直流近区系统故障下的暂态电压特性分析及支撑策略研究  

Research on transient voltage characteristics and support strategy under a fault occurred in the near-zone of HVDC sending system

作　　者：秦艳辉 尹纯亚 段青熙 马星 QIN Yanhui;YIN Chunya;DUAN Qingxi;MA Xing(School of Electrical Engineering,Southeast University,Nanjing 210096,China;State Grid Xinjiang Electric Power Co.,Ltd.Research Institute,Urumqi 830011,China;School of Electrical Engineering,Xinjiang University,Urumqi 830017,China)

机构地区：[1]东南大学电气工程学院,江苏南京210096 [2]国网新疆电力有限公司电力科学研究院,新疆乌鲁木齐830011 [3]新疆大学电气工程学院,新疆乌鲁木齐830017

出　　处：《电力系统保护与控制》2023年第17期169-177,共9页Power System Protection and Control

基　　金：新疆维吾尔自治区自然科学基金项目资助(2022D01C363);新疆维吾尔自治区教育厅项目资助(XJEDU2022P019)。

摘　　要：针对直流近区域交流系统故障与特高压直流交互作用下的暂态电压机理尚不明确的问题,在深入分析交直流系统无功功率交互作用的基础上,明确了影响暂态电压的主导因素。考虑故障持续时间及故障严重程度,建立了换流母线暂态电压计算表达式,揭示了不同故障严重程度及短路比下整流器无功功率消耗对暂态电压的影响机理。基于此,推导建立了直流电流指令值计算表达式,并提出了整流器控制优化策略,实现了直流系统对暂态电压的主动支撑。最后,基于PSCAD与CIGRE HVDC的仿真结果验证了理论分析的正确性与暂态电压支撑策略的有效性。In view of the unclear mechanism of transient voltage caused by a fault occurred in the near area of HVDC sending system with the interaction of AC and UHVDC,based on the in-depth analysis of the interaction of reactive power AC and DC systems,the dominant factors affecting transient voltage are identified.Considering the fault duration and severity,the expression for calculating the transient voltage of the commutation bus is established,revealing the mechanism of the influence of reactive power consumption of the rectifier on transient voltage under different fault severity and short-circuit ratio.Based on this,an expression for calculating the DC current command value is derived and established,and an optimization strategy for rectifier control is proposed to achieve active support of the DC system for transient voltage.Finally,the simulation results based on PSCAD and CIGRE HVDC have verified the correctness of the theoretical analysis and the effectiveness of the transient voltage support strategy.

关 键 词：高压直流输电 暂态电压 直流控制 交互作用机理 

分 类 号：TM721.1[电气工程—电力系统及自动化]