The study of power flow calculation method after integration of wind power is helpful in determining integration scheme of wind farm and in providing foundation for the further study in such aspects as system stability and reliability etc. Based on the traditional RX model of asynchronous wind power unit

reactive power of the wind power unit is expressed as the function of voltage so to eliminate the influence of rotation tolerance and to avoid the two iteration process in the conventional RX model algorithm and retain the quadratic convergence speed of Newton iteration method. The power flow calculation model of wind farm integration is defined with combination of existed power flow calculation and the influence of different wind farm model on the system flow is calculated and analyzed.