New Means Of Calculation For The Optimal Coordination Sequence Of All Relays In A Complex Multiloop Network

According to the specialty of power network development for enlargement and complication, the CAD system for relay protection setting strives for the validity accuracy and efficiency to achieve the optimal purpose of coordination of setting.In the recent years, many scholars of the inside and outside country advance a series of arithmetics based on graph theory with reseach for the optimal setting coordination for current protection and distance protection in a complex multiloop network . the calculation for minimum break points set as stat for coordination of setting is the core of these arithmetics and large. The paper put forward to two new means of solution of MBPS. One defines break points based on node degree with comparing the amount of all backup protections in a mutiloop network. It is testified by practice to have legitimacy and feasibility with simple theory and improve efficiency a lot of protection coordination setting. The other classfies the calculation of MBPS into the solution of inequation based on heuristic knowledge of MBPS of optimal directional coordination setting in complex multiloop network and comes into equivalence of 0-1 integral second layout problem. On the basis of the principle of Gene Optimal Evolution, a new approach to determine MBPS is first presented and decreases the computational complexity of MBPS problem.Based on functional dependence of relation algebra, the paper available expresses the coordination relation between primary and backup prection and it is FDS which can generate directed basic loops and form optimal coordination sequences of protection setting,andaccordingly achieve the optimal coordination of prections in the whole network..