A Multi-objective Optimal Reconfiguration Research For Distribution Networks With PV

With the rapid development of the economy and the continuous improvement of people's living standards,the demand for electricity is also growing,and the traditional fossil energy is depleting.Under this background,the renewable energy represented by photovoltaics is widely distributed,clean and environmentally friendly.The advantages of flexibility and convenience are gradually increasing in the power grid.In recent years,distributed photovoltaic power generation has developed rapidly,and the installed capacity in China has continued to grow.However,the transmission capacity and peak shaving capacity of the distribution network are limited.In fact,the ability of the grid to dissipate distributed PV is relatively limited.The situation of distributed photovoltaics “issuing electrical energy but not being connected to the grid” has occurred,resulting in serious waste of distributed photovoltaic energy..Therefore,it is necessary to conduct in-depth research on how to improve the distribution network to dissipate distributed PV capacity.In order to improve the consumption rate of photovoltaics in photovoltaic distribution networks a new distributed photovoltaic strategy based on dynamic reconfiguration of distribution network is proposed in this paper.In consideration of the changes of load demand in each period,the uncertainty of distributed photovoltaic output and switching times,a multiobjective optimization reconfiguration model of distribution network based on the maximization of the photovoltaic ratio and the least switching times is established.In order to solve the uncertainty of photovoltaic output,the shortest confidence interval fast solution method according to the rectangular formula and the characteristics of photovoltaic output.This method can quickly calculate the shortest confidence interval of the Beta distribution at any confidence level,and solve the problem of inaccurate estimation of the photovoltaic power output error interval for the solution of the model;a new multi-objective index differential evolution algorithm is designed for solving the model,which combines the characteristic of the exponential function,that is,the concave function and the subtraction function into differential evolution algorithm,making the new algorithm achieve the effect of individual diversity and convergence speed.In order to verify the efficiency of the new distributed photovoltaic absorption model and multi-objective exponential differential evolution algorithm based on dynamic reconfiguration of distribution network proposed in this paper,the simulation of distributed photovoltaic access to IEEE-33 nodes is taken as an example.The simulation results show that the exponential differential evolution algorithm can effectively alleviate the contradiction between depth optimization and computational speed of the intelligent algorithm.This method can effectively improve the ability of distribution network to absorb distributed photovoltaics.