System and method for supplying electrical power to electrical consumers in an electric or hybrid vehicle

Abstract

System and method for powering electrical consumers of an electric or hybrid vehicle. The invention relates to a power supply system (1) for electrical consumers of an electric vehicle comprising: - a high-voltage battery (8), - two DC-DC converters (4, 6) supplying an on-board network (50), - an energy storage unit (5) connected to the output of the converters (4, 6) and capable of supplying the on-board network (50) in standby mode, - power lines (L2, L5, L6, L7, L8, L10) supplying distribution boxes (12, 13, 14), - the distribution boxes (12, 13, 14), which include electronic switching components (t1, t2, t3, t4, t5, t6) connected to electrical consumers, the power supply system (1) further comprising a coupling device (2, 3) connected to the output of the converters (4, 6). and to the power lines,and comprising at least one electronic switching component(s). (Figure 1)

Description

Title of the invention: System and method for supplying electrical power to electrical consumers of an electric or hybrid vehicle

[0001] The present invention relates to the fields of electricity and automobiles, and more specifically concerns a power supply system for electrical consumers embedded in an electric or hybrid vehicle.

[0002] Electric or hybrid electric vehicles are very often equipped with a lithium-ion battery or equivalent technology, capable of supplying the energy required by an electric motor for traction or propulsion of the vehicle, possibly in conjunction with an internal combustion engine. Such a battery is called a high-voltage battery because the maximum open-circuit voltage at its terminals is generally much higher than that of auxiliary batteries, usually around 12V (volts). However, some auxiliary batteries deliver a voltage of around 48V, this value potentially also being the maximum open-circuit voltage of certain "high-voltage" batteries.

[0003] In an electric or hybrid electric vehicle, the auxiliary battery, often lead-acid, is used to power the vehicle's onboard electrical system, to which the vehicle's control units and low-voltage consumers such as windshield wiper actuators, sensors, or small heating elements are connected. The auxiliary battery also provides power to safety-related vehicle systems such as braking and power steering control systems, while the high-voltage battery is designed to power the vehicle's electric motor and possibly other high-voltage equipment such as an air conditioning compressor. The electrical system to which this equipment is connected is called the vehicle's "high-voltage" system.

[0004] However, anti-pollution standards will prohibit lead-acid batteries, which are also heavy and bulky, which will require, for example, their replacement by small lithium-ion batteries, which are very expensive and which will have to be recharged during periods of non-use of the vehicle, by a direct current - direct current converter connected to the high-voltage battery, the converter allowing the charging of the small lithium-ion battery.

[0005] The small lithium-ion battery must therefore ensure a level of safety preventing the loss of the on-board network, designated ASIL C (for Automotive Safety Integrity Level C as defined by ISO 26262). More specifically, in the event of the loss of one of the on-board network's power sources (DC-DC converter or small lithium-ion battery), the vehicle driver must to be able to park safely, that is to say that the on-board network must still be able to supply 70A (amps) for two minutes in order to power the power steering and braking control systems until the vehicle is parked.

[0006] These safety requirements necessitate a specific sizing of the small lithium-ion battery (or other lead-free technology), which results in a significant cost for the vehicle's electrical system. Furthermore, these safety requirements necessitate preventive maintenance, consisting of regularly replacing this lithium-ion battery. The battery must undergo an ASIL diagnostic demonstrating its proper operation at -30°C (degrees Celsius), or alternatively, it must be supplemented by a heating system for the small lithium-ion battery in winter. In addition, to avoid exceeding the voltage limits of low-voltage electrical consumers, the state of charge of the small lithium-ion battery must be monitored. Thus, for a small lithium-nickel-manganese-cobalt-graphite battery, the state of charge must not exceed 50% so that the voltage across its terminals does not exceed 14.5V (volts).

[0007] The present invention aims to remedy at least in part the aforementioned drawbacks by providing a power supply system for low-voltage electrical consumers of an electric or hybrid vehicle, on board this vehicle, and a method of powering these low-voltage electrical consumers using the power supply system, which make it possible to ensure a sufficient level of safety in the event of the loss of an energy producer of the vehicle's on-board network, without requiring a service battery sized to ensure safe parking of the on-board network.

[0008] To this end, the invention proposes a power supply system for electrical consumers of an electric or hybrid vehicle, comprising: - a battery, capable of supplying the energy necessary for the operation of an electric powertrain of the vehicle, - at least two DC-DC converters, capable of powering the vehicle's on-board electrical system, each converter being connected at its input to a set of battery cells and at its output to the vehicle's on-board electrical system, - an energy storage unit connected at the output of the DC-DC converters, and capable of powering the vehicle's on-board electrical system when the vehicle is in standby mode, - power lines capable of transmitting at least a portion of the energy output from the DC-DC converters to distribution boxes, - distribution boxes, each comprising first electronic switching components capable of transferring the energy transmitted by the power lines to at least a portion of the electrical consumers, the power supply system being characterized in that it further comprises at least one coupling device connected on the one hand to the output of the DC-DC converters and on the other hand to the power lines, the coupling device comprising at least one second electronic switching component.

[0009] In the invention, the battery is capable of powering the electric powertrain; it is therefore a "high-voltage" battery, that is, a battery of electrical accumulators capable of powering an inverter and an electric motor enabling the vehicle to move, unlike a service battery of the prior art. The battery is preferably a lead-free battery, for example, a lithium battery.

[0010] The electrical storage unit is a small lead-free battery, for example lithium, sized solely to power the vehicle's electrical system when the vehicle is in standby mode, and to compensate for the loss of one of the DC-DC converters during load shedding of non-safe loads in the vehicle, carried out by the electronic switching components in less than 500 ms (milliseconds). Load shedding here refers to a power interruption intended to allow the vehicle's electrical system power supplies to maintain it at its nominal voltage.

[0011] Thanks to the invention, the risk of loss of the onboard power supply is reduced by using at least two DC-DC converters, which makes it possible to replace the service battery with an energy storage unit acting as a micro-service battery and therefore less expensive than in the prior art. This storage unit is even less expensive because it is not designed to replace a potentially defective DC-DC converter, but to ensure a safe power supply to the onboard power supply during load shedding of non-safe loads, with the safe power supply to the onboard power supply then being ensured by the functioning DC-DC converter.

[0012] This load shedding is carried out very quickly thanks to the use of electronic switching components or "SmartMOS" in English, which are chips comprising one or more power transistors such as MOSFET transistors (for the English "metal-oxide-semiconductor field-effect transistor"), controlled by a control circuit allowing a circuit to be opened in a short-circuit situation in 100s (microseconds) to 10ms.

[0013] The ability to cut off the power supply to an unsafe consumer using a first and a second electronic disconnecting component, rather than a single electronic disconnecting component and a fuse, which takes longer to open a circuit than an electronic disconnecting component, allows for level safety ASIL C of a braking control system and a vehicle power steering system.

[0014] Thus, the invention makes it possible to meet the safety requirements imposed by international standards, while using an energy storage unit sized for example to supply only 60mA (milliamperes) to the on-board network over one to three days of vehicle inactivity, before being recharged by the DC-DC converter(s), and 125A for 500ms to allow safe parking of the vehicle in the event of the loss of one of the DC-DC converters, assuming that each DC-DC converter is sized to supply 125A.Thus the invention makes it possible to use an energy storage unit limited to 4.5Ah (ampere hour), instead, in the prior art, of a 10Ah battery with lithium, nickel, manganese, cobalt and graphite technology, coupled to an on-board network with fuses, and coupled to the vehicle's high-voltage battery with a single DC-DC converter.

[0015] According to an optional and advantageous feature of the power supply system according to the invention, the power lines transmitting part of the energy from the output of the DC-DC converters to the distribution boxes are first power lines, the power supply system comprising second power lines connected on the one hand to the coupling device and on the other hand to predetermined consumers of the vehicle.

[0016] The predetermined consumers of the vehicle include, for example, safety-critical equipment such as a braking control system and a power steering system, and possibly non-safety-critical, high-amperage equipment such as a powertrain fan. The second electronic switching components of the coupling device are indeed electronic switching components sized to each withstand a current of approximately 40A to 100A, while the first electronic switching components, present in the distribution boxes, are sized to withstand a maximum of 30A, which minimizes the total cost of the electronic switching components of the electrical power supply system according to the invention.

[0017] Thus the coupling device connects, for example, a second power line suitable for supplying only the vehicle's power steering system, to the outputs of the DC-DC converters, via a second electronic switching component capable of withstanding 110A for at least one second.

[0018] Similarly, the coupling device connects, for example, two second power lines capable of supplying only the vehicle's braking control system, at the outputs of the DC-DC converters, via two second electronic switching components, one capable of withstanding 45A for 10 seconds, the other capable of withstanding 75A for 30 milliseconds.

[0019] It is understood that in the invention, each first or second power line is connected to the outputs of the DC-DC converters via at least one second electronic switching component present in the coupling device. In other words, the coupling device includes at least one second electronic switching component for each power line to which it is connected. Each first power line is intended to supply one or more distribution boxes, while each second power line is intended to directly supply a single load, the supply of which uses one or two second power lines.

[0020] Optionally, the coupling device includes two second electronic switching components connecting one of the second power lines to the outputs of the DC-DC converters. The use of two second electronic switching components in series with each other increases the safety level of the power supply system according to the invention.

[0021] For example, the powertrain fan consuming a lot of amperage over time, the coupling device connects it to the outputs of the DC-DC converters by two second electronic switching components in series with each other, which allows in the event of a malfunction of one of the second electronic switching components due to overheating, the other of the second electronic switching components to be used to limit or cut off the supply current of the fan.

[0022] In one embodiment of the invention, at least one power line is electrically connected only to non-safe electrical consumers of the vehicle. This configuration of the power supply system makes it possible to completely cut off the power to these non-safe electrical consumers simply by triggering a second electronic disconnection component connected to this power line. This therefore facilitates securing the vehicle's electrical system in the event of the loss of one of the DC-DC converters.

[0023] A non-safe electrical consumer is defined as an electrical consumer whose operation is not essential for ensuring the safe parking of the vehicle within two minutes. Non-safe consumers therefore include accessories such as power window motors, seat adjustment actuators, the car radio, the passenger compartment's air conditioning and heating equipment, etc. They also include more important components that may not be These components must be powered for the two minutes it takes a driver to pull over to the side of the road. These critical components include, for example, a water pump for a battery cooling system, and the defroster elements for the windshield or rear window.

[0024] O of the first power lines is also, for example, connected to only one of the distribution boxes, and is capable of supplying only electrical consumers whose operation must be ensured in the event of a crash, these electrical consumers including at least one main computer of the vehicle.

[0025] At least one of the electrical consumers is, for example, capable of being powered via an electronic switching component that remains in the conducting state when its control circuit is not powered. This electrical consumer is, for example, the vehicle's main computer, or an alarm.

[0026] Furthermore, two of the distribution boxes are, for example, connected to the same first power line by power conductors originating from a splice of said same first power line. Each distribution box has one or more electrical inputs, each electrical input being connected on one side to a first power line and on the other side to an electrical bus capable of supplying one or more electrical loads via one or more first electronic switching components. One of the electrical buses has, for example, an electrical node from which several branches extend, each capable of supplying a different electrical load via a first electronic switching component, another first electronic switching component being located on the electrical bus upstream of said electrical node.

[0027] According to one embodiment of the invention, the second electronic switching components of the coupling device are integrated into the same printed circuit board. This embodiment reduces the size of the power supply system according to the invention.

[0028] The power supply system according to the invention comprises, for example, a first coupling device connected on the one hand to the output of the DC-DC converters and on the other hand to a first set of power lines, and a second coupling device, separate from the first coupling device, connected on the one hand to the output of the DC-DC converters and on the other hand to a second set of power lines. For example, each coupling device is capable of connecting only five power lines to the outputs of the DC-DC converters. This allows for flexibility in the design of the power supply system, as the number of coupling devices can be adapted to a particular type of electric or hybrid vehicle. The coupling devices are preferably small, low-power integrated components. bulky and identical, which helps to reduce their costs and optimize their placement in the vehicle.

[0029] The invention also relates to a method of supplying electrical power to electrical consumers of an electric or hybrid vehicle equipped with an electrical power supply system for electrical consumers according to the invention, comprising steps of: - measuring a current delivered by the energy storage unit and comparing the measured current to a predetermined maximum current threshold, or monitoring the operation of the DC-DC converters, - detecting overconsumption on the on-board network if the measured current is greater than the predetermined maximum current threshold or if the monitoring step reports an abnormal state of one of the DC-DC converters, the detection step being followed by a step of opening at least one first electronic cut-off component connected to one or more unsafe consumers of the vehicle.

[0030] The power supply method according to the invention is implemented by the power supply system according to the invention and in particular by a current sensor connected to a terminal of the energy storage unit and / or a voltage sensor of the on-board network, optionally current sensors arranged at an output terminal of each DC-DC converter, and a computer connected to these sensors and to control means of the first and second electronic switching components.

[0031] When the vehicle is equipped with an electrical power supply system according to the invention in which at least one power line is electrically connected only to non-safe electrical consumers of the vehicle, the opening control step includes, for example, the opening control of one or more first electronic disconnecting components connected between said power line connected only to non-safe consumers and these, and the opening control of a second electronic disconnecting component connected to said power line connected only to non-safe consumers.

[0032] When the vehicle is equipped with an electrical power supply system according to the invention comprising first power lines connected to the distribution boxes and second power lines connected to predetermined consumers of the vehicle, the opening control step includes, for example, the opening control of a second electronic cutoff component connected to one of said second power lines, connected to a predetermined unsafe consumer.

[0033] Other features and advantages of the invention will become apparent from the following description on the one hand, and from several embodiments given as examples. indicative and not exhaustive, with reference to the attached schematic drawings, on which:

[0034] [Fig. 1] represents a power supply system for electrical consumers of an electric or hybrid vehicle according to the invention, in one embodiment of the invention, and

[0035] [Fig.2] represents a method of supplying electrical power to consumers electric vehicles of the [Fig.1], using its electrical power supply system, in this embodiment of the invention.

[0036] According to an embodiment of the invention shown in [Fig. 1], an electrical power supply system 1 of an electric or hybrid vehicle comprises a battery 8 of electrical accumulators connected in series, these accumulators being, for example, cells using lithium-ion technology. Of course, other technologies are usable, for example, nickel-metal hydride batteries. The battery 8 of the electrical power supply system 1 is a so-called "high-voltage" lead-free battery, the power of which enables the operation of an electric powertrain of the vehicle. Its maximum open-circuit voltage is, for example, between 200V and 800V in this embodiment.

[0037] Battery 8 is connected via its positive and negative terminals to a high-voltage network of the vehicle, not shown but located along the extension of the thick dashed lines on the left of [Fig. 1]. The vehicle's powertrain is directly connected to this high-voltage network. The vehicle's high-voltage network is connected to battery 8 by battery relays, not shown.

[0038] The terminals of the battery 8 are also directly connected to two DC-DC converters 4 and 6, configured to deliver a voltage, for example, between 12V and 14V, to an on-board network 50 of the vehicle, supplying low-voltage consumers of the vehicle. More specifically, a first output of each DC-DC converter 4, 6 is connected to the on-board network 50, and a second output of each DC-DC converter 4, 6 is connected to a vehicle ground. The on-board network 50 here refers to a positive power supply bus connecting the first outputs of the DC-DC converters 4, 6 to coupling devices 2, 3 described later.

[0039] The DC-DC converters 4 and 6 are so-called operating converters, i.e., configured to supply the vehicle's on-board network 50 during the vehicle's operating phases, corresponding to phases during which a monitoring device 10 of the electrical power supply system 1 is activated. This monitoring device 10 is, for example, the vehicle's main computer. An operating phase can therefore correspond to a vehicle driving phase or a phase of "life on board" during which the vehicle is stopped but where a user can use, for example, a multimedia environment of the vehicle.

[0040] DC-DC converters 4 and 6 are, for example, configured to supply the on-board network with a rated power less than or equal to half the maximum power consumption of the on-board network, this maximum power being estimated beforehand during the vehicle design. They are therefore, for example, each capable of delivering a maximum of 125A to the on-board network 50, and each have a rated power between 2kW and 4kW (kilowatts). This helps to limit the cost of the electrical power supply system 1. Depending on the consumption requirements of the on-board network 50, only one of the DC-DC converters 4 or 6, or both DC-DC converters 4 and 6, supply power to the on-board network 50, the monitoring device 10 activating these DC-DC converters 4 or 6 based on a measurement or an estimate of these consumption requirements.Preferably, the supervisory device 10 balances the use of the DC-DC converters 4 and 6 by making them work alternately when only one of them is needed to supply the on-board network 50, in order to extend their service life.

[0041] When the vehicle is in standby mode, the DC-DC converters 4 and 6 are not activated, and the vehicle's electrical system 50 is powered only by an energy storage unit 5. The energy storage unit 5 is a small, lead-free lithium battery capable of delivering a voltage of 12V, connected by its positive terminal to the vehicle's electrical system 50 and by its negative terminal to the vehicle's chassis ground. The energy storage unit 5 is sized only to power the vehicle in standby mode for one to three days. During this standby phase, it must supply 10mA to 60mA of standby current, i.e., 1.5Ah to 4.5Ah. Standby mode or a standby phase of the vehicle corresponds to a vehicle operation in which the monitoring device 10 is in standby mode, with the vehicle's computers receiving minimal power, for example, to receive activation messages only.The vehicle is therefore parked and only certain electrical consumers, such as an alarm or a Bluetooth® module for unlocking the vehicle with a contactless key, are activated.

[0042] A current sensor 51 is connected to one of the terminals of the energy storage unit 5 and sends a measurement of the current 15 supplied by the energy storage unit 5 back to the monitoring device 10. When the current 15 falls below a predetermined low current threshold, or when the voltage of the on-board network 50 falls below a predetermined low voltage threshold, the monitoring device 10 activates at least one of the DC-DC converters 4 and 6 to recharge the energy storage unit 5, temporarily waking the vehicle from standby mode. The sensor current 51 or a voltage sensor of the on-board network 50, therefore acts as a wake-up device for the supervisory device 10. In order to wake up the vehicle quickly, in less than 10ms, the current sensor 51 or the voltage sensor is directly connected to the vehicle's computer bus, called the CAN bus (from the English "Controller Area Network") and which is connected to the supervisory device 10.

[0043] This wake-up device for the supervisory device 10 is alternatively replaced by one or more of the current sensors associated with electronic cut-off components of the electrical power supply system 1, described later, these components being connected to electrical consumers impacted by a drop in the current supplied by the energy storage unit 5. In order to wake up the vehicle quickly, in less than 10ms, this or these current sensors are then directly connected to the vehicle's CAN bus.

[0044] In addition, in order to quickly activate at least one of the DC-DC converters 4 and 6 in standby mode, these are for example connected upstream of the battery relays, so as not to require the activation of the high voltage network, this activation requiring prior safety checks.

[0045] The DC-DC converters 4 and 6 can therefore each be connected at the input to all the cells of the battery 8, or to a subset of these cells. For example, each DC-DC converter 4, 6 is alternatively connected to a distinct subset of the cells of the battery 8, the two corresponding subsets forming a partition of the battery 8.

[0046] During operation, when only one of the DC-DC converters 4, 6 is functioning, the other DC-DC converter 6, 4 is activated upon the current sensor 51 detecting a current value 15 exceeding a predetermined maximum current threshold Smax, for example, 10 A, or upon the onboard network voltage sensor 50 detecting a voltage in the onboard network 50 below a predetermined low voltage threshold. This is because, as soon as the energy storage unit 5 delivers a significant current during operation, the power supplied by the DC-DC converter(s) 6, 4 is insufficient.Alternatively, the activation of the other DC-DC converter 6, 4 is triggered by a current drop detected by one or more sensors associated with switching electronic components connected to electrical consumers impacted by the insufficient power delivered by the active DC-DC converter 4 or 6.

[0047] The connection of the vehicle's electrical consumers to the on-board network is made via coupling devices 2, 3 and distribution boxes 12, 13 and 14.

[0048] Coupling devices 2, 3 replace a fuse box usually located in the prior art between a service battery and distribution boxes.

[0049] A first coupling device 2 comprises an input 21 connected to the on-board network 50 and five outputs, each connected to a power line L1 to L5. The input 21 and the outputs have connection terminals arranged on the same printed circuit board (PCB) in the form of a rectangular or square plate with sides less than 15 cm in length. On this printed circuit board, the input 21 is connected by an electrical trace to an electrical bus 22.

[0050] The electrical bus 22 is connected to the five outputs via power switching electronic components, referred to hereafter as "second switching electronic components" as opposed to "first" switching electronic components located in the distribution boxes 12, 13 and 14.

[0051] Thus: - two second electronic switching components s, connected to each other in series, are connected on one side to the electrical bus 22 and on the other side to the power line Ll, which is connected directly to a fan 11 of the vehicle's powertrain; - another second electronic switching component connects the electrical bus 22 to the power line L2; - another second electronic cutoff component connects the electrical bus 22 to the power line L3, directly connected to a braking control system 7 of the vehicle; - another second electronic cutoff component connects the electrical bus 22 to the power line L4, directly connected to the vehicle's braking control system 7; and - another second electronic switching component connects the electrical bus 22 to the power line L5.

[0052] The second electronic switching components s are, for example, MOSFETs (metal-oxide-semiconductor field-effect transistors), each capable of withstanding at least 40 A of nominal current. They are arranged on the printed circuit board of the first coupling device 2. A current sensor and a control circuit are associated with each second electronic switching component s. The current sensors and associated control circuits are also arranged on the printed circuit board of the first coupling device 2. This integration of the components on the same printed circuit board makes the first coupling device very compact.

[0053] The second coupling device 3 is structurally identical to the first coupling device 2. It has an input 31 connected to the on-board network 50, and five outputs, each connected to a power line L6 to L10. The input 31 is connected on the printed circuit board of the second coupling device 3 to an electrical bus 32.

[0054] Two second electronic switching components s, connected to each other in series, are connected on one side to the electrical bus 32 and on the other side to the power line L10, another second electronic switching component s connects the electrical bus 32 to the power line L6, another second electronic switching component s connects the electrical bus 32 to the power line L7, another second electronic switching component s connects the electrical bus 32 to the power line L8, and another second electronic switching component s connects the electrical bus 32 to the power line L9, which is connected directly to a power steering system 9 of the vehicle.

[0055] The power lines L1, L3, L4, and L9 connected directly to electrical consumers of the vehicle are called second power lines, as opposed to the other power lines, called first power lines, connected to the distribution boxes 12, 13, and 14. These electrical consumers directly connected to the second power lines are also called predetermined consumers. These include safety-critical equipment such as the power steering system 9 and the braking control system 7, and non-safety-critical equipment, which is the vehicle's powertrain fan 11. The first and second power lines take the form, for example, of metallic conductor bars or braided metallic cables.

[0056] Each distribution box 12, 13, 14 has electrical inputs allowing the connection of the distribution box 12, 13, 14 to one or more first power lines L2, L6, L7, L10, and / or to one or more power conductors from, for example, splices of first power lines L5, L8.

[0057] Thus, the distribution box 12 has four electrical inputs B, U, V and A. Electrical input B is connected to a power conductor from a splice of the power line L5. Electrical input U is connected to the power line L2. Electrical input V is connected to the power line L7 and electrical input A is connected to a power conductor from a splice of the power line L8.

[0058] Thus the distribution box 12, housed in the engine compartment of the vehicle and intended to supply the electrical consumers housed in this compartment, is supplied by power lines that can be shared with the other distribution boxes.

[0059] Each electrical input of a distribution box connects the power conductor or power line to which it is connected, or to which it is connected, one or more electrical buses arranged in the distribution box. Each electrical bus supplies one or more electrical consumers of the vehicle via switching devices and supports 20 to 30 A. These switching devices each include one or more first electronic switching components, for example MOSFET transistors, so that each electrical consumer connected to one of the electrical buses is connected via an electronic switching component adapted to the current it draws.

[0060] Thus, the electrical input B is connected to an electrical bus which supplies, in the distribution box, a switching device B1 connected to a battery management module 8 (also called a "Battery Management System"). The switching device B1 comprises depletion-mode MOSFETs, or JFETs (Junction Field Effect Transistors), which conduct in the absence of gate bias, in order to provide minimal power to the battery management module 8 in the vehicle's standby mode. The other first electronic switching components of the distribution box 12 are enhancement-mode MOSFETs. The electrical input U is connected to an electrical bus comprising an electrical node from which two branches extend, each connected to several electrical consumers via switching devices U1 and U2, each comprising one or more first electronic switching components. The switching device U2 is connected to the vehicle's powertrain control means. A first electronic switching component t1 is located between the electrical input U and the electrical node and provides safe redundancy for the power supply interruption means for the electrical consumers connected to the electrical input U.

[0061] The electrical input V is similarly connected to an electrical bus comprising an electrical node from which two branches extend, each connected to several electrical consumers via switching devices VI and V2, each comprising one or more first electronic switching components..

[0062] The switching devices VI and V2 here serve supply pumps for passenger air conditioning systems or battery conditioning 8. A first electronic switching component t2 is disposed between the electrical input V and the electrical node and allows safe redundancy of the means of switching off the supply of electrical consumers connected to the electrical input V.

[0063] Finally, the electrical input A is connected to an electrical bus comprising an electrical node from which two branches extend, each connected to several electrical consumers via switching devices A1 and A2 comprising each one or more first electronic switching components and serving the vehicle's exterior lighting and windshield wipers.

[0064] It should be noted that the description of the distribution boxes given here is simplified, as not all the electrical connections of the various electrical consumers are shown, due to the large number of these consumers. The electrical consumers mentioned in relation to distribution box 12 are not shown in [Fig. 1] to simplify the figure; only a few electrical consumers served by distribution box 14 are shown. Furthermore, in [Fig. 1], the intersections between power conductors or power lines represented by different types of lines do not correspond to electrical connections.

[0065] The distribution box 13 is located under the vehicle's dashboard, on its left side, and has three electrical inputs C, D, and E. Electrical input C connects the power line L6 to an electrical bus that supplies only electrical consumers whose operation must be ensured in the event of a crash. These electrical consumers are low-consumption and include, in particular, the vehicle's main computer, an emergency call device, the flashing lights, an airbag system, a door unlocking system, and a diagnostic port.

[0066] To this end, the electrical bus connected to the electrical input C includes an electrical node from which two branches extend, each connected to a separate switching device Cl, C2, each comprising several first electronic switching components for connecting one or more electrical loads to one of the branches of the electrical bus. The switching device Cl includes depletion-mode MOSFETs or JFETs for powering a main vehicle control unit and a diagnostic connector; these loads must be at least powered or accessible when the vehicle is in standby mode. The other first electronic switching components of the distribution box 13 include enhancement-mode MOSFETs.

[0067] The electrical input D connects a power conductor from a splice of the power line L5 to an electrical bus comprising an electrical node from which two branches extend, supplying several electrical consumers via switching devices D1, D2, each comprising several first electronic power components. The switching devices D1, D2 supply electric motors for window opening and loudspeakers. A first electronic switching component t3 is located between the electrical input D and the electrical node on the electrical bus connected to this electrical input D, and provides safe redundancy for the means of switching off the power supply to the electrical consumers connected to the electrical input D.

[0068] The electrical input E connects a power conductor from a splice of the power line L8 to an electrical bus comprising an electrical node from which three branches extend, supplying several electrical consumers via switching devices El, E2, and E3, each comprising several first electronic power components. The switching devices El, E2, and E3 supply electric window opening motors, an odometer display screen, and a vehicle accessory socket. A first electronic disconnect component t4 is located between the electrical input E and the electrical node on the electrical bus connected to this electrical input E, and provides safe redundancy for the means of disconnecting the power supply to the electrical consumers connected to the electrical input E.

[0069] Similar to the distribution box 13, the distribution box 14 is located under the dashboard of the vehicle, to its right, and has three electrical inputs F, W and G.

[0070] The electrical input F connects a power conductor from a splice of the power line L5 to an electrical bus comprising an electrical node from which two branches extend, each connected to a separate switching device Fl and F2. Each switching device comprises several first electronic switching components for connecting one or more electrical loads to one of the branches of this electrical bus. The switching devices Fl and F2 include depletion-mode MOSFETs or JFETs for powering electrical loads that must be at least powered or accessible when the vehicle is in standby mode, such as an alarm, a computer, and a communication device capable of receiving remote update instructions and connected to the computer. The other switching devices in the distribution box 14 include enhancement-mode MOSFETs.

[0071] The electrical input W connects the power line L10 to an electrical bus comprising an electrical node from which two branches extend, supplying several electrical consumers via switching devices W1, W2, each comprising several first electronic power components. The switching devices W1, W2 supply a cabin fan and seat adjustment actuators. A first electronic switching component t5 is located between the electrical input W and the electrical node on the electrical bus connected to this electrical input W, and provides safe redundancy for the means of switching off the power supply to the electrical consumers connected to the electrical input W.

[0072] The electrical input G connects a power conductor from a splice of the power line L8 to an electrical bus comprising an electrical node from which three branches supply several electrical consumers via of switching devices Gl, G2, and G3, each comprising several first power electronic components. These switching devices supply power to the vehicle's exterior lighting. A first electronic switching component t6 is located between the electrical input G and the electrical node on the electrical bus connected to this electrical input G, providing safe redundancy for the power supply interruption means for the electrical consumers connected to the electrical input G.

[0073] The control circuits and sensors associated with each first or second electronic switching component are connected to the supervisory device 10 by the vehicle's CAN bus.

[0074] We now describe, in relation to [Fig. 2], a method for supplying 100 electrical consumers according to the invention, implemented by the power supply system 1. This system includes, in particular, the supervisory device 10, the control circuits of the first and second electronic switching components, the current sensors associated with these first and second electronic switching components, the current sensor 51 measuring the current 15 delivered by the energy storage unit 5, the voltage sensor of the on-board network 50 and the control circuits of the DC-DC converters 4, 6. These may include current sensors providing a measurement 14 of the current at the output of the DC-DC converter 4 and a measurement 16 of the current at the output of the DC-DC converter 6.

[0075] The electrical supply method 100 according to the invention is implemented while the vehicle is in operation, while the two DC-DC converters 4, 6 are active and supplying a supply current to the vehicle's electrical consumers.

[0076] A first step 102 of the power supply process 100 is the measurement, by the current sensor 51, of a current 15 delivered by the energy storage unit 5.

[0077] In parallel with this first step 102 of the power supply process 100, the supervisory device 10 supervises in a second step 104 of the power supply process 100, the operation of the direct current - direct current converters.

[0078] The next step 106 is the detection of overconsumption on the on-board network 50. This detection takes place if the measured current 15 at the output of the energy storage unit 5 is greater than a predetermined maximum current threshold Smax, set for example at 10A.

[0079] This detection also occurs if the monitoring device 10 determines that the DC-DC converters are not supplying sufficient power to the onboard network 50, for example because the voltage measured on the The onboard network consumption during monitoring step 104 is below a predetermined minimum threshold, or the sum of the currents 14 and 16 measured at the output of the DC-DC converters during monitoring step 104 is strictly less than the sum E of the nominal currents of the various operating electrical consumers. Other means of detecting such overconsumption are, of course, conceivable. For example, monitoring step 104 can determine that a transistor in one of the DC-DC converters is defective or that its efficiency is abnormally low.

[0080] The next step 108 is then the opening command of at least one first electronic switching component connected to one or more non-safe consumers of the vehicle. During this step 108, the monitoring device 10, for example, opens all or part of the first electronic switching components of the switching devices VI, V2, D1, D2, El, E2, E3, W1, W2.

[0081] In addition to or instead of these opening commands, in this step 108, the supervisory device 10 commands, for example, to open all or part of the first electronic switching components t2, t3, t4 and t5.

[0082] In addition to or instead of these opening commands, in this step 108, the supervisory device 10 commands, for example, the following during opening: - the second electronic component is connected to the first power line L7, which is connected only to electrical consumers that can be switched off for two minutes, so as to allow for safe parking of the vehicle, and / or

[0083] - the second electronic component is connected to the first power line L10, this being connected only to electrical consumers that can be switched off for two minutes, so as to allow safe parking of the vehicle and / or

[0084] - the second electronic component is connected to the second power line It, so as to shut off the powertrain fan, which is very energy-intensive, giving the vehicle driver time to park safely.

[0085] Following this step 108 of unsafe load shedding, which can be carried out in less than 500ms given the use of power electronic components, and with safe redundancy given the possible use of two electronic switching components on the same supply line of an unsafe load, the braking control system 7 and the power steering 9 are sufficiently powered to allow the driver of the vehicle to park safely.

[0086] In parallel with the detection step 106 or the opening command 108, the supervision device 10 informs the user of the need to perform safe parking and to call a breakdown service, by a human-machine interaction which may use a screen or a loudspeaker for example.

[0087] It is understood that many ways of implementing the power supply method 100 according to the invention are conceivable, in particular the power supply method 100 according to the invention may include only one of the two steps 102 of measuring the current 15 delivered by the energy storage unit 5 or 104 of supervising the operation of the DC-DC converters.

[0088] Of course, the invention is not limited to the examples just described and many modifications can be made to these examples without departing from the scope of the invention.

Claims

Demands

1. A power supply system (1) for electrical consumers of an electric or hybrid vehicle, comprising: - a battery (8) capable of supplying the energy required to operate an electric powertrain of the vehicle, - at least two DC-DC converters (4, 6) capable of supplying an on-board electrical system (50) of the vehicle, each of the DC-DC converters (4, 6) being connected at its input to a set of cells of the battery (8) and at its output to the on-board electrical system (50) of the vehicle, - an energy storage unit (5) connected at the output of the DC-DC converters (4, 6) and capable of supplying the on-board electrical system (50) of the vehicle when the vehicle is in standby mode, - power lines (L2, L5, L6, L7, L8, L10) capable of transmitting at least a portion of the energy output of the DC-DC converters (4, 6) to distribution boxes (12, 13,14), - the distribution boxes (12, 13, 14), each comprising first electronic switching components (t1, t2, t3, t4, t5, t6) capable of transferring the energy transmitted by the power lines to at least some of the electrical consumers, the power supply system (1) being characterized in that it further comprises at least one coupling device (2, 3) connected on the one hand to the output of the DC-DC converters (4, 6) and on the other hand to the power lines, the coupling device (2, 3) comprising at least one second electronic switching component(s).

2. Power supply system (1) for electrical consumers according to claim 1, wherein the power lines (L2, L5, L6, L7, L8, L10) transmitting part of the power output from the DC-DC converters (4, 6) to the distribution boxes (12, 13, 14) are first power lines, the power supply system (1) comprising second power lines (L1, L3, L4, L9) connected on the one hand to the coupling device (2, 3) and on the other hand to predetermined consumers (11, 7, 9) of the vehicle.

3. Power supply system (1) for electrical consumers according to claim 2, wherein the coupling device (2, 3) comprises two second electronic switching components (s) connecting one of the second power lines (L1) to the outputs of the DC-DC converters (4, 6).

4. Electrical power supply system (1) for electrical consumers according to any one of claims 1 to 3, wherein at least one power line (L1, L7, L10) is electrically connected only to unsafe electrical consumers of the vehicle.

5. Power supply system (1) for electrical consumers according to any one of claims 1 to 4, wherein the coupling device (2, 3) comprises at least one second electronic switching component(s) per power line to which it is connected.

6. Power supply system (1) for electrical consumers according to claim 5, wherein the second electronic switching component(s) are integrated into the same printed circuit board.

7. Power supply system (1) for electrical consumers according to any one of claims 1 to 6, comprising a first coupling device (2) connected on the one hand to the output of the DC-DC converters (4, 6) and on the other hand to a first part of the power lines (L1, L2, L3, L4, L5), and a second coupling device (3) distinct from the first coupling device (2), connected on the one hand to the output of the DC-DC converters (4, 6) and on the other hand to a second part of the power lines (L6, L7, L8, L9, L10).

8. A method for supplying electrical power (100) to electrical consumers of an electric or hybrid vehicle equipped with an electrical power supply system (1) for electrical consumers according to any one of claims 1 to 7, comprising steps of: - measuring (102) a current (15) delivered by the energy storage unit (5) and comparing the measured current (15) to a predetermined maximum current threshold (Smax) or monitoring (104) the operation of the DC-DC converters (4, 6), and - detection (106) of overconsumption on the on-board network (50) if the measured current (15) is greater than the predetermined maximum current threshold (Smax) or if the supervision step (104) reports an abnormal state of one of the DC-DC converters (4, 6), the detection step (106) being followed by an opening control step (108) of at least one first electronic cutoff component (t2, t3, t4, t5) connected to one or more unsafe consumers of the vehicle.

9. Method of supplying power (100) to electrical consumers according to claim 8, wherein the vehicle is equipped with a power supply system (1) for electrical consumers according to claim 4, and wherein the opening control step (108) comprises the opening control of one or more first electronic disconnecting components (t2, t5) connected between said power line (L7, L10) connected only to non-safe consumers and the latter, and the opening control of a second electronic disconnecting component(s) connected to said power line (L7, L10) connected only to non-safe consumers.

10. Method of supplying electrical consumers according to claim 8 or 9, wherein the vehicle is equipped with an electrical consumer supply system (1) according to claim 2, and wherein the opening control step (108) comprises the opening control of a second electronic disconnecting component(s) connected to one of said second power lines (L1), connected to a predetermined non-safe consumer (11).

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