水电能源科学

抽水蓄能电站具有频繁开、停机和工况切换的特点，对电站的安全运行影响较大。但目前关于抽水蓄能电站地下厂房结构在机组振荷载作用下的振动响应现场监测资料很少，尤其缺乏机组开、停机及甩负荷等瞬态工况下的振动监测。以某抽水蓄能电站地下厂房为例，开展了发电、抽水开停机和不同出力甩负荷等瞬态工况下的动力特性监测分析。监测分析结果表明，瞬态工况下厂房结构各典型部位的振动响应峰值明显大于稳态工况，其中机组发电开停机工况振动响应大于水泵抽水工况，但振动位移和加速度基本均能满足目前振动标准建议限值；100%甩负荷工况下厂房结构的振动响应最为强烈，最大振动加速度可达30 m/s²以上，容易造成厂房结构冲击性损伤，建议电站日常运行时尽量避免100%甩负荷工况的出现，万一发生后要及时对厂房关键结构部位进行巡检，排除安全隐患。

The pumped storage power station has the characteristics of frequent unit start-up and shutdown and working condition switching, which has great influence on the safe operation of the power station. At present, the on-site monitoring data of the vibration response of the underground powerhouse structure of pumped storage power station under the vibration load of the unit are few, especially the vibration monitoring of the unit under the transient conditions such as unit start-up and shutdown and load rejection. This paper takes the underground powerhouse of a pumped storage power station as the research object, and carries out the dynamic characteristics monitoring analysis under the transient conditions of power generation, pumping switch and different output load rejection. The results show that the peak vibration response of each typical part of the powerhouse structure under transient condition is obviously greater than that under steady condition, and the vibration response under power generation on and off condition is greater than that under pump pumping condition, but the vibration displacement and acceleration can basically meet the recommended limits of the current vibration standard. Under 100% load rejection conditions, the vibration response of the powerhouse structure is the strongest, and the maximum vibration acceleration can reach more than 30 m/s², which is easy to cause impact damage to the powerhouse structure. It is recommended to avoid 100% load rejection conditions during daily operation and maintenance of the power station. In case of occurrence, it is necessary to timely detect the key structural parts of the powerhouse to eliminate safety risks.