| The deterioration of environmental problems has made microgrids integrated with distributed renewable energy power generation more and more attention.It is foreseeable that large-scale microgrid(MG)access to the distribution network to participate in operation has become an inevitable trend in the development of the distribution network.In the future,microgrid systems of source/storage/grid/load will be seen everywhere in the distribution network,which will play an important role in improving the consumption of distributed renewable power and improving the reliability of the system.However,there are many types and different forms of microgrids.Their high penetration keeps the operation of the distribution network constantly changing,which poses a challenging problem to the reliable and safe operation of the distribution network.Based on this,this paper studies the related issues of the rapid evaluation of the operation reliability of the distribution system with high penetration rate microgrid.The main research contents are as follows:(1)The method for quickly dividing distribution network islands with high-permeability microgrids considering the consumption and reliability of Distributed Generotors(DGs)is studied.First of all,considering the maximum utilization of DGs,based on deep search and "power circle" theory,conduct network topology analysis on the distribution network,determine the candidate area of islands,and then determine the set of candidate islands based on important loads and power balance.At the same time,in view of the dilemma between the formation of a single island or the formation of a joint island in the process of island division,the reliability of the microgrid with multiple DGs and the overall reliability of the multimicrogrid system are analyzed and established.On this basis,based on the improved imperial competition algorithm,the optimal island division is realized through the reliability and voltage loss competition between candidate islands,and the parallel strategy of the proposed island division method is realized based on the multi-core CPU.A large number of simulation examples analyze the applicability and efficiency of the proposed method.(2)Research on the rapid evaluation method of the operation reliability of the distribution system with high penetration microgrid based on the equivalent technology.Based on the analysis of the three influencing factors of component aging failure,weather conditions,and accidental failure,a time-varying comprehensive failure rate model of components is established based on Bayesian.The multi-state probability model of wind turbine and photovoltaic power generation system combination is established by means of mean shift clustering and Markov chain.Combined with the network topology,the distribution network with high penetration rate microgrid is equivalently treated based on the equivalent technology,and it is equivalent to the equivalent microgrid and the equivalent load group,and based on the principle of minimum path method,etc.Effective network failure rate index.Combined with the minimum path method,an efficient and fast operation reliability evaluation method based on multi-core CPU is proposed.Through the simulation comparison and analysis with the traditional minimum path method,the correctness and efficiency of the proposed method are verified.(3)The rapid evaluation method of the operation reliability of the distribution system with high permeability microgrid based on feeder partition and fault tree is studied.Based on the classification and division of distribution systems containing high-permeability microgrids based on the principle of feeder division,considering the aging failure of equipment,weather conditions,and accidental failure,the failure probability of different divisions is obtained based on the equipment failure probability and the fault tree analysis method.At the same time,through the analysis of the operation status of the distribution system with high-permeability microgrids,the health status index of the distribution system is proposed,and the system operation health status is classified based on the health status index.On this basis,the probabilistic evaluation of the health status of the distribution system with high-penetration microgrids is carried out considering the correlation between the partitions,and a parallel strategy is implemented based on the multi-core CPU design to achieve rapid evaluation.Through a large number of simulation comparison analysis with existing methods,the rationality and efficiency of the proposed evaluation method are verified.(4)Designed and implemented a rapid evaluation system for the operation reliability of the distribution network with high penetration rate microgrids.According to the research content,Matlab R2014a software is used to program the proposed method,and html,css and js in the Python web development technology are used to design the system interface.And use python to call Matlab script function to realize the above functions,thus completing the design and development of the system.The system function modules mainly include four modules:user management,related technology introduction,island division,and quick evaluation of operational reliability. |
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