A drive system for a vehicle comprises two electrical machines arranged between a combustion engine and an input shaft to a gearbox. The first machine's rotor and the input shaft of the gearbox are each connected to a separate component of a planetary gear. The second electrical machine's rotor is connected with the output shaft of the combustion engine, which is connected with another component of the planetary gear. A first locking means may be moved between a locked position, in which the planetary gear's three components rotate at the same rotational speed, and a release position, allowing for different rotational speeds. A second locking means is moveable between a locked position, in which the output shaft of the combustion engine is locked together with the second machine's rotor and a release position, in which the combustion engine's output shaft is disconnected from the second machine's rotor.

In a method for controlling a vehicle with a drive system comprising a power unit configuration adapted to provide output for the vehicle's operation, and further comprising a planetary gear and a first and second electrical machine, connected to components in the planetary gear via their rotors, a locking means is moved from a locked position, in which two of the planetary gear's components are locked together, so that the three components of the planetary gear rotate with the same speed, to a release position, when the vehicle is driven with the locking means in a locked position, by carrying out the following method steps. The power unit configuration is controlled in order to achieve torque balance between the components that are locked together by the locking means, and such locking means are moved into a release position, when said torque balance prevails.

A control apparatus for a stepped automatic transmission in which one of a plurality of shift speeds is established by selectively engaging a plurality of frictional engagement elements, the stepped automatic transmission mounted on a vehicle, the control apparatus includes: an electronic control unit configured to perform a control of prohibiting a plurality of shift that is transitioning from an upshift speed change to a downshift speed change, for a predetermined period, when a downshift speed change requirement is requested by an occurrence of an accelerator depression operation during an inertia phase of the upshift speed change in a driven state of a vehicle.

A vehicle regenerative speed control device is provided that includes a controller which performs a regenerative speed control for downshifting a belt-type continuously variable transmission to the low gear ratio side and increasing a rotational speed of a transmission input shaft to which a motor generator is connected when there is a request for an increase in the regeneration amount while decelerating. The controller also imposes the limitation of staying within a Pri end command rotational speed change rate for the Pri end command rotational speed when performing a regenerative speed control for increasing the Pri end command rotational speed based on a braking operation in a brake switching region for switching from regenerative braking to hydraulic braking due to a decrease in vehicle speed.

In a method for controlling a vehicle with a drive system comprising an output shaft of a combustion engine and a planetary gear with a first and a second electrical machine, connected via their rotors to the components of the planetary gear, the combustion engine is started while the vehicle is driven by ensuring that the rotor of the second electrical machine is connected with the output shaft of the combustion engine, and controlling such electrical machine's rotational speed towards the combustion engine's idling speed, whereupon fuel injection into the combustion engine is carried out to start the latter.

A method for operating a vehicle drive-train having a continuously power-branched transmission with secondary coupling. In the open operating condition of reversing clutches of a reversing gear unit, torque applied in the area of a drive output can be supported by a range group in the area of a variator. In the event of a command to interrupt the power flow between a drive engine and the drive output, it is checked whether the vehicle is on an inclined surface and if the result of that inquiry is positive, the power flow between the drive engine and the transmission is interrupted at the latest when the rotational speed of the drive output is reduced to zero by opening the reversing clutches, while the active connection between the drive output and the variator is maintained by way of the range group.

The present invention relates to a Self-Governed Gear Box (SGGB) functions as an automatic gear box system suitable for any power drive ranging from electrical to mechanical. This is an optimally-performed gear box system, in terms of power loss. The assembly is compact and simple with no additional elements other than gears. For the same reason, it is highly economical, easy to assemble and easy to maintain, with an expected ideal performance. Such a dynamic task of an automatic gear box system is achieved by implementing an algorithm enabling to sense the additional load applied at the input end, created by diverting a small quantity of power from the output end. This is in effect of inducing an engine disturbance as under-drive, under sub-optimum output rpm-torque conditions. As the engine disturbance introduced for sub-optimum output rpm-torque condition is a continuous governance mechanism, the input to output speed ratio assumed also will be continues in a designed range. The engine starts from zero speed when this gear box system is coupled between an engine and a load. Thus it is a continuously variable transmission system.

An electronic control unit is configured to select one of a series mode, a series-parallel mode and a parallel mode as a running mode. A load level of a hybrid vehicle is set to a value that is high in the order of a load level at which the parallel mode is selected, a load level at which the series-parallel mode is selected, and a load level at which the series mode is selected. That is, the electronic control unit selects the series-parallel mode in an intermediate load region, selects the series mode in a low load region, and selects the parallel mode in a high load region.

In a method for controlling a vehicle with a drive system comprising an output shaft in a combustion engine, a planetary gear and a first and second electrical machine connected to the planetary gear, the turning off of the combustion engine is achieved when the vehicle is driven with the combustion engine running, and a transition to operation of the vehicle with the electrical machines is achieved by ensuring that the second electrical machine's rotor is connected with the combustion engine's output shaft, that injection of fuel into the combustion engine is interrupted and that the second electrical machines rotational speed is controlled towards and until a standstill, whereupon the combustion engine's output shaft is disconnected from the second electrical machine and the planetary gear.

A controller-implemented method of controlling a machine having a rotor coupled to an engine through a variable transmission is provided. The controller-implemented method may include receiving a desired rotor speed, determining an engine load of the engine, adjusting an engine speed of the engine based on the engine load and one or more predefined efficiency points, and adjusting a gear ratio of the variable transmission based on the engine speed and the desired rotor speed.