几个典型倒闸操作中对内部过电压的限制措施

内部过电压又称操作过电压或谐振过电压,对电气设备的安全运行和操作人员的人身安全构成严重威胁。通过对几个典型倒闸操作中(中性点直接接地系统中停送主变,带专用旁路母线的变电站进行代路操作,中性点非直接接地系统中,投运电磁式电压互感器,中性点直接接地系统中母线转热备用)内部过电压产生的机理,以及防止过电压产生的防范措施的作用机理进行一般性分析,说明在进行倒闸操作的过程中,有可能产生内部过电压,而针对不同的系统,不同的设备,采取不同的防范措施,则完全可以防止过电压的产生,从而有效地保护电气设备和操作人员的人身安全。

Internal overvoltage is called switching overvohage or resonance overvoltage, and it threatens the safe operation of electrical equipment and the personal security of operating personnel. Through analyzing the mechanism of internal overvoltage coming into being and the mechanism of preventive measures in several typical switching operations （stopping main transformer in neutral point direedy earthed system, substituting the circuit of substation with special bypass bus; putting electromagnetic potential transformer into operation in the system with non- directly earhed neutral; changing busbar to hot standby in neutral point directly earthed system）, it is illustrated that overvoltage will come into being during the process of switching operation, so different preventive measures should be adopted aiming at difference power system and electrical equipment to prevent overvohage from coming into being completely and to ensure the security of electrical equipment and operating personnel effectively.