一种三相四开关有源电力滤波器SVPWM方法

SVPWM of Three-phase Four-switch Active Power Filter

三相四开关逆变器具有结构简单、硬件成本低的特点,且可作为三相六开关逆变器的容错拓扑结构。但三相四开关逆变器只有4个长度不完全相等的有效电压矢量,且无零矢量。针对上述问题,提出一种三相四开关有源电力滤波器(APF)的空间矢量脉宽调制(SVPWM)方法。该方法首先利用2个空间位置相邻的有效电压矢量合成参考电压矢量;并利用2个方向相反的有效电压矢量合成零矢量,为合理选择合成零矢量所需的电压矢量,对电压矢量的扇区进行重新划分。该方法可应用于APF的容错控制,从而提高其工作可靠性。仿真和实验结果证明了该方法有助于提高谐波补偿的精度。

The three-phase four-switch inverter has the characteristics of simple structure and low hardware cost, which also could be used as a fault-tolerant topology of three-phase six-switch inverter.However,there are only four active voltage space vectors that the amplitudes are not equal,and no zero vector in the three-phase four-switch inverter.In response, a space vector pulse width modulation （SVPWM） strategy is proposed for the three-phase four-switch active power filter（APF）.Firstly, the synthetic reference voltage vector by two adjacent active voltage space vectors and the sy- nthesis zero vector are got by two active voltage vector with equal amplitude and opposite direction.In order to choose the right space voltage vectors to synthesize the zero vector, the sectors of the voltage space vectors are redivided.This method can be applied into the fault-tolerant control for APF, which can be implemented to enhance operational relia- bility of APF.The effectiveness of the proposed method is validated by results of simulation and experiment.