Investigating the frequency fault ride through capability of solar photovoltaic system: Replacing battery via virtual inertia reserve

The low voltage ride through (LVRT) capability is an important aspect of the microgrid system, dominated by renewable energy sources (RES). Earlier studies investigate the LVRT capabilities of microgrids but ignore their frequency stability during and after the fault scenario. This paper fills this gap by investigating the frequency fault ride through (FFRT) capability of photovoltaic (PV) based microgrid model and suggests a novel PI-based virtual damping (PIVD) controller for enhancing the dynamic performance. This controller tracks the frequency error and de-loads the solar power in the same proportion. This de-loading creates useful virtual inertia reserve (VIR), which replaces the role of battery storage by stabilizing the grid during the contingency period. To validate the effectiveness, a microgrid assisted with the PIVD controller is simulated in MATLAB and its frequency performance is compared with pre-existing conventional and ESS models. The comparative results confirm that the proposed model is capable of riding through the severe fault scenario, with the least possible frequency deviation.

Automated summary

This study investigates the frequency fault ride through capability of a photovoltaic-based microgrid model and proposes a novel PI-based virtual damping controller to enhance its dynamic performance. The controller tracks frequency error and adjusts solar power output, creating a virtual inertia reserve to improve grid stability during emergencies. Simulation results show that the proposed model can effectively ride through severe fault scenarios with minimal frequency deviation.