Solid state transformer specification via feeder modeling and simulation

This paper discusses the design specification method of a 1MVA, 13.8kV/480V solid state transformer (SST, also called a Transformerless Intelligent Power Substation - TIPS). A simplified IEEE 34 bus test feeder was used in the study and a dynamic model of the TIPS was developed and incorporated into the feeder model. Feeder circuit stability issues when TIPS connects at a weak system point were observed and mitigation method studied. The overloading capability of TIPS and the overvoltage protection requirements of TIPS were also investigated.