Research On Two-layer Optimal Scheduling Of Active Distribution Network Under Multi-time Scales

In response to the country’s call for vigorously developing clean energy,a large number of distributed power sources have been connected to the distribution network,which has improved the "hematopoietic capacity" of the distribution network.However,large-scale distributed power grid integration has changed the structure and performance of the distribution network itself,and its improper output will change the direction of the power flow,causing local voltages to be different from traditional distribution networks.If not controlled and managed,it will further damage the reliability of system power supply.In order to give full play to the advantages of distributed power grid integration and ensure the safe,reliable and high-quality operation of the distribution network,this paper conducts research on the two-level optimal scheduling model of active distribution networks under multiple time scales.This paper analyzes the characteristics of distributed power generation units on the "source" side of the active distribution network,electric vehicles on the "load" side,and flexible loads,and establishes a mathematical model for the distributed units and loads of the microgrid.Day-ahead optimal dispatching is carried out with grid-connected operation mode;based on this,a two-layer optimal dispatching model for active distribution network and microgrid under multiple time scales is established.The improved differential evolution algorithm is used to solve the lower-level model,and the chaotic anti-learning population initialization and the adaptive adjustment of control parameters are introduced,thereby preserving the diversity of the population and accelerating the speed of population convergence.The results show that the improved algorithm has strong global search ability and convergence,and it is not easy to fall into the local optimum.Finally,taking the improved IEEE33 node calculation example as an example,the CPLEX solver and the improved differential evolution algorithm are used to program and simulate the two-tier optimal scheduling model of active distribution network.The simulation results verify the active power distribution in multiple time scales proposed in this paper.The double-layer optimal dispatch strategy of the grid can significantly reduce the operating cost of the distribution network,and realize the optimal dispatch of the active distribution network and the microgrid.