大电流温升试验中铜排长度对试验误差的影响

Error Produced by Different Bus Length in Temperature Rise of Large Current Experiment

大电流电器设备在温升试验中需要使用截面积比较大的铜排,而大截面铜排的导热能力强,使得铜排另端的电源或电连接端子形成的热源对试验设备温升有较大干扰,可能导致试验误差。建立一维有限差分模型分析了大电流温升试验中铜排长度对试品温升造成的误差,给出了为减小误差而必须采用的铜排最小长度。其结论对大电流配电板设计中的温升问题有一定参考作用。

Large sectional area bus should be used in the temperature rise experiment with large- current electrical equipments. The large sectional area bus has a strong ability in heating transfer, so the heat source produced by the power source or the electrical connector in the other head of the bus can interfere the heating up test result of the test equipment. A one - dimension finite difference model is built to analyse the error of the test equipment produced by the length of the copper bus in large current beating up test. The shortest length of the copper bus is given to put down the error. The conclusion is also useful in the heating up problem in the design of the large current switchboard.