Patent ID: 8698330
Filing Date: 2014-04-15
Classification: H02M,H02P

Abstract:
1. A portable inverter power generation apparatus comprising: an engine; an electric generator arranged to generate AC electric power by rotation of the engine; a rectifying circuit arranged to convert the AC electric power generated by the electric generator into DC electric power; an inverter circuit arranged to convert the DC electric power obtained by conversion performed by the rectifying circuit into AC electric power; a current detector arranged to detect an AC output current from the inverter circuit; and a controller arranged and programmed to set a target rotational speed of the engine in response to the AC output current detected by the current detector, and to control a rotational speed of the engine according to the set target rotational speed; wherein in a first case in which the AC output current detected by the current detector increases from a value lower than a first value to a value higher than the first value but lower than a second value, the controller sets the target rotational speed to a value lower than a resonance rotational speed at which the engine resonates until the AC output current detected by the current detector increases to the second value, and the controller sets the target rotational speed to a value higher than the resonance rotational speed when the detected AC output current increases to the second value; in a second case where the AC output current detected by the current detector decreases from a value higher than the second value to a value lower than the second value but higher than the first value, the controller sets the target rotational speed to a value higher than the resonance rotational speed until the AC output current detected by the current detector decreases to the first value, and sets the target rotational speed to a value lower than the resonance rotational speed when the detected AC output current decreases to the first value; the value higher than the first value but lower than the second value in the first case and the value lower than the second value but higher than the first value in the second case refer to any value between the first value and the second value; the value lower than the resonance rotational speed in the first case and the value lower than the resonance rotational speed in the second case refer to any value within a range of values lower than the resonance rotational speed; and the value higher than the resonance rotational speed in the first case and the value higher than the resonance rotational speed in the second case refer to any value within a range of values higher than the resonance rotational speed.