Circuit/System Description

The system torque coordination is provided by the hybrid powertrain control module. The engine control module (ECM) provides the accelerator pedal interface in which the driver requests a vehicle torque. These driver requests are coordinated and arbitrated within the ECM and the final driver requested torque is sent to the hybrid powertrain control module. The hybrid powertrain control module then determines how the torque output will be distributed between the two electric motors and the engine. After the torque distribution has been determined, torque reductions are imposed based upon system interrupts that are listed below:

• Vehicle stability
• Torque security
• Component overheating protection

The final arbitrated values are distributed to the system. Torque coordination of the system depends directly upon the high voltage battery pack state of charge.

This system is a distributed control system where the system torque is controlled over a system network. The system network consists of serial data communications between the controllers listed below:

• Engine control module (ECM)
• Hybrid powertrain control module 1 and 2 (HPCM 1 and 2)
• Transmission control module (TCM)
• Electronic brake control module (EBCM)
• Accessory Power Module (APM)

The hybrid powertrain control module determines the engine speed which is based on the high voltage battery pack state of charge. The ECM achieves throttle positioning by providing a pulse width modulated voltage to the throttle actuator motor. The throttle blade is spring loaded in both directions, and the default position is slightly open.