Spatial electromagnetic suppression in ultra-high voltage(UHV) partial discharge test

Varieties of interference sources involve in UHV partial discharge site test. Their routes have to be carefully studied, so that suppression and shielding techniques can be implemented accordingly. In our UHV site test, corona of neighboring 500kV operating equipment couples in significant special electromagnetic noise signal via large coupling capacitance. As the test limitation is strict, the special noise impedes judgment of test results. In this article, nose signals in partial discharge test have been classified. Characters of spatial electromagnetic noise have been studied, and resultant noise signal capturing and processing techniques have been developed. Success of the partial discharge site test has been guaranteed.