特高压交流开关型可控避雷器控制系统设计

Control System Design of UHV AC Switch Type Controllable Arrester

随着电压等级的升高,操作过电压对输变电设备的绝缘水平影响逐渐变大。开关型可控避雷器是特高压交流输电系统中一种有效的操作过电压限制手段,而控制系统是可控避雷器的关键组成部分,通过实时监测线路电压电流状态智能控制避雷器的参数和性能以达到深度抑制操作过电压的目的。根据可控避雷器的功能需求,阐述了可控避雷器控制系统的基本原理和整体构成,各个组成部分的功能设置和可控避雷器的自动控制策略;同时介绍了控制系统的可靠性设计措施,根据统计故障率计算了控制系统的平均失效间隔工作时间(mean operating time between failures,MTBF)值;最终按照设计要求研制出了控制系统样机,并对控制系统进行了电气性能实验,充分验证了研制的控制系统的有效性和可用性。实验结果表明,可控避雷器控制系统控制结构清晰,策略有效,具备在特高压交流输电系统中工程应用的条件。

Along with the increase of voltage level,the influence of the switching overvoltage on the insulation level of the power transmission equipment becomes larger.The switch type controllable arrester is an effective switching overvoltage limiting method in the UHV AC transmission system.The control system is a key component of the controllable arrester whose parameters and performance are intelligently controlled according to the line voltage and current state so as to deeply suppress the switching overvoltage.Adhering to the functional requirements of the controllable arrester,the basic principle and overall structure of the control system are first put forward in this paper,including the function settings of each component and the automatic control strategy.Then the reliability design measures of the control system are introduced and the mean operating time between failures(MTBF)value is calculated with the statistical failure rates of each components.Finally,the control system prototype is developed as needed by the design requirements and the electrical combined test of the control system is carried out,which fully verifies the reliability and availability of the developed control system.The test results show that the control system has a clear control structure and effective strategies,and it meets the conditions for engineering application in UHV AC transmission systems.