提高中压电子式电压互感器温度稳定性的新方法

New Method That Improving Temperature Stability of Electronic Voltage Transformer in Middle Voltage

介绍了采用电阻分压原理的电子式电压互感器的原理及结构,分析了影响其温度特性的因素。针对多个中压电子式电压互感器进行了温度试验,在-25°C及40°C的条件下分别测量分压比,计算温度变化导致的误差。根据试验结果,建立了一个分压比和温度变化的关系模型。根据模型,针对部分温度特性不稳定的互感器,提出了一种采用热敏电阻的温度补偿办法提高中压电子式电压互感器温度稳定性,并完善了算法。对经过温度补偿后的中压电子式电压互感器再次进行了温度试验,结果在-25～40°C条件下电压互感器的测量比差最大为±0.2%,试验结果与理论分析能够很好地相符。因此,适当的选择温度补偿可以抵消温度变化对电阻分压原理的电子式电压互感器导致的误差。

We introduced an electronic voltage transformer which was based on the principle of the voltage divider, and presented the principle and structure of electronic voltage transformer. The impact of the temperature characteristics was also analyzed. Temperature tests of some electronic voltage transformers were carried out at temperatures from -25 ℃ to 40 ℃. The calculation errors caused by temperature change were analyzed. Results show that selecting the appropriate size of temperature compensation can reduce the errors of electronic voltage transformer caused by the temperature change.