The Research On Electromagnetic Compatibility Of Merge Unit In The Power Case

With the continuous development of the national UHV DC transmission and transformation technology,digital substations have become the development trend of the power industry.The power cabinet merge unit is an important digital output port for electronic transformers.Its timeliness and accuracy of data transmission and processing are directly.Influencing the stability of the substation system.The power cabinet merge unit is one of the key devices in the process layer of the substation.As the electromagnetic environment of substations is getting worse,the ability of secondary equipment in substations to cope with complex electromagnetic environments has become the core competitiveness of many power equipment manufacturers.It has occurred many times in daily engineering applications due to MU data transmission in substations.The missing point caused an accident of misoperation of the equipment,so the electromagnetic compatibility research of the power cabinet merge unit is imminent.This article studies the principle of electromagnetic compatibility and the IEC61000-4electromagnetic compatibility test technology standard.It describes the role and functional characteristics of the power unit merger unit in active electronic transformers.According to the S.A.Schelkunoff electromagnetic shielding theory,the near-field shielding,The reflection loss and absorption loss characteristics of near magnetic field shielding,low frequency magnetic field shielding and discontinuous shielding,through the selection of appropriate shielding materials,optimization of heat dissipation holes,optimization of plug-in panel gaps and optimization of chassis profile structure.Conducted electromagnetic shielding design.And through the pilot test data to verify the effectiveness of its optimization.For the prototype of Xuji DMU-831 merged unit,the electromagnetic fast interference transient immunity,the surge shock immunity,the electrostatic discharge immunity and the conducted emission exceed the standard.Phenomenon,this article combines the electromagnetic compatibility principle and the IEC61000-4 electromagnetic compatibility test technical standards,waveform and characteristic analysis of these four kinds of electromagnetic compatibility test,according to its characteristics and the path of electromagnetic wave coupling into the loop,put forward corresponding rectification measures,cut off The propagation way of electromagnetic wave,thereby reducing the chanceof electromagnetic wave coupling into the loop,and finally verified the feasibility of the corrective measures through the experimental data.