The Research On Strategies Of The Microgrid With High Density Distributed Generations Integration

In order to cope with the global energy crisis and climate change,countries around the world are committed to the development of clean energy in recent years.And making full use of the distributed power supply is one of the ways to make use of clean energy.The access of high density distributed generation to micro-grid is one of the strategic options to solve the energy struct ure problem in China.Considering the distributed power of similar types of photovoltaic and wind power has fluctuation and randomness of power generation,it is likely to cause difficulties or power grid operation security and stability issues when the hi gh density direct access to the existing distribution network.And the micro-grid can not only better accept the distribution of power,as a result of its good controllability,the impact on the existing distribution network will also be very small.Resear ch on the way of the distributed power access to the microgrid and the stability of the microgrid after access become particularly important.In this paper,firstly,according to the difference of bus load characteristics,the micro grid is divided into different types of Group.The operation of micro-grid with Group as the unit can increase the anti-disturbance ability and the stability of the system.Then,the characteristics of the economic theory and the incomplete information power market are combined;considering the market demand,the elastic coefficient is introduced,and the Group pricing mechanism suitable for the access of DG to micro-grid is derived;According to the pricing mechanism of the group,the bidding strategy of the distributed power's access to micro grid is established,namely the distributed power to be accessed.According to the Group clearing price,the DG can access to grid in the case of guaranteeing the maximum profit of its own.According to the unique characteristics of the mic ro-grid system,the static stability index of the branch between any two nodes which is used to judge the static voltage stability of micro grid is deduced.We obtain the output of the distributed generation using Latin hypercube sampling.Finally,based o n the results of power flow calculation,the stability of the micro-grid is analyzed when the distributed generations with different permeability and density access to Group.Finally,simulation results show the high density distributed power and the effectiveness of the proposed Group micro-grid bidding strategy based on the stability analysis of the different permeability of DG Group micro-grid.