The Optimal Configuration Method Of Reactive Power Equipment For Distribution Network Considering The Influence Of The Microgrid

In recent years,under the dual impetus of national policy and market capital,distributed new energy and micro-grid with new energy have developed rapidly in distribution network,which makes the structure of distribution network much more complex.At the same time,the uncertainty of new energy and load further increases the difficulty of operation and control of distribution network.With the increase of new energy penetration,voltage off-limit and voltage flicker are prone to occur.The reasonable reactive power planning and the optimal operation strategy of reactive power equipment are urgently needed to adapt to the new changes of distribution network,to ensure the quality and safety of power consumption,and to promote the permeability and further development of new energy.In this paper,the micro-grid-connected distribution network is taken as the research scenario,which provides a new planning idea and method for reactive power optimal allocation of distribution network after new energy grid-connected.The specific research work in this paper is as follows:Firstly,the development of microgrid at home and abroad and the research status of reactive power configuration in distribution network are introduced.The development history of microgrid in various countries is briefly described,and the research result and development direction of microgrid in China is analyzed.Combined with the current research direction and emphasis of reactive power optimization,the main problems and new requirements of reactive power optimization research before the development of stochastic distributed generation and micro grid are summarized.The significance and objectives of this study are determined.Then,a general model of microgrid for maximum profit is proposed.Considering the characteristics of power supply and energy storage output,operation cost and market price mechanism in microgrid,and aiming at economic optimization,a general strategy rule of microgrid power generation control is constructed.Combined with weather and seasonal factors,a probabilistic multi-scenario output model of microgrid grid grid-connected load is established.The research lays the foundation for follow-up.Finally,an optimal configuration method of reactive power compensation equipment for coordinated planning configuration of switchable shunt capacitor bank(C)and static var generator(SVG)is proposed.Based on the grid-connected scenario of microgrids,a bi-level optimization programming model for the coordinated configuration of dynamic and static reactive power equipment is established.The upper model takes the sum of the total life cycle cost(LCC)of equipment and the operation cost of power grids as the objective function,and optimizes the configuration mode of reactive power compensation devices.The lower model takes the minimum operation cost as the objective function,optimizes the operation mode of capacitor banks.The improvement genetic algorithm is used to solve the model.The effectiveness of the model and method is verified by a modified IEEE33 node as an example.The simulation results show that this method can effectively improve the qualified rate of voltage and reduce the loss of power grid.To sum up,it has good economic benefits.