Research on the Relationship between Surface Temperature Rising and Internal Faults of MOA

Metal oxide surge arrester (MOA) is an over-voltage protection equipment of power system. The internal faults are often showed by the temperature rising on the outer surface, so that the online operation state of MOA can be analyzed by detecting the surface temperature rising to diagnose fault. In this paper, the characteristics of temperature rising of MOA were analyzed by detecting the infrared image, and a multi physical field coupling model of a single section MOA based on finite element method (FEM) was established to discuss the inside and surface temperature rising changes under the normal operating condition and heating fault one. Furthermore, the maximum temperature rising of MOA under different ambient temperature and different fault heating source power is compared. Through the research on infrared temperature rising detection, the numerical simulation results are consistent with the detection one, the result accuracy of simulation is testified. Under the same heating source, the surface temperature rising of MOA in low temperature environment changes markedly, and the maximum value of surface temperature rising decreases with the increase of ambient temperature. The detection of infrared temperature can be used as an effective means for MOA online monitoring and fault diagnosis. While the data processing results can assist in setting the detection standards and be applied to the decision-making of MOA operation and maintenance.