Enhanced VSG-Based Control for Parallel Grid-Forming Converters in an Autonomous Microgrid

This paper introduces a virtual synchronous gen-erator (VSG)-based control scheme with governing action tai-lored for grid-forming converters within autonomous micro-grids (MGs). A comparative analysis is conducted between conventional droop control and the proposed VSG control. In autonomous mode, conventional droop control exhibits limited inertia and damping, leading to sharp changes in converter output frequency during load disturbances that may violate rate of change of frequency (ROCOF) regulations. In contrast, the proposed VSG controller is engineered to deliver superior performance. By incorporating governing action, the proposed VSG-based control introduces virtual inertia, effectively minimizing power oscillations and reducing settling time in autonomous MGs. This approach ensures smoother frequency transitions and enhances overall MG stability. Unlike conventional droop control, which employs a proportional controller with a low-pass filter, the VSG controller dynamically adapts its active power control loop to disturbances, closely emulating the behaviour of synchronous generators. Comprehensive simulations conducted in MATLAB Simulink R2023b validate the efficacy of the proposed VSG-based control. These results affirm that VSG-based control surpasses conventional droop control in managing frequency stability and fortifying the resilience of autonomous MGs.