A transmission system planning method considering the uncertainty and probability distribution of wind power is proposed in this paper. The method ensure that the security requirement of system operation be satisfied under various possible probability distribution of wind power

while minimizing the investment costs. Firstly

the robust chanceconstrained optimization model is applied to the transmission system planning problem. Secondly

the Slemma and Schur complement are used to eliminate the random variables

so as to convert the probabilistic model into a deterministic model with matrix inequalities. At last

the genetic algorithm based on the linear matrix inequality optimization is used to solve the deterministic model. Simulations are performed with a real power system to verify the effectiveness of the proposed method.