配电网故障指示器中电压测量的研究

配网故障指示器中电压的准确测量是故障识别的重要依据之一。仿真分析了配网不同接地方式下各种接地故障的电压特征,故障相或非故障相的电压变化特征可作为故障指示器故障识别的判据之一。设计了一种基于故障指示器机械结构,利用耦合电容分压的电压传感器,分析了配网线路对地架设高度不同及温度变化对电压传感器测量结果的影响。样机测试结果表明传感器在测量范围内的线性误差在±3. 8%之内,其作为电压变化特征的识别准确度足够。

Research on Voltage Measurement in the Field of Fault Indicator

Accurate measurement of voltage in the distribution network fault indicator is one of the important basis for fault identification. By analyzing the voltage characteristics of various ground faults under different grounding modes of the distribution network, it is pointed out that the voltage variation characteristics of the fault phase or non-fault phase can be used as one of the criteria for fault identification of fault indicators when the system has a ground fault. A voltage sensor based on the mechanical structure of the fault indicator is designed. Through theoretical analysis and simulation research, the influence of the temperature and different heights of the distribution line on the measurement results of the voltage sensor are analyzed. The prototype test results show that the linear error of the sensor in the measurement range is within ±3.8%, and its accuracy as a characteristic of voltage variation is acceptable.