ELECTRIC MOTOR VEHICLE FEATURING A RANGE EXTENSION DEVICE COMPRISING A TURBOGENERATOR

Abstract

The invention relates to an electric motor vehicle, comprising a battery pack and a range extender comprising a two-stage IRReGT cycle turbogenerator (100) with recovery and intercooling, comprising a first compressor (101) and a first turbine (104) linked by a low-pressure shaft (111), a second compressor (102) and a second turbine (103) linked by a high-pressure shaft (112), an intercooler (105) arranged to cool the air between the first compressor (101) and the second compressor (102), and a heat recovery loop, arranged to recover energy, at the level of said intercooler (105) and / or the bearings (P) of said low-pressure shaft (111) and high-pressure shaft (112), and / or at the level of a heat recovery unit (106), in particular a heat recovery loop operates according to an organic Rankine cycle (ORC) or steam Rankine cycle (SRC). Figure from the summary: [Fig.10]

Description

Title of the invention: ELECTRIC MOTOR VEHICLE COMPRISING AN EXTENSION DEVICE AUTONOMY COMPRISING A TURBOGENERATOR

[0001] The invention relates to an electric motor vehicle comprising at least one battery pack for powering an electric traction motor, and comprising a range extension device which comprises at least one IRReGT cycle turbogenerator with recovery and intermediate cooling and intermediate heating and which is powered by a fuel tank and which is arranged for recharging said at least one battery pack with energy and / or for powering at least one electric traction motor.

[0002] The search for autonomy for hybrid electric or electric vehicles is a constant concern for manufacturers, and it is difficult to achieve a compromise between autonomy, vehicle mass, safety of use, manufacturing cost, and acquisition and operating cost for the user.

[0003] Gas turbine-type energy converters are an interesting solution as a range extender in series hybrid vehicles. Such a 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.

[0004] It is possible to envisage several variants of thermodynamic cycles suitable for this application.

[0005] We know simple recuperative cycles (RGT = Recuperative Gas Turbine), and also IRReGT cycles (Intercooled Recuperative Gas Turbine), that is to say with a turbogenerator with recovery and intermediate cooling and intermediate reheating.

[0006] The gas turbine cycle with intercooler, recuperator and heater (Intercooled Re-generative Reheat Gas Turbine IRReGT) is a cycle with high potential for automotive applications. This cycle makes it possible to achieve very high efficiency but also very high power density (high specific net work), higher than that obtained with a simple GT gas turbine (Simple Gas Turbine), or with a cycle with RGT recuperator (Recuperative Gas Turbine), or even a cycle with intercooler and IRGT recuperator (Intercooled Recuperative Gas Turbine), with significantly higher efficiency and specific net work, particularly at different operating temperatures, for example 950°C, 1100°C, 1250°C.

[0007] The RGT cycle requires a combustion chamber while the IRReGT cycle requires two combustion chambers, one on a low-pressure circuit, and the other on a high-pressure circuit. The IRReGT cycle also requires the installation of an intercooler exchanger, supplied with ambient air or water from a heat transfer circuit and arranged to cool the air between a first low-pressure compressor and a second high-pressure compressor.

[0008] The objective of the present invention is to optimize the energy efficiency of such a turbogenerator, and to overcome the problem of thermal discharges linked to an IRReGT cycle, by proposing to recover, wherever possible, thermal energy to transform it into reusable electrical energy.

[0009] To achieve this objective, the invention proposes an electric motor vehicle comprising at least one battery pack for powering an electric traction motor, and comprising a range extension device which comprises at least one IRReGT cycle turbogenerator with recuperation and intermediate cooling and intermediate heating and which is powered by a fuel tank and which is arranged for recharging said at least one battery pack with energy and / or for powering at least one electric traction motor. According to the invention, said at least one turbogenerator is a double-stage turbomachine with recuperation and intermediate cooling, comprising a first low-pressure compressor linked to a first low-pressure turbine by a low-pressure shaft, and a second high-pressure compressor linked to a second high-pressure turbine by a high-pressure shaft, and at least one intercooler exchanger,supplied with ambient air or water from a heat transfer circuit and arranged to cool the air between said first low pressure compressor and said second high pressure compressor, and said at least one turbogenerator comprises at least one thermal recovery loop, which is arranged to recover energy, at said intercooler exchanger and / or at the guide bearings of said low pressure shaft and said high pressure shaft, and / or at a heat recovery unit that said at least one turbogenerator comprises at the outlet of said second high pressure compressor and before the gases enter a first combustion chamber arranged to drive said second high pressure turbine, said first low pressure turbine being driven by a second combustion chamber interposed between said second high pressure turbine and said first low pressure turbine.

[0010] Thanks to the invention, the main energy losses are converted into energy sources that can be used on board the vehicle.

[0011] Advantageously, at least one said thermal recovery loop operates according to an organic Rankine cycle ORC (Organic Rankine Cycle in English) or according to a steam Rankine cycle SRC (Steam Rankine Cycle in English).

[0012] It is thus possible to improve the overall efficiency of the turbogenerator.

[0013] Advantageously, said at least one turbogenerator comprises at least one air filter, a first electrified turbocharger for a low pressure stage comprising said first low pressure compressor and said first low pressure turbine on said low pressure shaft, and a first electrical machine equipped with a first inverter, a second electrified turbocharger for a high pressure stage comprising said second high pressure compressor and said second high pressure turbine on said high pressure shaft and a second electrical machine equipped with a second inverter, at least one said heat recovery unit by heat exchange between the air and the exhaust gases, at least one said intercooler exchanger, supplied with ambient air or water from a heat transfer circuit and arranged to cool the air between said first low pressure compressor and said second high pressure compressor.

[0014] This means that proven components that are easy to source are used.

[0015] Advantageously, at least one said thermal recovery loop is a first thermal recovery loop for heat exchange with an intercooler exchanger that comprises said at least one turbogenerator, and forms a closed-loop circulation circuit of a first heat transfer fluid, and comprises a first heat exchanger with the ambient air, a first circulation pump arranged to control the circulation of said first heat transfer fluid, and an auxiliary heat exchanger with the ambient air coupled to said intercooler exchanger.

[0016] Again, such a recovery loop uses trading components, which do not require any particular development.

[0017] Advantageously, in said first loop, at the outlet of said auxiliary heat exchanger with the ambient air, said first heat transfer fluid passes through a second electrical machine that comprises said at least one turbogenerator in a high pressure stage, then a second inverter associated with said second electrical machine, before joining a first electrical machine that comprises said at least one turbogenerator in a low pressure stage, then a first inverter associated with said first electrical machine, before successively exchanging heat with each of the bearings of a first low pressure shaft then of a second high pressure shaft, that comprises said at least one turbogenerator, before returning to said first heat exchanger with the ambient air.

[0018] The direction of circulation takes into account the ability of the bearings to tolerate higher temperatures than the other components.

[0019] Advantageously, at least one said thermal recovery loop is a second loop which comprises a second heat exchanger with the ambient air and a second first circulation pump arranged to control the successive crossing, by a second heat transfer fluid, of a second electrical machine. that comprises said at least one turbogenerator in a high pressure stage, then a second inverter associated with said second electrical machine, before joining a first electrical machine that comprises said at least one turbogenerator in a low pressure stage, then a first inverter associated with said first electrical machine, before successively exchanging heat with each of the bearings of a first low pressure shaft then of a second high pressure shaft, that comprises said at least one turbogenerator, before returning to said second heat exchanger with the ambient air.

[0020] This increases the heat exchange capacities, at the cost of a very simple circuit.

[0021] Advantageously, at least one said thermal recovery loop is an ORC loop which operates in a closed loop according to an organic Rankine cycle, and in which an organic heat transfer fluid circulates, and which comprises a condenser, a pump, a first evaporator coupled with said first heat exchanger with the ambient air, a second evaporator coupled with said second heat exchanger with the ambient air, and an expander arranged to expand the fluid from high pressure to low pressure by driving a generator for producing electrical energy.

[0022] Coupling the ORC loop improves the electrical efficiency of the turbogenerator and reduces fuel consumption.

[0023] More particularly, said ORC loop comprises a third evaporator, crossed by the heat transfer fluid after said second evaporator then said first evaporator, which third evaporator is coupled with a third heat exchanger with the ambient air, on the gas circuit at the outlet of said heat recovery unit, the circuit of said ORC loop joining said expander after crossing said third evaporator.

[0024] A portion of the energy contained in the exhaust gases is thus recovered.

[0025] Advantageously, at least one said thermal recovery loop is an SRC loop which operates in a closed loop according to a steam Rankine cycle, and in which a fluid in the vapor state circulates, said SRC loop comprising, in the direction of the flow of the heat transfer fluid, a vapor condenser, an SRC pump, a vapor evaporator linked to an exchanger on the exhaust gas outlet circuit downstream of said heat recovery unit, and a steam expander associated with a steam generator.

[0026] The steam Rankine cycle is suitable for heat exchanges with high temperature fluids.

[0027] Advantageously, to recover energy from the condenser, said steam condenser of said SRC loop is coupled with said evaporator of said ORC loop.

[0028] The passage of the heat transfer fluid from the ORC loop into the steam condenser is thus used to recover further energy.

[0029] 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] schematically illustrates the architecture of a double turbogenerator IRReGT thermodynamic cycle stage, similar to [Fig.2], the low pressure stage and the high pressure stage being separated, with a heat exchanger associated with a recuperator at the combustion chamber outlet, and where the different large arrows symbolize thermal losses, at the level of the bearings of the turbine and compressor shafts, at the level of the inverters also called inverters, at the level of the electrical machines, at the level of the intercooler exchanger, and at the level of the exhaust; - [Fig.5] schematically illustrates a first variant of the invention, comprising the addition of a first thermal recovery loop to the turbogenerator. This first loop comprises a separate circuit, with a first heat exchanger with the ambient air, a first circulation pump, and an auxiliary heat exchanger with the ambient air coupled to the intercooler exchanger, the circuit passes through the electrical machines, the inverters, and the bearings of the turbine and compressor shafts; - [Fig.6] schematically illustrates another variant, where a first loop only concerns the exchange with the intercooler exchanger, the circuit a second loop comprising a second heat exchanger with the ambient air and a second first circulation pump, this second loop the circuit crosses the electrical machines, the inverters, and the bearings of the turbine and compressor shafts; - [Fig.7] schematically illustrates another variant, built on the basis of the circuit shown in [Fig.6], and which comprises an ORC loop operating in a closed loop according to an organic Rankine cycle, and which comprises a condenser, a pump, a first evaporator coupled to the first heat exchanger with the ambient air, and a second evaporator coupled to the second heat exchanger with ambient air, and an expander associated with a generator; - [Fig.8] schematically illustrates an alternative variant to that of [Fig.7] schematically illustrates another variant, constructed on the basis of the circuit represented in [Fig.6], and which comprises an ORC loop operating in a closed loop according to an organic Rankine cycle, but whose connection between the evaporators and the expander is carried out by a particular circuit comprising a third evaporator linked to an exchanger on the gas circuit at the outlet of the heat recovery unit; - [Fig.9] schematically illustrates another variant, built on the basis of the circuit shown in [Fig.6], and which comprises, in addition to the ORC loop, an SRC loop according to a steam Rankine cycle, comprising a steam condenser, an SRC pump, a steam evaporator linked to the exchanger on the exhaust gas outlet circuit downstream of the heat recovery unit, and a steam expander associated with a generator; - [Fig. 10] illustrates another variant based on the circuits shown in [Fig.8] and [Fig.9], in which the energy is recovered from the condenser.

[0030] [Fig.l] schematically illustrates an electric motor vehicle 1000 with battery, 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. Non-limitingly, this battery pack 2000 is housed under a floor or under a trunk that this electric motor vehicle 1000 comprises.

[0031] This electric motor vehicle 1000 comprises a range extension device which comprises at least one gas turbine type energy converter, which is IRReGT cycle, and comprises at least one turbogenerator 100 with recovery and intermediate cooling. This at least one turbogenerator 100 is in particular powered by a fuel tank 7000, and is arranged for recharging this at least one battery pack 2000 with energy, and / or for powering at least one electric traction motor of the vehicle 1000. In particular the turbogenerator 100, illustrated in [Fig.2], is a micro-turbomachine operating with a liquid fuel or a gas, with a double stage with recovery and intermediate cooling.

[0032] According to the invention, at least one turbogenerator 100 is a two-stage turbogenerator, which comprises means arranged to substantially reduce the heat discharges at the level of the intercooler exchanger, the exhaust, the electrical machines, the bearings, and the inverters linked to the electrical machines that it comprises. To this end, the device comprises the addition of at least one thermal recovery loop to the turbogenerator 100.

[0033] In an advantageous implementation, this two-stage turbogenerator is coupled to at least one thermal recovery system operating according to a Rankine cycle.

[0034] As seen in [Fig.2] and in [Fig.3], more particularly, such a turbogenerator 100 comprises at least one air filter 109, a first electrified turbocharger 151 for a low pressure stage comprising a first low pressure compressor 101, a first low pressure turbine 104, a low pressure shaft 111, and a first electric machine 121 equipped with a first inverter 1210, a second electrified turbocharger 152 for a high pressure stage comprising a second high pressure compressor 102, a second high pressure turbine 103, a high pressure shaft 112, and a second electric machine 122 equipped with a second inverter 1220, at least one heat recovery unit 106 by heat exchange between the air and the exhaust gases, at least one exchanger 105, called an intercooler (cooler), supplied with ambient air or another fluid heat transfer fluid such as water or other, coming from a heat transfer circuit,and arranged to cool the air between this first low-pressure compressor 101 and this second 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.

[0035] More particularly still, at the outlet of the second 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 second high-pressure turbine 103, and a second combustion chamber 108 is inserted between the second high-pressure turbine 103 and the first low-pressure turbine 104, and is arranged to drive the first low-pressure turbine 104.

[0036] [Fig.2] shows such an IRReGT 100 turbogenerator, in the particular case of a machine comprising a separate low pressure stage (hereinafter LP) and high pressure stage (hereinafter HP), which is well suited to installation in a passenger vehicle, and makes it possible to reduce 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.

[0037] [Fig.3] shows another IRReGT 100 turbogenerator, in the particular case of a coaxial machine, where coaxial shafts 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, this variant with in-line architecture is well suited to a utility vehicle.

[0038] The proposed turbogenerator 100 technology is very advantageous for replacing the internal combustion engine in highly electric traction chains triified, particularly for PHEV (Plug-in Hybrid Electric Vehicles) vehicles with series hybrid architecture (Series Hybrid Electric Vehicles). This technology promises the following advantages: low emissions, low noise, no vibrations, reduced maintenance (reduced to changing the oil filter), and the ability to operate with several types of fuels.

[0039] The invention proposes to couple the turbogenerator system 100 with a Rankine-type thermal recovery loop. This coupling makes it possible to improve the overall electrical efficiency of the turbogenerator system, to take advantage of the thermal discharges in the different branches to transform part of the thermal into work, and to create an innovative thermal architecture, making it possible to take advantage of these thermal discharges to meet the energy needs of the vehicle.

[0040] The invention can in particular be applied to a thermodynamic cycle turbogenerator type energy converter comprising a double stage, of the intercooled recuperative reheat gas turbine (IRReGT) type.

[0041] The present description essentially concerns the thermodynamic architecture part of the turbogenerator, with its integration at the level of the thermal architecture of the vehicle.

[0042] Thermal discharges at the level of the different components of the turbogenerator system are present at different power levels and at different temperatures. [Fig.4] illustrates the different losses by thermal discharges, symbolized by large arrows: - heat discharges at the intercooler exchanger 105: the objective is to cool the compressed air which is at a temperature between 100°C and 180°C (depending on the compression ratio). The intercooler exchanger 105 can be cooled by air, or by water, or by another type of heat transfer fluid. For better efficiency, the air leaving the intercooler exchanger 105 must be cooled to temperatures below 55°C; - thermal discharges at the P bearings of BP 101, HP 102 compressors, and BP 104 and HP 103 turbines: several bearing technologies exist. There are oil bearings (known in automotive turbochargers) where the oil temperature is between 100°C and 125°C. We also know of "foil bearings" or aerodynamic bearings which do not require an oil flow but rather an air flow. We also know of compressed air bearings, and magnetic bearings. But, in all cases the need for cooling for the bearings is unavoidable; - thermal discharges at the level of cooling of the electric machines 121 and 122 (Electric Motor Generator), in fact the electric machine operates in motor mode when starting the turbogenerator 100 to drive the com presser and the turbine at high speed, then switch to generator mode when the power supplied by the turbine exceeds the power of the compressor. Each electrical machine consists of a rotor (magnetized) which turns in a fixed stator. The casing and the space between the rotor and the stator must be cooled to limit the material temperature and especially the temperature of the rotor to avoid demagnetizing it. The temperature must be kept below 70°C; - thermal discharges at the cooling level of the inverters 1210 and 1220: the current supplied by the electrical machines 121 and 122 is a three-phase current. The role of the inverters 1210 and 1220 is to transform this three-phase alternating current into direct current to charge the battery pack 2000. These electrical and / or electronic components release heat and must be cooled to temperatures below 65°C; - thermal discharges at the exhaust: these are the exhaust gases leaving the heat recuperator 106 associated with the heat exchanger at the outlet of the combustion chamber, which are at temperatures of the order of 250°C and more, depending on the efficiency of the recuperator 106. The more efficient the recuperator 106, the lower the temperature of the gases at the outlet. Conventionally, dissipation is carried out in an auxiliary circuit comprising a heat transfer fluid, a circulation pump, and a radiator coupled to a fan or similar.

[0043] Thus, the turbogenerator cycle presents thermal losses through the various components (intercooler, exhaust, electrical machines, bearings, inverters). These thermal losses are currently rejected into the ambient air via heat exchangers. These thermal losses present an unrecovered work potential and therefore a potential for increasing the efficiency of the system.

[0044] An effective way to achieve this increase in system efficiency is to add a Rankine cycle type heat recovery system, particularly steam.

[0045] Rankine cycles exist and are known elsewhere, but the integration of a Rankine cycle with a double-stage turbogenerator in a motor vehicle is a novelty. The other novelty lies in the overall thermal architecture of the system which allows thermal energy to be recovered at different levels.

[0046] The Rankine cycle uses a fluid that evaporates by passing through a two-phase state (liquid - gas). This fluid can be water, or ethanol, or even organic fluids (R134a, R1234yf, R245fa, R1233zd, or others). Each type of fluid has particular physical properties (evaporation temperature at a given pressure, flammability, GWP (Global Warming Potential) or global warming potential (GWP) which is the heating power of a gas relative to the heating power of the same mass of carbon dioxide, and other parameters).

[0047] A Rankine cycle that uses an organic fluid as the working fluid is called an ORC or Organic Rankine Cycle. A Rankine cycle that uses water as the working fluid is called an SRC or Steam Rankine Cycle. Either one is usable here.

[0048] A particularity of the invention therefore consists in coupling an organic Rankine cycle ORC or a steam Rankine cycle SRC with a turbogenerator cycle of the IRReGT (Intercooled Recuperative Reheat TurboGenerator) type, i.e. a gas turbine cycle with intercooler, recuperator and heater, and where the organic Rankine cycle ORC, or respectively the steam Rankine cycle SRC, recovers energy at the level of the different components of the system. Depending on the temperature levels, the components are arranged to recover the maximum amount of thermal energy.

[0049] Like any type of thermodynamic machine, the IRReGT cycle has thermal discharges at the level of different components as explained above. The objective of this invention is to take advantage of these thermal discharges to operate a thermodynamic cycle allowing the maximum amount of thermal energy to be recovered. This is notably possible thanks to the implementation of a thermal architecture and an organic Rankine type thermal recovery system allowing the transformation of the lost thermal energy into useful mechanical work and consequently into electrical power through an electrical machine.

[0050] This makes it possible to recover the lost thermal energy and transform it into mechanical energy and therefore makes it possible to increase the overall efficiency of the machine which is the equivalent of the quotient of the sum of the mechanical (or electrical) powers produced, by the quantity of fuel injected.

[0051] [Fig.5] illustrates a first variant, comprising the addition of a first loop of heat recovery 130 to the turbogenerator 100. This first loop 130 comprises a separate circuit, with a first heat exchanger with the ambient air 133, a first circulation pump 134, and an auxiliary heat exchanger with the ambient air 135 coupled to the intercooler exchanger 105; at the outlet of this auxiliary heat exchanger with the ambient air 135 the heat transfer fluid passes through the second electric machine 122, then its inverter 1220, before joining the first electric machine 121 then its inverter 1210, before successively exchanging heat with each of the bearings of the first shaft 111 then of the second shaft 112, before returning to the first heat exchanger with the ambient air 133. The heat transfer fluid circulating in this first loop 130 can be glycolated water, or any other suitable fluid. The arrangement can be different, we can also enter first into the first electrical machine 121, or enter into the inverters before passing through the electrical machines. It is advantageous to enter the bearings at the end of the loop, because they accept higher temperatures. As energy is recovered, the fluid temperature increases.

[0052] [Fig.6] illustrates another variant, where a first loop 130 only concerns the exchange with the intercooler exchanger 105, and comprises the first heat exchanger with the ambient air 133, the first circulation pump 134, and the auxiliary heat exchanger with the ambient air 135 coupled to the intercooler exchanger 105. And a second loop 170 comprises a second heat exchanger with the ambient air 136 and a second first circulation pump 137, which controls, as for [Fig.5], the successive crossing of the second electrical machine 122, its inverter 1220, the first electrical machine 121, its inverter 1210, the bearings of the first shaft 111 then of the second shaft 112, before the return to the second heat exchanger with the ambient air 136.The heat transfer fluid in this second loop 170 may be different from the heat transfer fluid of the first loop 130, for example oil instead of glycolated water), to recover energy at the intercooler level. The fact of separating the two circuits is linked to the fact that the temperature levels are not the same.

[0053] [Fig.7] illustrates another variant, constructed on the basis of the circuit shown in [Fig.6], and where advantage is taken of a Rankine cycle. Advantageously, an ORC loop 140 is used which operates in a closed loop according to the principle of Rankine cycles, and which comprises six main elements: a condenser 141, a pump 142 (and an electric pump motor), at least one evaporator, here a first evaporator 143 coupled to the first heat exchanger with the ambient air 133, and a second evaporator 144 coupled to the second heat exchanger with the ambient air 136, an expander 145 associated with a generator 146, and a volume of organic heat transfer fluid which circulates between these elements. This expander 145 is a machine which makes it possible to expand the high pressure fluid / gas to low pressure by driving an alternator in order to generate electrical energy. The expander 145 may comprise a screw, piston, or scroll expander, or other.More particularly, the circuit also passes through a utilization circuit 147, for example a passenger compartment heater. The assembly is connected by pipes and is regulated by a controller, sensors and actuators (valves). The ORC loop 140 produces electricity which is routed to the battery pack 2000, or a traction motor, or other utilization points within the vehicle 1000. The ORC loop 140 can be supplied in the form of a compact module, assembled or pre-assembled in the factory, easy to implement and above all very easy to operate, because, working at low temperatures and pressures, in a closed circuit, such an ORC module has an excellent service life and good availability.

[0054] In another variant, illustrated in [Fig.8] on the basis of the circuit represented in [Fig.7], it is proposed to recover the thermal energy at the output of the heat recovery unit 106 of the turbogenerator system 100. Indeed, the turbogenerator 100 rejects energy at a relatively high temperature (in particular greater than 250°C). It is therefore possible to take advantage of this to recover part of this energy and increase the overall efficiency of the system. For this purpose, the ORC loop 140 incorporates a third evaporator 149, crossed by the heat transfer fluid after the second evaporator 144 then the first evaporator 143, this third evaporator 149 is coupled with a third heat exchanger with the ambient air 148, on the gas circuit at the outlet of the heat recovery unit 106. The circuit of the ORC loop 140 thus modified joins the expander 145 after passing through the third evaporator 149.

[0055] Yet another variant is illustrated in [Fig.9], based on the circuit shown in [Fig.7], consists of adding an SRC loop 160 operating according to an SRC cycle (Steam Rankine Cycle) which makes it possible to recover the energy at the recuperator outlet. Indeed, as mentioned above, the temperature of the gases is relatively high, and recovering the energy is feasible and more efficient with a Rankine cycle operating with water, or ethanol, or a mixture of water + ethanol. This closed SRC loop 160 comprises, in the direction of the flow of the heat transfer fluid, a steam condenser 161, an SRC pump 162, a steam evaporator 163 linked to an exchanger 164 on the exhaust gas outlet circuit downstream of the heat recovery unit 106, and a steam expander 165 associated with a generator 166. The steam condenser 161 (Steam Condenser) will reject the energy but at a relatively high temperature (of the order of 100°C, water condensation temperature at 1 bar).So it contains energy too.

[0056] [Fig. 10] illustrates another variant based on the circuits shown in [Fig.8] and [Fig.9], in which the energy is recovered from the condenser. The steam condenser 161 of the SRC loop 160 is then coupled with the evaporator 149 of the ORC loop 140. Thus, advantageously, the ORC fluid passes back into the steam condenser 161, to recover more energy.

[0057] Using such recovery systems on an IRReGT turbogenerator cycle makes it possible to boost efficiency and achieve very low fuel consumption levels.

[0058] In short, compared to an IRReGT cycle where the thermal energy must be evacuated outside the system, an architecture is proposed here which makes it possible to recover part of this energy and transform it into useful mechanical energy (and consequently electrical energy).

[0059] This architecture takes into account the different temperature levels of thermal discharges in the system.

[0060] This architecture is not limited to the advantageous variants illustrated by the figures; the arrangement of the components may be different, depending on the temperature levels of the thermal discharges.

[0061] By recovering the thermal energy usually evacuated via exchangers to the ambient air, and by transforming part of this energy into useful energy (mechanical or electrical), it is possible to boost the overall efficiency of the turbogenerator, and considerably improve the power produced, while achieving very low fuel consumption levels.

[0062] This makes it possible to reduce the quantity of fuel injected for the same target output power, and therefore to reduce fuel consumption.

[0063] It is still possible to reduce the battery pack, and therefore the mass of the vehicle, and consequently its energy consumption.

[0064] The technical advantages are as follows: increased efficiency and reduced consumption, improved thermal / energy management, simplification / reduction of the number of exchangers on the front of the vehicle.

[0065] The invention also makes it possible to integrate the turbogenerator in place of all or part of the battery pack, without impacting the architecture of the vehicle.

[0066] The invention has an economic technical interest. Indeed, it makes it possible to propose a low-cost converter which can be easily integrated into an electric or hybrid vehicle, to hybridize its battery and propose a motor vehicle with high autonomy, low cost and low environmental impact offering a long autonomy with a bio-fuel with low environmental impact.

[0067] This solution allows the advantages of electric vehicles to be retained: driving pleasure, very low maintenance, low noise level, while increasing autonomy and reducing operating costs.

[0068] The turbogenerator coupled with the ORC cycle makes it possible to boost efficiency and reduce consumption. This is of particular interest for utility vehicle type applications, where the turbogenerator will operate for longer over the lifetime of the vehicle.

Claims

Claims

1. Electric motor vehicle (1000) comprising at least one battery pack (2000) for powering an electric traction motor, and comprising a range extension device which comprises at least one IRReGT cycle turbogenerator (100) with recuperation and intermediate cooling and intermediate heating and which is supplied by a fuel tank (7000) and which is arranged for recharging said at least one battery pack (2000) with energy and / or for powering at least one electric traction motor, characterized in that said at least one turbogenerator (100) is a double-stage turbomachine with recuperation and intermediate cooling, comprising a first low-pressure compressor (101) connected to a first low-pressure turbine (104) by a low-pressure shaft (111), and a second high-pressure compressor (102) connected to a second high-pressure turbine (103) by a high-pressure shaft (112),and 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 first low pressure compressor (101) and said second high pressure compressor (102), and characterized in that said at least one turbogenerator (100) comprises at least one thermal recovery loop, which is arranged to recover energy, at said intercooler exchanger (105) and / or at the guide bearings (P) of said low pressure shaft (111) and said high pressure shaft (112), or / and at a heat recovery unit (106) that said at least one turbogenerator (100) comprises at the outlet of said second high pressure compressor (102) and before the gases enter a first combustion chamber (107) arranged to drive said second high pressure turbine (103),said first low pressure turbine (104) being driven by a second combustion chamber (108) interposed between said second high pressure turbine (103) and said first low pressure turbine (104).,

2. Electric motor vehicle (1000) according to claim 1 characterized in that at least one said thermal recovery loop operates according to an organic Rankine cycle ORC or according to a vapor Rankine cycle SRC.

3. Electric motor vehicle (1000) according to claim 1 or 2 characterized in that said at least one turbogenerator (100) comprises at least at least one air filter (109), a first electrified turbocharger (151) for a low pressure stage comprising said first low pressure compressor (101) and said first low pressure turbine (104) on said low pressure shaft (111), and a first electric machine (121) equipped with a first inverter (1210), a second electrified turbocharger (152) for a high pressure stage comprising said second high pressure compressor (102) and said second high pressure turbine (103) on said high pressure shaft (112), and a second electric machine (122) equipped with a second inverter (1220), at least one said heat recovery unit (106) by heat exchange between the air and the exhaust gases, at least one said intercooler exchanger (105), supplied with ambient air or water from a heat transfer circuit and arranged to cool the air between said first low pressure compressor (101) and said second high pressure compressor pressure (102).

4. Electric motor vehicle (1000) according to any one of claims 1 to 3 characterized in that at least one said thermal recovery loop is a first thermal recovery loop (130) for heat exchange with an intercooler exchanger (105) that comprises said at least one turbogenerator (100), and forms a closed-loop circulation circuit of a first heat transfer fluid, and comprises a first heat exchanger with the ambient air (133), a first circulation pump (134) arranged to control the circulation of said first heat transfer fluid, and an auxiliary heat exchanger with the ambient air (135) coupled to said intercooler exchanger (105).

5. Electric motor vehicle (1000) according to claim 4 characterized in that, in said first loop (130), at the outlet of said auxiliary heat exchanger with the ambient air (135) said first heat transfer fluid passes through a second electrical machine (122) which comprises said at least one turbogenerator (100) in a high pressure stage, then a second inverter (1220) associated with said second electrical machine (122), before joining a first electrical machine (121) which comprises said at least one turbogenerator (100) in a low pressure stage, then a first inverter (1210) associated with said first electrical machine (121), before successively exchanging heat with each of the bearings (P) of a first low pressure shaft (111) then of a second high pressure shaft (112), that

6.

7.

8. comprises said at least one turbogenerator (100), before returning to said first heat exchanger with the ambient air (133). Electric motor vehicle (1000) according to any one of claims 1 to 5 characterized in that at least one said thermal recovery loop is a second loop (170) which comprises a second heat exchanger with the ambient air (136) and a second first circulation pump (137) arranged to control the successive crossing, by a second heat transfer fluid, of a second electrical machine (122) which comprises said at least one turbogenerator (100) in a high pressure stage, then a second inverter (1220) associated with said second electrical machine (122), before joining a first electrical machine (121) which comprises said at least one turbogenerator (100) in a low pressure stage, then a first inverter (1210) associated with said first electrical machine (121), before successively exchanging heat with each of the bearings (P) of a first low pressure shaft (111) then of a second shaft (112) high pressure,which comprises said at least one turbogenerator (100), before returning to said second heat exchanger with the ambient air (136)., Electric motor vehicle (1000) according to claims 4 to 6 characterized in that at least one said thermal recovery loop is an ORC loop (140) which operates in a closed loop according to an organic Rankine cycle, and in which an organic heat transfer fluid circulates, and which comprises a condenser (141), a pump (142), a first evaporator (143) coupled with said first heat exchanger with ambient air (133), a second evaporator (144) coupled with said second heat exchanger with ambient air (136), and an expander (145) arranged to expand the high pressure fluid to low pressure by driving a generator (146) for producing electrical energy. Electric motor vehicle (1000) according to claim 7 characterized in that, to recover the thermal energy at the outlet of said heat recovery unit (106), said ORC loop (140) comprises a third evaporator (149), crossed by the heat transfer fluid after said second evaporator (144) then said first evaporator (143), which third evaporator (149) is coupled with a third heat exchanger with the ambient air (148), on the gas circuit at the outlet of said heat recovery unit (106), the circuit of said ORC loop (140) re- joining said expander (145) after passing through said third evaporator (149).

9. Electric motor vehicle (1000) according to claims 4 to 6 characterized in that at least one said thermal recovery loop is an SRC loop (160) which operates in a closed loop according to a steam Rankine cycle, and in which a fluid in the vapor state circulates, said SRC loop (160) comprising, in the direction of the flow of the heat transfer fluid, a vapor condenser (161), an SRC pump (162), a vapor evaporator (163) linked to an exchanger (164) on the exhaust gas outlet circuit downstream of said heat recovery unit (106), and a vapor expander (165) associated with a steam generator (166).

10. Electric motor vehicle (1000) according to claim 9 characterized in that, to recover the energy on the condenser, said steam condenser (161) of said SRC loop (160) is coupled with said evaporator (149) of said ORC loop (140).

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