A Novel Archimedes Spiral Antenna Used for PD Measurement at Repetitive Square Wave Voltages

Abstract

Partial discharge(PD) measurements under repetitive impulsive voltages should be performed on insulation systems of rotating machines fed by voltage converters for type and qualification tests according to International Electrotechnical Commission (IEC) standard. Compared with well-established PD test technologies at sinusoidal voltages, more issues should be considered when PD detection are carried out using repetitive impulsive voltages, because PD pulses coming from the samples and the disturbance coming from impulsive voltage generator often have similar features in both time and frequency domains. Among all PD measurement methods, ultra-high frequency (UHF) technologies are recommended to be used under repetitive impulsive voltage conditions because the UHF sensors with appropriate bandwidth can receive PD energy in high frequency range with high signal to noise ratio (SNR). However, when performing PD tests using UHF method at impulsive voltages, the test sensitivity depends largely on the performance of the antenna in frequency domain. This paper, therefore, aims to present a design of a novel Archimedes Spiral Antenna (ASA) specially used for PD tests at impulsive voltages. Through the electromagnetic simulation, the optimized parameters of the antenna are selected and discussed. The PD tests at repetitive impulsive voltages show that the designed ASA can receive PD signals with high SNR and can be used for partial discharge inception voltage (PDIV) tests on insulation systems/models according to the IEC 60034-18-41 and IEC 60034-27-5.