由于负荷中心与可再生资源在地理位置上分布的不均匀，更大范围的资源合理配置需要跨区输电，而随着电力市场的深化发展，参与跨区电力市场出清的发电商将可能出现通过合作博弈策略行使市场力以争取自身利益最大的行为，此举可能导致跨区输电通道利用率降低，进而影响线路准许收入的稳定回收。为应对上述问题，提出了一种电力市场环境下考虑参与跨区出清的区外发电商合作博弈策略的跨区输电电价三层优化模型，上层为以准许收入稳定回收为目标的输电电价优化模型，中层为由区外发电商组成的跨区出清利益联盟的以联盟收益最大为目标的报量决策模型，下层为计及区外发电商参与的区内电力市场出清模型。为求解所提三层模型，采用了一种改进列和约束生成算法（C & CG）算法，将模型分解为主、子问题迭代求解，其中对于作为双层模型的主、子问题采用卡罗需-库恩-塔克条件（KKT）和大M法转化为等效单层模型后进行求解，而主、子问题模型中的双线性项则采用强对偶定理及变量离散参数化的方法进行线性转化以便于求解。最后通过PJM-5节点系统验证了所提三层优化模型能较好地体现区外发电商因合作博弈策略组成的跨区出清利益联盟的策略性决策和市场力行为，令输电电价的制定能在考虑区外发电商合作博弈策略影响下，实现线路准许收入的稳定回收。

Due to the uneven distribution of load centers and renewable resources in geographical locations, the reasonable allocation of resources in a wider range requires cross-regional electricity transmission. With the development of inter-regional electricity transmission and the power market, generators participating in the inter-regional market clearing may exercise market power through cooperative game strategies to maximize their own interests, resulting in the reduction of the utilization rate of inter-regional electricity transmission channels and thus influencing the recovery of lines’ permitted income. In response to the above problems, this paper proposed a tri-level model to optimize inter-regional electricity transmission price considering the cooperative game strategy of inter-regional units in the electricity market environment. The upper layer is a transmission electricity price optimization model with the goal of stable recovery of permitted income. The middle layer is a decision-making model of the report volume with the goal of the maximum revenue of the alliance.The lower layer is the regional power market clearing model with the participation of power generators outside the region. An modified C&CG algorithm was implemented to solve the proposed model, decomposing the model into master and sub-problem to be solved in alternating iterations. The master and sub-problems as the two-layer model were solved by converting Carlo-Kuhn-Tucker condition (KKT) and big M method into equivalent monolayer model, while the bilinear terms in the master and sub-problem models were transformed by strong duality theorem and variable discrete parametric method. Finally, PJM-5 node system demonstrates the proposed tri-level optimization model can better reflect the strategic decision and market power behavior of cross-region clearing interest alliance formed by power generators outside the cooperative game strategy, ensuring the formulation of transmission price can realize the stable recovery of the permitted income of the line under the influence of the cooperative game strategy of power producers outside the region.