Research Of Distribution Network Planning With Distributed Generation

Compared with the traditional power generation equipment,the distributed power generation equipment has the characteristics of high utilization rate,high grid voltage stability,low construction cost,less environmental pollution and transferring peak load.But the distributed power generation must be a scientific access to the grid,if the distributed power generation access disorder,it will result in the damage to power grid,the degradation of power quality,voltage instability and security degradation and other issues.Distributed power supply is usually connected to distribution network.There are many uncertain factors that influence its function.There are various loads with large quantities in the power grid and many loads can be randomly switched off and on,and the power grid connection mode is consequently changed.Affected by many uncertain factors,it is difficult to get all accurate information of the distribution system.Taking these uncertain factors into account,this paper studies the uncertain factors of load fluctuations and investment operating cost of the distributed generation in distribution system.The main content of this paper is as follows:(1)This paper gives a brief introduction to the basic definition and classification of distributed power supply and the difference between distributed power supply and traditional power generation technology.The uncertainty of distributed power supply accessing traditional grid is analyzed under the condition of uncertain distributed generation technology,from the perspective of distributed power project investment,in the form of interval numbers,this paper establishes the interval multi-objective optimization programming model with the objective of the distributed generation cost function and the network loss function.(2)In this paper,interval forward-backward power flow and imprecision-propagating multi-objective evolutionary algorithm(IP-MOEA)is introduced,and considering the lack of elite selection strategy and cross mutation operation in IP-MOEA method,the model has been improved.The improvement process is mainly to replace the elitist selection strategy and cross mutation operation with the selection strategy based on reference line in order to solve the shortcomings of IP-MOEA algorithm,such as premature,and carry out the simulation analysis taking four ZDT test functions as an example.The results show that the improved IP-MOEA method is superior to the unmodified IP-MOEA method on the best super-volume measure,uncertainty measure and CPU time.(3)The interval multi-objective optimization programming model is solved by the improved MIP-MOEA method and the interval forward-backward power flow through IEEE33 and American PG & E69 node system.The results show that the DG optimal configuration model and the improved IP-MOEA algorithm are used to optimize the DG in the distribution network with distributed power supply,and the economic and technical optimization can be obtained.