一起长引水隧洞机组过负荷事故的分析与处理

Analysis and treatment of overload accident of a long diversion tunnel unit

针对上通坝电站一起机组过负荷事故,通过查找事故发生前后数据,对机组过负荷事故进行了分析。发现机组过负荷是由于机组频繁调整负荷,使得机组负荷一直未能调整到位,有功调节超时造成机组有功调节退出,再加之受长引水隧洞水流惯性影响,机组蜗壳进口水压迅速上涨,使得机组负荷快速上升,而机组LCU程序逻辑存在缺陷,当机组有功功率值超过程序设定值时,机组有功调节会自动退出,并且无法被再次投入,造成了机组在较长的一段时间内严重过负荷。通过对机组LCU程序进行修改完善,消除了机组过负荷时无法进行有功调节的隐患。

For a unit overload accident at Shangtong Dam Power Station,the unit overload accident was analyzed by finding the data before and after the accident.It is found that the overload of the unit is due to the frequent adjustment of the unit load,so that the unit load has not been adjusted in place,the active adjustment timeout causes the active adjustment of the unit to exit,coupled with the inertia of the water flow of the long diversion tunnel,the water pressure of the volute inlet of the unit rises rapidly,so that the unit load rises rapidly,and the LCU program logic of the unit is defective,when the active power value of the unit exceeds the program set value,the active adjustment of the unit will automatically exit and cannot be re-entered,causing the unit to be seriously overloaded for a long period of time.By modifying and improving the LCU program of the unit,the hidden danger of not being able to carry out active adjustment when the unit is overloaded is eliminated.