含STATCOM的LCC-HVDC系统的动态模型及小信号稳定性研究

Dynamic Model and Small-signal Analysis of LCC-HVDC System With STATCOM at the Inverter Busbar

该文建立含静止同步补偿器（static synchronous compensator,STATCOM）的电网换相换流器高压直流输电（line commutated converter based high voltage direct current,LCC-HVDC）系统的小信号模型,通过与详细电磁暂态模型的对比,对其准确性进行验证。基于该模型,研究锁相环（phase-locked loop,PLL）、LCC-HVDC与STATCOM控制系统参数对整个系统的小信号稳定性与动态性能的影响,并得到不同控制系统参数的可行域。最后分析锁相环（phaselocked loop,PLL）、LCC-HVDC与STATCOM控制系统之间的相互耦合作用,结果表明该耦合作用使得不同控制系统的参数可行域相互约束,为系统设计和参数选择提供有价值的参考。

This paper developed a linearized small-signal dynamic model of a line-commutated-converter based high voltage direct current（LCC-HVDC） system with static synchronous compensator（STATCOM） at the inverter busbar, and validated its accuracy by comparing time-domain responses from small-signal model and PSCAD-based simulation results. Based on the small signal model, this paper investigated the impact of phase-locked loop（PLL） gains, the control parameters of LCC-HVDC and STATCOM on the system small-signal stability by eigen-analysis and participation factor methods, and reveals the feasible region of the different control parameters. Finally, this paper analyzed the coupling effect among PLL, LCC-HVDC control system and STATCOM control system. The results show that the coupling effects restrain the feasible regains of the different control parameters, and this paper can provide valuable reference for the system design and control parameter selection.