Abstract: An electrically-variable transmission is provided with first and second motor/generators and three planetary gear sets. The planetary gear sets have continuous interconnections, and selective connections via a plurality of torque-transmitting mechanisms, that provide three forward electrically-variable modes. Preferably, the planetary gear sets are characterized by effective gear ratios such that a substantially equal maximum torque is required from each of the motor/generators during the three forward electrically-variable modes for a given torque on the input member. This allows the first and second motor/generators to be substantially equal in size.

Abstract: A single range, electrically variable transmission (EVT) is provided with a lockup clutch that reduces motor power requirements. When applied, the lockup clutch allows engine torque to be transmitted directly to the output without the necessity of a motor/generator supplying reaction torque. With the lockup clutch applied, the transmission operates with zero electro-mechanical power flow at a fixed mechanical ratio, thus mitigating the power peak which occurs through the motor/generators. Input-split, output-split, and compound-split transmissions are disclosed. A method of operating an EVT with a lockup clutch is also provided.

Abstract: An electrically-variable transmission having two differential gear sets and two motor/generators uses four torque-transmitting mechanisms and selective as well as continuous connecting members and preferably provides an input-split operating mode and an output-split operating mode.

Abstract: A torque-transmitting assembly is provided that includes a dog clutch isolated by a device such as a rotary hydrostatic damper from relative loading on the torque input member and torque output member that it is to connect for common rotation and torque transmission. Although its use is not limited to electrically-variable transmissions, the torque transmitting assembly is able to function even with the large inertia and potentially random torque inputs associated with theses types of transmissions.

Abstract: There is provided a transmission device having an electrically variable output that employs three electrically powered motor-generators, or machines. The electrically-variable transmission device comprises first, second and third electrical machines coaxial to and coupled to a plurality of planetary gear sets. Each planetary gear set coupled to a main shaft operative to transmit torque therebetween and operative to transmit torque to an output. There is an input mechanically coupled to one of the planetary gear sets. This transmission device can transmit mechanical power with a continuously variable ratio of the input shaft speed to the output shaft speed using two of the electric motors at a time, forming an input-split or either an output-split or a compound-split. A selectively actuable brake device is operative to multiply torque output from the second electrical machine.

Abstract: Methods are provided for manufacturing a magnetizable core component for use in an electric motor. The method includes forming a green body from a powdered metal-ceramic composite. The method also includes heating the green body to form a core. The method further includes applying a magnetic field to the core to produce paths in a predetermined orientation, where the paths are configured to allow flux to flow therealong. The magnetizable core component is also provided.

Abstract: A hybrid powertrain includes a hybrid transmission having an engine input and two motor/generator units, which are interconnected by a planetary gear mechanism and three selectively engageable torque-transmitting mechanisms to establish three modes of transmission operation including an input split mode, a first compound split mode, and a second compound split mode.

Abstract: The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including first, second and third differential gear sets, a battery, two electric machines serving interchangeably as motors or generators and five or six selectable torque-transfer devices. The selectable torque transfer devices are engaged to provide an EVT with a continuously variable range of speeds (including reverse), four or more mechanically fixed forward speed ratios and at least one mechanical reverse speed ratio. The torque transfer devices and the first and second motor/generators are operable to provide six operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, fixed forward mode and mechanical reverse mode.

Abstract: A vehicle powertrain for a hybrid vehicle includes an electronically variable transmission (EVT) with an input member to receive mechanical rotary power from the engine, an output member to provide mechanical rotary power to a vehicle powertrain to propel the vehicle, and an EVT gear train configured to selectively and operatively couple the input member to the output member. The EVT further includes first and second motor/generators driveably coupled to the gear train. A selectively engageable input brake mechanism is provided to create a reaction torque for the motor/generators thereby enabling the motor/generators to be used with additive power for electric propulsion or regenerative braking. The input brake improves electrical power to mechanical power conversion efficiency by reducing power circulation when the EVT is operated in electric drive, engine off mode.

Abstract: A hybrid powertrain system for a vehicle includes an engine and a transmission. The transmission includes a transmission input member, first and second electric machines, first and second planetary gear sets, and a plurality of selectively engageable torque transfer devices enabling configuring the powertrain in variously to operate in electric drive, electrically variable, fixed gear and neutral charging operating states.

Abstract: A vehicle has a powertrain including an engine and at least one electric machine. A method for maximizing range capability of the vehicle while operating in an electric vehicle operating state includes determining an incipient electric vehicle operating state of the powertrain, setting a preferred charge/discharge rate of an electric energy storage device to a maximum charging rate, and controlling the powertrain to an operating state including an engine state that is ON to effect charging the electrical energy storage device based on the maximum charging rate.

Abstract: The present invention provides an accessory drive system for a hybrid vehicle. The accessory drive system includes an inverter operatively connected to a direct current battery. The inverter is configured to convert the direct current from the battery into three-phase alternating current. The accessory drive system also includes a transmission having a first motor/generator operable to drive the hybrid vehicle. The first motor/generator is a Y-connected three phase motor/generator that defines a first neutral point. A second motor/generator is connected to an accessory and to the first neutral point. Output from the battery is transferable through the first neutral point to the second motor/generator such that the accessory is driven at a selectable rate.

Abstract: An electrically variable transmission having two motor/generators provides power-split, electrically variable power flow along dual power paths and provides multiple operating modes, including an electrically variable input-split mode. The transmission also includes a differential gear set having five gear elements. A first of the motor/generators is continuously connected to one of the gear elements and a second of the motor/generators is separately selectively connectable to two of the other gear elements. When the second motor/generator is connected to both of the gear elements, a fixed speed ratio can be established; thus, no lock-up clutch is necessary to achieve a fixed speed ratio through the differential gear set.

Abstract: The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including first, second and third differential gear sets, a battery, two electric machines serving interchangeably as motors or generators and four selectable torque-transfer devices. The selectable torque transmitting devices are engaged to yield an EVT with a continuously variable range of speeds (including reverse) and four mechanically fixed forward speed ratios. The torque transmitting devices and the first and second motor/generators are operable to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode.

Abstract: An electrically variable transmission having a single motor/generator provides electrically variable power flow along dual power paths and provides an electrically variable reverse operating mode. The transmission includes a compound differential gear set having at least four gear elements operatively interconnected with one another. A transmission input member and the single motor/generator selectively provide power to a transmission output member via the differential gear set. The transmission includes a plurality of intermeshing gears, including a reversing gear and gears connected for rotation with the output member, for operatively connecting the differential gear set with the output member. Torque-transmitting mechanisms are selectively engagable to provide power flow between the input member and the output member in multiple operating modes, including a parallel hybrid electrically variable reverse operating mode utilizing the reversing gear.

Abstract: An electrically variable transmission has a differential gear set with first, second and third members operatively connected between an input member and an output member. The input member is also operatively connected to an engine for receiving power from the engine. The transmission also includes a compound motor/generator that has a single stator and at least two rotors, referred to herein as first and second rotors. The single stator is operable to provide power to, receive power from and transfer power between the two rotors. The rotors are each operatively connected to a different respective member of the differential gear set. The transmission has a mechanical power path and an electromechanical power path. In some embodiments, selectively engagable torque-transmitting mechanisms are positioned to allow various modes of electrically variable power flow. Input-split and compound-split embodiments are presented.

Abstract: A transmission device for a powertrain system comprising a compound planetary gear set having four coaxial elements and a plurality of input nodes and an output node is described. The first input node is connected to an input shaft from an engine. The second input node is connected to a shaft of a first electrical machine. A plurality of input nodes are selectively connectable to a second electrical machine. The output node of the transmission device is connected to an output shaft of the transmission.

Abstract: The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including three or four differential gear sets, a battery, two electric machines serving interchangeably as motors or generators, seven or eight selectable torque-transfer devices and possibly a dog clutch. The selectable torque transmitting devices are engaged to yield an EVT with a continuously variable range of speeds (including reverse) and up to six mechanically fixed forward speed ratios. The torque transmitting devices and the first and second motor/generators are operable to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode.

Abstract: The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including first, second and third (and possibly fourth) differential gear sets, a battery, two electric machines serving interchangeably as motors or generators, five, six or seven selectable torque-transfer devices and possibly a dog clutch. The selectable torque transmitting devices are engaged to yield an EVT with a continuously variable range of speeds (including reverse) and up to six mechanically fixed forward speed ratios. The torque transmitting devices and the first and second motor/generators are operable to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode.

Abstract: The electrically variable transmission family of the present invention provides low-content, low-cost electrically variable transmission mechanisms including first and second differential gear sets, a battery, two electric machines serving interchangeably as motors or generators, up to six selectable torque-transfer devices and possibly a dog clutch. The selectable torque transmitting devices are engaged to yield an EVT with a continuously variable range of speeds (including reverse) and at least four mechanically fixed forward speed ratios. The torque transmitting devices and the first and second motor/generators are operable to provide five operating modes in the electrically variable transmission, including battery reverse mode, EVT reverse mode, reverse and forward launch modes, continuously variable transmission range mode, and fixed ratio mode.