并列运行的发电机无功功率波动的原因分析及处理

Cause Analysis and Iteatment of Reactive Power Fluctuation of the Parallel Running Generator

某核电厂3号机组配置两台并列运行的控制棒驱动机构电源系统发电机,为反应堆控制棒驱动机构整流装置提供260 V交流电。机组运行期间,两台发电机同时出现无功功率波动的情况,并呈现出波动幅度较大和波动周期较短的特点,且波动幅度无明显的规律。对两台发电机停机检修,发现其中一台发电机的调差电路存在端子氧化的情况,造成该发电机调差参数发生无规律的变化,进而导致两台发电机无功功率波动。更换氧化的端子元器件后,两台发电机重新并网运行,发电机无功功率分配均匀且稳定。

Unit 3 of the nuclear power plant is equipped with two RAM generators running in parallel to provide AC 260 V power to the rectifier device of the reactor control rod drive mechanism.During the operation of the unit,reactive power fluctuations occur in both generators at the same time and are characterized by large fluctuations and short fluctuation periods,with no obvious pattern in the fluctuations.When two generators are shut down for maintenance,it is found that the terminals of the differential circuit of one of the generators are oxidized,which cause irregular changes in the differential parameters of the generator,resulting in fluctuations in the reactive power of both generators.After replacing the oxidized terminals,the two generators are put back on the grid and the reactive power distribution becomes uniform and stable.