To smoothly operate the starting rotation of a wind power generator from low wind velocity, to control the current-carrying ratio so that the wind power generator can be laid in a load state capable of taking a maximum output without stalling, and to increase the output current of the wind power generator to charge a storage battery.

The wind power generator is connected to a voltage adjustor for keeping secondary voltage constant even in the fluctuation of primary voltage through a connection part for connecting and controlling the output from the wind power generator. The charging current to the storage battery is controlled by the output voltage of the wind power generator. The charging output to the storage battery is outputted from a current-carrying rate adjuster.