含同步调相机的直流受端换流站全工况下多模式协调控制策略

Multi-Mode Coordinated Control Strategy for DC Receiving Converter Station with Synchronous Condenser under Full Operating Conditions

针对当前缺乏同步调相机(SC)与直流控保系统和换流站内无功补偿小组之间协调控制的研究,该文介绍了电网换相换流器的高压直流输电系统(LCC-HVDC)受端换流站准稳态模型,推导出SC端电压与励磁电流If的关系式,提出一种含SC的直流受端换流站全工况下多模式协调控制策略。策略包括防止暂态电压超限的无功小组投切控制模式、大幅增加自动电压控制(AVC)指令调节范围的AVC模式和故障下抑制换相失败发生的暂态控制模式。根据实际工程参数,在PSCAD中建立了祁韶±800kV特高压直流输电系统模型,并在投切滤波器、AVC下发指令及交流故障等多工况下进行仿真验证,结果表明所提策略有效改善了含SC的受端系统运行特性,提高了电压稳定性。

Aiming at the lack of research on the cooperation between synchronous condenser(SC)and DC control system and reactive power group in converter station,the quasi-steady state model of the line commutated converter-high voltage direct current(LCC-HVDC)receiving converter station is introduced,and the relationship between the SC terminal voltage and the excitation current If is derived,a multi-mode coordinated control strategy for DC receiving end with SC under full conditions is proposed.Which includes a reactive group switching control mode that prevents transient voltage exceed the limit,an automatic voltage control(AVC)mode that increases the AVC command adjustment range,and a transient control mode that suppresses the occurrence of commutation failure under system fault.The model of Qishao±800kV UHVDC transmission system is established in PSCAD,and the simulation is verified under the multi-conditions. The results show that the proposed strategy effectively improvesthe operating characteristics of the SC-containing receiving system.