Circuit/System Description

WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.

The drive motor generator power inverter module contains two motor control modules and the hybrid powertrain control module. Each motor control module operates its respective drive motor based upon hybrid powertrain control module commands. Each motor control modules 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 AC electricity. Each insulated gate bipolar transistors operates a single phase of the drive motor generator. Each phase is individually identified as U, V and W. Each motor control modules monitors the current of each phase in order to detect drive motor generator power inverter module over current conditions.

Because all the motor generator phase circuits are electrically joined together, they should each flow about the same amount of current. The motor control modules perform a mathematical calculation to verify that the phase current sensors are accurate. If the U-V-W phase current sensors indicate about the same amount of phase current, the sum of the calculation should be near zero. If the U-V-W phase currents are not similar, this DTC will set.