The invention relates to a method for determining a characteristic curve of a hybrid separating clutch of a hybrid vehicle without a test stand, wherein the hybrid separating clutch separates or connects an internal combustion engine and an electric motor and the hybrid separating clutch is slowly actuated on the basis of a position which the hybrid separating clutch assumes in an unactuated state, and a clutch characteristic curve is determined as a function of a clutch torque over a path of the hybrid separating clutch. In a method by which a characteristic curve of the hybrid separating clutch can be reliably defined without a test stand, a clutch torque which underlies the characteristic curve of the hybrid separating clutch is determined from the torque of the internal combustion engine in the case of a running internal combustion engine and a motion state of the electric motor which brakes the internal combustion engine while the hybrid separating clutch is moving.

A slip control method and arrangement for a drivetrain including a continuously variable transmission, forward-reverse clutch arrangement and an optional three-speed gearbox is described herein. The forward-reverse clutch arrangement includes a clutch that is so controlled as to slip when a torque higher than the usable torque attempts to pass through. Accordingly, the clutch prevents the prime mover from stalling.

A method of controlling a powertrain of a vehicle is carried out such that during shifting in which a first clutch is released and a second clutch is engaged, whether a current shift phase is a torque phase or an inertia phase is determined. Different cost functions for the torque phase and the inertia phase are predefined. A control input change for minimizing the cost functions in the torque phase and the inertia phase is calculated. At least two among input torque, first clutch torque, or second clutch torque input to a transmission are controlled by applying the control input change calculated for the torque phase and the inertia phase.

A power transmission device includes a friction clutch, an actuator, and a controller configured to determine an approximated temperature change of the friction clutch. The controller is configured to determine a current power state of the friction clutch, determine a desired power state change based on the current power state and a previous power state, determine a plurality of thermal coefficients based on a thermal coefficient model, the desired power state change, and a set of operation variables, determine an approximated temperature change of the friction clutch based on the thermal coefficients and a friction clutch temperature model, determine an approximated clutch temperature based on the approximated temperature change and a contemporaneous value of an device ambient temperature, and control operation of the actuator based at least on the approximated clutch temperature.

A hybrid vehicle includes an electric motor and a combustion engine. A K0 clutch couples the combustion engine to a drivetrain of the vehicle. A control module of the vehicle calculates a torque to be applied by the motor to the K0 clutch when initiating engagement of the combustion engine to the drivetrain. The control module calculates two separate torque lead values by two separate methods and calculates the torque by combining the two torque lead values.

A hybrid vehicle includes an electric motor and a combustion engine. A K0 clutch couples the combustion engine to a drivetrain of the vehicle. A control module of the vehicle calculates a torque to be applied by the motor to the K0 clutch when initiating engagement of the combustion engine to the drivetrain. The control module calculates two separate torque lead values by two separate methods and calculates the torque by combining the two torque lead values.

A method of controlling a clutch for vehicle may include determining, by a controller, raised offset engine torque, when engine torque is raised to a reference torque or more in an engine idle state, and controlling, by the controller, the clutch based on the determined offset engine torque.

A method to estimate an amount of force in a clutch pack of a clutch actuation system. The method includes engaging an actuation motor to apply a set point force to the clutch pack and monitoring a position of the actuation motor when the set point force is applied. Additionally, the method includes determining one or more clutch clamping curves and one or more clutch releasing curves based on a relationship between the position of the actuation motor and an amount of torque applied by the actuation motor at position of the actuation motor. The method further includes modeling one or more frictional characteristics of the clutch actuation system and estimating an amount of clamping and releasing force within the clutch pack by using a control unit. The amount of torque applied to the clutch pack between the clutch clamping and releasing curves at the set point force is maintained.

Methods are provided for checking the actuating accuracy of a clutch arranged in a force flow between a fixable shaft and an electric machine of an electric or hybrid motor vehicle when at a standstill. One method includes: fixing the shaft, setting a defined setpoint torque on the clutch to be checked, continuously ramping up the electric machine up until the first slipping of the clutch, comparing the achieved torque of the electric machine with the setpoint torque preset on the clutch. Another method includes: fixing the shaft, ramping up the electric machine to a defined rotational speed, setting a defined setpoint torque on the clutch to be checked, comparing the torque of the electric machine needed to maintain a constant rotational speed with the setpoint torque set on the clutch.

An apparatus and method of using the apparatus for learning a clutch torque of a Dual Clutch Transmission (DCT) includes judging whether shifting begins, controlling torque transmission of a coupling-side clutch and a release-side clutch to cross each other while following a coupling-side target clutch torque when shifting begins, and calculating and storing a learning value, after the controlling has begun, using a function determined by the relationship between an average value of an engine angular acceleration and a coupling-side shifter input-shaft angular acceleration, engine rotation inertia, and a torque compensated to the torque transmission of the coupling-side clutch for reducing a slippage of the release-side clutch by feedback control during a torque handover interval.