The stator of the three-phase permanent magnet synchronous motor of the new energy vehicle air conditioner requires three-phase alternating current to drive, but the vehicle directly provides only high-voltage direct current to the compressor, so a special inverter for air conditioners is required to convert the direct current into alternating current.
A common electric air conditioner inverter uses 6 IGBT field effect transistors. It is an insulated gate bipolar transistor and is a voltage control device. It is characterized by small gate driving power and low saturation voltage. It is used in power systems and converters. Technically widely used. The turn-on or turn-off of the IGBT tube is controlled by the gate voltage on it, which can cause a path or disconnection between the source and drain of the IGBT. As shown in the figure below, when the mode poles of each IGBT take turns to add the duty cycle pulse modulation control voltage according to a certain rule, the DC high-voltage current of the battery will pass through the inverter, forming a three-phase sinusoidal AC current at the output end, which is beneficial to the three-phase The phase permanent magnet synchronous motor runs smoothly and generates torque to drive the air conditioning compressor. The diode connected in parallel with the IGBT tube in the picture is the freewheeling diode of the three-phase winding of the motor, which plays the role of protecting the IGBT tube.