Abstract:With the rapid development of clean energy, new energy combined with flexible low frequency AC power transmission has become a new development direction. In order to meet the engineering application requirements of low frequency AC power system, adaptability research must be carried out for conventional AC relay protection. Starting from the busbar protection, this paper discusses the existing busbar protection principle, and analyzes the influence of different sampling intervals on the result of sample value product algorithm. For 20Hz low frequency power system, a new criterion for low frequency bus differential protection is proposed based on the sample value product algorithm. The fault characteristic quantity is quickly calculated based on sample value product algorithm, and the reliability of fault judgment is guaranteed by combining with instantaneous value criterion. The simulation results show that the low frequency busbar protection based on the new criterion can meet the requirements of the existing technical specifications for the reliability and speed of busbar protection. The whole fault clear time is less than 20ms for faults within the busbar area, and the low frequency busbar protection does not operate for faults outside the busbar area.
丁杰, 吕航, 王风光, 龚啸, 赵国勇. 应用于低频电力系统的母线差动保护判据研究[J]. 电气技术, 2023, 24(10): 44-50.
DING Jie, LÜ Hang, WANG Fengguang, GONG Xiao, ZHAO Guoyong. Research on bus differential protection criterion applied to low frequency power system. Electrical Engineering, 2023, 24(10): 44-50.