电网有源电力滤波器电压控制仿真研究

Research on Voltage Control Simulation of Active Power Filter in Power Grid

直流侧电压的控制是并联型有源电力滤波器(Active power filter,APF)的关键技术之一。直流侧电压的大小将影响到APF的功率损耗和补偿性能。而在复杂的工业应用场所,各种负载的波动将会造成APF公共耦合点的电网电压的波动,进而影响到APF的补偿性能。以三相三线级联式H桥有源电力滤波器为例,分析了APF直流侧电压大小和变化影响APF补偿性能的问题,提出了一种将控制模块分成模块均值电压控制器和直流母线电压控制器两个部分的新型控制方法。通过Matlab仿真结果表明系统在跟踪输出补偿电流的同时,实现了直流侧电容电压的平衡与稳定控制。最后的结论是采用上述电压控制方法不仅能使有源电力滤波器能很好地跟踪补偿电网谐波,而且具有很好的动态响应和较高的检测精度,并且快速准确地实现各个变流器单元直流侧电压控制。

Control of DC link voltage is a key technique of shunt active power filters （APF）. The magnitude of the DC link voltage has an effect on power losses and the compensative ability of APF. In the complex industrial envi- ronment, the fluctuant load brings about the grid voltages fluctuation at in the point of common coupling （ PCC ）, then exerts an effect on the compensative ability of APF. Taking the three - phase three - wire cascade H - bridge ac- tive power filter as an example, the problems of APF DC side voltage and the influence of APF compensation perform- ance were analyzed. A control module was divided into two parts ： module mean voltage controller and DC bus voltage controller based on the new control method. The simulation results show that the system achieves the balance and stability control of the DC link voltage while tracking the output compensation current. The final conclusion is that the a- bove - mentioned voltage control method not only make the active power filter can track the harmonic compensation well, but also has good dynamic response and high detection accuracy, and realize the various converter Pressure Control of Unit DC link voltage quickly and accurately.