Contactor engagement system and method

1. A battery control module for a battery system comprising:

a pulse-width modulation (PWM) module that generates N PWM signals; and

a contactor control module that consecutively applies the N PWM signals to close a contactor,

wherein a first one of the N PWM signals has a first duty cycle,

wherein the first duty cycle is determined based on a temperature and a source voltage of a battery,

wherein application of the first one of the N PWM signals moves the contactor at a first velocity from an open position and application of a second one of the N PWM signals moves the contactor at a second velocity to a closed position,

wherein the first velocity is less than the second velocity, and

wherein N is an integer greater than one.

2. The battery control module of claim 1 , wherein a third one of the N PWM signals moves the contactor at a third velocity that is less than the second velocity.

3. The battery control module of claim 1 , wherein duty cycles of successive ones of the N PWM signals are incremented by a predetermined amount.

4. The battery control module of claim 1 , wherein the first duty cycle is less than 100%, and wherein the second one of the N PWM signals has a second duty cycle that is substantially equal to 100%.

5. A system comprising:

the battery control module of claim 1 ;

a battery subpack that includes the battery; and

the contactor that connects the battery to a load.

6. The battery control module of claim 1 , further comprising a lookup table for determining the first duty cycle based on the temperature and the source voltage.

7. The battery control module of claim 4 , wherein the first duty cycle is predetermined and stored in memory prior to application of the first and second duty cycles.

8. A battery control module for a battery system comprising:

a pulse-width modulation (PWM) module that generates a first PWM signal having a first duty cycle and a second PWM signal having a second duty cycle, wherein the first duty cycle is less than the second duty cycle, and wherein the first duty cycle is determined based on a temperature and a source voltage of a battery; and

a contactor control module that consecutively applies the first PWM signal and the second PWM signal to close a contactor in order to connect the battery to a load,

wherein application of the first PWM signal moves the contactor from an open position to a closed position and application of the second PWM signal maintains the contactor in the closed position.

9. The battery control module of claim 8 , wherein the PWM module generates a third PWM signal having a third duty cycle, wherein the third duty cycle is less than the second duty cycle.

10. The battery control module of claim 9 , wherein the contactor control module applies the third PWM signal to the contactor after applying the second PWM signal, to further maintain the contactor in the closed position.

11. The battery control module of claim 8 , further comprising a lookup table for determining the first duty cycle based on the temperature and the source voltage.

12. A method for operating a battery system comprising:

generating N PWM signals;

applying a first one of the N PWM signals to a contactor to move the contactor at a first velocity from an open position, wherein a first one of the N PWM signals has a first duty cycle, and wherein the first duty cycle is determined based on a temperature, and a source voltage of a battery; and

applying a second one of the N PWM signals to the contactor after applying the first one of the N PWM signals to the contactor to move the contactor at a second velocity to a closed position in order to connect the battery to a load, wherein the first velocity is less than the second velocity, and wherein N is an integer greater than one.

13. The method of claim 12 , further comprising applying a third one of the N PWM signals to the contactor to move the contactor at a third velocity that is less than the second velocity.

14. The method of claim 12 , further comprising incrementing duty cycles of successive ones of the N PWM signals by a predetermined amount.

15. The method of claim 12 , wherein the first duty cycle less than 100%, and wherein the second one of the N PWM signals has a second duty cycle that is substantially equal to 100%.

16. The method of claim 15 , further comprising predetermining the first duty cycle and storing the first duty cycle in memory prior to application of the first and second duty cycles.

17. The method of claim 12 , further comprising connecting the battery to a battery subpack by closing the contactor.

18. A battery system comprising:

a pulse-width modulation (PWM) module that generates N PWM signals;

a contactor; and

a contactor control module that consecutively applies the N PWM signals to close the contactor,

wherein a first one of the N PWM signals has a first duty cycle,

wherein the first duty cycle is determined based on a temperature and a source voltage of a battery,

wherein application of the first one of the N PWM signals moves the contactor from an open position to an intermediate position and application of a second one of the N PWM signals moves the contactor from the intermediate position to a closed position, wherein the intermediate position is between the open position and the closed position, and wherein N is an integer greater than one.

19. The battery system of claim 18 , wherein duty cycles of successive ones of the N PWM signals are incremented by a predetermined amount.

20. The battery system of claim 18 , wherein the first duty cycle less than 100%, and wherein the second one of the N PWM signals has a second duty cycle that is substantially equal to 100%.