Harmonic wave analysis of conductor corona current based on wide frequency band measurement

Corona current is one of important corona characteristic research contents. In order to analyze conductor corona current harmonic wave characteristic, a corona current measurement system is developed. The synchronous collect of the voltage and current signal is realized by the GPS technology. The corona current signal is transmitted to the lower computer through the wireless network. And the current signal collected in this way is safe and reliable. The measurement system can be used to measure the wide frequency band corona current. Advanced Hanning windowed interpolation FFT algorithm was adopted, and conductor corona current harmonic wave was analyzed. Corona current harmonic characteristics before and after corona onset were compared. Research results show that, after corona onset, corona current odd harmonic increases in evidence, and even-order harmonic increase less relatively. Triple-frequency harmonics and quintuple harmonics increase obviously very much, and conductor corona current harmonic analysis can be used to research conductor corona characteristic.