JP2007060840A - Vehicle powered by fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle powered by fuel cell for suppressing a temperature rise of compressed air discharged from a compressor for supplying air to a fuel cell without a dedicated cooling system. <P>SOLUTION: The vehicle powered by fuel cell is provided with the fuel cell 11 for generating power using an electrochemical reaction between a fuel gas and an oxidant gas, the compressor 1 for supplying the compressed air as the oxidant gas to the fuel cell 11, a sound absorber 3 as a compressed air circuit component installed on a compressed air circuit between the compressor 1 and the fuel cell 11, and a radiator 8 for implementing a heat exchange between outside air and a fluid for cooling a component such as the fuel cell 11 to be cooled. At least one of the compressor 1 and the sound absorber 3 faces the radiator 8 viewed from the front at an installed location. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel cell vehicle, and relates to a technique for reducing the temperature of compressed air discharged from a compressor without using a dedicated cooling system.

  A fuel cell vehicle is equipped with a compressor for supplying an oxidant gas (cathode gas) containing oxygen to the fuel cell. The air compressed by the compressor becomes high temperature due to its compression ratio. In particular, since the heat resistant temperature of the polymer electrolyte membrane is about 90 ° C. in the polymer fuel cell, it is used in a heat exchanger (intercooler). It is cooled and supplied to the fuel cell. In the intercooler, the compressed air is generally cooled by exchanging heat with cooling water.

However, in a fuel cell vehicle, heat is generated with the power generation of the fuel cell. However, in the fuel cell, it is preferable to keep the fuel cell during power generation at a predetermined temperature (for example, around 70 ° C.) from the viewpoint of power generation performance, and cooling is necessary. Become. In addition, in a fuel cell vehicle, there are many parts that require cooling, such as a motor for driving a vehicle, an inverter that supplies electric power to the motor, a compressor motor that drives the compressor, and an inverter that supplies electric power to the motor. A large radiator is required as compared with an internal combustion engine automobile (see, for example, Patent Document 1).
JP 2002-298896 (pages 5 to 7, FIG. 1)

  However, increasing the size of the radiator causes an increase in the weight of the radiator and cooling water, resulting in a rebound such as an increase in vehicle weight and fuel consumption and a decrease in vehicle acceleration. Moreover, the power consumption of the pump for circulating the cooling water increases, and there is a problem that fuel consumption increases.

  Therefore, the present invention has been made to solve the above-described problems, and in a fuel cell vehicle equipped with a fuel cell system, the temperature of compressed air discharged from a compressor that supplies air to the fuel cell is exclusively used. An object of the present invention is to provide a fuel cell vehicle that can be reduced without using the above cooling system.

  The present invention relates to a fuel cell that generates electricity by an electrochemical reaction between a fuel gas and an oxidant gas, a compressor that supplies compressed air to the fuel cell as an oxidant gas, and a compression between the compressor and the fuel cell. The fuel cell vehicle includes a compressed air circuit component installed on an air circuit, and a radiator that exchanges heat between a fluid that cools a component that needs cooling, such as the fuel cell, and the outside air.

  In the fuel cell vehicle of the present invention, at least one of the compressor and the compressed air circuit component is disposed at a position facing the radiator when viewed from the front of the vehicle.

  According to the fuel cell vehicle of the present invention, the compressor and the compressed air circuit component are arranged at positions facing the radiator, so that the radiator downstream air blown by the radiator fan is supplied to the compressor and the compressed air circuit. The hot compressed air can be cooled by hitting the parts. Therefore, according to the fuel cell vehicle of the present invention, high-temperature compressed air discharged from the compressor can be cooled without using a dedicated cooling system.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

“First Embodiment”
FIG. 1 is a schematic plan view of the fuel cell vehicle according to the first embodiment as viewed from above the motor room, and FIG. 2 is a schematic side view of the fuel cell vehicle of FIG. 1 as viewed from the side.

  As shown in FIGS. 1 and 2, the fuel cell vehicle according to the present embodiment includes a fuel cell 11 that generates electricity by an electrochemical reaction between a fuel gas and an oxidant gas, and an oxidant that compresses air compressed into the fuel cell 11. Compressor 1 supplied as gas, silencer 3 which is a compressed air circuit component installed on a compressed air circuit between compressor 1 and fuel cell 11, and components such as fuel cell 11 that require cooling And a radiator 8 for exchanging heat between the fluid for cooling the air and the outside air.

  The compressor 1 is driven by a compressor drive motor 2, sucks outside air through an air cleaner (not shown), compresses the sucked air, and applies a high temperature to a silencer 3 which is one of compressed air circuit components. Feed in compressed air. The silencer 3 is connected to the compressor 1 and reduces noise and vibration of compressed air sent from the compressor 1.

  Thereafter, the compressed air passes through a compressed air pipe 4 connecting the silencer 3 and the fuel cell 11 and is cooled to a predetermined temperature by an aftercooler 7 disposed in the middle of the route. The cooled oxygen-containing oxidant gas (cathode gas) is humidified by the humidifier 10 and then supplied to the fuel cell 11.

  The compressor 1, the compressor drive motor 2, and the silencer 3 are disposed in a motor room such that the compressor 1, the compressor drive motor 2, and the silencer 3 are disposed at positions facing the radiator 8 when viewed from the front of the vehicle to the rear of the vehicle. It is supported by. That is, the compressor 1 and the compressor drive motor 2 are opposed to the radiator 8 by fixing the compressor drive motor 2 to the tip of the compressor mounting arm 1a protruding from the wheel drive motor 5 toward the radiator 8. Are arranged to be. Similarly, the muffler 3 is also arranged so as to face the radiator 8 by being fixed to the tip of the radiator mounting arm 1b protruding from the wheel drive motor 5 toward the radiator 8.

  A reduction gear 6 is connected to the output shaft of the wheel drive motor 5 to reduce the motor rotation speed and convert it to wheel rotation speed.

  In this way, if the compressor 1 and the silencer 3 are disposed at a position facing the radiator 8 when viewed from the front of the vehicle, the air compressed by the compressor 1 and heated to a high temperature is attached to the center of the radiator 8. It is possible to cool by the air blown by the radiator fan 9. That is, since the radiator downstream air blown by the radiator fan 9 hits the compressor 1 and the silencer 3, the high-temperature compressed air can be cooled. Further, since not only the compressor 1 and the silencer 3 but also the compressed air pipe 4 constituting the compressed air circuit component is cooled, the compressed air from the compressor 1 can be further cooled.

  Moreover, in this Embodiment, it compresses in the downstream part of the silencer 3 by directing the flow of the compressed air which came out of the compressor 1 (indicated by the arrow in FIG. 1) in the same direction as the cooling water flowing in the radiator 8. It becomes possible to cool the compressed air cooled from the temperature immediately after the machine discharge with the downstream air that has passed through the radiator 8 through which the cooling water most cooled by the radiator 8 flows, and the heat exchange efficiency is improved. In other words, compression is performed by setting the flow direction of the compressed air flowing through the compressor 1 and the compressed air circuit components (the silencer 3 and the compressed air pipe 4) to be substantially the same as the flow direction of the cooling water flowing through the radiator 8. Since the temperature difference between the temperature of the air and the cooling water flowing in the radiator 8 can be maximized over the entire area, the heat exchange efficiency can be improved.

  FIG. 6 shows the relationship between the cooling water flowing through the radiator and the air temperature. As can be seen from FIG. 6, the cooling water flowing in the radiator 8 has a structure in which the temperature is lowered by exchanging heat with the outside air having a low temperature. Therefore, as shown by the solid line, the cooling water flows downstream from the upstream side. It has a temperature gradient that decreases toward the side. Therefore, the temperature of the outside air that has passed through the radiator 8 is lower on the downstream side than on the upstream side.

  In order to maximize the temperature difference between the temperature of the compressed air and the cooling water flowing in the radiator 8, the value obtained by integrating the temperature difference with the compressed air temperature from the inlet to the outlet of the radiator 8 can be maximized. It means that.

  Further, in the present embodiment, the compressor 1 and the compressed air circuit components (the silencer 3 and the compressed air pipe 4) are installed in front of the vehicle of the wheel drive motor 5 so that the compressor 1 and the compressed air circuit components can be used. By arranging the radiated noise in a direction further away from the passenger compartment and by shielding the noise by the wheel drive motor 5, the noise in the passenger compartment can be reduced.

  Further, in the present embodiment, the silencer 3 as a silencer member is installed in the compressed air circuit disposed at a position facing the radiator 8, so that the noise of the compressed air discharged from the compressor 1 is reduced. In addition, the cooling can be performed more on the surface area of the compressor 1. That is, the temperature of the air discharged from the compressor 1 is higher than the temperature of the air that passes through the radiator 8 and impinges on the silencer 3, and therefore, between the air that has passed through the radiator 8 and the surface of the silencer. Thus, heat exchange is performed, that is, the air discharged from the compressor 1 can be cooled.

“Second Embodiment”
FIG. 3 is a schematic front view of the fuel cell vehicle according to the second embodiment as viewed from the front of the vehicle toward the rear of the vehicle.

  In the fuel cell vehicle according to the present embodiment, two silencers 3A and 3B having different sizes are arranged at positions facing the radiator 8 when viewed from the front of the vehicle, as in the first embodiment. The apparatus 3A is directly installed at the discharge port 11 of the compressor 1.

  That is, in this embodiment, two silencers 3A and 3B having different sizes are used, and one of these silencers 3A (hereinafter referred to as the first silencer 3A) having a small volume is used as the discharge port of the compressor 1. 11 is connected directly without using a pipe, and the other silencer 3B (hereinafter referred to as the second silencer 3B) is connected to the first silencer 3A via the connecting pipe 12, and the first silencer 3A and The second silencer 3 </ b> B is disposed at a position facing the radiator 8 in front of the wheel drive motor 5.

  That is, in the present embodiment, the first silencer 3A having a small volume with a relatively high frequency that can be silenced is directly connected to the discharge port 11 of the compressor 1, and the other volume is large and a sound with a relatively low frequency is produced. The second silencer 3B that can mute is connected by a bellows-like connecting rod 12 that can absorb the variation in assembly, and these are arranged on the vehicle front side above the wheel drive motor 5 at a position facing the radiator 8. Yes.

  According to the fuel cell vehicle of the present embodiment, by providing the silencer 3 directly at the discharge port 11 of the compressor 1, not only piping for connecting the silencer 3 and the compressor 1 is required, Since the noise can be immediately reduced at the place where the radiated sound is most likely to be generated (where it comes out of the compressor 1), the noise in the passenger compartment can be reduced. Moreover, by making the cross-sectional area of the silencer 3 larger than the cross-sectional area of the pipe, the amount of heat radiation at the hottest portion can be increased, and the compressed air temperature can be efficiently reduced.

  In addition, according to the fuel cell vehicle of the present embodiment, since the surface area can be increased by installing two or more silencers 3, the cooling effect in the air after the radiator is increased, and the cooling performance is further improved. This can be further improved.

  Moreover, according to the fuel cell vehicle of the present embodiment, it is possible to reduce noise of different frequencies by installing two or more silencers 3 having different sizes.

“Third Embodiment”
FIG. 4 is a schematic front view of the fuel cell vehicle according to the third embodiment as viewed from the front of the vehicle toward the rear of the vehicle.

  In the fuel cell vehicle according to the present embodiment, the discharge port 11 of the compressor 1 and the silencer 3 that is a compressed air circuit component are arranged at positions that do not face the fan drive motor 13 of the radiator fan 9 that cools the radiator 8. ing. That is, in this fuel cell vehicle, the discharge port 11 of the compressor 1, the first silencer 3A, and the second silencer 3B are arranged at a position that does not face the fan drive motor 13 provided in the center of the radiator fan 9. ing.

  According to the fuel cell vehicle of the present embodiment, when the compressor 1 and the compressed air circuit component are disposed at a position facing the radiator 8, it faces the fan drive motor 13 installed at the center of the radiator fan 9. By not doing so, since air with a larger air volume can be applied to the discharge port 11 and the first silencer 3A and the second silencer 3B of the compressor 1, the cooling performance can be greatly improved.

“Fourth Embodiment”
FIG. 5 is a flowchart showing the rotation speed control of the radiator fan in the fuel cell vehicle according to the fourth embodiment.

  In the fuel cell vehicle according to the fourth embodiment, the rotational speed control of the radiator fan 9 installed in the radiator 8 is added to the air volume necessary for heat exchange of the cooling water, and the air volume necessary for cooling the compressed air is also included. Control.

  Specifically, first, in step S1, the compressed air temperature (Tc) discharged from the compressor 1 is measured. In the process of the next step S2, it is determined whether or not the measured compressed air temperature is higher than a certain threshold value (Tx). If the compressed air temperature is lower than the threshold value in the determination process of step S2 (in the case of NO), the rotation speed of the radiator fan 9 (in FIG. 5) required for temperature control of the cooling water is processed in the next step S3. In the flowchart, it is described as the number of rotations of the radio fan).

  Further, when the compressed air temperature is higher than the threshold value in the determination process in step S2 (in the case of YES), in the next step S4, the compressed air temperature is set to a certain threshold value or less from the outside air temperature and the radiator inlet water temperature. The number of revolutions of the radiator fan 9 necessary for the calculation is calculated.

  When the processing of step S3 and the processing of step S4 are completed, in the next processing of step S5, the larger one of the fan rotation speeds calculated from step S3 and step S4 is selected and the radiator fan 9 is commanded. Send.

  As described above, according to the present embodiment, since the rotational speed of the radiator fan 9 can be controlled in accordance with the temperature of the compressed air discharged from the compressor 1, the operation with the best efficiency of the entire fuel cell system is performed. Can be realized.

  Further, in the fuel cell vehicle according to the present embodiment, the rotation speed of the radiator fan 9 is controlled not only by the air volume required from the cooling system but also by taking into consideration the air volume necessary for cooling the compressed air. This makes it possible to efficiently operate the fuel cell vehicle as a whole, for example, by reducing the amount of cooling water to be used and reducing the power consumption of the cooling water pump.

  Although specific embodiments to which the present invention is applied have been described above, the above-described embodiments are examples of the present invention, and the present invention is not limited to these embodiments.

It is a schematic plan view when the fuel cell automobile of the first embodiment is viewed from above the motor room. It is a schematic side view when the fuel cell vehicle of FIG. 1 is seen from the side. It is a schematic front view when the fuel cell vehicle of 2nd Embodiment is seen toward the vehicle rear from the vehicle front. It is a schematic front view when the fuel cell vehicle of 3rd Embodiment is seen toward the vehicle rear from the vehicle front. It is a flowchart which shows the rotation speed control of the radiator fan in the fuel cell vehicle of 4th Embodiment. It is a characteristic view which shows the relationship between the cooling water which flows the inside of a radiator, and air temperature.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Compressor 2 ... Compressor drive motor 3 ... Silencer (compressed air circuit components)
3A ... First silencer (compressed air circuit component)
3B ... 2nd silencer (compressed air circuit parts)
4 ... Compressed air piping 5 ... Wheel drive motor 6 ... Reducer 7 ... After cooler 8 ... Radiator 9 ... Radiator fan 10 ... Super humidifier 11 ... Fuel cell 13 ... Fan drive motor

Claims (9)

A fuel cell that generates electricity by an electrochemical reaction between a fuel gas and an oxidant gas; a compressor that supplies compressed air to the fuel cell as an oxidant gas; and a compressed air circuit between the compressor and the fuel cell. In a fuel cell vehicle comprising a compressed air circuit component to be installed, and a radiator that exchanges heat between a fluid that cools a component that requires cooling, such as the fuel cell, and outside air,
At least one component of the compressor and the compressed air circuit component is disposed at a position facing the radiator when viewed from the front of the vehicle. The fuel cell vehicle according to claim 1,
The fuel cell vehicle, wherein the discharge port of the compressor and the compressed air circuit component are disposed at a position not facing a fan drive motor of a radiator fan that cools the radiator. The fuel cell vehicle according to claim 1 or 2,
Compressed air discharged from the compressor flows in substantially the same direction as the flow direction of cooling water flowing in the radiator in a compressed air circuit component disposed at a position facing the radiator. Car. A fuel cell vehicle according to at least one of claims 1 to 3,
The fuel cell automobile, wherein the compressor and the compressed air circuit component are supported in front of a drive motor unit disposed in a motor room. A fuel cell vehicle according to at least one of claims 1 to 4,
A fuel cell vehicle, wherein a silencer member is installed in a compressed air circuit disposed at a position facing the radiator. A fuel cell vehicle according to at least one of claims 1 to 5,
A fuel cell vehicle, wherein a silencer member is directly installed at a discharge port of a compressor disposed at a position facing the radiator. The fuel cell vehicle according to claim 6,
At least two or more of the sound deadening members are arranged. A fuel cell vehicle. The fuel cell vehicle according to claim 7,
A fuel cell vehicle characterized in that the two sound deadening members have different sizes. A fuel cell vehicle according to at least one of claims 1 to 8,
A fuel cell vehicle characterized by controlling the rotational speed of a radiator fan installed in the radiator in addition to an air volume necessary for heat exchange of cooling water and an air volume necessary for cooling compressed air.

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