Study On Power System Restoration Considering The Constraints Of Substation Batteries And Traffic Networks

After the blackout of power system,it is of great significance to reduce blackout loss by reasonable and orderly restoration of power grid backbone.How to determine the target skeleton network and its recovery path sequence is the main task of grid reconstruction.During the process of grid reconfiguration,it involves the operation of a large number of generating units and no-load overhead lines.Due to the limited capacity of DC storage battery in the substation,the possible failure of the operation of transmission line may occur.As an ideal mobile power type suitable for large power outage,emergency power cars can deal with power outage in time according to capacity of the accident area and restore electricity of substations.Considering various time-factors affecting restoration process and the importance of load nodes during process of grid reconfiguration,it is imperative to develop a power system recovery plan that takes into account substation battery and traffic network constraints.Aiming at the limited operation capacity of DC storage battery in substation,grid reconfiguration phase is optimized in different periods after blackout.First of all,considering the optimization of unit recovery sequence and restoration path optimization,a power priority restoration grid reconfiguration scheme considering charging time constraints of substation battery is proposed to recover power capacity as much as possible.With machine start-up constraints and corresponding power constraints,the improved discrete wolf group algorithm is used to prove practicality and efficiency based on the simulation results of IEEE 39-bus system.This stage can restore most of startup power capacity,and establish part of grid.It provides a guarantee and foundation for next step into emergency power cars to complete follow-up substation and line charging.When battery of substations is completely depleted,the power outage of whole station cannot be operated.Therefore,emergency power cars should be introduced as an auxiliary recovery strategy for emergency single point recovery.At present,substations in our country can generally achieve unattended operation,and the corresponding operators need to be in place in the event of power loss.In this paper,a power system restoration scheme considering traffic network constraints is proposed,and a mathematic model of power supply route optimization with time window is established.Based on the possible traffic congestion in actual traffic roads,an evaluation system is established to evaluate the congestion degree of traffic network.Fuzzy algorithm gives congestion rating of each traffic road to amend emergency power cars route selection.Finally,the effectiveness and practicability of restoration scheme proposed are verified by using discrete monkey algorithm through IEEE30 node system and an actual network in China.The research work provides a new way to deal with the reconfiguration strategy of power system backboneincluding traffic network constraints.