Cooperation capacity optimization of wind power and thermal power based on Cournot model

In wind-thermal-bundled DC transmission system, plants of wind power and thermal power in the sending end, which have mutual influence on the planning of power capacity, belong to different stakeholders. This paper takes the existing renewable energy policy and the operation characteristics of wind farm and thermal generator into account, and the profit models of wind power supplier and thermal power supplier are respectively established according to different strategies of cooperation or non-cooperation based on game theory, to simulate the decision making of the two power suppliers. When the two both take non-cooperation strategy, a Cournot model which assumes that one can develop its optimal capacity planning strategy through estimating the rival’s response is established to obtain the Nash equilibrium, so as to maximize their profits respectively. Besides, the objective changes into maximizing the suppliers’ total profits when they choose cooperation strategy, and the optimal capacity is calculated. Meanwhile, the influencecoefficient which can illustrate the variation of one’s profit influenced by the changing of the other’s strategy is introduced, and based on which the profit distribution plan is presented. Moreover, a case is carried out for a wind-thermal-bundled DC transmission system, and the result shows that wind power supplier holds the active position in the game while the thermal power supplier holds the passive position. In addition, the study of this paper can provide the participants of new energy capacity planning with a basis to make decision.