Inverter having a function of detecting a failure of a power component, and methods of detecting a failure of a power device

摘要

An inverter apparatus comprising: an inverter for converting an AC voltage to a DC voltage; a DC link capacitor connected to the inverter; a voltage detector for DC link voltage; a charging circuit for the DC link capacitor; a charging circuit control device for a switch connected to a charging resistor; a current detector for detecting a current of the inverter; a turn-on control device for controlling the turn-on of power devices; a switch for connecting or disconnecting a power supply; a power monitor for monitoring a connection state of the power supply; a threshold adjuster for setting a first or second threshold; and a defect detector for determining the presence or absence of a defect of the power devices by comparing between a current flowing upon turning on of the power device immediately after the disconnection of the power supply and the first or second threshold.