基于空间矢量调制策略270V高压直流笼型异步发电系统

在电力电子变换器控制的270V高压直流笼型异步电机发电系统中,采用控制发电机的瞬时转矩的策略来稳定输出电压,可使系统获得极好的动态性能.本文分析了这种控制策略输出电压纹波较大的主要原因是发电机的转矩脉动,而转矩脉动是由于一个控制周期中采用从开关表优选单一电压矢量对转矩、磁链实行滞环控制方式造成的.本文采用空间电压矢量调制(SVM)策略对异步发电机的瞬时转矩、磁链进行控制,并提出一种磁链矢量偏差法生成SVM参考电压矢量的方法.仿真和实验的结果验证了这种控制策略达到了使转矩脉动降低、输出电压的纹波减小的效果.

Cage Induction Generator Used in 270V DC Power System Generator System Based on Space Vector Modulation Strategy

The strategy of the instantaneous torque control (ITC) is applied to the new 270V high voltage DC power system which is composed of an induction cage generator and a power electronic 3-phase converter to make the output voltage regulated with good dynamic performance. This paper analyzes the reasons of the ripple in the output voltage under the ITC method. By researching, the ripple is caused by the generator torque fluctuating which is the result of choosing the single optimum one from the eight voltage space-vectors precomposed in the switch table to complete the hysteresis control of torque and flux in each control period. Also this paper introduces a new approach to control the torque and flux based on the space vector modulation (SVM) strategy and presents the method of obtaining the reference voltage vector of the SVM strategy based on the flux-error-vector which is the error between desired flux vector and the evaluated one. The results of simulation and experiments verify that the torque fluctuating and the ripple of output voltage are decreased.