Research On Widearea Protection And Channel Reconstruction Technique Coping With Power Grid Catastrophe

With the development of interconnected nationwide power grid, the traditionalprotection which is based on the local information exposed some problems. It has complexsetting principle, poor adaptability to grid operation change and is inclined to mal-operateunder heavily loaded flow transfer. Recent years, to improve the performance of thetraditional relay protection, the research on wide area protection has been widespreadconcern and achieved some results. On the other hand, the grid catastrophe triggered byextreme disasters have occurred, it is facing new challenges. Based on the study of “thelimited wide area intelligent protection response to grid catastrophe protection” which isNSFC, this paper studied the following aspects to cope with catastrophe: structure andcommunication network of wide area protection system and their adaptive reconstructiontechnique.The system structure is one of the important foundations for the implementation ofWAPR. Differences in the system structure will lead to different communication networkand scheme of setting up communication channel. Based on the concept of the limitedwide area intelligent protection, a regional centralized and distributed structure is proposed.The specific function of each unit in the system is introduced.Based on the regional centralized and distributed structure, a three-tiercommunication network of wide area protection based on MSTP is proposed. It usesMPLS technology and EOS mode to transfer data and forms the network by EVPL. Thispaper analyses the delay of communication network.When extreme disasters occur, the power communication may be interrupted. So it isnecessary to study communication channel reconstruction scheme. This paper studies itfrom two aspects. Firstly, a circuitous channel reconstruction scheme based on ant colonyoptimization is proposed using the normal communication channel. The simulation of thisscheme based on MATLAB shows its performance. Secondly, when there are notcircuitous channels, a novel communication channel reconstruction scheme based on wireless sensor network (WSN) is proposed. The simulation based on PSCAD/EMTDCshows the scheme of emergency communication channel reconstruction based on WSNcan satisfy the need of WAPR.Finally, the work of this paper is concluded and the further research directions arehighlighted.