Application of VIPWM technique on three phase Shunt Active Filters

This paper presents a Shunt Active Filter (SAF) based on the Variable Index Pulse Width Modulation (VIPWM) approach. In the proposed method of Pulse Width Modulation (PWM), the triangular wave is derived by integration of the reference signals. This method introduces two basic advantages, the first one is that the triangular signal contains the information of the signal to be obtained in output and the second advantages is that its amplitude is varied in proportion to the amplitude of the reference signal. Therefore, in this PWM method, the modulation index is varied according to the variation of the reference signal, so it is termed as Variable Index Pulse Width Modulation. In order to demonstrate the validity of the proposed method, the obtained simulation results are compared with results of the Space Vector Modulation (SVM) approach. Furthermore, it is shown that in the case of non-sinusoidal voltages, the SAF with the proposed control strategy can provide the filtering action. This method is quite easy to implement and requires lower circuitry. The results show that the proposed method can satisfy the IEEE-519 standard regarding the reduction of harmonics.