Shunt Hybrid Active Filter By Using Cascaded H Bridge Multilevel Inverter

Abstract

The shunt active power filter is one of the major solutions for harmonics current in power distribution networks. These papers presents the hybrid topology for reducing the rating of the voltage source inverter (VSI) of shunt active power filter and also provide the simultaneous harmonic current mitigation and reactive power compensation. The hybrid topology developed by using convectional shunt active filter in series with capacitor and cascade H bridge multilevel inverter (CHB MLI). Two-level voltage source inverter provides harmonic compensation and cascade H bridge multilevel inverter provides reactive power compensation to the system. The switching signal for MLI is generated by using level shifted PWM and bipolar sinusoidal PWM was used for two level inverter (VSI). Compared to conventional shunt filter, the DC link voltage is shared by dc link capacitor of VSI, DC link capacitor of MLI and series capacitor because in the system the all capacitors are connected in series. So rating of switches is effectively reduced. Hybrid active shunt filter is modeled and the response is obtained through MATLAB SIMULINK toolbox.