Direct vs. Indirect Control Schemes for Grid-Forming Inverters – Unveiling a Performance Comparison in a Microgrid

This article provides insights into the dynamic performance of indirect and direct control strategies for grid-forming (GFM) inverters. The method inverters utilizes three cascaded stages to produce reference signal sent PWM generator. However, has only one stage. consists outer loop, which controls power, middle requlates voltage, inner output current. does not require loops. compares sensitivity both methods under various conditions, including static, inductive loads, by adjusting controller gain parameters. A virtual reactance inrush current mitigation technique is implemented with provide momentary over caused loads. incorporates a feedforward known as outperform in presence experimentally compared, outperforms method. Experimental analyses are performed laboratory-scaled microgrid supplied 208V, 5kVA SiC inverter, 10kVA Si-based inverter compare different test scenarios, outcomes presented this article.