JP5397314B2 - Vehicle thermal management system - Google Patents

Description

  The present invention relates to a vehicle thermal management system, and more particularly to an improvement of a system related to an improvement in heat distribution efficiency.

  In recent years, for the purpose of further improving environmental performance and the like, improvement in utilization efficiency of heat generated in vehicles has been demanded. Conventionally, a vehicle thermal management system including an exhaust heat recovery device as found in Patent Document 1 has been proposed.

  The vehicle thermal management system described in Patent Document 1 includes an exhaust heat recovery unit that recovers the heat of the exhaust gas flowing from the exhaust pipe of the engine using boiling latent heat. Then, a fluid such as water is transferred to each part of the vehicle as a heat transfer medium, so that the recovered heat is used for warming up the engine or the like, heating the vehicle interior, and the like.

JP 2008-230422 A

  By the way, depending on the heat transfer destination, the temperature and the heat exchange performance are different, and the circulation amount of the heat transfer medium capable of maintaining high heat transfer performance is different for each heat transfer destination. Therefore, in the heat management system capable of switching the heat transfer destination, the amount of circulation of the heat transfer medium may be excessive and insufficient due to the combination of the heat transfer destinations that supply heat, and the heat transport performance may deteriorate.

  The present invention has been made in view of such circumstances, and a problem to be solved is to provide a vehicle thermal management system capable of transferring heat with high efficiency regardless of the heat transfer destination. There is.

  The invention according to claim 1 of the present invention supplies heat to a plurality of heat transfer destinations installed in the vehicle through circulation of the heat transfer medium, and selects a heat transfer destination for transferring heat from the plurality of heat transfer destinations. The premise is a vehicle thermal management system that can be switched automatically. And in order to solve the said subject, invention of Claim 1 adjusts the circulation amount of a heat conveyance medium by storing a heat conveyance medium in the heat conveyance destination which stops conveyance of heat.

  In the above configuration, the circulation amount of the heat transfer medium in the entire system is adjusted by storing the heat transfer medium in the heat transfer destination where the heat transfer is stopped. Therefore, the circulation amount of the heat transfer medium in the entire system can be optimized in accordance with the temperature and heat exchange performance of the heat transfer destination that is supplying heat. Therefore, according to the above configuration, heat can be transferred with high efficiency regardless of the heat transfer destination.

  In addition, in order to accurately control the circulation amount of the heat transfer medium in the entire system, it is necessary to grasp the storage amount of the heat transfer medium at the resting heat transfer destination. The storage amount of the heat transfer medium in each heat transfer destination is estimated from the pressure of the heat transfer medium in the heat transfer destination, for example, as in claim 2, or in the heat transfer destination, as in claim 3. It can be estimated from the temperature of the heat transfer medium.

  In the heat management system of the present invention, the recovery unit that recovers the heat supplied to the heat transfer destination is configured as a boiling device that applies heat to the heat transfer medium and vaporizes the heat transfer medium. The present invention can be applied to a system as described in claim 4 configured as a condenser for removing heat from the heat transfer medium and liquefying the heat transfer medium. As the heat transfer medium in this case, water can be used as in claim 5. Further, as the recovery device in this case, as in the sixth aspect, a recovery device that recovers heat from the exhaust of the engine can be used.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic which shows typically the whole structure of the thermal management system of the vehicle which concerns on one Embodiment of this invention. 6 is a schematic diagram schematically showing a configuration of a control system of the thermal management system of the embodiment. (A)-(c) Schematic which shows the storage operation | movement of the heat transfer medium in the thermal management system of the embodiment. The flowchart of the storage control routine of the heat transfer medium employ | adopted as the embodiment. The time chart which shows an example of the control aspect of the embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a vehicle thermal management system according to the present invention will be described in detail with reference to FIGS. This heat management system is configured to use water as a heat transfer medium and supply heat to a heat transfer destination of each part of the vehicle by supplying vaporized water (steam).

  FIG. 1 shows an overall configuration of a vehicle thermal management system according to the present embodiment. As shown in the figure, this thermal management system includes an exhaust heat recovery unit 3 that recovers heat of exhaust flowing through the exhaust pipe 2 of the engine 1. The exhaust heat recovery device 3 is a boiling device that performs heat exchange between the exhaust gas and the heat transfer medium, and boiles the heat transfer medium introduced as a liquid through the heat exchange and discharges it as steam. Connected to the exhaust heat recovery device 3 are a steam pipe 4 for sending out the vapor of the heat transfer medium and a liquid pipe 5 for introducing the liquid heat transfer medium.

  On the other hand, this heat management system includes a heater 6, an engine warmer 7, a mission warmer 9, a heat accumulator 10, and a Rankine cycle system 11 as heat transfer destinations recovered by the exhaust heat recovery device 3.

  The heater 6 is a heat exchanger that heats the air blown into the passenger compartment by heat exchange between the steam and the heat transfer medium. The vehicle to which this management system is applied is provided with another heater 12 that warms the air blown into the passenger compartment by the heat of engine cooling water.

  The engine warmer 7 is a heat exchanger that warms up the engine 1 through heat exchange between the steam of the heat transfer medium and the wall surface of the engine 1. The mission warmer 9 is a heat exchanger that warms up the transmission 8 through heat exchange between the steam of the heat transfer medium and the wall surface of the transmission 8.

  On the other hand, the heat accumulator 10 includes a heat insulating container and a heat storage medium accommodated therein, and the supplied heat is stored therein. The Rankine cycle system 11 is a system for extracting power from the vapor of the heat transfer medium, an expander 13 that generates power by adiabatic reversible expansion of the heat transfer medium vapor, and condensing the vapor of the heat transfer medium to form a liquid. And a pump 15 that performs adiabatic reversible compression of the heat transfer medium that has become liquid.

  Each of these heat transfer destinations also functions as a condenser that takes heat from the heat transfer medium and liquefies the heat transfer medium. Each heat transfer destination (6, 7, 9, 10, 11) is closed with an IN valve 6i, 7i, 9i, 10i, 11i that closes the connection between the steam pipe 4 and the heat transfer destination by closing the valve. OUT valves 6 o, 7 o, 9 o, 10 o, and 11 o are provided to cut off the connection between the liquid pipe 5 and the heat transfer destination by valves.

FIG. 2 shows the configuration of the control system of such a vehicle thermal management system. As shown in the figure, the control system of the thermal management system is configured around an electronic control unit 16.
The electronic control unit 16 includes a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and an input / output port (I / O). Here, the CPU performs various arithmetic processes related to the control of the thermal management system, and the ROM stores a control program and data. The RAM temporarily stores the calculation results of the CPU, the detection results of the sensors, and the like, and the I / O functions as an interface that mediates exchange of signals with the outside.

  The output port of the electronic control unit 16 has IN valves 6i, 7i, 9i, 10i, 11i and OUT valves 6o, 7o, 9o, 10o, 11o of the respective heat transfer destinations (6, 7, 9, 10, 11). Are connected to each other, and their opening / closing is controlled by the electronic control unit 16. In addition, pressure sensors 6 s, 7 s, 9 s, 10 s, and 11 s provided at each heat transfer destination are connected to the input port of the electronic control unit 16, and the detection results thereof are input to the electronic control unit 16. . These pressure sensors 6s, 7s, 9s, 10s, and 11s are sensors that detect the pressure of the heat transfer medium in the heat transfer destination.

  In the vehicle thermal management system of the present embodiment configured as described above, heat is supplied to a plurality of heat transfer destinations installed in the vehicle through circulation of the heat transfer medium, and a plurality of heat transfer destinations are also provided. The heat transfer destination for transferring heat from the inside is selectively switched according to the situation. Then, by storing the heat transfer medium at the heat transfer destination where the heat transfer is stopped, the circulation amount of the heat transfer medium in the entire system is adjusted.

Such storage of the heat transfer medium in the present embodiment is performed in the following manner.
As shown in FIGS. 3A to 3C, the condenser 20 that is a heat transfer destination is connected to the steam pipe 4 via the steam pipe 21 and the IN valve 22, and the liquid pipe 23, OUT The liquid pipe 5 is connected via a valve 24. In the state of FIG. 3A, both the IN valve 22 and the OUT valve 24 are opened, and the steam of the heat transfer medium is introduced into the condenser 20 from the steam pipe 4. That is, at this time, heat is supplied to the condenser 20.

  Here, as shown in FIG. 3B, when only the IN valve 22 is closed, the inflow of steam to the condenser 20 is shut off, and the heat supply is stopped. If this state is left for a while, the temperature of the steam remaining in the steam line 21 and the condenser 20 decreases and condenses. As a result, the pressure in the condenser 20 decreases, and as shown in FIG. 3C, the liquid heat transfer medium flows from the liquid pipe 5 to the liquid pipe 23 through the open OUT valve 24. become. Therefore, if the OUT valve 24 is closed when an appropriate amount of the heat transfer medium flows, a necessary amount of the heat transfer medium can be stored in the condenser 20.

  FIG. 4 shows a flowchart of a heat transfer medium storage control routine applied to the present embodiment. The processing of this routine is executed individually for each of the heat transfer destinations (6, 7, 9, 10, 11), and is executed by the electronic control unit 16 at predetermined control cycles.

  When this routine is started, the electronic control unit 16 first determines in step S100 whether or not the heat transfer destination is excluded from the heat transfer target, that is, the heat supply to the heat transfer destination is stopped. It is determined whether or not. If the heat transfer destination is the target of heat transfer (S100: NO), the electronic control unit 16 opens both the IN valve and the OUT valve in step S101, and then performs the process of this routine. Exit.

  On the other hand, if the heat transfer destination is not subject to heat transfer (S100: YES), the electronic control unit 16 in step S102, the amount of the heat transfer medium that stores the target medium storage amount Qd in the heat transfer destination. Is calculated as the target value. In step S103, the electronic control unit 16 closes the IN valve and opens the OUT valve.

  Thus, when only the OUT valve is opened, the heat transfer medium existing as a gas in the condenser is condensed, and the pressure Pl in the condenser is lowered. As a result, the heat transfer medium (liquid) in the liquid pipe 5 is sucked into the condenser side through the opened OUT valve.

  In step S104, the electronic control unit 16 calculates the amount of the heat transfer medium stored in the condenser (medium storage amount Qm) from the pressure Pl in the condenser. In step S105, the electronic control unit 16 calculates this amount. Compare with storage amount Qd. If the medium storage amount Qm has not reached the target medium storage amount Qd (S105: NO), the electronic control unit 16 returns to step S103 and stands by while maintaining the current state. On the other hand, if the medium storage amount Qm is equal to the target medium storage amount Qd (S105: YES), the electronic control unit 16 closes both the IN valve and the OUT valve in step S106, and ends the processing of this routine. .

  FIG. 5 shows an example of the control mode of this embodiment. In the example shown in the figure, the heat recovered by the exhaust heat recovery device 3 is first sent to the mission warmer 9 to warm up the transmission 8, and then the heat is sent to the engine warmer 7 to warm up the engine 1. Like to do.

  When the warm-up of the transmission 8 is started at time t0, the IN valve 9i and the OUT valve 9o of the mission warmer 9 are opened. At this time, the other heat transfer destinations are in a state in which only the OUT valve is opened, whereby the storage of the heat transfer medium to the heat transfer destination is started. At time t1, when the storage of the necessary amount of the heat transfer medium is completed and the circulation amount of the heat transfer medium in the entire system is adjusted, the OUT valve of the heat transfer destination other than the mission warmer 9 is closed.

  At subsequent time t2, warming up of the transmission 8 is completed, and warming up of the engine 1 is started instead. Therefore, the IN valve 7i and the OUT valve 7o of the engine warmer 7 are opened at this time t2. On the other hand, the heat transfer destination other than the engine warmer 7 is in a state in which only the OUT valve is opened, whereby the storage of the heat transfer medium to the heat transfer destination is started. At time t3, when the storage of the necessary amount of heat transfer medium is completed and the circulation amount of the heat transfer medium in the entire system is adjusted, the OUT valve of the heat transfer destination other than the engine warmer 7 is closed. Thereafter, this state is continued until the warm-up of the engine 1 is completed.

According to the vehicle thermal management system of the present embodiment described above, the following effects can be obtained.
(1) In the present embodiment, the heat transfer medium is stored in a heat transfer destination where heat transfer is suspended, thereby adjusting the circulation amount of the heat transfer medium in the entire system. Therefore, the circulation amount of the heat transfer medium in the entire system can be optimized in accordance with the temperature and heat exchange performance of the heat transfer destination that is supplying heat. Therefore, according to the present embodiment, heat can be transferred with high efficiency regardless of the heat transfer destination.

  (2) In this embodiment, since the heat transfer medium for adjusting the circulation amount is stored at the heat transfer destination, it is not necessary to provide a special container for storage. Therefore, adjustment of the circulation amount of the heat transfer medium according to the situation can be performed with a simple configuration.

In addition, the said embodiment can also be changed and implemented as follows.
In the above embodiment, the heat management system including the heater 6, the engine warmer 7, the mission warmer 9, the heat accumulator 10, and the Rankine cycle system 11 as heat transfer destinations has been described. However, the present invention is different in the combination of heat transfer destinations. The same can be applied to the thermal management system.

  In the above embodiment, the medium storage amount Qm is obtained based on the pressure Pl of the heat transfer medium in the heat transfer destination, but the medium storage amount Qm can also be obtained from the detected values of other parameters. . For example, if the temperature of the heat transfer medium in the heat transfer destination is known, the pressure can be obtained from the saturated water vapor curve. Therefore, the medium storage amount Qm can also be obtained from the temperature of the heat transfer medium in the heat transfer destination.

In the above embodiment, the heat transfer medium is stored in all of the heat transfer destinations where the heat transfer is stopped. However, the heat transfer medium may be stored only in a part of the heat transfer destinations.
In the above embodiment, water is used as the heat transfer medium, but fluid other than water may be used as the heat transfer medium.

  In the above embodiment, the heat recovered from the exhaust of the engine 1 is supplied to the heat transfer destination. However, in the heat management system using other waste heat as the heat supplied to the heat transfer destination, The present invention can be similarly applied.

  In the above embodiment, the vapor of the heat transfer medium is sent to the heat transfer destination, and the heat transfer medium is condensed at the heat transfer destination and recovered as a liquid. That is, in the above-described embodiment, the recovery device that recovers the heat supplied to the heat transfer destination is configured as a boiling device that applies heat to the heat transfer medium and vaporizes the heat transfer medium. The heat transfer destination is configured as a condenser that robs the liquefied heat transfer medium. However, the present invention can be similarly applied to a heat management system that circulates a heat carrier medium in a liquid state or in a gas state.

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Exhaust pipe, 3 ... Exhaust heat recovery device (boiler), 4 ... Steam piping, 5 ... Liquid piping, 6 ... Heater (conveyance destination, condenser), 7 ... Engine warmer (conveyance destination, condensation) 8) Transmission, 9 ... Mission warmer (conveyance destination, condenser), 10 ... Regenerator (conveyance destination, condenser), 11 ... Rankine cycle system (conveyance destination, condenser), 12 ... Heater, 13 ... Expander, 14 ... condenser, 15 ... pump, 16 ... electronic control unit, 6i, 7i, 9i, 10i, 11i ... IN valve, 6o, 7o, 9o, 10o, 11o ... OUT valve, 6s, 7s, 9s, 10 s, 11 s ... pressure sensor, 20 ... condenser, 21 ... steam line, 22 ... IN valve, 23 ... liquid line, 24 ... OUT valve.

Claims (6)

A heat management system for a vehicle that supplies heat to a plurality of heat transfer destinations installed in the vehicle through circulation of a heat transfer medium and can selectively switch the heat transfer destination for transferring heat from the plurality of heat transfer destinations. In
A heat management system for a vehicle, wherein the amount of circulation of the heat transfer medium is adjusted by storing the heat transfer medium in a heat transfer destination where heat transfer is suspended. The vehicle thermal management system according to claim 1, wherein a storage amount of the heat transfer medium in the heat transfer destination is estimated from a pressure of the heat transfer medium in the heat transfer destination. The vehicle thermal management system according to claim 1, wherein the storage amount of the heat transfer medium in the heat transfer destination is estimated from the temperature of the heat transfer medium in the heat transfer destination. The recovery unit that recovers the heat supplied to the heat transfer destination is configured as a boiling device that applies heat to the heat transfer medium to vaporize the heat transfer medium, and the heat transfer destination receives heat from the heat transfer medium. The vehicle thermal management system according to claim 1, wherein the heat management system is configured as a condenser that liquefies the heat transfer medium. The vehicle thermal management system according to claim 4, wherein water is used as the heat transfer medium. The vehicle thermal management system according to claim 4, wherein the recovery unit is configured to recover heat from engine exhaust.

Images