A shift control system and a shift control method configured to execute a skip shift smoothly are provided. The shift control system selects an interim gear stage with reference to a control map. The control map is configured to determine: an intense region where a driver is allowed to sense an increase in the acceleration sufficiently based on an unconscious period, and a stimulation intensity; and a moderate region where acceleration is increased in a mild manner. During execution of the skip shift, the acceleration is increased in a mild manner by shifting the gear stage from an initial stage to the interim gear stage, and then increased significantly by shifting the gear stage from the interim gear stage to a target gear stage.

A method is provided to control a hybrid powertrain comprising engaging gears corresponding to a first gear pair connected with a first planetary gear in a gearbox with a first coupling device connecting two rotatable components in the first planetary gear; activating a second electrical machine to generate a propulsion torque on the output shaft via a second gear pair connected with a second planetary gear and the output shaft; disconnecting the first gear pair from the countershaft, by controlling the first electrical machine and a combustion engine connected with the first planetary gear to achieve a substantially zero torque state between the first gear pair; connecting the first gear pair to the countershaft, by controlling the combustion engine to achieve a synchronous rotational speed between the first gear pair; and activating the combustion engine and/or the first electrical machine to generate a propulsion torque on the output shaft.

A multi-speed automatic vehicle transmission has an electronic control unit which permits multiple downshifts if certain conditions are satisfied. Such downshifts are direct and omit engagement and disengagement of one or more intermediate speed ratios. Multiple downshifting may allow the actual speed ratio to better match the ideal speed ratio, for example under heavy braking.

A control device for an automatic transmission is provided. The automatic transmission is configured to realize a plurality of gear shift stages by combination of a plurality of engaging devices engaged or released among the plurality of engaging devices. The control device includes an electronic control unit. The electronic control unit is configured to select, as the setting pattern realizing an intermediate gear shift stage, the setting pattern with a smaller number of switching of the engagement or release of the engaging device than the number of switching of the setting pattern with the largest number of switching among the plurality of setting patterns when a shift is performed from a first gear shift stage to a second gear shift stage through the intermediate gear shift stage in a case where the electronic control unit determines that the shift is to be performed through the intermediate gear shift stage.

A motor vehicle having a drive unit, the power output shaft of which outputs alternately to a first sub-transmission or a second sub-transmission of a dual clutch transmission by way of two separating clutches of a dual clutch. The first sub-transmission has the odd-numbered forward gears and the second sub-transmission has the even-numbered forward gears, and having a transmission control device, which has a driving strategy unit for determining a target gear as a function of input parameters and a shift sequence control unit, with which a gear change from the current gear to the target gear can be controlled.

When there is a request for a skip downshift that transitionally establishes an intermediate speed position, a surge hydraulic pressure at the start of a torque phase during shift control toward the intermediate speed position is set so as to be lower than a surge hydraulic pressure at the start of a torque phase during shift control toward a required speed position.

A jump shift of an automatic transmission with multiple shift speeds such as, e.g., ten forward speeds involves operation of many engagement elements. The shifting operation for the jump shift is therefore complicated, making it difficult for the automatic transmission to respond quickly. After shifting to the seventh speed as a direct coupling speed is completed by engaging three clutches C1, C3, C4, the remaining other clutch C2 is also engaged at the seventh speed. In the case of a jump shift, e.g., a shift from the seventh speed to the fifth speed, shifting to the fifth speed is completed by disengaging the clutch C1 and performing control to disengage the clutch C3 and to engage a brake B1 with the remaining other clutch C2 kept in the engaged state. This facilitates the shifting operation from the direct coupling speed and allows the automatic transmission to respond quickly.

In a controller for an automatic transmission, when a jump gear shift via a plurality of intermediate shift stages is executed, a first and a second target intermediate shift stages are extracted, and a target input shaft rotation speed change rate is calculated from a difference in synchronous rotation speed between a shift stage before a current gear shift and the second target intermediate shift stage as a target shift stage of a gear shift which is executed after the current gear shift. Accordingly, it is possible to avoid a situation in which a shifting time in the gear shift control of the step before the second target intermediate shift stage becomes very short and thus packing of a clutch pack is not executed in a timely manner.

When a jump downshift via an intermediate shift stage is requested and a rotation speed of an input shaft approaches a synchronous rotation speed of the intermediate shift stage, a target torque phase time when the gear shift via the intermediate shift stage is performed with input switching is set to be shorter than that when the gear shift via the intermediate shift stage is performed without using input switching and torque phase control is performed. Accordingly, it is possible to promptly perform engagement of an engagement-side frictional engagement element at the time of passing through the intermediate shift stage and to rapidly perform the gear shift after passing through the intermediate shift stage.

Methods and systems are provided for performing a multiple gear downshift of a transmission gear by transiently operating in an intermediate gear. In response to ambient humidity and a condensate level in a charge air cooler, the transmission gear may be downshifted from a higher gear to an intermediate gear, and then to a requested lower gear. Downshifting through an intermediate gear may also be controlled based on the gear shift request.