A frequency of a harmonic of a drive source frequency of a rotary drive source is defined as a harmonic frequency, a resonant frequency of a torque transmitting rotary body is defined as a rotary body resonant frequency, and a resonant frequency of an endless belt is defined as a belt resonant frequency. A control device of a vehicle controls the belt resonant frequency in a manner so as to suppress a triple overlapping state in which the drive source frequency or the harmonic frequency, the rotary body resonant frequency, and the belt resonant frequency coincide with or closely approximate each other.

The present disclosure relates to active vibration control of a hybrid electric vehicle. One form provides a method that may include setting up a period of fast Fourier transform (FFT) and performing FFT of an engine speed or a motor speed corresponding to the period of the FFT from a reference angle signal; setting up a reference spectrum; extracting vibration components to be removed based on information of the reference spectrum; selecting and adding a removal object frequency from the vibration of each frequency and performing inverse FFT; determining a basic amplitude ratio according to the engine speed and the engine load; determining an adjustable rate which decreases an anti-phase torque as a change amount of the engine speed is decreased; and performing active vibration control of each frequency based on the information of the basic amplitude ratio, the adjustable rate, and the engine torque.

The present disclosure relates to an apparatus and a method for active vibration control of a hybrid electric vehicle. Forms of the present disclosure may provide a method for active vibration control of a hybrid electric vehicle that may include detecting an engine speed or a motor speed; selecting a reference angle signal based on position information of a motor or an engine; setting up a period of fast Fourier transform (FFT) and performing FFT of the engine speed or the motor speed corresponding to the period of the FFT from the reference angle signal; setting up a reference spectrum according to an engine speed and an engine load; extracting a vibration components to be removed based on information of the reference spectrum; summing vibration components to be removed according to the frequencies and performing inverse FFT; determining an amplitude ratio according to the engine speed and the engine load; and performing active vibration control of each frequency based on the information of the amplitude ratio and the engine torque.

Provided is a method of controlling a hybrid electric vehicle capable of improving acceleration response upon kick-down. The method includes calculating a rising gradient of a motor speed increasing during kick-down shift based on a present speed of a motor for driving the vehicle which is detected at a control unit in real time, upon detection of demand of kick-down shift due to acceleration operation of a driver, calculating a falling gradient of intervention torque based on the rising gradient of the motor speed at the control unit, determining an entry point of intervention control based on the present speed of the motor detected at the control unit in real time, and performing torque intervention control for controlling driving of the motor in order to output intervention torque, namely, motor torque decreased based on the falling gradient of intervention torque calculated from the determined entry point at the control unit.

An apparatus for active vibration control of a hybrid electric vehicle including an engine and a motor is disclosed. The apparatus includes: a position sensor to detect position information of the engine or the motor; and a controller to select a reference angle signal based on a signal from the position sensor. The controller performs fast Fourier transform (FFT) analysis by generating a reference angle, extracts a vibration component of each frequency through the FFT analysis, generates a reference signal by performing inverse FFT, and performs active vibration control of each frequency by reflecting a basic amplitude ratio, an adjustable rate according to an engine load, and an engine torque to the reference signal.

A shift control system for vehicle that improves an acceleration feeling while suppressing a shift shock includes a controller that controls a transmission and a hydraulic controller. The controller, during an inertia phase where an input speed of the transmission changes toward a synchronous speed in a gear stage after a shift, sets an oil pressure of a specific frictional engagement device configuring the gear stage after the shift, of a plurality of frictional engagement devices to an oil pressure that, at a time of the shift, exceeds a first oil pressure to set a transmission torque capacity equal to a first drive torque applied to the specific frictional engagement device of a drive torque outputted from a prime mover, but is less than a second oil pressure to set a transmission torque capacity equal to a second drive torque which is the first drive torque to which has been added an inertia torque generated by inertia on a prime mover side accompanying a change in speed ratio.

The present disclosure relates to active vibration control of a hybrid electric vehicle. One form provides a method that may include setting up a period of fast Fourier transform (FFT) and performing FFT of an engine speed or a motor speed corresponding to the period of the FFT from a reference angle signal; setting up a reference spectrum; extracting vibration components to be removed based on information of the reference spectrum; selecting and adding a removal object frequency from the vibration of each frequency and performing inverse FFT; determining a basic amplitude ratio according to the engine speed and the engine load; determining an adjustable rate which decreases an anti-phase torque as a change amount of the engine speed is decreased; and performing active vibration control of each frequency based on the information of the basic amplitude ratio, the adjustable rate, and the engine torque.

The present disclosure relates to an apparatus and a method for active vibration control of a hybrid electric vehicle. Forms of the present disclosure may provide a method for active vibration control of a hybrid electric vehicle that may include detecting an engine speed or a motor speed; selecting a reference angle signal based on position information of a motor or an engine; setting up a period of fast Fourier transform (FFT) and performing FFT of the engine speed or the motor speed corresponding to the period of the FFT from the reference angle signal; setting up a reference spectrum according to an engine speed and an engine load; extracting a vibration components to be removed based on information of the reference spectrum; summing vibration components to be removed according to the frequencies and performing inverse FFT; determining an amplitude ratio according to the engine speed and the engine load; and performing active vibration control of each frequency based on the information of the amplitude ratio and the engine torque.

A method for active vibration control of a hybrid electric vehicle may include: selecting a reference angle signal based on position information of a motor or an engine; generating a reference angle based on information of the reference angle signal; setting up a period of fast Fourier transform (FFT) and analyzing the FFT signal; setting up a reference spectrum according to an engine speed and an engine load; extracting a vibration component from each frequency based on information of the reference spectrum; selecting and adding a removal object frequency from the vibration of each frequency and performing inverse FFT; determining a basic amplitude ratio according to the engine speed and the engine load and an adjustable rate according to the engine load; and performing active vibration control of each frequency based on the information of the basic amplitude ratio, the adjustable rate, and the engine torque.

A four-wheel drive vehicle is provided, including an engine with an operating mode that is switchable between all-cylinder and reduced-cylinder operating modes, a torque transmission assembly for transmitting an output torque of an engine to main drive wheels and auxiliary drive wheels, a torque ratio adjusting device included in the torque transmission assembly and configured to adjust a ratio of the output torque distributed to the auxiliary drive wheels, and controller that executes a noise suppression module for increasing the torque ratio provided to the auxiliary drive wheels by the torque ratio adjusting device so as to suppress noise generation at the torque transmission assembly, in the all-cylinder and reduced-cylinder operating modes. The noise suppression device changes the torque ratio provided to the auxiliary drive wheels according to engine operating ranges where the torque transmission assembly is in a noise generating state in the all-cylinder and reduced-cylinder operating modes, respectively.