Abstract:
In a motor driver of the present invention, voltage and current values measured by a voltage and current detector and a voltage value measured by a voltage detector are determined as first measurement results, in the state of turning on semiconductor switching elements connected between a positive terminal of a capacitor and motor coils. Voltage and current values measured by the voltage and current detector and a voltage value measured by the voltage detector are determined as second measurement results, in the state of, as to a group A, turning on a semiconductor switching element connected between the positive terminal of the capacitor and the motor coil, and as to a group B, turning on semiconductor switching elements connected between a negative terminal of the capacitor and the motor coil. The insulation resistance values are calculated between the motor coils of each group A or B and a ground.
Abstract:
A motor drive apparatus includes a converter, a DC link capacitor, a plurality of inverters, a diagnosis command unit configured to give a command to one of the plurality of inverters to perform power conversion, an AC voltage detection unit configured to detect a peak value of AC voltage on an AC input side of the converter, a DC voltage detection unit configured to detect a value of DC voltage across the DC link capacitor, a calculation unit to calculate a difference between the value of DC voltage and the peak value of AC voltage, a storage unit configured to store the difference in association with the inverters, and a leakage current determination unit configured to determine that the inverter associated with the largest of the differences stored in the storage unit is the inverter that has caused the largest leakage current.
Abstract:
A motor drive according to the present invention includes an inverter, a motor rotational speed obtaining unit, a motor inertia information storage unit, a motor rotational energy calculator, a dynamic braking circuit, a tolerance information storage unit for storing the tolerances of resistors of the dynamic braking circuit, a power element operation unit, a dynamic braking circuit operation unit, and a tolerance comparator for performing a comparison between the rotational energy of a motor and the tolerance of the dynamic braking circuit. When the rotational energy exceeds the tolerance, power elements of one of arms are turned on, while power elements of the other arm are turned off, without actuating the dynamic braking circuit. When the rotational energy is equal to or less than the tolerance, the dynamic braking circuit is actuated, and the power elements of the one of the arms are turned off.
Abstract:
A motor drive device includes a power source unit rectifying AC voltage to DC voltage and to smooth the DC voltage by a capacitor, a motor drive amplification, a power source voltage measurement unit, an insulation resistance deterioration detection unit having a contact unit connecting one end of the capacitor to the ground and a current detection unit provided between the other end of the capacitor and a motor coil, and detecting a deterioration in an insulation resistance of the motor based on a detected signal obtained from a closed circuit formed by the contact unit, the capacitor, the motor coil, and the ground by using the current detection unit, and a failure detection unit detecting a failure in the insulation resistance deterioration detection unit based on the detected signal in the insulation resistance deterioration detection unit and a voltage value measured by the power source voltage measurement unit.
Abstract:
A resin molded substrate has at least a pair of terminal through holes for allowing lead terminals of a cylindrical capacitor to be inserted through, and at least one protrusion for supporting a side of a bottom portion of the capacitor so as to space from a front surface of the substrate the side of the bottom portion of the capacitor having the lead terminals inserted through the terminal through holes. The pair of lead terminals at the bottom portion are inserted through the terminal through holes of the resin molded substrate, whereby the capacitor is mounted in an upright state with a solder, so that the protrusion spaces the side of the bottom portion from the front surface of the resin molded substrate.
Abstract:
A motor drive apparatus includes a converter configured to convert AC power inputted by an AC power supply to DC power and to output the same to a DC link, a DC link capacitor provided for the DC link, an inverter configured to convert the DC power in the DC link to AC power for driving a motor and to output the AC power, a DC voltage detection unit configured to detect a value of DC voltage applied across the DC link capacitor, an AC voltage detection unit configured to detect a peak value of AC voltage on an AC input side of the converter, and a leakage current detection unit configured to detect a leakage current caused by driving the motor, based on the value of DC voltage detected by the DC voltage detection unit and the peak value of AC voltage detected by the AC voltage detection unit.
Abstract:
A motor drive apparatus includes a converter configured to convert AC power of an AC power supply into DC power and outputs the DC power, a DC link unit including capacitors connected in series with each other, an inverter connected in parallel with the DC link unit, and configured to convert the DC power of the DC link unit into AC power for driving a motor, and outputs the AC power, and a short-circuit judgment unit configured to judge that at least one of the capacitors in the DC link unit has shorted in the case where, when the value of a voltage applied to a positive and negative bipolar terminal of the DC link unit is smaller than a first threshold, the value of an input current flowing from the AC power supply into the DC link unit via the converter is larger than a second threshold.
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 of the present invention includes: a rectification circuit configured to rectify an AC voltage; a power source unit configured to smooth a DC voltage by a capacitor; an inverter unit configured to drive a motor by converting a DC voltage into an AC voltage; a current detection unit configured to measure a current flowing through a resistor which is connected to a coil of the motor and the capacitor; a voltage detection unit configured to measure a value of a voltage across the capacitor; a second switch that grounds the capacitor; and an insulation resistance detection unit configured to detect an insulation resistance value of a motor by using two sets of a current value and a voltage value measured in two states where the second switch is turned off and turned on.
Abstract:
A monitoring device includes: an acquisition unit for acquiring a clock signal output from a communication circuit that outputs the clock signal; and a monitoring unit for analyzing the waveform of the clock signal acquired by the acquisition unit, based on a predetermined reference clock signal having a period equal to or shorter than a period of the clock signal to thereby determine whether or not there is a sign of malfunction in the communication circuit.