共查询到20条相似文献,搜索用时 15 毫秒
1.
Telford D. Dunnigan M.W. Williams B.W. 《Industrial Electronics, IEEE Transactions on》2003,50(2):253-261
In a vector-controlled induction machine drive, accurate knowledge of the machine electrical parameters is required to ensure correct alignment of the stator current vector relative to the rotor flux vector, to decouple the fluxand torque-producing currents and to tune the current control loops. This paper presents a new method for online identification of the induction machine parameters required to tune a rotor-flux-oriented (RFO) vector control scheme. Accuracy of the slip frequency estimation required for RFO vector control is achieved by utilizing the parameter independent "flux pulse" rotor time constant estimation scheme, which utilizes short-duration pulses injected into the flux-producing current. The parameters required to tune the synchronous frame current control loops with a decoupling circuit are estimated using a recursive estimation scheme derived from the synchronous frame voltage equations. As the "flux pulse" scheme requires signal injection into the flux-producing current a new rotor time constant estimation scheme is presented, based on the sensitivity analysis of the recursive parameter estimation scheme. Simulation and experimental results are presented which demonstrate the effectiveness of the online parameter identification and control loop tuning technique. 相似文献
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Ohishi K. Hayasaka E. Nagano T. Harakawa M. Kanmachi T. 《Industrial Electronics, IEEE Transactions on》2006,53(3):795-802
Generally, a speed servo system of a vector-controlled induction motor has limitations of motor voltage and current. When the speed servo system has a large torque reference, the output of its PI controller is often saturated. In this case, the conventional servo system stops the integral calculation of its PI controller. However, this system often has a large overshoot and/or an oscillated response caused by both a windup phenomenon and phase error on the vector control condition. This paper proposes a new speed servo system considering voltage saturation for the vector-controlled induction motor. The proposed control method compensates the phase error on vector control condition quickly, and always keeps the vector control condition. The experimental results show that the proposed system well regulates the motor speed and the secondary magnetic flux for a large torque reference without a windup phenomenon. 相似文献
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Different vector-controlled structures are discussed, and their suitability for an economical and reliable industrial drive system is explored. From this, the design of a compact control hardware is derived, composed of an 80196 microcontroller and an ASIC (application-specific integrated circuit) for the generation of the pulsewidth modulation (PWM) signals. The drive system can be configured from a host computer or a hand-held servicing unit through a serial data link. Monitoring and diagnostic functions are included. A self-commissioning scheme permits the setting of the parameters for optimum dynamic performance of the induction motor. Various oscillograms demonstrate the behavior of the vector controller operating a 25-kVA PWM inverter 相似文献
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The estimation of rotor time constant, or rotor resistance, in a vector-controlled induction machine is necessary to achieve high-performance torque control. A new method of estimating the rotor resistance online, for use in a vector-controlled induction machine, is presented. It uses short duration pulses added to the constant flux reference current idse* and based on the resultant torque command current produced by a proportional-integral controller iqse * adjusts the rotor resistance estimate. This method of self-tuning the vector controller to the rotor time constant, when operating in a closed-loop speed control loop, does not produce torque pulsations when correctly tuned. In comparison to other online methods such as the extended Kalman filter and the extended Luenberger observer, this method does not require voltage sensors and is computationally simpler. The rotor resistance estimation technique is illustrated through simulation and practical implementation of a vector-controlled induction machine 相似文献
5.
Cardenas R. Pena R. Asher G.M. Clare J. Blasco-Gimenez R. 《Industrial Electronics, IEEE Transactions on》2004,51(3):603-614
This paper presents a novel control strategy for power smoothing. The system is based on a sensorless vector-controlled induction machine driving a flywheel. The problem of regulating the DC-link voltage against input power surges or sudden changes in load demand is addressed. The induction machine is controlled to operate in a wide speed range by using flux weakening above rated speed. A model reference adaptive system observer is used to obtain the rotational speed in the whole speed range. The observer parameters are adapted during flux weakening in order to obtain close tracking of the flywheel speed. Experimental results for the operation of the induction machine between zero to more than twice base speed are presented and discussed. 相似文献
6.
A large-capacity low-speed flywheel energy storage system based on a doubly-fed induction machine basically consists of a wound-rotor induction machine, and a cycloconverter or a voltage-source pulse width modulation (PWM) rectifier-inverter which is used as an AC exciter. Adjusting the rotor speed makes the machine either release the kinetic energy to the power system or absorb it from the utility grid. Thus, the machine has the capability of achieving not only reactive-power control, but also active-power control based on the flywheel effect of the rotating parts. This paper proposes a new control strategy for a doubly-fed induction machine intended as a flywheel energy storage system, which is characterized by the combination of vector control and decoupling control. The control strategy enables the induction machine to perform active-power control independent of reactive-power control even in transient states. The validity of the theory developed in this paper, along with the effectiveness and viability of the control strategy, is confirmed by computer simulation. In addition, this paper discusses a transient behavior of a magnetizing current in the induction machine 相似文献
7.
Tadakuma S. Tanaka I.S. Naitoh H. Shimane K. 《Power Electronics, IEEE Transactions on》1997,12(2):221-227
The authors propose a combined feedforward and feedback (FF/FB) control to improve robustness of vector-controlled induction motors. This FF/FB system maintains the quick response of the slip-frequency-type and is insensitive to parameter variation in cooperation with field-orientation control. Furthermore, the authors propose a neural network (NNW)-based vector control as a final goal of the FF/FB system 相似文献
8.
A start-up method for a speed sensorless stator-flux-orientedvector-controlled induction motor drive
Bose B.K. Patel N.R. Rajashekara K. 《Industrial Electronics, IEEE Transactions on》1997,44(4):587-590
This paper describes a zero-speed start-up method of a speed sensorless stator-flux-oriented direct vector-controlled induction motor drive with the help of a machine current model that does not use any speed signal. The machine starts smoothly with vector control at finite developed torque and then transitions to the standard direct vector-control mode with the voltage model signals as the speed begins to develop. The direct vector-control mode with voltage model uses programmable cascaded low-pass filters for flux-vector synthesis and enables the drive to operate from zero speed to field-weakening mode. As the drive speed falls to zero, the drive again transitions to start-up mode, so that it can be smoothly started again. The performance of the start-up scheme has been verified on a 100 kW electric vehicle drive 相似文献
9.
直接转矩控制技术是一种具有高静、动态性能的交流调速方法。本文以FPGA芯片为控制核心设计了感应电机直接转矩控制系统,用VHDL语言编写了系统的模糊控制软件.对软件中3/2变换模块、磁链和转矩估算模块、M/T测速模块、PI模块、模糊控制与启动模块、PWM模块进行详细的研究。然后通过实验初步验证了本文设计的基于模糊控制技术的感应电机直接转矩控制系统具有优良的动态和稳态性。 相似文献
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Hakan Akpolat Z. Asher G.M. Clare J.C. 《Industrial Electronics, IEEE Transactions on》1999,46(2):370-379
This paper addresses the problem of electronic emulation of both linear and nonlinear mechanical loads using a vector-controlled induction machine dynamometer. It is shown that a basic emulation scheme where the dynamometer torque demand is derived from the inverse dynamics of the emulated load is not generally viable, especially if the emulated load is part of a closed-loop speed control system. A new feedforward speed-tracking control scheme for the dynamometer is presented, which preserves the load dynamics and allows for emulation of a large class of nonlinear loads. An experimental rig is described using vector-controlled induction machines as the drive motor and dynamometer, and experimental results showing excellent emulation of both linear and nonlinear load dynamics are presented 相似文献
12.
Robust speed control of IM with torque feedforward control 总被引:1,自引:0,他引:1
The authors describe a digital signal processor-based (DSP-based) robust speed control for an induction motor (IM) with the load-torque observer and the torque feedforward control. In the proposed system, the load torque is estimated by the minimal-order state observer based on the torque component of a vector-controlled IM. Using the load-torque observer, a speed controller can be provided with a torque feedforward loop, thus realizing a robust speed control system. The control system is composed of a DSP-based controller, a voltage-fed pulsewidth modulated (PWM) transistor inverter and a 3.7 kW IM system. An eccentric load with an arm and a weight is coupled to the IM and it generates the sinusoidal gravitational fluctuating torque. Experimental results show robustness against disturbance torque and system parameter change 相似文献
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Space vector pulse width modulation of three-level inverter extending operation into overmodulation region 总被引:7,自引:0,他引:7
Mondal S.K. Bose B.K. Oleschuk V. Pinto J.O.P. 《Power Electronics, IEEE Transactions on》2003,18(2):604-611
Multilevel voltage-fed inverters with space vector pulse width modulation have established their importance in high power high performance industrial drive applications. The paper proposes an overmodulation strategy of space vector PWM of a three-level inverter with linear transfer characteristic that easily extends from the undermodulation strategy previously developed by the authors for neural network implementation. The overmodulation strategy is very complex because of large number of inverter switching states, and hybrid in nature, that incorporates both undermodulation and overmodulation algorithms. The paper describes systematically the algorithm development, system analysis, DSP based implementation, and extensive evaluation study to validate the modulator performance. The modulator takes the command voltage and angle information at the input and generates symmetrical PWM waves for the three phases of an IGBT inverter that operates at 1.0 kHz switching frequency. The switching states are distributed such that the neutral point voltage always remains balanced. An open loop volts/Hz controlled induction motor drive has been evaluated extensively by smoothly varying the voltage and frequency in the whole speed range that covers both undermodulation and overmodulation (nearest to square-wave) regions, and performance was found to be excellent. The PWM algorithm can be easily extended to vector-controlled drive. The algorithm development is again fully compatible for implementation by a neural network. 相似文献
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将PWM整流技术应用于能量回馈装置,是实现可再生能量回馈利用的经济而又环保的方法。介绍了能量回馈装置的主电路拓扑结构,并建立了该电路的数学模型,在此基础上,根据PWM整流器与交流电机的相似性,分析研究得到PWM整流器的虚拟磁链模型。从实现单位功率因素有源逆变控制出发,设计了PWM整流器的控制系统。通过Matlab/Simulink仿真表明,主电路设计合理,控制系统具有良好的动静态性能。 相似文献
17.
Libo Zheng Fletcher J.E. Williams B.W. Xiangning He 《Industrial Electronics, IEEE Transactions on》2008,55(5):1996-2005
A technique to improve the flux pattern within a five-phase induction machine is presented. The technique is developed through dual-plane vector control, with synchronized fluxes. By vector space decomposition, an analytical model and vector control of the machine are accomplished in two orthogonal vector planes,d1-q1 and ds-qs . The magnitude and rotating speed of the associated fluxes (fundamental and third harmonic) can be independently controlled in each vector plane. Synchronization control locks the relative position between the two fluxes. The resultant air-gap flux density is fully controlled, preventing iron saturation. This feature is especially important in reshaping the flux and back EMF waveform of the machine. A quasi-trapezoidal air-gap flux density distribution is achieved for better iron utilization and higher torque density. It is confirmed that compared with sinusoidal fluxing, the quasi-trapezoidal flux pattern will not lead to an oversized power inverter when improving machine torque density. The basic understanding and control scheme can be extended to a multiphase induction machine with a phase number greater than five. 相似文献
18.
Cardenas R. Pena R. Asher G. Clare J. 《Industrial Electronics, IEEE Transactions on》2001,48(3):625-635
This paper presents a novel control strategy for power smoothing in wind energy applications, especially those feeding a stand-alone load. The system is based on a vector-controlled induction machine driving a flywheel and addresses the problem of regulating the DC-link system voltage against both input power surges/sags from a wind turbine or sudden changes in load demand. The control is based on a feedforward compensation scheme augmented by a nonlinear controller. Two feedforward compensation schemes are discussed and the limitations and performance of each scheme are analyzed. Experimental results are presented which verify the excellent performance of the feedforward compensation technique 相似文献
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通过分析三相电压型PWM整流器的数学模型,建立了PWM整流器在两相旋转坐标系下的数学模型。研究了电压电流双闭环控制策略。基于空间矢量的思想,设计了三相电压型PWM整流器在Matlab/Simulink中的仿真模型。仿真结果表明,此控制方法有效可行。 相似文献