Dry-type air-core reactor plays an important role in regulating reactive power of grid.However

during the operation period of the reactor

the short circuit fault can caused by such reasons as aging of insulation material

partial over heat etc

resulting in serious accident and causing huge economic losses.At present

the insulation performance detection method of the air-core reactor is to judge whether the reactor has fault by way of comparing both decay and frequency variation of the voltage oscillation wave on both sides of the reactor which is caused by the inductance variation of the reactor.In this paper

the parameters of oscillation circuit is determined by setting up the simulation model of the oscillation wave system so to detect the partial discharge during the oscillation period

in which the partial discharge detection contains such method as ultra-high frequency method

high frequency method

pulse current method and ultrasonic method as well as comprehensive detection.It is shown by the test that the potential fault of the air core reactor can be found and the occurrence of malignant accident can be avoided.