摘要
多馈入直流系统中,某一线路发生故障经交流电网传播至直流系统换流母线处,可能会引发多直流换相失败。为对多馈入直流换相失败风险程度进行有效评估,该文构建多馈入直流系统换相安全综合裕量指标,并基于此提出同步调相机布点选取方法。首先,考虑同步调相机安装位置与功率—电压灵敏度,推导多馈入直流系统电压交互作用因子计算方法;然后,对三相金属性故障时仍不引发直流换相失败的节点进行识别,并以上述节点故障时引发的单一直流换流母线不同电压跌落与换相失败临界电压跌落的距离之和,作为该直流的换相安全裕量(commutation security margin,CSM),进一步考虑不同直流容量及相互作用程度,构建多馈入直流换相安全综合裕量(synthetical CSM,SCSM)评估方法;最后,提出同步调相机布点选取方法。基于PSCAD/EMTDC中的改进IEEE39节点多馈入直流系统,仿真研究三相和单相接地故障下多馈入直流系统的换相失败风险程度,结果表明,所提出的同步调相机布点选取方法可以有效提升多馈入直流的换相安全综合裕量,从而降低换相失败风险,可为实际工程中同步调相机等无功补偿设备的布点选取提供指导。
In a multi-infeed DC system,if a fault occurs on a certain line and propagates through the AC power grid to the inverter buses of the DC systems,it may lead to commutation failure in multiple DC systems.To effectively assess the risk of commutation failure in multi-infeed DC systems,this paper constructs a synthetical commutation security margin(SCSM)index,and proposes a method for synchronous condenser placement based on this.Firstly,considering the installation location and power voltage sensitivity of synchronous condensers,the interaction factors of voltage in multi-infeed DC systems are derived.Secondly,under different nodes’grounding faults in the AC system,the sum of the distances between the voltage drops of the single DC inverter buses and the critical voltage drop for commutation failure is taken as the commutation security margin(CSM)of the LCC-HVDC system.Furthermore,taking into account the different DC capacities and interaction degrees,a comprehensive assessment method for the CSM of multi-infeed LCC-HVDC systems,termed synthetical CSM(SCSM),is constructed.Finally,based on this,a method for selecting locations of synchronous condensers is proposed.Using a modified IEEE 39-bus system in PSCAD/EMTDC,simulations are conducted to study commutation failure risk level in multi-infeed DC systems under three-phase and single-phase ground faults.The results demonstrate that the proposed method for synchronous condenser placement can effectively enhance the SCSM and reduce the commutation failure risk in multi-infeed DC systems,thereby providing guidance for the deployment of reactive power compensation devices such as synchronous condensers in practical engineering.
作者
肖嘉辰
郭春义
丁银香
XIAO Jiachen;GUO Chunyi;DING Yinxiang(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,China)
出处
《中国电机工程学报》
北大核心
2025年第22期8796-8806,I0011,共12页
PROCEEDINGS OF THE CHINESE SOCIETY FOR ELECTRICAL ENGINEERING
基金
国家重点研发计划项目(2021YFB2400900)。
关键词
多馈入直流系统
换相失败
换相安全综合裕量
同步调相机
布点选取
multi-infeed HVDC systems
commutation failure
synthetical commutation security margin
synchronous condenser
deployment selection
