三相四开关APF的SVPWM优化策略研究

Research on the SVPWM Optimizational Strategy of TFSAPF

针对三相四开关并联型有源电力滤波器(TFSAPF)的直流侧电容电压变化问题,通过分析不同开关模式的电路结构,总结了直流侧电容电压变化的原因,并给出了TFSAPF4个模值不全相等的有效空间电压矢量对直流侧电容电压的影响。提出了通过检测电容电压差值和电容电流方向来选择不同的等效零矢量以平衡直流侧电压的SVPWM优化策略。针对直流侧中点电位偏移问题,设计了一种基于检测电容中点电流平均值的直流侧电压偏置补偿器。相关的仿真与实验结果均证明了该SVPWM优化策略的可行性和有效性。

Focusing on the problem of the DC capacitor voltage change in the three-phase four-switch shunt active power filter （TFSAPF）,the circuit topology structures of different switching modes are analyzed, and the summary of the reasons causing the DC capacitor voltage to change is given.The SVPWM optimizational strategy is given which chooses different equivalent zero vector to balance DC capacitors voltage by detecting the differential voltage and the direction of the current of capacitors.In order to solve the neutral point voltage floating, capacitor voltage compensator is designed based on detecting the average value of the neutral point current.Simulations and experiments are com- pleted to verify the feasibility and effectiveness of the proposed SVPWM optimizational strategy.