Considering the random fluctuation characteristics of active power output of wind farm

the optimization allocation model forof AC-DC parallel transmission channelamong provincial networks in an ACDC interconnected power grid is established.In the model

with the expected minimum total active power lossintheAC-DC transmissionchannelasobjective

the constraints of power exchange plan among provincial networks and DC channels’ power regulation limits areconsidered.The model is a high-dimensional random dynamic programming modelwith very difficult direct solution.The network equivalence method is used to simplify the grid model at each time interval to reduce the number of node numbers in the grid

and the state space approximate dynamic programming algorithm is adopted to achieve the decoupling solution of the optimization model of each time interval.Firstly

the optimization model at output error scenario of each wind farm is solved by way of three-stage method so to obtain the state space and solution.Then

the optimization model at single time interval is solved at one by one time interval under prediction scenario so to obtain ideal solution.The similarity of ideal and state solution is evaluated through such aspects as decision variables

random variablesand objective function values to get approximate optimal solution of each period.With a practical large-scale AC-DC interconnected power grid for as an example

the correctness andeffectivenessoftheproposedmodelandalgorithmareverifiedbythecalculationresult.