Control Strategy and Energy Recovery Potential for P2 Parallel Hybrid Step Gear Automatic Transmissions 2019-01-1302
The purpose of this investigation is to present a control strategy and energy recovery potential for P2 parallel hybrid step gear automatic transmissions. The automatic transmission types considered for the investigation are rear wheel drive a dual clutch transmission and a 10 speed planetary automatic equipped each equipped with a significant electric motor between the engine and transmission. The governing equations of clutch-to-clutch upshift controls are presented for each transmission type and various strategies are explored for executing the upshift under various input torque levels, shift times and engine torque management approaches. A lumped parameter dynamic model including the P2 electrification system is utilized for each transmission type to represent dynamic behavior representative of that expected in vehicle for achieving various levels of shift quality assessed with vibration dose value. The shift quality and energy recovery potential are highlighted for various upshift maneuvers on a per shift basis as well as overall cumulative energy recovery potential on real world as well as regulatory test cycles.