NOVELTY - The method involves acquiring active power output and charge state of storage battery by data acquiring device. The acquired data is analyzed. Direct current (DC) in current transformer is controlled. Three-phase voltage and current are converted into components of voltage (Ud,Uq) and active current (Id), reactive current (Iq) of shafts when storage battery is running. The reference value of active current is taken when storage battery is charged. The active and reactive currents are controlled to acquire pulse width modulated (PWM) switch signal.    USE - Method for controlling charging/discharging of storage battery for smoothing fluctuant output power of wind power system.    ADVANTAGE - The smoothing of the fluctuant output power of wind powder station is performed by detecting the active output by the system and the charge state of the storage battery to estimate the remaining capacity of the battery so as to control the running method of the storage battery. The reactive loss of the current transformer by adopting PWM control technology of three-phase bridge circuit is reduced.    DETAILED DESCRIPTION - The method involves controlling the running of storage battery when power (P) is between Pmin and Pmax, where Pmax and Pmin are upper and lower thresholds of fluctuant of output power of wind power station in power system, respectively. The storage battery runs when charge state (soc) is between the minimal charge state value of the battery and one and stops running when charge state is more than 1 or less than minimal charge state value. The absorbing power of the storage battery is equal to P-Pmax when the active power output by the wind power station is less than Pmin. The breaker is cut off and the trigger pulses of the current transformer are preset when the storage battery ends running.    DESCRIPTION OF DRAWING(S) - The drawing shows a flow diagram explaining the method for controlling charging/discharging of storage battery. (Drawing includes non-English language text)    Active current (Id)    Reactive current (Iq)    Voltage of shaft (Ud,Uq)