A Review of Test Voltages Used in Partial Discharge Measurements

Abstract

This paper presents a literature review on the variety of test voltages used in partial discharge (PD) measurements. The relationship between electrical equipment, PD measurement and test voltage has been addressed. Conventional (based on the IEC60270 standard) and unconventional method are the main methods of electrical PD detection and measurement. These methods can be done under on-line and/or off-line conditions with each method having its own advantages and disadvantages. Despite the condition or method of detection, the test voltages presented, among others, are impulse, direct-current (DC), harmonics, damped alternating current (DAC), power frequency voltage and very low frequency (VLF). For each diagnostic test, the most suitable test voltage of choice is selected based on the specifications and requirements of the device under test. However, a single measuring technique might not be sufficient to completely analyze and assess the health status of the insulation. Therefore, the use of multiple techniques may be recommended in order to create a more comprehensive picture and yield better results.