JP2003259685A - Electric motor and control method of electric motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently extract power from a battery having a low power generation voltage and to reduce power loss. <P>SOLUTION: An electric motor having the battery and a motor section is provided with a battery 11 having a battery voltage of 4 volts or lower, a rotor 12 around which a field winding 1 is wound, an armature winding 13, brushes 15a, 15b, and the motor section having a commutator 16. Focusing general characteristics of a separately excited motor, a ratio of field power to the maximum power of the armature is set at a value in a range smaller than 1/10 e.g. a conventional general range, especially 1/100-1/10, and the input voltage of a field control circuit is set at a value higher than that of the voltage of the armature winding. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric motor and an electric motor control method, and more particularly to an electric motor and an electric motor control method capable of supplying electric power efficiently even if the number of unit cells forming a battery is reduced.

[0002]

2. Description of the Related Art In recent years, attention has been paid to electric vehicles powered by an electric motor that uses clean electric energy that does not generate Co ₂ or No _x , while resource issues and environmental issues are being highlighted. As electric energy widely used in such electric vehicles, nickel-cadmium batteries, nickel-hydrogen batteries, lithium-ion batteries, and lead-acid batteries, which can obtain relatively large electric power, are frequently used. However, since these batteries contain a finite amount of active material, the discharge life is reached and the discharge capacity is lost if the active material is lost. In addition, since the weight of the battery itself increases with respect to the power capacity, it lacks versatility.

On the other hand, the fuel cell has an advantage that power generation can be continued without exhaustion as long as hydrogen and oxygen are supplied to both electrodes. Further, unlike the heat engine using the Carnot cycle, the fuel cell directly converts the change in free energy of the chemical reaction into electric energy, so that energy can be obtained at a conversion efficiency of 75 to 80% even at a low temperature.

A general fuel cell is composed of a negative electrode active material, a negative electrode, an electrolyte, a positive electrode and a positive electrode active material, and uses hydrogen or methanol as the negative electrode active material and oxygen as the positive electrode active material. As a result of the chemical reaction, only water and heat are generated in addition to electric energy, and it is attracting attention because it has no environmental impact. Also, the output power per unit weight of the fuel cell is 6600 Wh / kg (weight of hydrogen), which is very large, compared to about 150 Wh / kg (watt hour / kg) of the lithium-ion battery. Is.

Fuel cells are classified into phosphoric acid fuel cells (PAFC) and molten carbonate fuel cells (MC) depending on the type of electrolyte.
FC), solid oxide fuel cell (SOFC), polymer electrolyte fuel cell (PEFC), etc. The fuel cell 100 shown in FIG. 14 is a solid electrolytic fuel cell, and as a general configuration, a solid polymer electrolyte membrane 101, an electrode catalyst 102, an oxygen electrode (positive electrode) 103, and a fuel electrode (negative electrode) 104. And a separator 105, and both sides of the solid polymer electrolyte membrane 101 located in the center are sandwiched by an electrode catalyst 102 made of carbon fiber to which platinum particles are adhered, and further both sides are provided with an oxygen electrode 103 and a fuel electrode 104.
It is sandwiched between and and constitutes one cell. In general, hydrogen is used as a fuel, so that the electrode 1
04 is referred to as a hydrogen electrode 104.

As the solid polymer electrolyte membrane 101, one having a high ionic conductivity and capable of containing a reaction product as an ion is used. A gas flow path is formed in the oxygen electrode 103 and the hydrogen electrode 104. The solid polymer electrolyte membrane 101 has a thickness of about 20 μm to 50 μm, but the oxygen electrode 103 is provided with hydrogen and oxygen channels.
When the hydrogen electrode 104 and the separator are combined, 1
The thickness of the cell is 3 to 6 mm.

In this fuel cell 100, when oxygen and hydrogen are supplied to the gas flow path, the hydrogen gas releases electrons due to the catalytic action of platinum to become hydrogen ions, and passes through the solid polymer electrolyte membrane 101. Move to the oxygen side.

For example, in a fuel cell using hydrogen and oxygen as active substances, the theoretical value of the generated voltage per cell is 1.23 V, but when the voltage is taken out from the electrode, it depends on the influence of the catalyst. The potential difference that can be actually taken out is 1 due to the voltage drop due to activation polarization, resistance of the electrolyte and resistance polarization between the electrolyte and the electrode, and diffusion polarization accompanying transfer substances such as gas and water. It decreases to about 0.6 to 0.7 V per cell. Therefore,
In order to secure the voltage according to the application (electric motor), it is necessary to obtain a desired voltage by stacking a plurality of cells shown in FIG. 14 and forming a stack structure as shown in FIG. In the fuel cell stack structure shown in FIG.
Fuel cells 100 _{1 to} 100 _n are stacked and current collector plates 10 are provided at both ends.
6, 107 are provided, and a hydrogen gas flow path is further provided.

The electric motor rarely continues to rotate at a constant voltage, and is generally used by controlling the torque and the rotating direction. Therefore, a circuit for controlling the operation of the electric motor, such as a voltage conversion circuit or a frequency conversion circuit for converting the frequency from DC to AC, is provided between the fuel cell and the electric motor.

[0010]

As described above, the fuel cell has the advantage that energy can be obtained with a high conversion efficiency of 75 to 80%, but the voltage provided between the fuel cell and the electric motor. There is a drawback that the energy loss in the conversion circuit and the frequency conversion circuit is so large that it cannot be ignored.

As a voltage conversion circuit and a frequency conversion circuit used in an electric motor having a fuel cell, in order to minimize the loss of each of these circuits, switching elements as shown in FIGS. 16 and 17 are turned on and off. And a circuit utilizing the above is used as the switching element, and the switching element has 0.4V to
A semiconductor power device is used because it has a forward voltage characteristic of about 1V. However, if the semiconductor power element is interposed between the battery and the electric motor, a voltage drop and power loss occur depending on the number of elements. For example, if there is a forward voltage drop of 0.4V in the power element and the output voltage of the battery is 0.7V, the voltage applied to the motor is
Theoretically, it becomes 0.2V. In this, 2 power elements
With the circuit used in series, a sufficient voltage cannot be taken out.

In the fuel cell, since it is desirable that the forward loss of the semiconductor element be 5% or less mainly considering heat generation and the like, a voltage of 8 V or more has been used for the control circuit.

That is, in the conventional fuel cell, the desired voltage is obtained by stacking a plurality of unit cells in which a required voltage can be sufficiently taken out in consideration of the control voltage in advance. It was

However, from the viewpoint of energy loss,
It is desirable to reduce the number of cells in series, especially
The fuel cell having the stack structure has a problem that the cell performance and cell characteristics of the entire main body are determined by the cell having the poorest performance. Furthermore, since the stack structure is a structure in which cells with gas channels are stacked,
There is also a problem that the structure becomes more complicated than other batteries, and the manufacturing cost increases accordingly.

On the other hand, the DC motor has a long history and various structures and their characteristics are well known, and a torque control method based on the structure has been established.

As an example of the control method, a separate excitation method is known. The separately excited motor is a DC motor in which the field and the armature are independently controlled, as shown in FIG. In the case of a separately excited motor, the rotation speed characteristic and the torque amount can be controlled by controlling the field current. From the viewpoint of ease of control, a method of fixing the field current and controlling the armature current is also used.

The electric motor is composed of a rotating portion and a fixed portion. However, the rotating portion has a structure other than that of using a permanent magnet for the rotating portion or an induction motor type structure adopting a cage winding structure. It is necessary to supply electric power to the rotating portion winding provided in the. A combination of a commutator and a brush device or a slip ring and a brush device is used to supply power to the rotating winding.
Here, in the combination of the commutator and the brush device, or in the combination of the slip ring and the brush device, a voltage drop of about 0.6 V occurs in this component portion, and therefore energy loss occurs when power is supplied to the rotor winding. In order to reduce and downsize the motor, a voltage of around 8V is still required for control.

As a specific example of a general moving device using a battery and an electric motor, there is an electric moving device such as an electric wheelchair. In this case, a battery having a limited generated voltage is connected in series to obtain a voltage of around 12V, and for easier control, a method of directly controlling the armature voltage with a switching regulator is used. .

However, when a battery is used as a power source in this way, it is generally unavoidable to serialize the battery to obtain a predetermined voltage or increase the size of the battery. In particular,
In the fuel cell, a stack structure (serialization of cells) to obtain a desired voltage while considering the energy loss even if the fuel storage part is downsized due to the improvement of the hydrogen storage
Since the point of adopting is unchanged, the complexity of the fuel cell structure cannot be solved under the current conditions.

Therefore, the present invention has been proposed in view of such conventional circumstances, and an electric motor and an electric motor capable of efficiently extracting electric power even from a battery having a small electric power loss and a low generated voltage. An object of the present invention is to provide a motor control method.

[0021]

In order to achieve the above-mentioned object, an electric motor according to the present invention has an armature having an armature winding to which armature power of a predetermined voltage or less is applied, and a field power. A field magnet having a field winding to be applied, a rotor provided with the field magnet, and a field current controller for controlling a field current flowing in the field winding are provided. The input voltage input to the field current control means is set higher than the voltage of the armature winding, and the ratio of the field power to the maximum value of the armature power is 1/100 to 1/10 of the armature power. It is characterized in that the number of rotations of the rotor is controlled by controlling the magnitude of the field current so that

Here, the armature has a power generation winding, and in this power generation winding, a regenerative current is obtained from the field when braking the rotation of the rotor. Further, this electric motor is equipped with a field power source for obtaining field power, and the field power source is charged with a regenerative current.

Further, when the fuel cell using hydrogen is used as the power source, it is provided with an electrolyzing means for electrolyzing the water discharged from the hydrogen cell, and the water is decomposed in the electrolyzing means using the regenerative current.

In order to achieve the above-mentioned object, the motor according to the present invention has an armature having an armature winding to which armature power of a predetermined voltage or less is applied, and a field to which field power is applied. A field having a magnetic winding, a rotor provided with the field, field current control means for controlling a field current flowing in the field winding, and an armature, a field and a rotor isolated from the outside. By transmitting a field current to the field winding from the fixed side power transmission transformer fixed to the case via the rotation side rotation side power transmission transformer fixed to the rotor. The field current control means constitutes a rotated non-contact motor section, and the input voltage input to the field current control means is set to be higher than the voltage of the armature winding, and the field power and the armature power are The magnitude of the field current so that the ratio with the maximum value is 1/100 to 1/10 of the armature power. And controlling the rotational speed of the rotor by controlling further the housing is characterized by filling the hydrogen gas as a refrigerant.

Here, the power source is preferably a fuel cell using hydrogen. In this case, the fuel cell and a part of the housing are spatially conducted to share hydrogen. Further, the fuel cell is wound around the outer peripheral surface of the housing.

Further, in order to achieve the above-mentioned object,
The control method of the electric motor according to the present invention makes the input voltage input to the field current control means larger than the voltage of the armature winding,
The rotation speed of the rotor is controlled by controlling the magnitude of the field current so that the ratio of the field power to the maximum value of the armature power is 1/100 to 1/10 of the armature power. It is characterized by having a field current control step.

At this time, a step of obtaining a regenerative current from the field when braking the rotation of the rotor is provided, and the field power supply for obtaining the field power by the obtained regenerative current is charged. In particular, if the power source is a fuel cell, an electrolysis step of electrolyzing water discharged from the fuel cell by a regenerative current can be provided.

Furthermore, in order to achieve the above-mentioned object, in the method of controlling a motor according to the present invention, the input voltage input to the field current control means is set higher than the voltage of the armature winding, and the field magnet is controlled. Field current control for controlling the rotation speed of the rotor by controlling the magnitude of the field current so that the ratio of the power to the maximum value of the armature power is 1/100 to 1/10 of the armature power. The method includes a step and a cooling step of cooling the non-contact motor unit with hydrogen gas filled in the housing.

At this time, if the power source is a fuel cell using hydrogen, the fuel cell and a part of the housing are spatially electrically connected to generate hydrogen gas between the fuel cell and the non-contact motor section. You may circulate.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION An electric motor shown as an embodiment of the present invention is an electric motor for converting electric power into mechanical force and has an armature winding to which armature electric power of a predetermined voltage or less is applied. And the ratio of the maximum value of the field power is 1 / of the armature power
A field current control circuit that executes an operation of controlling the voltage to be 10 or less at a predetermined voltage or more, and a field having a field winding to which the field power controlled by the field current control circuit is applied. The field current control circuit has an input voltage higher than the voltage of the armature winding, and the field current control circuit changes the magnitude of the field current to control the rotation speed, thereby reducing the amount of power consumption. However, it is an electric motor that can take out electric power efficiently.

Before starting the detailed description of this example, first,
The speed characteristic of the separately excited motor will be described. When the armature winding resistance is R _a , the armature current is I _a , the magnetic flux of the magnetic pole is Φ, and the applied voltage of the motor is V, the rotation speed n and the torque T of the motor are k, a constant peculiar to the motor. Then, it is expressed by the following equations (1) and (2). n = (V−R _a I _a ) / k · Φ (1) T = k · Φ · I _a / 2 · π (2) FIG. 19 is based on the formula (1) and is based on the armature current I _a . The characteristic curve of the rotation speed n is shown.

According to the equation (1), when the armature winding resistance R _a is sufficiently small, the rotation speed n shows a constant value regardless of the armature current I _a . As can be seen from the equation (1), the magnetic flux Φ and the rotation speed n are inversely proportional to each other. In addition, since the effect of armature reaction is generally negligible, the magnetic flux Φ
Is proportional to the field current _If .

Next, FIG. 20 shows the relationship between the field current _If and the rotation speed n. 21 shows a graph of the torque T when I _f is constant. At this time, the torque T is I _a
It turns out that it is proportional to. However, when I _a increases,
Since the magnetic flux Φ decreases due to the armature reaction, the torque T
Indicates a slightly lowering behavior. From this, for example,
When the separately excited motor is used for speed control, the field current may be controlled.

According to the equation (1), it is understood that if the direction of the field current is reversed, the polarity of the magnetic flux Φ is reversed and the rotation direction can be reversed. Further, the ratio of the power required to generate the field by passing the field current and the power required to generate the torque by passing the current to the armature can be arbitrarily determined by design. it can.

[0035] Therefore, according to equation (1), under conditions of reduced flux [Phi, to obtain the speed and torque of the same degree, it can be seen that it is sufficient increase armature current I _a.

However, the armature mainly converts electric power into mechanical force, and the field magnet creates a magnetic flux serving as a medium for converting electric power into mechanical force. However, the armature may also generate a magnetic flux, and a mechanical force may be generated by the interaction of the magnetic flux with the field, and the magnetic flux generated by the field may be converted into a mechanical force.

In the present invention, paying attention to the general characteristics of the above-mentioned known separately excited motor, the ratio of the field power to the maximum power of the armature is set to a value smaller than 1/10 which is a conventional general range. As 1/100 or more and 1/10 or less, and by setting the input voltage of the field control circuit higher than the voltage of the armature winding, stable control without loss is possible even with a low armature winding voltage. In addition, it is possible to efficiently extract a large current from the battery.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description of each specific example, in the case of not only a fuel cell but a general battery,
When simply described as “battery” and limited to a fuel cell, it is described as “fuel cell” to distinguish from a general battery.

An electric motor shown as a first specific example of the present invention comprises a power source of the electric motor, a motor section for converting electric power of the power source into mechanical force, and a control section for controlling the motor section. There is. A specific configuration is shown in FIG.

The electric motor 1 uses a battery 11 as a power source. The battery 11 is a general battery and has a battery voltage of 4 V or less. For example, about 1 cell is suitable for a lithium-ion battery, and 1 to 3 cells are suitable for a nickel-cadmium battery, a nickel-hydrogen battery, a lithium-ion battery, and a lead storage battery.

The motor section includes a rotor 12 around which a field winding 14 is wound, an armature winding 13, and brush sections 15a, 15
It has b and the commutator 16. That is, this motor section is a brush type motor, and is provided with an electromagnet type field. Further, a field current control circuit 17 for controlling a field current of the field winding 14 as a control section for controlling the motor section, and a field power source as a current power source for the field winding 14 constituting the electromagnet. And a power supply 18.

In the first specific example, the armature winding 13 is provided on the fixed side and the field winding 14 is provided on the rotating side. Field winding 1
Electric power is supplied to 4 through the brush portions 15a and 15b and the commutator 16. In this specific example, the electric power supplied to the field winding 14 is 1/1 of the electric power supplied to the armature winding 13.
It is designed in advance to be 0 or less. In this specific example, as the armature winding 13, a thick wire having a low resistance that allows a sufficient current to flow even at a low voltage is used.

Further, the electric motor 1 is provided with a mechanical switch 19 between the battery 11 and the armature winding 13.
This mechanical switch 19 is for stopping the rotational force of the electric motor, and unlike a semiconductor element, does not generate a forward voltage. Especially, if a large mechanical switch is used,
By applying this mechanical switch 19, the resistance value can be made sufficiently smaller than the conductor resistance.

The power supply line from the battery 11 is connected to the armature winding 13 via the mechanical switch 19.
In the electric motor 1, as described above, without using an electronic circuit,
By supplying the electric power of the battery 11 directly to the armature winding 13 via the mechanical switch 19, the energy loss in this circuit portion is mainly only a minute loss due to the resistance of the lead wire. is there. Further, in order to reduce the resistance of the conductor wire, the battery 11 and the armature winding 13 are made as close to each other as possible, and the conductor wire is made as thick and short as possible. Further, in the above-described electric motor 1, if the volume of the armature winding 13 and the core is made significantly larger than the volume of the field winding 14 and the core, this power ratio can be set arbitrarily.

As described above, in this example, the wiring for preventing the voltage drop and the mechanical switch having a small resistance value are used, so that the loss in this path is almost eliminated.

When controlling the torque amount of the electric motor 1, the field current control circuit 17 adjusts the field current to control the rotation speed of the DC motor. According to equation (1),
The amount of torque is the square of the rotation speed n, that is, the armature current I _a
It will be proportional to the square of.

The voltage applied to the field current control circuit 17 is set to be sufficiently higher than the forward voltage of the switch element provided. For example, the voltage may be 10 times or more the forward voltage of the switch element. As a result, the energy loss in the field current control circuit 17 becomes 10% or less of the field power applied to the field winding 14, and the power in the field winding is, for example, the voltage of the field power supply 18. When set to 8V, 1/10 of the power of the armature winding 13
It is about 1/5, and is about ⅕ even at 4V. Therefore, the loss in the switching element of the field current control circuit 17 is 1% to 2% of the total power, which is a negligible loss.

Since the electric power in the field winding 14 is designed to be sufficiently smaller than the electric power in the armature winding 13, the electric power supplied from the field power supply 18 is smaller than the electric power supplied to the battery 11. It is small enough.

FIG. 2 shows a field current control circuit 17 in the electric motor 1 and a field power supply 18 connected to the field current control circuit 17. As the field current control circuit 17, a down type switching regulator can be used. The field current control circuit 17 includes a switch element 21,
22, 23, 24, an inductance 25, and a capacitor 26, and have a higher voltage than the battery 11 and
It is connected to the field power source 18 having a smaller power capacity. Here, a field power source of 4 V or more, which is larger than the battery 11, is used. The field current control circuit 17 includes a brush unit 15
Power is supplied to the field winding 14 via a and 15b and the commutator 16, and the current of the field winding 14 is controlled to change the magnetic flux direction of the field according to the rotation angle.

The switch element 24 is turned on when the A terminal connected to the brush portion 15a has a positive polarity, and the switch elements 21 and 23 are off. The potential at the point A is determined according to the ON duty of the switch element 22. That is, when the switching element 22 is on for a long time, the voltage at the point A rises in the positive direction.

The switch element 21 has a brush portion 15
It is turned on when the A terminal connected to a has a negative polarity. At this time, the switch elements 22 and 24 are
Off. The potential at the point A is determined according to the ON duty of the switch element 23. That is, the switch element 23
When the ON time of is long, the voltage at the point A rises in the negative direction.

Therefore, the field current control circuit 17 is
And use such a switching regulator
This enables control without power loss. Field current control
The control is performed by the control circuit 17 as follows. An example
For example, increase the torque of the electric motor 1 and increase the rotation speed.
If so, reduce the field current. At this time, the armature current I
_aWill increase. In addition, switching the rotation direction
This is easily possible by flowing the flow in the opposite direction. Also,
By controlling the field current, control the rotation speed,
It is possible to control the speed of a moving device equipped with this electric motor.
It As described above, the mechanical switch 19 causes the armature to move.
Current I_aBy completely shutting off the
In addition, the motor or the moving device equipped with this motor is mechanical
If you use the brake together, you can stop more safely.

Next, an electric motor 2 shown as a second specific example of the present invention will be described with reference to FIG.

The electric motor shown as the second specific example is characterized in that a fuel cell is used as a drive power source for the electric motor shown in FIG. However, in the following description, configurations having the same functions as those in FIG. 1 will be assigned the same reference numerals and detailed description thereof will be omitted.

The electric motor 2 comprises a power source, a motor section for converting the electric power of the power source into mechanical force, and a control section for controlling the motor section. Specifically, the fuel cell 31 is used as a power source. As the fuel cell 31, the well-known fuel cell shown in FIGS. 14 and 15 can be applied. The fuel cell 31 is supplied with oxygen gas from a valve 32 and hydrogen gas from a valve 33.

The motor section includes a rotor 12 around which a field winding 14 is wound, an armature winding 13, and brush sections 15a, 15
It has b and the commutator 16. That is, this motor section is a brush type motor, and is provided with an electromagnet type field. Further, a field current control circuit 17 for controlling a field current of the field winding 14 as a control section for controlling the motor section, and a field power source as a current power source for the field winding 14 constituting the electromagnet. And a power supply 18.

In the electric motor 2 using the fuel cell 31 as a power source, the amount of electric power applied is a product of voltage and current,
When configuring a fuel cell with one cell, it is sufficient to increase the cell area in order to increase the current. The area is practically about 500 mA / cm ² . By increasing the cell area in order to extract a large current, the number of cells or stacks in series can be reduced, and the fuel cell itself can be made thin. For example, the thickness per cell is 3 mm
Since it is about 6 mm, the total thickness is 3 to 30 mm in the case of a fuel cell composed of 1 to 5 cells.
It will be about.

Specifically, considering the case of the electric wheelchair, the electric power required for the electric wheelchair is about 100 W, and therefore the voltage is 0.7 in the case of the one-cell fuel cell.
Given V, the required cell area is 286 cm ² . Therefore, with such a thickness and area, the fuel cell can be mounted on a part of the flat member of the wheelchair, and the driving portion of the electric wheelchair can be downsized and simplified.

In the second embodiment using the fuel cell, the mechanical switch 19 is not necessary because the interruption of the electric power can be adjusted by supplying the hydrogen gas. Similarly, when a fuel cell is used, the armature winding is directly connected to the fuel cell or the like by a thick and short conductor having low resistance in order to prevent a voltage drop in the conductor.

Further, in the above-described first specific example, since the armature winding and the battery are directly connected, the rotation speed is not controlled during this period, but the second specific example using the fuel cell as the power source is used. In the example, the amount of power generation is controlled by reducing the overall power generation capacity and increasing the ratio of the heat loss of the battery to the output power, that is, adjusting the amount of hydrogen gas or oxygen gas to an amount that is less than or equal to the reactable capacity. The rotation speed can be controlled by.

Since the electric field power is selected to be sufficiently smaller than the electric power of the armature in both the electric motor 1 and the electric motor 2, the electric power supplied by the field power supply 18 is sufficiently smaller than the electric power supplied by the battery 11. . As the load increases, the back electromotive force decreases and the armature current I _a increases, so the battery
Supplying a current corresponding to the armature current I _a. When a fuel cell is used as a power source as in this example, the chemical reaction also proceeds according to the armature current I _a . Further, the consumption amount of hydrogen and oxygen increases according to the torque amount.

Since the field requires high voltage and low power consumption, the electric motor 1 and the electric motor 2 are, for example,
A fuel cell in which small cells are combined and stacked in about 10 stages may be used as the field power supply 18. Further, well-known batteries such as a nickel-cadmium battery, a nickel-hydrogen battery, a lithium-ion battery, and a lead storage battery can be stacked and used, or can be connected in series and used.

In both the first and second specific examples, the fuel valve is closed or the mechanical switch 1 is used.
By completely switching off the armature current I _a by switching 9, the rotation can be surely stopped. Further, by using a mechanical brake in addition to the fuel valve or the mechanical switch, the rotation can be stopped surely and safely.

Subsequently, the electric motor 3 shown as a third concrete example.
Is shown in FIG. The electric motor 3 shown as the third specific example is characterized in that in addition to the configuration of the electric motor 1 shown in FIG. 1, a power generation additional winding 34 for obtaining a regenerative current is provided. That is, the electric motor 3 can regenerate electric energy in the power generation additional winding 34 when braking the rotational force, and charge the field power supply 18 with the regenerative current obtained at this time.

The electric motor 3 has the same basic structure as the electric motor 1 and the electric motor 2 described above, such as a power source, a motor section for converting the electric power of the power source into a mechanical force, and a control section for controlling the motor section. Therefore, the configurations having the same functions as those in FIG. 1 are denoted by the same reference numerals and detailed description thereof will be omitted.

The power generation additional winding 34 is provided in the armature core provided with the armature winding 13 so as to intersect with the field magnetic flux created by the armature winding 13. The field power supply 28 can be charged by the current obtained when braking the rotation.

Subsequently, an electric motor 4 shown as a fourth specific example.
Is shown in FIG. The electric motor 4 includes, in addition to the configuration of the electric motor 2 shown in FIG. 3, a power generation additional winding 34 for obtaining a regenerative current.
And an electrolysis section 41. That is, the electric motor 4 regenerates electric energy in braking the rotational force in the power generation additional winding 34, and uses the regenerative current obtained at this time to electrolyze water in the electrolyzing unit 41 to convert the regenerative energy into hydrogen. It can be recovered as gas.

The electric motor 4 has the same basic structure as the above-described electric motors 1 to 3 such as a power source, a motor section for converting the electric power of the power source into mechanical force, and a control section for controlling the motor section. Therefore, configurations having the same functions as those in FIGS. 1 and 3 are denoted by the same reference numerals and detailed description thereof will be omitted.

When the fuel cell 31 is used, if either the hydrogen gas valve 33, the oxygen gas valve 32, or both valves are closed, the motor 4 is completely stopped because the armature current I _a is cut off. To be done. Further, in this case, the reaction at the electrode of the fuel cell is prevented and the electrode is protected at the same time.

In the electric motor 4, when a current is passed through the field winding 14 while the motor portion continues to move even when the active substance to the fuel cell 31 is cut off during the regenerative operation, the motor 4 becomes a generator. Although it operates, the electrode of the fuel cell 31 and the armature are always connected, so that a voltage may be continuously applied to the electrode of the fuel cell 31, a chemical reaction may be promoted at the electrode, and the electrode may be damaged. If the field current is cut off after the fuel supply is cut off, no voltage will be induced in the armature.
Although the electrodes of the fuel cell 31 can be protected, there is a problem that regenerative braking cannot be performed at this time.

The power generation additional winding 34 is provided on the armature core provided with the armature winding 13 so as to intersect with the field magnetic flux generated by the armature winding 13, and thus Overcoming the shortcomings.

The field magnetic flux interlinking with the power generation additional winding 34 is
It changes with the rotation of the rotor. Therefore, by providing the power generation additional winding 34 in this way, it is possible to generate a voltage higher than the voltage in the armature. Further, if the voltage generated in the power generation additional winding 34 is clamped, the voltage applied to the armature winding 13 is maintained below the clamp voltage. As the clamp, as schematically shown in FIGS. 4 and 5, for example,
It is conceivable to continuously wind up one conductor from the armature winding 13 to form the power generation additional winding 34, and further connect a voltage clamp element between the wound terminals.

In the electric motor 3 shown as the third specific example, during the regenerative operation, the circuit connected to the power generation additional winding 34 puts a large load on the battery. Therefore, the mechanical switch 19 is turned off to turn off the battery 11. Need to be separated. On the other hand, when the fuel cell 31 is used like the electric motor 4, it is only necessary to prevent hydrogen gas or oxygen gas, or both hydrogen gas and oxygen gas from being supplied to the fuel cell. Therefore, it is necessary to provide the mechanical switch 19. Disappears.

Here, when a secondary battery is connected as a clamp element, the electromotive voltage of the secondary battery is clamped and the energy generated by rotational braking is regenerated as electrical energy.
Further, when the electrolysis unit 41 is connected, a predetermined voltage required for electrolysis, that is, a value of about 2 V obtained by adding the overvoltage and the ohmic loss voltage to the theoretical electrolysis voltage (1.19 V) is clamped, and the regenerative energy is hydrogen gas. Can be collected as.

Here, the number of turns of the armature winding 13 is N ₁ ,
When the number of turns of the generator additional winding 34 is N ₂ and the clamp voltage is E _c , the voltage E _b applied to the electrodes of the fuel cell is
Is represented by equation (3).

E _b = N ₁ / (N ₁ + N ₂ ) E _c (3) Therefore, by appropriately selecting N ₂ and E _c ,
E _b can be set to a minimum value. As a result, the fuel cell 31
Can protect the electrodes.

By the way, the density of hydrogen gas is 7% of that of air.
Therefore, if hydrogen is used as the refrigerant, windage loss of the rotor can be reduced. Moreover, since the thermal conductivity of hydrogen is 6.7 times that of air and the surface emission rate is 1.5 times, hydrogen is also excellent as a heat-radiating gas. It is known that if the electric motor of each of the specific examples described above is cooled by hydrogen gas, the size of the electric motor itself can be reduced by 50% or more as compared with the case of no cooling. However, hydrogen gas is extremely difficult to handle when the concentration in the air is in the range of 4% to 75% because of the risk of ignition and explosion. Therefore, conventionally, when hydrogen is used as a refrigerant for heat dissipation of a generator or an electric motor, the hydrogen concentration is maintained at about 100%, and even in the hydrogen filling step, once hydrogen is filled with carbon dioxide gas, A complicated procedure such as replacement was required. In particular, a DC type electric motor using a brush portion has a risk of ignition of hydrogen due to sparks from the brush portion, and therefore hydrogen cannot be used as a refrigerant in a small electric motor.

However, the cooling method using hydrogen gas as a refrigerant is highly practical in terms of downsizing the electric motor and reducing noise by making the electric motor a closed structure, and further uses a fuel cell as a power source. For example, it is also beneficial that hydrogen gas as a refrigerant can be effectively used as a fuel gas.

Therefore, as a fifth specific example of the present invention, an electric motor 5 using hydrogen gas as a refrigerant will be described in detail with reference to FIGS. 6 to 8.

The electric motor 5 has, as a basic structure, a power source,
It has a motor section for converting the electric power of the power source into mechanical force, and a control section for controlling the motor section, and the motor section is filled with hydrogen gas as a refrigerant. The electric motor 5 is characterized in that it has a non-contact type motor unit in order to realize high safety even if hydrogen gas is used as a refrigerant. FIG. 6 shows a configuration of a motor movable portion 51 described below, FIG. 7 shows a cross section cut out by a plane perpendicular to the rotating direction of the motor movable portion 51, and FIG. The cross section cut out by the surface parallel to the rotation direction is shown.

The motor section of the electric motor 5 includes a power transmission transformer movable section 55 that receives the power supplied to the field winding 53 together with the power transmission transformer fixed section 54, and the rectifier circuit 5.
6, a polarity switching unit 57, a rotor 52 around which the field winding 53 is wound, and a motor moving unit 51 having a speed detecting unit 60 that detects the rotational angular speed of the rotor 52. Are protected by the motor section protective casing 50.

FIG. 9 shows a specific example of the power transmission transformer composed of the power transmission transformer fixed portion 54 and the power transmission transformer movable portion 55. In the power transmission transformer, power transmission transformer fixing unit 54 is composed of a fixed part core 54 ₁ and the stationary part winding 54 _2. In addition, the power transmission transformer movable part 5
5 comprises a movable part core 55 ₁ and a movable part winding 55 ₂ . The power transmission transformer fixed portion 54 and the power transmission transformer movable portion 55 are opposed to each other with a predetermined gap distance d.

The power transmission transformer has a function of supplying the power for generating the field to the field winding 53 wound around the rotor 52, and the higher the frequency of the AC power for transmission, the higher the selection. The power transmission transformer can be miniaturized.

A part of the magnetic path in a small power transmission transformer which does not become a mechanical load is fixed to the power transmission transformer fixing portion 54.
And the power transmission transformer movable part 55, and the magnetic path of the power transmission transformer movable part 55 and the power transmission transformer fixed part 5 are provided.
By adopting a structure in which the magnetic path of 4 is always magnetically tightly coupled regardless of changes in their relative positional relationship, it becomes possible to receive electric power between the movable portion and the fixed portion via the magnetic flux. No brush, commutator, or slip ring is required.

Here, in the facing surface where the fixed portion 54 and the movable portion 55 of the power transmission transformer face each other as shown in FIG.
The magnetic path is an open magnetic path, but the performance as a power transmission transformer can be improved by making the open magnetic path surfaces face each other and narrowing the gap between both transformer cores. The air gap distance d is a range in which both transformer core surfaces do not contact, for example,
It is preferably about 1/100 to 1/10000 of the total magnetic path length.

Next, the operation of the electric motor 5 will be described. The power generated by the high frequency power converter 70 is
Is applied to the power transmission transformer fixing unit 54, it is taken out in the power transmission transformer movable part winding 55 ₁ of the power transmission transformer movable portion 55. This electric power is rectified by the rectifier circuit 56 and applied to the field winding 53 provided in the rotor 52. Depending on the rotation angle of the field winding 53, the field winding 53
When the direction of the current flowing through is switched, the force acting between the field winding 53 and the armature winding 58 can be made a unidirectional rotational force. Here, the speed detection unit 60 includes a rotation shaft 59.
Shutter 63, light receiving element 61, and light emitting element 6 connected to
2 and the light amount of the light from the light emitting element 62 is changed by the light receiving element 61, the rotation angle of the rotating shaft 59, that is, the rotor 52 can be detected.

During the regenerative operation, the rotor 52 is rotated by mechanical force. Therefore, in the armature winding 58, a pulsating flow electromotive force corresponding to the rotation speed of the rotor 52 is generated across the magnetic flux in the armature winding 58. If the current flowing in one direction continues to flow in the rotor winding 58 without using the speed detecting unit 60, an AC voltage is generated in the armature winding 58. Therefore, DC power can also be obtained by rectifying this AC electromotive force by the rectifier circuit 56.

FIG. 10 shows the configuration of the polarity switch 57. As the polarity switch 57, a so-called full bridge type switch circuit can be applied. The polarity switch 57 includes switch elements 81, 82, 83, 84 and a switch element control circuit 85 that controls each switch element based on a signal from the speed detection unit 60. This specific example is particularly characterized in that the switching timing of the polarity switch 57 is synchronized with the rotation cycle of the rotor 52. FIG. 11 shows a waveform of the polarity change by the control of the switch element in the polarity switch 57.

Next, the electric motor 6 according to the sixth embodiment of the present invention will be described in detail with reference to FIGS. 12 and 13. The electric motor 6 is formed by curving and winding the fuel cell 100 shown in FIG. 14 along the outer peripheral surface of the motor unit protective casing 50 of the electric motor 5 shown in FIGS. It is intended to improve the efficiency of. That is, the electric motor 6 uses the fuel cell 200 as a driving power source, and the fuel cell 200 includes the valve 202, the oxygen pipe 203, and the hydrogen pipe 204, and is bent to form the outer periphery of the motor unit protective casing 50. It is wrapped around the surface.

When one cell of the fuel cell 200 is used,
Although the structure of the electric motor 6 is the simplest, usually, a plurality of cells are stacked and used to obtain a desired voltage.
In this specific example, a large number of unit cells shown in FIG. 14 are laminated, and further curved to be used so as to be able to be wound around the outer peripheral surface of the motor unit protective casing 50.

FIG. 1 is a schematic diagram showing the appearance of the fuel cell 200.
2 shows. Fuel cell 200 in FIG. 12, and the battery cell ₂₀₁ 1 to 201 ₅ is laminated, it has a structure sandwiched by current collectors 206 and 207 corresponding to the current collector 106 and 107 in FIG. 15. Current collector 206, 207
The collector terminals 208a, 208b, 209a, 20
9b is provided. However, the actual fuel cell 200
Is covered with an external housing having a structure that allows oxygen and hydrogen gas to flow in.

As shown in FIG. 13, the valve 202 in the electric motor 6 is a valve for adjusting the amount of hydrogen gas, and can be manually operated by the user. Further, the valve 202 may be configured to be adjustable from a remote point by a lever, a wire, or the like. Further, it is also possible to adopt a structure in which opening / closing can be controlled by electrically driving the electromagnetic valve. Although the valve 202 is provided on the hydrogen side, it can be designed so that the oxygen gas can be adjusted.

The oxygen pipe 203 is used for the fuel cell 2
00 is a pipe for supplying oxygen gas, one end of the oxygen pipe 203 is connected to the air electrode of the fuel cell 200, and air is supplied to the entire surface of the electrolyte.

Although the hydrogen pipe 204 may be directly connected to the hydrogen electrode, the electric motor 6 shown as the sixth specific example is shown.
In this case, hydrogen gas as fuel is used as a cooling medium for cooling the electric motor 6. In the electric motor 6, in the hydrogen passage 211 and the hydrogen passage 212, the motor portion and the hydrogen passage of the fuel cell are connected. Therefore, the hydrogen gas introduced from the hydrogen flow passage 211 into the motor unit is circulated in the motor unit and introduced into the fuel cell 200 through the hydrogen flow passage 212 opened / closed by the valve 202. Therefore, the flow rate of hydrogen as a refrigerant can be adjusted by opening / closing the valve 202, and the fuel cell 20
The flow rate of hydrogen gas to 0 can be adjusted.

The collector plate is composed of collector plate terminals 208a, 208.
b, 209a, 209b connected to the conductors 213, 21
4, 215 and 216 connect the armature winding with the shortest distance.

In the electric motor 6, the armature winding of the motor section is
Since it has two poles, the fuel cell 2
No. 00 air electrode is connected to one end of one armature winding, and a lead wire 215 connects the hydrogen electrode to one end of the other armature winding. Here, the winding directions of the armature windings are set so that the generated magnetic fluxes have opposite polarities. That is, when one magnetic pole supplies the magnetic flux of the N pole to the field, the other magnetic pole supplies the magnetic flux of the S pole.

The conducting wire may be of a current collector integrated type in which a part of the current collector is extended, or may be of an armature winding integral type in which a part of the armature winding is extended. it can. The conductor and the armature winding are connected at the shortest distance by cutting out a part of the electric motor 6. As a notch for this connection,
You may also use the hydrogen flow path.

Next, the operation will be described. Valve 202
Is installed close to the hydrogen electrode, the valve 20
As soon as 2 is closed, the hydrogen gas in the hydrogen electrode is consumed by the progress of the reaction, power generation is stopped, and the motor is turned on.
You can adjust the off. By gradually closing the supply of hydrogen gas, the amount of power generation can be adjusted and simple speed control can be performed.

The hydrogen gas also plays a role as a cooling solvent by recirculating in the housing of the electric motor 6. Since the recirculation amount of hydrogen gas increases as the supplied power increases, the heat generated from the armature winding, which increases according to the supplied power, can be efficiently dissipated.

Therefore, according to the sixth specific example in which the electric motor and the power generation section are integrated, no space for arranging the fuel cell is required, so that space saving is realized and the collector plate of the fuel cell is realized. It is possible to minimize the energy loss in the conductor wire for connecting the armature winding with the armature winding. When such a structure is adopted, the fuel cell is connected to the armature winding 58.
Energy loss can be minimized because the number of leads to In addition, since hydrogen gas used as a refrigerant and hydrogen gas used as a fuel cell can be shared, there is an advantage that hydrogen gas can be effectively utilized.

The present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0102]

As described above in detail, according to the electric motor and the method of controlling the electric motor of the present invention, the electric power loss can be reduced and the electric power can be efficiently taken out even from the battery having the low generated voltage. You can As a result, the battery can be made smaller and thinner.

Further, according to the electric motor and the method of controlling the electric motor of the present invention, by providing the armature with the power generation winding, when braking the rotation of the rotor, the power generation winding regenerates from the field. Electric current is obtained. The regenerative current can also charge the secondary battery or the fuel cell.

Further, according to the electric motor and the method of controlling the electric motor of the present invention, the introduction of the non-contact motor eliminates the sparks in the contact system, so that hydrogen gas can be used as the refrigerant and the noise can be reduced. This is useful in terms of improving cooling efficiency.

Further, by using a fuel cell as a power source and spatially connecting the fuel cell and a part of the non-contact motor part, hydrogen can be used as both a refrigerant and a fuel. At this time, if the energy lost as water due to the regenerative current is regenerated, the fuel efficiency is improved. Further, at this time, space saving is achieved by winding the fuel cell along the outer peripheral surface of the housing.

[Brief description of drawings]

FIG. 1 is a configuration diagram illustrating an electric motor shown as a first specific example of the present invention.

FIG. 2 is a configuration diagram illustrating a field current control circuit in the electric motor shown in FIG.

FIG. 3 is a configuration diagram illustrating an electric motor shown as a second specific example of the present invention.

FIG. 4 is a configuration diagram illustrating an electric motor shown as a third specific example of the present invention.

FIG. 5 is a configuration diagram illustrating an electric motor shown as a fourth specific example of the present invention.

FIG. 6 is a configuration diagram illustrating an electric motor shown as a fifth specific example of the present invention.

FIG. 7 is a cross-sectional view of the motor movable portion of the electric motor shown in FIG. 6, taken along a plane perpendicular to the rotation direction.

8 is a cross-sectional view of the motor movable portion of the electric motor shown in FIG. 6, which is cut away in a plane parallel to the rotating direction.

9 is a cross-sectional view illustrating a power transmission transformer of the electric motor illustrated in FIG.

10 is a configuration diagram illustrating a polarity switcher of the electric motor shown in FIG.

11 is a diagram showing a waveform of a polarity change when a switch element is controlled using the polarity switching device of the electric motor shown in FIG.

FIG. 12 is an external view illustrating a fuel cell used in an electric motor shown as a sixth example of the present invention.

FIG. 13 is a cross-sectional view of a motor movable portion of an electric motor according to a sixth specific example of the present invention, taken along a plane perpendicular to the rotation direction.

FIG. 14 is a perspective view showing a configuration of a general fuel cell.

15 is a diagram illustrating a stack structure in which a plurality of fuel cells shown in FIG. 14 are stacked.

FIG. 16 is a circuit diagram illustrating a voltage conversion circuit used in an electric motor including a general fuel cell.

FIG. 17 is a circuit diagram illustrating a frequency conversion circuit used in an electric motor including a general fuel cell.

FIG. 18 is a diagram illustrating the principle of a separately excited motor using a separately excited system.

FIG. 19 is a diagram showing a characteristic curve of the rotation speed n with respect to the armature current I _a .

FIG. 20 is a diagram showing a relationship between a field current _If and a rotation speed n.

FIG. 21 is a diagram showing the behavior of the torque T when I _f is constant.

[Explanation of symbols]

1, 2, 3, 4, 5 electric motor, 11 battery, 12 rotor, 13 armature winding, 14 field winding, 15a, 15
b brush part, 16 commutator, 17 field current control circuit, 18 field power supply, 19 mechanical switch 21,
22, 23, 24 switch element, 25 inductance, 26 capacitor, 31 fuel cell, 32 oxygen gas valve, 33 hydrogen gas valve, 34 power generation additional winding, 41 electrolysis section, 50 motor section protective casing, 51
Motor moving part, 52 rotor, 53 field winding, 54
Power transmission transformer fixed part, 55 Power transmission transformer movable part, 56 Rectifier circuit, 57 Polarity switching part, 58 Armature winding, 59 Rotating shaft, 60 Speed detecting part, 61 Light receiving element, 62 Light emitting element, 63 Shutter, 70 High frequency power converter, 200 fuel cell, 201 battery cell, 20
2 valves, 203 oxygen pipe, 204 hydrogen pipe, 206, 207 collector, 208a, 208b, 2
09a, 209b Current collector terminal, 211, 212 Hydrogen flow path, 213, 214, 215, 216 Conductor wire

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5H530 AA14 BB18 BB24 CC19 CD26                       CE02 CE16 DD23 DD28 EE05                       GG05                 5H571 AA02 BB02 CC02 DD01 EE02                       FF01 FF04 HA07 HB04 HC02                       HD01 HD03 LL08                 5H609 BB06 BB19 PP02 QQ03 RR70

Claims (19)

[Claims] 1. An electric motor for converting electric power from a power source into mechanical force, the armature having an armature winding to which armature power of a predetermined voltage or less is applied, and a field to which field power is applied. A field magnet having a winding, a rotor provided with the field magnet, and a field current controller for controlling a field current flowing in the field winding. The input voltage input to the field current control means is set higher than the voltage of the armature winding,
By controlling the magnitude of the field current so that the ratio of the field power to the maximum value of the armature power is 1/100 to 1/10 of the armature power, the rotation speed of the rotor is controlled. An electric motor characterized by being controlled. 2. The armature has a power generation winding different from the armature winding, and in the power generation winding, regenerative current is obtained from a field when braking rotation of the rotor. The electric motor according to claim 1, wherein: 3. The field power supply for obtaining the field power is provided, and the field power supply is a secondary battery and is charged by the regenerative current. Electric motor. 4. The electric motor according to claim 1, wherein the voltage of the power source is 4 V or less. 5. The electric motor according to claim 1, wherein the power source is a fuel cell. 6. The fuel cell is a hydrogen battery, is equipped with an electrolyzing means for electrolyzing water discharged from the hydrogen battery, and water is decomposed in the electrolyzing means by the regenerative current. The electric motor according to claim 5. 7. An electric motor for converting electric power from a power supply into mechanical force, the armature having an armature winding to which armature power of a predetermined voltage or less is applied, and a field to which field power is applied. A field having a winding, a rotor provided with the field, field current control means for controlling a field current flowing in the field winding, the armature, the field and the rotor. And a casing that isolates and protects the electric field from the outside, and a field from the fixed side power transmission transformer fixed to the casing to the field winding via the turning side turning side power transmission transformer fixed to the rotor. A non-contact motor unit that is rotated by transmitting a magnetic current is configured, and the field current control means sets the input voltage input to the field current control means to be higher than the voltage of the armature winding. ,
By controlling the magnitude of the field current so that the ratio of the field power to the maximum value of the armature power is 1/100 to 1/10 of the armature power, the rotation speed of the rotor is changed. An electric motor that is controlled to fill hydrogen gas as a refrigerant into the housing. 8. The electric motor according to claim 7, wherein the voltage of the power source is 4 V or less. 9. The electric motor according to claim 7, wherein the power source is a fuel cell using hydrogen. 10. The electric motor according to claim 9, wherein the fuel cell and a part of the housing are spatially connected to each other. 11. The electric motor according to claim 10, wherein the fuel cell is wound along an outer peripheral surface of the housing. 12. An armature having an armature winding to which armature power of a predetermined voltage or less is applied, a field magnet having a field winding to which field power is applied, and the field magnet. In a method of controlling an electric motor, which comprises a rotor and a field current control means for controlling a field current flowing through the field winding, the electric power from a power source is converted into mechanical force. The input voltage is higher than the voltage of the armature winding, and the ratio of the field power to the maximum value of the armature power is 1/100 to 1/1 of the armature power.
A method of controlling an electric motor, comprising a field current control step of controlling the number of rotations of the rotor by controlling the magnitude of the field current so as to be zero. 13. The method of controlling an electric motor according to claim 12, further comprising a step of obtaining a regenerative current from a field when braking the rotation of the rotor. 14. A method for controlling an electric motor according to claim 13, wherein a field power source for obtaining the field power is charged by the regenerative current. 15. The method of controlling an electric motor according to claim 12, wherein the power source is a fuel cell. 16. The method of controlling an electric motor according to claim 15, wherein the fuel cell is a hydrogen cell and has an electrolysis step of electrolyzing water discharged from the hydrogen cell. 17. An armature having an armature winding to which armature power of a predetermined voltage or lower is applied, a field magnet having a field winding to which field power is applied, and the field magnet. The casing includes a rotor, a field current control unit that controls a field current flowing through the field winding, and a case that isolates and protects the armature, the field, and the rotor from the outside. A non-contact motor unit that is rotated by transmitting a field current to the field winding from a fixed-side power transmission transformer fixed to the body through a rotation-side rotation-side power transmission transformer fixed to the rotor. In the method of controlling an electric motor configured to convert electric power from a power source into mechanical force, the input voltage input to the field current control means is set higher than the voltage of the armature winding, and the field power and the electric machine are The ratio to the maximum value of the child power is 1/100 to 1/1 of the armature power
A field current control step of controlling the number of revolutions of the rotor by controlling the magnitude of the field current so as to be 0, and cooling for cooling the non-contact motor section with hydrogen gas filled in the housing. A method of controlling an electric motor, comprising: 18. The method of controlling an electric motor according to claim 17, wherein the power source is a fuel cell using hydrogen. 19. The fuel cell and a part of the housing are spatially electrically connected to each other, and hydrogen gas is circulated between the fuel cell and the non-contact motor section. 18. The method for controlling an electric motor according to item 18.