【摘要】 可靠、精准地识别特高压直流输电系统故障是区内、外保护动作的基础,对整个直流输电系统安全可靠运行具有决定性意义。基于贝瑞隆分布参数模型,以方向电流法为基础引入暂态能量偏离度(暂态值与正常值之比)共同构成故障识别判据,提出一种可准确辨识特高压直流输电整流侧出口故障、直流线路故障和逆变侧出口故障的方法。该识别方法对直流线路通信通道要求低、耐过渡电阻能力强、对采样频率的要求不高。通过在PSCAD中搭建±800 kV直流输电模型并结合Matlab仿真结果表明,该方法可实现直流输电系统故障的准确辨识,且能实现故障选极,具有一定的实际工程价值。更多还原

【Abstract】 Identifying the faults of UHVDC transmission system reliably and accurately is the basis of protection action inside and outside the UHVDC transmission system,which is of decisive significance to safe and reliable operation of the whole HVDC transmission system.Based on the Berrellon distributed parameter model,a fault identification criterion is proposed by introducing the transient energy deviation(the ratio of transient value to normal value)on the basis of the directional current method,which can identify rectifier outlet fault,DC line fault and inverter outlet fault in UHVDC transmission accurately.This identification method has low requirement for DC line communication channel,strong ability of resisting transition resistance and low requirement for sampling frequency.By building the±800 kV DC transmission model in PSCAD and combining with the MATLAB,the simulation results show that the method can identify the faults of HVDC system accurately and select the fault poles,which has a certain practical engineering value.更多还原