A New Multilevel Inverter Based Parallel Active Power Filter

Abstract

Developments in the field of power electronics have increased the use of non-linear loads. The increase in the use of these loads causes power quality to decrease and problems to appear in transmission and distribution systems. The adverse effect of passive harmonic filters and the up-growing use of modern sensitive loads in the production process have made active power filters an important area of interest in eliminating current and voltage harmonics. In this study, a multilevel inverter topology for parallel active power filter applications has been proposed. The principle of operation for the proposed multilevel inverter topology is explained in detail. The harmonic components of the grid current which has a high total harmonic distortion (THD) value, are eliminated by the proposed multilevel inverter providing a reduced number of switching elements. The generation of switching signals for parallel active power filter application is also expressed with generalized formulas. All required operating states of multilevel inverter topology are given in detail to obtain reference filter current with harmonic components. In addition, the simulation studies carried out for different number of level modules and different values of harmonic distortion are presented. The obtained results show that the proposed multilevel inverter topology is suitable for parallel active power filter applications.