Analysis of Modified Shunt Active Power Filter Based on One Cycle Control

Shunt active power filters (SAPF) are used to compensate for the distorted currents of nonlinear loads. SAPF consists of a grid-connected inverter negating harmonic and reactive currents of nonlinear loads. Some previous researchers have proposed one cycle control (OCC)-based SAPF which is simpler to implement and requires only grid-side current sensing. Here, a modified OCC-based SAPF is proposed and its performance is compared for single-phase loads. For control of inverter switches, carrier and modulating waveforms are compared to generate PWM pulses. In existing OCC-based methods, a ramp waveform of variable magnitude is used as a carrier, and grid current is used as a modulating wave. However, in the proposed method, a constant triangular wave is used as carrier and modulating wave is scaled magnitude of grid current. The proposed method is simpler to implement. The paper compares the simulation results of existing SAPF with the proposed one.