Abstract: A continuously variable transmission, a control system, and a method is provided for synchronizing a clutch application state change and a continuous upshift in a motor vehicle propulsion system having a continuously variable transmission (CVT). The control system and method are configured to determine whether a continuous upshift of the CVT is impending. The continuous upshift is defined as a pulley ratio change exceeding a predetermined threshold for a predetermined pulley ratio change period. If a continuous upshift is impending, the control system and method are configured to alter a clutch engagement state after a predetermined delay period to synchronize the change in clutch engagement state with an engine speed change.

Abstract: A continuously variable transmission, a control system, and a method are provided. The control system and method are configured to learn a desired running pressure to be applied to a clutch that is lower than a pulley clamping pressure and higher than a pressure at which the clutch would slip (a clutch critical pressure), so that the clutch can act as a fuse to avoid pulley slip. A plurality of clutch slip tests are performed, each of which include decreasing pressure supplied to the clutch until a clutch slip occurs. Clutch slip data points are collected at the point of slip and used to determine a gain and an offset, where the gain is a clutch pressure versus clutch torque capacity gain, and the offset is a clutch pressure offset, which is used to determine the clutch critical pressure.

Abstract: A method of controlling a clutch-to-clutch power-on upshift of a transmission includes defining a possible engine torque as a latched possible engine torque value. An on-coming clutch torque phase target value is defined as a latched on-coming clutch torque value, and held constant until a final ramp. A commanded engine torque is reduced and maintained to a maximum torque reduction value until a shift completion ratio is achieved. The commanded engine torque is increased until the commanded engine torque is equal to a restore ramp target value. Both the on-coming clutch torque and the commanded engine torque are simultaneously increased at a final ramp rate, such that the increase in the on-coming clutch torque parallels the increase in the commanded engine torque, until an actual engine torque is substantially equal to the possible engine torque, to complete the shift.

Abstract: A method of controlling a clutch-to-clutch power-on upshift of a transmission includes defining a possible engine torque as a latched possible engine torque value. An on-coming clutch torque phase target value is defined as a latched on-coming clutch torque value, and held constant until a final ramp. A commanded engine torque is reduced and maintained to a maximum torque reduction value until a shift completion ratio is achieved. The commanded engine torque is increased until the commanded engine torque is equal to a restore ramp target value. Both the on-coming clutch torque and the commanded engine torque are simultaneously increased at a final ramp rate, such that the increase in the on-coming clutch torque parallels the increase in the commanded engine torque, until an actual engine torque is substantially equal to the possible engine torque, to complete the shift.