Vehicle system with battery boost and bypass control
A vehicle system according to an exemplary aspect of the present disclosure includes, among other things, a DC/DC converter bus adapted to operate at a first voltage set-point and a low voltage battery bus adapted to operate at a second voltage set-point different from the first voltage set-point.
1. A vehicle system, comprising:
a DC/DC converter bus adapted to operate at a first voltage set-point;
a low voltage battery bus adapted to operate at a second voltage set-point different from said first voltage set-point; and
a boost converter disposed between said DC/DC converter bus and said low voltage battery bus and configured to control current flow between said DC/DC converter bus and said low voltage battery bus.
2. The vehicle system as recited in claim 1 , wherein said boost converter includes at least one switch operable to disconnect said DC/DC converter bus from said low voltage battery bus.
3. The vehicle system as recited in claim 1 , wherein said boost converter includes a bypass switch, an energy storage device, a boost switch, and a diode.
4. The vehicle system as recited in claim 1 , wherein said DC/DC converter bus includes a DC/DC converter and at least one module load.
5. The vehicle system as recited in claim 1 , wherein said low voltage battery bus includes a battery.
6. The vehicle system as recited in claim 1 , wherein said first voltage set-point includes a fixed voltage and said second voltage set-point includes a variable voltage.
7. The vehicle system as recited in claim 1 , comprising a control unit in electrical communication with said DC/DC converter bus and said low voltage battery bus.
8. The vehicle system as recited in claim 7 , wherein said control unit is configured to operate in a charging mode in which said DC/DC converter bus charges a battery of said low voltage battery bus and a support mode in which said low voltage battery bus supports module loads of said DC/DC converter bus.
9. The vehicle system as recited in claim 1 , wherein said vehicle system is part of a low voltage bus of an electrified vehicle.
10. A vehicle system, comprising:
a low voltage battery;
a DC/DC converter configured to charge said battery;
a boost converter connected between said battery and said DC/DC converter and configured to boost voltages from said DC/DC converter; and
a control unit configured to operate in a charging mode where current flows in a first direction to charge said battery and a support mode where current flows in a second, opposite direction to support a module load.
11. The vehicle system as recited in claim 10 , wherein said battery part of a low voltage battery bus and said DC/DC converter is part of a DC/DC converter bus.
12. The vehicle system as recited in claim 11 , wherein said module load is part of said DC/DC converter bus.
13. The vehicle system as recited in claim 10 , wherein said boost converter includes a bypass switch that is selectively closed to define a path of said current flow in said support mode.
14. The vehicle system as recited in claim 13 , wherein said boost converter includes a boost switch that is selectively opened and closed to store energy within an energy storage device during said charging mode.
15. The vehicle system as recited in claim 10 , wherein said low voltage battery is a 12V battery.
16. A method, comprising:
incorporating a boost converter into a vehicle system of an electrified vehicle;
operating the vehicle system in a charging mode in which a DC/DC converter charges a battery in response to a low state of charge condition of the battery; and
operating the vehicle system in a support mode in which the battery supports at least one module load in response to an overload condition of the DC/DC converter.
17. The method as recited in claim 16 , wherein the DC/DC converter is part of a DC/DC converter bus and the battery is part of a low voltage battery bus.
18. The method as recited in claim 17 , comprising:
operating the DC/DC converter bus at a fixed voltage set-point; and
operating the low voltage battery bus at a variable voltage set-point.
19. The method as recited in claim 16 , comprising disconnecting the DC/DC converter from the battery in response to a third condition.
20. A vehicle system, comprising:
a battery;
a DC/DC converter configured to charge said battery; and
a boost converter connected between said battery and said DC/DC converter and configured to boost voltages from said DC/DC converter, said boost converter including at least one switch operable to selectively disconnect said DC/DC converter from said battery.