Research On Energy Management And Optimal Operation Of DC Distribution System

DC distribution system is characterized by good controllability, low loss, high power quality and large transmission capacity, it is suitable for multipoint access of distributed generations, and it is the new direction of distribution system. So it has been given more attention in recently years. Reasonable and effective energy management and economic operation technologies can improve the economical efficiency and practicability of DC distribution system significantly and facilitate DC distribution system development.In this paper, achieving energy management and optimal operation of DC distribution system is the major research objective. Firstly, the current development situation and prospect of DC distribution system was introduced, the control technology and power flow calculation of DC distribution system were analyzed, then the architecture of energy management system for DC distribution system based on multi-agent technology was proposed. Then on the basis of determining the steady-state model of the main unit in DC distribution system, the optimal scheduling model which contains economic costs, environmental costs, net loss costs and a variety of constraints has been established, and the corresponding optimal scheduling strategy was proposed. Then an example was given, the simulated annealing based improved particle swarm algorithm (IPSO) was used to solve the example, the optimal results was analyzed, the economic operation was achieved, the correctness and effectiveness of the proposed optimization strategy has been verified. Finally, in order to reduce the impact of renewable energy uncertainty on DC distribution system and improve the ability to integrate renewable energy into DC distribution system, on the basis of the short-term power forecasts and ultra-short-term power forecasts, a multi-time scales-based optimal scheduling model was established. The optimal scheduling was divided into two stages:day-ahead optimal scheduling and real-time scheduling, and the optimal scheduling error caused by uncertain renewable energy can be reduced through the coordination and optimizing of the two stages, then the safe, reliable and economic operation of DC distribution system can be achieved. A specific example of the model was solved, the optimal results showed that the model can reduce power fluctuations and ensure economic operation of the system in actual operation. The correctness and effectiveness of the proposed multi-time scale-based optimal scheduling model has been verified.