The Optimization Of Hybrid Power System Based On Improved Mixed Integer Linear Programming

Every significant change in the world economy is closely linked to the changes in energy sources demand.With the successful transmission of high-voltage,long-distance in electricity,it will make the industrialization developing never limited by geographic location any more.Recently,due to the depletion of fossil energy sources and explosion of global environment problems which caused by improper usage,the call for effective exploitation and utilization of renewable energy sources is becoming high.Especially since 21 st century,the renewable energy sources such as wind,hydro and solar power are developing very fast,and the historical transformation of energy demand is gestating quietly on a global scale,renewable energy sources are much more superior to fossil energy sources in the sustainable development of the global economy.According to some related works,renewable energy sources must be converted into electricity for efficient usage.Therefore,the research on the optimal operation of hybrid power system is of great significance.At the same time,in order to ensure the security,reliability and economic operation of the power system,network security constraints are also indispensable.This paper is concentrated on the optimization of hybrid power system considering security constraints.The main work has been done is as follows:(1)Analyze and discuss the reasons comprehensively that affect the stability of generation by renewable energy sources,and establish a probability distribution model.Then,using the Latin hypercube sampling method to predict the possible scene of wind power generation.In addition,the k-means clustering method is used to classify the scenes with similar features,and select the representative scenes to reduce the computational complexity of the model while maintaining accuracy.(2)The experiments simulation are carried out in three parts: optimal scheduling of traditional unit commitment problems;optimal scheduling of unit commitment problems considering renewable energy sources complementation and optimal scheduling of unit commitments problems considering security constraints in hybrid power system.In addition,as a representative of the energy storage system,the pumped-storage power plant can not only improve the power quality but also ensure the stability of the power system.Two important components are quantitative analysis,while considering security constraints,providing a theoretical basis for efficient and high-quality operation of hybrid power complementary system.(3)Due to the increasing scale of systems brings a great burden on mixed integer linear programming,a large scale of system make a higher requirement on the efficiency of algorithm.This paper proposed an improved mixed integer linear programming model based on symmetry breaking constraints for solving unit commitment problems in large scale of systems.Then there is a comparison on the proposed approach and traditional approach.Numerical experiments have been conducted by changing the scales and convergence precision of the system,the results demonstrated that the proposed approach is superior to others in optimal value and time cost.