Battery management system including switch
A battery management system (BMS) in which a battery protection circuit controls a main switch using hardware without software control, thereby coping with troubles in the BMS or software errors.
1. A battery management system (BMS) for managing a power supply from a battery to an inverter, comprising:
a reference voltage generator connected in parallel to the battery and configured to generate a reference voltage;
a comparator for comparing a battery voltage from a terminal of the battery with the reference voltage output by the reference voltage generator;
a charge pump connected between the reference voltage generator and the comparator; and
a switch for blocking a current flow of the battery according to an output signal generated by the comparator.
2. The BMS of claim 1 , wherein the reference voltage comprises a first reference voltage for determining an overcharge of the battery or a second reference voltage for determining an overdischarge of the battery, and
the comparator is configured to determine whether or not the battery voltage is greater than the first reference voltage, or whether or not the battery voltage is less than the second reference voltage.
3. The BMS of claim 2 , further comprising a transistor that is configured to turn on in response to the output signal generated by the comparator in order to open the switch.
4. The BMS of claim 3 , wherein the comparator is configured to generate a signal that turns on the transistor when the battery voltage is greater than the first reference voltage or the battery voltage is less than the second reference voltage.
5. The BMS of claim 3 , wherein the battery comprises at least two batteries, and the comparator comprises at least two comparators for respectively comparing battery voltages at terminals of the at least two batteries with at least two reference voltages output by the reference voltage generator.
6. The BMS of claim 5 , wherein the charge pump is connected between the reference voltage generator and at least one of the at least two comparators.
7. The BMS of claim 5 , further comprising an OR gate circuit between both the at least two comparators and the transistor,
wherein the transistor is configured to turn on in response to a signal output by the OR gate circuit.
8. The BMS of claim 2 , wherein the comparator is configured to output a reset signal that resets an operation of controlling the switch when the battery voltage is greater than the first reference voltage or the battery voltage is less than the second reference voltage.
9. The BMS of claim 1 , wherein the inverter is configured to supply power to a motor for driving a vehicle.
10. A device for managing a battery comprising:
a reference voltage generator powered by the battery and configured to generate a reference voltage;
a comparator for generating a control signal based on a comparison of a voltage of the battery and the reference voltage;
a charge pump connected between the reference voltage generator and the comparator; and
a switch for interrupting charging or discharging of the battery in accordance with the control signal
wherein the reference voltage generator, the comparator, and the switch are operated to manage the battery without software control.