Circuit/System Description

WARNING: This page is about a different car, the 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.

The drive motor generator power inverter control module contains two motor control modules and the hybrid powertrain control module. Each motor control module operates its respective drive motor generator based upon hybrid powertrain control module commands. Each motor control module controls the speed, direction and output torque of its respective drive motor generator through the sequencing actuation of high current switching transistors called insulated gate bipolar transistors. Each drive motor generator operates utilizing 3 phase alternating current (AC) electricity. Each insulated gate bipolar transistors operate a single phase of the drive motor generator. Each phase is individually identified as U, V and W. Each motor control module monitors the current of each phase in order to detect drive motor generator power inverter control overcurrent conditions.

At ignition ON, each motor control module tests the integrity of the drive motor phase circuits by sequencing the insulated gate bipolar transistors between open and shorted states while simultaneously injecting a large amount of current into the phase circuits. The individual phase current sensors should all indicate similar current flow and the current flow should increase and decrease at known rates based upon the inductance of the drive motor.