, semi-surgical tools and biopsy. However, the inclusion of the above advanced features demands additional power that make conventional power source methods impractical. In this regards, wireless power transmission (WPT) system has received attention among researchers to overcome this problem. Systematic reviews on techniques of using WPT for WCE are limited, especially when involving the recent technological advancements. This paper aims to fill that gap by providing a systematic review with emphasis on the aspects related to the amount of transmitted power, the power transmission efficiency, the system stability and patient safety. It is noted that, thus far the development of WPT system for this WCE application is still in initial stage and there is room for improvements, especially involving system efficiency, stability, and the patient safety aspects.

Ultracompact Implantable Design With Integrated Wireless Power Transfer and RF Transmission Capabilities.

Science.gov (United States)

Sun, Guilin; Muneer, Badar; Li, Ying; Zhu, Qi

2018-04-01

This paper presents an ultracompact design of biomedical implantable devices with integrated wireless power transfer (WPT) and RF transmission capabilities for implantable medical applications. By reusing the spiral coil in an implantable device, both RF transmission and WPT are realized without the performance degradation of both functions in ultracompact size. The complete theory of WPT based on magnetic resonant coupling is discussed and the design methodology of an integrated structure is presented in detail, which can guide the design effectively. A system with an external power transmitter and implantable structure is fabricated to validate the proposed approach. The experimental results show that the implantable structure can receive power wirelessly at 39.86 MHz with power transfer efficiency of 47.2% and can also simultaneously radiate at 2.45 GHz with an impedance bandwidth of 10.8% and a gain of -15.71 dBi in the desired direction. Furthermore, sensitivity analyses are carried out with the help of experiment and simulation. The results reveal that the system has strong tolerance to the nonideal conditions. Additionally, the specific absorption rate distribution is evaluated in the light of strict IEEE standards. The results reveal that the implantable structure can receive up to 115 mW power from an external transmitter and radiate 6.4 dB·m of power safely.

Lightning Protection Performance Assessment of Transmission Line Based on ATP model Automatic Generation

Directory of Open Access Journals (Sweden)

Luo Hanwu

2016-01-01

Full Text Available This paper presents a novel method to solve the initial lightning breakdown current by combing ATP and MATLAB simulation software effectively, with the aims to evaluate the lightning protection performance of transmission line. Firstly, the executable ATP simulation model is generated automatically according to the required information such as power source parameters, tower parameters, overhead line parameters, grounding resistance and lightning current parameters, etc. through an interface program coded by MATLAB. Then, the data are extracted from the generated LIS files which can be obtained by executing the ATP simulation model, the occurrence of transmission lie breakdown can be determined by the relative data in LIS file. The lightning current amplitude should be reduced when the breakdown occurs, and vice the verse. Thus the initial lightning breakdown current of a transmission line with given parameters can be determined accurately by continuously changing the lightning current amplitude, which is realized by a loop computing algorithm that is coded by MATLAB software. The method proposed in this paper can generate the ATP simulation program automatically, and facilitates the lightning protection performance assessment of transmission line.

QoE-based transmission strategies for multi-user wireless information and power transfer

Directory of Open Access Journals (Sweden)

Taehun Jung

2015-12-01

Full Text Available One solution to the problem of supplying energy to wireless networks is wireless power transfer. One such technology–electromagnetic radiation enabled wireless power transfer–will change traditional wireless networks. In this paper, we investigate a transmission strategy for multi-user wireless information and power transfer. We consider a multi-user multiple-input multiple-output (MIMO channel that includes one base station (BS and two user terminals (UT consisting of one energy harvesting (EH receiver and one information decoding (ID receiver. Our system provides transmission strategies that can be executed and implemented in practical scenarios. The paper then analyzes the rate–energy (R–E pair of our strategies and compares them to those of the theoretical optimal strategy. We furthermore propose a QoE-based mode selection algorithm by mapping the R–E pair to the utility functions.

Micro-intestinal robot with wireless power transmission: design, analysis and experiment.

Science.gov (United States)

Shi, Yu; Yan, Guozheng; Chen, Wenwen; Zhu, Bingquan

2015-11-01

Video capsule endoscopy is a useful tool for noninvasive intestinal detection, but it is not capable of active movement; wireless power is an effective solution to this problem. The research in this paper consists of two parts: the mechanical structure which enables the robot to move smoothly inside the intestinal tract, and the wireless power supply which ensures efficiency. First, an intestinal robot with leg architectures was developed based on the Archimedes spiral, which mimics the movement of an inchworm. The spiral legs were capable of unfolding to an angle of approximately 155°, which guaranteed stability of clamping, consistency of surface pressure, and avoided the risk of puncturing the intestinal tract. Secondly, the necessary power to operate the robot was far beyond the capacity of button batteries, so a wireless power transmission (WPT) platform was developed. The design of the platform focused on power transfer efficiency and frequency stability. In addition, the safety of human tissue in the alternating electromagnetic field was also taken into consideration. Finally, the assembled robot was tested and verified with the use of the WPT platform. In the isolated intestine, the robot system successfully traveled along the intestine with an average speed of 23 mm per minute. The obtained videos displayed a resolution of 320 × 240 and a transmission rate of 30 frames per second. The WPT platform supplied up to 500 mW of energy to the robot, and achieved a power transfer efficiency of 12%. It has been experimentally verified that the intestinal robot is safe and effective as an endoscopy tool, for which wireless power is feasible. Proposals for further improving the robot and wireless power supply are provided later in this paper. Copyright © 2015 Elsevier Ltd. All rights reserved.

An Effective Distributed Model for Power System Transient Stability Analysis

Directory of Open Access Journals (Sweden)

MUTHU, B. M.

2011-08-01

Full Text Available The modern power systems consist of many interconnected synchronous generators having different inertia constants, connected with large transmission network and ever increasing demand for power exchange. The size of the power system grows exponentially due to increase in power demand. The data required for various power system applications have been stored in different formats in a heterogeneous environment. The power system applications themselves have been developed and deployed in different platforms and language paradigms. Interoperability between power system applications becomes a major issue because of the heterogeneous nature. The main aim of the paper is to develop a generalized distributed model for carrying out power system stability analysis. The more flexible and loosely coupled JAX-RPC model has been developed for representing transient stability analysis in large interconnected power systems. The proposed model includes Pre-Fault, During-Fault, Post-Fault and Swing Curve services which are accessible to the remote power system clients when the system is subjected to large disturbances. A generalized XML based model for data representation has also been proposed for exchanging data in order to enhance the interoperability between legacy power system applications. The performance measure, Round Trip Time (RTT is estimated for different power systems using the proposed JAX-RPC model and compared with the results obtained using traditional client-server and Java RMI models.

Model-based servo hydraulic control of a continuously variable transmission

NARCIS (Netherlands)

Cools, S.J.M.; Veenhuizen, P.A.; Pauwelussen, J.P.

2004-01-01

In order to reduce the power consumption of a transmission, maximum tracking accuracy should be achieved of both ratio and pressures in the variator. A control strategy is proposed to steer a variator, actuated with a newly developed hydraulic system, of a Continuously Variable Transmission (CVT).

Bio-Inspired Distributed Transmission Power Control Considering QoS Fairness in Wireless Body Area Sensor Networks.

Science.gov (United States)

Lee, Chan-Jae; Jung, Ji-Young; Lee, Jung-Ryun

2017-10-14

Recently, the development of wireless body area sensor network (WBASN) has accelerated due to the rapid development of wireless technology. In the WBASN environment, many WBASNs coexist where communication ranges overlap with each other, resulting in the possibility of interference. Although nodes in a WBASN typically operate at a low power level, to avoid adversely affecting the human body, high transmission rates may be required to support some applications. In addition to this, since many varieties of applications exist in the WBASN environment, each prospective user may have different quality of service (QoS) requirements. Hence, the following issues should be considered in the WBASN environment: (1) interference between adjacent WBASNs, which influences the performance of a specific system, and (2) the degree of satisfaction on the QoS of each user, i.e., the required QoS such as user throughput should be considered to ensure that all users in the network are provided with a fair QoS satisfaction. Thus, in this paper, we propose a transmission power adjustment algorithm that addresses interference problems and guarantees QoS fairness between users. First, we use a new utility function to measure the degree of the satisfaction on the QoS for each user. Then, the transmission power of each sensor node is calculated using the Cucker-Smale model, and the QoS satisfaction of each user is synchronized dispersively. The results of simulations show that the proposed algorithm performs better than existing algorithms, with respect to QoS fairness and energy efficiency.

Optimising trans-national power generation and transmission investments: a Southern African example

International Nuclear Information System (INIS)

Graeber, Bernhard; Spalding-Fecher, Randall; Gonah, Brian

2005-01-01

Increased integration and co-operation within the Southern African power sector has opened up significant opportunities for reducing the economic and environmental costs of meeting increasing electricity demand in Southern Africa. This paper applies a linear programming model to investigate the economic and environmental benefits of regional integrated planning for electricity, and the impact of including environmental costs in the decision-making process. We find that, from a financial perspective, optimising generation and transmission investments in the region would result in savings of dollar 2-4 billion over 20 years, or 5% of total system costs. Introducing a tax based on the external damage costs of carbon dioxide as part of the decision-making process would result in moderate increases in financial costs (15-20%), but would reduce regional carbon emissions by up to 55% at a mitigation cost of dollar 11 per tonne of carbon dioxide. This raises the possibility of financing regional power projects with Clean Development Mechanism funding, which we explore with an example

Transmission Power Adaption for Full-Duplex Relay-Aided Device-to-Device Communication

Directory of Open Access Journals (Sweden)