基于无速度传感器和两级桥式逆变器的双三相感应电机控制系统研究

发布时间：2018-04-11 04:03

本文选题：双三相感应电机 + NovelSVPWM　；参考：《山东大学》2017年硕士论文

【摘要】：多相系统较传统的三相系统具有优势,本文的双三相感应电机控制系统是一种典型的多相系统。但是传统的双三相感应电机的驱动拓扑大都为单级桥式结构,在电源输入功率一定的情况下,采用单级桥式驱动拓扑的大功率多相系统会造成电源输入端大电流。本文提出基于两级串联桥式驱动拓扑的双三相感应电机控制系统,继承了传统多相系统优势,在电源功率一定的情况下,相较于单级桥式驱动拓扑虽然采用两级串联桥式驱动拓扑的大功率双三相感应电机控制系统需要电源输入端提供更高的电压,但电源输入端的电流会更小。所以该控制系统在某些对电源输入端电流幅值有限制的场合可以推广应用。本文针对两对极双三相感应电机,主要研究了基于两级串联桥式驱动拓扑下的新型控制策略。在产生脉宽调制波(PWM)方式上,把一种三相感应电机的Novel SVPWM发波方式通过双CLARK变换推广到双三相感应电机上,由于NovelSVPWM编程较传统SVPWM波更为方便且代码更少,但控制效果与传统SVPWM相似,所以简化了程序的繁琐程度。在开环控制方式上,在矢量控制的基础上,通过给定dq旋转坐标系下的q轴电压值Uq,作为合成电压矢量U的值对双三相感应电机进行开环控制。在闭环控制方式上,在转子磁链定向的矢量控制基础上进行改进,合理利用坐标变换中幅值变换,使六相合成矢量的幅值与两套三相合成矢量的幅值相同,仅在相位上有些许的差别,可以用相位补偿进行弥补,简化了控制系统。在经过理论分析、仿真实验和实验验证后,证明了该种方法的可行性,该算法在保证控制效果的同时减小了控制的复杂度。针对某些速度传感器很难推广的场合,采用模型参考自适应(MRAS)法通过采集每相电机定子侧相电流来对电机转速进行实时估计并作为闭环控制的速度反馈,并对MRAS算法做出两点改进:在可调模型中加入转速估计补偿系数和在MRAS算法中使用相对于控制系统独立的一套电机参数。本文在Matlab/Simulink中建立新型控制策略的仿真模型,分别针对基于两级串联桥式驱动拓扑的双三相感应电机的开环、闭环和改进后的MRAS算法做出仿真验证。在搭建的以DSP和FPGA为主控芯片的系统平台上进行编程,在实际的控制系统中实现上述理论的应用。为了说明算法的有效性及可行性,与另外两种结构的电机(定子绕组Y型接法的三相感应电机与基于两级串联H桥驱动拓扑的双三相感应电机)共同做出带载实验,但是在做对比实验时发现Y型接法的三相感应电机和基于两级串联桥式驱动拓扑的双三相感应电机的带载能力较弱,在分析算法和基于两级串联驱动拓扑的双三相感应电机和Y型三相感应电机的电机结构后,通过改进控制系统的算法解决了带载能力不足的现象。
[Abstract]:The multi-phase system has advantages over the traditional three-phase system, and the two-phase induction motor control system in this paper is a typical multi-phase system.However, the traditional driving topology of two-phase induction motor is mostly single-stage bridge structure. When the power input power is constant, the high-power multi-phase system with single-stage bridge drive topology will cause the high power input current.In this paper, a control system based on two-stage series bridge drive topology for two-phase induction motor is proposed, which inherits the advantages of the traditional multi-phase system and has a constant power supply.Compared with the single-stage bridge drive topology, the control system of high-power double-three-phase induction motor using two-stage series bridge drive topology needs higher voltage from the power input, but the current of the power input will be smaller.Therefore, the control system can be widely used in some cases where the current amplitude of the power input is limited.In this paper, a new control strategy based on two-stage series bridge drive topology is studied for two pairs of pole-dual three-phase induction motors.In the method of generating pulse width modulation (PWM), the Novel SVPWM generating mode of three-phase induction motor is extended to double three-phase induction motor by double CLARK transform, because NovelSVPWM programming is more convenient and less code than traditional SVPWM wave.But the control effect is similar to the traditional SVPWM, so it simplifies the complexity of the program.On the basis of vector control, the open loop control of double three phase induction motor is carried out by using the Q axis voltage value UQ in the given dq rotation coordinate system as the value of the synthetic voltage vector U.In the closed loop control mode, based on the vector control of rotor flux linkage orientation, the amplitude of six-phase synthetic vector is the same as that of two sets of three-phase synthetic vectors, and the amplitude of six-phase synthetic vector is equal to that of two sets of three-phase synthetic vectors by using the amplitude transformation of coordinate transformation.There are only some differences in phase, which can be compensated by phase compensation, which simplifies the control system.After theoretical analysis, simulation and experimental verification, the feasibility of this method is proved. The algorithm not only ensures the control effect but also reduces the control complexity.In view of the difficulty in popularizing some speed sensors, the model reference adaptive control (MRASS) method is used to estimate the motor speed in real time by collecting the stator side current of each phase motor and as the speed feedback of the closed-loop control.Two improvements are made to the MRAS algorithm: to add the compensation coefficient of speed estimation to the adjustable model and to use an independent set of motor parameters relative to the control system in the MRAS algorithm.In this paper, the simulation model of the new control strategy is established in Matlab/Simulink, and the simulation results of the open-loop, closed-loop and improved MRAS algorithm of the two-stage series bridge drive topology are given respectively.Based on the system platform with DSP and FPGA as the main control chip, the application of the above theory is realized in the actual control system.In order to illustrate the validity and feasibility of the algorithm, experiments are made with the other two kinds of motor (stator winding Y-connection three-phase induction motor and two-stage series H-bridge driven double-three-phase induction motor).But in the contrast experiment, it is found that the three-phase induction motor with Y-type connection and the double-three-phase induction motor based on two-stage series bridge drive topology have weak load capacity.After analyzing the structure of two-phase induction motor and Y-type three-phase induction motor based on two-stage series drive topology, the problem of insufficient load capacity is solved by improving the algorithm of control system.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP273;TM346

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