核电站继电保护控制电路卡的检测和维修技术

Testing and Repair of Protective Control Circuit Card for Nuclear Power Plant

介绍了一种新型继电保护控制卡件(以下简称卡件)的检测技术--老化状态检测法:通过对电路图原理分析,确定各个电路节点的基准工作电压(设计电压)、维持正常工作的极限工作电压(上、下限),以及状态转换的时间,再根据具体的电路卡件来设计一个状态检测装置,对卡件进行非破坏性的检测和试验,即可知道被检测的卡件是否还能正常工作;如果检测时输入卡件的序列号,形成每个卡件专有的历史性能数据,就可根据各个节点的电压或者状态转换时间的趋势变化,评估卡件上某些元器件的老化状态,这样就可以在卡件失效前发现问题,避免卡件故障影响核电站的正常运行;对卡件进行恢复性维修,延长卡件的寿命。通过对LG_A325E过流保护卡件和LG_A326E过负荷保护卡件的检测和维修,取得了预期的检测结果,并意外地发现了卡件设计上的缺陷,提出相应的解决措施。

This paper describes a new type of detection technology for relay control card（hereinafter referred to as the card）- aging state detection method. By analyzing the principle of the circuit diagram, we can determine the referencevoltage（ design voltage） and limit voltage（upper and lower limits） for maintaining normal work and the time required for state transitionof each circuit node. Then in accordance with specific circuit cards, a state detecting device could be designed to conduct non-destructive detection and test on the cards. Consequently, we can know whether the card which was detected can work properly or not.If we enter the serial number of the cards during the process of detection, it can form a proprietary historical performance data base of each card, thus we can evaluate the aging state of some components on the cards by analyzing each node voltage or trends of state transition time. In this way, we can find the problems before card failureand perform a recovery maintenance on the cards timely to prolong the life of the cards.By detecting A325 E over current protection card in a power station, we obtainedthe expected detection result and discovered the design flaws of cards accidentally.