Abstract: A motor drive apparatus comprises: a converter which converts DC power into AC power and returns the AC power to an AC power supply; a 120-degree conduction regenerative power control unit which controls the converter using a 120-degree conduction method so that the power recovered through the converter is returned to the AC power supply; a PWM regenerative power control unit which controls the converter using a PWM control method so that the power is returned to the AC power supply; an input voltage detection unit which detects a supply voltage supplied to the converter; a DC link voltage detection unit which detects a DC link voltage; and a regenerative method switching unit which, during power regeneration, performs switching between the 120-degree conduction method and the PWM control method in accordance with a given criterion, based on a voltage value detected by the DC link voltage detection unit.

Abstract: A cooling device includes an electrode unit which is arranged in a space between adjacent radiation fins and which is electrically insulated from the radiation fins, and a power supply source which applies a voltage between a heat radiation structure and the electrode unit. The cooling device is further provided with an insulation resistance detection unit which calculates an insulation resistance between the heat radiation structure and the electrode unit, and a comparison unit which compares the insulation resistance calculated by the insulation resistance detection unit with a predetermined threshold, wherein, as a result of the comparison of the calculated insulation resistance and the predetermined threshold by the comparison unit, when the calculated insulation resistance is lower than the predetermined threshold, the cooling device is adapted to judge that the radiation fins have clogged.

Abstract: A cooling device includes an electrode unit which is arranged in a space between adjacent radiation fins and which is electrically insulated from the radiation fins, and a power supply source which applies a voltage between a heat radiation structure and the electrode unit. The cooling device is further provided with an insulation resistance detection unit which calculates an insulation resistance between the heat radiation structure and the electrode unit, and a comparison unit which compares the insulation resistance calculated by the insulation resistance detection unit with a predetermined threshold, wherein, as a result of the comparison of the calculated insulation resistance and the predetermined threshold by the comparison unit, when the calculated insulation resistance is lower than the predetermined threshold, the cooling device is adapted to judge that the radiation fins have clogged.

Abstract: A motor drive apparatus comprises: a converter which converts DC power into AC power and returns the AC power to an AC power supply; a 120-degree conduction regenerative power control unit which controls the converter using a 120-degree conduction method so that the power recovered through the converter is returned to the AC power supply; a PWM regenerative power control unit which controls the converter using a PWM control method so that the power is returned to the AC power supply; an input voltage detection unit which detects a supply voltage supplied to the converter; a DC link voltage detection unit which detects a DC link voltage; and a regenerative method switching unit which, during power regeneration, performs switching between the 120-degree conduction method and the PWM control method in accordance with a given criterion, based on a voltage value detected by the DC link voltage detection unit.

Abstract: A motor driving apparatus having a converter, which receives AC voltage and converts it to DC power, and an inverter, which receives the DC power and converts it to AC power, includes a charge/discharge control circuit and a capacitor connected in parallel to a link section between the converter and the inverter, and energy stored in the capacitor C8 is charged and discharged at arbitrary timing by the charge/discharge control circuit. The invention thus provides a motor driving apparatus that supplies energy to a motor so that the peak of the input current from a power supply to the motor can also be suppressed when particularly large energy is needed during the second half period of motor acceleration.

Abstract: A motor driver for a machine tool, which comprises a fan motor, configured to drive a cooling fan for cooling a radiator or the interior of the motor driver, estimates a rate of heat release within a heating element or the motor driver, based on information obtained from a motor current detector used for motor control or from an input current detector of the motor driver, and adjusts a fan motor power supply voltage to control a rotational speed of the fan motor in accordance with the estimated heat release value.

Abstract: A motor driving apparatus having a converter, which receives AC voltage and converts it to DC power, and an inverter, which receives the DC power and converts it to AC power, includes a charge/discharge control circuit and a capacitor connected in parallel to a link section between the converter and the inverter, and energy stored in the capacitor C8 is charged and discharged at arbitrary timing by the charge/discharge control circuit. The invention thus provides a motor driving apparatus that supplies energy to a motor so that the peak of the input current from a power supply to the motor can also be suppressed when particularly large energy is needed during the second half period of motor acceleration.

Abstract: A motor drive apparatus used for an industrial machine, comprising a converter (4) for converting an AC voltage supplied from an external power source to DC voltage, a capacitor bank (7) connected to the output of the converter (4), and a control apparatus (8) stopping the functions of the capacitor bank when detecting an abnormality of the capacitor bank, whereby the safety of the motor drive apparatus when an abnormality occurs in the capacitor bank is secured by building into the capacitor bank a circuit or function for protecting the capacitor bank and motor drive apparatus and whereby electric shock is prevented even when a person mistakenly touches the capacitor bank when the capacitor bank stores a charge.

Abstract: A motor driving apparatus includes a converter unit that converts alternating-current voltage supplied from an external power source into direct-current voltage, and a motor driving unit that receives direct-current power output from the converter unit and drives a motor. The motor driving apparatus stores direct-current power from the converter unit and regenerated power from the motor, and stores these power in a capacitor bank connected in series to a charging and discharging circuit. The capacitor bank connected in series to the charging and discharging circuit is integrated with a charging and discharging circuit optimum for a total capacitance of plural capacitors within the capacitor bank, thereby forming a module. One or more modules are provided corresponding to the capacitance required in the motor driving apparatus. Based on this configuration, the capability of the charging and discharging circuit and the capacitance of the capacitors are not limited by each other.

Abstract: A motor driving apparatus applicable to various types of motor driving apparatuses and having a power storage section for storing a regenerative current and supplying power to an inverter section at the time of acceleration. The motor driving apparatus further comprises a converter section, a DC link, and an inverter section, thereby driving a motor. Connected to the DC link is the power storage section including a capacitor, a charging circuit, a discharging circuit and a diode. The regenerative current produced at the motor deceleration is stored in the capacitor through the diode. The power stored in the capacitor is outputted to the DC link by turning a switching element of the discharging circuit ON at the motor acceleration. Furthermore, the charging circuit has a boost switching regulator circuit for charging the capacitor to the given upper limit voltage equal to or larger than voltage of the DC link and a current limitation circuit for limiting a charging current to the given upper limit.

Abstract: The invention is directed to the provision of a converter apparatus, an inverter apparatus, and a DC link voltage control method, wherein the upper limit value of the DC link voltage that rises due to regenerative energy occurring from a motor is set high, thereby increasing the regenerative energy to be stored in a DC link. The converter apparatus (10) comprises: a voltage detection part (11) for monitoring the DC link voltage occurring across the DC link (30); and a charge stopping part (12) for stopping charging a power storage part (C) when the detected value of the DC link voltage exceeds a predetermined upper limit voltage as the motor (3) is decelerated.

Abstract: A motor driving apparatus including a regeneration control function and a power storage device for accumulating a regenerative current and for supplying an inverter section with electric power during acceleration. The inverter section is connected to a converter section by a DC link to which regeneration start detecting means and the power storage device are connected. When the regeneration start detecting means detects that a voltage at the DC link reaches a regeneration control start voltage, a controller controls switching elements and starts regeneration control. The regenerative current is accumulated in the capacitor through a diode. When a motor is in a power running state, the switching elements are turned on to apply the voltage at the power storage device to the DC link, and the charged power is utilized for motor acceleration.

Abstract: An object of the present invention is to provide a servo motor driving apparatus and a servo motor driving method for driving a plurality of servo motors, wherein provisions are made to improve the reuse efficiency of servo motor regenerative energy. The servo motor driving apparatus (2) comprises: a plurality of inverter circuits (4, 4?, 4?) which supply AC power to the plurality of servo motors (5, 5?, 5?), respectively; a converter circuit (3) which supplies electric power in common to the inverter circuits (4, 4?, 4?); and an inverter control unit (6) which, when giving an acceleration command to any one of the servo motors, gives a deceleration command to another one of the servo motors at the same time.

Abstract: The invention is directed to the provision of a converter apparatus, an inverter apparatus, and a DC link voltage control method, wherein the upper limit value of the DC link voltage that rises due to regenerative energy occurring from a motor is set high, thereby increasing the regenerative energy to be stored in a DC link. The converter apparatus (10) comprises: a voltage detection part (11) for monitoring the DC link voltage occurring across the DC link (30); and a charge stopping part (12) for stopping charging a power storage part (C) when the detected value of the DC link voltage exceeds a predetermined upper limit voltage as the motor (3) is decelerated.

Abstract: In an inverter comprising a converter circuit that converts an alternating current into a direct current and an inverter circuit that inverts the direct current into the alternating current, supply of energy from a voltage smoothing capacitor to a load or recovery of energy from the load is facilitated without the necessity of increasing the capacitance of the voltage smoothing capacitor interposed between the converter circuit and inverter circuit. In the converter circuit, before the supply of energy to the load is started, the voltage on a dc link is raised. Before collection of energy from the load is started, the voltage on the dc link is lowered.

Abstract: A motor driving apparatus including a regeneration control function and a power storage device for accumulating a regenerative current and for supplying an inverter section with electric power during acceleration. The inverter section is connected to a converter section by a DC link to which regeneration start detecting means and the power storage device are connected. When the regeneration start detecting means detects that a voltage at the DC link reaches a regeneration control start voltage, a controller controls switching elements and starts regeneration control. The regenerative current is accumulated in the capacitor through a diode. When a motor is in a power running state, the switching elements are turned on to apply the voltage at the power storage device to the DC link, and the charged power is utilized for motor acceleration.

Abstract: A motor driving apparatus applicable to various types of motor driving apparatuses and having a power storage section for storing a regenerative current and supplying power to an inverter section at the time of acceleration. The motor driving apparatus further comprises a converter section, a DC link, and an inverter section, thereby driving a motor. Connected to the DC link is the power storage section including a capacitor, a charging circuit, a discharging circuit and a diode. The regenerative current produced at the motor deceleration is stored in the capacitor through the diode. The power stored in the capacitor is outputted to the DC link by turning a switching element of the discharging circuit ON at the motor acceleration. Furthermore, the charging circuit has a boost switching regulator circuit for charging the capacitor to the given upper limit voltage equal to or larger than voltage of the DC link and a current limitation circuit for limiting a charging current to the given upper limit.

Abstract: A compact, low-cost outage management emergency power supply device with a simple constitution is provided by connecting an auxiliary capacitor and charging battery to a DC link portion. In one embodiment, an auxiliary capacitor is connected in series via a switching circuit to a DC link portion which supplies direct-current voltage of a converter device which converts alternating-current voltage to direct-current voltage, and the input-output of current to the auxiliary capacitor is controlled by the switching circuit, so that the capacity of the additional auxiliary capacitor is not subject to limitations. Further, in another embodiment, a charging battery is connected to a DC link portion via a parallel circuit of a switching circuit or diode, and a resistor.

Abstract: A method and apparatus for controlling, in power failure, such a machine that a workpiece and a tool are required to be always synchronized in their motion. The method and apparatus allow the tool and workpiece to move back and stop at a safe area without causing any damage to them when the main power source is lost. When a power failure has happened in the middle of a synchronous operation of the motors (S1), a power regeneration function is first disabled (S2). Then a braking control command is issued so as to decelerate the tool drive motor and the workpiece drive motor while maintaining their synchronization (S3). In this step S3, the deceleration rate is controlled so that the motors regenerates energy just enough for driving the tool feed motor. The tool retracts back to an area where it is no longer engaged with the workpiece, by driving the tool feed motor with the regenerative energy produced by the deceleration of the tool drive motor and the workpiece drive motor (S4).