基于频率同步控制的VSC-HVDC在弱交流系统下的动态特性研究  

Dynamics Investigation of VSC-HVDC With Frequency Based Synchronization Control Under Weak AC Grid Condition

作　　者：郭春义 宁琳如 刘炜 赵成勇 刘栋 

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市昌平区102206 [2]先进输电技术国家重点实验室(全球能源互联网研究院),北京市昌平区102209

出　　处：《中国电机工程学报》2017年第15期4344-4354,共11页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51507060);先进输电技术国家重点实验室开放课题资助;中央高校基本科研业务费专项资金资助(2016MS07)~~

摘　　要：该文研究适用于电压源型换流器高压直流输电(voltage source converter based HVDC,VSC-HVDC)连接弱交流系统的频率同步控制方法(frequency based synchronization control,FSC)对系统运行特性的影响。建立采用FSC控制的VSC-HVDC连接弱受端交流系统时的小信号模型,并将其与PSCAD/EMTDC中的电磁暂态仿真结果进行对比,验证了小信号模型的正确性。然后,基于小信号模型分析FSC控制中功率阻尼系数和功率同步系数对VSC系统小信号稳定性的影响。最后,针对交流系统频率变化、负荷阶跃和三相短路故障3种暂态运行工况,研究FSC控制下VSC系统的动态特性。结果表明,FSC控制不仅可提高VSC连接弱交流系统时的小信号稳定性,而且使系统具有良好的频率跟踪响应和过电流限制能力。This paper investigated the impact of frequency-based synchronization control （FSC） approach on Voltage Source Converter based HVDC （VSC-HVDC） under weak AC grid condition. The small-signal model of VSC-HVDC system under FSC was developed, and the dynamic performances comparisons between small-signal analysis and detailed electromagnetic transient simulation in PSCAD/EMTDC were conducted. The results validate the small-signal model. Then, based on this model, the paper analyzed the impact of power-synchronization and damping coefficients of FSC on small-signal stability of VSC-HVDC. Finally, the dynamic performances were investigated under three transient operating conditions, i.e. frequency variation, load step-change and three-phase to ground fault. The conclusions can be obtained that the adopted FSC approach enhances the small-signal stability, and presents favorable frequency- tracking response and over-current limiting ability.

关 键 词：电压源型换流器 弱交流系统 频率同步控制 动态特性 

分 类 号：TM731[电气工程—电力系统及自动化]