Multi-Objective Optimization Based Approaches for Active Power Filter Design- A Comparison

This paper introduces an optimal active power filter design method to compensate simultaneously current harmonics and reactive power of a nonlinear load. The power filter consists of a passive RL low-pass filter placed in series with the load and a pure active filter which has RL elements connected in series with insulated gate bipolar transistors (IGBT) based voltage source converter. The filter is supposed to inject a current into the connection node of the load and grid in order to eliminate current harmonics and its imaginary current. The voltage source converter is placed in a hysteresis feedback control loop to generate the reference current. The band width and output amplitude of the hysteresis controller are optimized with inductance of RL filters. In solving the optimization problem, three objective functions are considered which include minimizing current total harmonic distortion (THD), maximizing power factor and minimizing the IGBT bridge current. The four optimization methods applied are the goal attainment, max ordering, non-dominated sorting genetic algorithm-II and strength Pareto evolutionary algorithm 2 (SPEA2) methods. The results of the four optimization methods are compared and it is shown that the SPEA2 method gives the best performance in terms of minimizing current THD and maximizing the power factor. Streszczenie. Przedstawiono metody optymalizacji projektowania aktywnych filtrów mocy umożliwiające kompensację prądów harmonicznych i mocy biernej przy obciążeniu nieliniowym. Analizowany filtr składa się z pasywnego filtru dolnoprzepustowego RL połączonego szeregowo z obciążeniem i filtrem aktywnym. Filtr aktywny mam elementy R:L dołączane z wykorzystaniem tranzystora IGBT. (Wieloparametryczna optymalizacja projektowania aktywnych filtrów mocy – porównanie metod)