Comparison and Selection of Grid-Tied Inverter Models for Accurate and Efficient EMT Simulations

This article compares five modeling methods of grid-tied inverters for the electromagnetic transient simulation of power system, clarifies their differences, and discusses the suitable model for each simulation purpose. The comparison was made under the same conditions between the conventional switching model, and four simplified models—voltage interpolation, average-value, controlled current-injection, and simplified current-injection model. The comparison of the simulated waveforms clarifies the behaviors that can be simulated and cannot be simulated by each simplified model. The comparison of the computing time reveals the significant decrease of the computing time by selecting the proper simplified modeling method. Based on these comparisons, this article discusses the selection of the modeling methods for each simulation purpose to perform simulations accurately and efficiently.