Independent generation and transmission planning methods are already unable to meet the requirement of development of power systems. From the perspective of coordination of generation and transmission expansion planning(G&TEP)

a novel G&TEP model is proposed with N-1 security constraints in consideration of security problems caused by intermittency and randomness of wind power. In order to balance the contradiction between system security and economy

the safety cost is characterized by load shedding. The objective function consists of investment

fuel cost

safety cost and penalty cost of abandoning wind power. A Gaussian mixture model(GMM)

which can provide cluster centers and offer the possibility of the data to the different cluster centers

is introduced to shed the operation scenarios due to the differences in the duration of different load levels and the uncertainties of wind power output. The modified Garver-6 and IEEE-RTS 24 bus systems are used to test the proposed model and methods.