Abstract: Disclosed is a method of diagnosing inverter trouble capable of improving convenience of use and safety of the user by notifying the user of the error of switching devices used for outputting AC voltage of the inverter and the earth fault of an output of the inverter when applying power to the inverter.

Abstract: An apparatus for detecting a fault of a cooling fan includes an electronic switch connected to a negative (?) power input terminal of a cooling fan and turning on/off the cooling fan; a current detector connected to the electronic switch and detecting a current value of the cooling fan; an analog filter for filtering the detected current value; and a controller for converting the filtered current value into a digital current value and determining whether the cooling fan is improperly operated based on the converted digital current value and a pre-set upper threshold value and lower threshold value.

Abstract: Disclosed is a method of diagnosing inverter trouble capable of improving convenience of use and safety of the user by notifying the user of the error of switching devices used for outputting AC voltage of the inverter and the earth fault of an output of the inverter when applying power to the inverter.

Abstract: Disclosed is a circuit for driving a gate of an IGBT (insulated gate bipolar transistor) inverter. The present invention includes a first IGBT of which collector is connected to a DC voltage, a second IGBT of which collector is connected to an emitter of the first IGBT, wherein an output signal is outputted from a connection point between the collector of the second IGBT and the emitter of the first IGBT, and of which emitter is connected to a ground, first and second driving circuits supplying gates and the emitters of the first and second IGBTs with DC driving voltages, respectively, through first and second gate resistors, and first and second noise interruption circuits connected between the gates-emitters of the first and second IGBTs and the first and second driving circuits, respectively, so as to interrupt noises.

Abstract: Disclosed is a circuit for driving a gate of an IGBT(insulated gate bipolar transistor) inverter. The present invention includes a first IGBT of which collector is connected to a DC voltage, a second IGBT of which collector is connected to an emitter of the first IGBT, wherein an output signal is outputted from a connection point between the collector of the second IGBT and the emitter of the first IGBT, and of which emitter is connected to a ground, first and second driving circuits supplying gates and the emitters of the first and second IGBTs with DC driving voltages, respectively, through first and second gate resistors, and first and second noise interruption circuits connected between the gates-emitters of the first and second IGBTs and the first and second driving circuits, respectively, so as to interrupt noises.