Low Voltage Ride through Enhancement Using Grey Wolf Optimizer to Reduce Overshoot Current in the Grid-Connected PV System

Abstract

In today's world, the DG should not be disconnected in the event of a power outage but should instead remain linked to the grid and supported by reactive power. This can be accomplished by implementing the low voltage ride through (LVRT) with a proportional integral (PI) controller. As a result, the voltage profile can be enhanced. The PI controller, on the other hand, has drawbacks in that setting the gain takes a long time and results in an overshoot current on the grid, which could trigger the protection relay. To address this issue, this paper proposes employing a grey-wolf optimizer (GWO) to enhance the LVRT in a 5 MW three-phase grid-connected PV system. A MATLAB simulation was carried out then under a three-phase fault and load disturbance to verify the efficiency. It is found that, even with a 70% voltage sag, the PV system can remain connected to the electrical grid while minimising overshoot current on the grid side.