光伏T接高压配电网电流差动保护研究

摘要

分析了光伏电站故障电流的特性，研究了两个目前常用电流差动保护判据应用在光伏T接线路上存在的问题。研究结果表明，传统T接线路差动保护判据不能同时满足内部故障的灵敏性和外部故障的可靠性。结合光伏电源故障电流特点，提出了适合于光伏T接线路电流差动保护的综合判据。对改进后的判据进行了大量的仿真试验，仿真结果表明，该判据能满足区内故障时的灵敏性和区外故障时的可靠性，并且具有很强的抗过渡电阻的能力。%The characteristic of fault current of photovoltaic power is analyzed. Research on the problems that two traditional criterions of current differential protection used in photovoltaic T-type line has done and results show that traditional criterions cannot simultaneously meet the sensitivity and reliability. Combining with the characteristic of fault current of photovoltaic power, a synthesis criterion of current differential protection suitable for photovoltaic T-type line is proposed. A lot of simulation has done and simulation results show that the synthesis criterion can not only satisfy the sensitivity and reliability but also has a strong resistance to the fault resistance.