Battery apparatus, battery management system, and method of diagnosing supply voltage of contactor

1. A battery apparatus, comprising:

a battery pack;

a plurality of contactors configured to connect the battery pack and an external apparatus;

a plurality of driving circuits configured to drive the plurality of contactors based on a supply voltage, respectively; and

a processing circuitry configured to control the plurality of driving circuits to sequentially close the plurality of contactors in a predetermined order, and check the supply voltage before closing each of the plurality of contactors.

2. The battery apparatus of claim 1 , wherein the plurality of contactors includes:

a first contactor connected between a negative terminal of the battery pack and a negative link terminal for connection with the external apparatus;

a second contactor for pre-charging, connected between a positive terminal of the battery pack and a positive link terminal for connection with the external apparatus; and

a third contactor connected between the positive terminal of the battery pack and the positive link terminal, and

wherein the processing circuitry is configured to:

close the plurality of contactors in an order of the first contactor, the second contactor, and the third contactor;

check the supply voltage before closing the first contactor;

check the supply voltage before closing the second contactor; and

check the supply voltage before closing the third contactor.

3. The battery apparatus of claim 1 , wherein the processing circuitry is configured to:

compare the supply voltage with a predetermined voltage before closing each of the plurality of contactors; and

close a corresponding one of the plurality of contactors in response to the supply voltage being equal to or higher than the predetermined voltage.

4. The battery apparatus of claim 3 , wherein the processing circuitry is configured to, in response to the supply voltage being lower than the predetermined voltage, compare the supply voltage with the predetermined voltage after waiting for a predetermined time.

5. The battery apparatus of claim 4 , wherein the processing circuitry is configured to, in response to a number of times of comparing the supply voltage with the predetermined voltage reaching a predetermined number of times, diagnose that there is a fault in the supply voltage.

6. The battery apparatus of claim 5 , wherein the processing circuitry is configured to:

count a counter each time the supply voltage is compared with the predetermined voltage; and

diagnose that there is the fault in the supply voltage in response to a count value of the counter reaching a predetermined value.

7. The battery apparatus of claim 1 , wherein each of the plurality of contactors includes a switch and a relay coil, and

wherein the supply voltage is a voltage that drives the relay coil of each of the plurality of contactors.

8. The battery apparatus of claim 1 , wherein the processing circuitry checks whether the supply voltage before closing each of the plurality of contactors is a stable voltage.

9. A method of diagnosing a supply voltage configured to drive a plurality of contactors including a first contactor and a second contactor configured to connect a battery pack and an external apparatus, the method comprising:

checking the supply voltage before closing the first contactor;

comparing the supply voltage checked before closing the first contactor with a predetermined voltage;

closing the first contactor in response to the supply voltage checked before closing the first contactor being equal to or higher than the predetermined voltage;

checking the supply voltage before closing the second contactor;

comparing the supply voltage checked before closing the second contactor with the predetermined voltage; and

closing the second contactor in response to the supply voltage checked before closing the second contactor being equal to or higher than the predetermined voltage.

10. The method of claim 9 , further comprising, in response to the supply voltage checked before closing the first contactor being lower than the predetermined voltage, comparing the supply voltage checked after waiting for a predetermined time with the predetermined voltage.

11. The method of claim 10 , further comprising diagnosing that there is a fault in the supply voltage in response to a number of times of comparing the supply voltage with the predetermined voltage reaching a predetermined number of times.

12. The method of claim 9 , further comprising, in response to the supply voltage checked before closing the second contactor being lower than the predetermined voltage, comparing the supply voltage checked after waiting for a predetermined time with the predetermined voltage.

13. The method of claim 12 , further comprising diagnosing that there is a fault in the supply voltage in response to a number of times of comparing the supply voltage with the predetermined voltage reaching a predetermined number of times.

14. The method of claim 9 , wherein each of the plurality of contactors includes a switch and a relay coil, and

wherein the supply voltage is a voltage that drives the relay coil of each of the plurality of contactors.

15. The method of claim 9 , wherein the checking of the supply voltage before closing the second contactor checks whether the supply voltage is a stable voltage.

16. A battery management system configured to control a plurality of contactors including a first contactor and a second contactor configured to connect a battery pack and an external apparatus, the battery management system comprising:

a first driving circuit configured to drive the first contactor based on a supply voltage;

a second driving circuit configured to drive the second contactor based on the supply voltage; and

a processing circuitry configured to:

check the supply voltage before closing the first contactor;

control the first driving circuit to close the first contactor in response to the supply voltage checked before closing the first contactor being equal to or higher than a predetermined voltage;

check the supply voltage before closing the second contactor; and

control the second driving circuit to close the second contactor in response to the supply voltage checked before closing the second contactor being equal to or higher than the predetermined voltage.

17. The battery management system of claim 16 , wherein the processing circuitry checks whether the supply voltage before closing the second contactor is a stable voltage.