江苏春晨电缆有限公司生产春晨扁电缆YCB324356，

电力系统内部、外部过电压

Internal and external overvoltage of power system

电力系统由于外部（如雷电放电）和内部（如故障跳闸或正常操作）的原因，会出现对绝缘有危害的持续时间较短的电压升高，这种电压升高（或电位差升高）称为过电压。由雷电活动引起的过电压称为外部过电压（简称外过电压），包括直击雷过电压和感应雷过电压；而由电力系统内部操作和故障引起的过电压称为内部过电压（简称内过电压），包括操作过电压和暂时过电压，其中暂时过电压又分为工频过电压和谐振过电压。春晨扁电缆YCB324356过电压不仅对电力系统的正常运行造成威胁，而且对带电作业的安全也很重要。因此，在设备绝缘配合、带电作业安全距离选择、绝缘工具短有效长度以及绝缘工具电气试验标准中都必须考虑这一重要因素。

Because of the external (such as lightning discharge) and internal (such as fault tri*ormal operation) reas*, the power system will h*e a short duration voltage rise which is harmful to the insulation. This voltage rise (or potential difference rise) is called overvoltage. Overvoltage caused by lightning activities is called external overvoltage (referred to as external overvoltage), including direct lightning overvoltage and induced lightning overvoltage; while overvoltage caused by internal operation and fault of power system is called internal overvoltage (referred to as Internal Overvoltage), including operating overvoltage and temporary overvoltage, in which temporary overvoltage is divided i* power frequency overvoltage and resonance overvoltage. Overvoltage is not only a threat to the normal operation of power system, but also very important to the safety of live working. Therefore, this important factor must be c*idered in the insulation coordination of equipment, the selection of safe distance for live working, the shortest effective length of insulating tools and the electrical test standard of insulating tools.