微型电脑应用

针对抽水蓄能机组现有继电保护功能不完善、可靠性较低等问题，提出一种抽水蓄能电站发变电机组智能差动保护控制策略。分析纵联和横联差动保护原理，对于现有频率跟踪算法存在的计算速度慢、准确性偏低等不足，提出基于短数据窗口的频率跟踪算法。结合故障分量电流与全电流差动、零序及负序电流的保护机制，设计一种自适应智能差动保护控制策略。通过算例仿真结果表明，所提策略可以准确、可靠地断开机组内部故障，同时有效避免机组外部故障的误动作。在实际抽水蓄能电站的应用中，所提策略也能够提高继电保护装置动作的可靠性，将故障未可靠动作比例由1.48%降低至0.64%。

Aimed at the problems of imperfect function and low reliability of pumped storage units relay protection, an intelligent differential protection control strategy for generation and substation unit of pumped storage power station is proposed in this paper. The principle of longitudinal differential protection and transverse differential protection is analyzed, a frequency tracking algorithm based on short data window is designed to solve the problem of the existing frequency tracking algorithm, such as slow calculation speed and low accuracy. An adaptive intelligent differential protection control strategy is designed, combined with fault component current differential protection, full current differential protection, zero sequence current and negative sequence current protection. The simulation results show that the proposed intelligent differential protection control strategy can accurately and reliably disconnect the internal faults of the unit, and effectively avoid the mis-operation of external faults of the unit. In the practical application of pumped storage power station, the control strategy designed in this paper can improve the action reliability of relay protection device with a reduction in the proportion of the unreliability action from 1.48% to 0.64%.