Abstract: With the increasing scale of wind power installation and grid connection，the interconnection of

power grids through tie lines can absorb wind power in a wider range，but the uncertainty of wind power output leads to an increase in the risk of system operation. Conditional value-at-risk（CVaR）was introduced in multi-regional unit commitment to quantify the risk，and a multi-regional unit commitment model considering conditional value at risk was proposed，so as to balance the operation economy and risk loss of multi-regional unit commitment with an interconnected power grid. Besides，the tie line operation mode was modeled in detail to coordinate the economy and flexibility of tie line operation. By introducing auxiliary variables，the tie line operation mode model was transformed into a mixed-integer linear constraint. Finally，the proposed multi-region unit commitment model was transformed into a mixed-integer linear programming form for the solution. With the improved two area system as a simulation example，the results demonstrate that this method can effectively control the tail risk of the system and improve the ability to resist the wind power output uncertainty while ensuring the operation economy of multi-area internet power grid.

      Key words: interconnection of power grids；conditional value at risk（CVaR）；multi-regional unit commitment；tie lines；uncertainty