Method and apparatus of controlling vibration of hybrid electric vehicle

A method of controlling a vibration of a hybrid electric vehicle, the method comprising:

• calculating a motor speed based on a position of a motor;
• setting a reference angle based on the position of the motor;
• setting a window for performing Walsh-based Discrete Fourier Transform (WDFT) based on the reference angle;
• calculating a magnitude spectrum and a phase spectrum by performing the WDFT based on the motor speed, the reference angle, and the window;
• selecting a control target frequency based on the magnitude spectrum;
• compensating a magnitude of the control target frequency by applying a scale factor to the control target frequency;
• generating a reference signal by performing Inverse Walsh-based Discrete Fourier Transform (IWDFT) based on the magnitude and a phase of the control target frequency;
• determining a magnitude ratio of the reference signal based on an engine speed and an engine load;
• calculating a command torque by applying the magnitude ratio and an engine torque to the reference signal;
• calculating an inverse phase torque of the command torque;
• determining whether to generate the inverse phase torque based on the engine speed;
• and
• controlling operation of the motor to generate the inverse phase torque when the engine speed is less than a predetermined speed.