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Optimization Allocation Of Microgrid Considering Economic Dispatch And Its Improved Algorithm

Posted on:2016-12-14Degree:MasterType:Thesis
Country:ChinaCandidate:W ZhangFull Text:PDF
GTID:2272330470983157Subject:Electrical engineering
Abstract/Summary:PDF Full Text Request
With the smart grid becoming the focus of current study, micro grid as one of the main functions in smart grid is increasingly widely applied in power systems, and the optimal allocation of microgrid has become particularly crucial.In this paper, we set up mathematical models of wind turbine generators, photovoltaic arrays, batteries and diesel generators. Considering microgrid daily fixed cost of investment, the system power loss and energy waste loss, we take the daily total cost of investment as the objective function and genetic algorithms is used to solve this problem.Then, this paper adopts bilevel planning method to research the optimal allocation and economic dispatch of a microgrid by comprehensive consideration of three indexes of reliability, economy, and resource utilization, as well as environmental benefits. The upper level is the optimal allocation, which aims at minimizing the daily fixed cost of investment (DFCI), load loss probability (LLP), and excess energy rate (EER). The lower level is the economic dispatch, which aims at minimizing the cost of operation and management (COM) and cost of pollutant disposal (CPD). Considering the different dimensions of multi-objective functions of the upper level, a hybrid weighted method based on the judgment matrix method and variation coefficient method is proposed. For the objective function of the lower level, the penalty function method is adopted to handle the unbalanced active power. We propose an improved adaptive genetic algorithm (IAGA) to solve the objective function under the upper level and the lower level. With the example system, we test the stability and convergence performance of IAGA and analyze the optimal allocation scheme under different planning models. We also contrast the two different scheduling strategies of the microgrid and discuss the state of charge (SOC) of batteries. At last, the relationship between DFCI and LLP is analyzed.Finally, the comprehensive evaluation index system (CEIS) of four hierarchies is established and the calculation methods of the third level indexes (TLI) are presented, basing on various impacts of connecting distributed generation to the distribution network. This paper puts forward an improved triangular fuzzy number analytic hierarchy process (ITFNAHP) to weight the first level indexes (FLI) and the second level indexes (SLI) by consideration of uncertainty, and calculates the variation coefficient to weight the third level indexes (TLI). We calculate the comprehensive weight coefficients based on the weight coefficients of the FLI, SLI and TLI, and then calculate the comprehensive evaluation of satisfaction of different access schemes.
Keywords/Search Tags:Microgrid, Optimal allocation, Bilevel planning, Improved adaptive genetic algorithm, Comprehensive evaluation
PDF Full Text Request
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