240. Here, the auxiliary loads 240 may include a load that is implemented separately from the vehicle 10 and is connected to the vehicle 10 by a user for power and/or communication with the vehicle 10. For example, the auxiliary load 240 may be a smart or mobile user device.

Referring to FIG. 2E, in an example high-voltage power supply 200e, the high-voltage contactors 221 are directly connected to the battery strings 210 rather than to the high-voltage bus 40, as compared to the power supply 200d of FIG. 2D. In this way, a DC-to-DC converter 220 may be active without the high-voltage bus 40 having to be electrified. Notably, this arrangement enables the one or more DC-to-DC converters 220 to provide power to key-off loads and/or critical loads without high-voltage cable interconnections being electrified (e.g., in an emergency state or during vehicle service).

Referring to FIG. 2F, an example high-voltage power supply 200f, as compared to the power supply 200e of FIG. 2E, includes the additional auxiliary DC-to-DC converter 220k that is integrated in the battery pack 230 and implements one or more additional DC-to-DC converters 220 (e.g., the master DC-to-DC converter 220a with one or more redundant slave DC-to-DC converters 220b-n) for providing power to the one or more auxiliary loads 240.

Referring to FIG. 2G, an example high-voltage power supply 200g implements the one or more DC-to-DC converters 220, 220a-n separately from a high-voltage multi-string battery pack 230 that implements the one or more battery strings 210 and the positive main contactors 211, as compared to the power supply 200d of FIG. 2D. The power supply 200g may also include the auxiliary DC-to-DC converter 220k for providing power to the auxiliary load(s) 240.

FIG. 3 is a flowchart of an example arrangement of operations for a method 300 of controlling the power supplies 200. Data processing hardware 410 (FIG. 4) may execute instructions stored on memory hardware 420 (FIG. 4) that cause the data processing hardware 410 to perform the operations of the method 300. The data processing hardware 410 and the memory hardware 420 may reside on the controller 16, a PCU ECU, an ECU responsible for the active discharge of a high-voltage bus, or any other ECU or control module of a vehicle 10.

At operation 302, the method 300 includes detecting a key-on condition. For example, a user of the vehicle 10 turns a key or presses a start button to start or turn on the vehicle. At operation 304, the method 300 includes, based on, or in response to, detecting the key-on condition, activating a DC-to-DC converter 220 of a high-voltage battery pack 230 to generate a low-voltage output on a low-voltage bus 50 for powering one or more low-voltage components 30 of a vehicle 10. Here, activating the DC-to-DC converter 220 may include closing a positive main contactor 211 associated with a high-voltage battery string 210 to generate a high voltage, closing a first contactor 221 to connect the DC-to-DC converter 220 to the generated high voltage, and closing a second contactor 222 to connect the DC-to-DC converter 220 to the low-voltage bus 50.

At operation 306, the method 300 includes detecting a driving mode. For example, a user of the vehicle 10 putting the vehicle 10 in gear. At operation 308, the method includes, based on, or in response to, detecting the driving mode, closing one or more positive main contactors 211 to generate a high-voltage output on a high-voltage bus 40 for powering an electric motor (24) of the vehicle 10, each positive main contactor 211 associated with a corresponding battery string 210 of the high-voltage battery pack 230.

At operation 310, the method 300 includes detecting a key-off condition. For example, a user of the vehicle 10 turns a key or presses a stop button to stop or turn off the vehicle. At operation 312, the method 300 includes, based on or in response to, based on detecting the key-off condition, opening the one or more positive main contactors 211 while leaving the DC-to-DC converter 220 active to power all key-off loads 30.

The method 300 may also include detecting a high-voltage safety condition and, based on, or in response to, detecting the high-voltage safety condition, opening one or more positive main contactors 211 while leaving the DC-to-DC converter active 220. Here, the high-voltage safety condition may be associated with a crash or vehicle service notification, for example. The method 300 may further include detecting an overload or additional load condition and, based on, or in response to, 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.

FIG. 4 is a schematic view of an example computing device 400 that may be used to implement the systems and methods described in this document. The computing device 400 is intended to represent various forms of computing devices, such as control modules, controllers, ECUs, and other appropriate computing devices 400 for use in implementing or controlling a vehicle. The components shown here, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of the inventions described and/or claimed in this document.

The computing device 400 includes a processor 410, memory 420, a storage device 430, a high-speed interface/controller 440 connecting to the memory 420 and high-speed expansion ports 450, and a low speed interface/controller 460 connecting to a low speed bus 470 and a storage device 430. Each of the components 410, 420, 430, 440, 450, and 460, are interconnected using various busses, and may be mounted on a common motherboard or in other manners as appropriate. The processor 410 can process instructions for execution within the computing device 400, including instructions stored in the memory 420 or on the storage device 430 to display graphical information for a graphical user interface (GUI) on an external input/output device, such as display 480 coupled to high speed interface 440. In other implementations, multiple processors and/or multiple buses may be used, as appropriate, along with multiple memories and types of memory. Also, multiple computing devices 400 may be connected, with each device providing portions of the necessary operations (e.g., as a server bank, a group of blade servers, or a multi-processor system).

The memory 420 stores information non-transitorily within the computing device