The Application Of Interactive Energy Technology In Active Distribution Network Congestion Management

With the development of new energy distributed generation and the controllability of flexible loads,the traditional distribution network has gradually shifted to the active distribution network.In the traditional distribution network,the load is uncontrollable.When scheduling,only the power generation plan of the system can be adjusted to follow the load change.In order to satisfy a certain system margin when the system peaks,it is necessary to increase the total installed capacity of the system,resulting in a large overall system redundancy and poor economy.Compared with the traditional distribution network,the active distribution network emphasizes the interaction balance between source and load.Therefore,in the active distribution network,based on the interactive energy technology,the electricity price is used as the interactive information.On the one hand,it can reflect the balance of supply and demand in the power market,and on the other hand,it can reflect the congestion status of the distribution network.Compared with the conventional direct load control method of the traditional distribution network,this interactive technology can not only improve the efficiency of power usage,but also ensure the satisfaction of the user's power consumption.Based on the power background of the continuous improvement of distributed resources in the active distribution network and the continuous advancement of the power market reform,this thesis considers the congestion caused by the large-scale distributed generation unit access and improper flexible load dispatching.The impact can not be ignored.For the problem that the blocking management method studied at this stage has not effectively solved the problem of node voltage over-limit,this paper has constructed distribution system operator,multiple aggregators,and photovoltaic,electric vehicles,building air conditioners,energy storage systems,etc.This thesis proposes a day ahead and real-time two-stage congestion management model for active distribution networks considering both line capacity and node voltage over-limit.The congestion management model adopts a distributed algorithm.In the day ahead stage,each aggregator predicts the power consumption of the flexible load the price of the electricity the output of photovoltaic,while minimizing the power consumption demand.Then,the aggregator and the dso exchange the information of congestion to formulate a day-ahead trading plan;in real-time,each aggregator adjusts the deviation of the day-to-day transaction based on a more accurate prediction of the PV output and a change in the demand for flexible load power.Finally,the simulation results are verified with the IEEE33 node example.The results show that the proposed congestion management model can effectively solve the problem of the active distribution network in the current and real-time phases,and can ensure the line capacity and node voltage in the safe range are allowed in the distribution network.