It is necessary for each control center in interconnected grids to coordinate its voltage/reactive power control to achieve more reasonable reactive power distribution and avoid control oscillating. Based on the network equations

the optimal nodal reactive power injections for L index and active power losses are introduced respectively. A coordinated voltage/reactive power control model based distributed computation is proposed. The model can be used to optimize L index and active power losses. Simulations on interconnected grids verify that the proposed method is sound and effective.