Analyzing the Impact of Short-Term Cyclic Thermal Ageing on PVC Insulated Low Voltage Samples with Polarization/Depolarization Current Measurement

Abstract

Cables are critical elements of the network. Therefore, their integrity is of utmost importance. Many factors influence the insulation integrity of the cables, such as manufacturing procedures, operating conditions, and various stresses, during their lifetime. Increasing the number of renewables resulted in increased distributed generation, which may cause reverse power flow. The electricity demand is constantly growing with the increased number of novel appliances on the consumer side, electric vehicles, etc. This fact can create short-term overloads, which may cause a temperature elevation beyond the cable's maximum operating limit, compromising insulation degradation. Therefore, this research investigates the impact of short-term cyclic thermal ageing on SZRMtKVM-J 4 x 6 mm PVC insulated low voltage cable using the polarization/depolarization current measurement (PDC). Accelerated thermal ageing tests were performed by placing the samples inside the temperature-controlled oven for 6 hours/round. After each round, the polarization and depolarization currents were measured. DIRANA Dielectric Response Analyzer by Omicron has been employed for the measurements. The results have shown an increase in the polarization and depolarization current.