Apparatus and method for outputting sound of vehicle

1. A sound output apparatus of an electric vehicle, the apparatus comprising:

a sensor configured to sense a driving speed of the electric vehicle and a number of revolutions of a driving motor of the electric vehicle;

a storage configured to store opposed-phase sound sources of a noise according to the number of revolutions of the driving motor of the electric vehicle; and

a controller configured to allow an opposed-phase sound source corresponding to the number of revolutions of the driving motor of the electric vehicle, from among the opposed-phase sound sources stored in the storage, to be output when the driving speed of the electric vehicle exceeds a predetermined speed to reduce the noise according to the number of revolutions of the driving motor of the electric vehicle;

wherein the noise includes a noise of the driving motor, a noise of a decelerator, and a noise of an inverter that are generated as the driving motor rotates;

wherein the controller is configured to obtain separately the noise of the driving motor, the noise of a decelerator, and the noise of the inverter according to the number of revolutions of the driving motor of the electric vehicle; and

wherein the controller obtains each frequency information of the noise of the driving motor, the noise of the decelerator, and the noise of the inverter by performing Fast Fourier Transform (FFT) on the noise of the driving motor, the noise of the decelerator, and the noise of the inverter obtained separately according to the number of revolutions of the driving motor of the electric vehicle.

2. The apparatus of claim 1 , wherein the controller tracks a noise of a specific order to be reduced based on the frequency information of the noise depending on the number of revolutions of the driving motor.

3. The apparatus of claim 2 , wherein the order indicates a number of events each of which causes a noise per unit rotation of the driving motor.

4. The apparatus of claim 2 , wherein the controller converts the noise of the specific order tracked depending on the number of revolutions of the driving motor into time data.

5. The apparatus of claim 4 , wherein the controller generates an opposed-phase sound source of the noise of the specific order to be converted into the time data and controls the storage to store the time data.

6. The apparatus of claim 1 , wherein the controller obtains and stores the opposed-phase sound source that is pre-generated in response to a predetermined accumulated distance driven.

7. The apparatus of claim 6 , wherein the controller updates the opposed-phase sound sources stored in the storage as the pre-generated opposed-phase sound source depending on an accumulated distance driven when the accumulated distance driven of the electric vehicle is the predetermined accumulated distance driven.

8. A method of outputting a sound of an electric vehicle, the method comprising:

storing, by a storage, opposed-phase sound sources of a noise according to a number of revolutions of a driving motor of the electric vehicle;

sensing, by a sensor, a driving speed of the electric vehicle and the number of revolutions of the driving motor when the driving speed of the electric vehicle exceeds a predetermined speed; and

outputting, by a controller, an opposed-phase sound source corresponding to the sensed number of revolutions of the driving motor among the stored opposed-phase sound sources to reduce the noise according the number of revolutions of the driving motor of the electric vehicle;

wherein the noise includes a noise of the driving motor, a noise of a decelerator, and a noise of an inverter that are generated as the driving motor rotates;

wherein the controller is configured to obtain separately the noise of the driving motor, the noise of a decelerator, and the noise of the inverter according to the number of revolutions of the driving motor of the electric vehicle;

obtaining each frequency information of the noise of the driving motor, the noise of the decelerator, and the noise of the inverter by performing Fast Fourier Transform (FFT) on the noise of the driving motor, the noise of the decelerator, and the noise of the inverter obtained separately according to the number of revolutions of the driving motor of the electric vehicle.

9. The method of claim 8 , wherein the storing of the opposed-phase sound sources further includes:

tracking a noise of a specific order to be reduced based on the frequency information of the noise depending on the number of revolutions of the driving motor.

10. The method of claim 9 , wherein the order indicates a number of events each of which causes a noise per unit rotation of the driving motor.

11. The method of claim 9 , wherein the storing of the opposed-phase sound sources further includes:

converting the noise of the specific order tracked depending on the number of revolutions of the driving motor into time data.

12. The method of claim 11 , wherein the storing of the opposed-phase sound sources includes:

generating an opposed-phase sound source of the noise of the specific order to be converted into the time data.

13. The method of claim 8 , further comprising:

obtaining and storing the opposed-phase sound source that is pre-generated in response to a predetermined accumulated distance driven.

14. The method of claim 13 , further comprising:

updating the stored opposed-phase sound sources as the pre-generated opposed-phase sound source depending on an accumulated distance driven when the accumulated distance driven of the electric vehicle is the predetermined accumulated distance driven.