一起550kV断路器合闸电阻阻值超标现象分析

Analysis of an Excessive Resistance Phenomenon of 550 kV Circuit Breaker Closing Resistor

在例行试验时发现550 k V断路器合闸电阻阻值超标,通过解体、试验,发现由于该型号合闸电阻具有负温度特性,其阻值会随环境温度的降低而变大。为确保在现场准确测量合闸电阻阻值,提出了该型号产品在生产时应充分考虑环境温度的影响,在测量时记录环境温度并进行阻值换算的改进措施。

The resistance of a 550 k V circuit breaker closing resistor was found exceeding the standard value in a routine test. Then disassembly inspection and test were conducted. It was discovered that this type of closing resistor possesses a negative temperature characteristic, and its resistance increases when the ambient temperature decreases. In order to ensure accurate on-site measurement of the closing resistor, it is suggested that the influence of ambient temperature should be considered in production of this type of closing resistors, and ambient temperature ought to be recorded for resistance conversion in process of measurement.