Integrated Powertrain Controller Optimizing Shifting via Cost Function

The patent merges independent engine control and transmission control into a unified powertrain control system. The controller receives driver intent signals and vehicle state information, then simultaneously determines optimal engine output and transmission shifting decisions based on a cost function that evaluates fuel efficiency, drivability, and component constraints. This integrated approach optimizes overall vehicle performance rather than controlling each component separately.

Instead of creating multiple fixed transmission maps for different driving states, the patent uses a cost function with adjustable parameters (weights for fuel efficiency, drivability, and constraint satisfaction) that dynamically adapts to various conditions. The controller evaluates different shifting scenarios by computing fuel consumption, drivability metrics, and constraint violations, then selects the optimal shifting decision based on the weighted cost function, eliminating the need for pre-defined maps.

The patent dynamically adjusts the cost function parameters based on vehicle operating conditions. When the vehicle is in steady-state cruising conditions, the cost function heavily weights fuel efficiency to encourage higher gear selection. When acceleration demands or frequent shifting are detected, the drivability weight increases, allowing the controller to maintain lower gears and reduce shifting frequency, thus balancing fuel efficiency and drivability based on real-time conditions.

The patent combines transmission shifting control with engine output management in a unified control framework. When the controller determines an optimal shifting decision, it simultaneously adjusts engine torque requests to compensate for the changing gear ratio, maintaining consistent delivered power to the wheels. This integrated approach eliminates the need for driver intervention to maintain engine output during shifting events.