WO2014103824A1 - Dispositif de récupération de la chaleur de l'échappement et procédé de récupération de la chaleur de l'échappement - Google Patents

Dispositif de récupération de la chaleur de l'échappement et procédé de récupération de la chaleur de l'échappement Download PDF

Info

Publication number
WO2014103824A1
WO2014103824A1 PCT/JP2013/083866 JP2013083866W WO2014103824A1 WO 2014103824 A1 WO2014103824 A1 WO 2014103824A1 JP 2013083866 W JP2013083866 W JP 2013083866W WO 2014103824 A1 WO2014103824 A1 WO 2014103824A1
Authority
WO
WIPO (PCT)
Prior art keywords
exhaust
heat recovery
recirculation
engine
exhaust heat
Prior art date
Application number
PCT/JP2013/083866
Other languages
English (en)
Japanese (ja)
Inventor
永井　宏幸
真一朗 溝口
Original Assignee
日産自動車株式会社
ルノー エス．ア．エス．
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日産自動車株式会社, ルノー エス．ア．エス． filed Critical 日産自動車株式会社
Publication of WO2014103824A1 publication Critical patent/WO2014103824A1/fr

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02G—HOT GAS OR COMBUSTION-PRODUCT POSITIVE-DISPLACEMENT ENGINE PLANTS; USE OF WASTE HEAT OF COMBUSTION ENGINES; NOT OTHERWISE PROVIDED FOR
    • F02G5/00—Profiting from waste heat of combustion engines, not otherwise provided for
    • F02G5/02—Profiting from waste heat of exhaust gases
    • F02G5/04—Profiting from waste heat of exhaust gases in combination with other waste heat from combustion engines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K15/00—Adaptations of plants for special use
    • F01K15/02—Adaptations of plants for special use for driving vehicles, e.g. locomotives
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
    • F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
    • F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
    • F01K23/065—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle the combustion taking place in an internal combustion piston engine, e.g. a diesel engine
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K9/00—Plants characterised by condensers arranged or modified to co-operate with the engines
    • F01K9/003—Plants characterised by condensers arranged or modified to co-operate with the engines condenser cooling circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
    • F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
    • F02D13/0261—Controlling the valve overlap
    • F02D13/0265—Negative valve overlap for temporarily storing residual gas in the cylinder
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/01—Internal exhaust gas recirculation, i.e. wherein the residual exhaust gases are trapped in the cylinder or pushed back from the intake or the exhaust manifold into the combustion chamber without the use of additional passages
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
    • F02M26/23—Layout, e.g. schematics
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
    • F02M26/23—Layout, e.g. schematics
    • F02M26/24—Layout, e.g. schematics with two or more coolers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
    • F02M26/23—Layout, e.g. schematics
    • F02M26/28—Layout, e.g. schematics with liquid-cooled heat exchangers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N5/00—Exhaust or silencing apparatus combined or associated with devices profiting by exhaust energy
    • F01N5/02—Exhaust or silencing apparatus combined or associated with devices profiting by exhaust energy the devices using heat
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02G—HOT GAS OR COMBUSTION-PRODUCT POSITIVE-DISPLACEMENT ENGINE PLANTS; USE OF WASTE HEAT OF COMBUSTION ENGINES; NOT OTHERWISE PROVIDED FOR
    • F02G2260/00—Recuperating heat from exhaust gases of combustion engines and heat from cooling circuits
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Definitions

  • This invention relates to an exhaust heat recovery device that recovers exhaust heat of an engine and regenerates it as kinetic energy.
  • An exhaust heat recovery device (Rankine cycle system) that recovers exhaust heat of the engine through cooling water or refrigerant and regenerates it as kinetic energy by rotating the expander by this heat has been put into practical use.
  • JP 2010-78216A proposes a method of recovering the heat of the exhaust gas passing through the pipe by providing a heat exchanger in the pipe of the exhaust gas recirculation apparatus (EGR).
  • EGR exhaust gas recirculation apparatus
  • EGR exhaust gas recirculation gas by EGR
  • the external EGR is provided with a valve in a pipe communicating from the exhaust pipe to the intake pipe, and the exhaust gas recirculation amount is adjusted by the valve.
  • the internal EGR adjusts the amount of recirculation of exhaust gas in the cylinder by overlapping the intake valve and the exhaust valve of the engine.
  • the internal EGR can return unburned hydrocarbons (HC) to the cylinders again before passing through the catalyst to reduce the HC emission amount, and the recirculation amount can be adjusted with good response only by controlling the intake and exhaust valves.
  • HC hydrocarbons
  • the external EGR has an advantage that the recirculation gas can be cooled, the recirculation amount can be increased, and knocking can be improved.
  • the present invention has been made in view of such problems, and in an exhaust heat recovery device that recovers heat of an exhaust gas recirculation device in an engine and regenerates it as an energy, an exhaust heat recovery device that can improve fuel efficiency is provided.
  • the purpose is to provide.
  • an exhaust heat recovery device that recovers exhaust heat of a vehicle engine and regenerates it as energy, and recirculates a part of the exhaust of the engine to the intake side;
  • a recirculation valve that controls the amount of exhaust gas that is recirculated, an exhaust heat recovery device that recovers exhaust heat from the exhaust recirculation passage, an expander that can be driven to rotate by the heat recovered by the exhaust heat recovery device, and an engine
  • a control device that controls the operation of the recirculation valve and the expander.
  • the control device controls the timing of the intake valve and the exhaust valve of the engine to recirculate the exhaust gas at the first recirculation amount, and controls the recirculation valve to control the exhaust gas to the second recirculation amount.
  • external EGR control for recirculation.
  • the ratio of the second recirculation amount is increased more than the first recirculation amount.
  • FIG. 1 is an explanatory diagram showing a configuration of a Rankine cycle system centering on an engine according to a first embodiment of the present invention.
  • FIG. 2A is an explanatory diagram illustrating an operation region of the Rankine cycle according to the first embodiment of this invention.
  • FIG. 2B is an explanatory diagram illustrating an operation region of the Rankine cycle according to the first embodiment of this invention.
  • FIG. 3 is an explanatory diagram showing the relationship between the ratio between the external EGR and the internal EGR and the vehicle speed when the Rankine cycle according to the first embodiment of the present invention is operated.
  • FIG. 4A is an explanatory diagram of heat exchange and its efficiency in the Rankine cycle of the first embodiment of the present invention.
  • FIG. 4A is an explanatory diagram of heat exchange and its efficiency in the Rankine cycle of the first embodiment of the present invention.
  • FIG. 4B is an explanatory diagram of heat exchange and its efficiency in the Rankine cycle of the first embodiment of the present invention.
  • FIG. 4C is an explanatory diagram of heat exchange and its efficiency in the Rankine cycle of the first embodiment of the present invention.
  • FIG. 5 is an explanatory diagram showing the relationship between the cooling water temperature and the fuel efficiency effect in the Rankine cycle of the first embodiment of the present invention.
  • FIG. 6 is a flowchart showing control of Rankine cycle operation executed by the controller according to the first embodiment of the present invention.
  • FIG. 7 is an explanatory diagram showing the configuration of a Rankine cycle system centering on the engine of the second embodiment of the present invention.
  • FIG. 8 is an explanatory diagram showing the configuration of a Rankine cycle system centering on the engine of the third embodiment of the present invention.
  • FIG. 1 is an explanatory diagram showing a configuration of a Rankine cycle system 1 centering on an engine 2 according to a first embodiment of the present invention.
  • FIG. 1 shows a cooling water circuit 10 of an engine 2 mounted on a vehicle and a Rankine cycle system 1 that recovers exhaust heat of the engine 2 to generate driving force.
  • the engine 2 includes an exhaust passage 3 and an intake passage 6.
  • the exhaust passage 3 includes an exhaust manifold 4, an exhaust passage 3 connected to a collecting portion of the exhaust manifold 4, a catalyst 5 provided in the exhaust passage 3, and a silencer 16.
  • the intake passage 6 includes an intake manifold 7, a collector portion 8 connected to the intake manifold 7, and an upstream air filter 9.
  • the EGR 20 includes an EGR passage 21, an EGR valve 22, and a heat exchanger 23.
  • the cooling water circuit 10 of the engine 2 is provided with a cooling water pump 11, a radiator 12, and a thermostat 13.
  • the cooling water circuit 10 circulates the cooling water to the engine 2 or the like by the cooling water pump 11, and cools the cooling water by exchanging heat between the cooling water and the atmosphere by the radiator 12.
  • the thermostat 13 opens and closes the passage to the radiator 12 according to the cooling water temperature, and prevents the cooling water temperature from being lowered.
  • Part of the cooling water that has passed through the engine 2 flows to the heat exchanger 23 of the EGR 20.
  • the heat exchanger 23 performs heat exchange between the exhaust gas passing through the EGR passage 21 and the cooling water, and raises the cooling water temperature.
  • the cooling water that has passed through the heat exchanger 23 is circulated again by the cooling water pump 11 via a heater 41 and an evaporator 42 described later.
  • a part of the cooling water that has passed through the engine 2 is circulated again by the cooling water pump 11 via the evaporator 42.
  • the Rankine cycle circuit 40 includes a heater 41, an evaporator 42, an expander 43, a condenser 44, and a refrigerant pump 46.
  • the refrigerant pump 46 is connected to the crank pulley 45 of the engine 2 via a belt 47, is driven to rotate as the crank pulley 45 rotates, and circulates the refrigerant to the Rankine cycle circuit 40.
  • the refrigerant pump 46 is coaxially connected to the expander 43 and rotates together with the expander 43.
  • the refrigerant discharged from the refrigerant pump 46 exchanges heat with the cooling water circulating in the engine 2 in the evaporator 42, and further exchanges heat with the cooling water heated in the heat exchanger 23 in the heater 41. From phase to gas phase.
  • the gas-phase refrigerant that has been subjected to heat exchange and has become high temperature and high pressure is expanded in the expander 43, and energy is given to the expander 43 by the volume change.
  • the expander 43 converts energy into rotational energy, rotationally drives the coaxial refrigerant pump 46, and rotationally drives the crank pulley 45 via the belt 47. This assists driving of the engine. That is, the energy generated by the recovered heat can be used as the regenerative power of the engine 2.
  • the gas-phase refrigerant that has exited the expander 43 is cooled and converted from the gas phase to the liquid phase by exchanging heat with the atmosphere in the condenser 44, and is circulated through the Rankine cycle circuit 40 again by the refrigerant pump 46.
  • the condenser 44 is provided with a fan 48 to promote cooling of the refrigerant.
  • the controller 30 controls a transmission gear ratio (not shown) and a driving force of the engine 2 based on signals such as an accelerator pedal opening (APO), a brake pedal depression amount (BRK), a vehicle speed (VSP), and the like. And drive the vehicle.
  • APO accelerator pedal opening
  • BRK brake pedal depression amount
  • VSP vehicle speed
  • controller 30 controls whether to rotate the expander 43 of the Rankine cycle system 1 based on these signals, thereby regenerating exhaust heat energy and assisting the driving force of the engine 2. Control.
  • the controller 30 also controls the amount of exhaust gas recirculated to the intake side of the engine 2 by controlling the opening degree of the EGR valve 22.
  • the controller 30 controls the variable valve timing mechanism 31 to control the opening / closing timing of the intake valve 2a and the exhaust valve 2b of the engine 2.
  • the Rankine cycle system 1 is configured as described above, and recovers exhaust heat of the engine 2 and generates regenerative power by the recovered heat to assist the engine driving force and improve the fuel efficiency of the engine. it can.
  • the controller 30 determines whether to assist the power of the engine 2 by operating the Rankine cycle system 1 based on the coolant temperature, the outside air temperature, the engine rotational speed Ne, the vehicle speed VSP, and the like. In the embodiment of the present invention, recovering exhaust heat and operating the Rankine cycle system 1 to assist the power of the engine 2 will be referred to as “operating the Rankine cycle” hereinafter.
  • FIG. 2A and FIG. 2B are explanatory diagrams showing an operation region of the Rankine cycle according to the first embodiment of the present invention.
  • FIG. 2A shows the Rankine cycle operating region where the horizontal axis is the outside air temperature and the vertical axis is the engine water temperature (cooling water temperature).
  • FIG. 2B shows the Rankine cycle operating region when the horizontal axis is the engine rotation speed and the vertical axis is the engine torque (engine load).
  • the Rankine cycle is operated when the operating region satisfies both of these conditions, that is, the driving force of the engine 2 is driven by rotating the expander 43 with the refrigerant that has recovered the heat. Assist.
  • Rankine cycle Stop operation As shown in FIG. 2A, in the low water temperature side region where the cooling water temperature is low (for example, 80 ° C.) and priority is given to warming up the engine 2, and in the high outside temperature side region where the load of the air conditioner or the like increases, Rankine cycle Stop operation. This is because in such a region, operating the Rankine cycle increases the load, which in turn reduces the fuel efficiency of the engine 2.
  • the Rankine cycle operation is stopped in the region where the engine rotational speed is low and the capacity of the exhaust heat is small and the region on the high rotational speed side where the friction of the expander 43 increases. Since the expander 43 is connected to the crankshaft of the engine 2, the rotation speed of the expander 43 depends on the engine rotation speed. It is difficult for the expander 43 to have a highly efficient structure with little friction even when the rotational speed is high. Therefore, the expander 43 is designed so that the friction is small and the efficiency is high in the engine rotation speed region where the Rankine cycle is frequently operated. The Rankine cycle is efficiently operated in such a rotational speed range.
  • the exhaust gas is recirculated to the intake side. Circulation takes place.
  • the external EGR is provided with an EGR valve 22 in an EGR passage 21 communicating from the exhaust passage 3 to the intake passage 6, and the exhaust gas recirculation amount is adjusted by the opening degree of the EGR valve 22.
  • the internal EGR overlaps the timing at which the intake valve 2a of the engine 2 is opened and the timing at which the exhaust valve 2b is closed, thereby adjusting the exhaust gas recirculation amount.
  • unburned hydrocarbons can be returned to the cylinders again before passing through the catalyst to reduce HC emissions, and the amount of recirculation can be adjusted only by controlling the valve opening.
  • the amount can be controlled with good response.
  • it is necessary to finely control the recirculation amount, and it is preferable to actively use the internal EGR.
  • the external EGR can cool the recirculated exhaust gas by the heat exchanger 23 and does not raise the intake air temperature, so that the fuel efficiency can be improved. Further, there is an advantage that the amount of exhaust gas recirculation can be increased. In particular, when traveling in a constant speed range at a high vehicle speed, such as on an expressway, the response is not emphasized. Therefore, the fuel efficiency is improved by increasing the recirculation amount by the external EGR.
  • the internal EGR and the external EGR have respective merits. Which method is used to recirculate the exhaust gas or to combine these to recirculate the exhaust gas depends on the fuel efficiency of the engine 2. A big influence.
  • the controller 30 appropriately change the exhaust gas recirculation amount and the ratio of the recirculation amount between the external EGR and the internal EGR in accordance with the running state of the vehicle and the operating state of the engine. As described above, the fuel efficiency of the engine 2 can be improved by the operation of the Rankine cycle and the control of the external EGR and the internal EGR.
  • FIG. 3 is an explanatory diagram showing the relationship between the overlap amount (O / L) between the intake valve 2a and the exhaust valve 2b when operating the Rankine cycle of the first embodiment of the present invention.
  • the upper part of FIG. 3 shows the relationship between the EGR rate and the overlap amount (O / L) between the intake valve 2a and the exhaust valve 2b.
  • the lower part shows the relationship between the heat release amount (heat amount radiated from the exhaust to the medium) in the heat exchanger 23 and the overlap amount (O / L) between the intake valve 2a and the exhaust valve 2b.
  • the upper limit amount of exhaust gas recirculated during operation of the engine 2 is determined.
  • the ratio between the external EGR and the internal EGR is determined based on the vehicle speed with respect to the upper limit amount. That is, the higher the vehicle speed is, the smaller the overlap amount (O / L) between the intake valve 2a and the exhaust valve 2b is controlled to increase the external EGR ratio.
  • the heat radiation efficiency in the condenser 44 is increased by the traveling wind. This is because the thermal efficiency of the Rankine cycle is increased, and the amount of heat radiated from the exhaust gas to the medium in the heat exchanger 23 is increased.
  • the upper limit amount of the exhaust gas recirculated in the cylinder is kept constant, and the overlap amount (O / L) between the intake valve 2a and the exhaust valve 2b is increased as the vehicle speed is increased to increase the ratio of the external EGR. As a result, it is possible to recover heat by operating the Rankine cycle and improve fuel efficiency of the engine 2 by lowering the exhaust temperature.
  • the ratio of the internal EGR is increased. This is because, as described above, the internal EGR can adjust the recirculation amount only by controlling the valve opening, and therefore has an advantage that the recirculation amount can be controlled with good response. Thus, the exhaust gas recirculation amount can be appropriately controlled even in the transient operation of the engine 2.
  • 4A to 4C are explanatory diagrams of the relationship between the vehicle speed and the heat exchange in the Rankine cycle of the first embodiment of the present invention.
  • FIG. 4A shows the relationship between the heat capacity received by the medium in the heat exchanger 23 and the fuel efficiency when the Rankine cycle is operated, with respect to the vehicle speed. As shown in FIG. 4A, it is shown that as the vehicle speed increases, the ratio between the heat receiving capacity in the heat exchanger 23 and the fuel efficiency effect due to Rankine cycle operation increases, and the fuel efficiency effect improves.
  • 4B and 4C show the relationship between the vehicle speed and the ratio of the external EGR to the internal EGR, and the relationship between the heat dissipation capability (capacity of cooling the medium) in the condenser 44. If the vehicle speed is high, the traveling wind becomes large, and the heat dissipation capability in the condenser 44 is also improved. Accordingly, the cooling effect of the exhaust gas in the EGR 20 is also improved by the operation of the Rankine cycle. Therefore, as described above with reference to FIG. 3, the fuel efficiency can be improved by increasing the ratio of the external EGR to the internal EGR as the vehicle speed increases.
  • FIG. 5 is an explanatory diagram showing the relationship between the cooling water temperature and the fuel consumption effect in the Rankine cycle of the first embodiment of the present invention.
  • the fuel efficiency of the engine 2 is slightly improved by cooling the exhaust gas in the heat exchanger 23 of the EGR 20.
  • the Rankine cycle When the coolant temperature reaches the Rankine cycle operating range (80 to 100 ° C.), the Rankine cycle is operated and the driving force of the engine 2 is assisted by the rotation of the expander 43, so the fuel efficiency is greatly improved. To do. If the cooling water temperature exceeds the Rankine cycle operating range, the fuel efficiency will decrease. Further, when the coolant temperature becomes higher (from 110 ° C.), the exhaust of the EGR 20 cannot be sufficiently cooled, and the fuel efficiency is lowered.
  • the Rankine cycle operating range 80 to 100 ° C.
  • FIG. 6 is a flowchart showing the Rankine cycle operation control executed by the controller 30 according to the first embodiment of the present invention.
  • the controller 30 always acquires the vehicle speed VSP and the coolant temperature (step S10).
  • the controller 30 determines whether or not the operation region of the Rankine cycle system is based on the water temperature and the cooling water temperature with reference to the maps shown in FIGS. 2A and 2B (step S20).
  • the operation region of the Rankine cycle system is determined by the cooling efficiency with which the medium is cooled by the condenser 44. That is, the fuel efficiency increases when the Rankine cycle system is operated due to the difference between the heat recovered by the medium in the heat exchanger 23 and the heat generated when the medium is cooled by the condenser 44 (assuming the driving force of the engine 2). If possible, this is the operating area of the Rankine cycle system. Since the cooling efficiency of the condenser 44 increases even when the vehicle speed is high, the operation region of the Rankine cycle system is set. Even when the cooling water temperature is high, the amount of heat received by the medium increases, so the temperature difference increases, and the operation region of the Rankine cycle system is set.
  • step S30 the controller 30 increases the exhaust gas recirculation amount (second recirculation amount) by the external EGR, and the exhaust gas by the internal EGR.
  • the recirculation amount (first recirculation amount) is decreased. Thereby, the ratio of the external EGR to the internal EGR is increased.
  • the controller 30 increases the amount of exhaust gas that passes through the EGR passage 21 by controlling the opening degree of the EGR valve 22 in the external EGR.
  • the controller 30 controls the variable valve timing mechanism 31 to reduce the overlap period between the opening timing of the intake valve 2a and the closing timing of the exhaust valve 2b, and the recirculation amount of the exhaust gas in the cylinder. Decrease. More specifically, the controller 30 decreases the exhaust gas recirculation amount by bringing the timing at which the intake valve 2a is opened and the timing at which the exhaust valve 2b are closed closer to top dead center. The ratio of the exhaust gas recirculated can be changed by such control.
  • the ratio of the exhaust gas recirculation amount by the external EGR is made larger than the exhaust gas recirculation amount by the internal EGR within a range not exceeding the upper limit value of the exhaust gas recirculated in the cylinder.
  • step S40 the controller 30 decreases the exhaust gas recirculation amount (second recirculation amount) by the external EGR, and recirculates the exhaust gas by the internal EGR.
  • the circulation amount (first recirculation amount) is increased. Thereby, the ratio of the external EGR to the internal EGR is lowered.
  • the controller 30 controls the opening degree of the EGR valve 22 to reduce the amount of exhaust gas passing through the EGR passage 21.
  • the controller 30 controls the variable valve timing mechanism 31 in the internal EGR to expand the overlap period between the timing of opening the intake valve 2a and the timing of closing the exhaust valve 2b, thereby re-exhaust gas in the cylinder. Increase circulation. More specifically, the controller 30 increases the exhaust gas recirculation amount by advancing the timing of opening the intake valve 2a and delaying the timing of closing the exhaust valve 2b. The ratio of the exhaust gas recirculated can be changed by such control.
  • step S10 After the process of step S30 or step S40, the process after step S10 is repeated.
  • the heat recovered by the cooling water in the heat exchanger 23 is transmitted to the medium by the evaporator 42 and the heater 41.
  • the expander 43 is rotationally driven by the heat of the medium to assist the driving force of the engine 2.
  • the controller 30 sets the ratio of the second recirculation amount by the external EGR to the first recirculation amount by the internal EGR. Control to increase.
  • the exhaust gas recirculated to the intake side by the external EGR can be increased to recover the heat of the exhaust gas and to reduce the temperature of the recirculated exhaust gas.
  • the fuel efficiency can be improved by collecting the exhaust heat of the engine 2 and the fuel efficiency can be improved by lowering the temperature of the recirculated exhaust gas.
  • step S30 when the ratio of the exhaust gas recirculation amount by the external EGR is made larger than the internal EGR, the total exhaust gas recirculation amount (the internal EGR and the external EGR) than the upper limit value of the exhaust gas recirculated in the cylinder. And the total).
  • the combustion stability can be improved, and the fuel consumption can be improved while suppressing the vibration of the vehicle.
  • FIG. 7 is an explanatory diagram showing the configuration of the Rankine cycle system 1 centering on the engine 2 according to the second embodiment of the present invention.
  • the embodiment of the second embodiment is a modification of the first embodiment, in which Rankine cycle refrigerant is directly introduced into the heat exchanger 23 of the EGR 20 and heat exchange is performed between the exhaust of the EGR 20 and the refrigerant.
  • Other configurations and the operation of the controller 30 are the same as those in the first embodiment.
  • the amount of heat received by the refrigerant in the Rankine cycle increases, so that the temperature difference in the Rankine cycle can be increased.
  • the Rankine cycle can be operated with higher efficiency, and the fuel efficiency of the engine can be improved. Since the exhaust gas of the EGR 20 reaches several hundred degrees, it is necessary to select an appropriate refrigerant that is not affected by heat.
  • FIG. 8 is an explanatory diagram showing the configuration of the Rankine cycle system 1 centering on the engine 2 according to the third embodiment of the present invention.
  • the third embodiment is a modification of the first embodiment.
  • a cooling circuit 50 and a heat exchanger 51 are provided separately, and the Rankine cycle refrigerant is cooled by the cooling circuit 50. Configured to do.
  • Other configurations and the operation of the controller 30 are the same as those in the first embodiment.
  • the cooling circuit 50 includes a pump 52 for circulating the refrigerant, a heat exchanger 51 for exchanging heat with the Rankine cycle refrigerant, and a sub-radiator 53 for cooling the refrigerant by exchanging heat with the atmosphere.
  • the cooling circuit 50 is configured to be able to cool electronic devices (motor MOT, inverter INV, intercooler CAC, etc.) mounted on the vehicle.
  • the cooling circuit 50 is further provided, and the Rankine cycle is cooled by the refrigerant that has less fluctuation than the series cooling in the air in the heat exchanger 51, so that the difference between the high temperature and the low temperature particularly in the Rankine cycle when the vehicle speed fluctuates. Can be bigger. As a result, the Rankine cycle can be operated with higher efficiency, and the fuel efficiency of the engine can be improved.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)
  • Exhaust-Gas Circulating Devices (AREA)
  • Engine Equipment That Uses Special Cycles (AREA)

Abstract

La présente invention concerne un dispositif de récupération de chaleur d'échappement équipé d'un système d'expansion capable de tourner et d'être entraîné grâce à la chaleur récupérée par un appareil de récupération de chaleur d'échappement servant à récupérer la chaleur d'échappement dans un canal de recirculation d'échappement permettant de faire recirculer, du côté d'admission d'air, une partie de l'échappement provenant d'un moteur. Le dispositif de récupération de chaleur d'échappement exécute : une commande d'EGR interne pour commander la synchronisation d'une soupape d'admission d'air et d'une soupape de refoulement d'échappement d'un moteur et une première quantité de recirculation d'échappement ; et une commande d'EGR externe pour commander une soupape de recirculation et faire recirculer une seconde quantité de recirculation de gaz d'échappement. Lorsque le système d'expansion est tourné et entraîné grâce à la chaleur récupérée par l'appareil de récupération de chaleur d'échappement, la proportion de la seconde quantité de recirculation est davantage augmentée que celle de la première quantité de recirculation.
PCT/JP2013/083866 2012-12-27 2013-12-18 Dispositif de récupération de la chaleur de l'échappement et procédé de récupération de la chaleur de l'échappement WO2014103824A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2012-285849 2012-12-27
JP2012285849A JP2015232274A (ja) 2012-12-27 2012-12-27 排熱回収装置

Publications (1)

Publication Number Publication Date
WO2014103824A1 true WO2014103824A1 (fr) 2014-07-03

Family

ID=51020911

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2013/083866 WO2014103824A1 (fr) 2012-12-27 2013-12-18 Dispositif de récupération de la chaleur de l'échappement et procédé de récupération de la chaleur de l'échappement

Country Status (2)

Country Link
JP (1) JP2015232274A (fr)
WO (1) WO2014103824A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3057299A1 (fr) * 2016-10-11 2018-04-13 Peugeot Citroen Automobiles Sa Ensemble de motorisation a boucle de rankine

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010242582A (ja) * 2009-04-03 2010-10-28 Denso Corp エンジンの廃熱制御装置
JP2012087687A (ja) * 2010-10-20 2012-05-10 Mitsubishi Heavy Ind Ltd ディーゼルエンジンのトルク変動抑制制御装置及び方法
JP2012102619A (ja) * 2010-11-08 2012-05-31 Hino Motors Ltd 廃熱回収システム

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010242582A (ja) * 2009-04-03 2010-10-28 Denso Corp エンジンの廃熱制御装置
JP2012087687A (ja) * 2010-10-20 2012-05-10 Mitsubishi Heavy Ind Ltd ディーゼルエンジンのトルク変動抑制制御装置及び方法
JP2012102619A (ja) * 2010-11-08 2012-05-31 Hino Motors Ltd 廃熱回収システム

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3057299A1 (fr) * 2016-10-11 2018-04-13 Peugeot Citroen Automobiles Sa Ensemble de motorisation a boucle de rankine
WO2018069587A1 (fr) * 2016-10-11 2018-04-19 Psa Automobiles Sa Ensemble de motorisation a boucle de rankine

Also Published As

Publication number Publication date
JP2015232274A (ja) 2015-12-24

Similar Documents

Publication Publication Date Title
US10100690B2 (en) Method and system for exhaust emissions control
JP5481737B2 (ja) 内燃機関の廃熱利用装置
JP4492672B2 (ja) ハイブリッドシステムの制御装置
JP5293235B2 (ja) エンジンの吸気制御方法及びその装置
US20160003127A1 (en) Intake-air cooling device for engine and method for cooling engine
WO2013031287A1 (fr) Dispositif d'utilisation de chaleur perdue
US20160230643A1 (en) Engine cooling system
KR20130081664A (ko) 과급 연소 기관에 의해 작동되는 차량용 냉각 장치
JP2013181394A (ja) エンジンの廃熱回収装置
KR102648821B1 (ko) 하이브리드 차량용 열에너지 제어 장치 및 그의 열에너지 제어 방법과 그를 포함하는 하이브리드 차량
CN109830783B (zh) 一种基于大学生电动方程式赛车的整车热管理系统及其控制方法
JP2002161748A (ja) 車両用電動ウオーターポンプ装置
RU2518764C1 (ru) Устройство и способ для нагрева теплоносителя, циркулирующего в системе охлаждения
JP2019137279A (ja) ハイブリッド車両
JP2019156108A (ja) 車両の温度制御装置
CN201074559Y (zh) 车用内燃机余热回收利用机构
WO2014132755A1 (fr) Dispositif de refroidissement et procédé de refroidissement pour dispositif de recirculation d'échappement
WO2014103824A1 (fr) Dispositif de récupération de la chaleur de l'échappement et procédé de récupération de la chaleur de l'échappement
CN101059108A (zh) 车用内燃机余热回收利用机构及方法
CN202672204U (zh) 混合动力推土机冷却系统
JP2012144205A (ja) ハイブリッド車両及び内燃機関の制御装置
JP2014234801A (ja) エンジンの廃熱利用装置
JP2016014339A (ja) 廃熱回生システム
JP3329123B2 (ja) ディーゼルエンジンの吸気温度制御装置
CN107605580B (zh) 一种车用余热回收与空调制冷复合循环系统及其控制方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 13867365

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 13867365

Country of ref document: EP

Kind code of ref document: A1