Wireless parallel control of three-phase inverters based on virtual synchronous generator theory

In this paper, virtual synchronous generator (VSG) theory is investigated and utilized to control parallel inverters in a micro-grid, which is capable of sharing the local loads without communication lines. The mathematical model of VSG is built to describe the electromagnetic and mechanical characteristics of a synchronous generator. To make the model suitable for parallel inverters application, droop control is embedded to ensure the active and reactive power regulations. A small signal model is built to analyze dynamic and steady property of inverters. As a result, different VSGs with different parameters can share the power of local loads according to their capacities, and can meet the performance of different response time. At last, the validity and effectiveness of the proposed approach are verified by the simulated results using PSCAD/EMTDC.