Abstract: A current detection circuit includes: a resistor in a current path; first and second signal transmission units that transmit signals of first and second terminal sides of the resistor; a first difference operation unit that executes a difference operation on the signals transmitted by the first and second signal transmission units; a noise-capturing transmission unit starting point; third and fourth signal transmission units connected with the noise-capturing transmission unit starting point; a second difference operation unit that executes a difference operation on the signals transmitted by the third and fourth signal transmission units; and a summing operation unit that executes a summing operation on the first and second difference signals, wherein the first signal transmission unit and the fourth signal transmission unit are disposed close to each other and the second signal transmission unit and the third signal transmission unit are disposed close to each other.

Abstract: A motor driving apparatus includes a motor driving unit for converting DC voltage on a DC link into AC voltage when a switching device is turned on/off and outputting the AC voltage to an AC motor side, a gate driving circuit for turning on/off the switching device, a gate driving command generation unit for outputting either one of an ON command and an OFF command to the gate driving circuit, and an overcurrent detection unit for detecting an overcurrent with respect to a DC link current or an alternating current on the AC motor side, wherein, when the overcurrent detection unit detects the overcurrent, the gate driving command generation unit alternately outputs the ON command and the OFF command while gradually increasing a ratio of the OFF command to the ON command and ultimately outputs only the OFF command.

Abstract: A motor drive apparatus according to the present invention comprises: an electric shunt which shunts a current flowing through a power line connected to a motor; a first current detection unit and a second detection unit, each disposed on either side of a node shunted by the electric shunt, for detecting the current flowing through the power line; a shunt commanding unit which gives a shunt command to the electric shunt to effect shunting of the current; and a determining unit which determines the presence or absence of a fault in the electric shunt, based on the shunt command and on current values detected by the first current detection unit and the second detection unit.

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 printed circuit board according to an embodiment of the present invention is formed of an insulating material and configured to mount components and wiring thereon. The printed circuit board includes a liquid pool for storing a liquid; a pair of deterioration detection traces one of which is connected to a power supply at one end and disposed in the liquid pool at the other end, and the other of which is connected to a ground at one end through a resistor and disposed in the liquid pool at the other end; a voltage detection circuit for detecting a voltage between the one ends of the one and the other deterioration detection traces; and a deterioration determination circuit for determining, based on the detected voltage, whether or not insulation deteriorates between the other ends of the one and the other deterioration detection traces.

Abstract: To provide a motor drive device that suppresses voltage fluctuation of a DC link capacitor, as well as enabling for low cost and size reduction. A motor control unit sets a threshold of voltage at which to start regeneration to a first threshold in a case of an increased amount per unit time of a DC voltage value detected by a voltage detection part being less than a certain amount, and sets the threshold of voltage at which to start regeneration to a second threshold that is larger than the first threshold, in a case of the increased amount per unit time of the DC voltage value detected by the voltage detection part being at least a certain amount.

Abstract: A robot includes a motor drive power source for converting a voltage supplied from a power source to a motor drive unit-grade voltage and outputting it, a motor drive unit for converting a motor drive unit-grade voltage output from the motor drive power source to a motor drive voltage and outputting it, a motor driven to be rotated by a motor drive voltage output by the motor drive unit, a robot arm on which the motor drive unit and the motor are arranged, and a robot controller which is provided independently of the robot arm and on which the motor drive power source is arranged.

Abstract: A motor drive includes a DC power supply unit for rectifying electric power supplied from an AC power supply using a rectifier and smoothing the electric power using a capacitor; and a plurality of independent voltage measurement circuits for measuring the voltage of the DC power supply unit. The motor drive, which converts a DC voltage into an AC voltage to drive a motor, includes a voltage collection unit for collecting voltage information obtained from the voltage measurement circuits; a normal operation voltage information storage unit for storing a normal operation voltage; and an abnormality determination unit for identifying an intersection voltage of output signals based on voltage values collected by the voltage collection unit, comparing the intersection voltage with the normal operation voltage, and detecting a broken portion owing to entering foreign matter based on the difference between the intersection voltage and the normal operation voltage.

Abstract: A motor drive apparatus in which a main power supply used for motor drive is supplied via a magnetic contactor includes: a monitoring unit that monitors a main power supply voltage at an AC power supply input side of the magnetic contactor in a state in which contacts of the magnetic contactor are opened; a determination unit that determines whether the main power supply voltage monitored by the monitoring unit is normal; and a magnetic contactor control unit that outputs a command that controls opening and closing of contacts of the magnetic contactor, wherein when it is determined by the determination unit that the main power supply voltage is abnormal, the magnetic contactor control unit maintains an output of an open command such that the contacts of the magnetic contactor are opened.

Abstract: A motor drive apparatus includes: a motor current detection unit; a brake release determination unit that determines that the brake is not released when the motor current detected when the motor is operated under a predetermined load by application of a voltage to a brake coil is larger than a current for when the brake is normally released; a brake coil voltage change unit that changes a voltage applied to the brake coil when it is determined that the brake is not released to a larger value; a change history storage unit that stores the voltage after being changed and change date and time; and a life prediction unit that calculates a predicted life of the brake apparatus based on the voltage after being changed and the change date and time and the previously stored failure-time brake coil voltage.

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 system enabling detection of cutting fluid deposited at a housing of electronic components. A housing holding electronic components of a motor drive system has top faces slanted with respect to the horizontal plane so as to guide the deposited cutting fluid. The housing further includes storage parts collecting the cutting fluid guided along the top faces. The storage parts may be graduated so as to enable the collected amount of the cutting fluid to be measured. The storage parts may be configured to be detachable from the housing.

Abstract: A motor driving apparatus includes a motor driving unit for converting DC voltage on a DC link into AC voltage when a switching device is turned on/off and outputting the AC voltage to an AC motor side, a gate driving circuit for turning on/off the switching device, a gate driving command generation unit for outputting either one of an ON command and an OFF command to the gate driving circuit, and an overcurrent detection unit for detecting an overcurrent with respect to a DC link current or an alternating current on the AC motor side, wherein, when the overcurrent detection unit detects the overcurrent, the gate driving command generation unit alternately outputs the ON command and the OFF command while gradually increasing a ratio of the OFF command to the ON command and ultimately outputs only the OFF command.

Abstract: A motor drive device assembly capable of suppressing differences in temperatures of motor drive devices depending on operational conditions. The motor drive device assembly includes a first motor drive device including a first heatsink, a second motor drive device located adjacent to the first motor drive device and including a second heatsink formed separately from the first heatsink, and a connection part connecting the first heatsink and the second heatsink to each other, to allow thermal conduction between the first heatsink and the second heatsink.

Abstract: A motor drive apparatus according to the present invention comprises: an electric shunt which shunts a current flowing through a power line connected to a motor; a first current detection unit and a second detection unit, each disposed on either side of a node shunted by the electric shunt, for detecting the current flowing through the power line; a shunt commanding unit which gives a shunt command to the electric shunt to effect shunting of the current; and a determining unit which determines the presence or absence of a fault in the electric shunt, based on the shunt command and on current values detected by the first current detection unit and the second detection unit.

Abstract: An apparatus with a motor drive device is provided with a support plate including an opening part for supporting the motor drive device. The support plate includes a first edge part around the opening part and a second edge part on the opposite side of the first edge part. The motor drive device includes a first recessed part formed on one end part in a predetermined direction, and a second recessed part formed on the other end part on the opposite side of the one end part. The first edge part is inserted into the first recessed part, and the second edge part is inserted to the second recessed part.

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 drive includes a DC power supply unit for rectifying electric power supplied from an AC power supply using a rectifier and smoothing the electric power using a capacitor; and a plurality of independent voltage measurement circuits for measuring the voltage of the DC power supply unit. The motor drive, which converts a DC voltage into an AC voltage to drive a motor, includes a voltage collection unit for collecting voltage information obtained from the voltage measurement circuits; a normal operation voltage information storage unit for storing a normal operation voltage; and an abnormality determination unit for identifying an intersection voltage of output signals based on voltage values collected by the voltage collection unit, comparing the intersection voltage with the normal operation voltage, and detecting a broken portion owing to entering foreign matter based on the difference between the intersection voltage and the normal operation voltage.

Abstract: A motor drive device is capable of allowing a user to surely recognize that effect when a cutting fluid adheres to a casing. The motor drive device includes an electronic component and a casing that houses the electronic component. A part of the casing changes color when coming in contact with a cutting fluid and the casing may change to different colors based on the concentration of the cutting fluid.