Simulation of Partial Discharge in Solid Dielectric Material

In high voltage (HV) electrical power system, variety of solid, liquid and gaseous materials are used for insulation purpose to protect the incipient failure inside the HV power equipment. Partial discharge (PD) represents a physical phenomenon, in which discharges are involved in electrically weak regions of solid insulation materials (mostly within gaseous or liquid inclusions). They cause damage to the insulation and often start from the enclosed voids and/or at interface defects. The period in which the insulation is still in good operating condition is of great practical interest. The effect of PD also results in failure of the dielectric much before the expected life-time. This project focused on the results of the partial discharges in solid dielectric with a single cavity as defect. AC source with 50Hz frequency voltage was applied. It is observed that the discharge current is proportional with the input voltage. The discharge current amplitude for input 10 kV is half the input of 20 kV and a third of 30 kV input. All discharge currents and discharge voltages occur in nano-seconds.