用直流双电桥测量特小电阻的方法研究

小电阻测量一般用直流双电桥.虽然直流双电桥针对接头处的接触电阻和连接导线的电阻采取了双对接头的消除误差的措施,但靠被测电阻内侧的电位端依然存在很小的接触电阻,这部分电阻将影响到特小电阻的测量精度.如果采用两步差值测量法特小电阻可以轻松排除所有测量的导体电阻和接触电阻,直流双电桥都用此法,可全面提高测量精度,以及辅助判断测量精度.

The Study of the Measure Method to Unusual Little Resistances with Direct Current Kelvin Double Bridge

Commonly the measure of little resistance is direct current Kelvin double bridge Although direct current Kelvin double bridge adopts the step of two double tiein to reduce errors in the light of the contact resistance at the junction and the resistance of the linking wires, the little contact resistance still exists at the electric potential end, which is by the inside of the measured resistance This resistance will affect the measuring the accuracy of the unusual little resistance But the method of two-steps could eliminate the effect of all the measured conductor resistance and contact resistance easily In this way, direct current Kelvin double bridge can not only enhance the measuring accuracy all-sidely but also help judge it