Abstract: A three-phase multilevel inverter is connected to a first direct-current voltage source having a first voltage. Single-phase inverters are each connected in series to a corresponding phase of the three-phase multilevel inverter, and include a second direct-current voltage source, respectively, each having a second voltage. Combined output voltages, which are combinations of boost voltages generated by the three single-phase inverters and output voltages of the three-phase multilevel inverter, are supplied to a load. The control device adjusts a common mode voltage of the combined output voltages to be within a predetermined allowable range, and variation ranges of the line voltages in the combined output voltages to satisfy a specified condition established with the second voltage as a reference.

Abstract: For connected-in-parallel N DC-DC converters (1 to N, where N is 3 or more), a first converter group on which PWM switching is performed with a first carrier, and a second converter group on which PWM switching is performed with a second carrier having a phase different from that of the first carrier, are provided. One or more of the DC-DC converters (1 to N) are assigned to each converter group. A plurality of drive modes in which the number of the DC-DC converters that are driven and the converter groups are set, are provided. The drive modes are switched through comparison between a preset threshold value and a total output of the N DC-DC converters (1 to N), and a ratio between total outputs in the first and second converter groups is set to fall within a predetermined range.

Abstract: A power converter includes an inverter circuit connected between the positive and negative terminals of a DC power supply, three single-phase bridge circuits each connected in series between an AC terminal of one of different phases of the inverter circuit and a motor, and a power conversion controller that generates gate signals to control operations of the inverter circuit and the three single-phase bridge circuits based on phase voltage commands. When a semiconductor switching element of the single-phase bridge circuits fails, the power conversion controller sets the output voltage of the single-phase bridge circuit of a phase to which the faulty semiconductor switching element belongs to zero to continue operation.

Abstract: A motor control device includes: a power source device including a DC-output power conversion device having a first mode for outputting first voltage and a second mode for outputting second voltage higher than the first voltage; a power supply device; and a control device, and controls a motor. When a flying object takes off, the control device controls the power conversion device in the second mode. When the control device judges that flight information which is one or both of information of a motor parameter obtained along with control for the motor and information of an environmental factor relevant to the flight altitude satisfies a predetermined condition, or when the control device has received an operation mode signal for which the first mode is selected on the basis of the flight information during control for the motor, the control device controls the power conversion device in the first mode.

Abstract: A motor control device includes: a step-down device including a DC-output power conversion device having a first mode for outputting first voltage and a second mode for outputting second voltage lower than the first voltage; a power supply device; and a control device, and controls a motor. When a flying object takes off, the control device controls the power conversion device in the first mode. When the control device judges that flight information which is one or both of information of a motor parameter obtained along with control for the motor and information of an environmental factor relevant to the flight altitude of satisfies a predetermined condition, or when the control device has received an mode signal for which the second mode is selected on the basis of the flight information during control for the motor, the control device controls the power conversion device in the second mode.

Abstract: A subtracting unit calculates a voltage deviation of an output voltage of a DC-to-DC converter from a target voltage. A feedback control variable calculator calculates a feedback control variable in each control cycle. In a control cycle in which a crossing of the output voltage and the target voltage is detected by a feedforward control determination unit, a feedforward control variable calculator calculates a feedforward control variable so that a change in the output voltage is prevented. A switching control signal generator generates a control signal for the DC-to-DC converter for controlling the output voltage, according to a summation of the feedforward control variable and the feedback control variable.

Abstract: A power converter includes an inverter circuit connected between the positive and negative terminals of a DC power supply, three single-phase bridge circuits each connected in series between an AC terminal of one of different phases of the inverter circuit and a motor, and a power conversion controller that generates gate signals to control operations of the inverter circuit and the three single-phase bridge circuits based on phase voltage commands. When a semiconductor switching element of the single-phase bridge circuits fails, the power conversion controller sets the output voltage of the single-phase bridge circuit of a phase to which the faulty semiconductor switching element belongs to zero to continue operation.

Abstract: A three-phase multilevel inverter is connected to a first direct-current voltage source having a first voltage. Single-phase inverters are each connected in series to a corresponding phase of the three-phase multilevel inverter, and include a second direct-current voltage source, respectively, each having a second voltage. Combined output voltages, which are combinations of boost voltages generated by the three single-phase inverters and output voltages of the three-phase multilevel inverter, are supplied to a load. The control device adjusts a common mode voltage of the combined output voltages to be within a predetermined allowable range, and variation ranges of the line voltages in the combined output voltages to satisfy a specified condition established with the second voltage as a reference.

Abstract: The power conversion device includes a multilevel boosting circuit and a smoothing capacitor for smoothing output voltage of the multilevel boosting circuit. The multilevel boosting circuit includes: a leg portion in which four semiconductor elements, i.e., a first diode, a second diode, a first switching element, and a second switching element are connected in series; and an intermediate capacitor connected between a connection point of the first diode and the second diode, and a connection point of the first switching element and the second switching element. When voltage of the smoothing capacitor becomes a reference voltage value or more, the control unit executes a protection mode to fix the first switching element and the second switching element in OFF states.

Abstract: The power conversion device includes: a boosting unit for boosting DC voltage, the boosting unit including a second switching element, a third switching element, a second reverse-current blocking element, and a third reverse-current blocking element which are connected in series, the boosting unit including an intermediate capacitor connected between a connection point between the second reverse-current blocking element and the third reverse-current blocking element, and a connection point between the third switching element and the second switching element; a smoothing capacitor which is connected in parallel to the boosting unit and smooths the DC voltage boosted by the boosting unit; and a control unit for turning on the third switching element so that the intermediate capacitor is charged to charge completion voltage of the intermediate capacitor.

Abstract: A laser diode driving power source of a laser machining device that radiates laser light emitted from an LD to a workpiece to machine the workpiece includes a power converter including a switching device, to supply a current to the LD, and a control unit to control a switching operation of the switching device. A value smaller than a value that is n times a time constant for laser machining is set as a switching period of the switching device in the control unit, the n is larger than 1, and the time constant for laser machining is a value obtained by dividing a surface roughness required for machining of the workpiece by a moving velocity of the workpiece.

Abstract: A subtracting unit calculates a voltage deviation of an output voltage of a DC-to-DC converter from a target voltage. A feedback control variable calculator calculates a feedback control variable in each control cycle. In a control cycle in which a crossing of the output voltage and the target voltage is detected by a feedforward control determination unit, a feedforward control variable calculator calculates a feedforward control variable so that a change in the output voltage is prevented. A switching control signal generator generates a control signal for the DC-to-DC converter for controlling the output voltage, according to a summation of the feedforward control variable and the feedback control variable.

Abstract: Provided is an electrostatic capacitance detection device including: an electrode pair including a pair of electrodes, the electrode pair being arranged inside a compressor configured to compress refrigerant; a capacitor being connected in series to the electrode pair; an inverter having one of power lines connected to one end of series-connected electrode pair and capacitor, and is configured to drive the compressor, the power lines being used for driving the compressor; and a voltage detecting unit configured to measure a voltage between the pair of electrodes of the electrode pair.

Abstract: A laser diode driving power source of a laser machining device that radiates laser light emitted from an LD to a workpiece to machine the workpiece includes a power converter including a switching device, to supply a current to the LD, and a control unit to control a switching operation of the switching device. A value smaller than a value that is n times a time constant for laser machining is set as a switching period of the switching device in the control unit, the n is larger than 1, and the time constant for laser machining is a value obtained by dividing a surface roughness required for machining of the workpiece by a moving velocity of the workpiece.

Abstract: The power conversion device includes: a boosting unit for boosting DC voltage, the boosting unit including a second switching element, a third switching element, a second reverse-current blocking element, and a third reverse-current blocking element which are connected in series, the boosting unit including an intermediate capacitor connected between a connection point between the second reverse-current blocking element and the third reverse-current blocking element, and a connection point between the third switching element and the second switching element; a smoothing capacitor which is connected in parallel to the boosting unit and smooths the DC voltage boosted by the boosting unit; and a control unit for turning on the third switching element so that the intermediate capacitor is charged to charge completion voltage of the intermediate capacitor.

Abstract: The power conversion device includes a multilevel boosting circuit and a smoothing capacitor for smoothing output voltage of the multilevel boosting circuit. The multilevel boosting circuit includes: a leg portion in which four semiconductor elements, i.e., a first diode, a second diode, a first switching element, and a second switching element are connected in series; and an intermediate capacitor connected between a connection point of the first diode and the second diode, and a connection point of the first switching element and the second switching element. When voltage of the smoothing capacitor becomes a reference voltage value or more, the control unit executes a protection mode to fix the first switching element and the second switching element in OFF states.

Abstract: A converter supplies an output voltage, generated by stepping down or up an input voltage from a DC power supply, to an inverter for driving an AC motor. In the converter in a boost mode, a buck circuit is stopped, a boost circuit is operated, and a first bypass switch is turned on to form a path from the DC power supply to the boost circuit. In a buck mode, the boost circuit (30) is stopped, the buck circuit is operated, and a second bypass switch is turned on to form a path from the buck circuit to the inverter.

Abstract: A series connection body wherein a first backflow prevention elements, a second backflow prevention element, a first switching element and a second switching element are connected in series in this order; a reactor; a first output capacitor connected between a first end of the series connection body and a second end of the series connection body; and a second output capacitor connected between a connection point between the first switching element and the second switching element and a connection point between the first backflow prevention element and the second backflow prevention element are provided, a DC is inputted between an end of the reactor and the second end section of the series connection body, and power is supplied to a first load connected to both ends of the first output capacitor and a second load connected to both ends of the second output capacitor.

Abstract: A converter supplies an output voltage, generated by stepping down or up an input voltage from a DC power supply, to an inverter for driving an AC motor. In the converter in a boost mode, a buck circuit is stopped, a boost circuit is operated, and a first bypass switch is turned on to form a path from the DC power supply to the boost circuit. In a buck mode, the boost circuit (30) is stopped, the buck circuit is operated, and a second bypass switch is turned on to form a path from the buck circuit to the inverter.

Abstract: In the touch panel device, when a slide operation in an oblique direction by a user is performed, out of a content displayed on the display screen 11 at that time, a region surrounded by an imaginary rectangle in which a start point Pa and an end point Pb of the slide operation are opposing corners and either one side of the imaginary rectangle is parallel to either one side of the display screen is displayed in an enlarged manner so as to fill the entirety of the predetermined region 12 of the display screen 11. With this, an intuitive display enlargement operation can be performed even for a touch panel device not supporting a multi-touch operation.