JP2006204014A - Electrical equipment and fuel cell stack - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the size of electrical equipment so constructed that it includes a fuel cell stack and a motor. <P>SOLUTION: The electrical equipment includes the fuel cell stack constructed by alternately disposing the unit cells and separators of a fuel cell, and a rotor rotatably inserted into the fuel cell stack. The electrical equipment is so constructed that the rotor is rotated using the fuel cell stack as a stator. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electrical device. This electrical device is a fusion of a fuel cell stack and an electric motor.

A fuel cell has a solid polymer between a fuel electrode (also referred to as a hydrogen electrode when hydrogen is used as a fuel electrode) and an air electrode (also referred to as an oxygen electrode or oxygen electrode because oxygen is a reactive gas). It is configured such that a solid electrolyte such as an electrolyte membrane is sandwiched.
In the fuel cell having such a configuration, the fuel gas is supplied to the fuel electrode side (anode) and the oxidizing gas is supplied to the air electrode side. As a result of the progress of the electrochemical reaction, an external load circuit is connected from the fuel electrode side. Electrons can flow to the air electrode side via. That is, the hydrogen ions obtained at the fuel electrode (anode) move in the electrolyte membrane to the air electrode (cathode) side with water in the form of oxonium ions (H ₃ 0 ⁺ ). Electrons obtained with the generation of hydrogen ions at the fuel electrode (anode) flow to the air electrode (cathode) side through the external load circuit to reduce oxygen in the oxidizing gas (including air). Produce water. A fuel cell can extract electrical energy through a series of electrochemical reactions.

  Since such a fuel cell unit cell alone cannot provide sufficient power, a so-called stack in which a large number of unit cells are stacked in series is used. In such a stack, a separator is interposed between the unit cells in order to secure a flow path for oxidizing gas and fuel gas and to cool the stack.

On the other hand, the electric power generated by the fuel cell stack may be used to drive the motor. In other words, the fuel cell stack and the motor are provided as separate electrical devices, and the electric power of the fuel cell stack is supplied to the motor through the electrical wiring and the controller in the middle (see Patent Document 1 and the like). ).
No. 2004-192996

The present inventor has paid attention to the fact that fuel cells will be widely used as a future power supply means, and has repeatedly studied an electric device for driving a motor.
Problems to be solved in such an electric device include a reduction in size and weight of the device.
It is difficult to rotate the motor with sufficient output only by the power generation capability of the current unit cell of the fuel cell. Therefore, it is necessary to apply sufficient power to the motor by connecting the unit cells in series. Therefore, a practical fuel cell has a so-called stack structure in which a plurality of unit cells are arranged. Therefore, the fuel cell device is increased in size. On the other hand, since a motor has a stator and a rotor as basic elements, there is a limit to downsizing the apparatus except for a special motor such as a linear motor.
Accordingly, an object of the present invention is to reduce the size of an electric device that drives a motor with the output of a fuel cell.

In order to achieve the above object, the first aspect of the invention employs the following configuration. That is,
A fuel cell stack in which unit cells and separators of the fuel cell are alternately arranged;
A rotor rotatably inserted into the fuel cell stack,
The rotor rotates with the fuel cell stack side as a stator,
An electrical device.
According to the electric device configured as described above, since the fuel cell stack and the stator of the motor are used, the electric device as a whole can be reduced in size and weight.

According to the invention of the second aspect, the separator of the fuel cell stack constitutes the stator.
As a result, the number of parts can be reduced, and an inexpensive electric device can be provided.

According to the invention of the third aspect, the separator is made of a magnetic material such as iron, and a winding is attached to the separator to constitute a stator of a rotary armature motor.
The separators are generally insulated by a solid electrolyte membrane. Therefore, the separator in the fuel cell stack has the same structure as the insulating laminated iron plate in a general electric motor. Therefore, eddy current loss is reduced, and high performance can be ensured when the electric device is viewed as a motor.

According to the invention of the fourth aspect, a winding is attached to the rotor side, and the separator constitutes a stator of a rotating field motor.
The electric device having such a configuration is suitable when a characteristic as a rotating field motor such as a DC motor is required.

According to the fifth aspect of the invention, the rotor is rotated by the electric power generated by the fuel cell stack.
By rotating the rotor with the electric power generated in the fuel cell stack, the configuration of the electric device can be simplified as much as possible.

The invention of the sixth aspect is defined as follows. That is,
A fuel cell stack in which unit cells and separators of a fuel cell are alternately arranged,
A fuel cell stack, wherein a through-hole for receiving a rotor is formed in an arrangement direction of the unit cells and the separator.
The invention of the sixth aspect specifies the fuel cell stack constituting the invention of the first aspect. By employing the fuel cell stack having such a configuration, the electric device can be reduced in size and weight.

According to a seventh aspect of the invention, in the sixth aspect of the invention, the separator is made of a magnetic material and a winding receiving portion is formed thereon.
Thereby, a separator functions as a stator of an induction motor.

The invention of the eighth aspect is defined as follows. That is,
An electric device characterized in that a motor rotor is present in the fuel cell stack.
According to the electric device configured as described above, the entire electric device can be reduced in size and weight.

As the unit cell of the fuel cell, one having a general configuration in which an electrolyte membrane is sandwiched between an air electrode and a fuel electrode can be adopted. Each of the air electrode and the fuel electrode includes a catalyst layer and a diffusion layer in contact with the electrolyte membrane.
The separator is interposed between the unit cells and includes an air passage for supplying air to the air electrode and a fuel gas passage for supplying fuel gas (hydrogen gas) to the fuel electrode. The separator can also be formed with a flow path for circulating a cooling medium (such as water) for cooling the fuel cell stack.
The material of the separator is not particularly limited, but when the separator itself is used as a stator, it is preferably formed of a magnetic material such as silicon steel. This is because by winding the winding directly on the separator, this can be used as an iron core. By attaching a winding to the separator, a rotary armature motor such as an induction motor can be configured.
When winding the winding directly on the separator, it is preferable to provide a winding receiving portion on the rotor facing surface of the separator. That is, the rotor facing surface of the separator body provided with the air flow path and the fuel gas flow path is closed. Therefore, the winding receiving portion is projected from the rotor facing surface. The winding receiver may be integral with the separator body or may be a separate body.

  A separator and a stator can also be made into a different body. In this case, a hole is provided in the fuel cell stack, and the stator is inserted into this hole. The stator in this case can employ a general-purpose electric motor, and the fuel cell stack serves as a casing.

The rotor is arbitrarily selected according to the type of electric motor. In a rotating field motor such as a DC motor, the rotor is wound.
From the viewpoint of weight balance, it is preferable to attach the rotor to the central portion of the fuel cell stack. It is also possible to attach more than one rotor to the fuel cell stack.

Examples of the present invention will be described below.
As shown in FIG. 1, the electric apparatus 1 according to the embodiment includes a fuel cell stack 10 and an electric motor unit 20. FIG. 2 is a cross-sectional view schematically showing the configuration of the electric device 1.
The fuel cell stack 10 has a configuration in which general-purpose fuel cell unit cells 11 and separators 16 are alternately stacked. Reference numerals 17 and 18 denote both end covers of the fuel cell stack. The unit cell 11 has a configuration in which the solid electrolyte membrane 12 is sandwiched between the fuel electrode 13 and the air electrode 14, and the separator 16 supplies air to the fuel gas passage for supplying the fuel gas to the fuel electrode 13 and the air electrode 14. An air flow path is formed.

  In the fuel cell stack 10, through holes are formed in the arrangement direction of the unit cells 11 and the separators 16, and a cylindrical stator 21 is fitted into the through holes. The peripheral wall of the through hole in the stack 10 closes the functional portions of the unit cell 11 and the separator 16 so that fuel gas or the like does not leak to the electric motor unit 20 side.

A detailed configuration of the stator 21 is shown in FIG. The stator 21 includes an iron core portion 25 and a winding portion 29 that are inserted into the fuel cell stack 10. The iron core portion 25 has a cylindrical yoke 26 and a winding receiving portion 27 protruding from the yoke 26, and the winding receiving portion 27 serves as a magnetic pole. The iron core portion 25 can be formed of a general magnetic material as an iron core such as silicon steel.
A winding wire 29 is formed by overlappingly winding a copper wire around the winding receiving portion 27. As the winding method of the copper wire, an arbitrary method is selected from short-pitch winding, full-pitch winding, distributed winding, concentrated winding, and the like according to characteristics required for the motor unit 20.

For the rotor 23, a general-purpose configuration such as a cage shape or a winding shape is arbitrarily selected according to characteristics required for the electric motor unit 20. In a DC motor or the like, the rotor is also wound.
A shaft 24 is inserted into the rotor 23. The rotor 23 and the shaft 24 are coupled by a general-purpose method.

According to the electric device 1 configured as described above, the fuel cell stack 10 includes a motor part. Thereby, size reduction and weight reduction are achieved as a whole apparatus.
By supplying the electric power generated by the fuel cell stack 10 to the electric motor unit 20, the configuration of the apparatus is simplified and an inexpensive electric apparatus is obtained. Of course, the power supplied to the electric motor unit 20 can be supplied from other than the fuel cell stack 10.

FIG. 4 shows an electric apparatus according to another embodiment. The same elements as those in FIG. 2 are denoted by the same reference numerals, and the description thereof is omitted.
In this embodiment, the winding receiving portion 37 is protruded from the separator 16 of the fuel cell stack 10, and the separator 16 itself is used as the stator of the electric motor. In this case, the separator 16 is formed of a magnetic material such as silicon steel. Since the separator 16 is electrically insulated by the insulating solid electrolyte membrane 12, it has the same kind of configuration as an insulating laminated plate of a general-purpose electric motor. Therefore, eddy current loss can be reduced and high efficiency can be obtained as an electric motor.
In addition, the code | symbol 161 in a figure is a fuel channel | path, and the code | symbol 162 is an air flow path. As shown in FIG. 4, the motor unit facing surface of the separator 16 is closed, and leakage of fuel gas and air is prevented. Also in the unit cell 11, it is preferable that the motor unit facing surface is sealed.

  The present invention is not limited to the description of the embodiments and examples of the invention described above. Various modifications may be included in the present invention as long as those skilled in the art can easily conceive without departing from the description of the scope of claims.

FIG. 1 is a perspective view of an electric apparatus according to an embodiment of the present invention. It is sectional drawing which shows the structure of an electric device typically similarly. It is a perspective view which similarly shows the structure of a fuel cell stack and a stator. It is sectional drawing which shows the stator structure of another Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric apparatus 10 Fuel cell stack 11 Unit cell 20 Electric motor part 21 Stator 22 Rotor 27 Winding receiving part

Claims (8)

A fuel cell stack in which unit cells and separators of the fuel cell are alternately arranged;
A rotor rotatably inserted into the fuel cell stack,
The rotor rotates with the fuel cell stack side as a stator,
An electrical device.   The electric device according to claim 1, wherein the separator of the fuel cell stack constitutes a stator.   The electric device according to claim 2, wherein the separator is made of a magnetic material, and a winding is attached to the separator to constitute a stator of a rotary armature motor.   The electric device according to claim 2, wherein a winding is attached to the rotor side, and the separator constitutes a stator of a rotating field type electric motor. The electric device according to claim 1, wherein the rotor is rotated by electric power generated by the fuel cell stack. A fuel cell stack in which unit cells and separators of a fuel cell are alternately arranged,
A fuel cell stack, wherein a through-hole for receiving a rotor is formed in an arrangement direction of the unit cells and the separator. The fuel cell stack according to claim 6, wherein the separator is made of a magnetic material, and a winding receiving portion is formed on the separator. An electric device characterized in that a motor rotor is present in the fuel cell stack.

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