Ground fault analysis in a micro grid scenario

Microgrids are based on the same grounding schemes generally adopted in the low voltage radial distribution grids. Unlike traditional distribution grids, in islanded microgrids the neutral grounding becomes a complex problem due to different operating configurations.

 All the electrical devices connected to the microgrid must be modeled to guarantee the access to the neutral point and their models have to be easy to include in the whole microgrid model. 

The Voltage Behind Reactance model is here introduced to meet these requirements in the synchronous machine modeling, and the complete model of a benchmark islanded microgrid is developed. The line-to-ground fault transient under different neutral grounding configuration are analyzed.

Index Terms: Microgrid, fault analysis, asymmetric failure.