三相四开关并联型有源电力滤波器的指令电流确定方法

该文提供一种低成本的三相四开关并联型有源电力滤波器以适用于中、低压系统同时进行谐波电流抑制和无功功率补偿。通过对该三相四开关并联型有源电力滤波器工作原理的分析，采用直接将期望得到的电网正序基波电流作为该三相四开关并联型有源电力滤波器指令电流信号的控制方法。为保证在电网电压不平衡和电网出现短时故障等情况下，三相四开关并联型有源电力滤波器仍能安全有效的工作，引入正序基波电流幅值校正环节和正序基波电压相角检测器；为实现直流侧中点电压平衡，采用一种基于比例控制算法的直流侧电压偏置补偿器。相关的仿真与实验结果均证明该指令电流确定方法的可行性和有效性。

Study on Current Command Signal of Three-phase Four-switch Shunt Active Power Filter

A low-cost three-phase four-switch shunt active power filter (TFSAPF) suitable for both harmonic current suppression and reactive power compensation in low or medium voltage power system was proposed in this paper. After analyzing the compensating principle of TFSAPF, this paper proposed a control method based on the information of DC-side voltage, which took the desirable grid current as the control signal. In order to ensure the TFSAPF still working properly under unbalanced and distorted grid voltages, this paper added an amplitude adjustment for grid currents and an instantaneous phase angle detector. To keep neutral-point voltage balance, a neutral-point voltage compensator based on the proportional control algorithm was used in this paper. Some simulations and experiments were completed to verify the viability and effectiveness of the proposed control method.