A vehicle control method is provided for controlling a vehicle in which a clutch provided on a power transmission path between an engine and a drive wheel is disconnected when a shift range is a non-driving range and the clutch is connected when the shift range is a driving range. The vehicle control method controls the engine to a prescribed idling speed, controls engine torque to a negative torque by delaying an ignition timing of the engine; and causes the prescribed idling speed to drop within a prescribed amount of time needed for the clutch to switch from being disconnected to being connected when the shift range is switched from the non-driving range to the driving range.

During a fuel cut-off control, if a vehicle deceleration rate becomes greater than a rapid deceleration determination value, which is calculated based on a rotational resistance of internal combustion engine 1, a vehicle is determined to be in a state of rapid deceleration. The rapid deceleration determination value is set to decrease as the rotational resistance of internal combustion engine 1 increases. The rotational resistance thereof increases as the vehicle speed decreases, and increases as a transmission gear ratio increases. Thereby, during decelerating on a high vehicle speed side, an erroneous determination of rapid deceleration due to a longitudinal vibration of the vehicle that occurs when the fuel cut-off control starts can be prevented, and during decelerating on a low vehicle speed side, a determination of rapid deceleration can be implemented to terminate the fuel cut-off control and thereby prevent the internal combustion engine 1 from being stopped.

The present disclosure relates to an apparatus for extracting vibration of a hybrid vehicle, and more particularly, to an apparatus and a method of extracting vibration of a hybrid vehicle by varying a target vibration frequency. An apparatus for extracting vibration of a hybrid electric vehicle includes: an engine and a driving motor, which are power sources; a starter motor/generator connected to the engine; and a control unit configured to measure a motor speed of the starter motor/generator, to generate a speed variation quantity based on the motor speed of the starter motor/generator, to calculate a vibration frequency of the engine when the speed variation quantity exceeds a reference value, to set a filter band based on the vibration frequency of the engine, and to extract, with the filter band, a vibration of the engine.

Disclosed are a method of and an apparatus for controlling a vibration of a hybrid electric vehicle. An apparatus for controlling a vibration of a hybrid electric vehicle may include: an engine position detector detecting a position of an engine; an air amount detector detecting an air amount flowing into the engine; an accelerator pedal position detector detecting a position of an accelerator pedal; a vehicle speed detector detecting a speed of the hybrid electric vehicle; and a controller. The controller controls operation of a motor based on the position of the engine, the air amount, the position of the accelerator pedal, and the speed of the hybrid electric vehicle.

A hybrid vehicle with an engine and a rotary machine each coupled to a drive wheel in a power transmittable manner, comprises: an electronic control device that makes the rotary machine output a starting-time compensation torque to compensate a drop in a drive torque caused in a starting process of the engine in addition to a running torque when the engine is started while the vehicle is in a running state in which the drive torque is generated by the rotary machine and the engine is in a stopped state. The electronic control device starts the engine such that a starting-time inertia torque that is generated according to starting of the engine and causes the drop in the drive torque is made smaller when a torque margin of the rotary machine which is applied to the starting-time compensation torque is relatively small than when the torque margin is relatively large.

Powertrains may include a spring damper between the engine crankshaft and transmission input shaft. In some circumstances, an oscillation known as shuffle may occur in such powertrains. Active adjustment of engine torque is substantially more effective at mitigating shuffle oscillations if the engine torque includes a p-term proportional to displacement of the damper spring in addition to a d-term proportional to the speed difference across the damper. For various reasons, the spring displacement is difficult to measure directly. An observer algorithm is utilized to calculate a current estimated spring displacement based on a crankshaft speed sensor, a transmission input speed sensor, a wheel speed sensor, and past engine torques, using a dynamic model of the powertrain.

A drive system of a hybrid vehicle including an internal combustion engine, a first motor-generator, a power transmission path, a power division mechanism, a second motor-generator, a one-way clutch, a mode change mechanism, and an electronic control unit having a microprocessor and memory. The microprocessor is configured to control the first motor-generator so as to reduce a reaction force acting on the first motor-generator at a time at which a state of the one-way clutch changes from an unlocked state to a locked state, when a drive mode is changed from an EV mode to a HV mode through a start mode by the mode change mechanism.

Methods and systems are provided for starting an engine in a hybrid vehicle. In one example, a method includes cranking an engine of the vehicle by controlling a capacity of a clutch of a dual clutch transmission positioned downstream of the engine and compensating for driveline disturbance resulting from the cranking via controlling an electric machine positioned downstream of the dual clutch transmission. In this way, engine starting may be conducted under a variety of vehicle operating conditions.

An electric vehicle includes a second rotating electric machine; a first transmission path configured to transmit force generated by the second rotating electric machine to a wheel; a first clutch that is arranged in the first transmission path and configured to switch between a connected state and a disconnected state between the second rotating electric machine and the wheel; and an ECU configured to control the second rotating electric machine and the first clutch. In the electric vehicle, a torque sensor is arranged between the first clutch and the wheel in the first transmission path.

A variety of methods and arrangements for mitigating powertrain and accessory torsional oscillation through electric motor/generator control are described. In one aspect, working chamber air charge and crank position are determined prior to starting an engine. During the engine startup period, an electric motor/generator supplies a smoothing torque to at least partially cancel engine torque variations.