A plurality of virtual gear positions are established by an electric continuously variable transmission, and the number of speeds of the virtual gear positions is equal to or larger than the number of speeds of mechanical gear positions of a mechanical stepwise variable transmission. One or two or more virtual gear positions is/are assigned to each mechanical gear position, and shifts among the mechanical gear positions are performed in the same timing as the shift timing of the virtual gear positions. Thus, shifting of the mechanical stepwise variable transmission is accompanied by change of the engine speed Ne, and the driver is less likely to feel uncomfortable even if shift shock occurs during shifting of the mechanical stepwise variable transmission.

A plurality of virtual gear positions are established by an electric continuously variable transmission, and the number of speeds of the virtual gear positions is equal to or larger than the number of speeds of mechanical gear positions of a mechanical stepwise variable transmission. One or two or more virtual gear positions is/are assigned to each mechanical gear position, and shifts among the mechanical gear positions are performed in the same timing as the shift timing of the virtual gear positions. Thus, shifting of the mechanical stepwise variable transmission is accompanied by change of the engine speed Ne, and the driver is less likely to feel uncomfortable even if shift shock occurs during shifting of the mechanical stepwise variable transmission.

A method is provided to control a hybrid powertrain comprising an internal combustion engine; a gearbox with input and output shafts; a range gearbox, connected to the output shaft; a first planetary gear, connected to the input shaft; a second planetary gear, connected to the first planetary gear; a first electrical machine, connected to the first planetary gear; a second electrical machine, connected to the second planetary gear; at least one gear pair, connected with the first planetary gear and the output shaft; and at least one gear pair, connected with the second planetary gear and the output shaft, wherein the internal combustion engine is connected with the first planetary gear via the input shaft. The method comprises the steps: a) engaging a gear by way of connecting two rotatable components in the first planetary gear; b) connecting the at least one gear pair, connected with the second planetary gear and the output shaft; c) connecting a sixth gear pair, arranged between a countershaft and the range gearbox with the countershaft, so that the countershaft is connected with the output shaft via the range gearbox; d) controlling the range gearbox from a low range position to a neutral state, in which no torque transmission occurs through the range gearbox; e) controlling two rotatable components in the range gearbox towards achieving a synchronized rotational speed with the assistance of the first electrical machine; f) connecting the rotatable components with the use of a shiftable third clutch device; and g) engaging a gear by way of connecting two rotatable components in the second planetary gear.

A method is provided to control a hybrid powertrain comprising an internal combustion engine; a gearbox with input and output shafts; a range gearbox, connected to the output shaft; a first planetary gear, connected to the input shaft; a second planetary gear, connected to the first planetary gear; a first electrical machine, connected to the first planetary gear; a second electrical machine, connected to the second planetary gear; at least one gear pair, connected with the first planetary gear and the output shaft; and at least one gear pair, connected with the second planetary gear and the output shaft, wherein the internal combustion engine is connected with the first planetary gear via the input shaft. The method comprises the steps: a) engaging a gear by way of connecting two rotatable components in the first planetary gear; b) connecting the at least one gear pair, connected with the second planetary gear and the output shaft; c) connecting a sixth gear pair, arranged between a countershaft and the range gearbox with the countershaft, so that the countershaft is connected with the output shaft via the range gearbox; d) controlling the range gearbox from a low range position to a neutral state, in which no torque transmission occurs through the range gearbox; e) controlling two rotatable components in the range gearbox towards achieving a synchronized rotational speed with the assistance of the first electrical machine; f) connecting the rotatable components with the use of a shiftable third clutch device; and g) engaging a gear by way of connecting two rotatable components in the second planetary gear.

An infinitely variable transmission (IVT) provides a plurality of transmission modes. At least one mode is a serial mode and at least one other mode is a split-path mode. The IVT provides substantially seamless shifting between the plurality of transmission modes.

A control system for a machine having a power source configured to provide power, a number of implements including a work implement, configured to provide operations, and a number of power transmitting paths configurable to selectively make power available to the implements to perform operations. The control system may include a control arrangement configured to regulate the power source to provide a first level of available power, to configure a first power transmitting path to make a percentage A1 of said first level of power available to provide a first operation, and to configure a second power transmitting path to make a percentage A2 of said first level of power available to provide a second operation, at least the second operation being a work operation. The control arrangement may further be configured to increase said first level of available power of said power source to a second level of available power, to configure the first power transmitting path to make a percentage B1 of said second level op power available to provide said first operation, and to configure the second power transmitting path to make a percentage B2 of said second level of power available to provide said second operation, such that the ratio B2/B1 is greater than the ratio A2/A1.

A control system for a machine having a power source configured to provide power, a number of implements including a work implement, configured to provide operations, and a number of power transmitting paths configurable to selectively make power available to the implements to perform operations. The control system may include a control arrangement configured to regulate the power source to provide a first level of available power, to configure a first power transmitting path to make a percentage A1 of said first level of power available to provide a first operation, and to configure a second power transmitting path to make a percentage A2 of said first level of power available to provide a second operation, at least the second operation being a work operation. The control arrangement may further be configured to increase said first level of available power of said power source to a second level of available power, to configure the first power transmitting path to make a percentage B1 of said second level op power available to provide said first operation, and to configure the second power transmitting path to make a percentage B2 of said second level of power available to provide said second operation, such that the ratio B2/B1 is greater than the ratio A2/A1.

A power transmission device includes an input shaft, an output shaft, a differential device, a continuously variable transmission unit, and a control device. The differential device includes a first rotation element connected to the input shaft, a second rotation element connected to the output shaft, and a third rotation element. The continuously variable transmission unit includes a conversion unit configured to convert rotational power of the third rotation element into an other power, and a reconversion unit configured to reconvert the converted other power into the rotational power and supply the reconverted rotational power to the output shaft. The control device includes a continuously variable transmission control unit configured to generate a control signal of the continuously variable transmission unit such that the other power generated by the conversion unit exceeds the other power input to the reconversion unit.

A vehicle includes an engine, a continuously variable transmission including an input shaft coupled to the engine, an output shaft, an electric machine, and a gearing arrangement. The electric machine is configured to actuate the gearing arrangement to change a speed ratio between the input and output shafts. A controller is programmed to, responsive to a request to manually shift the transmission to one of a predetermined number of virtual discrete speed ratios and the engine being OFF, command starting of the engine regardless of a driver-demand torque and operate the electric machine to shift the transmission to the one of the speed ratios.

When it is determined that there is a likelihood of occurrence of an abnormality in a supercharger, a maximum engine rotation speed and a maximum MG2 rotation speed are changed to a low rotation speed side and operating points of an engine and a rotary machine are controlled such that an engine rotation speed and an MG2 rotation speed are respectively within ranges which do not exceed the changed maximum rotation speeds. Accordingly, even when the supercharger does not operate normally and an abnormal increase in a supercharging pressure occurs, it is possible to curb a high-rotation state of the engine rotation speed and the MG2 rotation speed. As a result, even when an abnormal increase in the supercharging pressure occurs, it is possible to curb a decrease in durability of components.