ASYNCHRONOUS-TO-SYNCHRONOUS CLUTCH TORQUE EXCHANGE IN A HYBRID ELECTRIC VEHICLE

摘要

A vehicle includes torque sources, a transmission, and a controller programmed to execute a method. In executing the associated method, the controller determines whether continuous output torque is required through a torque exchange. When continuous output torque is required, the controller synchronizes and fills the oncoming clutch, estimates capacity of the oncoming clutch, and expands a short-term torque capacity of the oncoming clutch during the torque exchange, doing so in response to a control objective having a threshold priority. Onset of the torque exchange delays until the short-term torque capacity is sufficient for receiving all torque load from the offgoing clutch without affecting output torque. The controller asynchronously controls the offgoing clutch and synchronously controls the oncoming clutch through the torque exchange, and loads the synchronous oncoming clutch via an expanding set of long-control torque capacity limits as a function of a simultaneously exhausting of the offgoing clutch load.

主权项

1. A hybrid electric vehicle comprising:
a plurality of torque sources; a transmission having:
a gear set; anda plurality of clutches including an offgoing clutch and an oncoming clutch; and a controller in communication with the transmission and the torque sources, wherein the controller is configured to:
determine whether continuous output torque is required through a duration of a torque exchange commanded via a requested shift; andwhen the continuous output torque is required:
synchronize and fill the oncoming clutch;estimate a hydraulic capacity of the oncoming clutch;temporarily expand a short-term torque capacity of the oncoming clutch during the duration of the torque exchange in response to a control objective having a threshold priority;delay onset of the torque exchange until the short-term torque capacity of the oncoming clutch is sufficient for receiving all torque load from the offgoing clutch without affecting the continuous output torque;asynchronously control the offgoing clutch through the duration of the torque exchange;synchronously control the oncoming clutch through the duration of the torque exchange; andload the synchronous oncoming clutch via an expanding set of long-control torque capacity limits as a function of a simultaneously exhausting the offgoing clutch load.