The Study Of Transformer's DC Resistance Rapid Measurement Method

Transformer's DC resistance measurement is one of the primary item before transformer leaving factory and precautionary,and the DC resistance must be measured in the course of manufacture, heavy repair, connective test, testing average temperature rise and fault diagnoses, so it is quite vital to measure DC resistance of windings nicely. Because power transformers usually have big inductance but small resistance, they have big inherent time. The time of measuring DC resistance is very long, so it is very important to study to shorten measuring time. In this dissertation, all kinds of rapid measuring methods are studied, their advantage and disadvantage is analyzed and their on-site applicability is compared. A new rapid measuring method is founded combining the saturable magnetic circuit method and constant-current source, in order to fast measure transformer's DC resistance. In this paper, introducing kinds of constant current sources and their keystone, and designing the adjusting constant current source, the results of the examination is good. In the end, I have accomplished the measurement equipment's hardware design and software design.