Transient Overvoltage Suppression Strategy Considering Reactive Power Dynamics of New Energy Units

To address the transient overvoltage (TOV) issue caused by excess new energy (NE) reactive power under commutation failure (CF) faults, the strategy of suppressing TOV has been proposed from two aspects: curbing excess reactive power and exploiting reactive power absorption potential. First, the relationship between excess NE reactive power and TOV at the rectifier bus is analyzed, with a focus on influence of voltage detection delay on AC voltage from the perspective of excess reactive power in renewable converters. Subsequently, a control strategy of compensating delay is proposed to counteract the delay effects. Building on this, a nonlinear reactive current-voltage curve is designed to simultaneously achieve steady-state voltage oscillation suppression and transient reactive power fast response, effectively mitigating TOV in the sending end network during CF. Finally, simulation results demonstrate that the improved NE control strategy significantly suppresses TOV in the sending end network.