Compensation Method for Improving Capabilities of AC Current Test Equipment

Testing of electrical equipment with AC currents is a common test in both high power and high voltage laboratories. It implies driving currents, sometimes several tens of kilo-amperes high, through a test object loop conductor. Test transformers are normally used as current sources, but the limiting factor is usually their relatively low rated voltage. Voltage on the test transformer is determined by product of loop impedance and test current. Proposed compensation method deals with reduction of loop impedance which consequently reduces voltage on test transformer and improves test capabilities. Experimental verification of the method was successfully carried out on two test objects: 110 kV cable and 600 kV transformer bushing. (Free access link: http://authors.elsevier.com/a/1QHlJ1M7~0LqM3)