Method and apparatus of controlling output voltage of DC converter for vehicle including driving motor

1. A method of controlling an output voltage of a direct current (DC) converter for a vehicle including a driving motor, the method comprising:

determining, by a controller, whether an event point is present on a driving route;

calculating, by the controller, a distance from a current position of the vehicle to the event point when the event point is present on the driving route;

calculating, by the controller, an expected arrival time when the vehicle is predicted to arrive at the event point based on the distance from the current position to the event point and an effective vehicle speed;

calculating, by the controller, an expected state of charge (SOC) of an auxiliary battery at the event point based on the expected arrival time, a current temperature of the auxiliary battery, and a current SOC of the auxiliary battery;

calculating, by the controller, an SOC difference value between the current SOC of the auxiliary battery and the expected SOC of the auxiliary battery; and

determining, by the controller, the output voltage of the DC converter based on the SOC difference value.

2. The method of claim 1 , wherein the event point includes an acceleration event point and a deceleration event point, and the acceleration event point and the deceleration event point are set based on a gradient of a road, a curvature radius of the road, and a traffic vehicle speed.

3. The method of claim 1 , wherein the effective vehicle speed is an average vehicle speed for a previous predetermined time of the vehicle.

4. The method of claim 1 , wherein in the calculation of the expected SOC of the auxiliary battery at the event point, the expected SOC of the auxiliary battery is calculated using a map table in which expected state of charges of the auxiliary battery that correspond to the expected arrival time, the current temperature of the auxiliary battery, and the current SOC of the auxiliary battery are stored.

5. The method of claim 1 , wherein in the determination of the output voltage of the DC converter based on the SOC difference value, an output voltage range of the DC converter is set to a first range to discharge the auxiliary battery, when the SOC difference value is a negative value.

6. The method of claim 5 , wherein in the determination of the output voltage of the DC converter based on the SOC difference value, the output voltage range of the DC converter is set to a second range to charge the auxiliary battery, when the SOC difference value is a positive value.

7. The method of claim 1 , further comprising:

comparing, by the controller, the current SOC of the auxiliary battery with a controllable SOC,

wherein the determination of the output voltage of the DC converter based on the SOC difference value is performed when the current SOC of the auxiliary battery is greater than the controllable SOC.

8. The method of claim 1 , further comprising:

determining the output voltage of the DC converter to be a maximum value when a main battery discharging control condition is satisfied.

9. The method of claim 8 , wherein the main battery discharging control condition is satisfied when a current SOC of a main battery is a predetermined SOC or greater.

10. An apparatus of controlling an output voltage of a direct current (DC) converter for a vehicle including a driving motor, the apparatus comprising:

a data detector configured to detect data for adjusting the output voltage of the DC converter; and

a controller configured to adjust the output voltage of the DC converter based on the detected data,

wherein the controller is configured to determine whether an event point is present on a driving route, calculate an expected state of charge (SOC) of an auxiliary battery at the event point, calculate an SOC difference value between a current SOC of the auxiliary battery and the expected SOC of the auxiliary battery, and determine the output voltage of the DC converter based on the SOC difference value.

11. The apparatus of claim 10 , wherein the event point includes an acceleration event point and a deceleration event point, and the acceleration event point and the deceleration event point are set based on a gradient of a road, a curvature radius of the road, and a traffic vehicle speed.

12. The apparatus of claim 10 , wherein the controller is further configured to:

calculate a distance from a current position of the vehicle to the event point;

calculate an expected arrival time when the vehicle is predicted to arrive at the event point based on the distance from the current position of the vehicle to the event point and an effective vehicle speed; and

calculate the expected SOC of the auxiliary battery at the event point based on the expected arrival time, a current temperature of the auxiliary battery, and the current SOC of the auxiliary battery.

13. The apparatus of claim 12 , wherein the effective vehicle speed is an average vehicle speed for a previous predetermined time of the vehicle.

14. The apparatus of claim 12 , wherein the controller is configured to calculate the expected SOC of the auxiliary battery using a map table in which expected state of charges of the auxiliary battery that correspond to the expected arrival time, the current temperature of the auxiliary battery, and the current SOC of the auxiliary battery are stored.

15. The apparatus of claim 12 , wherein the controller is configured to e-set an output voltage range of the DC converter to a first range to discharge the auxiliary battery, when the SOC difference value is a negative value.

16. The apparatus of claim 15 , wherein the controller is configured to set the output voltage range of the DC converter to a second range to charge the auxiliary battery, when the SOC difference value is a positive value.

17. The apparatus of claim 10 , wherein the controller is configured to determine the output voltage of the DC converter based on the SOC difference value when the current SOC of the auxiliary battery is greater than a controllable SOC.

18. The apparatus of claim 10 , wherein the controller is configured to determine the output voltage of the DC converter to be a maximum value when a main battery discharging control condition is satisfied.

19. The apparatus of claim 18 , wherein the main battery discharging condition is satisfied when a current SOC of a main battery is equal to or greater than a predetermined SOC.