论文部分内容阅读
某电厂1号高压引风机突然跳闸,运行值班员强行合闸成功,但运行不到1min再次跳闸。按规程不能再强行合闸,则起动备用风机将1号引风机停机检修。 经检查两次跳闸发出的均是零序信号,随即对电缆、电机做绝缘检查,测量无异常后又做直流泄漏试验也没有发现问题,经现场分析终于真象大白。此故障带有偶然性。 当天车间为1号引风机高压电机加装防侧雨罩,在原防雨罩上电焊,电焊工将焊机地线搭接在公共接地线上只拖焊把线对防雨罩焊接,在焊接时也听到风机变音直至最后停转。也没有注意。运行人员来检查时即反映了此情况。经分析认为零序保护误动。
A power plant on the 1st high-pressure induced draft fan suddenly trip, the force on-duty forcibly closed successfully, but run less than 1min trip again. According to the rules can no longer be forced to close, the standby fan will be No. 1 Fan Fan overhaul maintenance. After checking the two trips are issued zero sequence signal, then cable, motor insulation inspection, no abnormalities after the test and then do DC leakage test did not find the problem, the field analysis finally tell the truth. This fault is accidental. The same day workshop No. 1 induced draft fan high-voltage motor with anti-side rain cover, the original rain cover welding, welders will ground welding machine lap in the public ground only on the welding line soldering rain cover welding, welding Fan also hear the sound until the last stop. Also did not pay attention. This is reflected when the operator is checking. After analysis that zero-sequence protection misoperation.