Coordinated Adaptive Control Strategy of Rotational Inertia and Damping Coefficient for Virtual Synchronous Generator

Abstract

The Virtual Synchronous Generator (VSG) adds rotational inertia and damping co-efficient to traditional inverter control, which enhances the anti-interference ability of the microgrid (MG). However, the adding segment negatively impacts the response speed of the system. Hence, a coordinated adaptive control strategy of rotational inertia and damping coefficient for VSG is proposed. Firstly, this paper analyzes the effects of rotational inertia and damping coefficient on the power and frequency of an islanded MG. Secondly, it is analyzed that the deviation and rate of change of angular velocity when the synchronous generator suffers load fluctuations. Based on the above analysis, a coordinated adaptive control strategy of rotational inertia and damping coefficient for VSG is proposed. The strategy recognizes the change of frequency and enables the rotational inertia and damping coefficients to be adaptively adjusted in concert with the frequency changes. It achieves the reduction of frequency overshoot while improving the response speed of the system. Finally, the effectiveness of the presented control strategy has been successfully demonstrated with the simulation results in MATLAB/Simulink.