For the uncertainty of wind power and load on power system operation

a calculating method of multi-scenario probabilistic power flow based on piecewise wind power and Gaussian mixture model of load power is proposed. The output power of the wind farms is segmented using the directional power characteristic curves

and the wind power multi-scenario is set up. At the same time

the Gaussian mixture models are developed to set up the load power multi-scenario. Then

the multi-scenario of power injection and the corresponding probability are confirmed. In each scenario

the output power of each wind farm is constant

and the load power obeys Gaussian distribution. Finally

on the basis of the total probability theory

the probabilistic power flow results can be got by integrating probability distribution of the state variables and corresponding weight in each scenario. The modified IEEE 57 system is used to test the proposed method. The simulation results show that the probabilistic power flow calculation process is simplified greatly and the calculation efficiency is improved. This work is supported by National Natural Science Foundation of China(No. 51477174)and State Grid Corporation of China(No. DZB51201503568).