Performance tolerant control of shunt active power filter under unbalanced nonlinear load

A robust control strategy is proposed and used for a digitally controlled shunt active power filter (SAPF). The SAPF is designed to minimize the real-time computation requirements by resizing the different computational element in low frequency control groups with a balanced or unbalanced load. An unbalanced load tolerant control is tested and evaluated for active power filter structure. We have taken into account the power losses of the insulated gate bipolar transistor (IGBT) model in order to optimize the energy transfer. The instantaneous modified active and reactive power (p-q) method for harmonic detection based on phase locked loop (PLL) control strategy has been used to control the SAPF system. This control strategy has been simulated by using Matlab/Simulink.