Patent ID: 8227935

Claim:
A hybrid power supply device comprising an engine generator and a capacitor, wherein that the device comprises: a DC bus having the engine generator and the capacitor connected in parallel and supplying electric power to an outside; a step-up converter provided between the DC bus and the engine generator and controlling a current amount supplied from the engine generator to the DC bus; a step-up/down converter provided between the DC bus and the capacitor and controlling a voltage of the DC bus so as to be maintained at a predetermined set voltage; and a control section controlling an operation of the step-up/down converter and the step-up converter, and the control section controls the step-up converter so as to supply a part of a current amount supplied to the outside from the engine generator to the DC bus and controls the step-up/down converter so as to maintain the voltage of the DC bus at the predetermined set voltage higher than an output voltage of the engine generator, wherein the engine generator has a supercharging mechanism, and wherein the control section controls an increase rate of a current amount supplied from the engine generator to the voltage of the DC bus so that an increase rate of a current amount after exceeding a maximum current amount obtained at the time of a non-supercharging maximum power output in which the supercharging mechanism is not used in the engine generator is smaller than an increase rate of a current amount up to the maximum current amount obtained at the time of the non-supercharging maximum power output when the current amount supplied to the outside increases.