Polarisation spectrum analysis for diagnosis of oil/paper insulation systems

This new method can be described as the diagnosis of the state of an oil/paper insulated high voltage system by polarisation spectrum obtained from the results of recovery voltage measurement. The technique of recovery voltage measurement offers a useful non-intrusive diagnostic procedure for assessing oil-paper condition of transformers. The technique is primarily a comparative tool intended for repeat measurements over a period to indicate trends in insulation degradation. With experience, and taking due account of related factors such as temperature, recovery voltage measurement can also be used to give a quick indication of the health of the insulation system in any oil/paper insulated electrical equipment