Research On The Adaptive Busbar Differential Protection

Power busbar is an important equipment in the electrical power system, its safety running relates weather the whole electrical power system can run steadily. Therefore the protective measures to the busbar appears especially importantly; As a result of the busbar own characteristic and the electrical power system complexity, the reliability of the existing busbar differential protection still by far is smaller than the differential protection on the line application. In view of this point, this article is to unify the present existing busbar differential protection criterions, and to design a new adaptive busbar differential protection with better performance and based on the DSP platform.After analyzing the advantages and disadvantages of the domestic and alien current differential protection criterions, paper design an integrative criterion bases on the fault current characteristic after the breakdown. This criterion combines existing differential protection criterions and makes different criterions part work in different time after fault. Among them, the way using the voltage,operation mode adaptability and the choice of fault busbar are innovation in this paper.The software design is an important part in system important. Generally, software reliability includes protection principle accuracy, logical organization strictness, computational method accuracy and stability. Based on the engineering project, paper has carried on the design to DSP platform software as well as protection software, and has carried on the actual programming and debugs to realize the software function.Finally, the test result indicated that the adaptive busbar differential protection in this paper is one kind of quite ideal protection. It can real-time change protection criterion according to the change of busbar movement and fault station to enables its protection performance to achieve superiorly.