汽轮机液压油系统引起机组异常跳闸的分析

对沙角B电厂发生的一起机组跳机事件进行了详细的试验研究和调查分析,找到了故障原因:油系统中杂质造成推力瓦磨损检测装置内油压瞬间波动引起汽轮机蒸汽阀门的关闭而最终引发跳闸。针对汽轮机油系统内部存在的安全隐患,提出相应对策和解决措施:平时在进行推力瓦磨损试验过程中,为了避免因液压装置的延迟复位而造成试验值偏差或跳机,必须确认系统状态并且动作过程尽量缓慢;下次大修中需对汽机油系统设备进行解体清洗。

Analysis on an unusual trip caused by the hydraulic oil system of steam turbine

Based on the overall test and analysis, the cause of trip fault in Shajiao B Power Plant was found out. The thrust bearing abrasion by the contaminants in oil system leads to a transient fluctuation of oil pressure inside the test device, which results in the closing of turbine valve, even the tripping. In view of the safety implication inside the turbine oil system, the countermeasures and solution were proposed. During the routine abrasion test on thrust bearing, the system state must be confirmed and the operation should be slow as possible to avoid the test error or tripping resulted from reset delay of the hydraulic unit. The devices of turbine oil system are required disassembling for a thorough cleanout in the next overhaul.