煤矿自适应微机电流速断保护的研究

针对煤矿6 kV下井线比较短,灵敏度和保护范围直接受电网系统运行方式和短路类型影响,常规微机电流速断定值整定方案往往导致线路没有保护范围,发生短路故障常引起越级跳闸这种情况。利用自适应技术,通过对每条线路的电压、电流进行实时监视和分析、自动识别系统运行方式来改变微机保护的整定值和特性。分析表明自适应速断保护用作相间保护不用判断故障类别,且能够使保护装置始终获得最佳保护性能,可对提高矿井的安全供电提供技术支持。

Research on microcomputer-based current instantaneous trip protection

The common setting calculation of microcomputer-based current instantaneous trip protection results in the circuitry without extent of protection sometimes,then bring about jump the over trip when occur short circuit faults of circuitry.For the line of 6 kV is short in underground mine,besides the sensitivity and extent of protection are affected by operation mode and fault type of power system directly.According to the existing problems,a new method that the operation mode of electric power system is able to be identified automatically with adaptive technique was used,which can change the set point auto-turning and the characteristic of protection,through the surveillance and analysis to voltage and current of each line with real time,and it is not necessary to judge fault type as phase faults protection,which makes the function of microcomputer current instantaneous trip protection relays is always best,it could provide technical source for improving safety power supply in mine.