Abstract: A full-bridge inverter is configured with a parallel connection of a first leg and a second leg, and controlled in a dual-leg resonant mode in which a positive-side switching element of the first leg and a negative-side switching element of the second leg are turned on/off at the same time and a negative-side switching element of the first leg and a positive-side switching element of the second leg are turned on/off at the same time, and controlled in a single-leg resonant mode in which the positive-side switching element of the first leg and the negative-side switching element of the second leg, and the negative-side switching element of the first leg and the positive-side switching element of the second leg are turned on/off shiftedly in time by a phase shift amount.

Abstract: An electric motor drive device includes a smoothing capacitor and an inverter, and further includes an overvoltage protection unit for overvoltage protection for the smoothing capacitor, and a phase short-circuit control unit. The overvoltage protection unit includes: a discharge circuit having a discharge resistor and an IGBT connected in series; and a first determination circuit which determines, with determination delay, that smoothing capacitor voltage exceeds first set voltage, and turns on the IGBT. The phase short-circuit control unit is provided in a control device for drive-controlling the inverter and includes a second determination circuit which determines, with a determination period longer than the determination delay of the first determination circuit, that smoothing capacitor voltage exceeds second set voltage lower than the first set voltage, to perform phase short-circuit control for the inverter.

Abstract: During regenerative control of an inverter circuit, when a path between a DC power supply and a smoothing capacitor is in a disconnection state, a control circuit of a power conversion device performs control while switching between first control in which upper switching elements within the inverter circuit are turned on and all lower switching elements are turned off and second control in which the lower switching elements are turned on and all the upper switching elements are turned off, every predetermined switching period.

Abstract: A rotating electric machine with a built-in control device that can be downsized. The rotating electric machine with a built-in control device includes a rotor including a permanent magnet of sensor use provided on a rear side of a rotor shaft, a front side housing fixed with a first bearing supporting a front side of the rotor shaft, a motor frame including a rotor and a stator, a heat sink fixed with a second bearing supporting the rear side of the rotor shaft, a control substrate mounting a rotary sensor, a microcomputer, and a driving circuit. The microcomputer controls the driving circuit based on signals from the rotary sensor and drives a plurality of switching elements. At least one of a smoothing condenser and a noise reduction coil, connected to the switching elements, is arranged at a far rear side of the control substrate.

Abstract: A motor drive control device for electric power steering includes: a switching element for supplying current to a motor; a smoothing capacitor for reducing ripple current due to the switching element; a control board on which a drive circuit for controlling the switching element and a control circuit capacitor are mounted; a control signal line for supplying a control signal from the control board to the switching element; an electric connection member electrically connecting the switching element and the smoothing capacitor; and a heatsink portion in which the switching element is arranged in an embedded manner, wherein the electric connection member is arranged between the switching element and the control board, and the control circuit capacitor and the smoothing capacitor are arranged in a space between the electric connection member and the control board.

Abstract: During regenerative control of an inverter circuit, when a path between a DC power supply and a smoothing capacitor is in a disconnection state, a control circuit of a power conversion device performs control while switching between first control in which upper switching elements within the inverter circuit are turned on and all lower switching elements are turned off and second control in which the lower switching elements are turned on and all the upper switching elements are turned off, every predetermined switching period.

Abstract: A diode rectifier rectifies an AC voltage output from a neutral-grounding three-phase AC power supply to a DC voltage. A smoothing capacitor smoothes the DC voltage rectified by the diode rectifier. An inverter converts the DC voltage smoothed by the smoothing capacitor into a desired AC voltage. A bidirectional switch and a Y capacitor are connected in series between one end of the smoothing capacitor and the ground. A detector detects a voltage across both ends of the smoothing capacitor. A controller drives the bidirectional switch in response to an output of the detector.

Abstract: A motor drive control device for electric power steering includes: a switching element for supplying current to a motor; a smoothing capacitor for reducing ripple current due to the switching element; a control board on which a drive circuit for controlling the switching element and a control circuit capacitor are mounted; a control signal line for supplying a control signal from the control board to the switching element; an electric connection member electrically connecting the switching element and the smoothing capacitor; and a heatsink portion in which the switching element is arranged in an embedded manner, wherein the electric connection member is arranged between the switching element and the control board, and the control circuit capacitor and the smoothing capacitor are arranged in a space between the electric connection member and the control board.

Abstract: A semiconductor switch circuit includes a plurality of switching units connected in series between a high-voltage node and a low-voltage node, and a plurality of diodes provided in association with the plurality of switching units, respectively. Respective cathodes of the plurality of diodes are connected to the plurality of switching units, respectively, and the anode of the diode associated with the switching unit connected to the low-voltage node receives a predetermined power supply voltage. Each switching unit includes a semiconductor switching device, a gate drive circuit driving the semiconductor switching device, and a DC-DC converter receiving a DC voltage from a cathode of the associated diode and supplying drive power to the gate drive circuit.

Abstract: A gate-power-supply device is provided with an inverter circuit, a transformer, and rectifier circuits. The device includes secondary-side parallel capacitors, connected in parallel to secondary-side coils of the transformer, for cancelling inductance components of the secondary-side coils at the drive frequency of the inverter circuit. The device includes a primary-side series capacitor, connected in series to a primary-side coil of the transformer, for cancelling the imaginary term (inductance component) of the combined impedance of the gate drivers, the rectifier circuits, the secondary-side parallel capacitors, the secondary-side coils, transformer cores and the primary-side coil, which are a load viewed from the inverter circuit.

Abstract: A rotating electric machine with a built-in control device that can be downsized. The rotating electric machine with a built-in control device includes a rotor including a permanent magnet of sensor use provided on a rear side of a rotor shaft, a front side housing fixed with a first bearing supporting a front side of the rotor shaft, a motor frame including a rotor and a stator, a heat sink fixed with a second bearing supporting the rear side of the rotor shaft, a control substrate mounting a rotary sensor, a microcomputer, and a driving circuit. The microcomputer controls the driving circuit based on signals from the rotary sensor and drives a plurality of switching elements. At least one of a smoothing condenser and a noise reduction coil, connected to the switching elements, is arranged at a far rear side of the control substrate.

Abstract: A semiconductor switch circuit includes a plurality of switching units connected in series between a high-voltage node and a low-voltage node, and a plurality of diodes provided in association with the plurality of switching units, respectively. Respective cathodes of the plurality of diodes are connected to the plurality of switching units, respectively, and the anode of the diode associated with the switching unit connected to the low-voltage node receives a predetermined power supply voltage. Each switching unit includes a semiconductor switching device, a gate drive circuit driving the semiconductor switching device, and a DC-DC converter receiving a DC voltage from a cathode of the associated diode and supplying drive power to the gate drive circuit.

Abstract: A gate-power-supply device is provided with an inverter circuit, a transformer, and rectifier circuits. The device includes secondary-side parallel capacitors, connected in parallel to secondary-side coils of the transformer, for cancelling inductance components of the secondary-side coils at the drive frequency of the inverter circuit. The device includes a primary-side series capacitor, connected in series to a primary-side coil of the transformer, for cancelling the imaginary term (inductance component) of the combined impedance of the gate drivers, the rectifier circuits, the secondary-side parallel capacitors, the secondary-side coils, transformer cores and the primary-side coil, which are a load viewed from the inverter circuit.

Abstract: A three-phase rectification circuit rectifies output voltage of a three-phase AC power supply, a step-up converter circuit steps up the output voltage, and a smoothing device smoothes the stepped-up output voltage. A voltage detection circuit detects output voltage VoL of the smoothing device, and an AC current component detection circuit extracts AC component included in output current of the three-phase rectification circuit and outputs a detection signal ViL corresponding to the AC component. A control circuit calculates a deviation ?Vdc1 (=Vs?VoL?ViL) among an output voltage instruction Vs for output voltage of the step-up converter circuit and detection signals VoL and ViL obtained by the detection circuits, and generates a pulse signal for suppressing the deviation ?Vdc1 to zero, thereby performing PWM control for a switching device of the step-up converter circuit.

Abstract: A three-phase rectification circuit rectifies output voltage of a three-phase AC power supply, a step-up converter circuit steps up the output voltage, and a smoothing device smoothes the stepped-up output voltage. A voltage detection circuit detects output voltage VoL of the smoothing device, and an AC current component detection circuit extracts AC component included in output current of the three-phase rectification circuit and outputs a detection signal ViL corresponding to the AC component. A control circuit calculates a deviation ?Vdc1 (=Vs?VoL?ViL) among an output voltage instruction Vs for output voltage of the step-up converter circuit and detection signals VoL and ViL obtained by the detection circuits, and generates a pulse signal for suppressing the deviation ?Vdc1 to zero, thereby performing PWM control for a switching device of the step-up converter circuit.

Abstract: The present invention provides a power device including a converter part (2) for converting an AC voltage to a DC voltage; an inverter part (3) for converting the DC voltage outputted from the converter part (2) to the AC voltage; and a transformer (4) having an inductance forming a series resonance circuit together with an electrostatic capacity of a load (20) to boost the AC voltage outputted from the inverter part (3). In the power device, an inductance (7) is connected to the output part of the inverter part (3) in parallel with the transformer (4). Thus, in a discharge part 6 provided in the load (20), since when a discharge is not generated, a recovery current is not supplied to a circulating current diode in the inverter part (3), or the quantity of the recovery current is reduced, the heat generation of the circulating current diode can be suppressed without increasing the number of elements of the circulating current diode.

Abstract: The present invention provides a power device including a converter part (2) for converting an AC voltage to a DC voltage; an inverter part (3) for converting the DC voltage outputted from the converter part (2) to the AC voltage; and a transformer (4) having an inductance forming a series resonance circuit together with an electrostatic capacity of a load (20) to boost the AC voltage outputted from the inverter part (3). In the power device, an inductance (7) is connected to the output part of the inverter part (3) in parallel with the transformer (4). Thus, in a discharge part 6 provided in the load (20), since when a discharge is not generated, a recovery current is not supplied to a circulating current diode in the inverter part (3), or the quantity of the recovery current is reduced, the heat generation of the circulating current diode can be suppressed without increasing the number of elements of the circulating current diode.

Abstract: A redundancy circuit for a diode circuit composed of a plurality of diodes connected in series, according to the present invention, includes: bypass circuits, each of which is connected in parallel to each group, the diode circuit being divided into a plurality of group, each group having one or more diodes connected in series, and each bypass circuit including a first voltage-controlled switching device connected in parallel to the corresponding group, and a detection circuit which has a constant voltage device and a fusing circuit, both of which are connected in series, the detection circuit being connected in parallel to the corresponding group; and when, because of increased resistance of any diode, a voltage applied to one of the groups exceeds a given voltage defined by the constant voltage device, the voltage-controlled switching device is turned on so as to bypass a current that is to pass through the corresponding group, whereby continuing the operation of the whole apparatus even when one or more di

Abstract: A redundancy circuit for a diode circuit composed of a plurality of diodes connected in series, according to the present invention, includes: bypass circuits, each of which is connected in parallel to each group, the diode circuit being divided into a plurality of group, each group having one or more diodes connected in series, and each bypass circuit including a first voltage-controlled switching device connected in parallel to the corresponding group, and a detection circuit which has a constant voltage device and a fusing circuit, both of which are connected in series, the detection circuit being connected in parallel to the corresponding group; and when, because of increased resistance of any diode, a voltage applied to one of the groups exceeds a given voltage defined by the constant voltage device, the voltage-controlled switching device is turned on so as to bypass a current that is to pass through the corresponding group, whereby continuing the operation of the whole apparatus even when one or more di