The Measurement Method for Corona Discharge Current Under High-Voltage Environment

Measuring corona discharge current directly on the high-voltage side is essential for the discharge mechanism research of the test object. The amplitude of the corona discharge current is in microamperes, and its frequency ranges from DC to megahertz. An optical microcurrent transducer for measurement of the current is described in this paper based on an amplitude modulation principle. A low-pass filter is used to extend the analog fiber link to recover low-frequency signals. The uncertainty of the transducer is estimated to be less than 1.3% in ratio, and its response frequency range is from DC to several megahertz.