Abstract: The invention relates to a control unit of an electric power conversion apparatus that can decrease the high-order harmonic content generated by resonance of the inductance component of the primary wiring connecting an AC power supply 20 and the electric power conversion apparatus and a capacitor connected as a filter even if distortion occurs in an input current waveform.

Abstract: The invention relates to a control unit of an electric power conversion apparatus that can decrease the high-order harmonic content generated by resonance of the inductance component of the primary wiring connecting an AC-power supply 20 and the electric power conversion apparatus and a capacitor connected as a filter even if distortion occurs in an input current waveform.

Abstract: A power converter which can provide a power supply grounded on a positive electrode bus of a DC power supply without adding an additional power supply such as a switching regulator and reduce a circuit size and cost is described. When a switching device T1 of an upper arm is ON, the potential at point U is nearly equal to the potential at point P, and the current ic1 flows from the positive electrode of a first drive power supply 21 into a capacitor C1 via a diode D7 to charge the capacitor C1. A power supply Vc formed by the capacitor C1 can be used as a power supply grounded on a positive electrode bus P of the DC power supply.

Abstract: A power converting apparatus is obtained in which an integrated circuit for driving a power switching element is operated under stable conditions. A core 100 functioning as a common mode transformer made of a material such as ferrite is connected to a wiring line connected between a switch 7, a switch 8, and an IC 13 for opening/closing these switches 7 and 8 in a complementary manner, so that an impedance of a current path to the switch 7 and the IC 13 is increased.

Abstract: A power converting apparatus is comprised of an inverter unit arranged by a switching semiconductor element 51a for an upper arm and another switching semiconductor element 51d for a lower arm, and for turning ON/OFF the switching semiconductor elements to thereby convert DC power inputted from a DC power supply into AC power; and control means 10a for judging as to whether or not an abnormal operation is present based upon an output of a comparator 11a for judging as to whether or not a detection voltage detected by a voltage detecting circuit 61 is substantially equal to a voltage of the positive polarity; an output of a comparator 11b for judging as to whether or not a detection voltage detected by the voltage detecting circuit 61 is substantially equal to a voltage of the negative polarity; and an output signal of an igniting signal for ON/OFF-controlling the switching semiconductor elements, this voltage detecting circuit 61 detecting an output voltage of the inverter unit via a voltage dividing resistor

Abstract: A power conversion apparatus and its control method is disclosed in which a main circuit and its control circuit are simplified by allowing part of the main circuit to be shared by a converter section and an inverter section. The power conversion apparatus comprises a converter section 120 and an inverter section 130, each having upper and lower arm switch sections, and a common section 110 also having upper and lower arm switch sections. One phase of an AC input power terminal is connected to one phase of an AC output power terminal. The common phase is also connected to a connection point 1RU of the upper and lower arm switch sections of the common section. The remaining phases of the AC input terminals are connected to connecting points of upper and lower arm switch sections of the converter section, and the remaining phases of the AC output terminals are connected to connection points of upper and lower arm switch sections of the inverter section.

Abstract: A flywheel type energy storage apparatus for use in an uninterruptible power supply has an induction motor which serves as a generator/motor, in which a rotor (65) of the induction motor is constituted by incorporation of a rotor core (62) and a flywheel (64) with a rotor shaft (56) vertically born by a pivot bearing (55) and a magnetic bearing (67).

Abstract: A supply for an AC (alternating current) output having a constant voltage and a constant frequency to a load such as computers. A constant voltage/frequency power supply apparatus is provided which includes at least a constant voltage/frequency output circuit including a converter, connected between an AC power source and the load, for DC-converting the AC output of this power source, and an inverter for AC-inverting the DC-converted output, a control circuit for controlling the inverter of the output circuit, and further a correction circuit for deleting as a DC magnetic polarization amount a DC component contained in the AC output of the output circuit, and for deleting a DC magnetic polarization amount from the AC output supplied to the load, based upon the detected DC magnetic polarization amount, whereby a sine wave AC output having a constant voltage/frequency which is not adversely influenced by the DC magnetic polarization is supplied to the load.

Abstract: The present invention is directed to supply an AC (alternating current) output having a constant voltage and a constant frequency to a load such as computers. A constant voltage/frequency power supply apparatus is provided which comprises at least a constant voltage/frequency output circuit including a converter, connected between an AC power source and the load, for DC-converting the AC output of this power source, and an inverter for AC-inverting the DC-converted output, a control circuit for controlling the inverter of the output circuit, and further a correction means for deleting as a DC magnetic polarization amount a DC component contained in the AC output of the output circuit, and for deleting a DC magnetic polarization amount from the AC output supplied to the load, based upon the detected DC magnetic polarization amount, whereby a sine wave AC output having a constant voltage/frequency which is not adversely influenced by the DC magnetic polarization is supplied to the load.