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1.
为保证转子磁链定向准确,提出了一种在线校正转子磁链角的方法。通过检测空间电压矢量PWM中的零电压矢量期间相电流的变化量,计算得到转子磁链的准确角度,经调节器在线调节转差角频率大小,从而校正转子磁链角,达到了提高电机控制性能的目的。通过试验验证了理论的正确性和方法的有效性。  相似文献   

2.
感应电机的转子磁场定向控制中,磁场定向角的准确性影响着电机的转矩输出性能.在速度测量准确的场合,转子定向角主要受转子电阻误差的影响,而转子电阻校正又受到定子电阻误差的影响.目前,较少的论文对转子电阻和定子电阻同时进行补偿,且同时补偿下的稳定性问题也鲜有研究.该文提供了一种新型的基于MRAS的转子电阻和定子电阻补偿策略,...  相似文献   

3.
转子电阻变化对电力牵引感应电机起动转矩的影响   总被引:1,自引:0,他引:1  
列车运行范围广、路况复杂,在最困难的区段也要能够快速平稳起动,这就要求电力牵引感应电机能够提供足够大的起动转矩。影响起动转矩的因素主要是转子电阻的变化,而影响转子电阻变化的关键因素则是电机的温升。本文首先从转差频率和磁场定向两个方面分析了电力牵引感应电机的牵引特性,证明了转差频率和磁场定向的本质统一。在此基础上,分析了转子电阻变化对电力牵引感应电机转差频率和磁场定向的影响,以及对起动转矩的影响。利用TMS320F2812构成的控制系统,采用矢量控制技术,对电力牵引感应电机进行了起动转矩的理论验证实验。实验结果表明,转子电阻对电力牵引感应电机的起动转矩影响很大,温升是影响转子电阻变化的主要因素。  相似文献   

4.
A brief review and comparative characteristics of scalar control systems for traction induction motors for using in the traction electric drive are presented. It is shown that, despite the obvious advantages of the systems of vector control and direct torque control, scalar control systems have found wide application. The operation features of scalar control systems with stability0 of absolute slip and a minimum of stator current are considered. Based on the equivalent circuit of an induction motor taking into account the stator and rotor iron loss, a comparative evaluation of the considered scalar control systems based on the criterion of the efficiency coefficient taking into account the temperature of the stator and rotor windings is presented. Simulation results in the MATLAB environment for an 11-kW induction motor are presented. It is established that scalar control systems operating under the principle of a stator current minimum have an advantage, as this maintains the desired torque value with higher values of efficiency coefficient, which decreases electromagnetic loads and power loss. It is shown that it is necessary to take into account the influence of windings temperature on the stator voltage and the parameters of the control system in connection with its affect on the minimum stator current and optimal absolute slip ensuring extremal control by current minimum.  相似文献   

5.
裴维娜  范瑜  朱熙  李硕 《微电机》2011,44(5):41-45
针对盘式感应电机的参数特点,建立了盘式感应电机的数学模型和矢量控制模型。根据空间矢量脉宽调制原理和转子磁场定向的感应电机矢量控制理论,在Matlab/Simulink环境下建立了基于空间矢量脉宽调制的盘式感应电机矢量控制仿真模型,并利用模块化的设计思想对仿真模型进行了简化.分别对采用PWM和SVP-WM两种调制方式的矢量控制系统进行仿真,对仿真结果进行了分析和比较,结果表明SVPWM矢量控制系统转速响应迅速,电流、转矩波动小,仿真结果验证了建模方法的有效性。  相似文献   

6.
无刷直流电动机(BLDCM)存在转矩脉动的突出缺点,提出了一种基于直流环节电压控制和模糊PID控制器的新型混合控制策略,以抑制无刷直流电机的转矩脉。电路拓扑包含功率因数校正降压转换器和逆变器。降压转换器通过控制直流电路电压来降低换向转矩脉动,使用模糊PID控制器和脉冲宽度调制(PWM)技术的逆变器在导通区域提供适当的电流。 Buck变换器降低了通过控制直流环节电压换向转矩脉动,逆变器使用模糊PID和PWM技术提供导通区域的电流。该方法能够消除传导区转矩脉动,削弱换相区转矩脉动,仿真结果表明,该策略具有功率因数校正功能,可有效抑制转矩脉动,提升电机运行的鲁棒性。  相似文献   

7.
介绍了异步电机的直接转矩控制,它是基于定子坐标参考系和空间电压矢量脉宽调制(PWM)的高性能控制方法,也是一种磁链轨迹法,是从电机的角度出发,目的在于使交流电机产生圆形磁场。  相似文献   

8.
A novel field orientation scheme for current-fed induction motor drives is presented. The scheme is based on the closed-loop control of the torque angle and has the merits of being simple in implementation and insensitive to rotor resistance variations. The limits of previous field orientation schemes are reviewed. The torque angle control scheme is then formulated, and its application to induction motor (IM) drives fed by either current source inverters or current-controlled PWM inverters is illustrated. As an example, a current source inverter induction motor drive incorporating the scheme is designed, and its performance, which has been tested by simulation, is given  相似文献   

9.
感应电动机系统的变结构反推控制研究   总被引:2,自引:0,他引:2  
感应电动机系统的矢量控制为了进行电流(或电压)的3/2(或2/3)坐标变换需要进行转子转差或磁链角的计算,转子转差的计算容易受转子电阻变化的影响,而磁链角的直接计算容易受定子电阻变化的影响,因此避免转子转差或磁链角的计算对于感应电动机系统的控制是非常有意义的。文中把变结构反推控制运用于感应电动机系统的转矩和磁链控制,设计方法避开了转子转差或转子磁链角的计算,通过一定的坐标变换,基于定子侧的静止坐标系实现转矩和磁链的解耦控制。变结构反推控制设计能够实现快速的速度、转矩和磁链的渐近跟踪,同时系统控制器能够保证系统性能在电动机参数和外部负载变化时具有强的鲁棒性,通过Matlab仿真验证了系统设计的有效性和可行性。  相似文献   

10.
Since ordinary magnetic field poles of a PM (permanent magnet) motor generate higher harmonic flux, sinusoidal current will cause torque ripple. This is usually removed by short pitch winding, skew slot method, and so on. These methods have a drawback in terms of lower efficiency. Recently, new current control methods have been proposed to realize zero‐torque ripple and high‐efficiency drive at the same time. However, because the optimized reference current waveform obtained by these methods includes zero phase component, normal three‐phase full bridge inverter and dq coordinate control method cannot be used. This paper proposes a new current control method that can achieve zero‐torque ripple and maximum efficiency by using a normal three‐phase inverter. The three‐phase optimum current can be derived by satisfying the following conditions: (1) the direction of the current resultant vector always agrees with that of the electromotive force resultant vector, and (2) the scalar product of the two vectors is held constant. By means of modifying the coordinate transformation angle, this method can also make it possible to compensate torque pulsation error with maximum efficiency using general dq coordinate control method. The proposed method has been verified by experiments. © 2001 Scripta Technica, Electr Eng Jpn, 136(1): 57–64, 2001  相似文献   

11.
A novel compact slip‐power recovery system having sinusoidal rotor currents is proposed. In this system, a PWM boost rectifier is used as a substitute for a diode rectifier and a boost chopper in a conventional compact slip‐power recovery system. The conventional compact system has the disadvantage that it has a rectangular rotor current, and a motor torque with large ripple, because a diode rectifier remains in the system. Also, the rotor current cannot reach the current reference value near the synchronous speed, because the voltage drop caused by the resistance of the semiconductor devices and so on cannot be neglected when the rotor voltage becomes smaller near the synchronous speed. The use of the system proposed in this paper has solved these problems. The effectiveness of the proposed system was verified through computer simulations and experiments. As a result, the proposed system brings the sinusoidal rotor current, the small torque ripple, and wide controllable range near the synchronous speed. © 2002 Scripta Technica, Electr Eng Jpn, 139(2): 52–60, 2002; DOI 10.1002/eej.10012  相似文献   

12.
分析了永磁同步电机(PMSM)数学模型,设计了一种新颖的基于空间矢量脉宽调制技术的直接转矩控制(SVM-DTC)系统。利用两个PI控制器分别调节磁链和转矩实现对电机空间矢量中转矩和磁链两分量的解耦,同时采用基于转子位置和定子电流的定子磁链估算方法观测定子磁链,并设计滑模变结构无速度传感器来估算转子位置。仿真结果表明,所提出的方法能有效地估算定子磁链与转速,减小电磁转矩和定子磁链脉动,从而使系统具有较好的动、静性能。  相似文献   

13.
一种新型混合转子结构无轴承电动机磁悬浮力的矢量控制   总被引:7,自引:16,他引:7  
无轴承电机具有无机械磨损和噪声等优点,其转子旋转和悬浮的电磁转矩和磁悬浮力皆由电机本身产生。在对不同转子结构转矩和磁悬浮力进行有限元对比分析的基础上,该文提出了一种兼有永磁式和感应式转子共同优点的新型混合转子结构。该电机不仅能产生大的电磁转矩和磁悬浮力,而且提供了通过电流矢量定向实现悬浮力解耦控制的途径。基于数字信号处理器DSP(TMS320C32)和复杂可编程逻辑芯片CPLD(Xilinx),构建了混合转子无轴承电机的控制系统,实现了悬浮力矢量控制策略。试验结果表明该文所提出的新型无轴承电机的设计与控制策略是可行的。  相似文献   

14.
This paper proposes design and implementation of a direct torque controlled induction motor drive system. The method is based on control of separation between amplitude and angle of reference stator flux for determining reference stator voltage vector in generating PWM output voltage for induction motors. The objective is to reduce electromagnetic torque ripple and stator flux droop which result in a decrease in current distortion in steady-state condition. In addition, the proposed technique provides simplicity of a control system. The direct torque control is based on the relationship between instantaneous slip angular frequency and rotor angular frequency in adjustment of the reference stator flux angle. The amplitude of the reference stator flux is always kept constant at rated value. The system has been implemented to verify its capability such as torque and stator flux responses, stator phase current distortion both during dynamic and steady state with load variation, and low speed operation.  相似文献   

15.
利用定子磁链定向矢量控制方法,在同步坐标系下,双馈电机模型的基础上,建立了矢量控制方程式,通过控制转子电流的转矩分量和励磁分量来调节定子输出的有功功率和无功功率;并且利用Matlab/Simulink仿真软件,建立了系统的仿真模型,对系统的定子磁链矢量控制策略、风力机最大风能捕获和变速恒频运行方式进行了仿真实验研究,为机组的实际控制提供了参考和依据。  相似文献   

16.
This paper describes variable magnetization machines, which are capable of varying the magnetization state (MS) of permanent magnets during operation. A pulse current on the stator windings creates a magnetic field on the rotor; this can be used to manipulate the MS of the rotor magnets. Regulating the MS according to the machine operating condition can reduce machine losses. A proof‐of‐principle machine was designed and fabricated. A series of experiments was conducted to evaluate the torque–speed envelope and efficiency contours of the fabricated machine. A full‐scale machine was then designed with a modified magnetic circuit for application to an electric vehicle and evaluated using finite element analysis. A control strategy for the MS during machine operation is proposed, and the losses during a driving cycle with the strategy were evaluated.  相似文献   

17.
在异步电机的高性能控制方案中,为了降低开关损耗,采用优化脉宽调制(PWM)实现低开关频率下较小的电流谐波畸变。但在调制模式频繁切换时,优化PWM会产生电流和转矩冲击。因此,研究了将优化脉冲在线移位的闭环定子磁链轨迹跟踪控制方法,提出了由基于自控电机的降阶观测器与电机电流模型观测器组成的双观测器模型,实现了基波分量观测。结合电流谐波最小脉宽调制(CHMPWM)开关角,利用其重构参考磁链与实际磁链的差值,实现定子磁链轨迹跟踪。提出了无差拍下修正开关角小于2时的脉冲模式调整方案,消除了系统的动态调制误差,实现了低开关频率下异步电机的高性能控制。在开关频率为300 Hz以下的NPC型三电平逆变器上的仿真和试验证明了定子磁链轨迹跟踪控制策略的有效性。  相似文献   

18.
Abstract

Axially-laminated anisotropic (ALA) rotor reluctance synchronous motors (RSMs) have been proved recently capable of higher torque density, higher power factor and efficiency compared to their induction motor counterpart with the same stator. Vector current control systems have been proposed for such drives, based on maximum available torque constant current angle or minimum current for a given torque constant current angle or combined current-voltage control. In an effort to do away with the current controller limitations, especially in the high speed region, the paper proposes a torque vector control (TVC) system which is a direct stator flux and torque control through a table of optimum switchings in the voltage-source PWM inverter. A sliding mode speed controller is added. Extensive digital simulations are presented. They demonstrate the TVC fast response, wide speed range and load rejection performance.  相似文献   

19.
Abstract

Axially-laminated anisotropic (ALA) rotor reluctance synchronous motors (RSMs) have been proved recently capable of higher torque density, higher power factor and efficiency compared to their induction motor counterpart with the same stator. Vector current control systems have been proposed for such drives, based on maximum available torque constant current angle or minimum current for a given torque constant current angle or combined current-voltage control. In an effort to do away with the current controller limitations, especially in the high speed region, the paper proposes a torque vector control (TVC) system which is a direct stator flux and torque control through a table of optimum switchings in the voltage-source PWM inverter. A sliding mode speed controller is added. Extensive digital simulations are presented. They demonstrate the TVC fast response, wide speed range and load rejection performance.  相似文献   

20.
A new vector control system for permanent magnet synchronous motor drives has been developed. To stabilize the current control loop in the high‐rotating‐speed region, a novel configuration of current controller is introduced. The unique characteristic of the proposed current controller is that the current regulator is connected to the conventional motor model in a series. By analyzing the transfer characteristics of the control, it became clear that the influence of the coupling component between the dq axes can be deleted theoretically if the control parameters are set properly. The stability and torque response of the proposed vector control system were improved, and the effectiveness of the proposed controller was demonstrated by a time domain simulation and some experiments. In addition, the robustness of the controlling system was investigated experimentally. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 176(4): 61–72, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21123  相似文献   

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