Under the environment of energy internet, the power supply-demand market presents a more remarkable trend of smartness and openness. Meanwhile, the power suppliers also face a more diversified and competitive situation. Considering the competition and coexistence of multiple power suppliers in the open market environment, this paper analyzes the competitive behavior and interaction between single power supply entity and others different entities, and formulates the competitive game model among them based on a potential game. Meanwhile, a dynamic interactive electricity pricing strategy is designed to stimulate the interaction between users and power suppliers, with the goal of users-centered, market-oriented, maximizing satisfaction of market main bodies. Simulation results demonstrate that the proposed competitive model can help power suppliers to be more rational, and also can realize the efficient utilization of user-side controllable resources.