An advanced control method of inverters in Microgrid

In this paper, it is discussed from the aspects of the operation requirements in Microgrid and the control methods in power system, focusing on the idea of how to make the inverter imitate the output characteristics of the synchronous generator. The fundamental difference between Microgrid and the power grid lies in the hardware interface, one is the inverter, the other is synchronous generator. Analyzing the mathematical model of synchronous generator, referring to the typical second-order model, combining the characteristics of inverter itself, the control algorithm is derived, the inverter control system with synchronous generator output features is built, which can fully meet the requirements of the Microgrid environment. Comparing to the working principle of the primary frequency regulator, the secondary frequency regulator, the voltage regulator and other mature theory, the frequency and voltage control strategies of the system are fully explained. Based on the proposed control algorithm and the controllers, using the tool of simulation, the inverter and its controller simulation model are built. Compare to the output characteristics of inverter and synchronous generators, all simulation results verify that the algorithm and the voltage and frequency regulator are correct, and it also prove that the proposed inverter model can represent the output characteristics of the synchronous generator.