CAJ | 학술논문

针对风电场中性点经高阻接地系统汇集线母线单相故障时常规母线差动保护灵敏度不足的问题，提出一种基于波形识别原理的高灵敏度差动保护方法。该方法识别故障波形特征，根据负荷情况实时调整浮动门槛值，同时，根据系统谐波含量实时调整差动比率系数，有效避免因谐波引起的高灵敏度差动保护误动作。RTDS 的仿真结果表明，该方法能够保证中性点经高阻接地系统在发生单相故障时，迅速切除故障。该方案的应用，对于保护电气设备、维护风电系统稳定运行具有重要意义。
침대풍전장중성점경고조접지계통회집선모선단상고장시상규모선차동보호령민도불족적문제，제출일충기우파형식별원리적고령민도차동보호방법。해방법식별고장파형특정，근거부하정황실시조정부동문함치，동시，근거계통해파함량실시조정차동비솔계수，유효피면인해파인기적고령민도차동보호오동작。RTDS 적방진결과표명，해방법능구보증중성점경고조접지계통재발생단상고장시，신속절제고장。해방안적응용，대우보호전기설비、유호풍전계통은정운행구유중요의의。
When the high resistance neutral point grounded system in wind farm occurs a single-phase fault, the conventional busbar differential protection has sensitivity problem. To avoid this situation, a high sensitivity differential protection based on the principle of waveform recognition is proposed, which identifies fault waveform characteristics, adjusts floating threshold according to real-time load and the differential ratio factor according to harmonic content of the system. The method can effectively avoid malfunction of high sensitivity differential protection caused by harmonic wave. RTDS simulation results show that this method can isolate fault quickly when a single-phase fault occurred in the high resistance neutral point grounded system. The application of the proposed method is of great significance to protecting electrical equipment and maintaining the stable operation of the wind system.