Abstract: A method of executing an electric-only (EV) mode transition in a vehicle includes determining vehicle operating values using a control system, processing the values to identify the transition, and executing the transition to or from the first or second EV mode. The transition is executed by selectively engaging and disengaging the input brake to zero, and by using the first and/or second traction motor to synchronize slip across the input brake. When the transition is from the first to the second EV mode or vice versa, the control system may use multiple speed and torque control phases to enter multiple intermediate modes, e.g., a pair of engine-on electrically-variable transmission modes and a fixed gear mode. A vehicle includes an engine, an input brake, first and second traction motors, and a transmission driven via the motors in a first and second EV mode. The vehicle includes the control system noted above.

Abstract: A hybrid control system for a hybrid electric vehicle (HEV) includes a hybrid control module. The hybrid control module includes a first motor control module that controls output torque of a first motor. A second motor control module controls output torque of a second motor based on a second motor torque request signal. The second motor torque request signal is generated based on a transmission output torque request signal prior to startup of an engine of the HEV. An override module generates a torque override request signal during the startup. The first motor control module controls output torque of the first motor to crank the engine during the startup. The second motor control module adjusts output torque of the second motor based on the torque override request signal and not the transmission output torque request signal during the startup to minimize vehicle jerk during the engine start.

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: An electrically-variable transmission is provided with first and second motor/generators and three planetary gear assemblies. At least one of the planetary gear assemblies is a planetary gear assembly having multiple planetary gear sets. As a result, the gears for the planetary gear assembly can be represented on multiple radial planes. Each of the planetary gear assemblies has continuous interconnections, and selective connections via a plurality of torque-transmitting mechanisms, that provide three forward electrically-variable modes. Preferably, the planetary gear assemblies are connected to one another in such a manner as to allow shifting between one of the electrically-variable modes to occur at a point offset from a mechanical power flow of the transmission. This decreases the maximum power output required from the motor/generators.

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 method is provided for transitioning from an initial to a final transmission mode in an electrically variable transmission (EVT), and includes transitioning to an intermediate mode having an additional speed degree of freedom (DOF), changing a transmission ratio, and engaging a clutch to shift to the final mode. The modes include input and compound split, fixed gear ratio, and electric torque converter (ETC), with and without input from an engine. Output torque is maintained by adjusting a charge on an energy storage device. A brake grounds an input member of the EVT. The EVT has the input member, an output member, a stationary member, and first and second motor/generators. An algorithm transitions between modes by releasing at least one clutch to transition to a mode having an extra speed degree of freedom (DOF), and utilizing the extra speed DOF to change the ratio of the EVT.

Abstract: A method minimizes driveline disturbances in a vehicle having a motor generator unit (MGU) and a controller, which may be a motor control processor or a hybrid control processor. The method includes determining a set of motor values of the MGU, including a change in motor speed, a derivative of the change in motor speed, and a motor jerk value; calculating a corrective final torque value for the MGU as a function of the set of motor values; and commanding the corrective final torque value from the MGU during a predetermined event, e.g., engine restart. Calculations and commanding the corrective final torque value are conducted by the controller within a calibrated minimum processing loop time. A vehicle includes first and second MGUs, and a controller electrically connected to the second MGU. The controller has the algorithm for minimizing driveline disturbances as noted above.

Abstract: A hybrid transmission that is operatively connected with an engine includes an input member operatively connected with the engine, at least one intermediate member, and an output member. A plurality of selectively engagable torque-transmitting mechanisms enable the input member to be selectively operatively connected to the at least one intermediate member through the first gearing arrangement by engagement of different ones of a first set of the torque-transmitting mechanisms. A single motor/generator is operatively connectable to the at least one intermediate member and is selectively operatively connected to the output member in two alternative ways through the second gearing arrangement by selective engagement of two respective ones of a second set of the torque-transmitting mechanisms to establish two different torque ratios between the at least one intermediate member and the output member.

Abstract: A transmission is provided with a reverse input split mode and, preferably, a reverse low fixed speed ratio which provides sufficient reverse grade performance while allowing motor size and planetary and transmission ratios to be optimized for fuel economy or other design criteria. Engine-on reverse performance is improved, reducing dependence on the battery and electric motors to meet reverse grade performance requirements.

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 transmission is provided with a reverse input split mode and, preferably, a reverse low fixed speed ratio which provides sufficient reverse grade performance while allowing motor size and planetary and transmission ratios to be optimized for fuel economy or other design criteria. Engine-on reverse performance is improved, reducing dependence on the battery and electric motors to meet reverse grade performance requirements.

Abstract: An electrically variable transmission (EVT) is provided with input member and output member, first and second motor/generators, a first and a second planetary gear set, and a final drive gearset. Two torque-transmitting mechanisms that are selectively engagable alone or in different combinations to establish an electric-only operating mode, an input split mode, a compound split mode, and a neutral mode. The first torque-transmitting mechanism may be configured as a one-way clutch in parallel with a friction clutch or a dog clutch, or configured as a lockable one-way clutch. A vehicle having the EVT may be driven electrically using one or both motor/generators, up to a maximum speed of the motor/generators. There are no slipping clutches when operated in an electric-only operating mode, and the engine provides most of the power for high-speed cruising. The EVT can transition from input split mode to compound split mode by synchronous shift.

Abstract: An electrically-variable transmission is provided with input member and output member, first and second motor/generators, a first planetary gear set and a final drive gearset. Two or three torque-transmitting mechanisms that are selectively engagable alone or in different combinations to establish at least one forward electric-only operating mode including a series mode, an output split mode, and at least one neutral mode including a purely neutral mode and a neutral battery charge mode. The transmission optionally includes a one-way clutch selected from the group of friction clutch and dog clutch, or is a lockable one-way clutch, for enabling low loss forward operation, regenerative braking functionality, and/or reverse vehicle operation.

Abstract: An electrically-variable transmission for use with an engine includes an input member configured for operative interconnection with the engine, an output member, and a stationary member. First and second motor/generators, a first and a second planetary gear set each having respective first, second, and third members are included. A first, a second, and a third selectively engagable torque-transmitting mechanism are included. The input member is connectable for common rotation with the first member of the first planetary gear set either continuously or selectively by engagement of the third torque-transmitting mechanism. The output member is connected for common rotation with the first member of the second planetary gear set. The motor/generators are controllable and the torque-transmitting mechanisms are selectively engagable to establish at least one electric-only mode, a series mode, an output-split mode, and at least one neutral mode.

Abstract: A multi-mode, electrically variable, hybrid transmission and improved shift control methods for controlling the same are provided herein. The hybrid transmission configuration and shift control methodology presented herein allow for shifting between different EVT modes when the engine is off, while maintaining propulsion capability and minimum time delay for engine autostart. The shift control maneuver is able to maintain zero engine speed while producing continuous output torque throughout the shift by eliminating transition through a fixed gear mode or neutral state. Optional oncoming clutch pre-fill strategies and mid-point abort logic minimize the time to complete shift, and reduce the engine start delay if an intermittent autostart operation is initiated.

Abstract: A powertrain is provided that includes an engine as well as a transmission having an input member and an output member. The powertrain also includes a motor/generator that has an energizable stator, a first rotor and a second rotor (i.e., a dual rotor motor). Both of the rotors are rotatable via energization of the stator. A first torque-transmitting mechanism, referred to as the engine clutch, is selectively engagable to connect the engine for common rotation with one of the first and the second rotors. A second torque-transmitting mechanism, referred to as the motor clutch, is selectively engagable to connect the first rotor for common rotation with the second rotor. The transmission input member is continuously connected for common rotation with the other of the first and second rotors.

Abstract: An electrically-variable transmission is provided with input member and output member, first and second motor/generators, a first planetary gear set and multiple additional planetary gear sets as well as at least four torque-transmitting mechanisms that are selectively engagable alone or in different combinations to establish a reverse electrically-variable operating mode, at least three forward electrically-variable operating modes, including two low range forward electrically-variable modes and a high range forward electrically-variable mode.

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: An apparatus includes a multi-phase inverter, a fault detector to indicate a detection of a fault, a sensor to provide a speed signal indicative of whether a speed of a PM motor is greater than a transition speed, and a controller. The controller is operable to apply either an open-circuit response or a short-circuit response to the multi-phase inverter. The open-circuit response is applied when the speed of the PM motor is greater less than the transition speed and a fault is detected. The short-circuit response is applied when the speed of the PM motor is less greater than the transition speed and the fault is detected. The transition speed is either a fixed predetermined speed or an adjusted predetermined speed.