Research On Cooperative Load Dispatching Strategy For Active Distribution Network

Traditional distribution network is a kind of passive network.It has no power supply and lacks regulation means.It is only responsible for transmitting electric energy to users.The rapid development and wide application of distributed generation technology has brought enormous challenges to the operation of distribution networks.On the one hand,the penetration of new energy in distribution network is increasing year by year,and the local absorption and utilization of renewable energy become the key to the operation of distribution network;on the other hand,the application of various new electrical equipment in the grid,the sensitive load in the grid is constantly increasing,and users’requirements for power quality and power supply reliability are getting higher and higher.However,due to the volatility and reverse peak regulation characteristics of large-scale photovoltaic and wind power,the peak-valley difference of power load is further increased,and the regulation and operation of power grid is challenged.Therefore,how to find a new way of regulation and control to achieve the coordinated control of the distribution network load is of great practical significance for the safe and reliable operation of the distribution network.This paper mainly studies the scheduling and control strategy of adjustable flexible load for distribution network with wide access of renewable energy such as wind and light.Emphasis is laid on the study of electric heat storage boiler and battery energy storage participating in distribution network dispatching.Firstly,the load characteristics of active distribution network are analyzed,and the load dispatching model of electric heat storage boiler and battery energy storage is studied.A coordinated optimal load dispatching model of distribution network is proposed,and the intelligent solution method of the above optimization model is studied.The main work of this paper includes:(1)On the basis of considering the uncertainty of renewable energy,the load characteristics and typical characteristics of active distribution network are analyzed.and the impact of large amount of renewable energy access on the load characteristics of distribution network is studied,which provides a basis and reference for the feasibility of load participation in coordinated dispatching.(2)The working principle and controllable characteristics of electric storage boiler and battery energy storage are analyzed,and the mathematical model of electric storage boiler and battery energy storage for load dispatching is established.The model can be applied to load co-dispatching of active distribution network with adjustable load,which provides a basis for establishing load co-dispatching model of active distribution network with adjustable load.(3)A load coordination dispatching model of active distribution network with adjustable load is established.Aiming at suppressing load fluctuation and reducing network loss,a multi-objective optimization method is proposed for the participation of electric heat storage boilers and battery energy storage in peak-shaving and valley-filling control of power grid.(4)A strategy for solving load coordination dispatching optimization model of distribution network with flexible adjustable loads based on particle swarm optimization and genetic algorithm is proposed.By comparing and analyzing the optimization results of the two algorithms.the validity of the two intelligent algorithms in solving the above-mentioned load coordination dispatching model is verified.The results show that the adjustable load can effectively participate in the distribution network load coordination dispatching,and realize the functions of peak shaving and valley filling.