基于负序电压前馈的改进型柔性直流输电系统有功功率控制策略

Improved active power control strategy of voltage source converter based high voltage direct current transmission system based on negative sequence voltage feedforward

柔性直流输电技术凭借其独特的性能优势被广泛应用于直流输电工程。本文针对在故障期间两端柔性直流输电系统交流侧出现的负序电压分量,提出一种基于负序电压前馈的改进型柔性直流输电系统有功功率控制策略,用于抑制系统在故障期间出现的直流电压波动并滤除流过平波电抗器的负序电流分量,以增强系统的稳定性。仿真结果表明,所提出的改进型控制策略可以在故障时稳定直流电压并减轻故障对交流电网的影响。

Voltage source converter based high voltage direct current transmission(VSC-HVDC)technology is widely used in DC transmission applications due to its unique performance advantages.In case of the negative sequence voltage component in the AC side of the VSC-HVDC system during the fault,an improved active power control strategy based on negative sequence voltage feedforward is proposed to suppress the DC voltage fluctuation and filter out the negative sequence current component flowing through the smoothing reactor in order to enhance the anti-instability ability of the system.The simulation results show that the improved active power control strategy can suppress the DC voltage fluctuation and reduce the impact on AC power grid under fault.