Method and apparatus to stabilize engine state selection using an energy based stabilization strategy for hybrid powertrain systems

摘要

A method for controlling operation of a multi-mode powertrain system includes periodically determining a power cost difference between a first power cost and a second power cost. This includes determining the first power cost associated with operating the powertrain system with the engine operating in a presently commanded engine state in response to an operator torque request and determining the second power cost associated with an expected powertrain operation with the engine operating in a non-commanded engine state in response to the operator torque request. The first power cost is compared with the second power cost, and successive iterations of the periodically determined power cost difference between the first power cost and the second power cost are integrated to determine an integrated power cost difference. A transition to the non-commanded engine state is commanded when the integrated power cost difference is greater than a threshold.