Bi-Level Optimal Scheduling of Distribution Networks with the Photovoltaic Prosumer Groups Based on Contract Theory

Large-scale development and grid integration of distributed photovoltaics (PV) are crucial measures for optimizing energy structures and building a new type of power system. Aggregating PV prosumers to form a PV prosumer group enhances their competitiveness in the market. The introduction of contract theory addresses the asymmetry in information exchange between the prosumer group and individual prosumers, motivating active participation in the active power market. Therefore, this paper proposes a bi-level optimal scheduling of distribution networks with the photovoltaic prosumer groups based on contract theory. The upper layer establishes an optimization dispatch model between the distribution network and the prosumer group, aiming to minimize the operating cost of the distribution network. This is achieved by incentivizing the prosumer group to respond actively to the system's active power demand through electricity pricing. The lower layer establishes a contract model between the prosumer group and individual prosumers. The prosumer group responds to the distribution network's electricity prices and updates the contract terms based on contract theory, thereby encouraging prosumers to participate in the market. Prosumers optimize their own electricity purchasing and selling strategies according to the contract terms, fully exploiting their active resource potential. Finally, comparative scenario examples are set up in the IEEE 33-node system to verify that the proposed method motivates prosumers to actively participate in the market, promotes the local balance of active power, and enhances the economic benefits of the distribution network, the prosumer group, and individual prosumers.