Control system for controlling a vehicle power supply system

Abstract

A control system 110 for controlling a vehicle power supply system (200, figure 2), the control system having a control unit 300 of the supply system configured to issue a control signal(s) to control

Description

TECHNICAL FIELD The present disclosure relates to a control system for controlling a vehicle power supply system. Aspects of the invention relate to a control system for controlling a vehicle power supply system, to a vehicle power supply system, and to a vehicle comprising said systems. BACKGROUND Battery electric vehicles (BEVs) comprise a traction motor and a traction battery for supplying electrical energy to the traction motor. BEVs also typically comprise a lower voltage auxiliary battery for powering selected vehicle systems when the traction battery is unavailable. The traction battery is typically referred to as the high-voltage battery, and the auxiliary battery is typically referred to as the low-voltage battery. It is against this background that the present invention has been developed. SUMMARY OF THE INVENTION Aspects and embodiments of the invention provide a control system for controlling a vehicle power supply system, a vehicle power supply system, and a vehicle comprising said systems as claimed in the appended claims. According to an aspect of the present invention there is provided a control system for controlling a vehicle power supply system, wherein the control system comprises: a control unit of the vehicle power supply system configured to issue one or more control signals to control one or more sub-systems of the vehicle powersupply system, wherein the control unit has an electrical power input; a control system connector comprising a plurality of connection points, wherein the control system connector is configured to be connected to a low-voltage electrical power source via one or more of the connection points; and a direct-current to direct-current (DCDC) convertor having a first set of connections which together define a low-voltage connection of the DCDC convertor, and second set of connections which together define a high-voltage connection of the DCDC convertor, wherein the electrical power input of the control unit is connected to both the control system connector via one or more of the connection points and to the low-voltage connection of the DCDC convertor. Optionally, the high-voltage connection of the DCDC convertor is configured to be connected to a high-voltage electrical power source. The DCDC convertor may be a bi-directional DCDC convertor. The present invention is advantageous as the control unit has a redundancy in its power supply such that it is still able to operate even if one power supply is unavailable. Optionally the control unit may be configured to issue a control signal to control a switching sub-system of the vehicle power supply system. This is advantageous as the switching sub-system may still be controlled in the event of one of the power supplies being unavailable. The control system may optionally comprise a contactor driver configured to operate one or more switches of the switching sub-system, wherein the contactor driver comprises an electrical power input which is connected to both the control system connector via one or more of the connection points and to the low-voltage connection of the DCDC convertor. This is advantageous as the contactor driver has a redundancy in its power supply such that it is still able to operate if one power supply is unavailable. The electrical power input of the control unit and the electrical power input of the contactor driver may be connected to a common first connection point of the control system connector by a first common connection path and connected to the low-voltage connection of the DCDC convertor by a second common connection path. This provides efficient power routing and allows for the power supply to both the control unit and the contact driver to be controlled by disconnection of the common connection paths. In one example the second common connection path may comprise an external portion having a first end and a second end, wherein the first end of the external portion is connected to a second connection point of the control system connector and the second end of the external portion is connected to a third connection point of the control system connector. The external portion of the second common connection path facilitates physical access to the second common connection path to allow for physical disconnection of the second common connection path should the need arise. Optionally the external portion of the second common connection path at least partially comprises a first electrical conductor in the form or a wire or a cable which may be cut by wire or cable cutting equipment. The second common connection path optionally comprises a cable connector having a plurality of connection points, where the second connection point of the control system connector may be electrically connected to a first connection point of the cable connector, and the third connection point of the control system connector may be electrically connected to a second connection point of the cable connector. Furthermore, a first end of the first electrical conductor may be electrically connected to the first connection point of the cable connector via the cable connector and a second end of the first electrical conductor may be electrically connected to the second connection point of the cable connector via the cable connector. The cable connector advantageously facilitates connection of the first electrical conductor into the second common connection path. The control system may comprise a third common connection path having a first end and a second end, wherein the first end of the third common connection path is electrically connected to the first connection point of the control system connector via the control system connector, and wherein the second end of the third common connection path is electrically connected to the low-voltage electrical power source. The third common connection path facilitates physical disconnection of the power supply from the low-voltage power source to the first common connection path should the need arise. Optionally, the third common connection path comprises a fuse located proximate the low-voltage power source. In one example the third common connection path may at least partially comprise a second electrical conductor in the form of a wire or a cable. The first and second electrical conductors may be packaged together within a common electrically insulting cover to form a control unit power supply cable. Packaging the first and second electrical conductors together in a single cable portion is advantageous as both may be cut by wire or cable cutting equipment to disconnect both power supplies from the control unit and optionally also the contact driver. This may be beneficial in an emergency situation such as a road accident. Optionally the low-voltage connection of the DCDC convertor may comprise a low-voltage output and a low-voltage input, wherein the low-voltage input is connected to both a connection point of the control system connector and to the low-voltage output of the convertor. This provides the DCDC convertor with a redundancy in its power supply such that it is still able to operate even if one power supply is unavailable. The low-voltage output of the DCDC convertor may optionally be configured to be connected to the low-voltage electrical power source so that the low-voltage power source may be charged by the high-voltage power source via the DCDC convertor. If the DCDC convertor is bi-directional, the low-voltage power source may be used to power at least some vehicle systems which are configured to operate at the voltage of the high-voltage power source. The control system may comprise an on-board convertor, wherein the on-board convertor comprises an electrical power input which is connected to both a connection point of the control system connector and to the low-voltage connection of the DCDC convertor. This provides the on-board convertor with a redundancy in its power supply such that it is still able to operate even if one power supply is unavailable. According to another aspect of the present invention there is provided a vehicle power supply system comprising: the control system described above; a high-voltage battery; and a low-voltage battery, wherein the high-voltage battery is connected to the high-voltage connection of the DCDC convertor, and wherein the low voltage battery is connected to at least one connection point of the control system connector. According to a further aspect of the present invention there is provided vehicle comprising the vehicle power supply system. The control unit power supply cable may be located in an openable compartment of the vehicle and configured so that it may be cut by cable cutting equipment. This position is advantageous as it may be accessed by an emergency responder in an emergency situation. Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and / or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and / or features of any embodiment can be combined in anyway and / or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and / or incorporate any feature of any other claim although not originally claimed in that manner. BRIEF DESCRIPTION OF THE DRAWINGS One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a vehicle in accordance with an embodiment of the invention; Figure 2 shows a schematic view of a vehicle power supply system comprising a battery system; and Figure 3 shows a schematic diagram of a control system for controlling the vehicle power supply system of Figure 2. DETAILED DESCRIPTION A vehicle 100 in accordance with an embodiment of the present invention is described herein with reference to the accompanying Figure 1. As shown in Figure 1, a control system 110 for controlling a vehicle power supply system 200 of the vehicle 100 is installed in the vehicle 100. Figure 2 shows is a schematic view of a vehicle power system 200 of the vehicle 100. The power supply system 200 generally comprises a high-voltage battery system 210, a load bus 220, an on-board charger (OBC) 230, and a low-voltage battery 224. In the present embodiment, the vehicle 100 is a battery electric vehicle (BEV), but in other embodiments, the vehicle 100 may be a hybrid electric vehicle (HEV). In the present embodiment, the battery system 210 comprises first and second batteries 211,212 which may be connected in series by closure of first configuration switch 213, or in parallel by closure of second configuration switches 214, 215. The configuration switches 213, 214, 215 together form a battery configuration switching sub-system 205 of the power supply system 200. In Figure 2, the first configuration switch 213 is shown as closed for illustrative purposes. When the first configuration switch 213 is closed, second configuration switches 214, 215 are open to prevent the batteries being connected in series and in parallel at the same time. Similarly, when second configuration switches 214, 215 are closed, the first configuration switch 213 is open. The battery system 210 is capable of being charged by either a 400V or 800V supply. Having the capability to accept, for example, substantially 800V (e.g. a voltage between 450V to 850V) or substantially 400V (e.g. a voltage between 250V to 450V) at the same input allows for a flexible system capable of operating with different voltage requirements. The load bus 220 can be directly connected to the high-voltage battery system 210 by closing load bus switches 216, 217. The load bus switches 216, 217 together form a load bus connection switching sub-system 206 of the power supply system 200. When the load bus switches 216, 217 are closed and the high-voltage battery system 210 is configured with the batteries 211,212 connected in series, in this configuration the high-voltage battery system 210 provides a substantially 800V supply to the load bus 220. The load bus 220 comprises circuitry which connects the high-voltage battery system 210 to one or more inverters of the vehicle 100 which, in turn, control one or more electric motors for providing motive power to the vehicle 100 during driving. In the present embodiment, the load bus 220 comprises high voltage and ground connections 221 to an inverter mounted in the front of the vehicle, and respective high voltage and ground connections 222 to an inverter mounted in the rear of the vehicle. The load bus 220 additionally comprises a DCDC converter 223 for converting the high-voltage supply from the traction battery 210 to a nominal 12V supply for powering auxiliary vehicle systems and for providing power to the low-voltage battery 224 which is a nominal 12V battery. The DCDC convertor 223 may be a bi-directional convertor. The DCDC convertor 223 comprises a sub-system of the power supply system 200. The vehicle 100 is provided with an electrical charging port 225 for receiving an electrical charging plug of an external electrical power supply. In Figure 2, the port 225 is shown schematically and comprises respective first, second and third inlet portions 226, 227, 228. In the present embodiment, the first and second inlet portions 226, 227 are configured to receive respectively the pins of a high-voltage DC charger. Charging port switches 241,242 are operable to directly connect the first and second inlet portions 226, 227 to the battery system 210. The charging port switches 241,242 together form a charging port connection switching subsystem 207 of the power supply system 200. When the vehicle power system 200 is connected to an external DC power supply via the first and second inlet portions 226, 227, and the battery system 210 is arranged in the series connection configuration with first configuration switch 213 closed and second configuration switches 214, 215 open, the batteries 211,212 of the high-voltage battery system 210 are able to be charged by power provided by the high-voltage DC charger. The third inlet portion 228 of the port 225 is configured to receive the pins of an AC charger. The third inlet portion 228 of the charging port 225 is connected directly to the OBC 230. The OBC 230 comprises an AC to DC converter 231 and a boost convertor 232. The OBC 230 comprises a sub-system of the power supply system 200. OBC switches 233, 234 are operable to connect the OCB 230 to the battery system 210. The OBC switches 241, 242 together form an OBC connection switching sub-system 208 of the power supply system 200. When the vehicle power system 200 is connected to an external AC power supply, and the battery system 210 is arranged in the parallel connection configuration with first configuration switch 213 open and second configuration switches 214, 215 closed, the batteries 211,212 of the high-voltage battery system 210 are able to be charged by power provided by the AC charger. It is not possible to drive the vehicle 100 when the high-voltage battery system 210 is arranged in the parallel connection configuration. However, the boost convertor 232 enables the supply of substantially 800V to the load bus 220 even when the high-voltage battery system 210 is arranged in the parallel connection configuration to enable the battery system 210 to be used to power vehicle accessories such as climate control and entertainment to avoid rapid depletion of the low-voltage (nominal 12V) battery 224. The OBC switches 233, 234 are closed in this mode of operation. The switches of battery configuration switching sub-system 205, the load bus connection switching sub-system 206, the charging port connection switching sub-system 207, and the OBC connection switching sub-system 208 are electrically operated switches which require an electrical power supply in order to operate. The switches of these subsystems are arranged so that they default to an open condition when no power is supplied. In the present embodiment, the switches are electromagneticswitches which close when an electric current is supplied to the switch, and open when there is no electric current supplied to the switch. Figure 3 shows a schematic diagram of the control system 110 for controlling the vehicle power supply system 200. The control system 110 comprises a control unit 300 of the vehicle power supply system 200, the DCDC convertor 223, the OBC 230, and a contact driver 302. In this example, the control unit 300 is configured to control the OBC 230, the DCDC convertor 223, and the contact driver 302 - which in turn controls operation of the power bus switching sub-system 206. However, in other examples, the control unit may be configured to control other sub-systems of the vehicle power supply system 200 such as the battery configuration switching sub-system 205, the charging port connection switching sub-system 207, and / or the OBC connection switching sub-system 208. The contact driver 302 is configured to open or close the load bus switches 216,217 of the power bus switching sub-system 206 in dependence on a voltage signal received on control line 303 from the control unit 300. Operation of the DCDC convertor 223 and the OBC 230 is controlled by the control unit 300 by in dependence on voltage signals received from the control unit 300 on control lines 312, 314 respectively. The control system 110 comprises a control system connector 320 which has a plurality of connection points to facilitate connection of the DCDC convertor 223, the control unit 300, the contact driver 302 and the OBC 230 to the low-voltage battery 224. The DCDC convertor 223 has first pair of connections 304, 305 which together define a low-voltage connection 306 ofthe DCDC convertor 223, and second pair of connections 308, 309 which together define a high-voltage connection 310 of the DCDC convertor 223. The high-voltage connection 310 of the DCDC convertor is connected to the high-voltage battery system 210. The connection 304 ofthe low-voltage connection 306 comprises a low-voltage electrical power input ofthe DCDC convertor 223, and the connection 305 ofthe low-voltage connection 306 comprises a low-voltage electrical power output of the DCDC convertor 223. The DCDC convertor 223 is connected to the chassis ofthe vehicle 100 via ground connection path 311. The connection 304 (low-voltage input) of DCDC convertor223 is connected to a connection point 307 ofthe control system connector 320 by a connection path 321, and the connection 305 (low-voltage output) of the DCDC convertor 223 is connected to the low-voltage battery 224 by a connection path 322. In this example, the low-voltage electrical power output ofthe DCDC convertor 223 is supplied to the low-voltage battery 224 without passing through the control system connector 320 - instead passing through another connector (not shown). However, this is not essential, and in another embodiment the low-voltage electrical power output of the DCDC convertor 223 may be supplied to the low-voltage battery 224 via a connection path which passes through the control system connector 320. The control unit 300 has an electrical power input 324 which is connected to a connection point 313 ofthe control system connector 320 by a connection path 325. The contact driver 302 comprises an electrical input 326 which is connected to the connection path 325 by a connection path 327. Consequently, the electrical power input 324 of the control unit 300 and the electrical power input 326 of the contact driver 302 are connected to a common connection point 313 (which may be a first connection point) of the control system connector 320 by first common connection path 325. The OBC 230 has an electrical power input 328 which is connected to a connection point 315 of the control system connector 320 by a connection path 329. The connection path 321 is connected to the low-voltage battery 224 by a connection path 330 which connects to a connection point 316 of the control system connector 320. The connection points 307, 305 of the control system connector 320 are electrically connected via the control system connector 320. Similarly, the first common connection path 325 is connected to the low-voltage battery 224 by a connection path 331 which connects to a connection point 317 of the control system connector 320 so that the connection points 313, 317 of the control system connector 320 are electrically connected via the control system connector 320. Because the connection path 331 connects to the common connection path 325 which supplies power to both the control unit 300 and the contact driver 302, the connection path 331 is a common connection path 331. Finally, the connection path 329 is connected to the low-voltage battery 224 by a connection path 332 which connects to a connection point 318 of the control system connector 320 so that the connection points 315, 318 of the control system connector 320 are electrically connected via the control system connector 320. Each of the connection paths 330, 331, 332 are connected at a respective second end to the low-voltage battery 224 via fuses located in a fuse box 333. A connection path 334 is connected to the connection path 322 which connects the low-voltage output of the DCDC convertor 223 to the low-voltage battery 224. The low-voltage input of the DCDC convertor 223 is connected to the connection path 334 by a connection path 335. Similarly, the electrical power input 328 of the OBC is connected to the connection path 334 by a connection path 336. The DCDC convertor 223 and the OBC 230 therefore have a redundancy of power supply such that, should one of the high-voltage battery system 210 or the low-voltage battery 224 be unavailable (for example because of a lack of charge), the DCDC convertor 223 and the OBC 230 will still be operational, powered by the available high 210 or low 224 voltage power supply. The control unit 300 and the contact driver 302 have similar power supply redundancy to the DCDC convertor 223 and the OBC 223. However, in this case the connection path 327 - which connects the electrical power input 326 of the contact driver 302 to the electrical power input 324 of the control unit 300 - is connected to the connection path 334 by a connection path 337 which passes out of, and back into, the control system connector 320. Because the connection path 337 connects to both the electrical power input 324 of the control unit 300 and the electrical power input 326 of the contact driver 302, the connection path 337 is a second common connection path 337. The second common connection path 337 comprises two internal portions 350, 351 which are connected to respective connection points of the control system connector 320, and an external portion 338 which has a first end 339 and a second end 340. The first end 339 of the external portion 338 is connected to a connection point 319 (which may be a second connection point) of the control system connector 320, and the second end 340 of the external portion 338 is connected to another connection point 323 (which may be a third connection point) of the control system connector 320. Consequently, the external portion 338 of the second common connection path 337 is connected to the internal portions 350, 351 of the second common connection path 337 via the control system connector 320. The external portion 338 of the second common connection path 337 comprises a first electrically conductive wire 341. Although a wire 341 is described in this example, it will be understood that any suitable electrical conductor or cable may be used. The second connection point 319 of the control system connector 320 is connected to a first connection point 342 of a cable connector 343 by a connection path 352, and the third connection point 323 of the control system connector 320 is connected to a second connection point 344 of a cable connector 343 by a connection path 353. A first end 345 of the first electrically conductive wire 341 is connected to the first connection point 342 of the cable connector 343 via the cable connector 343, and a second end 346 of the first electrically conductive wire 341 is connected to the second connection point 344 of the cable connector 343 via the cable connector 343. Consequently, the first electrically conductive wire 341 is connected to the connection paths 352, 353 via the cable connector 343. The common connection path 331 (which may be a third common connection path) has a first end 354 which is connected to the connection point 317 of the control system connector 320, and a second end 355 which is connected to the low-voltage battery 224 as described above. The common connection path 331 comprises a second electrically conductive wire 356 which is packaged together with the first electrically conductive wire 341 within a common electrically insulting cover to form a control unit power supply cable. Although a wire 356 is described in this example, it will be understood that any suitable electrical conductor or cable may be used. In use, when the control system 110 is installed in the vehicle 100, the control unit power supply cable is located in an openable compartment of the vehicle (such as a front or rear luggage compartment) and configured so that it may be cut by cable cutting equipment. When this is done, the electrical power supply is cut off to both the control unit 300 and the contactor driver 302 from each of the low-voltage output of the DCDC convertor 223 and the low-voltage battery 224. The power supplies to the DCDC convertor 223 itself, and to the OBC 230 from the low-voltage output of the DCDC convertor 223 and the low-voltage battery 224 are unaffected by this such that both the DCDC convertor 223 and the OBC 230 remain functional. It will be appreciated that various changes and modifications can be made to the present invention without departing from the scope of the present application. In particular, the electrical power input 324 of the control unit 300 and the electrical power input 326 of the contact driver 302 may be connected to the low-voltage battery 224 and the low-voltage output of the DCDC convertor 223 by independent connection paths and not common connection paths 325, 337 as described above. All of the connection paths to the low-voltage output of the DCDC convertor 223 may be internal such that no external portion which passes out of and back into the control system connector is used. In addition, the way in which various connection paths and electrical conductors connect together need not be as described above with reference to the connectors 320, 343 and any suitable connection architecture may be used. As used herein, a connection path relates to any electrically conductive path comprising any number of conductors or other electrically conductive components.

Claims

1. A control system for controlling a vehicle power supply system, wherein the control system comprises:a control unit of the vehicle power supply system configured to issue one or more control signals to control one or more sub-systems of the vehicle power supply system, wherein the control unit has an electrical power input;a control system connector comprising a plurality of connection points, wherein the control system connector is configured to be connected to a low-voltage electrical power source via one or more of the connection points; anda direct-current to direct-current convertor having a first set of connections which together define a low-voltage connection of the convertor, and second set of connections which together define a high-voltage connection of the convertor, wherein the high-voltage connection of the convertor is configured to be connected to a high-voltage electrical power source,wherein the electrical power input of the control unit is connected to both the control system connector via one or more of the connection points and to the low-voltage connection of the convertor.

2. The control system of claim 1, wherein the control unit is configured to issue a control signal to control a switching sub-system of the vehicle power supply system.

3. The control system of claim 2, comprising a contactor driver configured to operate one or more switches of the switching sub-system, wherein the contactor driver comprises an electrical power input which is connected to both the control system connector via one or more of the connection points and to the low-voltage connection of the convertor.

4. The control system of claim 3, wherein the electrical power input of the control unit and the electrical power input of the contactor driver are connected to a common first connection point of the control system connector by a first common connection path and connected to the low-voltage connection of the convertor by a second common connection path.

5. The control system of claim 4, wherein the second common connection path comprises an external portion having a first end and a second end, wherein the first end of the external portion is connected to a second connection point of the control system connector and the second end(340) of the external portion is connected to a third connection point of the control system connector.

6. The control system of claim 5, wherein the external portion of the second common connection path at least partially comprises a first electrical conductor in the form or a wire or a cable.

7. The control system of claim 6, wherein the second common connection path comprises a cable connector having a plurality of connection points, wherein the second connection point of the control system connector is electrically connected to a first connection point of the cable connector and the third connectionpoint of the control system connector is electrically connected to a second connection point of the cable connector, and wherein a first end of the first electrical conductor is electrically connected to the first connection point of the cable connector via the cable connector and a second end of the first electrical conductor is electrically connected to the second connection point of the cable connector via the cable connector.

8. The control system of claim 6 or 7, comprising a third common connection path having a first end and a second end, wherein the first end of the third common connection path is electrically connected to the first connection point, and wherein the second end of the third common connection path is electrically connected to the low-voltage electrical power source.

9. The control system of claim 8, wherein the third common connection path at least partially comprises a second electrical conductor in the form of a wire or a cable, wherein the first and second electrical conductors are packaged together within a common electrically insulting cover to form a control unit power supply cable.

10. The control system of any preceding claim, wherein the low-voltage connection of the convertor and a low-voltage input, wherein the low-voltage input is connected to both a connection point and to the low-voltage output of the convertor.

11. The control system of claim 10, wherein the low-voltage output of the convertor is configured to be connected to the low-voltage electrical power source.

12. The control system of any preceding claim, comprising an on-board convertor, wherein the onboard convertor comprises an electrical power input which is connected to both a connection point of the control system connector and to the low-voltage connection of the convertor.

13. A vehicle power supply system comprising:the control system of any one of claims 1 to 12;a high-voltage battery; anda low-voltage battery,wherein the high-voltage battery is connected to the high-voltage connection of the convertor, and wherein the low voltage battery is connected to at least one connection point of the control system connector.

14. A vehicle comprising the vehicle power supply system of claim 13.

15. The vehicle of claim 14 when dependent on claim 9, wherein the control unit power supply cable is located in an openable compartment of the vehicle and configured so that it may be cut by cable cutting equipment.Application No: GB2409017.7Examiner: Andrew PhillipsClaims searched: 1-15Date of search: 18 December 2024Patents Act 1977: Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance A - US 2015 / 0232081 Al (SLOSARCZYK et al.) See especially: figures 1-2 ¶graphs [0034]-[0048], A - US 2016 / 0001719 Al (FROST et al.) See especially: figure 1 ¶graphs [0061]-[0064], A - US 2024 / 0067160 Al (KHARPURI et al.) See especially: figure 1 ¶graphs [0004J-[0008], [0019], [0027], A - US 2017 / 0106899 Al (XU et al.) See especially: figures 2, 7 &whole description. A - US 2011 / 0168462 Al (STANEK et al.) See especially: figures 1-2 &whole description. A - US 2019 / 0176642 Al (DIAB et al.) See especially: figure 1 &whole description.Categories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of same category. before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:International Classification:Subclass Subgroup Valid From B60L 0058 / 10 01 / 01 / 2019 B60L 0050 / 60 01 / 01 / 2019 B60R 0016 / 033 01 / 01 / 2006 H02J 0007 / 00 01 / 01 / 2006

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