Research On Flexible Economic Dispatch Of Power System With Wind Power

The high penetration of renewable energy represented by wind power further exacerbates the fluctuation and randomness of net load.How to improve the consumption of renewable energy such as wind power is the key to the large-scale development and utilization of renewable energy under the premise of ensuring the safe and stable operation of power system.Power system dispatch flexibility representing system’s ability to cope with this uncertain changes has attracted increasing attention.However,for the optimal allocation of power system dispatch flexibility,there are still some problems,such as redundancy of adjustable capacity,insufficient availability in practical operation,incomplete consideration of flexible resources,etc.Therefore,it is of great theoretical value and practical significance to carry out research on flexible economic dispatch of power system with wind power.According to the definition and characteristics of power system dispatch flexibility,this paper firstly quantifies it from the perspective of "supply and demand balance",and uses scenario analysis to accurately describes the dispatch flexibility demand of wind power and load.Secondly,a two-stage flexible economic dispatch model of power system is established to solve the problems of redundancy and insufficient availability of the adjustable capacity allocated by existing research.In the first stage,the main problem of unit commitment and adjustable capacity allocation is solved according to the predicted value of wind power and load,while the adequacy of adjustable capacity allocation in the first stage is tested in the second stage according to the typical scenario sets of wind power and load.On this basis,in order to improve the dispatch flexibility of power system,demand response is used as a flexible resource to participate in the upward and downward adjustable capacity allocation of power system.Then,for the problem that demand response cannot significantly improve the downward dispatch flexibility of power system,it is further proposed that the power-to-gas equipment be used as a flexible resources.At the same time,considering the influence of natural gas system on the output and adjustable capacity of gas-fired units and power-to-gas equipment in power system,a flexible economic dispatch model of integrated power and gas systems considering both power-to-gas and demand response is established,and the slack variables are introduced to solve the model.Finally,the effectiveness and superiority of the proposed two-stage flexible economic dispatch model of power system,the necessity of coordinated optimization of the integrated power and gas systems,the advantages of demand response and power-to-gas equipment in improving power system flexibility and economy are verified by using the modified IEEE30 bus power system and 10 node natural gas system.