Research on Adaptive VSG Control Strategy Based on Inertia and Damping

Abstract

Virtual synchronous generator (VSG) simulates the working principle of synchronous motor, and applies the moment of inertia and damping coefficient in the synchronous motor control technology to the control of grid-connected inverter in its control strategy, which can improve the frequency response characteristics of the system and enhances the anti-interference capability of microgrid, but the ability to dynamically adjust decreases. In this paper, we propose a VSG inertia and damping adaptive control strategy, which can not only improve the power and frequency adjustment ability of the system, but also make the frequency response of the system better. Firstly, establish a mathematical model of VSG according to the working principle, and analyze the impact of inertia and damping on system performance on this basis, then analyze the feasibility of adaptive changes of these two parameters. Secondly, the power-frequency transient process of VSG is analyzed according to the power-angle characteristic curve of synchronous generator, and the design calculation principles are obtained according to the changes of these parameters. Finally, PSCAD/EMTDC simulation proves that the control strategy proposed in this paper can achieve the expected effect.