BATTERY-POWERED ELECTRIC MOTOR VEHICLE WITH A RANGE EXTENSION DEVICE

Abstract

The invention relates to an electric motor vehicle (1000) comprising at least one battery pack (2000) for powering an electric traction motor, said battery pack (2000) being housed under a floor or trunk of said electric motor vehicle (1000), wherein said electric motor vehicle (1000) comprises a range-extending device comprising at least one IRReGT cycle turbomachine (6000) comprising a turbogenerator (100) with energy recovery and intercooling, supplied by a fuel tank (7000), and arranged for recharging said battery pack (2000). Figure 10

Description

Title of the invention: BATTERY-POWERED ELECTRIC MOTOR VEHICLE COMPRISING A RANGE EXTENSION DEVICE

[0001] The invention relates to an electric motor vehicle comprising at least one battery pack for powering an electric traction motor, said at least one battery pack being housed under a floor or under a trunk that said electric motor vehicle comprises.

[0002] The invention relates to the field of battery-electric motor vehicles and the energy management of these vehicles.

[0003] The autonomy of battery electric vehicles is a constant concern for manufacturers.

[0004] Battery vehicles are limited in their use by a high cost, in particular because of the cost of the batteries proportional to their capacity, by a low autonomy (because of the energy density of the batteries compared to the energy density of a fuel), by the mass of the vehicle (especially because of the mass of the battery), and by the duration of recharging of the batteries.

[0005] The objective of the present invention is to remedy these drawbacks by proposing to equip such an electric or hybrid battery vehicle with a range extension device.

[0006] A good solution is to realize such a range extension device on the basis of a turbogenerator. The proposed turbogenerator technology is very promising for replacing an internal combustion engine in highly electrified powertrains, particularly for electric vehicles. The objective is to hybridize an electric vehicle by adding a micro-turbine as a range extender or as a power unit. This technology offers various advantages: low emissions, low noise, absence of vibrations, drastic reduction in maintenance (limited to changing the oil filter), and the ability to operate with several types of fuel.

[0007] More particularly, the invention proposes to achieve the physical and mechanical integration of a thermodynamic cycle turbogenerator called IRReGT (Intercooled Recuperative Reheat Gas Turbine), i.e. a turbogenerator with recovery and intermediate cooling.

[0008] The hybridization of an electric vehicle by an energy converter operating with a fuel with high energy density is a good solution to overcome the problems of battery electric vehicles set out above.

[0009] However, the integration of a turbogenerator range extension device in an electric vehicle must take into account various constraints.

[0010] Mechanical integration is limited because the front part of the vehicle is generally occupied by the electric traction machine and its power electronics; the rear part of the vehicle generally includes a trunk, the volume of which must not be reduced. The under-chassis / floor part of the vehicle is generally occupied by the batteries.

[0011] The thermal integration of a thermal converter requires the installation of a heat evacuation system. In particular, it is necessary to add exchangers and to create a coupling to the existing thermal circuit.

[0012] The addition of a thermodynamic machine generates noise, which is not appreciated by the user of an electric vehicle.

[0013] A turbogenerator produces electrical energy that must be returned to the battery. The IRReGT thermodynamic cycle turbogenerator-based autonomy extension device has two electrical machines.

[0014] To achieve this objective, the invention proposes an electric motor vehicle comprising at least one battery pack for powering an electric traction motor, said at least one battery pack being housed under a floor or under a trunk that said electric motor vehicle comprises.

[0015] According to the invention, said electric motor vehicle comprises a range extension device which comprises at least one IRReGT cycle turbomachine comprising a turbogenerator with recovery and intermediate cooling and which is powered by a fuel tank and which is arranged for recharging said at least one battery pack with energy.

[0016] Thanks to the invention, it is possible to significantly increase the autonomy of the vehicle. The solution of a turbomachine dedicated to powering the batteries makes it possible to ensure the traction of the vehicle by the electric traction motor alone.

[0017] Advantageously, each said turbomachine that comprises said electric motor vehicle is housed under said floor or under said trunk, or both under said floor and said trunk.

[0018] Thus the habitable volumes dedicated to the user are unchanged. The floor or the trunk constitutes a sound insulation between each turbomachine and the occupants of the vehicle.

[0019] Advantageously, said turbomachine comprises a said turbogenerator which is a double-stage turbine with recovery and intermediate cooling.

[0020] This configuration allows for high efficiency and fuel economy.

[0021] Advantageously, said turbomachine comprises a said turbogenerator which comprises at least one air filter, a first electrified turbocompressor for a stage low pressure comprising a low pressure compressor, a low pressure turbine, and a first electric machine equipped with a first inverter, a second electrified turbocharger for a high pressure stage comprising a high pressure compressor, a high pressure turbine, and a second electric machine equipped with a second inverter, at least one heat recovery unit by heat exchange between the air and the exhaust gases, at least one intercooler exchanger, supplied with ambient air or water from a heat transfer circuit and arranged to cool the air between said low pressure compressor and said high pressure compressor.

[0022] Thus the two low pressure and high pressure stages can be arranged according to the available volume, and energy management is optimized.

[0023] Advantageously, at the outlet of said high pressure compressor, a said heat recuperator is inserted before the gases enter a first combustion chamber which is arranged to drive said high pressure turbine, and a second combustion chamber is inserted between said high pressure turbine and said low pressure turbine, and is arranged to drive said low pressure turbine.

[0024] Thus it is possible to separate the two combustion chambers necessary for supplying the two low pressure and high pressure turbines.

[0025] Advantageously, said intercooler exchanger is arranged to heat the passenger compartment of said electric motor vehicle.

[0026] This allows you to save a heating source for winter journeys.

[0027] Advantageously, said electric motor vehicle comprises electrical coupling means for powering said battery pack by said first inverter and by said second inverter.

[0028] It is thus possible to manage, as needed, the energy generated by the turbomachine.

[0029] Advantageously, said electric motor vehicle comprises a chassis arranged to directly carry said battery pack, said fuel tank, at least one heat recovery unit included in said at least one turbomachine, and a rear cross member supporting the rear axle of said electric motor vehicle.

[0030] This provides a versatile chassis, usable both for an all-electric vehicle and for a vehicle according to the invention where part of the batteries is replaced by at least one turbomachine.

[0031] Advantageously, said turbomachine is arranged on either side of said rear crossmember.

[0032] Thus the rear cross member supports well-distributed forces.

[0033] Advantageously, said electric motor vehicle comprises a chassis arranged to carry said battery pack or a lower structure carrying said turbomachine and said fuel tank.

[0034] This variant includes a lower structure simplifying assembly and maintenance.

[0035] The invention will be further detailed by the description of non-limiting embodiments, and on the basis of the appended figures illustrating variants of the invention, in which: - [Fig.l] schematically illustrates a motor vehicle according to the invention; - [Fig.2] schematically illustrates the architecture of a double turbogenerator IRReGT thermodynamic cycle stage, the low pressure stage and the high pressure stage being separated; - [Fig.3] schematically illustrates the architecture of a double-stage turbogenerator with IRReGT thermodynamic cycle, where the low-pressure stage and the high-pressure stage are on the same rotation axis; - [Fig.4] illustrates schematically, partially and in a view from below, the equipment of a vehicle according to the invention; - [Fig.5] illustrates, in part and in a view from below, the chassis of a vehicle according to the invention in a variant where the chassis and the rear cross member of the vehicle do not carry the battery pack or the components of the turbomachine. The battery and the components of the turbomachine are coupled to the chassis of the vehicle and not to the rear cross member; - [Fig.6] schematically illustrates, in perspective view from above, the energy storage means of a vehicle according to the invention, and the turbomachine which equips it; - [Fig.7] schematically illustrates, in perspective view from above, the tur bomachine of [Fig.6]; - [Fig.8] schematically illustrates, in side view, the elements represented in [Fig.6]; - [Fig.9] schematically illustrates, in top view, the elements represented in [Fig.6]; - [Fig. 10] schematically and partially illustrates, in a view from below, a vehicle according to the invention in the variant shown in [Fig.6] to [Fig.9].

[0036] [Fig.l] schematically illustrates a battery-powered electric motor vehicle, comprising a range extension device, according to the invention. Such an electric motor vehicle 1000 comprises at least one battery pack 2000 for powering an electric traction motor, this at least one battery pack 2000 being housed under a floor 4000 or under a trunk 5000 that this electric motor vehicle 1000 comprises.

[0037] According to the invention, this electric motor vehicle 1000 comprises a range extension device which comprises at least one turbomachine 6000 which is powered by a fuel tank 7000 and which is arranged for recharging in energy from this at least one 2000 battery pack. More particularly and not limited to, this 6000 turbomachine is IRReGT cycle and comprises at least one 100 turbo-generator with recovery and intermediate cooling.

[0038] Advantageously, each turbomachine 6000 that this electric motor vehicle 1000 comprises is housed under the floor 4000 or under the trunk 5000, or both under the floor 4000 and the trunk 5000.

[0039] More particularly, this range extension device comprises a two-stage turbo-generator, as a power unit for extending the range. In particular, in a particular, non-limiting variant, and preferred due to its good efficiency, at least one such turbomachine 6000 comprises a turbo-generator 100 (illustrated in [Fig.2]) which is a micro-turbine operating with a liquid fuel or a gas, with a double stage with recovery and intermediate cooling.

[0040] The invention relates both to the ab nihilo design of a battery-powered motor vehicle with increased autonomy, and to the modification of an existing battery-powered motor vehicle, by retaining only part of the battery pack, and removing the rest of the battery pack so as to install such a device for extending autonomy, comprising at least one turbogenerator.

[0041] A turbogenerator-type energy converter is advantageous as a range extender, particularly in hybrid vehicles. This converter operates in APU (Auxiliary Power Unit) mode, where its role is to recharge the batteries of an electric vehicle. It is thus mechanically decoupled from the powertrain and thus operates at its maximum efficiency point.

[0042] The innovation can advantageously be applied to an energy converter of the turbogenerator type with an "intercooled recuperative reheat gas turbine" (IRReGT) thermodynamic cycle, i.e. a turbogenerator with recovery and intermediate cooling. Compared to an RGT cycle (Recuperative Gas Turbine / Simple turbine cycle), the turbogenerator operates according to the IRReGT cycle, it is a double-stage machine making it possible to achieve a higher efficiency and a higher power density. If the RGT cycle (Recuperative gas turbine), also applicable to the invention, requires a single combustion chamber, the IRReGT cycle requires two combustion chambers, as seen in [Fig.2], and in [Fig.3], but its efficiency is much higher than that of an RGT cycle.

[0043] More particularly, at least one such turbomachine 6000 comprises a turbogenerator 100 which comprises at least one air filter 109, a first electrified turbocharger 151 for a low pressure stage comprising a low pressure compressor 101, a low pressure turbine 104, and a first electric machine 121 equipped with a first inverter, a second electrified turbocharger 152 for a high pressure stage comprising a high pressure compressor 102, a high pressure turbine 104, and a second electrified turbocharger 153 for a high pressure stage comprising a high pressure compressor 102, a high pressure turbine 104, and a second electrified turbocharger 154 for a high pressure stage comprising a high pressure compressor 104, a high pressure turbine 104, and a second electrified turbocharger 155 for a high pressure stage comprising a high pressure compressor 104, a high pressure turbine 104, and a second electrified turbocharger 156 for a high pressure stage comprising a high pressure compressor 104, a high pressure turbine 104, and a second electrified turbocharger 157 for a high pressure stage comprising a high pressure compressor 104, a high pressure turbine 104, and a second electrified turbocharger 158 for a high pressure stage comprising a high pressure compressor 104, a high pressure turbine 104, and a second electrified turbocharger 159 ... pressure 103, and a second electric machine 122 equipped with a second inverter, at least one heat recovery unit 106 by heat exchange between the air and the exhaust gases, at least one intercooler exchanger 105 (cooler), supplied with ambient air and arranged to cool the air between this low pressure compressor 101 and this high pressure compressor 102 through a heat transfer circuit with water or air or other fluid as refrigerant. The exhaust gases are guided to the outside by at least one exhaust pipe 120 (visible in [Fig.4] and [Fig.6] to [Fig. 10]).

[0044] More particularly still, at the outlet of the high-pressure compressor 102, such a heat recovery unit 106 is inserted before the gases enter a first combustion chamber 107 which is arranged to drive the high-pressure turbine 103, and a second combustion chamber 108 is inserted between the high-pressure turbine 103 and the low-pressure turbine 104, and is arranged to drive the low-pressure turbine 104.

[0045] [Fig.2] shows such an IRReGT 100 turbogenerator, in the particular case of a machine with separate low pressure (hereinafter LP) and high pressure (hereinafter HP) stages. In the low pressure stage a first shaft 111 connects a LP compressor 101 (which receives the air via an air filter 109) and a LP turbine 104. In the high pressure stage a second shaft 112 connects an HP compressor 102 and an HP turbine 103. An exchanger called an intercooler 105, supplied with ambient air, cools the air between the LP compressor 101 and the HP compressor 102. At the outlet of the HP compressor 102 a heat recovery unit 106 is inserted before the entry into a first combustion chamber 107 which drives the HP turbine 103. A second combustion chamber 108 is inserted between the HP turbine 103 and the LP turbine 104, to supply the latter, the gases exiting through the heat recovery unit 106.In this variant, the low-pressure stage and the high-pressure stage are separate, which is well suited to installation in a passenger vehicle, and allows for a reduction in the size of the pipes required for conveying the various fluids. And the modularity of this turbogenerator allows its components to be positioned in different locations depending on the space available.

[0046] [Fig.3] shows another IRReGT 100 turbogenerator, in the particular case of a coaxial machine, where coaxial shafts 110 each connect a compressor and a turbine, respectively low pressure (LP): LP compressor 101 and LP turbine 104, and high pressure (HP): HP compressor 102 and HP turbine 103. As in the case of [Fig.2], an intercooler exchanger 105, supplied with ambient air or another heat transfer fluid such as water or other, cools the air between the LP compressor 101 and the HP compressor 102. At the outlet of the HP compressor 102 a recuperator 106 is inserted before the entry into a first combustion chamber 107 which drives the HP turbine 103. The purpose of the recuperator 106 is to increase the air temperature at the inlet of the first combustion chamber by preheating the air. A second combustion chamber 108 is interposed between the HP turbine 103 and the LP turbine 104, to supply the latter. This variant with in-line architecture is well suited to a utility vehicle.

[0047] [Fig.6] to [Fig. 10] schematically illustrate a vehicle according to the invention, in a non-limiting variant, and the energy storage means of this vehicle and the turbomachine which equips it, remarkable for their small size and the good distribution of masses favorable to good road holding.

[0048] Advantageously, the turbogenerator 100 operates with a bio-fuel, or e-fuel, or similar type fuel. A traditional fuel can of course also be used.

[0049] More particularly, at least one intercooler exchanger 105 arranged to heat the passenger compartment of the electric motor vehicle 1000.

[0050] The passenger compartment can thus be heated by the intercooler exchanger 105 cooled with a heat transfer circuit using water, which is very efficient.

[0051] More particularly, this electric motor vehicle 1000 comprises electrical coupling means (also called “junction box”) for powering the at least one battery pack 2000 by the first inverter and by the second inverter. Specific connectors (mechanical for coupling, thermal for thermal energy, and electrical junction box type to supply electrical energy) provide the interface between the turbomachine 6000, in particular the turbogenerator 100 and the vehicle 1000.

[0052] In a variant, the electric motor vehicle 1000 comprises a chassis 8000 arranged to directly carry at least one battery pack 2000, at least one fuel tank 7000, at least one heat recovery unit 106 which comprises the at least one turbomachine 6000, and a rear crossmember 8500 carrying the rear axle of the electric motor vehicle 1000. More particularly, the at least one turbomachine 6000 is arranged on either side of the rear crossmember 8500.

[0053] In a variant, the electric motor vehicle 1000 comprises a chassis 8000 (visible in [Fig.5]) arranged to carry at least one battery pack 2000 or a lower structure 9000 carrying at least one turbomachine 6000 and at least one fuel tank 7000.

[0054] Advantageously, the accessories of the turbogenerator 100 (inverter, junction box, air filter 109, fuel tank 7000 and fuel pump, and others) are all under the floor 4000, and the trunk 5000 of the vehicle 1000 is not penalized.

[0055] If the use of a turbomachine 6000 comprising such a double-stage turbogenerator 100 is preferred due to its advantages, the invention is applicable with a turbomachine according to another thermodynamic architecture: GT (simple Gas Turbine), RGT (Recuperative Gas Turbine), IRGT (Intercooled Recuperative Gas Turbine), or as here IRReGT (Intercooled Recuperative Reheat Gas Turbine).

[0056] The innovation concerns the integration of the machine into a vehicle. This integration includes: mechanical integration, thermal integration, electrical integration. Integrating a turbogenerator allows for weight savings, but above all for increasing the autonomy of a low-cost electric vehicle.

[0057] In a non-limiting example of application, based on a vehicle designed to carry a 50 kWh battery pack, 20 kWh of battery are retained (approximately 100 km per day), which makes it possible to save the cost of the batteries corresponding to the 30 kWh removed. The cost of an integrated turbogenerator is lower than the cost of the battery, which allows a significant saving on the manufacturing cost price.

[0058] Releasing part of the batteries frees up volume for the installation of at least part of the turbogenerator, for example in place of the rear battery pack. Certain components can also be installed under the floor, and / or under the trunk of the vehicle. The integration then does not penalize the usable volume on the vehicle by the user. This modification also allows a significant reduction in the mass of the vehicle: taking the example above, instead of a mass of 250 kg represented by 30 kWh of battery, the total mass of a turbogenerator (approximately 110 kg) and a fuel tank (approximately 40 kg), allows a saving of approximately 100 kg.

[0059] The number of components is reduced, therefore few adaptation parts are necessary, they concern the fixing of each electrified turbocharger 151, 152, (which are preferably single-piece components), of each heat recovery unit 106 (single in the figures), of the intercooler exchanger 105, of the air filter 109, and of the inverters, as well as the second LP combustion chamber 108, the first HP combustion chamber 107 being preferably fixed directly to the heat recovery unit 106.

[0060] In a non-limiting variant, a lower structure 9000 carries at least one turbomachine 6000, and makes it possible to fix each turbogenerator 100 under the floor 4000, generally in place of a rear battery pack, and partly under the trunk 5000 at the rear of the vehicle 1000.

[0061] In yet another variant, particularly in the case of transformation of an already existing vehicle, the structure of the vehicle is modified by cutting out the trunk floor, which makes it possible to create a suitable structure allowing the turbogenerator to be integrated into it, via the underside of the body.

[0062] In yet another variant, a metal frame is made to carry the turbogenerator.

[0063] The electrical coupling system allows electricity to be returned to each battery.

[0064] Advantageously, the vehicle 1000 also includes a cooling circuit for the turbomachine 6000: taking air from the inside and injecting this air onto the hot parts of the machine, and may include an additional cooling circuit: taking air from under the body and blowing this air onto the hot parts.

[0065] In the case of a transformation of an existing vehicle to increase its autonomy, it is easy to remove part of the batteries located in the rear battery pack, and to integrate components such as fuel tank 7000, electric inverter, power electronics.

[0066] Such a transformation makes it possible to offer an energy extender based on a turbogenerator, at low cost, low mass, and which allows users to access long distances with their originally low-autonomy electric vehicles.

[0067] The invention makes it possible to propose, for electric or hybrid cars, a range extender for long-distance journeys. Equipped with a turbogenerator with a fuel tank, the system makes it possible to increase the range, to propose a long-range solution, to reduce the purchase cost for the user, to whom it is proposed to size the battery pack of his vehicle with a low capacity for daily journeys, thanks to the turbogenerator which is used as a range extender for long journeys.

[0068] The system allows the vehicle to be recharged with electricity from bio-fuel or e-fuel (fuels with low environmental impact).

[0069] The system also allows thermal energy to be produced to heat the vehicle (if there is a need for hot energy, such as during the winter season)

[0070] The device according to the invention makes it possible to reduce the mass of the vehicle by eliminating several kWh of battery, which an ordinary user generally does not need for more than 80% of the time the vehicle is used.

[0071] The volume occupied by the batteries and the electric machine of an electric vehicle is relatively high. The proposed solution reduces the volume of the batteries and allows not to penalize the volume of the passenger compartment or that of the trunk.

[0072] The proposed energy converter operates with a fuel with high energy density, and therefore provides additional autonomy.

[0073] In short, the invention makes it possible to reduce the overall cost of the vehicle (in particular by reducing the volume of the batteries), its mass, its electrical consumption, and its environmental impact (by lower consumption of specific materials for the batteries), as well as the energy consumption of the vehicle due to its lower mass.

[0074] The invention ensures the increase in the autonomy of the vehicle via a non-intrusive solution, and makes it possible to have a supply of thermal energy, for heating the passenger compartment, during the winter, which represents a significant energy requirement and which commonly limits the autonomy of electric vehicles in winter; therefore the invention allows the reduction of electrical energy consumption because the thermal energy is provided by the turbogenerator via thermal discharges and not by electrical consumption.

[0075] The invention eliminates user anxiety, which is common in cases of low autonomy, and makes it possible to overcome logistical problems linked to the unavailability of electrical charging terminals.

[0076] The traction motor remains solely electric, which ensures the simplicity of the drive train, and therefore that of maintenance.

[0077] The invention provides a low-cost solution for increasing the autonomy of a battery-powered electric vehicle, offering a long autonomy with a bio-fuel with low environmental impact. This solution makes it possible to retain all the advantages of electric vehicles: driving pleasure, very low maintenance, low noise level, ZEV “zero emission vehicle” mode in the city, while increasing autonomy, reducing energy demand and reducing cost.

Claims

Claims

1. Electric motor vehicle (1000) comprising at least one battery pack (2000) for powering an electric traction motor, said at least one battery pack (2000) being housed under a floor (4000) or under a trunk (5000) that said electric motor vehicle (1000) comprises, characterized in that said electric motor vehicle (1000) comprises a range extension device which comprises at least one IRReGT cycle turbomachine (6000) comprising a turbogenerator (100) with recovery and intermediate cooling and which is supplied by a fuel tank (7000) and which is arranged for recharging said at least one battery pack (2000) with energy.

2. Electric motor vehicle (1000) according to claim 1 characterized in that each said turbomachine (6000) which comprises said electric motor vehicle (1000) is housed under said floor (4000) or under said trunk (5000), or both under said floor (4000) and said trunk (5000).

3. Electric motor vehicle (1000) according to any one of claims 1 to 2 characterized in that said turbomachine (6000) comprises a said turbogenerator (100) which is a double-stage turbine with recovery and intermediate cooling.

4. Electric motor vehicle (1000) according to any one of claims 1 to 3 characterized in that said turbomachine (6000) comprises a said turbogenerator (100) which comprises at least one air filter (109), a first electrified turbocharger (151) for a low pressure stage comprising a low pressure compressor (101), a low pressure turbine (104), and a first electric machine (121) equipped with a first inverter, a second electrified turbocharger (152) for a high pressure stage comprising a high pressure compressor (102), a high pressure turbine (103), and a second electric machine (122) equipped with a second inverter, at least one heat recovery unit (106) by heat exchange between the air and the exhaust gases, at least one intercooler exchanger (105),supplied with ambient air or water from a heat transfer circuit and arranged to cool the air between said low pressure compressor (101) and said high pressure compressor (102).,

5. An electric motor vehicle (1000) according to claim 4 ca- characterized in that, at the outlet of said high pressure compressor (102), a said heat recuperator (106) is inserted before the entry of the gases into a first combustion chamber (107) which is arranged to drive said high pressure turbine (103), and in that a second combustion chamber (108) is inserted between said high pressure turbine (103) and said low pressure turbine (104), and is arranged to drive said low pressure turbine (104).

6. Electric motor vehicle (1000) according to any one of claims 4 to 5 characterized in that said intercooler exchanger (105) is arranged to heat the passenger compartment of said electric motor vehicle (1000).

7. Electric motor vehicle (1000) according to any one of claims 4 to 6 characterized in that said electric motor vehicle (1000) comprises electrical coupling means for powering said battery pack (2000) by said first inverter and by said second inverter.

8. Electric motor vehicle (1000) according to any one of claims 1 to 7 characterized in that said electric motor vehicle (1000) comprises a chassis (8000) arranged to directly carry said battery pack (2000), said fuel tank (7000), at least one heat recovery unit (106) included in said at least one turbomachine (6000), and a rear cross member (8500) carrying the rear axle of said electric motor vehicle (1000).

9. Electric motor vehicle (1000) according to claim 8 characterized in that said turbomachine (6000) is arranged on either side of said rear crossmember (8500).

10. Electric motor vehicle (1000) according to any one of claims 1 to 7 characterized in that said electric motor vehicle (1000) comprises a chassis (8000) arranged to carry said battery pack (2000) or a lower structure (9000) carrying said turbomachine (6000) and said fuel tank (7000).

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