The High-frequency Current Transducer for Measurement of PD under Impulse Voltage

In order to study partial discharge pulses under impulse voltage effectively, a high-frequency current transducer for measurement of PD is developed. According to the equivalent circuit model, its principle and transmission characteristics are analyzed, and the effects of coil turns, integral resistance and stray capacitance on frequency properties are studied. Moreover, calibration and analysis of the actual dynamic response are performed by adopting function generator and square-wave source. Performance tests show that it has good linearity and small phase shift with a wide bandwidth of 800 kHz-105MHz and high sensitivity of 2.4V A(-1). Based on the transducer, measurements of PD of needle-plate model under impulse voltage is identical to the results of theory analysis. It could be effective approach not only for deep study on PD character, but also to explore the mechanism under impulse voltage.