The Influence Of Earthing Mode And Power Supply Mode On Microprocessor-based Protection Device

Microcomputer protection plays a very important role in the safe operation of power system,at the same time,it is used in the extremely bad electromagnetic environment of the substation,the Microcomputer protection is more sensitive to the electromagnetic interference. The paper discussed the reliability of Microcomputer protection through specific cases.First of all,it discussed the formation,characteristics and way of spreading to the secondary circuit of the interference source.Then the paper analyzed the level of anti-interference of the every port which are protected through the test to the sensitive equipments,and then discussed the influence of the anti-interference level of the device based on the situation of the direct earthing system and indirect earthing mode system.With the test results,the paper gave the realizable program to the direct earthing mode system.Finally,with the shortcoming of the anti-inference due to the centralized power supply,the paper gave the realizable program to the distributed power supply.