Harmonic distortion degradation and filter optimization based on sensitivity studies with considering resonance issue

Abstract

Voltage distortions are characterized by the harmonic spectrum of the nonlinear load (NLL) and harmonic impedance of the whole system. On one hand, the harmonic impedance is at the peak value when the frequency is at the resonance point, which leads to serious voltage distortions. On the other hand, harmonic distortions will be excited from excessive harmonic emission without resonance. In order to address the above causes, shifting the resonance frequency sensitivity (RFS) and the critical individual harmonic voltage distortion (IHDV) sensitivity (IHDS) indices are presented here to control the critical IHDV and total harmonic voltage distortion (THDV). The main idea is to find and adjust the most sensitive network parameter against these sensitivity indices until the harmonic distortion reaches the required value. A three‐bus test system and the IEEE 14‐bus system are used to verify the proposed method. Comparison of the results shows that these indices complement each other for solving the harmonics problems with or without harmonic resonance. The sensitivity‐based methods can be effective for system optimization and filter design by considering harmonic resonance. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.