High-voltage power supplies for vehicles that eliminate low-voltage batteries
A vehicle includes an electric motor, one or more low-voltage components, a high-voltage battery pack, and a direct current to direct current (DC-to-DC) converter. The high-voltage battery pack includes one or more high-voltage battery strings configured to provide a high-voltage output on a high-voltage bus for powering the electric motor. The DC-to-DC converter is connected to the one or more high-voltage battery strings, and is configured to generate a low-voltage output on a low-voltage bus for powering the one or more low-voltage components.
1 . A vehicle comprising:
an electric motor;
one or more low-voltage components; and
a power supply comprising:
a high-voltage battery pack comprising one or more high-voltage battery strings configured to provide a high-voltage output on a high-voltage bus for powering the electric motor; and
a direct current to direct current (DC-to-DC) converter comprising a master DC-to-DC converter, the master DC-to-DC converter connected to the one or more high-voltage battery strings, the DC-to-DC converter configured to generate a low-voltage output on a low-voltage bus for powering the one or more low-voltage components; and
a redundant slave DC-to-DC converter, the redundant slave DC-to-DC converter connected to the one or more high-voltage battery strings and configured to alternatively generate the low-voltage output.
2 . The vehicle of claim 1 , wherein the high-voltage battery pack further comprises:
a low-voltage output terminal connected to the low-voltage bus; and
the DC-to-DC converter, the DC-to-DC converter configured to generate the low-voltage output at the low-voltage output terminal.
3 . The vehicle of claim 2 , wherein the high-voltage battery pack further comprises:
one or more main contactors, each main contactor of the one or more main contactors selectively connecting a corresponding high-voltage battery string to a high-voltage output terminal;
a high-voltage contactor selectively connecting the DC-to-DC converter to the one or more battery strings; and
a low-voltage contactor selectively connecting the DC-to-DC converter to the low-voltage output terminal.
4 . The vehicle of claim 3 , wherein the low-voltage contactor can be closed to connect the DC-to-DC converter to the one or more battery strings for generating the low-voltage output while at least one of the one or more main contactors are open.
5 . The vehicle of claim 1 , further comprising a controller in communication with the master DC-to-DC converter and the redundant slave DC-to-DC converter, the controller configured to perform operations comprising:
monitoring the master DC-to-DC converter;
determining that a failure associated with the master DC-to-DC converter has occurred; and
based on determining that a failure associated with the master DC-to-DC converter has occurred:
activating the redundant slave DC-to-DC converter; and
de-activating the master DC-to-DC converter.
6 . The vehicle of claim 1 , wherein the high-voltage battery pack further comprises the master DC-to-DC converter.
7 . The vehicle of claim 6 , wherein the high-voltage battery pack further comprises the redundant slave DC-to-DC converter.
8 . The vehicle of claim 1 , wherein the power supply further comprises:
a first low-voltage contactor selectively connecting the master DC-to-DC converter to the one or more battery strings;
a second low-voltage contactor selectively connecting the master DC-to-DC converter to the low-voltage bus;
a third low-voltage contactor selectively connecting the redundant slave DC-to-DC converter to the one or more battery strings; and
a fourth low-voltage contactor selectively connecting the redundant slave DC-to-DC converter to the low-voltage bus.
9 . The vehicle of claim 1 , wherein the power supply further comprises a second redundant slave DC-to-DC converter, the second redundant slave DC-to-DC converter connected to the one or more battery strings and configured to alternatively generate the low-voltage output.
10 . The vehicle of claim 1 , wherein the one or more low-voltage components comprise one or more of a critical load, a non-critical load, or a key-off load.
11 . The vehicle of claim 1 , further comprising a supercapacitor configured to store and provide power for an overload or peak load condition.
12 . The vehicle of claim 1 , wherein the vehicle does not include a low-voltage battery for powering the one or more low-voltage components.
13 . A computer-implemented method executed on data processing hardware of a vehicle that causes the data processing hardware to perform operations comprising:
detecting a key-on condition; and
based on detecting the key-on condition, activating a direct current to direct current (DC-to-DC) converter of a high-voltage battery pack to generate a low-voltage output on a low-voltage bus for powering one or more low-voltage components of the vehicle;
detecting an overload or additional load condition; and
based on detecting the overload or additional load condition, activating a second DC-to-DC converter to generate a second low-voltage output on a second low-voltage bus for powering one or more low-voltage components of the vehicle.
14 . The computer-implemented method of claim 13 , wherein the operations further comprise:
detecting a driving mode; and
based on detecting the driving mode, closing one or more main contactors to generate a high-voltage output on a high-voltage bus for powering an electric motor of the vehicle, each main contactor associated with a corresponding battery string of the high-voltage battery pack.
15 . The computer-implemented method of claim 14 , wherein the operations further comprise:
detecting a key-off condition; and
based on detecting the key-off condition, opening the one or more main contactors while leaving the DC-to-DC converter active to power all key-off loads.
16 . The computer-implemented method of claim 14 , wherein the operations further comprise:
detecting a high-voltage safety condition; and
based on detecting the high-voltage safety condition, opening the one or more main contactors while leaving the DC-to-DC converter active.
17 . The computer-implemented method of claim 16 , wherein the high-voltage safety condition is associated with a crash or vehicle service notification.
18 . The computer-implemented method of claim 13 , wherein activating the DC-to-DC converter comprises:
closing a main contactor associated with a high-voltage battery string to generate a high voltage;
closing a first low-voltage contactor to connect the DC-to-DC converter to the generated high voltage; and
closing a second low-voltage contactor to connect the DC-to-DC converter to the low-voltage bus.