Comparison and selection of high-voltage large-capacity D-STATCOM main circuit

In view of analysis and comparison of present high-voltage large-capacity D-STATCOM circuit structure, especially advantages and disadvantages of Δ-cascaded structure and Y-cascaded structure, then it proposes and describes a Y-cascaded structure, the link of which is composed of two back-to-back H converters. Current compensation algorithm based on coordinate αβ conversion, fault links bypass tolerance, and its correlative CPS-SPWM are proposed respectively, the experimental results of 1.14kV/100kVA prototype testify the validity and the effectivity of the proposed structure and algorithm.