The initial values of wind power units are the basis of steady-state dispatch and transient analysis for wind power systems.Constant koptmodel is often applied for initialization of doubly-fed induction generators（DFIGs）in the maximum power point tracking strategy.However，the resultant speeds of the induction generator and the wind turbine are contradictory，and this model is unsuitable for spinning reserve.For initial values of DFIGs with spinning reserve，two initialization methods，i.e.speed constraint and power constraint，are proposed.The former method sets the rotor speed constant（not necessarily the optimal speed），with the known captured power，the active output of wind power unit and the voltages of the rotor and the converters are solved simultaneously with network power flow equations.The latter sets the power output as known variable，the voltages of the rotor and the converters，the slip（or the pitch angle）and the captured power are solved independently with network power flow equations.Both methods have different numbers of constraints and variables，but yield consistent rotor speed and are suitable for spinning reserve dispatch regardless of wind speed.The example results validate the feasibility and accuracy of the proposed methods.