Investigation of Factors Affecting Partial Discharges on Epoxy Resin: Simulation, Experiments and Reference on Electrical Machines

Abstract

[EN] In Power Systems, SG are mostly used for generating electricity. Their insulation system, of which epoxy resin is a core component, plays a significant role reliable operation. Epoxy resin has high mechanical strength, a characteristic that makes it a very good material for reliable SG¿ insulation. PD are a constant threat to this insulation since they cause deterioration and conse-quential degradation of the aforementioned material. Therefore, it is very important to detect these PD, as they are both a symptom of insulation deterioration and a means to identifying possible faults. Offline and Online PD Tests are described and a MATLAB/Simulink model, which simulated the capacitive model of PD is presented in this paper. Moreover, experiments are carried out in order to examine how the flashover voltage of epoxy resin samples is affected by different humidity levels. The main purpose of this manuscript is to investigate factors such as applied voltage, number and volume of water droplets, water conductivity, which affect the condition of epoxy resin and how they are related to PD and flashover voltages which may ap-pear also in EM insulation. The aforementioned factors may affect the epoxy resin resulting to an increased number of PD, which increases overall EM risk factor.