采用热敏检测的绝缘介质寿命记录仪  

Life Recorder of Dielectric Based on Microcontroller

作　　者：雷克刚[1] 吴广宁[1] 高波[1] 何景彦[1] 刘君[1] 

机构地区：[1]西南交通大学电气工程学院,成都610031

出　　处：《高电压技术》2007年第12期44-48,90,共6页High Voltage Engineering

基　　金：国家自然科学基金(50377035);霍英东教育基金(91060);教育部博士点基金(20050613008)。~~

摘　　要：在多路绝缘介质高压方波寿命试验中,为提高加速老化绝缘寿命试验的效率,设计了监控记录各试验支路状态的热敏检测绝缘介质寿命记录仪。该仪器通过PTC热敏电阻监测高压回路中限流电阻温度变化提取介质击穿信号,以单片机AT89c55为运算控制中心,采用热信号时间差分数字算法处理及控制信号。该方式受电磁干扰小,与高压回路无直接电气连接安全性高。该记录仪已实际应用,可在1~3 s内切除击穿支路,击穿时间记录误差〈2%,装置动作时间内因其限流电阻作用能有效保护脉冲电源。A life time recorder is required in the ageing life testing of dielectric material because parallel testing of multi-samples is allowed within less time costing and more exact data.A recorder based on the thermal resistors is used to monitor and record the state of the dielectric sample which is put into HV square wave life testing.The temperature of the limiting resistors installed in series in the HV test circuit is almost the same as the condition before the samples are broken down.Once one of the samples was broken down, the temperature of the limiting resistor connected to that sample will rise rapidly responding to the large energy loss on it.When the thermal resistor is placed near to the limiting resistor,the variation in temperature of the limiting resistor will be detected safely without connecting HV circuit by this way and can be used as the broken down criterion of the dielectric samples.The temperature signals will be transferred into analog electric signals by the thermal resistors,the analog signals will be transferred into digital signals by A/D converter,and the digital signals will be calculated by time differential algorithm in microcomputer AT89C55.The exact life recording with time percentage error less than 2% and quick cutting within 1~3 seconds of the broken down channel can be both achieved by this device.The life time recorder presented in this paper has been put into practical operation.

关 键 词：寿命试验 击穿 热敏电阻 检测 纪录仪 绝缘介质 

分 类 号：TM934.3[电气工程—电力电子与电力传动]