A differential search algorithm application for solving harmonic estimation problems

This paper presents an optimization approach based differential search algorithm (DSA) for amplitude and phase estimation of time varying power signal in electrical power systems. Proposed method has been tested for two well-known literature problems that include fundamental, sub- and inter-harmonic estimation cases. The performance of the suggested DSA method has been compared with those of the Genetic Algorithm-Least Square (GA-LS), Particle swarm optimization with passive congregation least square (PSOPC-LS), Bacterial foraging optimization (BFO), Fuzzy bacterial foraging-least square (F-BFO-LS) and Bacterial foraging optimization-recursive least square (BFO-RLS). The results show that the proposed DSA method has an efficient, fast and accurate estimation behavior among previously reported ones in the case of time varying harmonic power signals. In addition, the estimated amplitude and phase values using DSA method can provide possibility to design suitable harmonic reducing filter for improving power quality.

I. Introduction

Recent years, power electronic switching elements and industrial devices have been extensively used by people in inside and outside applications. So, power quality in the aforementioned systems has attracted much attention by researcher and practitioners. The most studied negative effect in power systems is harmonic pollution and it is caused by high level harmonics that can be basically modeled as unwanted spectral ingredients of disrupted electrical waveforms and their frequencies appear as integer multiples of fundamental frequencies. Harmonics have disruptive effect on electrical systems such as electrical losses, equipment heating and damaging, failure in the protection systems, data losses in power line communication systems and faulting in appliances [1], [2]. Because of these troubles, the problem of harmonic estimation has become an important issue in power electronics [3].