A hybrid vehicle includes an engine, an electric machine, a disconnect clutch configured to selectively couple the engine to the electric machine, and a controller. The controller is programmed to, in response to a request to start the engine with the electric machine, command a target pressure to the disconnect clutch that depends on a seal friction derived from a measured line pressure of the disconnect clutch and a rate change of the measured line pressure.

A method and system for controlling clutch friction elements of an automatic transmission is provided. The method includes retrieving information about shift clutches from a data storage unit and acquiring information required to predict a temperature of a friction element for each shift clutch, deriving a predicted temperature value of a friction element for each shift clutch by using the information about the shift clutches and the information required to predict the temperature of the friction element, predicting whether or not overheating occurs for each shift clutch by comparing the derived predicted temperature value of the friction element for each shift clutch with an allowable temperature set for each shift clutch, and determining a target shift stage while avoiding the overheating clutch with a predicted temperature value exceeding the allowable temperature, through switching to an avoidance shift mode.

Embodiments of the present invention provide a control system (200) for an electric machine (120) of a vehicle, the control system comprising one or more controllers, the control system comprising input means (230) to receive a torque communication signal (255) indicative of torque communication through a belt (130) associated with the electric machine, processing means (210) arranged to determine a torque limit for the electric machine in dependence on the torque communication signal and a first torque threshold, and output means (240) arranged to output a torque limit signal (245) in dependence on the torque limit to control the torque communicated through the belt associated with the electric machine.

A four-wheel drive vehicle includes: (a) main drive wheels and auxiliary drive wheels; (b) a rotating machine as a drive power source; (c) a drive-power distribution clutch configured to allocate a part of a drive power outputted to the main drive wheels from the drive power source, to the auxiliary drive wheels, so as to distribute the drive power to the main drive wheels and the auxiliary drive wheels with a drive-power distribution ratio between the auxiliary drive wheels and the main drive wheels, such that the drive-power distribution ratio is variable with an engaging force of the drive-power distribution clutch being controlled; and (d) a control apparatus configured, when determining that a heat load of the drive-power distribution clutch is large during deceleration running of the vehicle, to limit a regenerative torque of the rotating machine, as compared with when determining that the heat load is small.

A vehicle includes an engine, a primary axle drivably connected to the engine, and a secondary axle drivably connected to the engine by a clutch. A controller is programmed to, in response to map data indicating that the vehicle is off-road, enable an off-road transfer torque control mode in which temperatures of the clutch are compared to a lower threshold. The controller is further programmed to, in response to the temperature of the clutch exceeding the lower threshold, display a message to a driver indicative of rising temperatures of the clutch, and, in response to a temperature of the clutch exceeding an upper limit, enable a power limiting mode in which torque of the engine is limited to a predefined value.

A four-wheel drive vehicle includes: (a) main drive wheels and auxiliary drive wheels; (b) a rotating machine as a drive power source; (c) a drive-power distribution clutch configured to allocate a part of a drive power outputted to the main drive wheels from the drive power source, to the auxiliary drive wheels, so as to distribute the drive power to the main drive wheels and the auxiliary drive wheels with a drive-power distribution ratio between the auxiliary drive wheels and the main drive wheels, such that the drive-power distribution ratio is variable with an engaging force of the drive-power distribution clutch being controlled; and (d) a control apparatus configured, when determining that a heat load of the drive-power distribution clutch is large during deceleration running of the vehicle, to limit a regenerative torque of the rotating machine, as compared with when determining that the heat load is small.

The disclosure relates to a method for controlling a driveline (10) of a vehicle (1), wherein the driveline (10) at least comprises a transmission (13) and a clutch (12), wherein the clutch (12) is adapted to be provided between the transmission (13) and a propulsion unit (11) of the driveline (10), wherein the method comprises the steps of; predicting an imminent drive route, identifying if the imminent drive route comprises any clutch severity classification (CSC), and if the imminent drive route comprises a clutch severity classification (CSC)—estimating (103) an expected clutch temperature (Tic) dependent on at least the clutch severity classification (CSC) and one vehicle parameter (Vp), wherein, the clutch severity classification (CSC) is at least dependent on an inclination of the imminent drive route, and if (105) the expected clutch temperature (Tic) is above a clutch temperature threshold value (Tt); controlling (106) the driveline (10) in a critical heat mode, wherein in the critical heat mode the transmission (13) is controlled such that a clutch temperature increase is lower in comparison to a normal driveline control mode.

A temperature estimation device for friction engaging elements including an execution device and a storage device is provided. The storage device stores mapping data that defines mapping. The mapping includes, as an input variable, a heat amount variable that is a variable indicating an amount of heat generated by the friction engaging elements during the shifting of the transmission and a shifting variable indicating the friction engaging elements to be engaged at the time of the shifting of the transmission, and, as an output variable, the temperature. The execution device executes an acquisition process of acquiring a value of the input variable and a calculation process of inputting the value of the input variable acquired by the acquisition process into the mapping to calculate a value of the output variable.

The invention relates to a method for controlling a driveline (10) of a vehicle (1), wherein the driveline (10) at least comprise a clutch (12) and a transmission (13), where the clutch (12) is adapted to connect the transmission to an propulsion unit (11). The method comprises the steps of;—estimating (105) an upcoming clutch temperature at least dependent on an imminent drive route, and if (106) the estimated upcoming clutch temperature is above a threshold value (T);—controlling (107) the driveline (10) in a critical heat mode, wherein in the critical heat mode the transmission (13) is controlled such that a clutch temperature increase is lower in comparison to a normal driveline control mode.

A temperature estimation device for friction engaging elements including an execution device and a storage device is provided. The storage device stores mapping data that defines mapping. The mapping includes, as an input variable, a heat amount variable that is a variable indicating an amount of heat generated by the friction engaging elements during the shifting of the transmission and a shifting variable indicating the friction engaging elements to be engaged at the time of the shifting of the transmission, and, as an output variable, the temperature. The execution device executes an acquisition process of acquiring a value of the input variable and a calculation process of inputting the value of the input variable acquired by the acquisition process into the mapping to calculate a value of the output variable.