Traction Motor Inverter

COMPONENT PARTS

Traction Motor Inverter

NOTE:
Control of the traction motor and control of EV system CAN communications with other control modules is actually performed by the motor controller. However, because the motor controller is installed inside the traction motor inverter, the motor controller is here referred to as the traction motor inverter.
- The traction motor inverter is composed of the motor controller, driver, smoothing condenser, 3 current sensors, and power module.
- The traction motor inverter controls the traction motor based on the target motor torque signal transmitted by EV system CAN from the
VCM.
- Traction motor inverter drives traction motor accurately based on resolver detection signal and current sensor detection signal.
- The traction motor inverter performs charging judgment for the high voltage circuit and also discharges the voltage inside the circuit.





- The traction motor inverter performs vibration control in order to improve accelerator response and provide good acceleration while driving.

MOTOR CONTROLLER

- The motor controller receives the rotor rotation angle from the traction motor resolver and the traction motor current value from the current sensor, and creates the pulse signal for driving the IGBT (Insulated Gate Bipolar Transistor).
- The motor controller detects the traction motor temperature by means of the traction motor temperature sensor, and limits the output torque (protection control) according to the level of heat in the traction motor.

DRIVER

The driver converts the pulse signal (12 V) from the motor controller to a high voltage signal (300 V) and drives the IGBT.

POWER MODULE

- The power module is composed of 6 power semiconductor IGBTs.
- An IGBT is a semiconductor switch that is capable of switching ON/OFF at high speed.
- An IGBT uses the IGBT drive signal from the driver to perform switching, converting the Li-ion battery DC
power to AC power and supplying AC power to the traction motor.

SMOOTHING CONDENSER

The smoothing condenser controls the voltage ripple which occurs as a result of IGBT switching.

CURRENT SENSORS

One sensor each is installed at the U-phase, V-phase, and W-phase. They detect the current supplied to the traction motor and send the current values as feedback to the motor controller.

DISCHARGE RESISTER

The discharge resistor discharges the high voltage in case the traction motor inverter is unable to discharge the remaining high voltage in the high voltage circuit due to a malfunction.