并联型有源电力滤波器限流补偿策略研究

Research on current limiting compensation scheme of shunt APF

分析了系统突变情况时并联型有源电力滤波器(APF)发生过流的状况,从参考电流角度提出了截断限流和比例限流2种控制策略。前者将原参考补偿电流作比较限幅处理,得到新的参考电流;后者比较上周期参考补偿电流及APF最大允许补偿电流,得到一比例系数,参考该系数,得到本周期内新的参考电流。这2种方案都只对参考电流进行处理,控制实现简单,能充分利用APF的补偿能力,使小容量APF可安全运行于大谐波容量的系统中。就实现的复杂性、安全性及补偿效果而言,前者优于后者。最后,通过仿真研究验证了2种方案的可靠性和有效性。

During sudden disturbance period,over-current will occur in shunt APF（Active Power Filter）. From the view of reference currents ,two current limiting compensation schemes,truncating current limiting and proportioning current limiting,are proposed. The former limits the original reference compensation current to obtain new reference current,while the latter compares the reference compensation current of last period with the permissible maximal compensation current of APF to obtain the proportioning coef- ficient for the reference current of current period. Both schemes only deal with reference currents, easy to realize. The safe operation and full use of APF are ensured,which makes small capacity APF able to compensate large capacity harmonics of power systems. The former is better than the latter in implementation complicacy,security and compensation effect. Simulations prove the reliability and validity of both schemes.