Cascading collapse of a large-scale mixed source microgrid caused by fast-acting inverter-based distributed energy resources

Power electronics-based distributed energy resources (DERs) are being increasingly deployed for achieving high energy efficiency, power quality, and flexibility of power system operation and controls. They facilitate access to various kinds of energy sources including renewables, fuel cells, microturbines, variable speed engine-generator sets, etc. However, recent tests carried out at the Consortium of Electric Reliability Technology Solutions (CERTS) Microgrid have indicated that their deployment in the mixed source microgrid can cause a cascading collapse during extreme events. Simulation models of two types of DERs are developed in PSCAD/EMTDC software and validated with the experimental test results. The validated models are used to study a cascading collapse problem in a large-scale mixed source microgrid on the benchmark IEEE 33-bus test system. This paper evaluates three alternative techniques to prevent the cascading collapse in the large-scale microgrid caused by fast-acting power electronics-based DERs.