Planning And Operation Optimization In Power Systems With Integrated Wind Power

Wind energy is a kind of abundant and environmentally friendly renewable energy sources,and wind power is of great significance to alleviate the pressure of energy supply and promote the social and economic development of human beings.However,the uncertainties and volatility of the wind power output present new challenges for power system planning and operation.On the other hand,with the increasing proportion of gas consumption and the emergence of power to gas(PtG)technology the coupling degree between a power system and a natural gas system tends to strength,and hence it is necessary to examine the impacts the interconnected natural gas system on power system planning and operation.Morover,demand side management(e.g.,orderly utilization of power)is becoming an increasingly important measure for ensuring secure and reliable power system operation.With the above mentioned background,this dissertation examines some issues related to planning and operation optimization in power systems with wind power integration.The detailed contents of this dissertation are as follows:1)Analysis of wind power development status and key technology for enhancing the capability of accommodating wind power.First,the current situation of wind power industry development is summarized.On this basis,the future development trends of power systems from the energy structure and energy network integration are studied,and the challenges of future wind power accommodation are summed up.In view of the challenges,existing research work on interconnected electric power and gas systems is reviewed from the perspectives of uncertainty factors,system modeling,energy flow calculation,collaborative planning and operation of these two systems.Finally,the research framework of wind power accommodation considering the future development trend of power systems is presented and key technical fields outlined.2)A collaborative siting planning method of wind farms and power-to-gas plants based on scenario analysis.It is assumed that renewable energy(wind power)generation company lead the co-investment of wind farms and PtG plants.First,the mathematical model of a PtG plant is developed based on its technical features.Then,the collaborative site selection planning model based on scenario analysis is established,aiming to maximize net investment income.Moreover,a density clustering algorithm is introduced in scenario optimization in order to generate typical wind power generation scenarios.Numerical results of case studies show that this method can improve the economic efficiency of the investment scheme and reduce wind power curtailment.3)A multi-objective operation optimization method for interconnected electric power and gas systems with wind power acoomodation.First,a multi-objective operation optimization model is established by minimizing the operation cost,wind power curtailment cost and energy loss of interconnected electric power and gas systems.Then,nonlinear constraints in the model are simplified by piecewise linearization,and the original mixed integer nonlinear planning model is then transformed into a mixed integer linear planning one.Moreover,the multi-objective optimization technique based on the augmented ?-constraint method is employed to solve the model,and the pareto optimal solution is attained as the optimal compromise solution by fuzzy comprehensive evaluation.Numerical results of case studies show that the proposed method can reduce wind power curtailment as well as energy loss of the network while minimizing the operation cost of the whole system.4)A scheduling method for peak load shifting based on hybrid multiple-attribute evaluation.Significant volatility of wind power outputs may lead to the occurrence of emergency power outage,so it is necessary to interrupt power supply to less important users when the total power supply cannot meet the overall demand.Thus,an important issue to be addressed is how to properly prioritize the electricity use of users,and that is the so-called orderly power utilization ranking problem.First,in order to handle different types of data in the orderly power utilization ranking problem,with special emphasis on peak load shifting,an evaluation system considering the economic benefits,social impact and environmental influence is put forward.Then,a hybrid multiple attribute decision-making method is adopted to calculate the mixed-data dominance of each electricity user under a specified index.Moreover,the comprehensive weight is attained on the basis of calculating subjective and objective weights,and the weighted closeness degree of each electricity user obtained to rank the sequence for orderly power utilization.Numerical results of case studies show that this method can effectively solve the multi-attribute decision-making problem with inconsistent forms of information,and provide decision support for secure and reliable system operation.