Research On Models And Methods Of Adequacy Decision For Power System With Wind Power Integrating

With the integration of large-scale wind power, new problems arise from electric power system planning and operation decisions based on the traditional power system reliability theory. Reliability of power system includes two aspects, namely, adequacy and security. Adequacy of an electric power system is defined as the power and energy supply capability of power system for the user in the allowable ranges of components rated capacity, bus voltage and frequency considering planned and unplanned outage of components under the condition of power system steady-state operation. Different from traditional power, the characteristics of wind power such as inverse peak-regulation, randomness and intermittent output result in the complexity of decision about adequacy. Although the integration of large-scale wind power improves the power structure in the sense of energy saving and emission reduction, there is still optimization space in decision about adequacy safeguarding, and uncertainty of adequacy on transmission section increases, too. In order to provide decision-making tools for adequacy safeguarding, adequacy decision-making models and methods were researched around the optimization problems such as construction timing of clustering wind farms, transmission reliability margin and capacity benefit margin on the transmission section in the interconnected power system. In the current situation of developing wind power at home and abroad, research in this paper has not only academic value but also important practical significance.Main research work and innovative achievements obtained in the paper are as follows:In order to ensure the adequacy of peak regulation capacity, timing planning thought, models and methods of wind farms were proposed. Taking the correlation of wind speed and coordination of construction time into account, the relationship between investment and operation of wind farms and conventional units was depicted with investment timing matrix and operation state matrix. The index of value at risk (VaR) of peak-load regulating capacity vacancy was presented to measure the adaptability risk and risk assessment method considering correlation of wind speed was proposed. The value of options portfolio was introduced to measure the economy of investment timing of clustering wind farms, and economic value evaluation model was established considering the learning effect. Based on the above study, bi-level programming model was built to realize the organic unity of investment economy and adaptability risk of peak-load regulation and risk equivalent coefficient was introduced to endow the penalty factor with definite techno-economic significance. Mixed algorithm of Monte-Carlo simulation and genetic algorithm was proposed to solve the above model. The study results on IEEE30test system shows that the proposed models and methods are feasible and effective.Generalized insurance theory was applied to develop a new TRM decision model suitable for interconnected grid with wind power integrating. In order to measure the generalized reliability and economy, the concept of TRM virtual insurance was put forward. And by application of this concept, the problem of optimum TRM decision was reconstructed into the problem of optimum purchase decision of virtual insurance. With the introduction of utility function, reliability preference was indirect described. Optimum purchase decision model was proposed on the basis of theory of assets choice, and Monte-Carlo simulation method was used to evaluate the model parameters. A case study of IEEE30bus verifies the effectiveness and advantages of the model proposed.To adapt to the new characteristics of the decision-making problem of capacity benefit margin for interconnected system with wind power integrating, methods and models based on option theory were proposed. Reliability value of generation reserve increment was researched, and the concept of virtual reserve increment option was put forward. The problem of CBM decision was brought into the analytical framework of optimum purchase decision of options portfolio, so that multiple factors influencing decision could be given all-round consideration effectively. Due to the exotic characteristics of reserve increment options, such as trigger conditions, times and order of execution, value evaluation of options portfolio encountered difficulties. Due to the exotic characteristics of reserve increment options, such as trigger conditions, times and order of execution, value evaluation of options portfolio encountered difficulties. A case study of modified IEEE-RTS79verifies the effectiveness and advantages of the model proposed.Coordination strategy of adequacy resources is necessary to safeguard the adequacy of Electricity Power System with Wind Power Integrating. Under the concentrated mode of large-scale wind power integration, from the viewpoint of delimitating and identifying flexible adequacy resources, the basic idea and method were proposed that flexible adequacy resources in the links of power generation, transmission, distribution and consumption should be coordinated so as to promote digestion of wind power. Comprehensively considering technical characteristics of various power generations and such constrains as the balance of power, thermal loads and transfer capacity, a model was built to analyze wind power accommodation capacity of power grid. Taking a certain province in China, which is rich in wind power resources, as calculation example, the changes of wind power accommodation capability were simulated and analyzed under different scenes of introducing in different flexible resources. Results of simulation and analysis show that the accommodation capability of wind power can be improved by increasing various flexible resources in which the resource of peak load regulation capacity plays the most important part.Under the scattered integration mode of wind power via micro grid, the concept of 'island-shaping ability' was put forward to describe the'mutual-aiding effect', and its calculation method was also proposed. Considering the'mutual-aiding effect', a distribution network flexible planning model containing MG was established. Improved bacteria colony chemotaxis (BCC) algorithm was applied to solve the above model. Sigmoid function was adopted to solve the Boolean dilemma and the judgment and recovery strategy for the infeasible solutions arising from the iterative process was presented, which was based on operon theory and could repair the islands, isolated chains and rings simultaneously. IEEE54example shows the applicability of the model, and the effectiveness and feasibility of the improved BCC algorithm in the distribution network programming containing MG.