Design and Implementation of Three Phase Three Level Shunt Active Power Filter for Harmonic Reduction

This paper presents simulation and hardware implementation of Three Phase Three Level Shunt Active Power Filter to mitigate the supply current harmonics and inject the required reactive power to non-linear loads. The standard operating principle of shunt active filter is to inject current harmonics into the point of common coupling. This scheme consists of three phase three level diode clamped multilevel inverter which can be used to reduce the source current harmonics. The proposed pulse width modulation (PWM) scheme generates the inverter leg switching times, from the sampled reference phase voltage amplitudes and centres the switching times for the middle vectors, in a sampling interval, as in the case of conventional space vector PWM (SVPWM). Effectiveness of the system is verified by the experimental results obtained from the prototype model.