JP2003153565A - Power generation system using transmitted energy from laser optical system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system where power as energy required for controlling a laser optical system is generated within the optical system, without having to depend on an external supply by making effective use of laser energy leaking from the laser optical system, which conventionally has merely been a loss. SOLUTION: In the power generation system using energy leaking from the laser optical system, a translucent-type reflector is deliberately used, and solar cells are placed behind the reflector. Thus, the energy of laser light, passing through, is used to generate power. The amount of electricity generated is adjusted, by varying the permeability of the reflector to vary the amount of energy which reaches the solar cells. At this time, a photoelectric element, corresponding to the wavelength of the laser is selected and used. Thus, energy can be extracted at high conversion efficiency. Further, thermoelectric elements are caused to generate electricity, utilizing heat emitted from the laser optical system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power generator using transmitted energy from a laser transmission optical system for transmitting energy to a remote place by a laser, and particularly to a laser optical system used in an environment where power supply is difficult. The present invention relates to an optimal power generation system as a power source for control means in a system.

[0002]

2. Description of the Related Art Normally, electric means is used in a control system for controlling a laser optical system, and conventionally, electric power is generally supplied from the outside to operate the control system. is there. However, recently, this laser optical system has been used not only in facilities such as laboratories but also in a wide variety of places. For example, it is used in outer space and remote areas, and in such an environment, electric power is not always easily supplied.

Regarding the energy problem, from the viewpoint of global environment conservation, in the current situation where problems have been raised for conventional thermal power, hydraulic power, and nuclear power, natural energy was used for photovoltaic power generation to extract energy from sunlight. It is regarded as a promising technological means among power generation methods, and solar cells have already been widely used. When supplying power by solar power generation, the issue is to secure the installation location of power generators and power transmission equipment. Since the energy density of light sent from the sun is low, a large light receiving area is required to supply a large amount of energy. It is difficult to secure the space in the suburbs of a large power consumption area such as the city, and it can be secured only in a place away from the power consumption areas such as outer space, the desert, and the ocean. I don't get it. However, in order to transport electric power from such a remote place, it depends on the power grid, and the power supply through the grid causes a large loss,
In addition to being inefficient, the cost for installation and the cost for maintenance will increase. As a method that does not rely on a power transmission network, a method of making microwaves with the obtained electric power and transmitting energy using the microwaves has been proposed, but this method has a problem that the directivity of the microwaves is not good. However, when constructing a long-distance energy supply network, it is a system with a lot of loss and disadvantageous in terms of transmission efficiency.

Therefore, the group of the present inventor has proposed a transmission system using a laser having a good directivity for energy transmission,
We presented a space-scale laser energy supply network that includes technical means capable of directly converting sunlight into a laser without power, and applied for a patent separately (Japanese Patent Application No. 2001-33067).
No. 3) In this energy supply network system, as schematically shown in FIG. 3, energy from a plurality of solar energy acquisition stations installed in outer space or the like is first sent to a laser relay station in the form of a laser. Energy is transmitted and supplied from the laser relay station to the ground facilities, satellites, space stations, spacecraft, etc. that require more energy, and by laser. Since the laser used at this time is for energy supply,
Inevitably, it becomes a very powerful laser with high energy.
In addition, various devices are installed in relay facilities and other facilities in outer space, etc., and a power source for operating them is required. However, it is not always easy to supply electric power because it is in outer space.

Further, as a technical problem of the laser optical system itself, it is general that the laser optical system comprises a resonator and a plurality of reflecting mirrors are used for guiding laser light. With the current technology, it is impossible to create a mirror surface that reflects 100% of the laser light, so the laser light is partially transmitted at the reflection part in the laser optical system. This phenomenon of transmission is merely the dissipation of laser light, and this is nothing but energy loss when viewed from the laser optical system.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is not to rely on the external supply of the energy necessary for controlling the laser optical system, but to effectively use the laser energy leaked from the laser optical system, which has been a simple loss in the past. It is to provide a system for generating electric power inside the optical system by utilizing the system.

[0007]

In the power generation system using leakage energy from the laser optical system of the present invention, a reflecting mirror is positively made transmissive, a solar cell is arranged on the back side, and the energy of the transmitted laser light is set. The electric power is generated by changing the transmittance of the reflecting mirror and changing the amount of energy reaching the solar cell. By selecting a photoelectric element corresponding to the wavelength of the laser as the photoelectric element used at that time, energy can be extracted with high conversion efficiency. Further, the thermoelectric element is used to generate electricity by utilizing the amount of heat emitted from the laser optical system.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, in a facility that relays laser light as an energy transmission medium, in view of the fact that the facility is in a situation where power supply is not easy due to the positional conditions such as outer space, The idea was to generate the electric power required to operate the installed laser optical system and other equipment by effectively utilizing the energy emitted from the laser optical system. The energy emitted from the laser optical system includes heat emission due to heat generation in addition to the laser light itself leaked from the optical member such as the above-mentioned mirror. Therefore, the present invention presents two power generation methods using laser light and heat energy as power generation methods in such facilities.

First, the power generation using laser light
This basically adopts a power generation method using the same photoelectric element as the solar cell. However, since the laser is not a mixture of light with many wavelengths like sunlight, but is a monochromatic light with a fixed wavelength, it is possible to efficiently generate electricity in the point that a photoelectric element suitable for the wavelength can be selected. . The problem is how to use the laser light leaked from the optical member for power generation, but the transmitted light at the above-mentioned mirror part is not so large in a normal laser optical system,
It is not practical to generate power only by the leaked light.
Therefore, in the present invention, the leaked light is intentionally added with a part of the laser light and used for power generation.

An example of an embodiment of a power generation device using transmission energy from a laser transmission optical system according to the present invention will be described with reference to FIG. (A) of the figure is a side view of the photovoltaic cell arranged on the back surface of the reflecting mirror. In the figure, it is a reflecting mirror, and is a photovoltaic cell arranged on the back surface of the reflecting mirror.
Part (b) of the figure is an enlarged view of a part of the side surface of the mirror surface, showing that part of the incident light is transmitted and goes to the solar cell on the back surface. (C) of the figure is a view of the mirror surface, which is an ordinary reflecting mirror except that a part of it is transmitted. (d) is the back of the mirror, with a photovoltaic cell attached. This photovoltaic cell was used to generate power using the light transmitted from the mirror surface. Here, although it is a reflecting mirror that transmits a part of the light, the transmittance on the mirror surface is set in consideration of the electric power required at this facility and the quantitative balance of the laser light received at this facility. As a means for determining the transmittance, it is possible to use one in which fine transmitting holes are distributed on the mirror surface according to the ratio, or one in which two mirrors each having a transmitting hole are adjusted in the overlapping positional relationship.

An example of an embodiment of the power generator using the heat energy from the laser transmission optical system according to the present invention will be described with reference to FIG. The example shown in FIG. 2 utilizes the heat generated in the lens in the laser transmission optical system. Since the optical system handles a laser used as an energy transmission medium, the amount of heat generated from the optical system also becomes large. In this embodiment, the generated heat is used as power generation energy without being discarded as mere heat release. Since the heat generated by the lens is transmitted to the frame of the lens as shown in the figure, a thermoelectric element is placed in the frame of the lens, and the side in contact with the lens is the high temperature side, and the outside is the heat dissipation section. Is set to the low temperature side, the electromotive force caused by the temperature difference is used as the electric power. By positively cooling the low temperature side with a radiator, the temperature difference can be increased and efficient power generation can be performed. This example uses heat generated in the lens, but even with other optical members, a thermoelectric element is arranged in the heat transfer path of that member, and the side through which heat is transmitted is the high temperature side and The electromotive force caused by the temperature difference can be used as electric power in a substantially similar form in which the outer side is the low temperature side.

Considering that heat radiation from a laser transmission optical system is an inevitable phenomenon in a facility that relays laser light as an energy transmission medium, power generation using this heat generation is performed first. In addition, it is rational to design the photovoltaic power generation using a part of the laser light to make up for the shortage of the electric power required by the facility only by the thermal power generation. That is, by setting the transmittance on the mirror surface with the photoelectric surface arranged on the back surface in accordance with this deficiency, the effective use of the energy to be transmitted can be measured.

[0013]

Since the present invention is a system for generating power by using laser energy leaking from a laser transmission optical system for transmitting energy to a remote place by a laser, it is necessary for the facility to produce a simple loss as it is. It can be effectively used by converting it to the generated power. This will cover the power required by the facility, starting with power supply to itself such as controlling the laser transmission optical system, power supply to equipment that maintains the transmission optical system, and power supply outside the transmission optical system. It becomes possible. Since it can be installed anywhere within the reach of the laser, the present invention is particularly useful in facilities where it is difficult to supply electric power from the outside, such as relay facilities for constructing a laser transmission network. As a specific use method of energy, a solar cell is arranged on the back surface of a reflecting mirror of a laser transmission optical system, and a method of generating power using the laser energy transmitted through the reflecting mirror by the solar cell is adopted as a reflecting mirror. Since it has a compact mechanism in which a solar cell is placed on the back of the, it is suitable for use in outer space, where weight requirements are severe.

As a concrete method of using energy, a method of providing power by using a thermoelectric generator using a thermoelectromotive force element and using the heat generated by the members of the laser transmission optical system to generate electricity is as follows:
Since the heat generation phenomenon that inevitably occurs with the operation of the laser transmission optical system is positively utilized, it is excellent in effective use of energy. Moreover, the structure is such that the side through which heat is transmitted is the high temperature side in the heat transfer path of the heat generating member,
Since this is a compact mechanism in which the thermoelectric elements are simply arranged in such a manner that the outside, which is the heat dissipation part, is on the low temperature side, this method is also suitable for use in outer space, where weight requirements are severe.
Further, the present invention causes power generation utilizing heat emission from a laser transmission optical system in a facility that relays laser light as an energy transmission medium, and the thermal power generation is performed within the power required in the facility. It is a power generation system that sets the transmittance of a reflector with a photoelectric field on the back so that the amount that is insufficient by itself can be supplemented by photovoltaic power generation using a part of laser light. The effective use of energy can be realized in the network used as.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of an embodiment of a power generation device using transmission energy from a laser transmission optical system according to the present invention.

FIG. 2 is a diagram showing an example of an embodiment of a power generation device using heat energy from a laser transmission optical system according to the present invention.

FIG. 3 is a conceptual diagram showing a space-scale laser energy supply network to which the present invention is applied.

[Explanation of symbols]

1 Laser reflector 3 Lens 2 Photoelectric 4 Thermoelectric element

Continued front page    (72) Inventor Wood Plate Katsuto             1 Kanagaki, Kanazawa, Kakuda City, Miyagi Prefecture Aerospace             Kadoda Space Propulsion Technology Research Center             Within (72) Inventor Akio Moro             1 Kanagaki, Kanazawa, Kakuda City, Miyagi Prefecture Aerospace             Kadoda Space Propulsion Technology Research Center             Within (72) Inventor Kazuhisa Fujita             1-16-6 Izumichuo, Izumi Ward, Sendai City, Miyagi Prefecture (72) Inventor Masakatsu Nakano             4-1-8 Honcho, Kawaguchi City, Saitama Prefecture             Inside the business group F-term (reference) 5F051 BA02 BA18 JA20 KA06                 5F072 YY20

Claims (4)

[Claims] 1. A system for generating electric power by using laser energy leaking from a laser transmission optical system for transmitting energy to a remote place by a laser. 2. A power generation system in which a photovoltaic cell using a photoelectric element is arranged on the back surface of a reflecting mirror in a laser transmission optical system, and the photovoltaic cell uses the laser energy transmitted through the reflecting mirror to generate electricity. 3. A thermoelectric generator using a thermoelectromotive element in which the side through which heat is transmitted is the high temperature side and the outside serving as the heat radiating portion is the low temperature side in the heat conduction path of the heat generating member in the laser transmission optical system. The power generation system according to claim 1, wherein the power generation system is arranged and power is generated by using heat generated from a member of the laser transmission optical system. 4. In a facility that relays laser light as an energy transmission medium, power generation is performed by utilizing heat emission from a laser transmission optical system, and this thermal power generation is included in the power required in the facility. A power generation system that sets the transmittance of a reflecting mirror with a photoelectric surface on the back so that the photovoltaic power generation that uses a part of the laser light will make up for the shortage.