JP2016174473A5 - Work machine, converter device - Google Patents

Claims (10)

  An electric motor used as a drive unit of a work machine;
  An inverter for driving the electric motor;
  A converter connected to the inverter;
  A controller for determining an abnormality of a capacitor connected between the inverter and the converter at the time of starting the work machine;
  An informing unit for informing when there is an abnormality,
  A work machine comprising:   2. The work machine according to claim 1, wherein the control unit determines an abnormality of the capacitor based on a capacitance value of the capacitor calculated when the work machine is started and a predetermined threshold value.   2. The work according to claim 1, wherein the control unit starts initial charging of the capacitor when the work machine is started, and determines abnormality of the capacitor based on a rising waveform of a voltage value of the capacitor. machine.   When initially charging the capacitor, comprising a discharge resistor connected to a path between the capacitor and a power source that supplies power to the capacitor;
  The control unit calculates a resistance value of a discharge resistor that eliminates the abnormality or a resistance value of a discharge resistor that should be added to eliminate the abnormality, and causes the notification unit to notify the controller. The work machine according to 1.   5. The work machine according to claim 1, wherein when the abnormality occurs, the control unit stops the initial charging of the capacitor. 6. An output terminal to which a load including an input capacitor is connected;
A DC / DC converter including a reactor, a switching element and a smoothing capacitor connected to the output terminal, and generating a DC link voltage at the output terminal;
A main switch provided between an input terminal of the DC / DC converter and a storage means;
A charging resistor provided in parallel with the main switch;
An abnormality detection unit for determining whether or not the capacitance of the input capacitor connected to the output terminal is smaller than an allowable value;
A converter device comprising: The converter device according to claim 6 , wherein the abnormality detection unit determines whether or not the capacitance of the input capacitor is smaller than an allowable value based on a rising waveform of the DC link voltage. The abnormality detection unit is configured such that the capacitance of the input capacitor is smaller than an allowable value based on whether or not the DC link voltage exceeds a threshold voltage within a predetermined time after charging of the smoothing capacitor and the input capacitor is started. The converter device according to claim 6, wherein it is determined whether or not. The abnormality detection unit determines whether the capacity of the input capacitor is based on whether the time required for the DC link voltage to exceed a predetermined voltage after the start of charging of the smoothing capacitor and the input capacitor is longer than a predetermined time. The converter device according to claim 6, wherein it is determined whether or not the allowable value is smaller. Further comprising a relay connected in series with the charging resistor in a path parallel to the main switch,
The converter device according to claim 6 , wherein the relay is turned off when the capacitance of the input capacitor is larger than the allowable value.