Bidding optimization of aggregators considering safety check in a distribution network

With the integration of most distributed energy resources or loads managed by aggregators into the distribution systems, a deviation will be observed between the bids of the aggregators and the actual power output in the electricity market if the constraints of the distribution systems are not taken into consideration by the aggregators, which will bring deviation penalties. To this end, a bi-level bidding model is hereby proposed for aggregators considering the safety check of the distribution system. The upper level considers bidding to maximize the profit of each aggregator and introduces the safety check of the distribution system as the lower-level problem. To ensure the safe operation of the distribution system and reduce the power deviation of the bidding plan of the aggregator, the node voltage deviation, active power margin of transmission, and the bidding ratio deviation rate of each aggregator are taken as the optimization goals of the distribution system. Additionally, the data privacy of each aggregator is preserved by using the alternating direction method of multipliers to decompose a bidding problem of aggregators considering the safety check of the distribution network into subproblems solved separately and in parallel. Finally, the rationality and effectiveness of the proposed method are illustrated using a modified IEEE33-bus system.