Research On The Optimal Allocation Of Distributed Generation In Distribution Network

At present, the shortage of energy and environmental pollution are the two problems that are urgently needed to be solved in the world, the use of new energy power generation technology has become an effective measure to solve the two problems. Advantages of distributed generation are mainly reflected in reducing environmental pollution and improving power supply reliability and the power quality of the terminal users and meeting the sustainable development and so on. Combining new enerage power with the traditional power grid can make full use of the existing equipment resources through the coordination of the two complementary, it is considered as the best way to provide users with reliable and quality power, and it also is the new trend in the development of power industry.China and other countries in the world have made long-term planning of distributed generation, while the proportion of distributed generation in power grid is increasing year by year. Because of the influence of climate, geographical conditions and other factors, the output power of distributed generation such as wind and photovoltaic power is random. When the Network connects with a lot of distributed generation, it will bring great impacts on the grid, such as:change in power flow, influence on relay protection etc, and the impact is closely related with the allocation scheme of distributed generation. The rational allocation of distributed generation not only can make full use of natural dispersion energy, but also effectively improve the quality of power and the system load’s rate etc. Otherwise, it may increase the power loss of Network, lead to some nodes appearing low voltage or over voltage, change the fault current magnitude, direction and duration also. Therefore, it is very significant to research the rational allocation scheme of distributed generation.This thesis researches on the basis of relevant research achievements, it introduces main types and the characteristics of distributed generation and the impact on the power grid with distributed generation. Because the allocation scheme of distributed generation involves power flow calculation, so the node model of a variety of distributed generation and the way to handle was studied. This thesis introduces mathematical models of various distributed generations in power flow calculation. The node model of and the approach of various distributed generations The model for optimal allocation of distributed generation is established, the model regards the minimum operation cost as objective function, and considering the environmental benefits of distributed generation. Various constraints in the form of punishment factor were joined in the objective function, then, IEEE33-nodes distribution test system as a example of distributed generation multi-objective allocating, and use the particle swarm optimization(PSO) to solve the model, the result shows that the allocation scheme of distributed power is beneficial, and it can improve the system economy and environmental protection at the same time.