FR3037733A1 - ELECTRICAL POWER SUPPLY NETWORK FOR THE EQUIPMENT OF A MOTOR VEHICLE WITH DOUBLE SUB-ARRAYS AND USE THEREOF - Google Patents

Abstract

The electrical network (14) according to the invention is of the type of those comprising a first electrical sub-network (15) with a predetermined first nominal voltage (V1) with respect to a reference potential comprising a first electrical energy store ( 21), and a second electrical sub-network (16) at a second predetermined nominal voltage (V2) with respect to the reference potential comprising a second electrical energy store (22). According to the invention, the first sub-network is connected to a first terminal (19) of a double rotating electrical machine (17) connected by a ground terminal (18) to the reference potential, and the second sub-network is connected to a second terminal (20) of the double rotating electrical machine. According to another characteristic, the double rotating electrical machine is a reversible double-voltage motor.

Description

1 ELECTRICAL POWER SUPPLY NETWORK OF EQUIPMENT OF A MOTOR VEHICLE WITH DOUBLE SUB-RESALS AND USE THEREOF TECHNICAL FIELD OF THE INVENTION

The invention relates to an electrical supply network for the equipment of a motor vehicle with double sub-networks, as well as its use in a vehicle. BACKGROUND ART OF THE INVENTION.

When a starter is energized to start the vehicle's combustion engine, a large current draw occurs which is close to the short-circuit current level of the starter, ie a current of the starter motor. order of 1000 amperes. This current draw when the starter is energized then decreases in intensity as the starter armature, corresponding to the rotor of the machine, rises in speed. The activation of other high power components, for example an electric supercharger, transiently produces a strong current draw on the vehicle electrical network. At this peak of current corresponds a consequent fall in the voltage on the on-board network, which may lead to cuts or malfunctions of the other consumer devices of the vehicle. In the prior art, solutions have been proposed to the problem set forth above. A known solution of the inventive entity is based on the use of electronic step-up converters in order to avoid a low voltage level on the on-board network. A disadvantage of these converters lies in the substantial costs they introduce. It is also known to use two sub-networks, one for powering the high power components, and the other for the power supply of the safety or comfort components of the vehicle, for example the headlights of the vehicle, to ensure their operation at any time for the safety and comfort of passengers. A power supply network with double sub-networks of this type is described in international patent application WO2014053780 from VALEO SYSTEMES DE CONTROLE MOTEUR. A first subnet comprising a first electrical energy store 3037733 - 2 - is powered by an alternator, and a second subnet comprises a second electrical energy store that is loaded from the first network by a continuous converter. - continued. Two switches make it possible to connect the two subnetworks to each other, or to isolate a high power component, such as the starter, from the subnet to which sensitive components are connected. This architecture, which also gives any satisfaction, however has disadvantages: - at least one of the two switches has critical design constraints (maximum current, operating point ...); Use of a DC-DC converter between the two sub-networks. GENERAL DESCRIPTION OF THE INVENTION The present invention therefore aims at overcoming the disadvantages of the known prior art solution for isolating sensitive loads from disturbances generated by power components, while limiting the complexity of the architecture implemented. artwork. The power supply network of the equipment of a motor vehicle with double sub-networks in question, is of the type of those comprising a first electrical sub-network at a predetermined first nominal voltage with respect to a reference potential comprising a first electrical energy store, and a second electrical sub-network at a second nominal voltage predetermined with respect to this same reference potential comprising a second storage of electrical energy. According to the invention, the first sub-network is connected to a first terminal 25 of a dual rotating electrical machine connected by a ground terminal to the reference potential, and the second sub-network is connected to a second terminal of the machine. double rotating electric. In a first embodiment of the invention, this double rotating electrical machine is a reversible double-voltage motor. In a second embodiment of the invention, this dual rotating electrical machine is a dual voltage alternator. According to the invention, in this second embodiment of the invention, a starter is connected to the first sub-network. In either embodiment, according to the invention, the first rated voltage and the second rated voltage are substantially equal to a predetermined standard voltage. According to the invention, a normally closed electromagnetic power relay is connected between the first terminal and the second terminal of the dual rotating electrical machine. According to the invention again, the standard voltage is 12 V, and preferably the first electrical energy store is of the lead-acid type, the first nominal voltage being about 12.8 V, and the second storage of The electrical energy is of lithium-ion type, the second nominal voltage being about 14.4 V. A normally closed semiconductor safety switch is arranged according to the invention in series with the second electrical energy storage. The invention also relates to a use of the power supply network of the equipment of a motor vehicle with double sub-networks in the first embodiment described above for: isolating sensitive electrical loads connected to the second sub-network of Disturbances generated by a power load connection to the first sub-network; and - transferring electrical energy between the first storer of electrical energy and the second storer of electrical energy and thereby controlling the distribution of electrical power taken or supplied to the first and second sub-arrays. In the second embodiment of the invention, the power supply network of the equipment of a motor vehicle with double sub-networks will also be used to: isolate sensitive electric charges connected to the second sub-network of generated disturbances by a power charge connection to the first subnetwork; and - transferring electrical energy between the first storer of electrical energy and the second storer of electrical energy and thus controlling the distribution of the electrical power supplied to the first and second sub-arrays. These few specifications of the invention will have made it obvious to one skilled in the art to overcome the disadvantages of the only solution known to date which made it possible to ensure the operation at any time of sensitive electrical charges. The detailed specifications of the invention are given in the following description in conjunction with the accompanying drawings. It should be noted that these drawings serve no purpose other than to illustrate the text of the description and in no way constitute a limitation on the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram of a power supply network 5 of the equipment of a motor vehicle with double sub-networks known from the state of the art. Figure 2 is a block diagram of a power supply network of the equipment of a motor vehicle with double sub-networks according to the invention. 3a, 3b, 3c and 3d illustrate different modes of operation of the power supply network of the equipment of a motor vehicle with double sub-networks according to the invention, respectively during a parking of the vehicle, during a restart or torque assistance of the engine, idling of the engine or constant speed of the vehicle, during a regenerative braking. DESCRIPTION OF PARTICULAR EMBODIMENTS OF THE INVENTION The electrical power supply network 1 for the equipment of a double sub-car vehicle known from the state of the art shown in FIG. 1 comprises: a first electrical sub-network 2 connected to a first battery 3 lead-acid type charged by an alternator 4 and operating at a first nominal voltage of about 12 V with respect to a mass 5; a second electrical sub-network 6 connected to a super-capacitor 7 or a second battery 7 of lithium-ion type.

A DC-DC converter 8 charges the super-capacitor 7 or the second battery 7 from the first sub-array 2 and adapts the voltage levels. In this electrical network 1 of the state of the art, the security and comfort components 9 are connected classically in parallel with the first battery 3 and the alternator 4 on the first sub-network 2. The high power components 10 , 11 are connected in parallel with the super-capacitor 7, in particular the electric supercharger 10 and the starter 11. A first switch 12 and a second switch 13 make it possible to vary the operating modes of the second sub-network 6. 3037733 When the first switch 12 is open and the second switch 13 is closed, the electric compressor 10 and the starter 11 are powered by the super-capacitor 7 and isolated from the first sub-network 2. The compressor 10 and the starter 11 can also be powered by the first sub-network 2 (the first and second switches 12, 13 are closed). Alternatively, the electric compressor 10 is powered by the super-capacitor 7, while the starter is powered by the first sub-network 2 (first switch 12 closed, second switch 13 open). In the power supply network 14 for the equipment of a vehicle with a double sub-array according to the invention shown in FIG. 2, the management of the different modes of operation of the first and second sub-networks 15, 16 is simplified. by virtue of the use of a double rotating electrical machine 17. This machine 17 is connected by a ground terminal 18 to a common ground 5 of the first and second sub-networks 15, 16, on the one hand, to the first subnet 15 by a first terminal 19 and second subarray 16 by a second terminal 20, on the other hand. The first sub-network 15, operating at a first predetermined nominal voltage V1 with respect to the common ground 5, comprises a first electrical energy store 21. The second sub-array 16, operating at a second predetermined nominal voltage V2 by In the preferred embodiments of the invention, the first storage unit 21 is a first conventional lead-acid battery having a first voltage in charge of the same. about 12.8 V. The second energy store 22 is a second lithium-ion battery having a second load voltage of about 14.4V. In this way, the first and second nominal voltages V1, V2 of first 30 and second sub-networks 15, 16 are substantially equal to a standard voltage V of about 12 V of operation of conventional equipment of a motor vehicle. In a first preferred embodiment of the invention, the double rotating electrical machine 17 is a reversible double-voltage motor.

This motor 17 comprises a stator comprising two three-phase windings. Each of the windings is connected to a reversible dc direct current converter outputly connected between the ground terminal 18 and each of the first and second terminals 19, 20 of the motor 17. That is to say, this motor 17 is equivalent to a reversible synchronous subnetwork machine 15, 16, 5 that can operate in motor mode or in generator mode. In a second preferred embodiment of the invention, the dual rotating electrical machine 17 is a dual voltage alternator. This alternator 17 comprises a stator comprising two three-phase windings. Each of the windings is connected to a three-phase rectifier circuit connected at the output between the ground terminal 18 and each of the first and second terminals 19, 20 of the alternator 17. In this second preferred embodiment, a starter 23 is connected in parallel on the first battery 21 (lead acid). In the first and second embodiments, a normally closed electromagnetic power relay 24 is connected between the first and second terminals 19, 20 of the rotating electrical machine 17. For reasons of compliance with standards, a semiconductor safety switch Normally closed is connected in series with the second battery 22 (li-ion).

Figures 3a, 3b, 3c and 3d illustrate the possible use of the power grid 14 in a vehicle. FIG. 3a corresponds to a first mode of operation of the electrical network 14 during parking of the vehicle, both in the first preferred embodiment of the invention and in the second: the electromagnetic power relay 24 is closed and connects between they the first and second sub-networks 15, 16 which can provide energy 26, 27 in parallel. Figure 3b corresponds to a second mode of operation of the electrical network 14, exclusively in the first preferred embodiment of the invention, during the restart or assistance in torque of the engine. In this case, the electromagnetic power relay 24 remains open and different energy management strategies are possible: - for restarting or assisting in torque, the energy 29, 30 necessary for the production of a driving torque 28 is provided by both the first lead battery 21 and the second lithium battery 22, with a determined choice of a power level 29, 30 for each battery 21, 22; For the restart, the energy 29 comes only from the first lead-acid battery 21 and another energy 27 is supplied to the sensitive components connected to the second sub-network 16 by a half of the reversible double-voltage motor 17 operating in generator mode 30; 5 - for assistance in torque, energy 30 comes only from the second battery 22 lithium. Figure 3c corresponds to a third mode of operation of the electrical network 14, exclusively also in the first preferred embodiment of the invention, at idle of the engine or constant speed of the vehicle.

No torque is taken from the heat engine, but the reversible dual voltage motor 17 transfers energy 31, 32 between the first and second sub-networks 15, 16. In the third mode of operation shown in FIG. 3c, energy 31 from the second sub-array 16 is supplied to the first sub-array 15 by means of the reversible double-voltage motor 17 operating as a dc-dc electromechanical converter: the synchronous machine connected to the second subsystem network 16 operates in motor mode and virtually drives the other synchronous machine connected to the first network 15 operating in generator mode.

The transferred energy 32 can be used both to charge the first battery 11 and to feed the loads of the first sub-array 15. FIG. 3d corresponds to a fourth mode of operation of the electrical network 14, both in the first preferred embodiment of the invention that in the second, during a regenerative braking phase of the vehicle in which a resistive torque 34 is taken from the shaft of the engine driven by the wheels of the vehicle to provide energy 32, 35 to both the first and second sub-arrays 15, 16 (with a suitable level) for charging the first lead battery 21 and charging the second lithium battery 22. To do this, in the first preferred embodiment of the invention, each synchronous machine of the reversible dual-voltage motor 17 operates in generator mode. The advantages of this architecture are: - no specific DC-DC converter 8 and no semiconductor switch 12 between the first and second sub-networks 15, 16; a nominal level of guaranteed voltage for supplying the sensitive electrical loads connected to the second sub-network during very demanding power phases (start-up, restart, over-power, etc.); a balancing of the currents between the first and second sub-networks 15, 16 in all the phases of high power operation; An embodiment of a DC-DC conversion function (in the first embodiment of the invention) for providing an additional energy exchange 31, 32 between the first and second sub-networks 15, 16; an assurance of optimized management of the first and second batteries 21, 22 and of a complete adaptation of a distribution of the auxiliary loads to the needs; 10 - possible use in any type of vehicle with standard "12 V" electrical equipment. It goes without saying that the invention is not limited to the only preferred embodiments described above. The equipment mentioned are also only non-limiting examples: any sensitive load would benefit from isolation of any vehicle equipment constituting an inductive or capacitive load likely to produce a strong current draw at power on by the power grid. according to the invention. The second battery 22 mentioned is a lithium-ion type battery of iron-phosphate technology. A battery 22 of yttrium doped iron-phosphate technology (LiFeYPO4) could equally well be used in the second sub-network 16 of the electrical network 14 according to the invention, as well as batteries of other technologies such as lithium cobalt oxide (LiCoO 2), lithium manganese oxide (LiMn 2 O 4), lithium nickel manganese cobalt oxide (LiNiMnCoO 2), lithium nickel manganese aluminum oxide (LiNiMnAlO 2), lithium titanate (Li4Ti5012, with five elements in series). The invention therefore embraces all possible variants of embodiment within the scope of the subject of the claims below.

Claims (9)

CLAIMS1) Electrical network (1, 14) for supplying the equipment of a motor vehicle with double sub-networks (2, 6, 15, 16) of the type comprising those having a first electrical sub-network (2, 15) to a first rated voltage (V1) predetermined with respect to a reference potential comprising a first electrical energy store (3, 21), and a second electrical subnet (6, 16) at a second predetermined nominal voltage (V2) with respect to said reference potential comprising a second electrical energy store (7, 22), characterized in that said first sub-network (15) is connected to a first terminal (19) of a dual rotating electrical machine ( 17) connected by a ground terminal (18) to said reference potential, and in that said second sub-array (16) is connected to a second terminal (20) of said dual rotating electrical machine (17). 15 2) Electrical power network (14) for powering the equipment of a motor vehicle with double sub-networks (15, 16) according to claim 1, characterized in that said double rotating electrical machine (17) is a reversible double voltage motor. . 20 3) Electrical network (14) for powering the equipment of a motor vehicle with double sub-networks (15, 16) according to claim 1, characterized in that said double rotating electrical machine (17) is a dual voltage alternator. 25 4) Electrical network (14) power supply equipment of a motor vehicle with dual sub-networks (15, 16) according to claim 3 above, characterized in that a starter (23) is connected to said first sub-network (15). 5) Electrical network (14) for supplying the equipment of a motor vehicle 30 with double sub-networks (15, 16) according to any one of the preceding claims 1 to 4, characterized in that an electromagnetic power relay (24) normally closed is connected between said first terminal (19) and said second terminal (20). 3037733 - 10 - 6) Electrical network (14) for powering the equipment of a motor vehicle with double sub-networks according to the preceding claim 5, characterized in that said first storer of electrical energy (21) is of lead-acid type, said first nominal voltage (V1) being about 12.8 V, and said second electrical energy storage (22) is of the lithium-ion type, said second nominal voltage (V2) being about 14.4 V. 7. An electrical power supply network (14) for the equipment of a double sub-motor vehicle (15, 16) according to the preceding claim 6, characterized in that a normally closed semiconductor safety switch (25) is arranged in series with said second electrical energy storage (22). 8) Using an electrical power supply network (14) for powering the equipment of a dual sub-motor vehicle (15, 16) according to the preceding claim 2 for: isolating sensitive electrical loads connected to said second sub-network; network (16) of disturbances generated by a power load connection (23) to said first sub-network (15); and - transferring electrical energy (31, 32) between said first electrical energy store (21) and said second electrical energy store (22) and thereby controlling the distribution of electrical power taken or supplied to said first and second subnets (15, 16). 9) Using an electrical power supply network (14) for powering the equipment of a dual sub-network vehicle (15, 16) according to the preceding claim 4 for: isolating sensitive electrical loads connected to said second sub-network; network (16) of disturbances generated by a power load connection (23) to said first sub-network (15); and transferring electrical energy (31, 32) between said first electrical energy storage (21) and said second electrical energy storage (22) and thereby controlling the distribution of electric power supplied to said first and second sub-electrical energy networks (15, 16). 35