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Sample records for adjustable speed drives

  1. Adjustable Speed Drives and Power Quality

    Davari, Pooya; Yang, Yongheng; Zare, Firuz;

    2016-01-01

    This paper provides an overview and proposes cost-effective and efficient opportunities in improving power quality in Adjustable Speed Drive (ASD) systems. In particular, an Electronic Inductor (EI) technique has been used in single drives to overcome the existing challenges in conventional...

  2. Adjustable Speed Drives - Future Challenges and Applications

    Blaabjerg, Frede; Thoegersen, Paul

    2004-01-01

    The main trends within Adjustable Drives in industrial and appliance applications for the next decade are discussed based on the newest developments seen on the market and a few historical trends. Different drive configurations are presented and the general demands to adjustable speed drives are...... specified. Further on power architectures and motor types are discussed in a short term and long-term view. Possible drivers of the future development are identified, and the concept of an ?Electronic Motor? is discussed. A number of applications are presented where variable speed is attractive....

  3. Retrofitting adjustable speed drives for large induction motors

    Adjustable speed drives (ASDs) are used in many power plants to control process flow by varying the speed of synchronous and induction motors. In applications where the flow requirements vary significantly, ASDs reduce energy and maintenance requirements when compared with drag valves, dampers or other methods to control flow. Until recently, high horsepower ASDs were not available for induction motors. However, advances in power electronics technology have demonstrated the reliability and cost effectiveness of ASDs for large horsepower induction motors. Emphasis on reducing operation and maintenance costs and increasing the capacity factor of nuclear power plants has led some utilities to consider replacing flow control devices in systems powered by large induction motors with ASDs. ASDs provide a high degree of reliability and significant energy savings in situations where full flow operation is not needed for a substantial part of the time. This paper describes the basic adjustable speed drive technologies available for large induction motor applications, ASD operating experience and retrofitting ASDs to replace the existing GE Boiling Water Reactor recirculation flow control system

  4. Adjustable speed drives: Applications and R&D needs

    Stefanovic, V.R.

    1995-09-01

    The largest opportunity for the growth of adjustable speed drives (ASDs) during the next 5-6 years is in pump, fan and compressor (PFC) applications where a constant, fixed speed operation is converted to adjustable speed in order to realize energy savings. Inverter supplied induction motors are and will continue to be predominately used in these applications. Over the long term (10-15 years), the greatest ASD growth is expected in large volume consumer applications: first in hybrid electric vehicles (EVs) and in residential heating, ventilation and air-conditioning (HVAC). Both induction and a variety of AC Permanent Magnet motors are expected to be the dominant technology in this new field. The traditional ASD applications in industries which require adjustable speed (such as machine tools, robotics, steel rolling, extruders, paper mill finishing lines, etc.) offer a relatively limited potential for above average ASD growth since most of these applications have already converted to electronic speed control. As a result, ASD growth in this sector will essentially track the growth of the corresponding industries. If realized, both short and long term ASD growth opportunities will result in significant advancements of ASD technology, which will then substantially affect all other, more fragmented, ASD applications. In fact, any single large volume ASD application will serve as a catalyst for improving ASD characteristics in all other ASD applications with the same voltage rating. ASD cost and reliability (defined in the context of application compatibility) are the two most important factors which will determine whether the ASD growth opportunities are realized. Conversely, any technological improvement which carries a cost increase will be restricted to niche applications, at best. Consequently, future R & D efforts should be directed to secure reduction in ASD cost and improvement in ASD reliability. A specific action plan is outlined in this report.

  5. ANALYSIS OF EFFECTS OF VECTOR CONTROL ON TOTAL CURRENT HARMONIC DISTORTION OF ADJUSTABLE SPEED AC DRIVE

    KARTIK TAMVADA

    2012-04-01

    Full Text Available Adjustable speed drive (ASD is becoming a significant load component for power distribution. It involves the use of an Induction motor (IM. This paper involves modeling and control of an Induction motor andinvestigates its effects on the total current harmonic distortion of the adjustable speed ac drives. The simulation was carried out with the aid of the Simulink toolbox available in Matlab. It is seen that with Vector control the THDi of the drive reduces considerably.

  6. ANALYSIS OF EFFECTS OF VECTOR CONTROL ON TOTAL CURRENT HARMONIC DISTORTION OF ADJUSTABLE SPEED AC DRIVE

    KARTIK TAMVADA; R.KAMESWARA RAO

    2012-01-01

    Adjustable speed drive (ASD) is becoming a significant load component for power distribution. It involves the use of an Induction motor (IM). This paper involves modeling and control of an Induction motor andinvestigates its effects on the total current harmonic distortion of the adjustable speed ac drives. The simulation was carried out with the aid of the Simulink toolbox available in Matlab. It is seen that with Vector control the THDi of the drive reduces considerably.

  7. Minimize Adverse Motor and Adjustable Speed Drive Interactions - Motor Tip Sheet #15

    None

    2008-07-01

    Electronic adjustable speed drives (ASDs) are an extremely efficient and valuable asset to motor systems. They allow precise process control and provide energy savings within systems that do not need to continuously operate at full output.

  8. FLC based adjustable speed drives for power quality enhancement

    Sukumar Darly

    2010-01-01

    Full Text Available This study describes a new approach based on fuzzy algorithm to suppress the current harmonic contents in the output of an inverter. Inverter system using fuzzy controllers provide ride-through capability during voltage sags, reduces harmonics, improves power factor and high reliability, less electromagnetic interference noise, low common mode noise and extends output voltage range. A feasible test is implemented by building a model of three-phase impedance source inverter, which is designed and controlled on the basis of proposed considerations. It is verified from the practical point of view that these new approaches are more effective and acceptable to minimize the harmonic distortion and improves the quality of power. Due to the complex algorithm, their realization often calls for a compromise between cost and performance. The proposed optimizing strategies may be applied in variable-frequency dc-ac inverters, UPSs, and ac drives.

  9. Adjustable Speed Drive Project for Teaching a Servo Systems Course Laboratory

    Rodriguez-Resendiz, J.; Herrera-Ruiz, G.; Rivas-Araiza, E. A.

    2011-01-01

    This paper describes an adjustable speed drive for a three-phase motor, which has been implemented as a design for a servo system laboratory course in an engineering curriculum. The platform is controlled and analyzed in a LabVIEW environment and run on a PC. Theory is introduced in order to show the sensorless algorithms. These are computed by…

  10. LC Filter Design for Wide Band Gap Device Based Adjustable Speed Drives

    Vadstrup, Casper; Wang, Xiongfei; Blaabjerg, Frede

    This paper presents a simple design procedure for LC filters used in wide band gap device based adjustable speed drives. Wide band gap devices offer fast turn-on and turn-off times, thus producing high dV/dt into the motor terminals. The high dV/dt can be harmful for the motor windings and bearings...

  11. Adjustable Speed Drives in the Next Decade. Future Steps in Industry and Academia

    Thøgersen, Paul; Blaabjerg, Frede

    2004-01-01

    The main trends for the next decade within the multi-disciplinarian field of adjustable speed drives are discussed, and a number of topics are especially addressed in this paper. The topics include market development over the last decade, historical development in power converter volume and weigh......, future drive demands, power converter architecture, interfacing to the grid, motor types, and control principles. Furthermore, some of the possibilities and trends related to decentral ?intelligence? and Internet connection are discussed.......The main trends for the next decade within the multi-disciplinarian field of adjustable speed drives are discussed, and a number of topics are especially addressed in this paper. The topics include market development over the last decade, historical development in power converter volume and weight...

  12. Adjustable-Speed Single-Phase IM Drive with Reduced Number of Switches

    Chomát, Miroslav; Lipo, T. A.

    Chicago : IEEE Industry Applications Society IAS, 2001, s. 1-6. ISBN 0-7803-7114-3. [IEEE Industry Applications Conference - Annual Meeting /36./. Chicago (US), 30.09.2001-04.10.2001] R&D Projects: GA AV ČR IAB2057903 Grant ostatní: NSFA(US) 9820434 Keywords : adjustable-speed drive * single-phase induction machine Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  13. Adjustable-Speed Drive with Single-Phase Induction Machine for HVAC Applications

    Chomát, Miroslav; Lipo, T. A.

    Vancouver : University of British Columbia, 2001, s. 1-6. ISBN 0-7803-7069-4. [Power Electronics Specialists Conference PESC 2001 /32./. Vancouver (CA), 17.06.2001-22.06.2001] R&D Projects: GA MŠk ME 332 Grant ostatní: NSFA(US) 9820434 Keywords : adjustable-speed drive * single-phase induction machine Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  14. IMPROVED PERFORMANCE OF AN ADJUSTABLE SPEED DRIVES DURING VOLTAGE SAG CONDITION

    S.S.DESWAL

    2010-06-01

    Full Text Available Voltage sags normally do not cause equipment damage but can easily disrupt the operation of sensitive loads such as electronic Adjustable Speed Drives (ASD’s. Voltage sags cause a momentary decrease in DC-link voltage triggering an under voltage trip leading to nuisance tripping of adjustable speed drives (ASD’s employed in continuous-process industries which contributes to loss in revenue. A practical ride-through scheme for an adjustable speed drives based on supercapacitor during voltage sag has been presented in this paper. The supercapacitor maintains the ASD dc bus voltage under voltage sag condition. Energy storage module is connected to support the DC-link voltage during power system faults. The performance of ASD’s under normal and power system faults is first simulated in MATLab Simulink and then experimentally verified. The Data AcQuisition boards (DAQ of National Instruments along with LabVIEW software have been used torecord the observed waveforms.

  15. Commutation effect of Adjustable Speed Drives due to installation of active harmonic filters

    Asiminoaei, Lucian; Kalaschnikow, Sergej; Hansen, Steffan;

    2011-01-01

    The success of designing an industrial installation with Active Filters depends on how precise the load profile of the application is known, because this determines the amount of harmonic currents to be compensated. However, once the Active Filter is added to the installation, the harmonic currents...... may increase due to changes in the commutation behavior of diode rectifier converters. The change of natural commutation determines higher harmonics currents of the diode rectifiers and therefore higher harmonic loading of the Active Filter in the installation. This paper presents a method to estimate...... the commutation behavior of Adjustable Speed Drives when their harmonic currents are compensated by a Shunt Active Filter. The method is formulated as an analytical computation algorithm verified by simulations. Further on the method is implemented in a Harmonic Calculation Toolbox which facilitates...

  16. The Use of Active Elements to Reduce the Size and Weight of Passive Components in Adjustable Speed Drives

    Maheshwari, Ram Krishan

    shaft voltage, the common mode voltage, the conducted emissions, and the efficiency of the two systems are compared since they are major factors which affect the size of the passive components in the drives. Although the three-level inverter requires higher number of active components as compared to the......Adjustable speed drives are considered as workhorse of industry due to various applications in different kind of industries. According to a market survey, low voltage drives are most profitable in the drive industries. The drive consists of a machine and a converter, which processes grid power and...... converts into usable power for the machine. The converter consists of active and passive components. The size, weight, and volume of the drive are decided by the passive components since they typically contribute to 75% of the weight and volume of the drive. Most popular topology for the low voltage drive...

  17. Evaluation of the Ride-Through Capability of an Active-Front-End Adjustable Speed Drive under Real Grid Conditions

    Liserre, Marco; Klumpner, Christian; Blaabjerg, Frede;

    2004-01-01

    Better quality of the input currents, unity power factor and regenerative capability are not the only benefits of equipping an Adjustable Speed Drive (ASD) with an active front-end-stage. Controlling the power inflow may enable also the reduction of the dc-link energy storage, which will then lead...

  18. Analysis of cutting-edge techniques in the high voltage and high power adjustable speed drive systems

    2009-01-01

    The high voltage and high power adjustable speed drive (ASD) system is one of the most attractive fields in power electronics, and it is also a very crucial technique for energy saving and emission reduction. This paper discussed and analyzed the main cutting-edge knowledge and issues in the process of exploiting the high voltage and high power ASD system.

  19. Shunt active filter algorithms for a three phase system fed to adjustable speed drive

    Sujatha.CH; Sravanthi.Kusam; Dr. K.Chandra shek

    2011-01-01

    This paper presents the simulation of Shunt Active Power filter by using two different control schemes, Indirect current control technique and Synchronous detection technique by using ANN. These two control techniques are working under both balanced and unbalanced three phase voltage source conditions and it is feeding to aadjustable speed drive the torque speed characteristics of a motor is presented. Indirect current control technique is implemented under dynamic load condition and load bal...

  20. Limitation of Adjustable-Speed Drive Operation by Unbalanced Voltage Supply

    Chomát, Miroslav; Schreier, Luděk; Bendl, Jiří

    Piscataway : IEEE, 2008, s. 1-6. ISBN 978-1-4244-1736-0. [International Conference on Electrical Machines - ICEM 2008 /18./. Vilamoura (PT), 06.09.2008-09.09.2008] R&D Projects: GA ČR GA102/06/0215 Institutional research plan: CEZ:AV0Z20570509 Keywords : unbalanced voltage supply * DC-link voltage pulsations * variable-speed drive Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering www.apdee.org

  1. A Review of Electronic Inductor Technique for Power Factor Correction in Three-Phase Adjustable Speed Drives

    Davari, Pooya; Yang, Yongheng; Zare, Firuz;

    2016-01-01

    Electronic Inductor (EI) techniques are promising approaches for improving the grid-side current quality, and they are suitable for motor drive applications. In this paper, different EI topologies are investigated from the efficiency perspective, including the effect of employing Silicon Carbide...... (SiC) power devices. Moreover, the influence of partial loading on component sizing in Adjustable Speed Drives (ASDs) is studied. Finally the analytical loss modelling of power switches is utilized for efficiency measurement. The theoretical analyses are verified by experimental benchmarking in an ASD...

  2. Buck-Boost Control of Four Quadrant Chopper using Symmetrical Impedance Network for Adjustable Speed Drive

    Saswati Swapna Dash; Byamakesh Nayak

    2015-01-01

    This paper proposes buck-boost capabilities of four quadrant chopper for wide range speed control of DC motor drives using symmetrical impedance network called Z-source network. By controlling the shoot through duty ratio from 0 to 0.5 and non-shoot through techniques, the Z-source four quadrant choppers can produce any desired DC voltage across the DC motor. The switching patterns for both buck and boost operations are presented to achieve four modes of operation of DC motor. As a result, th...

  3. Passive wide spectrum harmonic filter for adjustable speed drives in oil and gas industry

    Al Jaafari, Khaled Ali

    Non-linear loads such as variable speed drives constitute the bulky load of oil and gas industry power systems. They are widely used in driving induction and permanent magnet motors for variable speed applications. That is because variable speed drives provide high static and dynamic performance. Moreover, they are known of their high energy efficiency and high motion quality, and high starting torque. However, these non-linear loads are main sources of current and voltage harmonics and lower the quality of electric power system. In fact, it is the six-pulse and twelve-pulse diode and thyristor rectifiers that spoil the AC power line with the dominant harmonics (5th, 7th, 11th). They provide DC voltage to the inverter of the variable speed drives. Typical problems that arise from these harmonics are Harmonic resonances', harmonic losses, interference with electronic equipment, and line voltage distortion at the Point of Common Coupling (PCC). Thus, it is necessary to find efficient, reliable, and economical harmonic filters. The passive filters have definite advantage over active filters in terms of components count, cost and reliability. Reliability and maintenance is a serious issue in drilling rigs which are located in offshore and onshore with extreme operating conditions. Passive filters are tuned to eliminate a certain frequency and therefore there is a need to equip the system with more than one passive filter to eliminate all unwanted frequencies. An alternative solution is Wide Spectrum Harmonic passive filter. The wide spectrum harmonic filters are becoming increasingly popular in these applications and found to overcome some of the limitations of conventional tuned passive filter. The most important feature of wide spectrum harmonic passive filters is that only one capacitor is required to filter a wide range of harmonics. Wide spectrum filter is essentially a low-pass filter for the harmonic at fundamental frequency. It can also be considered as a

  4. Buck-Boost Control of Four Quadrant Chopper using Symmetrical Impedance Network for Adjustable Speed Drive

    Saswati Swapna Dash

    2015-02-01

    Full Text Available This paper proposes buck-boost capabilities of four quadrant chopper for wide range speed control of DC motor drives using symmetrical impedance network called Z-source network. By controlling the shoot through duty ratio from 0 to 0.5 and non-shoot through techniques, the Z-source four quadrant choppers can produce any desired DC voltage across the DC motor. The switching patterns for both buck and boost operations are presented to achieve four modes of operation of DC motor. As a result, the proposed model will have ride through capability during voltage sags, manage during voltage swells, used in any types of DC voltage sources such as fuel cell and solar cell and improve the reliability by reducing EMI noise. Analysis and simulation results are presented to demonstrate these new findings.

  5. Adjustable-Speed Single-Phase IM Drive with Reduced Number of Switches

    Chomát, Miroslav; Lipo, T. A.

    2003-01-01

    Roč. 39, č. 3 (2003), s. 819-825. ISSN 0093-9994 R&D Projects: GA ČR GA102/02/0554 Grant ostatní: National Science Foundation(US) GA9820434 Institutional research plan: CEZ:AV0Z2057903 Keywords : AC motor drives * converters * induction motor drives Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.783, year: 2003

  6. DUAL THREE-PHASE ADJUSTABLE SPEED DRIVE WITH SYNCHRONIZED SPACE-VECTOR MODULATION

    Oleschuk V.I.; Prudeak R.; Sizov A.S.; Iaroshenco E.M.

    2008-01-01

    Split-phase symmetrical motor drive on the base of two voltage source inverters, controlled by algorithms of synchronized pulse width modulation (PWM), has been investigated. Simulation results are presented for dual three-phase power conversion systems with continuous, discontinuous and combined versions of synchronized PWM.

  7. DUAL THREE-PHASE ADJUSTABLE SPEED DRIVE WITH SYNCHRONIZED SPACE-VECTOR MODULATION

    Oleschuk V.I.

    2008-04-01

    Full Text Available Split-phase symmetrical motor drive on the base of two voltage source inverters, controlled by algorithms of synchronized pulse width modulation (PWM, has been investigated. Simulation results are presented for dual three-phase power conversion systems with continuous, discontinuous and combined versions of synchronized PWM.

  8. Feedforward Synchronised PWM for Adjustable Speed AC Drives with Different Control Modes

    Oleschuk, Valentin; Blaabjerg, Frede; Jensen, Flemming Buus

    2002-01-01

    This paper presents a novel method of direct synchronised pulswidth modulation (PWM) for three-phase voltage source inverters, feeding induction motors with different control regimes. It is based on the universal algorithm with either simplified algebraic or accurate trigonometric control functions......, with vector approached for determination of the pulse patterns, with vector approach for determination of the pulse patterns. Different control modes of the drive system with synchronised PWM, including standard scalar V/F control, and also V2/F = constant and V/F2 = constant control regimes, have been...... analysed in the paper. Simulations give the behaviour of the PWM techniques proposed. Both continuous and discontinuous schemes of synchronised PWM, applied for the corresponding control regime, have been analysed and compared....

  9. Possibilities of increased power output from existing generator plants. Feasible changes of existing generators. New technology, ASD (Adjustable Speed Drives); Muligheter for oekt effekt fra eksisterende generatoranlegg. Mulige endringer av bestaaende generatorer. Ny teknologi, ASD (Adustable Speed Drives)

    Elstroem, A.

    1996-12-31

    The present paper relates to the increase of power output from existing generator plants in Norway by new operation profiles. The paper focuses on the consequences of increasing the power turnover and production with a particular attention to the generator itself. In addition, some of the possibilities on the use of an ASD (Adjustable Speed Drives) installation are elucidated, which is a concept on regulating the number of revolutions within small limits by synchronous rotation. According to the author, the power output of generator increases between 10 to 30%

  10. Police enforcement and driving speed.

    2008-01-01

    Speed limits are violated frequently in the Netherlands. As speed is an important factor in road crashes, the surveillance of driving speeds is one of the spearheads in the policy plans of the Dutch police. Different methods of speed enforcement have proved to be effective in reducing speed and cras

  11. Motor Integrated Variable Speed Drives

    Singh, Yash Veer

    A new trend in the variable speed drives (VSDs) is to develop fully integrated systems, which lead to low-cost products with shorter design cycles. Motor Integrated design of VSDs will reduce cable length to connect drive with machine windings and installation time for end user. The electric drives...... converter losses and its size so it can fit inside the motor housing. Weight and volume of a filter inductor has to come down drastically to make it a suitable power converter for motor integrated variable speed drives. Introduction of active power electronic switches can ensure very high performance and...

  12. Adjustable drives boost nuclear plant reliability

    A new reactor recirculation control (RRC) adjustable-speed drive (ASD) and digital control system at the Washington Nuclear Plant 2 (WNP-2), Hanford, Wash., has improved plant reliability. Installed this year, the system also will lower plant maintenance costs and reduce personnel radiation doses during maintenance, since the new system has less equipment in high-radiation areas than its predecessor. Advances in power electronics have improved the reliability of adjustable-speed drives for large induction motors. Large ASDs have been used in gas, oil, and coal-fired plants since around 1984. Plants where these systems are installed have realized energy savings and operational improvements in precisely controlling process flow. They also have reduced motor maintenance by slowing the motors when full-power operation is not needed. WNP-2 is the first nuclear utility with a boiling-water reactor to change to digitally controlled reactor recirculation pumps. The new RRC system provides improved flow control and maneuverability, when operating the nuclear reactor at reduced power levels. It controls coolant flow through the reactor core to control power during normal operation. There are two pumps rated at 47,200 gallons per minute (gpm). Each is driven by a vertical, totally enclosed, air/water-cooled, three-phase induction motor. The motor is rated at 8,900 horsepower (hp) and 1,782 revolutions per minute (rpm) and is operated from a 6,600-volt, 60-hertz (Hz) electrical power supply. THe ASD and digital control system replaced a hydraulically operated flow control valve and analog control system for throttling pump output. The replacement also resulted in removing the low-frequency motor generator set used for startup and slow-speed operation. The flow control valve system required a shift from low to high frequency at minimum flow control valve position to prevent excess reactor power conditions from forming during pump shift. 6 refs., 2 figs

  13. Robust Non-Linear Direct Torque and Flux Control of Adjustable Speed Sensorless PMSM Drive Based on SVM Using a PI Predictive Controller

    F. Naceri

    2010-01-01

    Full Text Available This paper presents a new sensorless direct torque control method for voltage inverter – fed PMSM. The control methodis used a modified Direct Torque Control scheme with constant inverter switching frequency using Space Vector Modulation(DTC-SVM. The variation of stator and rotor resistance due to changes in temperature or frequency deteriorates theperformance of DTC-SVM controller by introducing errors in the estimated flux linkage and the electromagnetic torque.As a result, this approach will not be suitable for high power drives such as those used in tractions, as they require goodtorque control performance at considerably lower frequency. A novel stator resistance estimator is proposed. The estimationmethod is implemented using the Extended Kalman Filter. Finally extensive simulation results are presented to validate theproposed technique. The system is tested at different speeds and a very satisfactory performance has been achieved.

  14. Speed of adjustment: Evidence from Borsa Istanbul

    Emrah Arioglu

    2014-06-01

    Full Text Available In this study, we investigate the speed of adjustment for leverage ratios of firms listed on Borsa Istanbul, in order to investigate the prediction of the trade-off theory, regarding capital structure rebalancing. For this purpose, we estimate the speed of adjustment by using Generalized Method of Moments system estimation technique. The results of this estimation suggest the speed of adjustment as approximately 29%. This significant speed of adjustment is consistent with the prediction of trade-off theory, which suggests that firms follow target capital structures and when the firms' leverage ratios deviate from these targets; they make financial decisions with the goal of closing the gap between the previous year's leverage and target leverage of the current period.

  15. Electric motor drive unit, especially adjustment drive for vehicles

    Litterst, P.

    1980-05-29

    An electric motor drive unit, particularly an adjustment drive for vehicles with at least two parallel drive shafts is described, which is compact and saves space, and whose manufacturing costs are low compared with those of well-known drive units of this type. The drive unit contains a suitable number of magnet systems, preferably permanent magnet systems, whose pole axes are spaced and run parallel. The two pole magnet systems have diametrically opposite shell-shaped segments, to which the poles are fixed. In at least one magnet system the two segments are connected by diametrically opposite flat walls parallel to the pole axes to form a single magnetic circuit pole housing. The segments of at least one other magnet system are arranged on this pole housing so that one of these flat walls is a magnetically conducting, connecting component of the magnetic circuit of the other magnet system.

  16. Speed of Adjustment in Cointegrated Systems

    Fanelli, Luca; Paruolo, Paolo

    2007-01-01

    This paper considers the speed of adjustment to long-run equilibria, in the context of cointegrated Vector Autoregressive Processes (VAR). We discuss the definition of multivariate p-lives for any indicator of predictive ability, concentrating on cumulated interim multipliers which converge to impact factor for increasing forecasting horizon. Interim multipliers are related to autoregressive Granger-causality coefficients, structural or generalized cumulative impulse responses. We discuss the...

  17. Output filters for AC adjustable speed drives

    Blaabjerg, Frede; Hanigovszki, Norbert; Landkildehus, Jorn, Jorn

    2007-01-01

    due to bearing currents, acoustic switching noise. Depending on the specific application, the mitigation of some of these effects (or all) might be necessary. The common solution for mitigating the secondary effects at the output of PWM-VSI is the use of output filters [3],[5],[6]. Several types...... of output filters are used and this paper presents an overview of the various output filter solutions typically employed in industrial applications. The paper does not propose any new solutions and it is intended as a guide for practicing engineers and a source of information for researchers....

  18. Rotor speed estimation for indirect stator flux oriented induction motor drive based on MRAS scheme

    Youssef Agrebi; Moncef Triki; Yassine Koubaa; Mohamed Boussak

    2007-01-01

    In this paper, a conventional indirect stator flux oriented controlled (ISFOC) induction motor drive is presented. In order to eliminate the speed sensor, an adaptation algorithm for tuning the rotor speed is proposed. Based on the model reference adaptive system (MRAS) scheme, the rotor speed is tuned to obtain an exact ISFOC induction motor drive. The reference and adjustable models, developed in stationary stator reference frame, are used in the MRAS scheme to estimate induction rotor peed...

  19. Speed of Adjustment to Selected Labour Market and Tax Reforms

    Annabelle Mourougane; Lukas Vogel

    2009-01-01

    This paper examines the length of economic adjustments to selected structural reforms, drawing on simulations with dynamic general equilibrium and macro-economic neo-Keynesian models. Employment adjustment costs appear to have only a limited effect on the pace of adjustment to reforms and the influence of price adjustment costs on output dynamics is found to be marginal. Accommodative monetary policy can speed up the adjustment to a new equilibrium, though to a varying degree in the different...

  20. Electric motor drive with infinitely variable speed transmission

    Tibbals, E.C. Jr.

    1983-07-05

    A drive system adapted for use in motor vehicles comprises an infinitely variable speed drive transmission coupled to a DC motor, and the speed ratio of the transmission is controlled by a speed-responsive flyweight or governor so as to maintain the DC motor at its most efficient operating level.

  1. Speed-calming measures and their Effect on driving speed

    Agerholm, Niels; Knudsen, Daniel; Variyeswaran, Kajan

    2016-01-01

    Speeding increases the risk and severity of accidents, especially for vulnerable road users. Hence, minimisation of speeding in built-up areas is vital. Some countries widely use speed-calming measures (SCs). Documentation shows that SCs reduce speeding considerably although various types and...... designs of SCs affect this reduction. This paper includes studies of the effects from establishment of sinus speed humps of height 10 cm and length 950 cm and chicanes (with a free carriageway width of 5,30 cm and a length between the 0.5 m wide obstacles of 18 m) as a before/after study where the speed....... Despite the apparent absence of more distant effects of each SC, there is an overall reduced average speed on the full length of a road with SCs. Humps reduce the mean speed comparable to the reduction from chicanes, but the speed variation is less reduced near chicanes, and especially prior to the...

  2. Speed choice and steering behavior in curve driving

    van Winsum, W.; Godthelp, J

    1996-01-01

    The relation between speed choice and steering performance during curve negotiation was studied in a driving simulator. The hypothesis was that curve radius and steering competence both affect steering error during curve driving, resulting in compensatory speed choice. In this, the control of safety

  3. To the Problem of Electromechanical Interaction in Elevators with Controlled Electric Drive and Fuzzy Speed Controller

    A. S. Koval

    2010-01-01

    Full Text Available The paper considers problems concerning electromechanical interaction in elevators with an adjustable asynchronous electric drive equipped with the vector control systems under direct torque control and direct torque control with pulse-width modulator. A mathematical description of electromechanical elevator system with due account of nonlinearity of the worm gear is given in the paper. The paper presents a simplified circuit design of a control system with a fuzzy speed controller. It has been established that the factor of electromechanical interaction in electromechanical system with the adjustable asynchronous electric drive and an fuzzy speed controller is within the range which corresponds to existence of the essential electromechanical interaction.

  4. Robust Underestimation of Speed During Driving: A Field Study.

    Schütz, Alexander C; Billino, Jutta; Bodrogi, Peter; Polin, Dmitrij; Khanh, Tran Q; Gegenfurtner, Karl R

    2015-12-01

    Traffic reports consistently identify speeding as a substantial source of accidents. Adequate driving speeds require reliable speed estimation; however, there is still a lack of understanding how speed perception is biased during driving. Therefore, we ran three experiments measuring speed estimation under controlled driving and lighting conditions. In the first experiment, participants had to produce target speeds as drivers or had to judge driven speed as passengers. Measurements were performed at daylight and at night. In the second experiment, participants were required to produce target speeds at dusk, under rapidly changing lighting conditions. In the third experiment, we let two cars approach and pass each other. Drivers were instructed to produce target speeds as well as to judge the speed of the oncoming vehicle. Here measurements were performed at daylight and at night, with full or dipped headlights. We found that passengers underestimated driven speed by about 20% and drivers went over the instructed speed by roughly the same amount. Interestingly, the underestimation of speed extended to oncoming cars. All of these effects were independent of lighting conditions. The consistent underestimation of speed could lead to potentially fatal situations where drivers go faster than intended and judge oncoming traffic to approach slower than it actually is. PMID:26562855

  5. Rotor speed estimation for indirect stator flux oriented induction motor drive based on MRAS scheme

    Youssef Agrebi

    2007-09-01

    Full Text Available In this paper, a conventional indirect stator flux oriented controlled (ISFOC induction motor drive is presented. In order to eliminate the speed sensor, an adaptation algorithm for tuning the rotor speed is proposed. Based on the model reference adaptive system (MRAS scheme, the rotor speed is tuned to obtain an exact ISFOC induction motor drive. The reference and adjustable models, developed in stationary stator reference frame, are used in the MRAS scheme to estimate induction rotor peed from measured terminal voltages and currents. The IP gains speed controller and PI gains current controller are calculated and tuned at each sampling time according to the new estimated rotor speed. The proposed algorithm has been tested by numerical simulation, showing the capability of driving active load; and stability is preserved. Experimental results obtained with a general-purpose 1-kW induction machine are presented showing the effectiveness of the proposed approach in terms of dynamic performance.

  6. Comparing a driving simulator to the real road regarding distracted driving speed

    Knapper, A.S.; CHRISTOPH,M; Hagenzieker, M.P.; Brookhuis, K.A.

    2015-01-01

    Relative and absolute validity of a driving simulator were assessed regarding effects on mean speed and speed variation during distracting secondary tasks, and normal driving. 16 participants drove the same route four times, twice in a simulator and twice in the real world. They performed way finding tasks, using either a paper map or a route guidance system, and mobile phone conversation tasks. Furthermore, driving without secondary tasks on other road segments in the two methods was compare...

  7. Comparing a driving simulator to the real road regarding distracted driving speed.

    Knapper, A. Christoph, M. Hagenzieker, M. & Brookhuis, K.

    2015-01-01

    Relative and absolute validity of a driving simulator were assessed regarding effects on mean speed and speed variation during distracting secondary tasks, and normal driving. 16 participants drove the same route four times, twice in a simulator and twice in the real world. They performed way finding tasks, using either a paper map or a route guidance system, and mobile phone conversation tasks. Furthermore, driving without secondary tasks on other road segments in the two methods was compare...

  8. Driving simulator validation for speed research on a horizontal curve

    CORNU, Joris; Ariën, Caroline; Gardeniers, Beau; BRIJS, Kris; Daniels, Stijn; Brijs, Tom; Wets, Geert

    2016-01-01

    his paper describes the results of a validation study of the fixed-base driving simulator of the Transportation Research Institute. The main objective of this study is to investigate the usefulness of the driving simulator as a tool for speed research on a horizontal curve on a two-lane rural road. Speed was collected at seven measurement points on this horizontal curve study area in the real world. This location was rebuilt in the driving simulator environment by use of the procedure called ...

  9. Musculoskeletal analysis of driving fatigue: The influence of seat adjustments

    Majid, Noor Aliah binti Abdul; Abdullah, Mohd Fareez Edzuan; Jamaludin, Mohd Syahmi;

    2013-01-01

    Main causes for discomfort experienced by vehicle drivers during driving were investigated using a rigid-body model originally developed in the AnyBody Modeling System [1]. The interactions between the human body and the car-seat in various combinations of seat-pan/backrest inclinations...... that various seat adjustments (e.g., seat-pan and backrest inclinations) and the pedal spring stiffness have complex influences on the muscle activation and spinal joint forces of the human body. From the results, an optimal adjustment for the car-seat is proposed, i.e. the backrest inclination is 10......° and the seat-pan inclination is between 0º to 5 º. This study can in general capture the overall interactions between human body and environment (i.e. the maximum muscle activity and spine forces), which is thought to be the factors of driving fatigue....

  10. A New Low-Cost Hybrid Switched Reluctance Motor for Adjustable-Speed Pump Applications

    Lu, Kaiyuan; Rasmussen, Peter Omand; Watkins, Steve;

    2011-01-01

    This paper presents a new low-cost hybrid switched reluctance (HSR) motor intended for use in adjustable-speed pump drive systems. The motor is a single-phase motor, driven by a unipolar converter, which uses both the reluctance torque and the permanent magnet interaction torque. Compared...... with conventional single-phase switched reluctance motors, it has an increased torque density. The cogging torque is beneficially used in this motor for reducing the torque ripple. It is demonstrated that such a motor drive system can be a suitable candidate to advantageously compete with the existing motor drive...... systems for low-cost applications. Finite-element models are used to analyze and predict the motor's performance. The proposed motor drive system has been fabricated, and its performance has been tested in the laboratory. These experimental results are also presented....

  11. PERFORMANCE OF SIX PHASE PMSM DRIVE AT DIFFERENT SPEED LEVELS

    Anurag Singh Tomer; S.P.Dubey

    2016-01-01

    This paper gives a detail modelling of six phase Permanent magnet synchronous machine (PMSM) and complete simulation of  it’s drive system and performance analysis in different speed with PI controller. proposed method can be used easily in many applications like ship propulsion, Hybrid electric vehicle, Washing machine, Ship propulsion, Traction, Spinning mills, Aerospace etc. Proportional-Integral controller is mostly used in drives system. The combination of proportional and int...

  12. Speed Control of PMSM Drives by Generalized Predictive Algorithms

    Belda, Květoslav; Vošmik, D.

    Montral : IEEE Industrial Electronics Society, 2012, s. 2002-2007. ISBN 978-1-4673-2419-9. [38th Annual Conference of the IEEE Industrial Electronics Society. Montreal (CA), 25.10.2012-28.10.2012] R&D Projects: GA ČR(CZ) GAP102/11/0437 Institutional support: RVO:67985556 Keywords : Generalized Predictive Control * PMSM Drives * Speed Control Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/2012/AS/belda-speed control of pmsm drives by generalized predictive algorithms.pdf

  13. Speed Control of Bldc Motor Drive By Using Pid Controllers

    Y.Narendra Kumar,

    2014-04-01

    Full Text Available This paper mainly deals with the Brushless DC (BLDC motor speed driving systems have sprouted in various small scale and large scale applications like automobile industries, domestic appliances etc. This leads to the development in Brushless DC motor (BLDCM. The usage of BLDC Motor enhances various performance factors ranging from higher efficiency, higher torque in low-speed range, high power density ,low maintenance and less noise than other motors. The BLDC Motor can act as an alternative for traditional motors like induction and switched reluctance motors. In this paper PID controller is implemented with speed feedback loop and it is observe that torque ripples are minimized. Simulation is carried out using MATLAB / SIMULINK. The results show that the performance of BLDC Motor is quite satisfactory for various loading conditions. Brushless DC motor drives are typically employed in speed controlled applications.

  14. Speed Control of Bldc Motor Drive By Using Pid Controllers

    Y.Narendra Kumar,; P.Eswara Rao

    2014-01-01

    This paper mainly deals with the Brushless DC (BLDC) motor speed driving systems have sprouted in various small scale and large scale applications like automobile industries, domestic appliances etc. This leads to the development in Brushless DC motor (BLDCM). The usage of BLDC Motor enhances various performance factors ranging from higher efficiency, higher torque in low-speed range, high power density ,low maintenance and less noise than other motors. The BLDC Motor can act ...

  15. Improved speed estimation in sensorless PM brushless AC drives

    Shen, J. X.; Zhu, Z.Q.; Howe, D.

    2002-01-01

    The application of flux-observer-based sensorless control to permanent-magnet brushless AC motor drives is described. Current methods of speed estimation are assessed, both theoretically and experimentally, and an improved method, which combines the best features of methods in which speed is derived from the differential of rotor position and from the ratio of the electromotive force to excitation flux linkage, is proposed. Its performance is verified experimentally.

  16. Sliding Mode Speed Control for DC Drive Systems

    Guldemir, H.

    2003-01-01

    In this study, the Sliding Mode Control theory of the Variable Structure System has been applied to the speed control of a de motor. The dynamic performance of the sliding mode speed control system has been studied against system parameter variations and external load disturbance and the simulation results are given. The application of the sliding mode control theory to controller design for DC drive control system shows a robust system performance.

  17. Urban Traffic Eco-Driving: Speed Advisory Tracking

    De Nunzio, Giovanni; Canudas de Wit, Carlos; Moulin, Philippe

    2014-01-01

    International audience The evaluation of the benefits of an Eco-Driving assistance system is carried out in the urban environment in presence of traffic lights. The traffic evolution is modeled macroscopically with the Urban Variable-Length Model in a variable speed limits framework. Under the assumption of equal boundary flows, the vehicles in a road section dispose themselves according to well defined equilibrium conditions which are dependent on the traveling speed in the free-flow part...

  18. Wind generator with electronic variable-speed drives

    David, A.; Buchheit, N.; Jakobsen, H.

    1996-12-31

    Variable speed drives have been inserted between the network and the generator on certain recent wind power facilities. They have the following advantages: the drive allows the wind generator to operate at low speed with a significant reduction in acoustic noise, an important point if the facilities are sited near populated areas; the drive optimizes energy transfer, providing a gain of 4 to 10 %; the drive can possibly replace certain mechanical parts (the starting system and it in some cases, the reduction gear); the drive not only provides better transient management in relation to the network for less mechanical stress on the wind generator, it is also able to control reactive power. One commercial drive design sold by several manufacturers has already been installed on several wind generators with outputs of between 150 and 600 kw. In addition, such a solution is extremely well suited to mixed renewable energy systems. This design uses two inverse rectifier type converters and can therefore exchange energy in both directions. The equivalent drive with a single IGBT converter on the motor side and a diode converter on the network side is the solution most widely adopted throughout industry (with more than 50, 000 units installed in France per year). It still remains to be seen whether such a solution could be profitable in wind generator application (since the cost of the drive is quite high). This technical analysis is more destined for the converter-machine assembly specialists and is presented in this document, paying particular attention as it does to the modelling of the `wind energy - generator - drive - network` assembly, the associated drive command and control strategies and the simulations obtained during various transients. A 7.5 kW test bed has been installed in the Laboratoire d`Electronique de Puissance de Clamart, enabling tests to be carried out which emulate the operation of a wind generator.

  19. To the Problem of Electromechanical Interaction in Elevators with Controlled Electric Drive and Fuzzy Speed Controller

    A. S. Koval; A. V. Shvayakou

    2014-01-01

    The paper considers problems concerning electromechanical interaction in elevators with an adjustable asynchronous electric drive equipped with the vector control systems under direct torque control and direct torque control with pulse-width modulator. A mathematical description of electromechanical elevator system with due account of nonlinearity of the worm gear is given in the paper. The paper presents a simplified circuit design of a control system with a fuzzy speed controller. It has be...

  20. MODELING AND ANALYSIS OF DISTRIBUTION LOAD CURRENTS PRODUCED BY AN AD JUSTABLE SPEED DRIVE HEAT PUMP

    Hoffman, Stephen Paul

    1993-01-01

    A number of demand side management techniques have been proposed for the efficient use of electric power in the commercial and residential sector. The adjustable speed drive heat pump is a technology which has the prospect of decreasing power demands for space heating. This design has the advantage over conventional designs of higher efficiency and, potentially, reduction of peak power demand. Its main disadvantage is higher cost. Further, it has the disadvantage that it produces a load curre...

  1. Nonlinear speed control of large industrial DC motor drives with an energy efficiency enhancement loop

    Sharaf, A. M.; Masry, M. [New Brunswick Univ., Dept of Electrical and Computer Engineering, Fredericton, NB (Canada)

    1998-11-01

    MATLAB simulation of a novel dynamic speed reference trajectory tracking controller using an error driven self-adjustable, self-regulating nonlinear control block is described. Results of the digital simulation of a DC motor drive system take into account the switching inherent delay and other drive/control nonlinearities. The addition of a slow-acting dynamic motor input power tracking loop ensures power energy efficiency, minimum inrush and associated supply line harmonics, minimum load excursions and reduced energy consumption in case of a cyclical inrush type motorized load. 11 refs., 5 figs.

  2. Automated robust control system design for variable speed drives

    Okaeme, Nnamdi

    2008-01-01

    Traditional PI controllers have been largely employed for the control of industrial variable speed drives due to the design ease and performance satisfaction they provide but, the problem is that these controllers do not always provide robust performance under variable loads. Existing solutions present themselves as complex control strategies that demand specialist expertise for their implementation. As a direct consequence, these factors have limited their adoption for the industrial control...

  3. Speed estimator for induction motor drive based on synchronous speed tracking

    S B Bodkhe; M V Aware; J G Chaudhari; J G Agrawal

    2015-06-01

    This paper presents a new open-loop speed estimation method for a three-phase induction motor drive. The open-loop speed estimators available in literature have the advantage of reduced computational stress over the observers but they share a common limitation of being largely dependent on flux and machine parameters. They involve integrations and differentiation in the algorithm that leads to serious error in estimation when subject to different operating conditions. The proposed estimator is based on synchronous speed tracking and is cost-effective. It is immune to any variation in machine parameters and noise. The synchronous speed is computed from stator frequency which is estimated on-line using the stator current signals. A unique, non-adaptive method for estimation of stator frequency within one-sixteenth of time period is also proposed to enhance the speed of estimation. Computer simulation and experimentation on a 2.2 kW Field oriented controlled induction motor drive is carried out to verify the performance of proposed speed estimator. The results show excellent response over a wide range of rotor speed in both directions including low speed and under different operating conditions. This confirms the effectiveness of the proposed method.

  4. Brushless DC motor Drive during Speed regulation with Current Controller

    Bhikshalu Manchala

    2015-04-01

    Full Text Available Brushless DC Motor (BLDC is one of the best electrical drives that have increasing popularity, due to their high efficiency, reliability, good dynamic response and very low maintenance. Due to the increasing demand for compact & reliable motors and the evolution of low cost power semiconductor switches and permanent magnet (PM materials, brushless DC motors become popular in every application from home appliances to aerospace industry. The conventional techniques for controlling the stator phase current in a brushless DC drive are practically effective in low speed and cannot reduce the commutation torque ripple in high speed range. This paper presents the PI controller for speed control of BLDC motor. The output of the PI controllers is summed and is given as the input to the current controller. The BLDC motor is fed from the inverter where the rotor position and current controller is the input. The complete model of the proposed drive system is developed and simulated using MATLAB/Simulink software. The operation principle of using component is analysed and the simulation results are presented in this to verify the theoretical analysis.

  5. Design of an Ultimate High Speed Electrical Drive System

    C. Vishnu Kiran

    2014-05-01

    Full Text Available New emerging applications in the areas of portable power generation, small turbocompressors and spindles require the development of ultrahigh-speed, low power electrical drives. A 500 000 r/min, 100 W electrical drive system is presented. Because of the ultrahigh-speed requirements, standard machine design and power electronic topology choices no longer apply and the complete drive system has to be considered. A permanent magnet machine with a slotless litz-wire winding is used, which results in a low motor inductance and a high fundamental machine frequency. Three different combinations of power electronic topologies and commutation strategies have been experimentally investigated. A voltage source inverter with block commutation and an additional dc–dc converter is selected as the most optimal choice for the power electronics interface as it results in the lowest volume of the entire drive system due to lower switching losses, no heat sink cooling required, a small number of semiconductor devices, and relatively simple control implementation in a low cost digitalsignal processor.

  6. VCA Direct-Drive High Speed and Precision XY Table

    ZHAO Xingyu; FENG Xiaomei; ZHANG Dawei

    2007-01-01

    In order to compensate for the limitation of conventional XY table used in semiconductor integrated circuits(IC) packaging and improve its speed and accuracy, a voice coil actuator (VCA)direct-drive high-speed and precision positioning XY table used in wire bonder was proposed. Also, a novel flexible decoupling mechanism was used in the positioning table, and the small moving mass enabled the positioning table to move at high speed and precision. XY table deformation interference caused by assembly error and instant interference generated by dynamic load moving with high speed and acceleration can be eliminated through the flexible decoupling mechanism. Considering the positioning table as lumped mass spring system, the dynamic equations of the mechanical sys-tem and the VCA were built according to the Newton mechanics principle and electromagnetic theory. Then the electromechanical coupling control model of the system was created through Laplace transform. Based on displacement PID controller, the Icop-locked controlling algorithm of the positioning system was investigated. The dynamic control algorithm effectively improved the system dynamic performance. The precision test of the prototype machine was carried out, and the results val-idated the correctness of the model and the theory. Compared with traditional XY table, the tablehas higher speed, acceleration and positioning accuracy.

  7. Harmonic Calculation Toolbox in Industry Application for Adjustable Speed Drive

    Asiminoaei, Lucian; Blaabjerg, Frede; Hansen, Steffan

    2004-01-01

    Previous to electrical installation of large power non-linear loads, a comprehensive design-study is often required in order to determine if the overall installation complies with international regulations in respect to harmonics. Current THD voltage distortion and power factor are just few...

  8. Harmonic Calculation Software for Industrial Applications with Adjustable Speed Drives

    Asiminoaei, Lucian; Hansen, S.; Blaabjerg, Frede

    2005-01-01

    This paper describes the evaluation of a new harmonic software. By using a combination of a pre-stored database and new interpolation techniques the software can very fast provide the harmonic data on real applications. The harmonic results obtained with this software have acceptable precision even...... with limited input data. The evaluation concludes here that this approach is very practical compared to other advanced harmonic analysis methods. The results are supported by comparisons of calculations and measurements given in an industrial application....

  9. MRAS state estimator for speed sensorless ISFOC induction motor drives with Luenberger load torque estimation.

    Zorgani, Youssef Agrebi; Koubaa, Yassine; Boussak, Mohamed

    2016-03-01

    This paper presents a novel method for estimating the load torque of a sensorless indirect stator flux oriented controlled (ISFOC) induction motor drive based on the model reference adaptive system (MRAS) scheme. As a matter of fact, this method is meant to inter-connect a speed estimator with the load torque observer. For this purpose, a MRAS has been applied to estimate the rotor speed with tuned load torque in order to obtain a high performance ISFOC induction motor drive. The reference and adjustable models, developed in the stationary stator reference frame, are used in the MRAS scheme in an attempt to estimate the speed of the measured terminal voltages and currents. The load torque is estimated by means of a Luenberger observer defined throughout the mechanical equation. Every observer state matrix depends on the mechanical characteristics of the machine taking into account the vicious friction coefficient and inertia moment. Accordingly, some simulation results are presented to validate the proposed method and to highlight the influence of the variation of the inertia moment and the friction coefficient on the speed and the estimated load torque. The experimental results, concerning to the sensorless speed with a load torque estimation, are elaborated in order to validate the effectiveness of the proposed method. The complete sensorless ISFOC with load torque estimation is successfully implemented in real time using a digital signal processor board DSpace DS1104 for a laboratory 3kW induction motor. PMID:26775088

  10. Analysis of Variable Speed PFC Chopper Fed BLDC Motor Drive

    A Jeya Selvan Renius

    2015-02-01

    Full Text Available This paper provides the detailed analysis of the DC-DC chopper fed Brushless DC motor drive used for low-power applications. The various methods used to improve the power quality at the ac mains with lesser number of components are discussed. The most effective method of power quality improvement is also simulated using MATLAB Simulink. Improved method of speed control by controlling the dc link voltage of Voltage Source Inverter is also discussed with reduced switching losses. The continuous and discontinuous modes of operation of the converters are also discussed based on the improvement in power quality. The performance of the most effective solution is simulated in MATLAB Simulink environment and the obtained results are presented.

  11. Empirical Evidence of Target Leverage, Adjustment Costs and Adjustment Speed of Non-Financial Firms in Selected African Countries

    Oyebola Fatima Etudaiye-Muhtar; Rubi Ahmad

    2015-01-01

    The issue of target leverage for corporate firms in developing countries has received little attention in extant literature, especially countries in Africa. Given the imperfection that exists in African financial markets that may limit firms access to external capital, this study investigates dynamic adjustment towards a target debt ratio. In addition, the study used a dynamic panel data estimation technique to determine adjustment costs and speed of adjustment in non-financial firms in selec...

  12. From Periphery to Core: Economic Adjustments to High Speed Rail

    Ahlfeldt, Gabriel M.; Feddersen, Arne

    2010-01-01

    This paper presents evidence that high speed rail systems, by bringing economic agents closer together, sustainably promote economic activity within regions that enjoy an increase in accessibility. Our results on the one hand confirm expectations that have led to huge public investments into high speed rail all over the world. On the other hand, they confirm theoretical predictions arising from a consolidate body of (New) Economic Geography literature taking a positive, man-made and reproduci...

  13. Efficiency characteristics of speed modulated drives at predicted torque conditions for air-to-air heat pumps

    Rice, C. K.

    Examples of system (motor + inverter drive) efficiencies of two types of adjustable speed control are compared for predicted compressor and indoor blower load profiles. The two classifications are inverter-driven induction motors (IDIMs) and permanent-magnet electronically commutated motors (PM-ECMs). Reference sine-wave-driven induction motor (SWDIM) efficiencies are also given. Available bench data on late 70's IDIM compressor drives are compared to recent data on IDIM and PM-ECM drives. The drive efficiencies are compared over common operating torque requirements for heating and cooling. A modulating heat pump model was used to develop predicted reciprocating compressor torque/drive-frequency mappings and the expected operating torque ranges. The variation in modulating compressor torque requirements is analyzed. Ways to adjust the torque relation for different compressor types and sizing strategies are also discussed. Modulating blower performance data on an early '80s generation modulating heat pump with an IDIM drive (and SWDIM reference drive) were obtained and compared to bench data on recent IDIM and PM-ECM drives under similar torque conditions. In both compressor and blower applications, the combined system efficiency of the PM-ECM drives is nearly equal to or higher than that of the reference SWDIM cases and significantly better than IDIMs available in the late '70s. When compared to more recent IDIMs, the PM-ECM efficiency advantage over IDIM compressors has been reduced 40 to 50 percent between half and nominal speed (3600 rpm) but still remains 14 to 9 percent higher, respectively.

  14. Experience in the Operation of Adjustable Electric Drives of Main Circulation Pumps of BN-600 Reactors

    Adjustable electric drives of the main circulation pumps of the BN-600 reactor of the Beloyarskaya NPP have a unique layout of asynchronous valve cascades (AVC). Twenty five years of successful operation of such drives prove the expediency of the use of AVC, which deserves study and application in the design of power units with BN-800 reactors

  15. Research on Control System of Spindle Drive for High Speed Spinning Machine

    魏建

    2001-01-01

    Through analyzing the principle of spindle drive of winding mechanism for high speed spinning machine,the article not only describes a kind of mode of spindle drive for take-up motion on the basis of control method of constant velocity winding, but also introduces the design technique of software and hardware for the control system of mechatronics of spindle drive mode for take- up motion on the basis of constant velocity winding for high speed spinning machine with single-chip microcomputer. The mathematical model to describe the spindle rotating speed is established. It is an important technology for high speed spinning machine and provides a feasible application way.

  16. Intelligent speed control and effects on driving behaviour

    Horst, A.R.A. van der; Hogema, J.H.

    1999-01-01

    Supporting the driver in conducting his nowadays demanding task is a promising means to get the maximum out of the road system with respect to both efficiency and safety. With respect to safety, speed management is a main issue. Police enforcement of speeding is one approach, preventing high speeds

  17. Rotor flux and speed estimators for induction motor drives

    Blaabjerg, Frede; Teodorescu, Remus; Zelechowski, M.; Lach, P.; Rozanski, P.

    Flux and rotor speed observer is required for sensorless control of induction motor. This paper shows some different methods of estimation. There are two flux and three rotor speed estimators, which were chosen from the most promising methods presented in literature. Description of control system...

  18. Variable-speed drive and control systems for rolling mills; Atsuenkiyo drive seigyo system

    Kasai, T.; Tochigi, T. [Fuji Electric Co. Ltd., Tokyo (Japan)

    2000-11-10

    The drive systems of large rolling mills is of a cycloconverter type, a GTO (gate turn-off thyristor) type or high-voltage IGBT (insulated gate bipolar transistor) type. Drive systems for bar, rod and pipe mills use three and/or two level IGBT inverters. This paper describes recent technical trends of drives and control systems in rolling mills, including each drive application and the PLC (programmable controller) and HCI (human communication interface) controlling the total rolling mill line. (author)

  19. Internal Model Controller of an ANN Speed Sensorless Controlled Induction Motor Drives

    Hamed Mouna, Ben; Lassaad, Sbita

    This study deals with the performance analysis and implementation of a robust sensorless speed controller. The robustness is guaranteed by the use of the Internal Model Controller (IMC). An intelligent algorithm is evolved to eliminate the mechanical speed. It is based on the Artificial Neural Network (ANN) principle. Verification of the proposed robust sensorless controller is provided by experimental realistic tests on a scalar controlled induction motor drive. Sensorless robust speed control at low speeds and in field weakening region (high speeds) is studied in order to show the robustness of the speed controller under a wide range of load.

  20. Using variable speed drives technology to reap rewards of efficient HVAC design

    Electric motors are continuously running at full speed with vanes and throttles used to modulate the output, in most HVAC applications. This results in an excessive wastage of electrical energy, and the solution is the variable speed drive, which can save vast amounts of energy in fans, pumps and compressors across the HVAC system. Users of traditional control methods will not benefit from the energy savings that are possible through variable speed drives because the motor speed remains the same, with the result that some, and in some cases most, of the energy drawn will be wasted. Variable speed drives are more efficient because they control output by regulating the motor speed, rather than run the motor at full speed and use restrictions to reduce the flow. Recently, small so-called micro-drives have been launched, cutting the cost for most variable speed operation. Variable speed motors can also introduce new features to the HVAC system. An example of how drives can save money and improve the indoor climate is cited for Heathrow airport. There, the gateroom was earlier controlled by modulating valves in both heater and cooler coils, with two fans that operated continuously at rated speed. This system was very inefficient because the occupancy of the gateroom varied between zero and maximum several times daily. A new system was installed using two AC drives, in which one drive controls the supply air fan and the other the return air fan. The energy savings amounted to 89% during two tests and 77% in a third. A pump installation in the district heating system of Strasbourg, Germany, showed the savings that are possible in pump applications

  1. Self-mixing interferometry for rotational speed measurement of servo drives.

    Sun, Hui; Liu, Ji-Gou; Zhang, Quan; Kennel, Ralph

    2016-01-10

    Self-mixing interferometry (SMI) is an efficient technique applied to measure distance, velocity, displacement, and vibration. In this work, a compact and low cost SMI is applied to measure the rotational speed of a servo drive up to 6000 RPM. The application of SMI to rotational speed measurement of servo drives instead of the usage of incremental encoders is proposed. The Doppler frequency is obtained via analysis on the power spectral density, which is estimated by the smoothing periodogram method based on the fast Fourier transformation. The signals are processed in MATLAB and LABVIEW, showing that the SMI can be applied to dynamic rotational speed measurement of servo drives. Results of experiments demonstrate that this system is implementable for rotational speed measurement over the whole range from 3 RPM to 6000 RPM. In addition, the system used to measure rotational speed can also accurately record changes in position without integrating the velocity. PMID:26835757

  2. Induction generator produces constant-frequency voltage from variable-speed drive

    Riaz, M.

    1970-01-01

    Two-stage polyphase generator is usable as induction motor operable over range of speeds while powered from constant frequency source. It requires neither slip rings nor special adjustable-frequency power supplies or external reactive sources.

  3. Speed-Sensorless DTC-SVM for Matrix Converter Drives With Simple Nonlinearity Compensation

    Lee, Kyo Beum; Blaabjerg, Frede; Yoon, Tae-Woong

    2007-01-01

    This paper presents a new method to improve the sensorless performance of matrix converter drives using a parameter estimation scheme. To improve low-speed sensorless performance, the nonlinearities of a matrix converter drive such as commutation delays, turn-on and turn-off times of switching de...

  4. Speed-Sensorless DTC-SVM for Matrix Converter Drives With Simple Non-Linearity Compensation

    Lee, Kyo-Beum; Blaabjerg, Frede; Yoon, Tae-Woong

    2005-01-01

    This paper presents a new method to improve sensorless performance of matrix converter drives using a parameter estimation scheme. To improve low-speed sensorless performance, the non-Iinearities of a matrix converter drive such as commutation delays, turn-on and turn-off times of switching devic...

  5. Sensorless Speed Control including zero speed of Non Salient PM Synchronous Drives

    Rasmussen, Henrik

    2005-01-01

    including the rotor speed. Assuming motor parameters known the design achieves stability with guaranteed region of attraction even at zero speed. The control method is made robust at zero and low speed by changing the direct vector current component to a value different from zero. In order to verify the...

  6. Speed Loop Control of PMSM Driving Electric Vehicle

    Guo, Yougui; Zeng, Ping; Zhu, Jieqiong;

    2011-01-01

    Various simulation models are set up and closed speed loop control strategy of PMSM is proposed based on flux weakening control in this paper. First the model of maximum torque per ampere(MTPA) is modeled based on mathematical models and gave the corresponding simulation tests. Second the formula...

  7. Simulation Of 3-Ph To 3-Ph Cycloconverter Fed Variable Speed Drive

    Keshav B Negalur#1 , A.S.Joshikulkarni

    2013-01-01

    With harmonic distortion becoming an ever increasing concern in Variable Speed Drive (VSD) applications, virtually all Drive, manufacturers now consider limiting the generation of input current harmonics to be an important issue in their designs. This has led us to the introduction of various drives which should give us considerable reduction in the harmonic distortion. In practical application, the three-phase to threephase cycloconverter is commonly required to derive a threephase output fr...

  8. A Digital Phase Locked Loop Speed Control of Three Phase Induction Motor Drive: Performances Analysis

    Ben Hamed Mouna; Sbita Lassaâd

    2011-01-01

    This paper deals with performance analysis and implementation of a three phase inverter fed induction motor (IM) drive system. The closed loop control scheme of the drive utilizes the Digital Phase Locked Loop (DPLL). The DPLL is safely implemented all around the well known integrated circuit DPLL 4046. An ex-perimental verification is carried out on one kw scalar controlled IM system drives for a wide range of speeds and loads appliance. This presents a simple and high performance solution f...

  9. Novel wide range speed control of permanent magnet brushless motor drives

    Chau, KT; Chan, CC; Jiang, JZ; Xia, W

    1995-01-01

    This paper presents a novel approach for wide range speed control of permanent magnet (PM) brushless motor drive, including both sinewave and squarewave versions. As compared with conventional flux-weakening control, the approach takes definite advantages that it can be applied to the squarewave PM brushless motor drive directly, and even to the motor drive with negligible mutual inductances between phase windings. Moreover, it is easier to implement than flux-weakening control because no coo...

  10. An extended induction motor model for investigation of faulted machines and fault tolerant variable speed drives

    Jasim, Omar

    2010-01-01

    High performance variable speed induction motor drives have been commercially available for industrial applications for many years. More recently they have been proposed for applications such as hybrid automotive drives, and some pump applications on more electric aircraft. These applications will require the drive to operate in the presence of faults i.e. they must be “Fault Tolerant” and be capable of “Fault Ride Through”. The aim of this project was therefore to investigate fault ride thro...

  11. Brushless DC motor Drive during Speed regulation with Current Controller

    Bhikshalu Manchala; T.Amar Kiran

    2015-01-01

    Brushless DC Motor (BLDC) is one of the best electrical drives that have increasing popularity, due to their high efficiency, reliability, good dynamic response and very low maintenance. Due to the increasing demand for compact & reliable motors and the evolution of low cost power semiconductor switches and permanent magnet (PM) materials, brushless DC motors become popular in every application from home appliances to aerospace industry. The conventional techniques for controlling...

  12. A speed estimation of sensorless control for asymmetrical parameter type two-phase induction motor drives

    Nuttapong Muangchan

    2015-06-01

    Full Text Available This paper presents the concept of a speed estimation of sensorless control for asymmetrical parameter type two-phase induction motor drive, by using the adaptive observer system. The motor speed is estimated on the rotor-flux reference frame to simplicity for application. The design guideline of the gain of speed estimate system for a motor has speed change. The experimental results for all test conditions show that the responses of current, torque and speed are stable for the entire operating region.

  13. Maximum Efficiency Point Tracking for Adjustable-Speed Small Hydro Power Plant

    BORGHETTI Alberto; Di Silvestro, Mauro; Naldi, Gleb; Paolone, Mario; Alberti, Massimo

    2008-01-01

    The paper presents the general scheme and the relevant implementation of a Maximum Efficiency Point Tracking (MEPT) system for a Small Hydro Power (SHP) plant equipped with a variable-speed generator. This last consists of a Doubly Fed Induction Generator (DFIG) and a power electronic converter that independently controls both the rotor speed and the generator power factor. The MEPT is designed to be used with a propeller turbine with adjustable runner blade angle and it is coupled with the h...

  14. Measuring the impact of digital information displays on speed: a driving simulator study

    CORNU, Joris

    2012-01-01

    The primary objective of this study is to examine the impact of digital information displays on driving behavior at 70 km/h to 50 km/h transition zones. Therefore, two real world locations with a high percentage of speeding violations are rebuilt as realistic as possible in a driving simulator. Sixty-six participants completed an 18.9km trip within a randomized between (location: A, B) -within (condition: no display, smiley, 'You are speeding!', 'Speed control') subject design. Results show t...

  15. The impact of personality on driving safety among Chinese high-speed railway drivers.

    Guo, Ming; Wei, Wei; Liao, Ganli; Chu, Fulei

    2016-07-01

    This study explored the impact of personality traits on driving safety in high-speed railway drivers. A sample of high-speed railway drivers in Beijing (N=214) completed a questionnaire, including information on personality traits and background variables. The NEO Five Factor Inventory (NEO-FFI) was administered to characterize participants based on five personality traits: Neuroticism, Extraversion, Agreeableness, Openness to Experience, and Conscientiousness. The survey data were combined with naturalistic data of accident involvement and risky driving behavior in China. Poisson regression results show that drivers with high Conscientiousness and Extraversion caused fewer accidents. Higher Conscientiousness and lower Agreeableness were related to less frequent risky driving behavior. Education level and age negatively moderated the relation between certain personality traits and driving safety. The findings suggest that personality traits should be considered when selecting and training high-speed railway drivers. PMID:27035394

  16. Very-low-speed variable-structure control of sensorless induction machine drives without signal injection

    Lascu, Christian; Boldea, Ion; Blaabjerg, Frede

    2005-01-01

    A sensorless induction machine drive is presented, in which the principles of variable-structure control and direct torque control (DTC) are combined to ensure high-performance operation in the steady state and under transient conditions. The drive employs a new torque and flux controller, the...... "linear and variable-structure control", which realizes accurate and robust control in a wide speed range. Conventional DTC transient merits are preserved, while the steady-state behavior is significantly improved. The full-order state observer is a sliding-mode one, which does not require the rotor speed...... adaptation and provides accurate state estimation in the entire speed range. The proposed scheme is a complete variable-structure solution that allows persistent sensorless operation of the drive at very low speeds, including zero and 3 r/min, with full load. Simulations and extensive experimental results...

  17. Energy Efficient Control of High Speed IPMSM Drives - A Generalized PSO Approach

    GECIC, M.

    2016-02-01

    Full Text Available In this paper, a generalized particle swarm optimization (GPSO algorithm was applied to the problems of optimal control of high speed low cost interior permanent magnet motor (IPMSM drives. In order to minimize the total controllable electrical losses and to increase the efficiency, the optimum current vector references are calculated offline based on GPSO for the wide speed range and for different load conditions. The voltage and current limits of the drive system and the variation of stator inductances are all included in the optimization method. The stored optimal current vector references are used during the real time control and the proposed algorithm is compared with the conventional high speed control algorithm, which is mostly voltage limit based. The computer simulations and experimental results on 1 kW low cost high speed IPMSM drive are discussed in details.

  18. Offset Compound Gear Inline Two-Speed Drive

    Stevens, Mark A. (Inventor); Handschuh, Robert F. (Inventor); Lewicki, David G. (Inventor)

    2014-01-01

    A two-speed transmission having an input shaft and an output shaft, the transmission being capable of transitioning between fixed ratios, the high-range ratio being direct 1:1 and the low-range ratio being about 2:1. The transmission is a simple lightweight, yet robust, configuration utilizing only two gear meshes, being comprised of an input gear, a cluster gear, and an output gear. The transmission is controlled with a clutch and a sprag and with the input and output shafts turning in the same direction.

  19. Operating Regions of Adjustable-Speed Units with Doubly Fed Machines

    Schreier, Luděk; Chomát, Miroslav; Bendl, Jiří

    2004-01-01

    Roč. 49, č. 2 (2004), s. 119-136. ISSN 0001-7043 R&D Projects: GA AV ČR IAA2057102 Keywords : AC machines * adjustable-speed systems * doubly fed machine Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  20. Pipeline clean-up : speed, environment drive pipelining equipment

    Budd, G.

    2004-08-01

    Horizontal drilling technology is the single most important enhanced oil recovery technology which has resulted in a significant increase in pipeline utilization. Pipeline operators such as Calgary-based Denim Pipeline Construction Ltd. are responding by using the latest equipment, including excavation equipment, to avoid maintenance delays and downtime. The sales of Denim's horizontal pipe bending equipment have increased due to their attention to worker safety. Denim's horizontal bending machine does not require as much technical support, plus it is faster to install and speeds up production. The machine consists of 3 hydraulic jacks that move on a horizontal plate. Curved dies can be modified to accommodate various diameters of pipe. The bending operation is performed very near to the ground, thereby significantly reducing the risk of pipe injury. Environmental damage is minimized through the use of mechanized mulching which has replaced burning of unwanted trees and brush to clean for pipelines. 1 fig.

  1. Adjustable speed operation of a hydropower plant associated to an irrigation reservoir

    This paper deals with the issue of adjustable speed operation (ASO) of hydropower plants. The main idea of this technique is to allow the turbine speed to change in accordance with hydraulic conditions, thus improving the overall unit efficiency. General technical aspects of ASO are further discussed with special emphasis on the energy and operational benefits that may potentially result from its application. In order to assess these benefits, annual operation of a hydropower plant associated to an irrigation reservoir has been simulated under different scenarios, with both adjustable and fixed speed. Turbine operating range proved to be wider with ASO. In addition, simulation results confirm that considerable energy gains are expected to be obtained

  2. Prediction of Driving Ability with Neuropsychological Tests: Demographic Adjustments Diminish Accuracy

    Barrash, Joseph; Stillman, Ashley; Anderson, Steven W; UC, Ergun Y; Dawson, Jeffrey D.; Rizzo, Matthew

    2010-01-01

    Demographically-adjusted norms are used to enhance accuracy of inferences based on neuropsychological assessment. However, we hypothesized that predictive accuracy regarding complex real-world activities is diminished by demographic corrections. Driving performance was assessed with a standardized on-road test in participants aged 65+ (24 healthy elderly, 26 Alzheimer’s disease, 33 Parkinson’s disease). Neuropsychological measures included Trailmaking A and B, Complex Figure, Benton Visual Re...

  3. Intraday Speed of Adjustment and the Realized Variance in the Indonesia Stock Exchange

    Zaafri A Husodo

    2009-01-01

    Full Text Available We examine the intraday trading and price dynamics for frequently traded stocks at the Indonesian Stock Exchange. Using trade price, time series generated at one, two, three, five, ten, fifteen, thirty and sixty-minute intervals, we estimate the speed of adjustment and the corresponding realized variance of these series. The objective of the estimation is to infer the noise impact to the deviation of observed prices from their fundamental value. The result from the speed of adjustment estimate is consistent with the realized variance estimator. Both conclude that the 50 most frequently traded stocks in the Indonesia Stock Exchange adjust to new information within 30 minutes. At the interval, the coefficient of the speed of price adjustment is insignificantly different from zero implying negligible noise impact to the observed price. Concurrently, the realized variance starts to stabilize at 30-minute interval purporting fading impact of noise to the realized variance estimate. The evidence justifies the use of realized variance at various intervals as a reliable indicator of price discovery rate in the Indonesia Stock Exchange.

  4. Two wheel speed robust sliding mode control for electric vehicle drive

    Abdelfatah Nasri

    2008-01-01

    Full Text Available Nowadays the uses of electrical power resources are integrated in the modern vehicle motion traction chain so new technologies allow the development of electric vehicles (EV by means of static converters-related electric motors. All mechanical transmission devices are eliminated and vehicle wheel motion can be controlled by means of power electronics. The proposed propulsing system consists of two induction motors (IM that ensure the drive of the two back driving wheels. The proposed control structure-called independent machines- for speed control permit the achievement of an electronic differential. The electronic differential system ensures the robust control of the vehicle behavior on the road. It also allows controlling independently, every driving wheel to turn at different speeds in any curve. This paper presents the study and the sliding mode control strategy of the electric vehicle driving wheels.

  5. Simplified Fuzzy Control for Flux-Weakening Speed Control of IPMSM Drive

    M. J. Hossain

    2011-01-01

    Full Text Available This paper presents a simplified fuzzy logic-based speed control scheme of an interior permanent magnet synchronous motor (IPMSM above the base speed using a flux-weakening method. In this work, nonlinear expressions of d-axis and q-axis currents of the IPMSM have been derived and subsequently incorporated in the control algorithm for the practical purpose in order to implement fuzzy-based flux-weakening strategy to operate the motor above the base speed. The fundamentals of fuzzy logic algorithms as related to motor control applications are also illustrated. A simplified fuzzy speed controller (FLC for the IPMSM drive has been designed and incorporated in the drive system to maintain high performance standards. The efficacy of the proposed simplified FLC-based IPMSM drive is verified by simulation at various dynamic operating conditions. The simplified FLC is found to be robust and efficient. Laboratory test results of proportional integral (PI controller-based IPMSM drive have been compared with the simulated results of fuzzy controller-based flux-weakening IPMSM drive system.

  6. Modeling and Analysis of PI Controller Based Speed Control of Brushless DC Motor Drive.

    Mr.P.Nagasekhar Reddy

    2013-09-01

    Full Text Available The Brushless DC motors (BLDC find widespread applications in domestic and industries due to their low and high power density and ease of speed control. To accomplish desired level of performance the motor requires suitable speed controllers. In case of permanent magnet Brushless DC motors, usually control of speed is reached by using proportional integral (PI controller. Although the conventional PI controllers are widely used in the industry due to their simple control structure and ease of implementation, these controllers pose difficulties where there are some control complexity such as nonlinearity, load disturbances and parametric variations. Moreover PI controllers require precise linear mathematical models. In this paper, the analysis and mathematical modeling of BLDC motor is implemented. Also, speed control of three phase BLDC motor drive using power electronic device is projected by using matlab/Simulink. The simulation result shows the improved performance of developed Brushless DC motor drive.

  7. Determination of the energy performance of the pumping unit with adjustable electric drive

    Соколовський, Олег Феліксович

    2015-01-01

    Consumption power by pumping unit with adjustable electric is determined by the chosen algorithm and network control. This requires careful analysis of phenomenon of cell loss in power channel. To determine the energy losses in asynchronous motors must know the variation of motor current during transient or analytical expression change of speed over time and reliable data stator winding in case of change of temperature. Energy losses in the pump may determined by the data input and output. No...

  8. Design and static performance of high speed machining centre with "direct drive"

    Shuhong XIAO; Yulian CHEN; Guangyuan ZHENG

    2009-01-01

    "Direct drive" is an ideal method for speeding machine tools. In the structure of a CNC machining centre with "direct drive", the linear motor's primary and secondary parts are assembled into the worktable and machine bed respectively to directly drive the worktable. The built-in rotary motor is assembled in the spindle to realize the main transmission system of the machine tool "direct drive". All mechanical transmission elements in machine tools are eliminated. High speed, efficiency, and accuracy are easily obtained. However, in this type of "direct drive" machining centre, the magnetic attraction force between the primary and the secondary linear motors and the dynamic impact at acceleration and deceleration are directly imposed on the machine tool, and influence the performance of the machining centre. This paper analyzes the special demands of "direct drive" on the machine centre, and introduces a new structure of the machining tool. The worktable and machine bed are optimized to meet the special demands of "direct drive". Static performance simulation on the machining centre is done to reveal an ideal result.

  9. Speed-accuracy trade-off behavior: Response caution adjustment or mixing task strategies?

    van Maanen

    2015-01-01

    The speed-accuracy trade-off (SAT) effect refers to the behavioral trade-off between fast yet error-prone responses and accurate but slow responses. Multiple theories on the cognitive mechanisms behind SAT exist. One theory assumes that SAT is a consequence of strategically adjusting the amount of evidence required for overt behaviors, such as perceptual choices. Another theory hypothesizes that SAT is the consequence of mixing different task strategies. In this paper these theories are disam...

  10. Novel Position and Speed Estimator for PM Single Phase Brushless D.C. Motor Drives

    Lepure, Liviu I.; Andreescu, Gheorghe-Daniel; Iles, Doris;

    2010-01-01

    A novel position and speed estimator for single phase permanent magnet brushless d.c. (PMBLDC) motor drives, based on flux integration and prior knowledge of ΨPM (θ) is proposed here and an adequate correction algorithm is adopted in order to increase the robustness to noise and to reduce the...... sensitivity to accuracy of flux linkage estimation. A speed and current close loop control is employed based on the Hall signal and the motor is controlled at different speeds in order to validate the proposed estimation algorithm with satisfying results. The position correction effect is analyzed by...

  11. Senserless Speed and Position of Direct Field Orientation Control Induction Motor Drive

    Mohammed Khalil Hussain

    2012-01-01

    Full Text Available Direct field-orientation Control (DFOC of induction motor drives without mechanical speed sensors at the motor shaft has the attractions of low cost and high reliability. To replace the sensor, information on the rotor speed and position are extracted from measured stator currents and from voltages at motor terminals. In this paper presents direct field-orientation control (DFOC with two type of kalman filter (complete order and reduced order extended kalman filter to estimate flux, speed, torque and position. Simulated results show how good performance for reduced order extended kalman filter over that of complete order extended kalman filter in tracking performance and reduced time of state estimation.

  12. Speed regulated drives save energy and operating cost; Drehzahlvariable Antriebe senken Energie- und Betriebskosten

    Possberg, Norbert

    2009-12-15

    The cement factory of the Lafarge group at Hope, United Kingdom, retrofitted the last two drive units of the production chain by an electronic speed regulation. By utilization of frequency converters in the cooler ventilation sector the total energy consumption lowered to more than 15 %. (orig./GL)

  13. Comparative Study of Fuzzy Logic Based Speed Control of Multilevel Inverter fed Brushless DC Motor Drive

    Pritha Agrawal

    2014-02-01

    Full Text Available This paper presents a comparative analysis of speed control of brushless DC motor (BLDC drive fed with conventional two-level, three and five level diode clamped multilevel inverter (DC-MLI. The performance of the drive system is successfully evaluated using Fuzzy Logic (FL based speed controller. The control structure of the proposed drive system is described. The speed and torque characteristic of conventional two-level inverter is compared with the three and five-level multilevel inverter (MLI for various operating conditions. The three and five level diode clamped multilevel inverters are simulated using IGBT’s and the mathematical model of BLDC motor has been developed in MATLAB/SIMULINK environment. The simulation results show that the Fuzzy based speed controller eliminate torque ripples and provides fast speed response. The developed Fuzzy Logic model has the ability to learn instantaneously and adapt its own controller parameters based on disturbances with minimum steady state error, overshoot and rise time of the output voltage.

  14. The Digital PI Control for Driving Constant Speed of Brushless DC Motor

    Yoon, Shin Yong; Kim, Yong; Baek, Soo Hyun [Dongguk University (Korea); Kim, Hyun Soo [Chang Hung Telecom Co., Ltd. (Korea); Kim, Il Nam [Dongseoul College (Korea)

    2000-06-01

    This paper presents the improvement for speed characteristics of a Brushless DC Motor (BLDCM), it was applied to digital PI control for this. The practical PID control has been widely used to velocity control of DC motor. In this paper, a digital PI controller is used in order to decrease to speed error in constant velocity control of BLDCM. A TMS320C31 DSP is used for the microprocessor of digital PI control. The method using the DSP carry out the real-time control. The DSP has the rapid calculation ability and sampling time used 1ms. Driving BLDCM used 50W, motor input DC 150V and rotation speed 3000rpm. When BLDCM is to approval for discretion velocity at the acceleration and deceleration driving with any load, it was a feasible for stabilization control. Therefore, the experimental results indicate the superiority and validity of the velocity control by digital PI control. (author). 7 refs., 15 figs., 2 tabs.

  15. Closed Loop Speed Control of a BLDC Motor Drive Using Adaptive Fuzzy Tuned PI Controller

    Sri Latha Eti

    2014-11-01

    Full Text Available Brushless DC Motors are widely used for many industrial applications because of their high efficiency, high torque and low volume. This paper proposed an improved Adaptive Fuzzy PI controller to control the speed of BLDC motor. This paper provides an overview of different tuning methods of PID Controller applied to control the speed of the transfer function model of the BLDC motor drive and then to the mathematical model of the BLDC motor drive. It is difficult to tune the parameters and get satisfied control characteristics by using normal conventional PI controller. The experimental results verify that Adaptive Fuzzy PI controller has better control performance than the conventional PI controller. The modeling, control and simulation of the BLDC motor have been done using the MATLAB/SIMULINK software. Also, the dynamic characteristics of the BLDC motor (i.e. speed and torque as well as currents and voltages of the inverter components are observed by using the developed model.

  16. How Much Degrees Of Temperature A Warp Drive Achieves When At Superluminal Speeds?? The Analysis Of Gonzalez-Diaz Applied To The Natario Warp Drive Spacetime

    Loup, Fernando

    2013-01-01

    Warp Drives are solutions of the Einstein Field Equations that allows superluminal travel within the framework of General Relativity.There are at the present moment two known solutions: The Alcubierre warp drive discovered in $1994$ and the Natario warp drive discovered in $2001$.The warp drive seems to be very attractive because allows interstellar space travel at arbitrarily large speeds avoiding the time dilatation and mass increase paradoxes of Special Relativity. However it suffers from ...

  17. ANALYSIS OF VARIABLE SPEED PFC BUCK–BOOST CONVERTER-FED PMBLDC MOTOR DRIVE

    K. Raghavareddy

    2015-09-01

    Full Text Available This paper presents an analysis of variable speed low power drive with PFC at supply ends by using BLDC PM motor fed from buck-boost converter. The speed control of BLDC achieved by simply control the DC link voltage of VSI converter which is taken as reference signal. This facilitates the operation of VSI at fundamental frequency switching by using the electronic commutation of the BLDC motor which offers reduced switching losses. A PFC buck–boost converter is designed to operate in discontinuous inductor current mode (DICM to provide an inherent PFC at ac mains. The performance of the proposed drive is evaluated over a wide range of speed control and varying supply voltages (universal ac mains at 170–270 V with improved power quality at ac mains. The obtained power quality indices are within the acceptable limits of international power quality standards such as the IEC 61000-3-2. The performance of the proposed drive is simulated in MATLAB/Simulink environment, and the obtained results are validated experimentally on a developed prototype of the drive.

  18. Wavelet transform with fuzzy tuning based indirect field oriented speed control of three-phase induction motor drive

    Sanjeevikumar, P.; Daya, J.L. Febin; Wheeler, Patrick;

    2015-01-01

    This manuscript presents the details about the novel controller using wavelet transform and fuzzy logic tuning for speed control of an induction motor drive. The conventional proportional-integral (PI) speed controller in an indirect vector control of induction motor drive has been replaced by th...

  19. Field Oriented Control for Rotor Position Estimation of IPM Drives over a Wide Speed Range

    Ekhlas Kadhum

    2013-01-01

    Full Text Available Field oriented control strategy of Interior Permanent Magnet IPM Synchronous Motor drives over a wide speed range applications is presented. Rotor position estimation using model reference adaptive system method for IPM Drive without using a mechanical sensor is illustrated considering the effects of cross-saturation between the d and q axes. The cross saturation between d and q axes has been calculated by finite-element analysis. The inductance measurement regards the cross saturation which is used to obtain the suitable id - characteristics in base and flux weakening regions. The simulation results show that rotor position estimation error accuracy was improved. Various dynamic conditions have been investigated

  20. Investigation of Road Enviroment Effects on Choice of Urban and Interurban Driving Speed

    Ádám Török

    2011-03-01

    Full Text Available Human factor plays the most determinant role in traffic accidents. Speeding is a dominant cause of accidents in road transport. However, in order to improve safety, this is not the only element of the road transport system that should be considered. The road and/ or environment influence that behaviour as well, but they can be modified more quickly than drivers’ behaviour, and their effect can also be demonstrated. This paper describes the effect of road environment on chosen driving speed. Decisions of drivers are influenced by environmental impacts. Some of these impacts are planned, deliberate stimuli, being a part of the telematic systems of traffic control. In this paper the measure of road vehicles speed was analyzed on certain road urban and interurban sections which can be characterized by different design speed and construction parameters. Methods of mathematical statistics have been used to prove the hypothesis; the driving speed chosen by the driver depends heavily on the characteristics of urban and interurban road section. The aim of the author is to prove this hypothesis and the difference between urban and interurban decision environment.

  1. A Study of Hydrogen Generation with Doubly-Fed Adjustable Speed Wind Generator

    Kinoshita, Hirotaka; Takahashi, Rion; Murata, Toshiaki; Tamura, Junji; Sugimasa, Masatoshi; Komura, Akiyoshi; Futami, Motoo; Ichinose, Masaya; Ide, Kazumasa

    This paper presents a combination system of wind power generator and hydrogen generator. In the proposed system, Doubly-Fed Synchronous Generator (DFSG) is used as an adjustable speed wind generator, and an electrolyzer is connected to its terminal for hydrogen generation, which is controlled by power electronic converters. Output power from the wind generator is smoothed and supplied to the power system as well as to the electrolyzer to generate hydrogen under a cooperative control of the wind generator and the electrolyzer. The performance of the proposed system is investigated by simulation analyses, in which simulations are performed by using PSCAD/EMTDC.

  2. A high speed camera with auto adjustable ROI for product's outline dimension measurement

    Wang, Qian; Wei, Ping; Ke, Jun; Gao, Jingjing

    2014-11-01

    Currently most domestic factories still manually detect machine arbors to decide if they meet industry standards. This method is costly, low efficient, and easy to misjudge the qualified arbors or miss the unqualified ones, thus seriously affects factories' efficiency and credibility. In this paper, we design a specific high-speed camera system with auto adjustable ROI for machine arbor's outline dimension measurement. The entire system includes an illumination part, a camera part, a mechanic structure part and a signal processing part based on FPGA. The system will help factories to realize automatic arbor measurement, and improve their efficiency and reduce their cost.

  3. An Approach to Synthesis of a Class of Electric Drives with Dual-Zone Speed Control

    GEORGIEV, T.

    2010-11-01

    Full Text Available An approach to dual-zone speed control of DC motor electric drives is presented in this paper. The new point is that in the syntheses of controllers a combination between setting of closed-loop system poles (modal control and optimal control through the quadratic quality criterion minimization is applied. Optimal modal control is achieved whereat a new type of complex criterion for selection of the functional is used. This approach allows taking into consideration the controlled object parameters' change at determination of the optimal modal controller coefficients when speed is regulated above the rated value. The research carried out as well as the results obtained can be used in the design, optimization and tuning of such types of drive systems.

  4. Performance Indices Based Optimal Tunning Criterion for Speed Control of DC Drives Using GA

    Deepti Singh

    2014-12-01

    Full Text Available This paper presents a framework to carry out a simulation to tune the speed controller gains for known input of DC drive system. The objective is to find the optimal controller gains (proportional and integral in a closed loop system. Various performance indices have been considered as optimal criterion in this work. The optimal gain values have been obtained by conventional and Genetic Algorithm (GA based optimization methods. The study has been conducted on a simulink model of three phase converter controlled direct current (DC drive with current and speed control strategy. The results show that the GA based tunning provided better solutions as compared to conventional optimization methods based tunning.

  5. Variable Speed Wind Turbine Based on Multiple Generators Drive-Train Configuration

    Deng, Fujin; Chen, Zhe

    2010-01-01

    A variable speed wind turbine is presented in this paper, where multiple permanent magnet synchronous generators (MPMSGs) drive-train configuration is employed in the wind turbine. A cascaded multilevel converter interface based on the MPMSGs is developed to synthesize a desired high ac sinusoidal...... reduce the fluctuation of the electromagnetic torque sum and results in a good performance for the MPMSGs structure. The simulation study is conducted using PSCAD/EMTDC, and the results verify the feasibility of this variable speed wind turbine based on multiple generators drive-train configuration....... output voltage, which could be directly connected to the grids. What is more, such arrangement has been made so that the output ac voltage having a selected phase angle difference among the stator windings of multiple generators. A phase angle shift strategy is proposed in this paper, which effectively...

  6. High-speed low-power voltage-programmed driving scheme for AMOLED displays

    A new voltage-programmed driving scheme named the mixed parallel addressing scheme is presented for AMOLED displays, in which one compensation interval can be divided into the first compensation frame and the consequent N −1 post-compensation frames without periods of initialization and threshold voltage detection. The proposed driving scheme has the advantages of both high speed and low driving power due to the mixture of the pipeline technology and the threshold voltage one-time detection technology. Corresponding to the proposed driving scheme, we also propose a new voltage-programmed compensation pixel circuit, which consists of five TFTs and two capacitors (5T2C). In–Zn–O thin-film transistors (IZO TFTs) are used to build the proposed 5T2C pixel circuit. It is shown that the non-uniformity of the proposed pixel circuit is considerably reduced compared with that of the conventional 2T1C pixel circuit. The number of frames (N) preserved in the proposed driving scheme are measured and can be up to 35 with the variation of the OLED current remaining in an acceptable range. Moreover, the proposed voltage-programmed driving scheme can be more valuable for an AMOLED display with high resolution, and may also be applied to other compensation pixel circuits. (paper)

  7. Development of Permanent Magnet Reluctance Motor Suitable for Variable-Speed Drive for Electric Vehicle

    Sakai, Kazuto; Takahashi, Norio; Shimomura, Eiji; Arata, Masanobu; Nakazawa, Yousuke; Tajima, Toshinobu

    Regarding environmental and energy issues, increasing importance has been placed on energy saving in various systems. To save energy, it would be desirable if the total efficiency of various types of equipment were increased.Recently, a hybrid electric vehicle (HEV) and an electric vehicle (EV) have been developed. The use of new technologies will eventually lead to the realization of the new- generation vehicle with high efficiency. One new technology is the variable-speed drive over a wide range of speeds. The motor driving systems of the EV or the HEV must operate in the variable-speed range of up to 1:5. This has created the need for a high-efficiency motor that is capable of operation over a wide speed range. In this paper, we describe the concept of a novel permanent magnet reluctance motor (PRM) and discuss its characteristics. We developed the PRM, which has the capability of operating over a wide speed range with high efficiency. The PRM has a rotor with a salient pole, which generates magnetic anisotropy. In addition, the permanent magnets embedded in the rotor core counter the q-axis flux by the armature reaction. Then, the power density and the power factor increase. The PRM produces reluctance torque and torque by permanent magnet (PM) flux. The reluctance torque is 1 to 2 times larger than the PM torque. When the PRM operates over a constant-power speed range, the field component of the current will be regulated to maintain a constant voltage. The output power of the developed PRM is 8 to 250kW. It is clarified that the PRM operates at a wide variable-speed range (1:5) with high efficiency (92-97%). It is concluded that the PRM has high performance over a wide constant-power speed range. In addition, the PRM is constructed using a small PM, so that we can solve the problem of cost. Thus, the PRM is a superior machine that is suited for variable-speed drive applications.

  8. Optimal motion planning with the half-car dynamical model for autonomous high-speed driving

    Jeon, Jeong hwan; Cowlagi, Raghvendra V.; Peters, Steven C.; Karaman, Sertac; Frazzoli, Emilio; Tsiotras, Panagiotis; Iagnemma, Karl

    2013-01-01

    We discuss an implementation of the RRT* optimal motion planning algorithm for the half-car dynamical model to enable autonomous high-speed driving. To develop fast solutions of the associated local steering problem, we observe that the motion of a special point (namely, the front center of oscillation) can be modeled as a double integrator augmented with fictitious inputs. We first map the constraints on tire friction forces to constraints on these augmented inputs, which provides instantane...

  9. The universal quantum driving force to speed up a quantum computation -- The unitary quantum dynamics

    Miao, Xijia

    2011-01-01

    It is shown in the paper that the unitary quantum dynamics in quantum mechanics is the universal quantum driving force to speed up a quantum computation. This assertion supports strongly in theory that the unitary quantum dynamics is the fundamental and universal principle in nature. On the other hand, the symmetric structure of Hilbert space of a composite quantum system is the quantum-computing resource that is not owned by classical computation. A new quantum-computing speedup theory is se...

  10. Data-based Speed-limit-respecting Eco-driving System

    Suzdaleva, Evgenia; Nagy, Ivan

    2014-01-01

    Roč. 44, č. 1 (2014), s. 253-264. ISSN 0968-090X R&D Projects: GA TA ČR TA01030123 Institutional support: RVO:67985556 Keywords : eco-driving * fuel consumption * recommended speed * recursive estimation * quadratic optimal control * dynamic programming Subject RIV: BC - Control Systems Theory Impact factor: 2.818, year: 2014 http://library.utia.cas.cz/separaty/2014/AS/suzdaleva-0427942.pdf

  11. Variable Speed Wind Turbine Based on Multiple Generators Drive-Train Configuration

    Deng, Fujin; Chen, Zhe

    2010-01-01

    A variable speed wind turbine is presented in this paper, where multiple permanent magnet synchronous generators (MPMSGs) drive-train configuration is employed in the wind turbine. A cascaded multilevel converter interface based on the MPMSGs is developed to synthesize a desired high ac sinusoidal output voltage, which could be directly connected to the grids. What is more, such arrangement has been made so that the output ac voltage having a selected phase angle difference among the stator w...

  12. Energy efficiency high speed drives with magnetic bearings; Energieeffizienz durch schnell drehende, magnetgelagerte Antriebe

    Kroll, Matthias [LEViTEC GmbH, Lahnau (Germany)

    2011-07-01

    In modern purification plans the contamination of the wastewater are biologically removed by supplying oxygen. The clarifier is ventilated by compressors around the clock and approximately 60% of the total energy consumption is used for that. It enables a great opportunity for saving energy. This contribution shows that the use of magnetic centrifugal compressors with high-speed drives leads to significant reduction of energy consumption. In addition, the drive is, due to contact free the magnetic bearings, practically wear- and maintenance-free. By the use of integrated sensors in the magnetic bearings a continuous monitoring of the compressor is implemented. Consequently this drive concept provides not only more efficiency and less energy consumption, but also leads to a higher plant availability. (orig.)

  13. Feed drive simulation for the prediction of the tool path follow up in High Speed Machining

    Prévost, David; Lartigue, Claire

    2010-01-01

    This paper deals with an advanced modeling of the feed drives of a five axis machine tool within the context of High Speed Machining. The management of the multi axes as well as high velocities causes problems to the set machine tool - Numerical Controller throughout the trajectory execution process. As a result, many errors are introduced during machining all process long affecting the surface quality. The paper aims at modeling the feed drive dynamics during trajectory follow-up including the current, the velocity and position loops as well as the feed forward terms, which characterize classical drives on actual HSM machines. It concerns translational axes as well as rotary axes. A procedure of identification is implemented. Performances of the model are assessed by the comparison between simulated tool paths to the real one. Experimental verifications of the virtual axis model are detailed for three and five axis trajectories presenting various types of geometrical discontinuities.

  14. Combinatorial Optimization Method for Operation of Pumping Station with Adjustable Blade and Variable Speed Based on Experimental Optimization of Subsystem

    Yi Gong; Jilin Cheng

    2014-01-01

    A decomposition-dynamic programming aggregation method based on experimental optimization for subsystem was proposed to solve mathematical model of optimal operation for single pumping station with adjustable blade and variable speed. Taking minimal daily electric cost as objective function and water quantity pumped by units as coordinated variable, this model was decomposed into several submodels of daily optimal operation with adjustable blade and variable speed for single pump unit which w...

  15. Optimizing the driving scheme of a self-actuated atomic force microscope probe for high-speed applications

    We investigate the optimum driving scheme of a dynamic atomic force microscope with a self-actuated probe for high-speed applications by performing numerical simulations. We compare the recently developed methods such as Q-control, dynamic PID control, and modified Q-control methods to the standard tapping mode by considering scan speed and peak transient forces. In addition, the effects of driving frequency and set-point amplitude on the maximum achievable scan speed for the same probe-sample system are discussed. We find that the scan speed can be increased significantly at the expense of increased peak transient forces. -- Highlights: → Driving schemes of a dynamic AFM are examined to achieve the highest scan speed. → Q-control provides the highest scan speed with increased transient forces. → Off-resonance tapping is preferable unless transient forces can be ignored. → False error signal generation methods provide a slight improvement.

  16. High-speed low-power voltage-programmed driving scheme for AMOLED displays

    Xingheng, Xia; Weijing, Wu; Xiaofeng, Song; Guanming, Li; Lei, Zhou; Lirong, Zhang; Miao, Xu; Lei, Wang; Junbiao, Peng

    2015-12-01

    A new voltage-programmed driving scheme named the mixed parallel addressing scheme is presented for AMOLED displays, in which one compensation interval can be divided into the first compensation frame and the consequent N -1 post-compensation frames without periods of initialization and threshold voltage detection. The proposed driving scheme has the advantages of both high speed and low driving power due to the mixture of the pipeline technology and the threshold voltage one-time detection technology. Corresponding to the proposed driving scheme, we also propose a new voltage-programmed compensation pixel circuit, which consists of five TFTs and two capacitors (5T2C). In-Zn-O thin-film transistors (IZO TFTs) are used to build the proposed 5T2C pixel circuit. It is shown that the non-uniformity of the proposed pixel circuit is considerably reduced compared with that of the conventional 2T1C pixel circuit. The number of frames (N) preserved in the proposed driving scheme are measured and can be up to 35 with the variation of the OLED current remaining in an acceptable range. Moreover, the proposed voltage-programmed driving scheme can be more valuable for an AMOLED display with high resolution, and may also be applied to other compensation pixel circuits. Project supported by the State Key Development Program for Basic Research of China (No. 2015CB655000) the National Natural Science Foundation of China (Nos. 61204089, 61306099, 61036007, 51173049, U1301243), and the Fundamental Research Funds for the Central Universities (Nos. 2013ZZ0046, 2014ZZ0028).

  17. FPGA implementation of adaptive ANN controller for speed regulation of permanent magnet stepper motor drives

    This paper presents a novel adaptive artificial neural network (ANN) controller, which applies on permanent magnet stepper motor (PMSM) for regulating its speed. The dynamic response of the PMSM with the proposed controller is studied during the starting process under the full load torque and under load disturbance. The effectiveness of the proposed adaptive ANN controller is then compared with that of the conventional PI controller. The proposed methodology solves the problem of nonlinearities and load changes of PMSM drives. The proposed controller ensures fast and accurate dynamic response with an excellent steady state performance. Matlab/Simulink tool is used for this dynamic simulation study. The main contribution of this work is the implementation of the proposed controller on field programmable gate array (FPGA) hardware to drive the stepper motor. The driver is built on FPGA Spartan-3E Starter from Xilinx. Experimental results are presented to demonstrate the validity and effectiveness of the proposed control scheme.

  18. 400-MW adjustable-speed pumped-storage hydraulic power plant

    Kita, E. [Kansai Electric Power Co. Inc., Osaka (Japan); Bando, A.; Kuwabara, T. [Hitachi, Ltd., Tokyo (Japan)

    1995-02-01

    The performance of the 400 MW adjustable-speed pumped-storage hydraulic power plant of Okawachi Power Station, Kansai Electric Power Co., Inc., Japan is outlined. The plant adopts a cycloconverter for an exciter, and uses selectively one of three real power control modes such as fixed-frequency excitation, synchronous speed control and slip-phase control according to internal phase angles. The plant also adopts the operation mode giving priority to quick response to output commands, and the stator frequency detecting mode giving priority to response to power systems. The plant maintains an AFC capacity of {plus_minus}80 MW during pumping operation, and satisfies the intended performance requirements in both generating and pumping modes. The overcurrent and overvoltage protection systems of which functions were ascertained to be effective through power system tests, are used to eliminate side effects due to use of the cycloconverter for an exciter. The specific transient phenomenon analysis system is also used for supporting maintenance works. 5 refs., 12 figs., 2 tabs.

  19. Neuro-fuzzy speed tracking control of traveling-wave ultrasonic motor drives using direct pulse width modulation

    Chau, KT; Chung, SW

    2002-01-01

    The traveling-wave ultrasonic motor (TUSM) drive offers many distinct advantages but suffers from severe system nonlinearities and parameter variations especially during speed control. This paper presents a new speed tracking control system for the TUSM drive, which newly incorporates neuro-fuzzy control and direct pulse width modulation to solve the problem of nonlinearities and variations. Increasingly, the proposed control system is digitally implemented by a low-cost digital signal proces...

  20. Neuro-Fuzzy Speed Tracking Control of Traveling-Wave Ultrasonic Motor Drives Using Direct Pulsewidth Modulation

    Chau, KT; Chung, SW; Chan, CC

    2003-01-01

    The traveling-wave ultrasonic motor (TWUM) drive offers many distinct advantages but suffers from severe system nonlinearities and parameter variations, especially during speed control. This paper presents a new speed tracking control system for the TWUM drive, which newly incorporates neuro-fuzzy control and direct pulsewidth modulation to solve the problem of nonlinearities and variations. The proposed control system is digitally implemented by a low-cost digital-signal-processor-based micr...

  1. Commissioning of 30 kVA variable-speed, direct-drive wind power plant

    Yildirim, Deniz

    Most wind turbines in service today employ induction generators together with a step-up mechanical gear so that the operational speed is close to the synchronous speed of two or four-pole generators. Because of the torque-speed characteristic of induction generators, the range of speed change is rather small; therefore, the operational speed can be considered to be nearly constant. Mechanical gears are subject to wear and tear, reduce reliability of the drive train and add to its weight. The maximum power that can be extracted from wind varies with its speed. Therefore, a direct-drive system, where a wind turbine is directly coupled to the generator shaft, is desirable along with a variable-speed operation. The variable-speed, direct-drive train described in this thesis consists of a lowspeed, permanent-magnet generator (60 to 120rpm), a resonant rectifier and a pulsewidth-modulated inverter. It supplies 30 kVA/20kW apparent/real power to the utility system at leading and unity power factors for a given DC link voltage. The amplitude and phase (leading, unity) of the AC current delivered to the utility system are controllable and the voltage/current wave forms at the point of common coupling satisfy standard IEEE-519. The overall efficiency of the drive train is about 83% (excluding the generator), whereby the rectifier has an efficiency of 86% and the inverter efficiency is around 95%. Using two different approaches (computer-aided and three-voltmeter methods), the losses of inductors are measured for the frequency range of 0 to 6 kHz. Measurement errors of both methods are less than 10% when measuring a few watts. The AC resistance increase of a Litz-wire inductor without a core is smallest among all of the inductors being tested. Stranding of individual (uninsulated) wires to obtain a flexible cable results in more losses than using a solid cable having the same cross-sectional area as that of a stranded cable. Nonsinusoidal voltages and currents in a power

  2. Speed Sensorless Vector Control of Induction Motor Drive with PI and Fuzzy Controller

    R. Gunabalan

    2015-02-01

    Full Text Available This paper directed the speed-sensorless vector control of induction motor drive with PI and fuzzy controllers.  Natural observer with fourth order state space model is employed to estimate the speed and rotor fluxes of the induction motor. The formation of the natural observer is similar to and as well as its attribute is identical to the induction motor. Load torque adaptation is provided to estimate the torque and rotor speed is estimated from the load torque, rotor fluxes and stator currents. There is no direct feedback in natural observer and also observer gain matrix is absent. Both the induction motor and the observer are characterized by state space model. Simple fuzzy logic controller and conventional PI controllers are used to control the speed of the induction motor in closed loop. MATLAB simulations are made with PI and fuzzy controllers and the performance of fuzzy controller is better than PI controller in view of torque ripples. The simulation results are obtained for various running conditions to exhibit the suitability of this method for sensorless vector control. Experimental results are provided for natual observer based sensorless vector control with conventional PI controller.

  3. Variable-Speed Induction Motor Drives for Aircraft Environmental Control Compressors

    Mildice, J. W.; Hansen, I. G.; Schreiner, K. E.; Roth, M. E.

    1996-01-01

    New, more-efficient designs for aircraft jet engines are not capable of supplying the large quantities of bleed air necessary to provide pressurization and air conditioning for the environmental control systems (ECS) of the next generation of large passenger aircraft. System analysis and engineering have determined that electrically-driven ECS can help to maintain the improved fuel efficiencies; and electronic controllers and induction motors are now being developed in a NASA/NPD SBIR Program to drive both types of ECS compressors. Previous variable-speed induction motor/controller system developments and publications have primarily focused on field-oriented control, with large transient reserve power, for maximum acceleration and optimum response in actuator and robotics systems. The application area addressed herein is characterized by slowly-changing inputs and outputs, small reserve power capability for acceleration, and optimization for maximum efficiency. This paper therefore focuses on the differences between this case and the optimum response case, and shows the development of this new motor/controller approach. It starts with the creation of a new set of controller requirements. In response to those requirements, new control algorithms are being developed and implemented in an embedded computer, which is integrated into the motor controller closed loop. Buffered logic outputs are used to drive the power switches in a resonant-technology, power processor/motor-controller, at switching/resonant frequencies high enough to support efficient high-frequency induction motor operation at speeds up to 50,000-RPA

  4. Sensorless Rotor-Field Oriented Controlled Induction Motor Drive with Particle Swarm Optimization Algorithm Speed Controller Design Strategy

    Yung-Chang Luo; Zhi-Sheng Ke; Ying-Piao Kuo

    2014-01-01

    A sensorless rotor-field oriented control induction motor drive with particle swarm optimization algorithm speed controller design strategy is presented. First, the rotor-field oriented control scheme of induction motor is established. Then, the current-and-voltage serial-model rotor-flux estimator is developed to identify synchronous speed for coordinate transformation. Third, the rotor-shaft speed on-line estimation is established applying the model reference adaptive system method based on...

  5. A low-power high-speed driving circuit for spatial light modulators

    朱明皓; 朱从义; 李文江; 张耀辉

    2012-01-01

    This paper describes the design and test of a novel custom driving circuit for multi-quantum-well (MQW) spatial light modulators (SLMs).Unlike previous solutions,we integrated all blocks in one chip to synchronize the control logic circuit and the driving circuits.Single-slope digital-to-analog converters (DACs) inside each pixel are not adopted because it is difficult to eliminate capacitor mismatch.64 column-shared 8-bit resistorstring DACs are utilized to provide programmable output voltages from 0.5 to 3.8 V.They are located on the top of 64 × 64 driving pixels tightly to match each other with several dummies.Each DAC performs its conversion in 280 ns and draws 80 μA.For a high speed data transfer rate,the system adopts a 2-stage shift register that operates at 50 MHz and the modulating rate achieves 50 K frames/s while dissipating 302 mW from a 5-V supply.The die is fabricated in a 0.35μm CMOS process and its area is 5.5 × 7 mm2.

  6. Direct Torque Control of Four Switch Three Phase Inverter fed Induction Motor Sensorless Speed Drive

    Mohamed K Metwally

    2014-10-01

    Full Text Available This paper presents sensorless speed control of induction motor (IM using four switch three phase inverter (FSTPI with direct torque and flux control (DTFC. The proposed sensorless DTFC system consists of an adaptive observer of rotor flux to accurately estimate stator resistance and speed simultaneously, without affecting drive performances. The switching technique for DTFC of IM using FSTPI in low power application is based on the principle of similarity between FSTPI and SSTPI (six switch three phase inverter, where the αβ plan is divided into 6 sectors and the formation of the voltage space vector is done in the same way as for SSTPI by using effective (mean vectors. This approach allows using the well-known established switching table of SSTPI for FSTPI. The simulation results indicates that the sensorless speed control of FSTPI fed IM with DTFC and adaptive observer provides accurate estimate, good trajectory tracking with different dynamics performance. The experimental results verify the effectiveness of the proposed method at different operating points.

  7. Type-2 fuzzy logic control based MRAS speed estimator for speed sensorless direct torque and flux control of an induction motor drive.

    Ramesh, Tejavathu; Kumar Panda, Anup; Shiva Kumar, S

    2015-07-01

    In this research study, a model reference adaptive system (MRAS) speed estimator for speed sensorless direct torque and flux control (DTFC) of an induction motor drive (IMD) using two adaptation mechanism schemes are proposed to replace the conventional proportional integral controller (PIC). The first adaptation mechanism scheme is based on Type-1 fuzzy logic controller (T1FLC), which is used to achieve high performance sensorless drive in both transient as well as steady state conditions. However, the Type-1 fuzzy sets are certain and unable to work effectively when higher degree of uncertainties presents in the system which can be caused by sudden change in speed or different load disturbances, process noise etc. Therefore, a new Type-2 fuzzy logic controller (T2FLC) based adaptation mechanism scheme is proposed to better handle the higher degree of uncertainties and improves the performance and also robust to various load torque and sudden change in speed conditions, respectively. The detailed performances of various adaptation mechanism schemes are carried out in a MATLAB/Simulink environment with a speed sensor and speed sensorless modes of operation when an IMD is operating under different operating conditions, such as, no-load, load and sudden change in speed, respectively. To validate the different control approaches, the system also implemented on real-time system and adequate results are reported for its validation. PMID:25887841

  8. Two Switch Adjustable-Speed Drive with Single-Phase Induction Machine

    Chomát, Miroslav; Lipo, T.

    Blacksburg, VA: National Science Foundation Engineering research Center, 2000, s. 381-385. [2000 CPES Power Electronics Seminar at Virginia Tech. Blacksburg, VA (US), 17.09.2000-19.09.2000] R&D Projects: GA MŠk ME 332 Grant ostatní: NSF(US) 9820434 Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  9. LC-filter Resonance Cancellation with DPWM Inverters in Adjustable Speed Drives

    Vadstrup, Casper; Wang, Xiongfei; Blaabjerg, Frede

    2015-01-01

    inverter and filter. Instead of abruptly clamp in one of the inverter legs and cause resonance in the filter. This method will charge or discharge the filter capacitor before clamping, this way the capacitor current is zero, and the capacitor voltage is equal to the average inverter voltage. Thereby, no...

  10. An EMC Evaluation of the Use of Unshielded Motor Cables in AC Adjustable Speed Drive Applications

    Hanigovszki, Norbert; Poulsen, J.; Spiazzi, G.;

    2004-01-01

    -phase applications the occurrence of common-mode voltage is inherent due to asymmetrical output pulses. As a result, for electromagnetic compatibility (EMC) reasons, in most applications shielded cables are used between the inverter and the motor, implying high installation costs. The present paper discusses the use...... of cheaper, unshielded cables. A new method for measuring electromagnetic interference (EMI) from unshielded cables is proposed and measurement results are presented. The level of EMI is evaluated in different situations: without an output filter, with a classical LC output filter and with an...

  11. SPEED CONTROL OF PMBLDC DRIVE WITH GATE CONTROL METHOD USING CONVENTIONAL AND FUZZY CONTROLLER

    T.V.NARMADHA,

    2010-11-01

    Full Text Available The paper presents simulation results of fuzzy logic and conventional proportional integral controller for the sensorless speed control of permanent magnet brushless dc (PMBLDC motor using Gate control method. Although conventional PI controllers are widely used in the industry due to its simple control structure and ease of implementation, these controllers pose difficulties under the conditions of nonlinearity, load disturbances and parametric variations. Moreover PI controllers require precise linear mathematical models. In the paper, the performance of the permanent magnet brushless dc motor drive is examined with the aid of the fuzzy logic controller. The fuzzy logic controller shows improved performance compared to the conventional PI speed controller. The module of the Three Phase inverter system controlled Permanent magnet Brushless DC motor is simulated using PI and Fuzzy Logic Controller and implemented in closed loop model. . By simulation, the characteristics of the PMBLDCM system are investigated. THD analysis for the methods is presented. The simulation results indicate FLC has improved performance.

  12. Application of modern control theory to variable-speed drive. Gendai seigyo riron no kudo system eno oyo

    Tanisaka, A.; Yano, K.; Umida, H. (Fuji Electric Co. Ltd., Tokyo (Japan))

    1991-10-10

    Application of a modern control theory to drive systems for industrial facilities was reviewed. On a modern control theory, an observer, LQI control (integral optimum regulator), model following control, and adaptive identification were discussed briefly. The following were given as application examples of a modern control theory to practical facilities, the control for depressing impact drop in mill driving for steel rolling, the control for depressing axial torsional vibration in motor connected with load through a low stiffness axis, the control for depressing tension vibration developed in steel plates during cold rolling, the autotuning of parameters, and the instantaneous speed detection in combination of mean speed detection, disturbance torque observer and instantaneous speed calculation. In addition, as new trials for the drive systems, parametrization of three-freedom control systems and adaptive control in vector control were discussed. 9 refs., 21 figs., 1 tab.

  13. Establishing force and speed training targets for lumbar spine high-velocity, low-amplitude chiropractic adjustments*

    Owens, Edward F.; Hosek, Ronald S.; Sullivan, Stephanie G.B.; Russell, Brent S.; Mullin, Linda E.; Dever, Lydia L.

    2016-01-01

    Objective: We developed an adjusting bench with a force plate supporting the lumbar portion to measure loads transmitted during lumbar manual adjustment. It will be used to provide force-feedback to enhance student learning in technique labs. The study goal is to define the learning target loads and speeds, with instructors as expert models. Methods: A total of 11 faculty members experienced in teaching Gonstead technique methods performed 81 simulated adjustments on a mannequin on the force plate. Adjustments were along 9 lumbopelvic “listings” at 3 load levels: light, normal, and heavy. We analyzed the thrusts to find preload, peak load, duration, and thrust rate. Results: Analysis of 891 thrusts showed wide variations between doctors. Peak loads ranged from 100 to 1400 N. All doctors showed clear distinctions between peak load levels, but there was overlap between high and low loads. Thrust rates were more uniform across doctors, averaging 3 N/ms. Conclusion: These faculty members delivered a range of thrusts, not unlike those seen in the literature for high velocity, low amplitude manipulation. We have established at least minimum force and speed targets for student performance, but more work must be done to create a normative adjustment to guide refinement of student learning. PMID:26600272

  14. Using Artificial Neural Networks for Energy Regulation Based Variable-speed Electrohydraulic Drive

    XU Ming; JIN Bo; YU Yaxin; SHEN Haikuo; LI Wei

    2010-01-01

    In the energy regulation based varibable-speed electrohydraulic drive system, the supply energy and the demanded energy, which will affect the control performance greatly, are crucial. However, they are hard to be obtained via conventional methods for some reasons. This paper tries to a new route: the definitive numerical values of the supply energy and the demanded energy are not required, except for their relationship which is called energy state. A three-layer back propagation(BP) neural network was built up to act as an energy analysis unit to deduce the energy state. The neural network has three inputs: the reference displacement, the actual displacement of cylinder rod and the system flowrate supply. The output of the neural network is energy state. A Chebyshev type II filter was designed to calculate the cylinder speed for the estimation of system flowrate supply. The training and testing samples of neural network were collected by the system accurate simulation model. After off-line training, the neural network was tested by the testing data. And the testing result demonstrates that the designed neural network was successful. Then, the neural network acts as the energy analysis unit in real-time experiments of cylinder position control, where it works efficiently under square-wave and sine-wave reference displacement. The experimental results validate its feasibility and adaptability. Only a position sensor and some pressure sensors, which are cheap and have quick dynamic response, are necessary for the system control. And the neural network plays the role of identifying the energy state.

  15. Combined Flux Observer With Signal Injection Enhancement for Wide Speed Range Sensorless Direct Torque Control of IPMSM Drives

    Blaabjerg, Frede; Andreescu, G.-D.; Pitic, C.I.;

    2008-01-01

    This paper proposes a motion-sensorless control system using direct torque control with space vector modulation for interior permanent magnet synchronous motor (IPMSM) drives, for wide speed range operation, including standstill. A novel stator flux observer with variable structure uses a combined...

  16. Gear Design Effects on the Performance of High Speed Helical Gear Trains as Used in Aerospace Drive Systems

    Handschuh, R.; Kilmain, C.; Ehinger, R.; Sinusas, E.

    2013-01-01

    The performance of high-speed helical gear trains is of particular importance for tiltrotor aircraft drive systems. These drive systems are used to provide speed reduction / torque multiplication from the gas turbine output shaft and provide the necessary offset between these parallel shafts in the aircraft. Four different design configurations have been tested in the NASA Glenn Research Center, High Speed Helical Gear Train Test Facility. The design configurations included the current aircraft design, current design with isotropic superfinished gear surfaces, double helical design (inward and outward pumping), increased pitch (finer teeth), and an increased helix angle. All designs were tested at multiple input shaft speeds (up to 15,000 rpm) and applied power (up to 5,000 hp). Also two lubrication, system-related, variables were tested: oil inlet temperature (160 to 250 degF) and lubricating jet pressure (60 to 80 psig). Experimental data recorded from these tests included power loss of the helical system under study, the temperature increase of the lubricant from inlet to outlet of the drive system and fling off temperatures (radially and axially). Also, all gear systems were tested with and without shrouds around the gears. The empirical data resulting from this study will be useful to the design of future helical gear train systems anticipated for next generation rotorcraft drive systems.

  17. DEVELOPMENT OF OPTIMUM SPEED DIAGRAMS FOR SMALL MOVEMENT OF AN ACTUATING DEVICE OF AС ELECTRIC DRIVE-WITH ELASTIC SHAFTING

    Dobrobaba Y. P.

    2013-10-01

    Full Text Available In this article we describe the optimum speed diagram of moving actuating device of АС electric drive with elastic shafting. Parameters, conditions of existence and dependence of the duration of the cycle from the angle of rotation of actuating device are defined as well

  18. Practical Wide-speed-range Sensorless Control System for Permanent Magnet Reluctance Synchronous Motor Drives via Active Flux Model

    Ancuti, Mihaela Codruta; Tutelea, Lucian; Andreescu, Gheorghe-Daniel;

    2014-01-01

    This article introduces a control strategy to obtain near-maximum available torque in a wide speed range with sensorless operation via the active flux concept for permanent magnet-reluctance synchronous motor drives. A new torque dq current reference calculator is proposed, with reference torque...

  19. Effects of fatigue on simulated high speed driving for prolonged periods

    Javier Ferrero; Alejandra Hervás; Cristina Civera; Francisco Tortosa

    2011-01-01

    Some evidences show that fatigue, that is one of the main effects of prolonged driving, can be more evident on elderly people. This work describes a study on the effects of prolonged driving using a driving simulator within a group of individuals older than 55 years. These individuals underwent medical and psychological examinations before and after the driving experience: on the one hand, Blood Pressure and PulseOximetry were monitored and they took the Driver-Test. Preliminary results sugge...

  20. Effects of fatigue on simulated high speed driving for prolonged periods

    Javier Ferrero

    2011-09-01

    Full Text Available Some evidences show that fatigue, that is one of the main effects of prolonged driving, can be more evident on elderly people. This work describes a study on the effects of prolonged driving using a driving simulator within a group of individuals older than 55 years. These individuals underwent medical and psychological examinations before and after the driving experience: on the one hand, Blood Pressure and PulseOximetry were monitored and they took the Driver-Test. Preliminary results suggest a decreasing performance after driving, especially affecting decision-making capacity

  1. Dynamic Modeling of Adjustable-Speed Pumped Storage Hydropower Plant: Preprint

    Muljadi, E.; Singh, M.; Gevorgian, V.; Mohanpurkar, M.; Havsapian, R.; Koritarov, V.

    2015-04-06

    Hydropower is the largest producer of renewable energy in the U.S. More than 60% of the total renewable generation comes from hydropower. There is also approximately 22 GW of pumped storage hydropower (PSH). Conventional PSH uses a synchronous generator, and thus the rotational speed is constant at synchronous speed. This work details a hydrodynamic model and generator/power converter dynamic model. The optimization of the hydrodynamic model is executed by the hydro-turbine controller, and the electrical output real/reactive power is controlled by the power converter. All essential controllers to perform grid-interface functions and provide ancillary services are included in the model.

  2. Swarming Speed Control for DC Permanent Magnet Motor Drive via Pulse Width Modulation Technique and DC/DC Converter

    A.S. Oshaba

    2013-05-01

    Full Text Available This study presents an approach for the speed control of a permanent magnet DC motor drive via Pulse Width Modulation (PWM technique and a DC/DC converter. The Particle Swarm Optimization (PSO technique is used to minimize a time domain objective function and obtain the optimal controller parameters. The performance of the proposed technique has been evaluated using various types of disturbances including load torque variations. Simulation results illustrate clearly the robustness of the controller and validity of the design technique for controlling the speed of permanent magnet motors.

  3. A Novel Adjustment Method for Shearer Traction Speed through Integration of T-S Cloud Inference Network and Improved PSO

    Lei Si

    2014-01-01

    Full Text Available In order to efficiently and accurately adjust the shearer traction speed, a novel approach based on Takagi-Sugeno (T-S cloud inference network (CIN and improved particle swarm optimization (IPSO is proposed. The T-S CIN is built through the combination of cloud model and T-S fuzzy neural network. Moreover, the IPSO algorithm employs parameter automation adjustment strategy and velocity resetting to significantly improve the performance of basic PSO algorithm in global search and fine-tuning of the solutions, and the flowchart of proposed approach is designed. Furthermore, some simulation examples are carried out and comparison results indicate that the proposed method is feasible, efficient, and is outperforming others. Finally, an industrial application example of coal mining face is demonstrated to specify the effect of proposed system.

  4. Adjusting for car occupant injury liability in relation to age, speed limit, and gender-specific driver crash involvement risk.

    Keall, Michael; Frith, William

    2004-12-01

    It is well established that older drivers' fragility is an important factor associated with higher levels of fatal crash involvement for older drivers. There has been less research on age-related fragility with respect to the sort of minor injuries that are more common in injury crashes. This study estimates a quantity that is related to injury fragility: the probability that a driver or a passenger of that driver will be injured in crashes involving two cars. The effects of other factors apart from drivers' fragility are included in this measure, including the fragility of the passengers, the crashworthiness of cars driven, seatbelt use by the occupants, and characteristics of crashes (including configuration and impact speed). The car occupant injury liability estimates appropriately includes these factors to adjust risk curves by age, gender, and speed limit accounting for overrepresentation in crashes associated with fragility and these other factors. PMID:15545071

  5. Free-standing few-layered graphene oxide films: selective, steady and lasting permeation of organic molecules with adjustable speeds

    Huang, Tao; An, Qi; Luan, Xinglong; Zhang, Qian; Zhang, Yihe

    2016-01-01

    A variety of small molecules with diameters around 1 nm possess a range of functions, such as antibiotic, antimicrobic, anticoagulant, pesticidal and chemotherapy effects, making these molecules especially useful in various applications ranging from medical treatment to environmental microbiological control. However, the long-term steady delivery (release or permeation) of these small molecules with adjustable and controllable speeds has remained an especially challenging task. In this study, we prepared covalently cross-linked free-standing few-layered GO films using a layer-by-layer technique in combination with photochemical cross-linkages, and achieved a controlled release of positively charged, negatively charged, and zwitterionic small molecules with adjustable and controllable speeds. The steady delivery of the small molecule lasted up to 9 days. Other functionalities, such as graphene-enhanced Raman spectra and electrochemical properties that could also be integrated or employed in delivery systems, were also studied for our films. We expect the special molecular delivery properties of our films to lead to new possibilities in drug/fertilizer delivery and environmental microbiological control applications.A variety of small molecules with diameters around 1 nm possess a range of functions, such as antibiotic, antimicrobic, anticoagulant, pesticidal and chemotherapy effects, making these molecules especially useful in various applications ranging from medical treatment to environmental microbiological control. However, the long-term steady delivery (release or permeation) of these small molecules with adjustable and controllable speeds has remained an especially challenging task. In this study, we prepared covalently cross-linked free-standing few-layered GO films using a layer-by-layer technique in combination with photochemical cross-linkages, and achieved a controlled release of positively charged, negatively charged, and zwitterionic small molecules with

  6. Swarming Speed Control for DC Permanent Magnet Motor Drive via Pulse Width Modulation Technique and DC/DC Converter

    A.S. Oshaba; E.S. Ali

    2013-01-01

    This study presents an approach for the speed control of a permanent magnet DC motor drive via Pulse Width Modulation (PWM) technique and a DC/DC converter. The Particle Swarm Optimization (PSO) technique is used to minimize a time domain objective function and obtain the optimal controller parameters. The performance of the proposed technique has been evaluated using various types of disturbances including load torque variations. Simulation results illustrate clearly the robustness of the co...

  7. Modulation of Premotor and Primary Motor Cortical Activity during Volitional Adjustments of Speed-Accuracy Trade-Offs.

    Thura, David; Cisek, Paul

    2016-01-20

    Recent work suggests that while animals decide between reaching actions, neurons in dorsal premotor (PMd) and primary motor (M1) cortex reflect a dynamic competition between motor plans and determine when commitment to a choice is made. This competition is biased by at least two sources of information: the changing sensory evidence for one choice versus another, and an urgency signal that grows over time. Here, we test the hypothesis that the urgency signal adjusts the trade-off between speed and accuracy during both decision-making and movement execution. Two monkeys performed a reaching decision task in which sensory evidence continuously evolves over the course of each trial. In different blocks, task timing parameters encouraged monkeys to voluntarily adapt their behavior to be either hasty or conservative. Consistent with our hypothesis, during the deliberation process the baseline and gain of neural activity in decision-related PMd (29%) and M1 cells (45%) was higher when monkeys applied a hasty policy than when they behaved conservatively, but at the time of commitment the population activity was similar across blocks. Other cells (30% in PMd, 30% in M1) showed activity that increased or decreased with elapsing time until the moment of commitment. Movement-related neurons were also more active after longer decisions, as if they were influenced by the same urgency signal controlling the gain of decision-related activity. Together, these results suggest that the arm motor system receives an urgency/vigor signal that adjusts the speed-accuracy trade-off for decision-making and movement execution. Significance statement: This work addresses the neural mechanisms that control the speed-accuracy trade-off in both decisions and movements, in the kinds of dynamic situations that are typical of natural animal behavior. We found that many "decision-related" premotor and motor neurons are modulated in a time-dependent manner compatible with an "urgency" signal that

  8. New possibilities with new technology: the Adjustable Speed Hydro (ASH) generator

    Generators with variable rotational speed can be the solution for the Norwegian power system. The technology is available and is already used abroad. As with all projects, investing in ASH must be based on economic profitability, where all advantages and disadvantages are considered, and on thorough techno-economic analyses. The article describes the fundamental principles of the ASH, its advantages, and discusses its possible installation in already existing power stations

  9. Modeling and Analysis of PI Controller Based Speed Control of Brushless DC Motor Drive.

    Mr.P.Nagasekhar Reddy

    2013-01-01

    The Brushless DC motors (BLDC) find widespread applications in domestic and industries due to their low and high power density and ease of speed control. To accomplish desired level of performance the motor requires suitable speed controllers. In case of permanent magnet Brushless DC motors, usually control of speed is reached by using proportional integral (PI) controller. Although the conventional PI controllers are widely used in the industry due to their simple control structure and ease ...

  10. Gravitational search algorithm based tuning of a PI speed controller for an induction motor drive

    Abd Ali, Jamal; Hannan, M. A.; Mohamed, Azah

    2016-03-01

    Proportional-integral (PI)-controller is very useful for controlling speed and mechanical load variables for the three-phase induction motor (TIM) operation. However, the conventional PI-controller has a very exhaustive trial and error procedure for obtaining it is parameters. In this paper, PI speed controller has been improved in it is design technique to suite TIM by utilizing a gravitational search algorithm (GSA) optimization technique. The mean absolute error (MAE) of the speed response has been used as an objective function. An optimal GSA based PI speed controller (GSA-PI) objective function is also employed to tune and minimize the MAE for developing the performance of the TIM in terms of changes speed and mechanical load. This experiment use space vector pulse width modulation (SVPWM) technique to create pulse width modulation for switching devices for three phase bridge inverter. Results obtained from the GSA-PI speed controller are compared with those obtained through particle swarm optimization (PSO) to validate the developed controller. Then it has been proved that the robustness of the GSA-PI speed controller is far better than that of the1 PSO controller in all tested cases in terms of damping capability and transient response under different mechanical loads and speeds.

  11. Emission characteristics of nonmethane hydrocarbons from private cars and taxis at different driving speeds in Hong Kong

    Guo, H.; Zou, S. C.; Tsai, W. Y.; Chan, L. Y.; Blake, D. R.

    2011-05-01

    Vehicular emissions are the major sources of a number of air pollutants including nonmethane hydrocarbons (NMHCs) in urban area. The emission composition and emission factors of NMHCs from vehicles are currently lacking in Hong Kong. In this study, speciation and emission factors of NMHCs emitted from gasoline-fuelled private cars and liquefied petroleum gas (LPG)-fuelled taxis at different driving speeds were constructed using a chassis dynamometer. Large variations in the contributions of individual NMHC species to total emission were observed for different private cars at different driving speeds. The variations of individual NMHC emissions were relatively smaller for taxis due to their relatively homogeneous year of manufacture and mileages. Incomplete combustion products like ethane, ethene and propene were the major component of both types of vehicles, while unburned fuel component was also abundant in the exhausts of private cars and taxis (i.e. i-pentane and toluene for private car, and propane and butanes for taxi). Emission factors of major NMHCs emitted from private cars and taxis were estimated. High emission factors of ethane, n-butane, i/ n-pentanes, methylpentanes, trimethylpentanes, ethene, propene, i-butene, benzene, toluene and xylenes were found for private cars, whereas propane and i/ n-butanes had the highest values for taxis. By evaluating the effect of vehicular emissions on the ozone formation potential (OFP), it was found that the contributions of olefinic and aromatic hydrocarbons to OFP were higher than that from paraffinic hydrocarbons for private car, whereas the contributions of propane and i/ n-butanes were the highest for taxis. The total OFP value was higher at lower speeds (≤50 km h -1) for private cars while a minimum value at driving speed of 100 km h -1 was found for taxis. At the steady driving speeds, the total contribution of NMHCs emitted from LPG-fuelled taxis to the OFP was much lower than that from gasoline

  12. The Effect of Rotor Cruise Tip Speed, Engine Technology and Engine/Drive System RPM on the NASA Large Civil Tiltrotor (LCTR2) Size and Performance

    Robuck, Mark; Wilkerson, Joseph; Maciolek, Robert; Vonderwell, Dan

    2012-01-01

    A multi-year study was conducted under NASA NNA06BC41C Task Order 10 and NASA NNA09DA56C task orders 2, 4, and 5 to identify the most promising propulsion system concepts that enable rotor cruise tip speeds down to 54% of the hover tip speed for a civil tiltrotor aircraft. Combinations of engine RPM reduction and 2-speed drive systems were evaluated. Three levels of engine and the drive system advanced technology were assessed; 2015, 2025 and 2035. Propulsion and drive system configurations that resulted in minimum vehicle gross weight were identified. Design variables included engine speed reduction, drive system speed reduction, technology, and rotor cruise propulsion efficiency. The NASA Large Civil Tiltrotor, LCTR, aircraft served as the base vehicle concept for this study and was resized for over thirty combinations of operating cruise RPM and technology level, quantifying LCTR2 Gross Weight, size, and mission fuel. Additional studies show design sensitivity to other mission ranges and design airspeeds, with corresponding relative estimated operational cost. The lightest vehicle gross weight solution consistently came from rotor cruise tip speeds between 422 fps and 500 fps. Nearly equivalent results were achieved with operating at reduced engine RPM with a single-speed drive system or with a two-speed drive system and 100% engine RPM. Projected performance for a 2025 engine technology provided improved fuel flow over a wide range of operating speeds relative to the 2015 technology, but increased engine weight nullified the improved fuel flow resulting in increased aircraft gross weights. The 2035 engine technology provided further fuel flow reduction and 25% lower engine weight, and the 2035 drive system technology provided a 12% reduction in drive system weight. In combination, the 2035 technologies reduced aircraft takeoff gross weight by 14% relative to the 2015 technologies.

  13. Experimental Performance Evaluation of a High Speed Permanent Magnet Synchronous Motor and Drive for a Flywheel Application at Different Frequencies

    Nagorny, Aleksandr S.; Jansen, Ralph H.; Kankam, M. David

    2007-01-01

    This paper presents the results of an experimental performance characterization study of a high speed, permanent magnet motor/generator (M/G) and drive applied to a flywheel module. Unlike the conventional electric machine the flywheel M/G is not a separated unit; its stator and rotor are integrated into a flywheel assembly. The M/G rotor is mounted on a flywheel rotor, which is magnetically levitated and sealed within a vacuum chamber during the operation. Thus, it is not possible to test the M/G using direct load measurements with a dynamometer and torque transducer. Accordingly, a new in-situ testing method had to be developed. The paper describes a new flywheel M/G and drive performance evaluation technique, which allows the estimation of the losses, efficiency and power quality of the flywheel high speed permanent magnet M/G, while working in vacuum, over wide frequency and torque ranges. This method does not require any hardware modification nor any special addition to the test rig. This new measurement technique is useful for high-speed applications, when applying an external load is technically difficult.

  14. Mechanical fault diagnostics for induction motor with variable speed drives using Adaptive Neuro-fuzzy Inference System

    Ye, Z. [Department of Electrical & amp; Computer Engineering, Queen' s University, Kingston, Ont. (Canada K7L 3N6); Sadeghian, A. [Department of Computer Science, Ryerson University, Toronto, Ont. (Canada M5B 2K3); Wu, B. [Department of Electrical & amp; Computer Engineering, Ryerson University, Toronto, Ont. (Canada M5B 2K3)

    2006-06-15

    A novel online diagnostic algorithm for mechanical faults of electrical machines with variable speed drive systems is presented in this paper. Using Wavelet Packet Decomposition (WPD), a set of feature coefficients, represented with different frequency resolutions, related to the mechanical faults is extracted from the stator current of the induction motors operating over a wide range of speeds. A new integrated diagnostic system for electrical machine mechanical faults is then proposed using multiple Adaptive Neuro-fuzzy Inference Systems (ANFIS). This paper shows that using multiple ANFIS units significantly reduces the scale and complexity of the system and speeds up the training of the network. The diagnostic algorithm is validated on a three-phase induction motor drive system, and it is proven to be capable of detecting rotor bar breakage and air gap eccentricity faults with high accuracy. The algorithm is applicable to a variety of industrial applications where either continuous on-line monitoring or off-line fault diagnostics is required. (author)

  15. Circuit Regulates Speed Of dc Motor

    Weaver, Charles; Padden, Robin; Brown, Floyd A., Jr.

    1990-01-01

    Driving circuit regulates speed of small dc permanent-magnet motor in tape recorder. Two nested feedback loops maintain speed within 1 percent of constant value. Inner loop provides coarse regulation, while outer loop removes most of variation in speed that remains in the presence of regulation by the inner loop. Compares speed of motor with commanded speed and adjusts current supplied to motor accordingly.

  16. Driving behaviour responses to a moose encounter, automatic speed camera, wildlife warning sign and radio message determined in a factorial simulator study.

    Jägerbrand, Annika K; Antonson, Hans

    2016-01-01

    In a driving simulator study, driving behaviour responses (speed and deceleration) to encountering a moose, automatic speed camera, wildlife warning sign and radio message, with or without a wildlife fence and in dense forest or open landscape, were analysed. The study consisted of a factorial experiment that examined responses to factors singly and in combination over 9-km road stretches driven eight times by 25 participants (10 men, 15 women). The aims were to: determine the most effective animal-vehicle collision (AVC) countermeasures in reducing vehicle speed and test whether these are more effective in combination for reducing vehicle speed; identify the most effective countermeasures on encountering moose; and determine whether the driving responses to AVC countermeasures are affected by the presence of wildlife fences and landscape characteristics. The AVC countermeasures that proved most effective in reducing vehicle speed were a wildlife warning sign and radio message, while automatic speed cameras had a speed-increasing effect. There were no statistically significant interactions between different countermeasures and moose encounters. However, there was a tendency for a stronger speed-reducing effect from the radio message warning and from a combination of a radio message and wildlife warning sign in velocity profiles covering longer driving distances than the statistical tests. Encountering a moose during the drive had the overall strongest speed-reducing effect and gave the strongest deceleration, indicating that moose decoys or moose artwork might be useful as speed-reducing countermeasures. Furthermore, drivers reduced speed earlier on encountering a moose in open landscape and had lower velocity when driving past it. The presence of a wildlife fence on encountering the moose resulted in smaller deceleration. PMID:26600095

  17. DAC to Mitigate the Effect of Periodic Disturbances on Drive Train using Collective Pitch for Variable Speed Wind Turbine

    Imran, Raja Muhammad; Hussain, Dil Muhammad Akbar; Soltani, Mohsen

    scheme to mitigate the effect of 3p flicker on drive train. 5MW wind turbine of the National Renewable Laboratories (NREL) is used as research object and results are simulated in MATLAB/Simulink. We designed the controller based on linearized model of the wind turbine generated for above rated wind speed...... and then tested its performance on the nonlinear model of wind turbine. We have shown a comparison of the results for proportional-integral(PI) and proposed DAC controller tested on nonlinear model of wind turbine. Result shows that our proposed controller shows better mitigation of flicker generated...

  18. Explicit Generalized Predictive Algorithms for Speed Control of PMSM Drives Fast Explicit Form with Field Weakening and Current Limitation

    Belda, Květoslav; Vošmik, D.

    Vienna: AIT Austrian Institute of Technology GmbH, 2013, s. 2833-2838. ISBN 978-1-4799-0224-8. ISSN 1553-572X. [IECON 2013. Vienna (AT), 10.11.2013-13.11.2013] R&D Projects: GA ČR(CZ) GAP102/11/0437 Institutional support: RVO:67985556 Keywords : PMSM drives * speed control * field weakening * current limitation * Generalized Predictive Control Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/separaty/2013/AS/belda-0398603.pdf

  19. Using LDR as Sensing Element for an External Fuzzy Controller Applied in Photovoltaic Pumping Systems with Variable-Speed Drives

    Geraldo Neves De A. Maranhão

    2015-09-01

    Full Text Available In the present paper, a fuzzy controller applied to a Variable-Speed Drive (VSD for use in Photovoltaic Pumping Systems (PVPS is proposed. The fuzzy logic system (FLS used is embedded in a microcontroller and corresponds to a proportional-derivative controller. A Light-Dependent Resistor (LDR is used to measure, approximately, the irradiance incident on the PV array. Experimental tests are executed using an Arduino board. The experimental results show that the fuzzy controller is capable of operating the system continuously throughout the day and controlling the direct current (DC voltage level in the VSD with a good performance.

  20. A hybrid inverter/cycloconverter-based variable-speed three-phase induction motor drive for single-phase inputs

    Chen, C. [Ford Motor Co., Dearborn, MI (United States). Scientific Research Lab.; Divan, D.M.; Novotny, D.W. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Electrical and Computer Engineering

    1995-05-01

    This paper presents a simple converter topology for driving a three-phase induction motor with a single-phase ac supply. Using only two active switches and a Triac, the converter can start the motor with high starting torque and low input current, and can bring the motor up to full speed using a very cost-effective, single-phase field-oriented control strategy. The converter supplies balanced output voltages at rated frequency with virtually no output distortion and with very high input power factor. In this paper, the capability contours for different speed ranges and various operating modules are addressed; the trade-offs between output torque, torque, ripple, input current distortion, and inverter rating are also explained, and the proposed control approaches are supported by simulation and test results.

  1. A Class of Speed Sensorless Sliding Mode Observers for Direct Torque Controlled Induction Motor Drives

    Lascu, Cristian; Boldea, Ion; Blaabjerg, Frede

    A family of speed-sensorless sliding-mode observers for induction motors has been developed. Three topologies have been investigated in order to determine their feasibility, parameter sensitivity and practical applicability. The salient feature of all schemes is that they do not require the rotor...... speed adaptation, that is, they are inherently sensorless observers. The most versatile is a dual-reference-frame observer. The other two schemes, implemented in stator frame and rotor frame, respectively, are simpler and are insensitive to detuning some of the motor parameters. Main theoretical aspects...

  2. Explicit Generalized Predictive Control of Speed and Position of PMSM Drives

    Belda, Květoslav; Vošmik, D.

    2016-01-01

    Roč. 63, č. 6 (2016), s. 3889-3896. ISSN 0278-0046 Institutional support: RVO:67985556 Keywords : current limitation * field weakening * motion control * permanent magnet synchronous motors * position control * predictive control * speed control Subject RIV: BC - Control Systems Theory Impact factor: 6.498, year: 2014 http://library.utia.cas.cz/separaty/2016/AS/belda-0457259.pdf

  3. Comparative Study between PI and FUZZY Logic Speed Controller in Vector Controlled PMSM Drive

    Kaushik Jash

    2014-04-01

    Full Text Available This paper is concerned with vector control of permanent magnet synchronous motor (PMSM using two different type of speed controller, one is PI controller and another is FUZZY logic controller. Although Proportional Integral Controller usually preferred as a speed controller due to its fixed gain and integral time constant but the performance of PI controller is affected by parameter variation, such as load changing, speed variation etc. In PI controller THD of the stator phase current is more and torque ripple also more. To avoid this problem here we used FUZZY logic controller. In this paper the mathematical model of PMSM, using the powerful simulation modeling capabilities of Matlab/Simulink is implemented. The entire PMSM control system is divided into several independent functional modules such as PMSM body module, inverter module and coordinate transformation module and Sinusoidal pulse width modulation (SPWM production module and so on. Here we used two loops, one is outer loop known as speed control loop, another is inner loop called current loop. we can analyzed a variety of simulation waveforms and it provide an effective means for the analysis and design of the PMSM control system.

  4. 高频斩波串级调速系统功率因数的分析与计算%Analysis and Calculation for Power Factor of the High-frequency Chopped Wave Cascade Speed Control Drive System

    张军伟; 王兵树; 万军; 甄亚

    2011-01-01

    相对于变频调速系统,高频斩波串级调速系统具有节能效率高、结构简单、技术难度小等优点,在交流调速中得到了广泛应用.但和传统串级调速一样,该系统的严重缺点之一是功率因数低,而且随着负载变化和速度的调节,系统功率因数的变化范围很大.所以有必要准确分析计算其功率因数.本文介绍了高频斩波串级调速系统的工作原理,在此基础上提出了一种新的计算高频斩波串级调速系统功率因数的简化算法,总结了影响高频斩波串级调速系统功率因数的几大因素,最后通过建立试验系统进行验证,证实该算法的可靠性,对实际工程设计有实用价值.%Compared with frequency conversion speed control, high-frequency chopped wave cascade speed control drive system has such advantages as good efficiency on energy saving, simple structure and little technical difficulty,etc. So, it is widely used in AC governing speed field. However, as the traditional cascade speed governing drive, low power factor is the same overt weakness to the high-frequency chopped wave cascade speed control drive system. In addition, the power factor could change in a large range with the speed adjustment and changing load. So it is very necessary to analyse and calculate the power factor accurately. A compact algorithm to calculate the power factor of chopped wave cascade speed control drive system is put forward on the basic of introduction of the radical theory about it. A few of factors impacting on the power factor of chopper cascade speed control drive system are summed up. At last, A simulation validating system is founded, and which prove that the algorithm is reliable and practical on engineering design.

  5. An enhanced Z-source inverter topology-based permanent magnet brushless DC motor drive speed control

    Geno Peter, P.; Rajaram, M.

    2015-08-01

    In this paper, an enhanced Z-source inverter (ZSI) is introduced for controlling the speed of permanent magnet brushless DC motor (PMBLDCM) drive. It is the extension of the conventional ZSI and the elements used in the circuit are the same as those of the conventional ZSI, except that the position of Inverter Bridge and diode would be exchanged from the classical circuit diagram. This exchanged circuit avoids the startup path of the inrush current and hence reduces the inrush current and improves the motor efficiency. Different modes of enhanced ZSI are studied with PMBLDCM. The voltage polarity of Z-source capacitors in the proposed circuit is the same as that of the input voltage polarity. Furthermore, to get the same voltage boost, the capacitor voltage stress is reduced to a significant extent. The speed control capability of the proposed brushless DC motor drive is compared with that of the conventional ZSI. The proposed ZSI is implemented in MATLAB/Simulink working platform and the output performance is evaluated. Also, the performance of voltage ratio is analysed both by simulation and mathematical models. All these analyses are known to express the innovative features of the proposed system.

  6. Structure of 15-Level Sub-Module Cascaded H-Bridge Inverter for Speed Control of AC Drive Applications

    R. Uthirasamy

    2015-02-01

    Full Text Available This paper deals with the implementation of a single phase 15-level Sub-Multilevel Cascaded H-Bridge Inverter (SMCHBI for variable speed industrial drive applications. It consists of sub-multilevel modules and H-bridge inverter configuration. Sub-multilevel switches synthesize stepped DC link voltage and current from the DC sources. H-bridge inverter switches renovate stepped DC link voltage and current into sinusoidal waveform. Compared with conventional Cascaded Multilevel Inverter (CMLI, the proposed system employs the reduced number of power switches, DC sources and gate driver requirements. The proposed system not only reduces the overall system cost but also reduces the voltage stress across the inverter switches. The proposed system does not required additional resonant soft switching circuits for Zero Voltage Switching (ZVS of inverter. In the proposed method, variable frequency method is adopted for the speed control of industrial induction motor drives. A prototype model of 15-level SMCHB is developed and the performance of the systems is validated experimentally.

  7. Social interactions dominate speed control in driving natural flocks toward criticality

    Bialek, William; Giardina, Irene; Mora, Thierry; Pohl, Oliver; Silvestri, Edmondo; Viale, Massimiliano; Walczak, Aleksandra

    2013-01-01

    Flocks of birds exhibit a remarkable degree of coordination and collective response. It is not just that thousands of individuals fly, on average, in the same direction and at the same speed, but that even the fluctuations around the mean velocity are correlated over long distances. Quantitative measurements on flocks of starlings, in particular, show that these fluctuations are scale-free, with effective correlation lengths proportional to the linear size of the flock. Here we construct models for the joint distribution of velocities in the flock that reproduce the observed local correlations between individuals and their neighbors, as well as the variance of flight speeds across individuals, but otherwise have as little structure as possible. These minimally structured, or maximum entropy models provide quantitative, parameter-free predictions for the spread of correlations throughout the flock, and these are in excellent agreement with the data. These models are mathematically equivalent to statistical phy...

  8. SPEED CONTROL OF PMBLDC DRIVE WITH GATE CONTROL METHOD USING CONVENTIONAL AND FUZZY CONTROLLER

    T.V.NARMADHA,; T. Thyagarajan

    2010-01-01

    The paper presents simulation results of fuzzy logic and conventional proportional integral controller for the sensorless speed control of permanent magnet brushless dc (PMBLDC) motor using Gate control method. Although conventional PI controllers are widely used in the industry due to its simple control structure and ease of implementation, these controllers pose difficulties under the conditions of nonlinearity, load disturbances and parametric variations. Moreover PI controllers require pr...

  9. Type-1 and Type-2 Fuzzy Logic and Sliding-Mode Based Speed Control of Direct Torque and Flux Control Induction Motor Drives - A Comparative Study

    Ramesh, Tejavathu; Panda, A. K.; Kumar, S. Shiva

    2013-08-01

    In this research study, the performance of direct torque and flux control induction motor drive (IMD) is presented using five different speed control techniques. The performance of IMD mainly depends on the design of speed controller. The PI speed controller requires precise mathematical model, continuous and appropriate gain values. Therefore, adaptive control based speed controller is desirable to achieve high-performance drive. The sliding-mode speed controller (SMSC) is developed to achieve continuous control of motor speed and torque. Furthermore, the type-1 fuzzy logic speed controller (T1FLSC), type-1 fuzzy SMSC and a new type-2 fuzzy logic speed controller are designed to obtain high performance, dynamic tracking behaviour, speed accuracy and also robustness to parameter variations. The performance of each control technique has been tested for its robustness to parameter uncertainties and load disturbances. The detailed comparison of different control schemes are carried out in a MATALB/Simulink environment at different speed operating conditions, such as, forward and reversal motoring under no-load, load and sudden change in speed.

  10. Recent developments and benefits of high-speed PWM inverter-fed induction-motor drive for gas filtration in nuclear power plants

    This paper will discuss new developments relating to the use of a high-speed inverter-fed induction-motor drive for gas filtration of the main gas circulator compartment in nuclear power stations. Conventional drives use low speed induction motors which operate from fixed supply frequencies of either 50 Hz or 60 Hz. Operating speeds are essentially constant and for a 2-pole, 50 Hz machine the speed is 2750 r/min approximately. Due to the low operating speed, the sizes of both the motor and the impeller are rather large. For this type of drive, fixed speed operation results in high capital and operational costs. The system environmental conditions of very dry helium are severe and the operating temperature and pressure are both high for this type of motor. The expected system life is 40 years approximately and does not allow maintenance. In operation the motor is fully submerged in the process gas. This contribution will present some of the results of a development program carried out by two Howden Group companies on a high-speed drive. (Author)

  11. High-Speed Current dq PI Controller for Vector Controlled PMSM Drive

    Mohammad Marufuzzaman

    2014-01-01

    Full Text Available High-speed current controller for vector controlled permanent magnet synchronous motor (PMSM is presented. The controller is developed based on modular design for faster calculation and uses fixed-point proportional-integral (PI method for improved accuracy. Current dq controller is usually implemented in digital signal processor (DSP based computer. However, DSP based solutions are reaching their physical limits, which are few microseconds. Besides, digital solutions suffer from high implementation cost. In this research, the overall controller is realizing in field programmable gate array (FPGA. FPGA implementation of the overall controlling algorithm will certainly trim down the execution time significantly to guarantee the steadiness of the motor. Agilent 16821A Logic Analyzer is employed to validate the result of the implemented design in FPGA. Experimental results indicate that the proposed current dq PI controller needs only 50 ns of execution time in 40 MHz clock, which is the lowest computational cycle for the era.

  12. Performance Analysis of DTC-SVM Sliding Mode Controllers-Based Parameters Estimator of Electric Motor Speed Drive

    Fatma Ben Salem

    2014-01-01

    Full Text Available This paper is concerned with a framework which unifies direct torque control space vector modulation (DTC-SVM and variable structure control (VSC. The result is a hybrid VSC-DTC-SVM controller design which eliminates several major limitations of the two individual controls and retains merits of both controllers. It has been shown that obtained control laws are very sensitive to variations of the stator resistance, the rotor resistance, and the mutual inductance. This paper discusses the performances of adaptive controllers of VSC-DTC-SVM monitored induction motor drive in a wide speed range and even in the presence of parameters uncertainties and mismatching disturbances. Better estimations of the stator resistance, the rotor resistance, and the mutual inductance yield improvements of induction motor performances using VSC-DTC-SVM, thereby facilitating torque ripple minimization. Simulation results verified the performances of the proposed approach.

  13. The use of variable speed drives for cost-effective energy savings in South African mine cooling systems

    Highlights: • Energy analysis of 20 South African mine cooling systems. • Energy savings and feasibility calculated for large-scale variable speed drive implementation. • An annual electricity saving of 144,721 MW h (32.2%) and CO2 emission reduction of 132 Mton can be realised. • Pump and fan application found more viable than chiller application. • Pilot implementation study shows pump electricity savings of 29.9%. - Abstract: An industrial energy efficiency improvement through the introduction of modern technology is an important demand-side management initiative. Cooling systems on South African mines have been identified as large electricity consumers. There is significant potential for energy efficiency improvement by the widespread introduction of variable speed drive (VSD) technology. An energy audit was conducted on 20 large mine cooling systems and potential savings and feasibility indicators were calculated. A pilot implementation study was also done on one mine to experimentally validate the estimated savings. In this paper, the results of the audit, the potential savings and the pilot study results are presented. It is shown that large-scale implementation of VSDs on mine cooling system pumps and fans is economically viable. A total annual electrical energy saving of 144,721 MW h, or 32.2%, can be achieved. An annual cost saving of US$6,938,148 and CO2 emissions reduction of 132 Mton is possible. The implementation of VSDs on mine chiller compressors will also result in large energy savings, but is not economically feasible at present. Results of the pilot study indicate an electricity savings of 29.9%. The results are important to decision makers and indicate the significant impact that widespread VSD usage on mine cooling systems can have on South African mine sustainability

  14. Effects of priming exercise on the speed of adjustment of muscle oxidative metabolism at the onset of moderate-intensity step transitions in older adults.

    De Roia, Gabriela; Pogliaghi, Silvia; Adami, Alessandra; Papadopoulou, Christina; Capelli, Carlo

    2012-05-15

    Aging is associated with a functional decline of the oxidative metabolism due to progressive limitations of both O(2) delivery and utilization. Priming exercise (PE) increases the speed of adjustment of oxidative metabolism during successive moderate-intensity transitions. We tested the hypothesis that such improvement is due to a better matching of O(2) delivery to utilization within the working muscles. In 21 healthy older adults (65.7 ± 5 yr), we measured contemporaneously noninvasive indexes of the overall speed of adjustment of the oxidative metabolism (i.e., pulmonary Vo(2) kinetics), of the bulk O(2) delivery (i.e., cardiac output), and of the rate of muscle deoxygenation (i.e., deoxygenated hemoglobin, HHb) during moderate-intensity step transitions, either with (ModB) or without (ModA) prior PE. The local matching of O(2) delivery to utilization was evaluated by the ΔHHb/ΔVo(2) ratio index. The overall speed of adjustment of the Vo(2) kinetics was significantly increased in ModB compared with ModA (P ModA (P < 0.05), suggesting an improved O(2) delivery. Our data are compatible with the hypothesis that, in older adults, PE, prior to moderate-intensity exercise, beneficially affects the speed of adjustment of oxidative metabolism due to an acute improvement of the local matching of O(2) delivery to utilization. PMID:22422668

  15. Temperature and Light Control of Three phase Induction Motor Speed Drive by PIC

    Barsoum, Nader

    2010-06-01

    PIC is a family of Harvard architecture microcontrollers made by Microchip Technology, derived from the PIC1640 originally developed by General Instrument's Microelectronics Division. The name PIC initially referred to "Peripheral Interface Controller". PICs are popular with the developers and the hobbyists due to their low cost, wide availability, large user base, extensive collection of application notes, free development tools, and serial programming (and re-programming with flash memory) capability. In modern days, PIC microcontrollers are used in the industrial world to control many types of equipment, ranging from consumer to specialized devices. They have replaced older types of controllers, including microprocessors. Also, there is a growing need for off-line support of a computer's main processor. The demand is going to grow with more equipment uses more intelligence. In the engineering field for instance, PIC has brought a very positive impact in designing an automation control system and controlling industrial machineries. Accordingly, this paper shows the change in the motor speed by the use of PIC in accordance to the light and level of temperature. The project focuses on programming the PIC by embedded software that detects the temperature and light signals and send it to 3 phase induction motor of 240 volt. A theoretical analysis and the practical approach in achieving this work goal have proved that PIC plays an important role in the field of electronics control.

  16. High- Speed railway lines in Germany: Experience in Tunnelling in Karstic Geology and Discussion oF Tunnel Driving Methods

    Rudolf Pottler

    2004-01-01

    In the course of Deutsche Bahn's new high - speed railway line between Nuremberg and Ingolstadt, a number of tunnels are being constructed, with a total length of about 15 km. One of the longest tunnel is the 7,250 m long Irlahüll tunnel.The tunnel was driven in karst geology. It was not expected that karst phenomena would be so widespread. This forced client, designer and contractor to take a new approach to the project. Different tools were developed to handle the problems on site. Additional site investigations had to be performed to identify karst phenomena in the vicinity of the tunnel. For validating the stability and serviceability of the tunnel, a new way of defining the probability of failure of the construction had to be found. Based on the experience of the tunnel driving at the high - speed railway line in Germany between Nuremberg and Ingolstadt, two different methods of tunnelling are discussed: Drill and blast ( New Austrian Tunnelling Method: NATM) and the use of tunnel boring machines (TBM).

  17. Minimization and identification of conducted emission bearing current in variable speed induction motor drives using PWM inverter

    A Ramachandran; M Channa Reddy; Ranjan Moodithaya

    2008-10-01

    The recent increase in the use of speed control of ac induction motor for variable speed drive using pulse width modulation (PWM) inverter is due to the advent of modern power electronic devices and introduction of microprocessors. There are many advantages of using ac induction motor for speed control applicatons in process and aerospace industries, but due to fast switching of the modern power electronic devices, the parasitic coupling produces undesirable effects. The undesirable effects include radiated and conducted electromagnetic interference (EMI) which adversely affect nearby computers, electronic/electrical instruments and give rise to the flow of bearing current in the induction motor. Due to the flow of bearing current in the induction motor, electrical discharge machining takes place in the inner race of the bearing which reduces the life of the bearing. In high power converters and inverters, the conducted and radiated emissions become a major concern. In this paper, identification of bearing current due to conducted emission, the measurement of bearing current in a modified induction motor and to minimize the bearing current are discussed. The standard current probe, the standard line impedance stabilization network (LISN)), the electronics interface circuits are used to measure high frequency common mode current, bearing current and to minimize the conducted noise from the system. The LISN will prevent the EMI noise entering the system from the supply source by conductive methods, at the same time prevents the EMI generated if any due to PWM, fast switching in the system, will not be allowed to enter the supply line. For comparing the results with Federal Communications Commission (FCC) and Special Committee on Radio Interference (CISPR) standards, the graphs are plotted with frequency Vs, line voltage in $dB{_\\mu} V$, common mode voltage in $dB{_\\mu} V$ and the bearing current in $dB_{\\mu} A$ with out and with minimizing circuits.

  18. Correlation of prefrontal cortical activation with changing vehicle speeds in actual driving: a vector-based functional near-infrared spectroscopy study

    Kouji Yamamoto; Hideki Takahashi; Toshinori Kato

    2013-01-01

    Traffic accidents occur more frequently during deceleration than during acceleration. However, little is known about the relationship between brain activation and vehicle acceleration because it has been difficult to measure the brain activation of drivers while they drive. In this study, we measured brain activation during actual driving using vector-based functional near-infrared spectroscopy. Subjects decelerated from 100 to 50 km/h (speed reduction task) and accelerated from 50 to 100 km/...

  19. Space and time harmonics related problems and their mitigation for position and speed sensorless slip-ring induction motor drives applications

    Subhasis Nandi

    2008-10-01

    There have been renewed interests in slip-ring induction machines due to their increasing use in both grid connected and stand-alone wind power generation schemes. Despite the squirrel cage induction generators’ advantages of being brushless, low-cost, needing less maintenance and having inherent overload protection, the biggest advantage of variable-speed wound rotor induction machines is in its doubled energy capture. Also in high power induction motor drives such as static Kramer drives or static Scherbius drives use of wound rotor induction motors is a must. Thus it becomes necessary to measure the speed of the machine for closed loop control for such high performance drives. Recently, a sensorless position and speed estimation scheme was proposed for wound rotor wind power generator. In this paper, the limitation of the scheme caused by space and time harmonics have been investigated. Simulation results have been presented to explain the mechanism of the space and time harmonics caused distortion of current. Experimental results showing the deterioration of speed detection scheme at light load for a slip-ring induction motor have been presented. Finally, improvements have been applied experimentally to obtain better speed estimation.

  20. 同调式带转动的无级变速%Stepless Speed of Synchronous Adjusting Belt Drive

    邢荣胜; 赵华

    2002-01-01

    通过对国内目前广泛采用的v型带无级变速传动装置中存在的问题进行剖析,并根据实际需要,设计出一种结构简单,调速灵活,操作方便的同调式带传动无级变速装置.

  1. Chapter 18: Variable Frequency Drive Evaluation Protocol

    Romberger, J.

    2014-11-01

    An adjustable-speed drive (ASD) includes all devices that vary the speed of a rotating load, including those that vary the motor speed and linkage devices that allow constant motor speed while varying the load speed. The Variable Frequency Drive Evaluation Protocol presented here addresses evaluation issues for variable-frequency drives (VFDs) installed on commercial and industrial motor-driven centrifugal fans and pumps for which torque varies with speed. Constant torque load applications, such as those for positive displacement pumps, are not covered by this protocol. Other ASD devices, such as magnetic drive, eddy current drives, variable belt sheave drives, or direct current motor variable voltage drives, are also not addressed. The VFD is by far the most common type of ASD hardware. With VFD speed control on a centrifugal fan or pump motor, energy use follows the affinity laws, which state that the motor electricity demand is a cubic relationship to speed under ideal conditions. Therefore, if the motor runs at 75% speed, the motor demand will ideally be reduced to 42% of full load power; however, with other losses it is about 49% of full load power.

  2. Improvements in High Speed, High Resolution Dynamic Digital Image Correlation for Experimental Evaluation of Composite Drive System Components

    Kohlman, Lee W.; Ruggeri, Charles R.; Roberts, Gary D.; Handschuh, Robert Frederick

    2013-01-01

    Composite materials have the potential to reduce the weight of rotating drive system components. However, these components are more complex to design and evaluate than static structural components in part because of limited ability to acquire deformation and failure initiation data during dynamic tests. Digital image correlation (DIC) methods have been developed to provide precise measurements of deformation and failure initiation for material test coupons and for structures under quasi-static loading. Attempts to use the same methods for rotating components (presented at the AHS International 68th Annual Forum in 2012) are limited by high speed camera resolution, image blur, and heating of the structure by high intensity lighting. Several improvements have been made to the system resulting in higher spatial resolution, decreased image noise, and elimination of heating effects. These improvements include the use of a high intensity synchronous microsecond pulsed LED lighting system, different lenses, and changes in camera configuration. With these improvements, deformation measurements can be made during rotating component tests with resolution comparable to that which can be achieved in static tests

  3. Balanced Motions Realization for a Mechanical Regulators Free and Front-Wheel Drive Bicycle Robot Under Zero Forward Speed

    Yonghua Huang

    2013-08-01

    Full Text Available This paper focuses on a mechanical regulator free and front‐ wheel drive bicycle robot. We present a scheme to achieve the robotʹs track‐stand motion and circular motion under zero forward speed. In a situation where the robotʹs front‐bar is locked at 90 degrees, a kinetic constraint about the rotating rate of the front‐wheel and the yawing rate of the frame is derived. Using the constraint as a basis, we developed a simplified model of two independent velocities for the robot. The model suggests there is an under‐ actuated rolling angle in the system. Our control strategy originates from the under‐ actuated characteristics of the robot system. Concretely, we linearize the rolling angle of the frame and set the bicycle robot to regulate its tilting by rotating the front‐wheel. In the track‐stand motion, we control the position and the rotational rate of the front‐wheel; but in the circular motion, only the rotational rate of the front‐wheel is strictly regulated. Both simulations and physical experiments results show that our strategy is effective for achieving these two motions.

  4. Two-Phase Induction Motor Drives

    Gholam Reza Arab Markadeh

    2010-10-01

    Full Text Available The lack of variable-speed drives for two (single induction motor is a reality. This article attempts mainly to investigate the reasons for this lack of variable – speed drives. This paper deals with literature survey of various existing converter topologies, which have been proposed for adjustable speed single phase induction motor drives. Various converter topologies have been compared in this paper. Among these converter topologies, the adjustable frequency PWM inverter is the best choice for single-phase induction motor drives. However, adjustable-frequency drives have not been widely used with single-phase Induction motors. The open-loop constant V/F control law cannot be used with the single-phase induction motor drives as it is used with three phase motors. The variation of the operating frequency at lower speed range with constant load torque causes variation in motor's slip. A constant V/F control is suitable only over the upper speed range.

  5. Improvement of power system stability of an adjustable-speed pumped-storage generator/motor. Denryoku keito ni okeru kahensoku yosui hatsuden dendoki no keito anteido kojo ni kansuru kenkyu

    Michigami, T. (Tokyo Electric Power Co., Inc. (Japan)); Koyanagi, K. (Toshiba Corp., Tokyo (Japan))

    1994-02-20

    Recently, adjustable-speed pumped-storage generator/motor (adjustable-speed machine) is applied to power system as AFC adjusting force. This adjustable-speed machine has no problem on its stability and AC excitation control is carried out by the cycloconverter with speedy response since its being different from the conventional fixed-speed synchronous machine that the rotor speed becomes to adjustable. In this paper, aiming at the improvement of power system stability by using said adjustable-speed machine, the basic consideration on the rotor speed and reactive power control by AC excitation of the adjustable-speed machine; theoretical examination on the analysis model for analysing the system stability; analysis simulation results using two machine-pair infinite system for obtaining the basic properties of the improvement of power system stability; verification results on the effectiveness of improvement of power system stability as well as analysis model by simulative power transmission test are described. Further, the analysis simulation results on the effectiveness of improvement of power system stability by the models with the scale of practical system are reported. 11 refs., 15 figs., 9 tabs.

  6. Fuzzy Logic based Speed Control of a Six-Phase Series-Connected Two-Motor Drive System Feed from SVPWMVSI

    H. A. Hairik

    2008-01-01

    Full Text Available This paper presents a new topology for the control of a six-phase series-connectedtwo-motor drive system supplied from Space Vector Pulse Width Modulation (SVPWMVoltage Source Inverter (VSI. The two-motordrive system consists of a six-phase and athree-phase induction motors connected in series. These motors and the supply system havebeen analyzed to construct a field-orientedmodel for them. This model clearly shows thepossibility of independent of control of the two machines. A fuzzy logic based speed controller has been constructed and used to drive the two-motor in this work . The two-motor system, inverter system, and the fuzzy controller models are implemented and tested using Simulink/Matlab facilities. The presented results show the validity of the model to dowell for the sake of speed control under different operating conditions.

  7. Design and analysis of speed-sensorless robust stochastic L∞-induced observer for high-performance brushless DC motor drives with diminished torque ripple

    Highlights: ► A new sensorless BLDC motor drives based on L∞-induced observer has been proposed. ► A design and analysis of robust stochastic L∞-induced observer has been carried out. ► We present theoretical aspects of design for proposed, Kalman, sliding-mode methods. ► We compare three sensorless topologies from four aspects of simulation performance. ► Unique merit of proposed method makes it suitable for high-performance application. - Abstract: This paper aims to present an analysis and design of a high-performance speed-sensorless control scheme for a three-phase brushless DC (BLDC) motor drive by means of a novel observer technique in the induced L∞ norm setting, named robust stochastic L∞-induced observer, with the purpose of reducing torque ripple and increasing system robustness. The proposed observer is used for estimating the phase-to-phase trapezoidal back-electromotive-force (back-EMF) for the BLDC motor merely via utilizing measured line stator currents and voltages in such a way that by estimating the back-EMF, position and speed of the rotor is readily obtained. In contrast to the conventional back-EMF sensing methods, this strategy of utilized drive requires no filtering of current and voltage; furthermore, it does not suffer from any sensitivity to switching noises. Owing to that high-speed operation is vital for a motor, the varying input voltage method is used for realizing the minimization of commutation-torque-ripple in a parallel way to the proposed method since drive performance intensely degrades in this mode. Apart from analytic investigation of the proposed method, two other types of observers, namely, the sliding-mode observer and Kalman filter are compared with the proposed method for the aim of determining steady-state accuracy, dynamic performance, parameter and noise sensitivity, low-speed-operation performance, and computational complexity. Finally, the proposed system has been simulated in different operating

  8. Effects of excessive speeding and falling asleep while driving on crash injury severity in Ethiopia: a generalized ordered logit model analysis.

    Abegaz, Teferi; Berhane, Yemane; Worku, Alemayehu; Assrat, Abebe; Assefa, Abebayehu

    2014-10-01

    The severity of injury from vehicle crash is a result of a complex interaction of factors related to drivers' behavior, vehicle characteristics, road geometric and environmental conditions. Knowing to what extent each factor contributes to the severity of an injury is very important. The objective of the study was to assess factors that contribute to crash injury severity in Ethiopia. Data was collected from June 2012 to July 2013 on one of the main and busiest highway of Ethiopia, which extends from the capital Addis Ababa to Hawassa. During the study period a total of 819 road crashes was recorded and investigated by trained crash detectors. A generalized ordered logit/partial proportional odds model was used to examine factors that might influence the severity of crash injury. Model estimation result suggested that, alcohol use (Coef.=0.5565; p-value=0.017), falling asleep while driving (Coef.=1.3102; p-value=0.000), driving at night time in the absence of street light (Coef.=0.3920; p-value=0.033), rainfall (Coef.=0.9164; p-value=0.000) and being a minibus or vans (Coef.=0.5065; p-value=0.013) were found to be increased crash injury severity. On the other hand, speeding was identified to have varying coefficients for different injury levels, its highest effects on sever and fatal crashes. In this study risky driving behaviors (speeding, alcohol use and sleep/fatigue) were a powerful predictor of crash injury severity. Therefore, better driver licensing and road safety awareness campaign complimented with strict police enforcement can play a pivotal role to improve road safety. Further effort needed as well to monitor speed control strategies like; using the radar control and physical speed restraint measures (i.e., rumble strips). PMID:24866353

  9. A Sensorless Speed Control using Stator Ripple Currents for an Induction Motor Drive with Space Phasor PWM

    Mohapatra, KK; Gopakumar, K.; Baiju, MR; Murty, BV

    2004-01-01

    In the present paper a simple sensorless speed estimation scheme is presented, where the speed information is obtained from the motor phase current ripple. The scheme measures the stator current phasor deviation direction to determine the back EMF vector position during inverter zero vector switching states. This measurement of rotor flux position is done indirectly by computing the motor back EMF position which is orthogonal to the rotor flux position. The space vector PWM voltage output in ...

  10. Fault Tolerant Three-Phase AC Motor Drive Topologies:A Comparison of Features, Cost, and Limitations

    2005-01-01

    THE RELIABILITY of adjustables peed ac motor drives is an area of great interest for all members of the drives community and marketplace. This is particularly the case for the military, aerospace and automotive industries that are increasingly adopting variable speed drives in order to improve overall system efficiency and performance. There are certain safety critical applications such as steering, fuel pumps,

  11. Sensorless FOC Performance Improved with On-Line Speed and Rotor Resistance Estimator Based on an Artificial Neural Network for an Induction Motor Drive.

    Gutierrez-Villalobos, Jose M; Rodriguez-Resendiz, Juvenal; Rivas-Araiza, Edgar A; Martínez-Hernández, Moisés A

    2015-01-01

    Three-phase induction motor drive requires high accuracy in high performance processes in industrial applications. Field oriented control, which is one of the most employed control schemes for induction motors, bases its function on the electrical parameter estimation coming from the motor. These parameters make an electrical machine driver work improperly, since these electrical parameter values change at low speeds, temperature changes, and especially with load and duty changes. The focus of this paper is the real-time and on-line electrical parameters with a CMAC-ADALINE block added in the standard FOC scheme to improve the IM driver performance and endure the driver and the induction motor lifetime. Two kinds of neural network structures are used; one to estimate rotor speed and the other one to estimate rotor resistance of an induction motor. PMID:26131677

  12. 新型高速精密压力机传动机构研究%Research on new drive mechanism of a high-speed precision press

    柯尊芒; 鹿新建; 冯华伟; 王寒阳

    2013-01-01

    基于ADAMS动力学仿真软件,对卵形齿轮一曲柄滑块机构的新型高速精密压力机进行仿真研究,并与曲柄滑块机构的滑块位移、速度、加速度和驱动扭矩进行对比,有助于该型高速精密压力机的研发.%Based on ADAMS the oval gear-slider-crank mechanism of the new high-speed precision press was studied.The slider displacement,velocity,acceleration and driving torque were compared with the slider-crank mechanism.And this helps the development of the high-speed precision press

  13. SPEED CONTROL OF DC MOTOR WITH PIC 16F877

    İlhami ÇOLAK

    2005-02-01

    Full Text Available In this study, a PI controlled separately excited direct current (DC motor speed has been controlled using PIC 16F877 controller. In the PIC 16F877 programming as a PI controller, the speed of the motor is expected to follow the reference speed. Speed of the motor is measured by a tacho generator and then, the voltage applied to the motor is adjusted by a semiconductor power switch using pulse width modulation (PWM technique. Drive circuit was tested with 0.9 kW DC motor. Experimental results show that the drive circuit developed is very simple, useful, sensible, economical and flexible to apply for different applications.

  14. Rotor-dynamic design aspects for a variable frequency drive based high speed cryogenic centrifugal pump in fusion devices

    Superconducting magnets of large size are inevitable for fusion devices due to high magnetic field requirements. Forced flow cooling of the superconducting magnets with high mass flowrate of the order ∼3 kg/s is required to keep superconducting magnets within its safe operational boundaries during various plasma scenarios. This important requirement can be efficiently fulfilled by employing high capacity and high efficiency cryogenic centrifugal pumps. The efficiency > 70% will ensure overall lower heat load to the cryoplant. Thermo-hydraulic design of cryogenic centrifugal pump revealed that to achieve the operational regime with high efficiency, the speed should be ∼ 10,000 revolutions per minute. In this regard, the rotor-dynamic design aspect is quite critical from the operational stability point of view. The rotor shaft design of the cryogenic pump is primarily an outcome of optimization between thermal heat-in leak at cryogenic temperature level from ambient, cryogenic fluid impedance and designed rotation speed of the impeller wheel. The paper describes the basic design related to critical speed of the rotor shaft, rotor whirl and system instability prediction to explore the ideal operational range of the pump from the system stability point of view. In the rotor-dynamic analysis, the paper also describes the Campbell plots to ensure that the pump is not disturbed by any of the critical speeds, especially while operating near the nominal and enhanced operating modes. (author)

  15. A Class of Speed-Sensorless Sliding-Mode Observers for High-Performance Induction Motor Drives

    Lascu, Christian; Boldea, Ion; Blaabjerg, Frede

    2009-01-01

    require the rotor speed adaptation, i.e., they are inherently sensorless observers. The most versatile and robust is a dual-reference-frame full-order flux observer. The other two schemes are flux observers implemented in stator frame and rotor frame, respectively. These are simpler than the first one and...

  16. Robust optical speed tracking control of a current sensor less synchronous reluctance motor drive using a new sliding mode controller

    This paper describes the robust optimal incremental motion control of a current sensor less synchronous reluctance motor, which can be specified by any desired speed profile. The control scheme is a combination of conventional linear quadratic feed back control method and sliding mode control. A novel sliding switching surface is employed first, that makes the states of the synchronous reluctance motor follow the nominal trajectories (controlled by any type of nominal controller) when the motor parameter uncertainties and the disturbance load torque exist. The sliding mode controller has no reaching phase and produces small sliding mode control chattering. Then, using the above tracking controller, the well-known torque control schemes, maximum torque, constant current inductive axis control and maximum power factor control related to the synchronous reluctance motor are examined below and above the base speed. Finally the validity of our proposed control scheme is verified by computer simulation results

  17. Applied intelligent control of induction motor drives

    Chan, Tze Fun

    2011-01-01

    Induction motors are the most important workhorses in industry. They are mostly used as constant-speed drives when fed from a voltage source of fixed frequency. Advent of advanced power electronic converters and powerful digital signal processors, however, has made possible the development of high performance, adjustable speed AC motor drives.This book aims to explore new areas of induction motor control based on artificial intelligence (AI) techniques in order to make the controller less sensitive to parameter changes. Selected AI techniques are applied for different induction motor control s.

  18. Use of an expert system for the choice of variable speed drives; Application des techniques d`intelligence artificielle pour le choix des systemes d`entrainement a vitesse variable

    Chetate, B.; Khaldi, T.; Boudjennah, B.; Kara, C. [Institut National des Hydrocarbures et de la Chimie de Boumerdes (Algeria). Laboratoire des Economies d`Energie Electrique

    1998-06-01

    The electrical motors variable speed is a factor of energy saving. The interest of variable speed is justified by the fact that the investment is quickly redeemable. In this study, the authors present an expert system for the rational choice of variable speed drives (IES/VSD). This system allows to take into account the varieties of electrical motors, electronics converters and complex control systems. (authors) 12 refs.

  19. Correlation of prefrontal cortical activation with changing vehicle speeds in actual driving: a vector-based functional near-infrared spectroscopy study

    Kouji Yamamoto

    2013-12-01

    Full Text Available Traffic accidents occur more frequently during deceleration than during acceleration. However, little is known about the relationship between brain activation and vehicle acceleration because it has been difficult to measure the brain activation of drivers while they drive. In this study, we measured brain activation during actual driving using vector-based functional near-infrared spectroscopy. Subjects decelerated from 100 to 50 km/h (speed reduction task and accelerated from 50 to 100 km/h (speed increase task while driving on an expressway, in the daytime and at night. We examined correlations between average vehicle acceleration in each task and five hemodynamic indices: changes in oxygenated hemoglobin (ΔoxyHb, deoxygenated hemoglobin (ΔdeoxyHb, cerebral blood volume (ΔCBV, and cerebral oxygen exchange (ΔCOE; and the phase angle k (degrees derived from the other hemoglobin (Hb indices. ΔoxyHb and ΔCBV reflect changes in cerebral blood flow, whereas ΔdeoxyHb, ΔCOE, and k are related to variations in cerebral oxygen metabolism. Most of the resulting correlations with specific brain sites, for all the indices, appeared during deceleration rather than during acceleration. Faster deceleration resulted in greater increases in ΔdeoxyHb, ΔCOE, and k in the prefrontal cortex (r 0.4, p < 0.01, suggesting oxygen metabolism associated with transient ischemic changes. Our results suggest that vehicle deceleration requires more brain activation, focused in the prefrontal cortex, than does acceleration. From the standpoint of the indices used, we found that simultaneous analysis of multiple hemodynamic indices was able to detect not only the blood flow components of hemodynamic responses, but also more localized frontal lobe activation involving oxygen metabolism.

  20. Novel sensorless starting and low speed drive of cylindrical brushless DC motor using eddy current with un-known load; Uzudenryu wo riyoshita entogata brushless DC motor no futokutei fukaji ni okeru sensorless shidoho oyobi teisoku kudoho

    Tomita, M.; Doki, S.; Okuma, S. [Nagoya University, Nagoya (Japan); Yamaguchi, H. [The Aichi Electric Co. Ltd., Aichi (Japan)

    1998-04-01

    Sensorless starting and low speed drive of a cylindrical brushless DC motor with un-known load have been a difficult problem because an electromotive force does not arise enough at the starting and at low speeds and an inductance is constant irrespective of rotor position. In this paper, it is proposed to paste non-magnetic material and to measure a voltage of an opened phase to realize sensorless starting and low speed drives. The method is shown very feasible by experiments. 13 refs., 17 figs., 2 tabs.

  1. A high-speed multi-protocol quantum key distribution transmitter based on a dual-drive modulator

    Korzh, Boris; Houlmann, Raphael; Zbinden, Hugo

    2013-01-01

    We propose a novel source based on a dual-drive modulator that is adaptable and allows Alice to choose between various practical quantum key distribution (QKD) protocols depending on what receiver she is communicating with. Experimental results show that the proposed transmitter is suitable for implementation of the Bennett and Brassard 1984 (BB84), coherent one-way (COW) and differential phase shift (DPS) protocols with stable and low quantum bit error rate. This could become a useful component in network QKD, where multi-protocol capability is highly desirable.

  2. A Luenberger State Observer for Simultaneous Estimation of Speed and Rotor Resistance in sensorless Indirect Stator Flux Orientation Control of Induction Motor Drive

    Mabrouk Jouili

    2011-11-01

    Full Text Available The primary objective of this paper is to implement a sensorless indirect stator field oriented control (ISFOC of induction motor drive with rotor resistance tuning. Indeed, the proposed method for simultaneous rotor speed and rotor resistance estimation is based on Luenberger observer (LO. In order to estimate the rotor speed and the rotor resistance, an adaptive algorithm based on Lyapunov stability theory by using measured and estimated stator currents and estimated stator flux is proposed. The suggested control scheme, as a result, achieves a sound performance with computational complexity reduction obtained by using the analytical relation to determine the LO gain matrix. Again, the observer is simple and robust, when compared with the previously developed observers, and suitable for online implementation. For current regulation, however, this paper suggests a conventional Proportional-Integral (PI controller with feed-forward compensation terms in the synchronous frame. Owing to its advantages, an Integral-Proportional (IP controller is used for rotor speed regulation. The design, analysis, and implementation for a 3-kW induction motor are completely carried out using a dSpace DS 1104 digital signal processor (DSP based real-time data acquisition control (DAC system, and MATLAB/Simulink environment. Digital simulation and experimental results are presented to show the improvement in performance of the proposed algorithm.

  3. Comparative study of SVPWM (space vector pulse width modulation) and SPWM (sinusoidal pulse width modulation) based three phase voltage source inverters for variable speed drive

    We have performed comparative studies of Space Vector Pulse Width Modulation (SVPWM) and Sinusoidal Pulse Width Modulation (SPWM) techniques utilizing MATLAB tools. During these investigations, we carried out intensive simulations, comprehensively analyzed the obtained results and compared the harmonic density, power factor (PF), and switching losses of SVPWM and SPWM. It has been observed during investigations that if the switching frequency is high then losses due to harmonics are negligible, thus based on obtained results we suggested that the SVPWM technique is a more reliable solution. Because SVPWM utilizes DC bus voltage more efficiently, generates less Total Harmonic Distortion (THD) and has higher output quality it provides flexible control of output voltage and output frequency for Variable Speed Drive (VSD)

  4. Warp Drive: A New Approach

    Obousy, Richard

    2007-01-01

    Certain classes of higher dimensional models suggest that the Casimir Effect is a candidate for the cosmological constant. In this paper we demonstrate that a sufficiently advanced civilization could, in principal, manipulate the radius of the extra dimension to locally adjust the value of the cosmological constant. This adjustment could be tuned to generate an expansion/contraction of spacetime around a spacecraft creating an exotic form of field-propulsion. Due to the fact that spacetime expansion itself is not restricted by relativity, a faster-than-light 'warp drive' could be created. Calculations of the energy requirements of such a drive are performed and an 'ultimate' speed limit, based on the Planckian limits on the size of the extra dimensions is found.

  5. Alternating-Current Motor Drive for Electric Vehicles

    Krauthamer, S.; Rippel, W. E.

    1982-01-01

    New electric drive controls speed of a polyphase as motor by varying frequency of inverter output. Closed-loop current-sensing circuit automatically adjusts frequency of voltage-controlled oscillator that controls inverter frequency, to limit starting and accelerating surges. Efficient inverter and ac motor would give electric vehicles extra miles per battery charge.

  6. Stator insulation systems for medium voltage PWM drives fed motors

    This paper presents the partial results of a research project that studied the impact of medium voltage PWM ASD (adjustable speed drives) on motor stator insulation system. The findings from this study/ investigation have aided designers to improve the robustness of the insulation system used for ASD-fed motors, based on accelerated laboratory tests. (author)

  7. Modeling and Simulation of Flux-Optimized Induction Motor Drive

    Igried Dib Al-Khawaldeh

    2010-09-01

    Full Text Available The efficiency of induction motor drives under variable operating conditions can be improved by predicting the optimum flux that guarantees loss minimization. In this research, a loss-minimization scalar controller, based on determining of modulation index of IGBT inverter-based AC-to-AC converter, which corresponds to optimum flux, is proposed. For this purpose, mathematical models for total power losses as a function of magnetic flux, optimum flux as a function of operating speed and load torque, and modulation index as a function of optimum flux were analytically derived. Loss-minimized, scalar-controlled induction motor drive system was modeled, simulated and experimentally tested. The results have validated the effectiveness of this system in minimizing the motor operating losses, especially at light and medium loads. Also, the dynamic performance of the drive system has been improved. The proposed controller can be implemented in adjustable speed induction motor drive systems with variable loads, operating below rated speed.

  8. 可调式风扇传动安装座在客车上的应用%Application of an Adjustable Fan Drive Installed Stand to Bus/Coach

    叶成友

    2015-01-01

    Aiming at the abnormal wear and fracture problems of the belts with traditional fan drive equipment on a bus/coach, the author introduces a type of a solution of adjustable fan drive installation stand. This can completely solve the problem of fan drive belts abnormal wear and fracture, prolong the service life and reduce the maintenance cost.%针对目前客车上采用传统风扇传动装置存在皮带异常磨损和断裂的问题,介绍一种可调式风扇传动安装座的解决方案,彻底解决风扇传动皮带异常磨损和断裂的问题,延长使用寿命和降低维护保养成本。

  9. SPEED CONTROL OF DC MOTOR WITH PIC 16F877

    ÇOLAK, İlhami; Ramazan BAYINDIR

    2005-01-01

    In this study, a PI controlled separately excited direct current (DC) motor speed has been controlled using PIC 16F877 controller. In the PIC 16F877 programming as a PI controller, the speed of the motor is expected to follow the reference speed. Speed of the motor is measured by a tacho generator and then, the voltage applied to the motor is adjusted by a semiconductor power switch using pulse width modulation (PWM) technique. Drive circuit was tested with 0.9 kW DC motor. Experimental resul...

  10. An Improved Internal Model Principle Based Multivariable Nonlinear Control Method with Multiclass Nonharmonic Disturbances and Its Application to Speed Control of a Motor Drive System

    Yang Yu

    2014-01-01

    Full Text Available We study the global disturbance rejection problem for a class of general multivariable nonlinear systems with multiclass nonharmonic disturbances. The paper first introduces the importance and state of the art for disturbance rejection problem and describes the control problem in the form of mathematical expressions. It stresses the multiclass disturbances produced by the exosystem satisfying certain characteristic conditions. Then, the nonlinear internal models are designed in accordance with different characteristics of multiclass external disturbances. On the basis of introduction of the control law for disturbance-free system, a multivariable state feedback controller is devised in terms of the designed internal model equations and corresponding assumptions. A Lyapunov function is constructed to theoretically prove the global uniform boundness of all signals for the multivariable closed-loop system. Finally, the presented method is applied to implement the speed control and reject the multiclass nonharmonic disturbances for a two-input motor drive system. The simulation results testify correctness and effectiveness of the presented algorithm.

  11. Traffic Offences: Planned or Habitual? Using the Theory of Planned Behaviour and habit strength to explain frequency and magnitude of speeding and driving under the influence of alcohol.

    Lheureux, Florent; Auzoult, Laurent; Charlois, Colette; Hardy-Massard, Sandrine; Minary, Jean-Pierre

    2016-02-01

    This study addresses the socio-cognitive determinants of traffic offences, in particular of speeding and drinking and driving. It has two aims: (1) to test the hypothesis of a direct effect of habits on offences (i.e., independent of intentions) by employing a specific measure of habits (i.e., the SRIH) and (2) to analyse the offences by taking account of three distinct parameters: Frequency, usual magnitude (i.e., the most frequent deviation from the law) and maximal magnitude (i.e., the greatest deviation occasionally adopted) in order to represent more accurately the variability of the offending behaviours. A total of 642 drivers replied to a questionnaire. The results corroborate the idea that intention and habit are distinct and direct determinants of offences. The use of the SRIH dismisses the criticisms made with regard to the measure of past behaviour. The distinction between the three behavioural parameters proves to be relevant, as their determinants are not exactly similar. Finally, attitude and subjective norm had direct effects on the maximal magnitude and/or on the frequency of the offence. The discussion concerns the contribution of this study to the analysis of offences as well as its limitations and addresses the theoretical plausibility of the direct effects of attitude and the subjective norm. PMID:25656057

  12. Measures for speed management.

    2009-01-01

    Measures for speed management are essential for limiting the negative effects of driving too fast and at inappropriate speeds. To begin with, safe and credible speed limits need to be determined. Dynamic and variable speed limits that take into account the current circumstances, such as weather cond

  13. Improved Control of an Active-Front-End Adjustable Speed Drive with a Small dc-link Capacitor under Real Grid Conditions

    Klumpner, Christian; Liserre, Marco; Blaabjerg, Frede

    2004-01-01

    capacitors will be replaced by film capacitors in order to increase the ASD lifetime, but as this has lower energy density, the dc-link capacitance is expected to decrease. In these circumstances, operation under unbalanced and distorted supply voltage as well as high dynamic operation of the ASD makes the...... severe due to the small dc-link storage. To mitigate the latter problem it is proposed to pre-compensate the dc-link voltage reference signal considering the real grid voltage. Experiments show that the system handles successfully unbalance situation even with a small dc-link capacitor....

  14. Improvement of speed profile in induction motor drive using a new idea of PWM pulses generation base on artificial neural networks

    hojat moayedi rad; mohsen farshad; mohammad ali shamsi nejad

    2012-01-01

    Due to simplicity and low cost, induction motors are more useful than direct current motors. Hence the control of these motors is important. The pervious methods are fitted normally for a limited speed range and could not be used for high, low and very low speeds. The voltage model is suitable for high speed because the voltage drop of stator resistance is not small in low speed. The current model is suitable for low speed because of the problems of flux saturation at high speed. This researc...

  15. SPEED COMPLIANCE IN FREEWAY VARIABLE SPEED LIMIT SYSTEM – CASE STUDY OF THE PRAGUE CITY RING

    Michał MATOWICKI

    2016-03-01

    Full Text Available Many previous studies have confirmed the strong relationship between speed compliance and the frequency and severity of traffic accidents. Variable speed limit (VSL system as a measure to improve traffic safety enables the freeway system to change its posted speed limit based on various traffic and environmental conditions. Such system helps drivers to recognize the upcoming events, to adjust their driving style and in such way to address speed variation of the traffic flow. This is called speed harmonization. Although many studies researching the effect of VSL system on the traffic stream can be found, there are only few addressing its influence on the drivers behavior, particularly focusing on their tolerance limit and compliance, which has crucial meaning for future design of controlling algorithms. This study was prepared to inspect this grey area by studying the data from the VSL system at Prague city ring, describing the influence of the highway management system and its influence on drivers.

  16. Improving homogeneity by dynamic speed limit systems.

    Nes, N. van Brandenberg, S. & Twisk, D.A.M.

    2010-01-01

    Homogeneity of driving speeds is an important variable in determining road safety; more homogeneous driving speeds increase road safety. This study investigates the effect of introducing dynamic speed limit systems on homogeneity of driving speeds. A total of 46 subjects twice drove a route along 12

  17. Research of Ultrasonic Flow Meter with Driving-voltage and Gain Combined Adjustment%电压与增益联合调节的超声波流量计研制

    徐方明; 朱浩; 闫丽; 韩宇琦

    2013-01-01

    As an unimpeded measurement instrument,ultrasonic flow meters are used widely in the water supply industry,petrochemical engineering and power industry.The driving-circuits of ultrasonic transducer have an important influence on driving power and echo signal.This paper introduced the design of combined adjustment with driving-voltage of ultrasonic transducer and gain of echo signal,and provided the detailed hardware circuits and software control flow.Ultrasonic flow meters can use different driving-voltage and gain under different measure circumstances with combined adjustment of driving-voltage of ultrasonic transducer and gain of echo signal.The design enhanced driving-power of ultrasonic transducer,ensured better amplitude and SNR(signal to noise ratio) of echo signal which played important role in reducing the measuring blind area,increasing measuring distance,improving measuring accuracy and stability.%超声波流量计作为无阻碍式的流量测量仪器,被广泛应用于供水、石油、化工以及电力等工业场合,超声波换能器驱动电路直接影响着超声波发射功率和接收信号.文中首先介绍了超声波流量计换能器驱动电压和回波信号增益可联合调节的设计方案,其次描述了该方案实现的硬件电路原理及软件控制流程,最后通过试验证明通过对换能器驱动电压及回波增益的联合调节,超声波流量计可在不同工况下采用不同驱动电压和回波增益,有效增加换能器驱动功率,保证回波信号的幅值大小,提高其信噪比,对减小超声波流量计的测量盲区、增加测量距离、提高测量精度与稳定性等方面均有重要作用.

  18. Power electronic converters application in modern electrical drives for the pump stations

    The pumps are the most used working machines and they use about 20% of produced electrical energy. The pumps are typical continuous duty machines, their start up is with difficult conditions, and there are needs for the adjustable flow during their work. The modern solution for the pump drives is induction motors with soft starters or the current source inverters. Soft start with electronically change voltage is the most efficient way for the energy saving in the start up process. The classic pumps control systems is based on throttling, by pass and vanes rotation. The only way for the energy saving are adjustable speed drives, which are examined. The example shows that the investment in the adjustable speed drive will be paid back for a short time only with the lower electrical energy bills. (Author)

  19. 基于剔除机械效应的资本结构调整速度再检验%The Retest of Capital Structure′s Adjustment Speed Based on Exclusion of Mechanical Effects

    顾乃康; 邓剑兰

    2014-01-01

    The reason why research on capital structure′s adjustment speed has not yet won unanimous conclusion is that there may be a “mechanical effect” in conventional partial adjustment model .By decomposing the accounting identity of asset-liability ratio, this paper eliminates the mechanical effects caused by the change in asset size .And based on panel data of listed compa-nies in Shenzhen Stock Market and Shanghai Stock Market from 1998 to 2011 which issue A-shares only , this paper uses the two-stage estimation method to retest the adjustment speed and mean reversion of capital structure which are caused by active finan -cing behaviors of corporates .The empirical results show that:The adjustment speed of capital structure is about 13%under tra-ditional estimation which uses the change of asset-liability ratio as the dependent variable;but after excluding mechanical effects caused by changes in assets , the adjustment speed significantly drops to around 5%.The results show that , by excluding such mechanical effects , the corporate financing behaviors still induce mean reversion phenomenon of capital structure , but the speed of adjustment is so low that the trend of mean reversion is not obvious .%关于资本结构调整速度的研究至今仍未获得一致结论的原因之一在于传统的部分调整模型可能存在机械效应。通过对账面资产负债率的会计恒等式进行分解,剔除由资产规模变动引起的机械效应,在此基础上以1998年至2011年中国仅发行A股的非金融类上市公司面板数据为样本,采用两阶段估计法重新检验企业主动的融资行为对资本结构调整速度和均值反转的影响。研究结果表明,在传统的采用资产负债率变动作为因变量的估计下得到的资本结构调整速度约为13%,而剔除由资产规模变动引起的机械效应之后估计得到的调整速度明显下降到5%左右。这意味着在剔除由资产规模变动引起

  20. Improvement of speed profile in induction motor drive using a new idea of PWM pulses generation base on artificial neural networks

    hojat moayedi rad

    2012-02-01

    Full Text Available Due to simplicity and low cost, induction motors are more useful than direct current motors. Hence the control of these motors is important. The pervious methods are fitted normally for a limited speed range and could not be used for high, low and very low speeds. The voltage model is suitable for high speed because the voltage drop of stator resistance is not small in low speed. The current model is suitable for low speed because of the problems of flux saturation at high speed. This research presents a new method of PWM pulse generating in induction motors based on artificial neural networks in which, the switching pulses are generated by a multilayer feed-forward neural network that is trained by the voltage and current references. Also, for the estimation of required torque and flux information a multilayer perceptron is used. By application of this new method, there is no problem of stability at low and high speeds. The simulation results by matlab-simulink verify the proposed method in transient and steady-state operating modes.

  1. Enhanced dynamic Performance of Matrix Converter Cage Drive with Neuro-fuzzy approach

    R.R. Joshi; A.K. Wadhwani

    2007-01-01

    This paper proposes a new control algorithm for a matrix converter (MC) induction motor drive system. First, a new switching strategy, which applies a back-propagation neural network to adjust a pseudo dc bus voltage, is proposed to reduce the current harmonics of the induction motor. Next, a two-degree-of-freedom controller is proposed to improve the system performance. The controller design algorithm can be applied in an adjustable speed control system and a position control system to obtai...

  2. Optimisation of a high speed rotating composite drive shaft using a genetic algorithm - Hybrid high modulus-high resistance carbon solutions

    Montagnier, Olivier

    2011-01-01

    This study deals with the optimisation of subcritical and supercritical laminated composite drive shafts, based on a genetic algorithm. The first part focuses on the modelling of a composite drive shaft. Flexural vibrations in a simply supported composite drive shaft mounted on viscoelastic supports, including shear effects are studied. In particular, an analytic stability criterion is developed to ensure the integrity of the system. The torsional strength is then computed with the maximum stress criterion, assuming the coupling effects to be null. Torsional buckling of thin walled composite tubes is modelled using a combination between laminate theory and Fl\\"ugge theory. In the second part, the genetic algorithm is developed. The last part presents a comparative study between various composite materials solutions on a helicopter tail rotor driveline. In particular, hybrid tubes consisting of high modulus and high resistance carbon/epoxy plies are studied. These solutions make it possible to replace the conv...

  3. 气量无级调节系统的原理及应用%Principle and Application of HydroCOM Stepless Speed Adjustment System

    陈睿

    2012-01-01

    石油化工装置中的往复式压缩机常采用仪表阀旁路回流进行流量调节,造成大量能耗浪费。但在往复式压缩机上实施HydroCOM无级调节系统后,节能降耗效果十分显著。本文阐述了HydroCOM无级调节系统的节能原理、控制方案和联锁逻辑。%The bypass valve was often used to adjust the flow in reciprocating compressor in petrochemical plant, then a lot of energy were wasted. After HydroCOM system applied in reciprocating compressor, energy was saved a great deal. The principle of energy saving, the control program and the interlock logic were describled in detail.

  4. Stabilization of multi-machine power system by coordinated excitation control of multiple adjustable-speed generator/motors; Fukusu kahensoku hatsuden dendoki no reiji den`atsu kyocho seigyo ni yoru taki keito anteika

    Tatematsu, M.; Yokoyama, A. [The University of Tokyo, Tokyo (Japan)

    1996-01-20

    Since an adjustable-speed generator/motor (ASGM) is excited by AC voltage fed by a quick-response cycloconverter, a rotating speed of the rotor can be changed continuously. The ASGMs installed at some pumping-up power stations are now operated effectively for automatic frequency control under the lightly loaded condition at night by changing the pumping-up power due to the rotating speed change. It is expected, on the other hand, that under the generating condition in the daytime the ASGM will be used for enhancement of transient stability because it can generate or absorb active and reactive power independently of each other by AC excitation voltage control. This paper proposes a novel control method of excitation system of ASGM for improving the transient stability of a multi-machine power system including multiple ASGMs. The controller which is designed based on an energy function works well for the stability enhancement. In comparison with the conventional excitation control of synchronous generator and constant output control of ASGM, the effectiveness of the proposed method is shown by digital simulations. 10 refs., 5 figs., 2 tabs.

  5. Relationship between robust stability and power system damping enhancement by excitation control system of adjustable-speed generator; Kahensoku hatsudenki reiji denatsu seigyo kei ni yoru denryoku keito danpingu kojo koka to robasuto anteisei no kankei

    Shigeto, T.; Yokoyama, A. [Tokyo Univ. (Japan)

    1997-12-20

    Since Adjustable-Speed Generator (ASG) is excited by alternative voltage fed by a quick-response cycloconverter, the rotor speed can be changed continuously. The ASGs installed at sonic pumping-up power stations are now utilized for Automatic Frequency Control at night time and under the light load condition by changing the pumping-up power due to the rotating speed change. It is expected. on the other hand. that under the generating condition at day time ASG will be utilized for improvement of power system stability because it can change the active power and the reactive power independently of each other. This paper presents the effect of the excitation control system of ASG designed by robust pole allocation method which is one of the controller design techniques besed on H{infinity} control theory, on the power system damping enhancement. Eigenvalue analysis and digital time simulation are carried out for 10-machine longitudinal test power system including ASGs in order to evaluate the designed controller. 5 refs., 23 figs., 5 tabs.

  6. 四驱混合动力轿车分布式卡尔曼车速估计%Vehicle Speed Estimation Based on Distributed Kalman Filter for Four Wheel Drive Hybrid Electric Car

    赵治国; 杨杰; 吴枭威

    2015-01-01

    四驱混合动力轿车存在两轮/四轮多种驱动模式,针对某一驱动模式所设计的车速估计算法难以满足其他模式下车速估计的精度。考虑车辆不同驱动模式,利用车载传感器信号、后轮毂电机转矩信息以及既定档位下前轮转矩信息,提出两级分布式卡尔曼车速估计方法。考虑模型的强非线性,采用无味卡尔曼滤波(Unscented Kalman filter,UKF)算法设计主/子滤波器。同时为了提高UKF算法对模型误差、信号干扰的鲁棒性,实现了量测噪声均值和方差的自适应调节。基于Untire轮胎模型和滑移率递推方程,设计滑移率子滤波器;基于整车运动学模型,设计车速主滤波器;考虑不同驱动模式,利用子滤波器估计值在线融合得到车速。搭建 Carsim-Simulink 联合仿真平台,并分别在纯电动驱动模式和四轮混合驱动模式下,对车速估计算法进行仿真验证。结果表明,所提出的两级分布式卡尔曼车速估计方法能有效提高车速估计精度,并增强了对模型误差、量测信号干扰和不同驱动模式的鲁棒性。%The driving mode of hybrid electric car can be two-wheel or four-wheel drive. The speed estimation designed for a specific driving mode can hardly achieve high estimated accuracy in all modes. Focus on the changeable driving mode, a kind of distributed Kalman filter with two levels is proposed, by means of utilize vehicle sensors signals, the driving torque of rear in-wheel motors and the torque of front driving wheels at the given gear state. Considering the strongly nonlinear of the model, UKF is adopted to design the filter, and to improve the filter’s robustness on modeling error and signal noise, measurement noise mean and covariance is self-adaptive. Firstly, based on UniTire Model and recursive equation of slip rate, the sub-filter is developed; secondly, based on the vehicle Kinematics model, the master-filter can be

  7. Vehicle speed control transition module and method

    Mangan, E.L.; Conklin, B.

    1986-12-16

    An apparatus is described for automatically controlling the speed of a driverless vehicle comprising a stationary frame supporting first, second and third aligned drive tubes between tracks on the frame and which are adapted to support a driverless vehicle. A means is included for independently driving the first, second and third drive tubes such that each tube, when driven, rotates about its longitudinal axis, sensor means disposed along the frame for actuation by a driverless vehicle. The means for independently driving the drive tubes includes variable speed drive means responsive to the sensor means fro driving the second tube between first and second speeds. A method is described of automatically controlling the speed of a driverless vehicle which travels along first, second and third aligned drive tubes by frictional contact therewith. It maintains the first, second, and third drive tubes out of mechanical engagement with each other at all times, sensing the location of the driverless vehicle, driving the first drive tube at a first speed, driving the third drive tube at a second at a second speed. It also varies the speed of the second drive tube from the first speed to the second speed based on the sensed location of the driverless vehicle while the vehicle is driven by contact with the second drive tube.

  8. ADJUSTMENT FACTORS AND ADJUSTMENT STRUCTURE

    Tao Benzao

    2003-01-01

    In this paper, adjustment factors J and R put forward by professor Zhou Jiangwen are introduced and the nature of the adjustment factors and their role in evaluating adjustment structure is discussed and proved.

  9. 柴油机高速电磁阀驱动模块设计与故障诊断%Design of driving module and fault diagnosis for high-speed solenoid valve of diesel

    密刚刚; 周文华; 沈成宇; 郭修其

    2012-01-01

    According to the characteristic of driving current of the high-pressure pump and injectors' highspeed solenoid valve in the electrically controlled fuel injection system of diesel with time-pressure way, the driving circuit was designed, and the respective driving current was derived. Based on the driving circuit's characteristic, the corresponding circuit for fault detecting and diagnosing was proposed, and its veracity was proved through simulating circuit by software on the PC. The integrated fault diagnosis module was completed after the diagnosis algorithm was proposed. And the designed module was applied to an actual project. Then the experiment of actual driving and real-time fault diagnosing was operated on an electrically controlled diesel. The results showed that the pump and injector operated effectually and the parameter of the actual driving current was accurate with the system requirement. When faults occurred on the condition that the diesel worked on the middle or high speed, electronic control unit (ECU) could detect the faults and take effective actions to stop driving actuators timely. So the driving module satisfies the common rail's operating requirement. The detecting and diagnosing of open and short circuit of pump's solenoid valve and short to ground, open and inner short circuit of injector's solenoid valve is implemented. And its veracity and reliability satisfies the demand of system application.%针对时间压力式电控燃油系统的高速电磁阀——高压油泵及喷油器电磁阀的驱动电流特性,设计相应的驱动电路,得到符合要求的驱动电流.根据驱动电路特点,设计相应的故障诊断电路,并用仿真软件验证电路的准确性.在完成相应的诊断软件设计得到完整的诊断模块后,将设计的模块运用于实际工程中,在柴油机上完成了实际模块的驱动和故障诊断试验.试验结果表明:该驱动模块达到了共轨系统驱动要求,同时实现了油泵电

  10. Adjustment of the Short Track Speed Skaters'Psychology in Starting%短道速滑运动员起跑心理状态的调整

    耿丽; 刘翠佳

    2011-01-01

    比赛中短道速滑的起跑,对于整个比赛的过程和最终取得成绩起着至关重要的作用。运动员起跑时不良起跑心理状态表现为训练和比赛动机障碍、过度紧张性情绪障碍、焦虑性情绪障碍、抑制障碍,提出采取消除紧张情绪、消除焦虑和畏惧情绪、生物反馈法、集中注意力、念动训练法等方法与手段调整运动员赛前的心理状态。%The starting is crucial for a short track speed skater to perform through a competition and catch the final result. The skaters'bad psychology in starting shows the motivational perplexity of training and competition, the emotional handicap of overstrain and anxiety, the disorder of inhibitory control. The paper suggests clearing up their feelings of nervousness, anxiety and fear with the methods and means of biofeedback, focusing attention, ideomotion training.