经柔性高压直流输电并网的海上风电送出线路拟功率和、差波形比较式纵联保护  

Quasi-power sum and differential waveform comparison type pilot protection for VSC-HVDC grid-connected offshore wind power outgoing line

作　　者：刘乃皓 高厚磊[1] 徐彬 彭放[1] 袁通 LIU Naihao;GAO Houlei;XU Bin;PENG Fang;YUAN Tong(College of Electrical Engineering,Shandong University,Jinan 250061,China)

机构地区：[1]山东大学电气工程学院,山东济南250061

出　　处：《电力自动化设备》2024年第8期62-69,共8页Electric Power Automation Equipment

基　　金：国家自然科学基金资助项目(52277109)。

摘　　要：经柔性高压直流输电并网的海上风电送出线路在故障情况下呈现出的两端电流存在较大相角差等故障特性导致传统纵联保护面临不能正确动作的风险。根据电路中的拟功率定理,分别利用线路两端故障前后电压、电流瞬时值列写拟功率表达式,并对两表达式进行求和与作差运算,得到拟功率和与拟功率差。分析表明,发生区内故障时,两者波形相似性高,波形接近完全重合;发生区外故障时,两者含有成分不同,相似性较差,据此形成拟功率和、差波形比较式纵联保护的保护判据。利用EMTP-RV软件搭建经柔性高压直流输电并网的海上风电场模型,对不同故障类型、过渡电阻、噪声、数据窗长、控制方式、同步误差进行仿真验证,理论分析与仿真结果表明所提保护方法具有较强的适应性。The voltage source converter based high voltage direct current transmission(VSC-HVDC)grid-connected offshore wind power outgoing line shows fault characteristics such as large phase angle differences between current at two ends during faults,which poses a risk of traditional pilot protection,not being able to operate correctly.According to the quasi-power theorem in the circuit,the quasi-power expressions are written by using the instantaneous values of voltage and current before and after faults at both ends of the line.And sum and difference operations are performed on the two expressions to obtain the quasi-power sum and quasi-power difference.The analysis show that when an internal fault occurs,the waveforms of the quasi-power sum and quasi-power difference are highly similar,and nearly completely coincident,while when an external fault occurs,the similarity between the two waveforms is poor.Based on this,the protection criteria of the pilot protection of the quasi-power sum and the quasi-power differential waveform are formed.The model of a VSC-HVDC grid-connected offshore wind farm is built by the EMTP-RV software.The proposed method is simulated and verified under different fault types,transition resistances,noises,data window lengths,control modes and synchronization errors.The theoretical analysis and simulative results show that the proposed protection method has strong adaptability.

关 键 词：海上风电场 拟功率和 拟功率差 肯德尔相关系数 相似性 送出线路 继电保护 

分 类 号：TM77[电气工程—电力系统及自动化]