Power Quality Control Strategy of Islanding Microgrid Under Distortedand Unbalanced Conditions

摘要

This paper presents a novel power quality control strategy for islanding microgrid contains multiple DG unitsunder both distorted and unbalanced conditions. Actually the power quality of microgrid bus and the point of commoncoupling (PCC) are the main concerns due to the determination of high-quality power energy to the main grid and sensitiveloads connected to microgrid bus. To tackle this problem, three control schemes based on PIR cascaded structure forDG units are developed to realize different control objectives. In these categories, the fundamental voltage is regulated byconventional PI controller to ensure direct voltage support and smooth operation mode transition while the harmonics orunbalanced variables are compensated with resonates controller in synchronous reference frame without sequential sequencedecomposition. The proposed power quality control strategy that comprehensively utilization of these controlschemes can satisfy power quality requirements of islanding microgrid, which is confirmed by simulation results consideringboth unbalance and distortion.