The rational use of demand side response can improve and optimize the economic operation level of distribution network and reduce the network loss. The characteristics of medium-and long-term demand response and short-term demand response are studied

and a loss optimization method based on demand-side response model with multi-time scale is proposed. Particle swarm optimization( PSO) is chosen as the optimization algorithm. Based on the compiled power flow calculation program after adding certain constraints

the IEEE 30 node distribution network is analyzed and the simulation results show the feasibility and effectiveness of the proposed method based on the demand-side response model of multi-time scale.The research mainly provides a new idea for the optimization method of network loss

which is helpful to improve the economic efficiency of electric power enterprises.