Abstract: In an electronic device, a stay is fixed to a surface of a heatsink on the side of a substrate or to a side surface of the heatsink, and is also fixed to the substrate. A contact portion of the stay which is in contact with the heatsink is in contact with the heatsink by mating therewith. The electron device is further provided with a fastening member for fixing the contact potion to the heatsink in detachable manner.

Abstract: A power conversion apparatus includes: a converter that includes input terminals and switching elements corresponding to respective phases of a three-phase AC power supply and converts an AC voltage of the three-phase AC power supply into a DC voltage, and a capacitor that smooths the DC voltage converted by the converter. A single-phase AC power supply or a DC power supply is connected to two of the input terminals corresponding to any two of the three phases of the converter while a passive element is provided to connect the remaining one of the input terminals corresponding to the phase to which the single-phase AC power supply or the DC power supply is not connected, with one terminal of the capacitor.

Abstract: A power conversion apparatus includes: a converter that includes input terminals and switching elements corresponding to respective phases of a three-phase AC power supply and converts an AC voltage of the three-phase AC power supply into a DC voltage, and a capacitor that smooths the DC voltage converted by the converter. A single-phase AC power supply or a DC power supply is connected to two of the input terminals corresponding to any two of the three phases of the converter while a passive element is provided to connect the remaining one of the input terminals corresponding to the phase to which the single-phase AC power supply or the DC power supply is not connected, with one terminal of the capacitor.

Abstract: A motor drive apparatus includes an AC stabilized power supply configured to convert AC voltage of a commercial AC power source into input power supply voltage according to a received voltage command value and output the input power supply voltage, a converter configured to convert the input power supply voltage into DC voltage and output the DC voltage to a DC link, an inverter configured to convert the DC voltage at the DC link into AC voltage for driving a motor, and an input power supply voltage control unit configured to control the input power supply voltage that is output by the AC stabilized power supply.

Abstract: A motor drive device includes a power conversion unit configured to selectively execute a converter operation of converting AC power into DC power, and an inverter operation of converting DC power into AC power for motor driving, a power storage unit configured to store DC power output from the power conversion unit and also supply DC power to the power conversion unit, a switching unit configured to switch between an AC power supply and a motor a connection destination of the power conversion unit, and a control unit configured to control the switching unit to have the power conversion unit connected to the AC power supply and control the power conversion unit to have the converter operation executed, and configured to control the switching unit to have the power conversion unit connected to the motor and control the power conversion unit to have the inverter operation executed.

Abstract: A motor drive device includes a PWM converter configured to convert AC power supplied from an AC power supply into DC power and supply it to a DC link, a DC link capacitor which is provided in the DC link and may store the DC power, an inverter configured to convert the DC power in the DC link into AC power for motor driving and output it, and a boosting ratio control unit configured to control the boosting ratio as the ratio of the value of the DC voltage output from the PWM converter to the peak value of the AC voltage input from the AC power supply, to allow a motor to be driven using AC power output by converting the DC power stored in the DC link capacitor by the inverter during shut-off of supply of the DC power from the PWM converter to the DC link.

Abstract: A motor drive apparatus includes an AC stabilized power supply configured to convert AC voltage of a commercial AC power source into input power supply voltage according to a received voltage command value and output the input power supply voltage, a converter configured to convert the input power supply voltage into DC voltage and output the DC voltage to a DC link, an inverter configured to convert the DC voltage at the DC link into AC voltage for driving a motor, and an input power supply voltage control unit configured to control the input power supply voltage that is output by the AC stabilized power supply.

Abstract: A motor drive device includes a power conversion unit configured to selectively execute a converter operation of converting AC power into DC power, and an inverter operation of converting DC power into AC power for motor driving, a power storage unit configured to store DC power output from the power conversion unit and also supply DC power to the power conversion unit, a switching unit configured to switch between an AC power supply and a motor a connection destination of the power conversion unit, and a control unit configured to control the switching unit to have the power conversion unit connected to the AC power supply and control the power conversion unit to have the converter operation executed, and configured to control the switching unit to have the power conversion unit connected to the motor and control the power conversion unit to have the inverter operation executed.

Abstract: A motor driving apparatus includes an AC-DC conversion unit that converts AC power into DC power, a power storage unit provided in a DC link between the AC-DC conversion unit and a DC-AC conversion unit, an initial charging unit that is provided in the DC link, includes a switch unit and a charging resistor connected to the switch unit in parallel, and initially charges the power storage unit, an electromagnetic contactor that opens and closes an electrical path between the AC power source and the AC-DC conversion unit, and a control unit, and after completion of driving of a motor, the control unit performs an opening operation on the electromagnetic contactor and the switch unit and performs a turn-on operation on each of the switching devices provided on the upper and lower arms in the same phase to discharge charge stored in the power storage unit by the charging resistor.

Abstract: A motor drive device includes a PWM converter configured to convert AC power supplied from an AC power supply into DC power and supply it to a DC link, a DC link capacitor which is provided in the DC link and may store the DC power, an inverter configured to convert the DC power in the DC link into AC power for motor driving and output it, and a boosting ratio control unit configured to control the boosting ratio as the ratio of the value of the DC voltage output from the PWM converter to the peak value of the AC voltage input from the AC power supply, to allow a motor to be driven using AC power output by converting the DC power stored in the DC link capacitor by the inverter during shut-off of supply of the DC power from the PWM converter to the DC link.

Abstract: A machine learning apparatus includes a state observation unit which observes a state variable including at least one of data associated with the value of a DC voltage in a DC link, data associated with the amount of power supply regeneration representing the amount of power returned from the DC link to an AC power supply by a power supply regeneration operation by a converter, and data associated with the occurrence or nonoccurrence of an overvoltage alarm indicating that the DC voltage of the DC link has exceeded a preset overvoltage alarm level, and a learning unit learns conditions associated with the power supply regeneration operation by the converter, in accordance with a training data set defined by the state variable.

Abstract: A motor driving device includes, a PWM converter that performs power conversion between AC power and DC power in a DC link, an inverter that converts the DC power in the DC link to AC power for a motor and that converts the AC power from the motor to DC power for returning to the DC link, a power storage unit that stores the DC power, a switch that connects or disconnects between an AC power supply and the PWM converter in response to a command, and a command unit that continues outputting a connection command to the switch while a DC voltage in the DC link is boosted up to a prescribed voltage by the DC power, and that initiates outputting a disconnection command to the switch after the DC voltage in the DC link reaches the prescribed voltage and before the inverter initiates powering operation.

Abstract: A motor driving apparatus includes an AC-DC conversion unit that converts AC power into DC power, a power storage unit provided in a DC link between the AC-DC conversion unit and a DC-AC conversion unit, an initial charging unit that is provided in the DC link, includes a switch unit and a charging resistor connected to the switch unit in parallel, and initially charges the power storage unit, an electromagnetic contactor that opens and closes an electrical path between the AC power source and the AC-DC conversion unit, and a control unit, and after completion of driving of a motor, the control unit performs an opening operation on the electromagnetic contactor and the switch unit and performs a turn-on operation on each of the switching devices provided on the upper and lower arms in the same phase to discharge charge stored in the power storage unit by the charging resistor.

Abstract: A motor drive includes an electromagnetic connector for connecting an alternating current (AC) power source to an AC/DC conversion unit or disconnecting therefrom, a DC link unit, a DC/AC conversion unit for converting smoothed direct current voltage to AC voltage, a DC link voltage detection unit for measuring voltage of the DC link unit, and a control unit. The control unit includes a time measurement unit for measuring elapsed time since switching by the electromagnetic connector, and a welding judgment unit for judging that the electromagnetic connector is welded, provided that the difference between voltage between terminals of the DC link unit after charging the DC link unit and voltage between the terminals of the DC link unit after predetermined time has elapsed since disconnecting the AC power source from the AC/DC conversion unit, after the charge of the DC link unit, is less than a predetermined voltage level.

Abstract: A machine learning apparatus includes a state observation unit which observes a state variable including at least one of data associated with the value of a DC voltage in a DC link, data associated with the amount of power supply regeneration representing the amount of power returned from the DC link to an AC power supply by a power supply regeneration operation by a converter, and data associated with the occurrence or nonoccurrence of an overvoltage alarm indicating that the DC voltage of the DC link has exceeded a preset overvoltage alarm level, and a learning unit learns conditions associated with the power supply regeneration operation by the converter, in accordance with a training data set defined by the state variable.

Abstract: An electric motor drive apparatus includes: an AC/DC converter converting AC into DC by the switching of multiple power devices; a control circuit performing PWM switching control of the multiple power devices; a current detecting circuit that detects input current from the AC power supply to the AC/DC converter; an electromagnetic contactor connecting or cutting off power from the AC power supply to the AC converter; and a DC link unit including a smoothing capacitor for smoothing DC voltage, and is constructed such that the control circuit determines that the electromagnetic contactor has been welded when input current is detected in a condition where with the DC link unit having been charged, the electromagnetic contactor is turned off to cut off the power from the AC power supply to the AC/DC converter and the multiple power devices are controlled by PWM switching in accordance with the switching commands.

Abstract: A motor driving device includes, a PWM converter that performs power conversion between AC power and DC power in a DC link, an inverter that converts the DC power in the DC link to AC power for a motor and that converts the AC power from the motor to DC power for returning to the DC link, a power storage unit that stores the DC power, a switch that connects or disconnects between an AC power supply and the PWM converter in response to a command, and a command unit that continues outputting a connection command to the switch while a DC voltage in the DC link is boosted up to a prescribed voltage by the DC power, and that initiates outputting a disconnection command to the switch after the DC voltage in the DC link reaches the prescribed voltage and before the inverter initiates powering operation.

Abstract: A motor drive device driven by a three-phase AC, which drives a motor by an AC/DC converter and DC/AC converter controlled by a controller, and which has an electromagnetic contractor without an auxiliary contact in an input power circuit, which motor control device is provided at the controller with an off circuit of the electromagnetic contactor and a partial controller of the three-phase bridge circuit at the AC/DC converter, turns on an upper arm of a predetermined phase of the three-phase bridge circuit and turns on the lower arms of other phases in the state where the electromagnetic contactor is turned off, judges the presence of current in this state by the current detector, and, when the current detector detects current, uses a contact fusion detector to detecte contact fusion in the electromagnetic contactor and thereby can detect fusion of a contact in the electromagnetic contactor without an additional circuit.

Abstract: An electric motor drive apparatus includes: an AC/DC converter converting AC into DC by the switching of multiple power devices; a control circuit performing PWM switching control of the multiple power devices; a current detecting circuit that detects input current from the AC power supply to the AC/DC converter; an electromagnetic contactor connecting or cutting off power from the AC power supply to the AC converter; and a DC link unit including a smoothing capacitor for smoothing DC voltage, and is constructed such that the control circuit determines that the electromagnetic contactor has been welded when input current is detected in a condition where with the DC link unit having been charged, the electromagnetic contactor is turned off to cut off the power from the AC power supply to the AC/DC converter and the multiple power devices are controlled by PWM switching in accordance with the switching commands.

Abstract: A motor drive includes an electromagnetic connector for connecting an alternating current (AC) power source to an AC/DC conversion unit or disconnecting therefrom, a DC link unit, a DC/AC conversion unit for converting smoothed direct current voltage to AC voltage, a DC link voltage detection unit for measuring voltage of the DC link unit, and a control unit. The control unit includes a time measurement unit for measuring elapsed time since switching by the electromagnetic connector, and a welding judgment unit for judging that the electromagnetic connector is welded, provided that the difference between voltage between terminals of the DC link unit after charging the DC link unit and voltage between the terminals of the DC link unit after predetermined time has elapsed since disconnecting the AC power source from the AC/DC conversion unit, after the charge of the DC link unit, is less than a predetermined voltage level.