Systems and methods for starting an engine of a hybrid vehicle are described. In one example, the method selects one or more electric machines to start an engine. The method may reference a data structure, such as a matrix or table, and the matrix or table outputs which of the one or more electric machines is applied to start the engine.

A hybrid power transmission mechanism includes an engine; a motor/generator having a rotor and a stator; a driven machine; a planetary gear mechanism having a sun gear, an internal gear drivingly connected to the rotor, a planetary gear, and a planetary carrier shaft including first and second extension shaft parts extending from the planetary gear in opposite directions; a first clutch switchable between a state of allowing transmission of power between the first shaft and the internal gear and a state of not allowing transmission of power therebetween; and a second clutch switchable between a state of allowing rotation of the sun gear and a state of not allowing rotation thereof. A first shaft that outputs power of the engine and a second shaft that inputs power to the driven machine are drivingly connected to the first and second extension shaft parts of the planetary carrier shaft, respectively.

Aspects of the present invention relate to a method and to a control system for controlling an engine and an electric traction motor of a vehicle, the control system comprising one or more controllers, wherein the control system is configured to: receive an indication of engine speed during engine idling; and control the electric traction motor to reduce a difference between the engine speed and an engine idle speed target

Systems and methods for starting an engine that may be started via an electric machine and a driveline disconnect clutch are described. In one example, the method estimates a maximum motor propulsive torque during engine starting. The maximum motor propulsive torque may be based on an estimated speed that a torque converter impeller speed will be when an engine cranking period ends.

An apparatus for controlling engine idling of a hybrid electric vehicle having an engine, an electric motor and a driving motor includes: an engine target speed determination part to determine an engine target speed when an engine idle speed control is requested; an engine target torque determination part to determine an engine target torque when the engine idle speed control is requested; a speed control part to determine a control torque for maintaining an engine speed at a predetermined speed based on a difference value between the engine target speed and an engine actual speed; a power split part to determine an output torque of the electric motor and an engine compensation torque of the engine based the control torque; and a final engine torque determination part to sum the engine compensation torque and the engine target torque to determine a final engine torque.

A transmission system is that includes a multi-speed gearbox. The multi-speed gearbox, in one example, includes a dual-clutch assembly configured to selectively engage a primary shaft and/or a second primary shaft and an electric drive clutch configured to selectively engage an electric drive interface gear, wherein the electric drive interface gear is positioned axially between two gears on the first or second primary shafts. The transmission system further includes a controller including instructions that when executed, during a first operating condition, cause the controller to operate the dual-clutch assembly to transfer mechanical power between an internal combustion engine (ICE) and the first primary shaft or the second primary shaft or operate the electric drive clutch to transfer mechanical power between an electric machine and the first primary shaft, the second primary shaft, or a secondary shaft.

A hybrid electric vehicle and method of its control include a parallel hybrid powertrain including an engine, a transmission, a battery system, a first electric motor coupled to the engine by a first clutch between the engine and the first electric motor, a second electric motor coupled to the transmission and to the first electric motor by a second clutch between the first and second electric motors, and a controller configured to control the parallel hybrid powertrain for optimal operation across a plurality of different propulsion and charging modes, including calculating cost values for each of the engine and the first and second electric motors and selecting optimal propulsion and charging modes based on the calculated cost values.

Systems and techniques for engine starter control may include determining a current speed band associated with an engine start for a current time increment, determining a previous speed band associated with the engine start for a previous time increment within the engine start, receiving a measured current value, determining a target current value based on the current speed band, the previous speed band, whether an acceleration or deceleration occurred between the current speed band and the previous speed band, and a mode of a system for engine starter control, and adjusting a current for the engine start based on the target current value.

A vehicle includes an engine including a crank shaft; a battery; a belt-integrated starter generator (BISG) mechanically coupled to the crank shaft and configured to generate electric power from motion of the engine to charge the battery; and a controller configured to operate the BISG to apply a load to the crank shaft to slow the engine and capture electric power for storage in the battery, wherein an initial magnitude of the load is proportional to a temperature of the engine, responsive to a speed of the BISG or engine achieving a predetermined non-zero threshold, remove the load from the crank shaft, and bring the engine to a stop.

An engine starting system for a gas turbine engine is provided. The engine starting system comprising: a gas turbine engine including rotational components comprising an engine compressor, an engine turbine, and a rotor shaft operably connecting the engine turbine to the engine compressor, wherein each rotational component is configured to rotate when any one of the rotational components is rotated; a permanent magnet alternator operably connected to at least one of the rotational components, the permanent magnet alternator being configured to rotate the rotational components; and a motor controller in electronic communication with the permanent magnet alternator, the motor controller being configured to command the permanent magnet alternator to rotate the rotational components at a selected angular velocity for a selected period of time.