A two-phase three-wire quasi-Z-source based railway power quality compensator for AC rail networks

Power quality (PQ) problems of AC railway systems have become a major obstacle so that over the years different compensation methods have been introduced to dominate them. Railway Power Quality Compensator (RPQC) is one of the effective strategies which had been presented with different structures and compensation methods. However, these conditioners basically have high capacity and also high potential to be exposed to destruction due to the shoot-through switching. In this paper a quasi Z-source based Railway Power Quality Compensator (qZRPQC) is proposed to improve mentioned problems. The proposed configuration is based on two-phase, three-wire converter composed of two step-down transformers connected to the two adjacent sections of the traction power substation. Despite having the all features of traditional RPQC, the proposed configuration can decrease the rating of the converter and increase the efficiency and reliability. In order to verify the performance and effectiveness of the proposed strategy the precise simulation results have been provided.