Complex blind source separation based harmonic contribution assessment

Harmonic contribution assessment is the precondition of harmonic responsibility-sharing and mitigating and its difficulty lies in real-time assessment of harmonic impedance. In order to solve this problem, this paper proposed a complex blind source separation (CBSS) based harmonic contribution assessment method. Use linear filter to abstract fast changing components from measuring data at the point of common coupling (PCC) and establish a CBSS based harmonic contribution assessment model; use complex maximization of non-Gaussianity (CMN) to assess demixing matrix, impedance matrix, and harmonic sources and the process of harmonic contribution assessment is studied in detail on this basis. The proposed method is validated by simulation, comparing with current methods, and the results prove that the proposed method can separate harmonic contribution directly with measuring data and it is suitable for resonance and non-resonance cases.

I. Introduction

With more and more nonlinear loads and distributed generations integrated to power grids, harmonic has become a significant problem resulting in huge economic losses and customer complaints. In order to share harmonic responsibility, harmonic contribution has received great attention [1]–[3]. The harmonic voltage and current contributions at the point of common coupling (PCC) depend on the size of the harmonic sources and harmonic impedances on utility and customer sides which are difficult to determine. In order to avoid the difficulty caused by the estimation of harmonic impedance, the direct separation of the harmonic contribution from the recorded data of harmonic voltage and current at PCC may be one of hopeful choices.