一种改进的单周控制直流侧有源电力滤波器及其稳态和动态研究

AN IMPROVED ONE CYCLE CONTROLLED DC SIDE ACTIVE POWER FILTER AND RESEARCH ON STEADY-STATE AND DYNAMICS

文中提出了一种改进的单周控制直流侧有源电力滤波器(DC侧APF)。这种DC侧APF并联在整流桥的直流侧,提供负载需要的谐波电流,使电源电流成为与电源电压同频同相的正弦电流。与传统的单相有源电力滤波器(APF)相 比,在不增加开关电压电流应力的情况下,功率开关的数量减少一半,简化了电路结构,降低成本。与传统的两级功率因数校正电路相比,新DC侧APF由于与负载并联,只提供谐波电流,所需处理的功率小、效率更高。新DC侧APF采用改进的单周控制方式,具有结构简单,控制效果好的优点。文中对改进前后2种控制方式的DC侧APF的稳态和动态性能进行了分析,结果表明,改进的控制方式不仅改善了补偿效果,而且扩展了系统的稳定区域。仿真和实验结果证实了理论分析的正确性。

This paper proposes an improved DC side active power filter(APF) with one cycle control. The proposed DC side active power filter is shunted at the DC side of the bridge rectifier to compensate the reactive and harmonic current for the rectifier load. In contrast to power factor correction(PFC), DC side APF is connected in parallel with the nonlinear load. Therefore, DC side APF provides only the harmonic and reactive current. In this case,only a small portion of the energy is processed, which may result in overall higher energy efficiency and higher power processing capability. Compared with the typical shunt APF, for which there is four power switches needed, the DC side APF only two active power switches are needed without adding the switch voltage and current stress. By using one cycle control, the control circuit is simple and robust which can be realized without multipliers, but simple analog circuits. And the steady and dynamic analyze of the control method is given, the result shows that not only the compensation property is enhanced, but also the stability region is broaden through the improved control method. All the findings are supported by experimental and simulation results.