Onboard network for an electric vehicle

Abstract

The invention relates to an onboard network (1) for an electric or hybrid vehicle, comprising: - a first subnetwork (2) comprising a first electrical energy storage unit (3) at a first DC voltage, a DC / AC voltage converter (4), and the electrical stator winding of a rotary electric machine; - a second subnetwork (11) comprising a second electrical energy storage unit (12) at a second DC voltage, capable of electrically powering electrical consumers that have a rated voltage equal to the second DC voltage; - a third subnetwork (80) at a third DC voltage, capable of electrically powering electrical consumers that have a rated voltage equal to the third DC voltage, the onboard network comprising: - a first DC / DC converter (10) for converting the first DC voltage into the second DC voltage and vice versa; and - a second DC / DC converter (71) for converting the second DC voltage into the third DC voltage and vice versa.

Description

[0001] On-board network for electric vehicles

[0002] The present invention relates to an on-board network for an electric or hybrid vehicle.

[0003] Such an on-board network refers to the electrical circuit on board a vehicle and used to power the rotating electrical machine for propelling the vehicle, but also the various electrical consumers on board the vehicle and contributing to its proper functioning, meeting, for example, safety or comfort requirements.

[0004] These electrical consumers belong, for example, to a set of vehicle air conditioning consumers, being chosen, for example, from all or part of the following consumers: valves, collector, fan, water pumps, air conditioning compressor, high voltage heating module on the water loop, etc.

[0005] These electrical consumers belong, for example, to a set of vehicle lighting or vehicle window wiping consumers, being, for example, chosen from all or part of the following consumers: front headlight, rear headlight, front windscreen wiper, rear windscreen wiper, front defrost module, rear defrost module, etc.

[0006] These electrical consumers belong, for example, to a set of vehicle propulsion consumers, being chosen, for example, from all or part of the following consumers: wired steering or braking control, active suspension, etc.

[0007] These electrical consumers belong, for example, to a set of consumers for driving assistance, called “ADAS” in English.

[0008] These electrical consumers belong, for example, to a set of consumers for the proper functioning of the vehicle interior, being for example chosen from all or part of the following consumers: door window regulator, door lighting, seat heating panel, trunk opening actuator, hood opening actuator, electrical socket in the trunk, etc.

[0009] The on-board network comprises, in a known manner, two sub-networks differing in the value of the direct voltage that they carry. A first sub-network carries a first direct voltage, in particular for supplying the stator of the electric propulsion machine of the vehicle, and a second sub-network carries a second direct voltage for supplying all or part of the aforementioned consumers. The on-board network comprises a first DC / DC converter for converting the first direct voltage into the second direct voltage, and vice versa.

[0010] Such an on-board network is rigid in operation and does not allow for the simple selective integration of new generation electrical consumers that may have a higher specific nominal voltage in order to provide more power for the electrical consumers. Furthermore, new needs require the addition of additional electrical consumers to the on-board network, hence the need for greater modularity in the on-board network.

[0011] There is a need to address the above drawback.

[0012] The invention aims to meet this need and achieves this, according to one of its aspects, using an on-board network for an electric vehicle, comprising:

[0013] - a first sub-network comprising a first electrical energy storage unit at a first direct voltage, a direct / alternating voltage converter, and in particular the electrical stator winding of a rotating electrical machine,

[0014] - a second sub-network comprising a second electrical energy storage unit at a second direct voltage, and capable of electrically supplying electrical consumers whose nominal voltage is equal to the second direct voltage,

[0015] - a third sub-network at a third direct voltage, capable of supplying electrical consumers whose nominal voltage is equal to the third direct voltage, the on-board network comprising:

[0016] - a first DC / DC converter for converting the first DC voltage into the second DC voltage and vice versa, and

[0017] - a second DC / DC converter to convert the second DC voltage into the third DC voltage and vice versa.

[0018] The invention thus makes it possible to benefit from an on-board network with three voltage levels. The invention also makes it possible to have at least two electrical energy storage units in the on-board network. Depending on the choice of the equipment manufacturer or constructor, electrical consumers with a nominal voltage equal to the second DC voltage or with a nominal voltage equal to the third DC voltage can be installed, without it being necessary to modify the structure of the on-board network.

[0019] This provides a standardized on-board network architecture that is compatible with the gradual or non-progressive integration of electrical consumers with different nominal voltages. This results in cost savings and increased industrial flexibility. Furthermore, the amount of cabling on board the vehicle can be reduced, resulting in weight savings as well.

[0020] The first DC voltage may be higher than the second DC voltage, and the second DC voltage may be higher than the third DC voltage. The first DC voltage is, for example, 400V or 800V, or even higher. The first DC voltage may, for example, be any value between 400V and 800V. The second DC voltage may, for example, be 48V or have another value lower than or equal to 60V, in accordance with ISO 64693.

[0021] The third direct voltage is for example equal to 12V, 14V, 16V, or even 18V.

[0022] The network may comprise a distribution module integrating the second DC / DC converter, this distribution module receiving the second direct voltage from the second electrical energy storage unit and / or from the first DC / DC converter. Such a distribution module may constitute an entry point for the part of the on-board network in which the electrical consumers are located.

[0023] This distribution module is presented, for example, in the form of a closed box. Other shapes are possible. Due to the presence within the distribution module of the second DC / DC converter, the distribution module can delimit a part of the second sub-network and a part of the third sub-network.

[0024] The distribution module may comprise means for interrupting the current, for example fuses. "Fuse" must here be understood functionally, including in particular contactors or power distribution semiconductors. This protects the electrical consumers from an electrical incident occurring in the first sub-network, or protects the first sub-network from an electrical incident occurring at one of the electrical consumers. The distribution module may comprise:

[0025] - a first input receiving the second direct voltage via a connection from the second electrical energy storage unit, and

[0026] - a second input receiving the second DC voltage via a connection from the first DC / DC converter, said connections being independent of each other.

[0027] This provides redundancy in the power supply to the distribution module, and therefore to the electrical consumers, at a second DC voltage.

[0028] In all of the above, the third DC voltage may never be directly obtained using the first DC voltage, and vice versa. That is, the conversion between the first DC voltage and the third DC voltage may always require an intermediate conversion to the second DC voltage.

[0029] Alternatively, the third DC voltage may be obtained in part directly using the first DC voltage, an additional DC / DC converter then being provided to enable this direct conversion of electrical energy between the first DC voltage and the third DC voltage. The distribution module may comprise at least one first output distributing the second DC voltage and at least one second output distributing the third DC voltage. It may thus be possible for all or part of the electrical consumers to be supplied by the second DC voltage or by the third DC voltage.Thus, taking into account the technological evolution of certain electrical consumers causing their nominal voltage to change from the third to the second direct voltage, the network architecture can be maintained while allowing an electrical consumer at the third direct voltage to be replaced by the same electrical consumer at the second direct voltage, and vice versa where appropriate.

[0030] The network may include at least one of:

[0031] - a set of vehicle air conditioning consumers as mentioned above,

[0032] - a set of vehicle lighting or vehicle window wiping consumers as mentioned above,

[0033] - a set of vehicle propulsion consumers as mentioned above, and

[0034] - a set of vehicle driving assistance consumers as mentioned above, and

[0035] - a set of consumers for the proper functioning of the vehicle interior.

[0036] The distribution module may include a centralized control unit, controlling the operation of these assemblies. This centralized control unit may be responsible for monitoring the proper functioning of the various assemblies, in particular to detect any failures. Through this centralized system, it is possible to achieve intelligent power distribution in the network in order to reduce the criticality of a feared event.

[0037] This control unit is, for example, the only control unit of the on-board network for the operation of the assemblies, so that the operation of each of these assemblies is solely controlled by the centralized control unit of the distribution module. Alternatively, the operation of each of these assemblies is, for example, controlled by a control unit that may be specific to said assembly. This specific control unit may interact with the centralized control unit.

[0038] The network may comprise a control link being for example a CAN or Ethernet type bus connecting the distribution module and each of said sets of electrical consumers. In this case, the control bus may be connected from the distribution module to each control unit. In all of the above, the first output(s) may be in the form of a DC voltage bus and supply at least one of:

[0039] - at least one consumer from the set of air conditioning consumers in the vehicle,

[0040] - at least one consumer from the set of vehicle lighting or vehicle window wiping consumers,

[0041] - at least one consumer from the set of propulsion consumers of the vehicle,

[0042] - at least one consumer from the set of vehicle driving assistance consumers, and

[0043] - at least one consumer from the set of consumers for the proper functioning of the vehicle interior.

[0044] The second output(s) can be in the form of a DC voltage bus and supply at least one of:

[0045] - at least one consumer from the set of air conditioning consumers of a vehicle,

[0046] - at least one consumer from the set of vehicle lighting or vehicle window wiping consumers,

[0047] - at least one consumer from the set of propulsion consumers of the vehicle,

[0048] - at least one consumer from the set of vehicle driving assistance consumers, and

[0049] - at least one consumer from the set of consumers for the proper functioning of the vehicle interior.

[0050] Within the same set of electrical consumers, all consumers can be supplied only by one type of direct voltage, namely exclusively by the second direct voltage or exclusively by the third direct voltage.

[0051] Alternatively, different DC voltages can be used within at least one of the sets of electrical consumers. Thus, some consumers in the set are, for example, supplied by the second DC voltage and other consumers in this set are supplied by the third voltage.

[0052] In a variant, at least one of the sets of electrical consumers can be powered by the first direct voltage, in addition to the second direct voltage and / or the third direct voltage. More generally, at least one of the sets of electrical consumers can be powered by two different direct voltages, among the first direct voltage, the second direct voltage and the third direct voltage.

[0053] Where appropriate, some electrical consumers, particularly for safety reasons, may benefit from redundancy in their power supply. This redundancy may mean that they have two separate connections for the same type of DC voltage, or that they have two separate connections, one to the second DC voltage, the other to the third DC voltage.

[0054] In all of the above, the distribution module may comprise an electronic card and each set of consumers may be connected to a card specific to said set of consumers and axially overlapping the electronic card of the distribution module. The electronic card of the distribution module has, for example, a portion at the second DC voltage and a portion at the third DC voltage. In this case, when each set of electrical consumers is powered by only one of the second electrical voltage and the third electrical voltage, the card of this set may be axially overlapping the portion of the electronic card of the distribution module corresponding to this electrical voltage. When several sets are powered by the same electrical voltage, their cards may be stacked above the portion of the electronic card of the distribution module corresponding to this voltage.

[0055] Alternatively, the cards of the different sets powered by the same direct voltage are not necessarily axially overlapped, being for example stacked in an offset manner two by two.

[0056] In all of the above, the third sub-network can be unique and exclusively connected to the rest of the on-board network via the second DC / DC converter.

[0057] Alternatively, in all of the above, at least one of said sets of consumers is exclusively powered by a first output of the distribution module and this set of consumers comprises another second DC / DC converter making it possible to convert the second DC voltage into the third DC voltage and vice versa, so as to be able to selectively power all or part of the consumers of this set by the second DC voltage or by the third DC voltage.

[0058] In all of the above, the third subnetwork may or may not include a third electrical energy storage unit at the third DC voltage. In all of the above, the on-board network may route, on the same electrical cable, the power signal, but also the control signal. This sharing is for example according to the Power over Ethernet technology, defined by the IEEE 802.3af standard. The routing on the same cable of the power signal and the control signal is done in particular in the second subnetwork and in the third subnetwork, or even exclusively in the second subnetwork and in the third subnetwork.

[0059] In all of the above, the rotating electrical machine can be a synchronous machine with magnets or a wound rotor. Alternatively, it can be an asynchronous machine, for example.

[0060] The electrical machine is, for example, a three-phase synchronous machine or a synchronous machine whose stator electrical winding defines a double three-phase system. More generally, the stator is polyphase. The stator electrical winding is, for example, formed by wires or by conductive bars connected to each other.

[0061] The first sub-network comprises, for example, an exchange interface for charging the first electrical energy storage unit. This interface allows, for example, wired or wireless charging. In the latter case, the inductive exchange of electrical energy can take place at a frequency of 3 kHz or 85 kHz.

[0062] The invention may be better understood by reading the following example of its implementation and by examining the attached drawing in which:

[0063] - [Fig.l] schematically represents an on-board network of an electric vehicle according to an exemplary implementation of the invention, and

[0064] - [Fig.2] schematically represents an example of a distribution module of the on-board network of figure 1.

[0065] Figure 1 shows an on-board network 1 of an electric vehicle according to an exemplary implementation of the invention. This electric vehicle is here without a thermal engine and is propelled by a rotating electrical machine which may be a permanent magnet synchronous machine, a wound rotor synchronous machine, or an asynchronous machine for example. This rotating electrical machine provides for example a power of between 100 kW and 200 kW.

[0066] The on-board network 1 comprises, in the example considered, a first sub-network 2 comprising a first electrical energy storage unit 3, a direct / alternating voltage converter 4, and the electrical stator winding (not shown) of the aforementioned rotating electrical propulsion machine and powered by the first electrical energy storage unit 3 through another direct / alternating voltage converter (not shown). The first electrical energy storage unit 3 has, for example, a nominal voltage of the order of 400V or 800V, and this nominal voltage will subsequently be called “first direct voltage”. The first sub-network 2 also comprises, in the example considered, an exchange interface 6 for charging the first electrical energy storage unit 3.This exchange interface 6 allows for example a wired charge or a wireless charge of the first electrical energy storage unit 3 from an electrical network 5 which can be three-phase alternating, single-phase alternating, or direct. In the present case, the electrical network is alternating and the charging of the first electrical energy storage unit 3 is done through the direct / alternating converter 4. In the case of a wireless charge, the exchange of electrical energy by inductive means can be done at a frequency of 3 kHz or 85 kHz. The first sub-network 2 also comprises in the example considered a distribution component 9 also called “Power Distribution Unit” in English.

[0067] In the example shown, two first DC / DC converters 10 are provided to reversibly convert the first DC voltage into a second DC voltage, but in a variant not shown, a single first DC / DC converter 10 could be provided.

[0068] The on-board network 1 further comprises a second sub-network 11 comprising a second electrical energy storage unit 12. The second electrical energy storage unit has, for example, a nominal voltage of 48V. The nominal voltage of the second electrical energy storage unit 12 is the aforementioned second DC voltage. The second sub-network 11 is capable, as will be seen later, of supplying electrical consumers of the on-board network.

[0069] These electrical consumers are distributed here according to sets.

[0070] It can be seen in Figure 1 that the on-board network 1 comprises, for example, a set 20 of vehicle air conditioning consumers, which comprises, in the example described: valves 21, a collector 22, a fan 23, water pumps 24, an air conditioning compressor 25, and a high-voltage heating module on the water loop 26.

[0071] The on-board network 1 also comprises, in the example described, a set 30 of vehicle lighting or vehicle window wiping consumers, which here comprises front headlights 31, rear headlights 32, front windscreen wipers 33, rear windscreen wipers 34, a front defrosting module 35 and a rear defrosting module 36. As can be seen in FIG. 1, the headlights 31 and 32 benefit in this example from a redundant electrical supply.

[0072] The on-board network 1 also comprises, in the example described, a set 40 of vehicle propulsion consumers, this set 40 here comprising a wired steering control 41, a wired braking control 42, an active suspension 43. It can be seen in FIG. 1 that the steering control 41 and the braking control 42 benefit in the example considered from a redundancy of electrical power supply.

[0073] Still in the example considered, the on-board network 1 also includes a set 50 of consumers for driving assistance, called "ADAS" in English. These electrical consumers of the set 50 benefit in the example considered from a redundancy of electrical supply.

[0074] Still in the example considered, the on-board network 1 comprises a set 60 of consumers for the proper functioning of the passenger compartment of the vehicle, being for example chosen from all or part of the following consumers: door window regulator 61, door lighting 62, seat heating panel 63, trunk opening actuator 64, hood opening actuator 65, electrical socket 66 in the trunk.

[0075] Each of the sets 20, 30, 40, 50 and 60 is here controlled by a control unit.

[0076] The on-board network comprises in the example described a distribution module 70. This distribution module 70 which is for example in the form of a box can integrate a second DC / DC converter 71. This distribution module 70 can here have two inputs 72 and 73, each of these inputs receiving the second DC voltage. The input 72 thus receives the second DC voltage from the second electrical energy storage unit 12, while the input 73 receives the second DC voltage from the first DC / DC converter 10. The distribution module integrates for example fuses not shown, making it possible to interrupt the current between the second sub-network 11 and a third sub-network 80 which will now be described. The third sub-network 80 here has a third voltage converted by the second DC / DC converter 71 from the second DC voltage, and vice versa.

[0077] The distribution module 70 comprises in the example described:

[0078] - at least one first output 74 distributing the second direct voltage, this first output 74 being in the example considered a voltage bus belonging to the second sub-network 11, and

[0079] - at least one second output 75 distributing the third direct voltage, this second output 75 being in the example considered a voltage bus belonging to the third sub-network 80.

[0080] In the exemplary embodiment of the distribution module shown in Figure 2, but in a non-limiting manner, two first outputs 74 and a second output 75 are provided. It can also be seen in Figures 1 and 2 that the control of the electrical consumers of the different assemblies can be carried out from the distribution module 70 by means of a control bus 78. In the example considered, the control bus 78 is connected from the distribution module 70 to each control unit of a set of electrical consumers.

[0081] As can be seen in Figure 1, for each of the sets 20, 30, 40 and 50 of consumers, the second voltage via a voltage bus 74 or the third voltage via a voltage bus 75 are available to supply all or part of the electrical consumers of said set. It is thus possible to modify, depending on the choice of the voltage bus to which the consumers are connected, the composition of the second sub-network 11 and the third sub-network 80. In other words, the modification of the composition of the second sub-network 11 and the third sub-network 80 does not require the modification of the voltage buses 74 or 75, but only the choice of the bus 74 or 75 to which the electrical consumers are connected.

[0082] It can also be seen in Figure 1 that the invention can allow all or part of the electrical consumers of the assemblies 20 and 40 to be additionally potentially supplied using the first DC voltage, using a voltage bus 79 external to the distribution module 70 in Figure 1. As a variant, this voltage bus 79 at the first DC voltage making it possible to supply electrical consumers of the assemblies 20 and 40 could pass through the distribution module 70.

[0083] The second DC / DC converter 71 arranged in the distribution module is not necessarily unique. As shown in FIG. 1, the set 60 of electrical consumers for the proper functioning of the living area receives, for example, from the distribution module only a bus 74 at the second DC voltage, and the electronic card associated with this set 60 carries another second DC / DC converter 71, making it possible to convert the second DC voltage into the third DC voltage, and vice versa.

[0084] Figure 2 represents an embodiment of the distribution module when each of the assemblies 20 to 50 has its electrical consumers supplied by only a single DC voltage. It can be seen that the distribution module 70 has an electronic card 81 having a part 82 at the second DC voltage, and a part 83 at the third DC voltage. The electronic card 84 associated with a set of electrical consumers supplied only by the second electrical voltage is then arranged above the part 82, while the electronic card 84 associated with a set of electrical consumers supplied only at the third electrical voltage is then arranged above the part 83. Several electronic cards 84 are for example stacked above the part 82 and supplied by the same bus 88 internal to the distribution module 70 and at the second DC voltage.If necessary, several buses 88 at the second direct voltage are provided in parallel in the distribution module 70.

[0085] Several electronic cards 84 can similarly be stacked above the part 83 and powered by the same bus 89 internal to the distribution module 70 and to the third direct voltage.

[0086] The invention is not limited to the examples which have just been described.

[0087] The invention also applies to a plug-in hybrid vehicle.

Claims

Claims 1. On-board network (1) for electric or hybrid vehicle, comprising: - a first sub-network (2) comprising a first electrical energy storage unit (3) at a first direct voltage, a direct / alternating voltage converter (4), and in particular the electrical stator winding of a rotating electrical machine, - a second sub-network (11) comprising a second electrical energy storage unit (12) at a second direct voltage, and capable of electrically supplying electrical consumers whose nominal voltage is equal to the second direct voltage, - a third sub-network (80) at a third direct voltage, capable of electrically supplying electrical consumers whose nominal voltage is equal to the third direct voltage, the on-board network comprising: - a first DC / DC converter (10) for converting the first DC voltage into the second DC voltage and vice versa, and - a second DC / DC converter (71) for converting the second DC voltage into the third DC voltage and vice versa the network (1) comprising at least one: - a set (20) of electrical air conditioning consumers of a vehicle, - a set (30) of electrical consumers for vehicle lighting or vehicle window wiping, - a set (40) of electrical consumers for vehicle propulsion, - a set (50) of electrical consumers to assist in driving the vehicle, and - a set (60) of electrical consumers for the proper functioning of the passenger compartment of the vehicle, and at least one of the sets of electrical consumers (20, 30, 40, 50, 60) being supplied by two different direct voltages from among: the first direct voltage, the second direct voltage, and the third direct voltage.

2. Voltage network according to claim 1, comprising a distribution module (70) integrating the second DC / DC converter (71), this distribution module (70) receiving the second direct voltage from the second electrical energy storage unit (12) and / or from the first DC / DC converter (10).

3. Voltage network according to claim 2, the distribution module (70) comprising: - a first input (72) receiving the second direct voltage via a connection from the second electrical energy storage unit (12), and - a second input (73) receiving the second direct voltage via a connection from the first DC / DC converter (10), said connections being independent of each other.

4. Voltage network according to claim 2 or 3, the distribution module (70) comprising means for interrupting the current.

5. Network according to any one of claims 2 to 4, the distribution module (70) comprising at least one first output (74) distributing the second direct voltage and at least one second output (75) distributing the third direct voltage.

6. Network according to claim 5, the first output(s) (74) being in the form of a direct voltage bus and supplying at least one: - at least one consumer of the set (20) of air conditioning consumers of a vehicle, - at least one consumer of the set (30) of vehicle lighting or vehicle window wiping consumers, - at least one consumer of the set (40) of propulsion consumers of the vehicle, - at least one consumer (50) of the set of vehicle driving assistance consumers, and - at least one consumer (60) of the set of consumers for the proper functioning of the vehicle interior.

7. Network according to claim 5 or 6, the second output(s) (75) being in the form of a direct voltage bus and supplying at least one: - at least one consumer of the set (20) of air conditioning consumers of a vehicle, - at least one consumer of the set (30) of vehicle lighting or vehicle window wiping consumers, - at least one consumer of the set (40) of propulsion consumers of the vehicle, - at least one consumer of the set (50) of vehicle driving assistance consumers, and - at least one consumer from the set (60) of consumers for the proper functioning of the vehicle interior.

8. Network according to any one of claims 2 to 7, the distribution module (70) comprising an electronic card (81) and each set of consumers being connected to a card (84) specific to said set of consumers and axially overlapping the electronic card (81) of the distribution module (70).

9. Network according to any one of claims 2 to 8, the distribution module (70) comprising a centralized control unit, controlling the operation of the sets (20, 30, 40, 50, 60).

10. Network according to any one of the preceding claims, the third sub-network (80) being unique and exclusively connected to the rest of the on-board network via the second DC / DC converter (71).

11. Network according to claim 5 and any one of the preceding claims, at least one of said sets (60) of consumers being exclusively supplied by a first output (74) of the distribution module (70), and comprising another second DC / DC converter (71) making it possible to convert the second direct voltage into the third direct voltage and vice versa, so as to be able to selectively supply all or part of the consumers of this set (60) by the second direct voltage or by the third direct voltage.

Images