JP2011129433A - Induction heating device and power generation system equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an induction heating device and a power generating system using the same which is of a simple structure, but has good performance suitable for heating a heating medium and is practical enough. <P>SOLUTION: The induction heating device 101 includes: a rotor 11 fixed to a rotating shaft 21 and formed by a magnetic material of a noncircular outline; fixed magnetic poles 121-124 (a fixed magnetic pole group 12) arranged in opposition to the rotor on an outer periphery of the same and with alternate polarities; coil elements 131-134 (coils 13) arranged on the fixed magnetic poles and generating direct current magnetic fields; a heating part 14, arranged between the fixed magnetic poles and the rotor which is made of a conductive material; and a piping 15 arranged at the heating part, through which the heating medium circulates. And a magnetic field is formed by the fixed magnetic pole group 12 and the rotor 11 through DC current flow of the coils 13, and the heating part 14 is heated by induction by changes of magnetic flux passing through the heating part 14 by rotation of the rotor 11, and the heating medium inside of the piping 15 is heated. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an induction heating apparatus that heats a heat medium using induction heating and a power generation system including the induction heating apparatus.

  As a device for heating water, a heating device using induction heating (eddy current) has been proposed (for example, see Patent Document 1). In the eddy current heating device described in Patent Document 1, a rotatable rotor having a permanent magnet disposed on the outer periphery, and a conductive passage provided in a fixed manner on the outer periphery of the rotor and having a flow passage through which water flows. A heating part for the material. As the rotor rotates, the magnetic lines of force generated by the permanent magnets on the outer periphery of the rotor move through the heating unit, so that an eddy current is generated in the heating unit and the heating unit itself generates heat. As a result, the heat generated in the heating unit is transmitted to the water flowing through the internal flow passage, and the water is heated.

  The above-mentioned technology is mainly intended to supply hot water using energy such as wind power, but in recent years, power generation systems using renewable energy such as wind power, hydraulic power, and wave power are also attracting attention. .

  For example, Non-Patent Documents 1 to 3 describe technologies relating to wind power generation. In wind power generation, a windmill is rotated by wind and a generator is driven to generate electric power. Wind energy is converted into rotational energy and extracted as electric energy. A wind power generation system generally has a structure in which a nacelle is installed at the top of a tower, and a horizontal axis wind turbine (a wind turbine whose rotation axis is substantially parallel to the wind direction) is attached to the nacelle. The nacelle stores a speed increaser that speeds up and outputs the rotational speed of the rotating shaft of the windmill, and a generator that is driven by the output of the speed increaser. The speed increaser increases the number of rotations of the wind turbine to the number of rotations of the generator (for example, 1: 100), and a gear box is incorporated.

  Recently, there is a tendency to increase the size of wind turbines (wind power generation systems) in order to reduce power generation costs, and wind turbines with a diameter of 120 m or more and 5 MW have been put into practical use. Such large-scale wind power generation systems are huge and heavy, and are often constructed offshore for construction reasons.

  In wind power generation, the power generation output (power generation amount) fluctuates with the fluctuation of wind power. Therefore, a power storage system is added to the wind power generation system, unstable power is stored in the storage battery, and the output is smoothed. It has been broken.

JP 2005-174801 A

“Wind Power Generation (01-05-01-05)”, [online], Atomic Encyclopedia ATOMICA, [Searched on December 18, 2009], Internet <URL: http://www.rist.or.jp/ atomica /> “2000kW large wind power generation system SUBARU80 / 2.0 PROTOTYPE”, [online], Fuji Heavy Industries, Ltd. [searched on December 18, 2009], Internet <URL: http://www.subaru-windturbine.jp/home/ index.html> “Wind Course”, [online], Mitsubishi Heavy Industries, Ltd., [Searched on December 18, 2009], Internet <URL: http://www.mhi.co.jp/products/expand/wind_kouza.html>

  However, in the conventional induction heating apparatus as described in Patent Document 1 described above, since a permanent magnet is used as a means for generating a magnetic field (lines of magnetic force), the following problems may occur.

  Induction heating energy is known to be proportional to the square of the magnetic field strength (H). However, a permanent magnet generally has a weak magnetic field that can be generated, so that sufficient induction heating energy cannot be obtained. There is a possibility that a heat medium (for example, a liquid such as water) cannot be heated to a temperature.

  In addition, it is conceivable to use a neodymium magnet to obtain a strong magnetic field, but the neodymium magnet is weak against heat, and when the temperature rises, the magnetic properties deteriorate (this is the same as a general ferrite magnet). Therefore, in the conventional induction heating apparatus in which the permanent magnet is disposed near the heating unit, the temperature of the permanent magnet is likely to rise, and as a result, the heat medium may not be heated to a desired temperature. Furthermore, since permanent magnets deteriorate in magnetic characteristics over time, there is a possibility that they cannot be used for a long time. By the way, in order to prevent the deterioration of the magnetic properties due to heat, it is conceivable to provide a heat insulating material around the permanent magnet. However, since the heat insulating material is usually a non-magnetic material, it results in a decrease in the magnetic field. There is.

  On the other hand, in a generally well-known wind power generation system, a power storage system is installed for smoothing the output. However, since the power storage system requires components such as a converter to store power in the storage battery, This increases complexity and power loss. Further, in the case of a large-scale wind power generation system, a large-capacity storage battery corresponding to the amount of power generation is required, which increases the cost of the entire system.

  Moreover, many of the causes of failure of the wind power generation system are due to problems with the gearbox, more specifically, the gear box. When a gearbox breaks down, it is usually handled by replacing the gearbox. However, if a nacelle is installed at the top of the tower, it takes a lot of time and effort to attach and remove the gearbox. Therefore, recently, there is a gearless variable-speed wind generator that does not require a gear box.

  However, the gearless case can be dealt with by specifically increasing the number of poles of the generator (multipolar generator), but the generator becomes larger and heavier than when using a speed increaser. In particular, in a large-scale wind power generation system of 5 MW class, the weight of the generator is considered to exceed 300 tons (300000 kg), and it is difficult to arrange in the nacelle.

  The present invention has been made in view of the above circumstances, and one of its purposes is a simple configuration, but has good performance suitable for heating a heat medium and is sufficiently practical. Is to provide a simple induction heating apparatus. Another object is to provide a power generation system including the induction heating device.

  The induction heating device of the present invention includes a rotating body, at least a pair of fixed magnetic poles, a coil, a heating unit, and piping. The rotating body is made of a magnetic material that is fixed to the rotating shaft and has a non-circular outer shape. The fixed magnetic pole is disposed on the outer periphery of the rotating body so as to face the rotating body, and the polarity of each magnetic pole is different. The coil is provided on the fixed magnetic pole and generates a DC magnetic field. The heating unit is disposed between the fixed magnetic pole and the rotating body and is made of a conductive material. Piping is provided in a heating part and a heat carrier distribute | circulates. In this apparatus, a magnetic circuit passing through one fixed magnetic pole, the rotating body, and the other fixed magnetic pole is formed by direct current application of the coil. The rotation of the rotating body changes the magnetic flux passing through at least a part of the heating unit disposed between the fixed magnetic pole and the rotating body, so that the heating unit is induction-heated and heats the heating medium. Features.

  According to the induction heating apparatus of the present invention, since a coil (electromagnet) is used as the magnetic field generating means, a stronger magnetic field can be generated as compared with a conventional apparatus using a permanent magnet. Specifically, it is possible to generate a strong magnetic field by increasing the direct current that flows through the coil, and it is also possible to adjust the strength of the magnetic field by controlling the energizing current. In addition, in the case of a coil, compared to a permanent magnet, the magnetic characteristics are less likely to deteriorate due to a temperature rise, and the magnetic characteristics are less likely to deteriorate over time. Furthermore, when providing a heat insulating material to prevent the temperature of the coil from rising, it is not always necessary to arrange the heat insulating material in the middle of the magnetic circuit (specifically, between the fixed magnetic pole and the heating part). If it is provided only on the side of the coil facing the heating part, the magnetic field will not be lowered. Even when the heat insulating material is disposed in the middle of the magnetic circuit, a sufficient magnetic field strength can be maintained by increasing the energization current. That is, the function as the magnetic field generating means can be sufficiently exhibited. As a result, sufficient induction heating energy can be obtained, so that the heat medium can be heated to a predetermined temperature (for example, 100 ° C. to 600 ° C.). Therefore, the heat medium can be efficiently heated, and good performance suitable for heating the heat medium can be obtained.

  In the induction heating apparatus of the present invention, the rotating rotating body is made of a magnetic material, and the coil is mounted on the fixed magnetic pole fixed without rotating, so that the direct current power source connected to the coil can be easily routed. Examples of the magnetic material include iron, nickel, cobalt, silicon steel, permalloy, and ferrite. In addition, by providing a pipe in the heating section that is fixed without rotating, a rotary joint that allows the pipe to rotate in the connection between the pipe and the supply / discharge pipe that communicates with the pipe and supplies and discharges the heat medium from the outside There is no need to use a simple connection, and a robust connection can be realized. Specifically, when the heat medium is heated, the pressure in the pipe increases. For example, when the heat medium is water (steam), the pressure reaches about 25 MPa (250 atm) at 600 ° C. When the heating part (pipe) rotates, a special rotary joint that can withstand the pressure is required. When it does not rotate, there is no need for a rotary joint. For example, a simple connection such as welding the supply / discharge pipe and the pipe By adopting this method, a sufficiently robust structure can be realized.

  The mechanism by which the heat medium in the induction heating apparatus of the present invention is heated will be described. In the induction heating apparatus of the present invention, a magnetic circuit is formed by flowing a direct current through the coil to the fixed magnetic pole facing the rotating body and from one fixed magnetic pole through the rotating body to the other fixed magnetic pole. . When the non-circular rotating body rotates, a gap (distance) between the fixed magnetic pole and the rotating body changes in a part between the fixed magnetic pole and the rotating body. Specifically, when the fixed magnetic pole and the rotating body face each other, the distance between the fixed magnetic pole and the rotating body becomes narrow, and the fixed magnetic pole and the rotating body become continuous, the magnetic flux easily flows from the fixed magnetic pole to the rotating body. Become. On the other hand, when the distance between the fixed magnetic pole and the rotating body becomes large due to the rotation of the rotating body and the fixed magnetic pole and the rotating body become discontinuous, the magnetic flux hardly flows from the fixed magnetic pole to the rotating body. As a result, the magnetic flux (magnetic field) that passes through at least a part of the heating unit disposed between the fixed magnetic pole and the rotating body changes, whereby the heating unit is induction-heated and the heat medium is heated.

  In the induction heating apparatus of the present invention, the outer shape of the rotating body is non-circular, and if the distance between the fixed magnetic pole where the heating unit is disposed and the rotating body changes while the rotating body makes one rotation, There is no particular limitation. Examples of the outer shape of the rotating body include a rectangular shape, an elliptical shape, a polygonal shape, a cross shape, an arc shape (bow shape), and a gear shape. In addition, examples of the heat medium include water, oil, liquid metals (Na, Pb, etc.), liquids such as molten salts, and gases.

  As one form of the induction heating device of the present invention, during one rotation of the rotating body, one fixed magnetic pole and the rotating body, and the rotating body and the other fixed magnetic pole are substantially opposed to each other, and the rotating body rotates. However, it is mentioned that the total magnetic flux flowing through the magnetic circuit formed by the fixed magnetic pole and the rotating body is substantially constant.

  According to this configuration, the total magnetic flux flowing through the magnetic circuit formed by the fixed magnetic pole and the rotating body is substantially constant, that is, the magnetic flux flowing through the fixed magnetic pole does not change substantially. As a result, an induced electromotive force (back electromotive force) is not substantially generated in the coil disposed on the fixed magnetic pole, and power loss can be suppressed. Further, eddy currents are not substantially generated in the fixed magnetic pole, and eddy current loss can be reduced. Furthermore, generation of cogging torque can be suppressed, and smooth rotation of the rotating body can be realized.

  As one form of the induction heating apparatus of this invention, when a fixed magnetic pole and a rotary body oppose, it is mentioned that the area of a rotary body is small with respect to a fixed magnetic pole.

  According to this configuration, when the fixed magnetic pole and the rotating body face each other and the distance between the fixed magnetic pole and the rotating body is narrow, the rotating body is smaller than the fixed magnetic pole so that the rotating body can be moved from the fixed magnetic pole to the rotating body. Thus, the magnetic flux flowing through the heating portion concentrates and the magnetic flux (magnetic field) passing through the heating unit can be increased. As a result, it is possible to greatly change the magnetic field in the heating unit and improve the heating efficiency.

  One form of the induction heating device of the present invention is that the coil is a superconducting coil.

  Examples of the coil used in the induction heating device of the present invention include a normal conducting coil such as a copper wire and a superconducting coil. In the induction heating apparatus of the present invention, since the coil is connected to a DC power source and generates a DC magnetic field, if it is a superconducting coil, the electrical resistance is zero, and no heat is generated in the coil even when a large current is passed. Therefore, compared to a normal conducting coil, heat generation of the coil due to flowing a large current can be suppressed, and a stronger magnetic field can be generated.

  As one form of the induction heating apparatus of this invention, a rotating shaft is connected to a windmill and using wind power for the motive power which rotates a rotary body is mentioned.

In the induction heating apparatus of the present invention, as the power of the rotating body (rotating shaft), an internal combustion engine such as an electric motor or an engine can be used, and renewable energy such as wind power, hydraulic power, and wave power can be used. . If renewable energy is used, an increase in CO ₂ can be suppressed, and it is particularly preferable to use wind power.

  The power generation system of the present invention includes the above-described induction heating device of the present invention and a power generation unit that converts heat of the heat medium into electric energy.

  The power generation system of the present invention is a novel power generation system that does not use the heat of the heat medium heated by using the above-described induction heating device for power generation. For example, if a windmill is connected to the rotating shaft of the induction heating device and wind power is used as the power of the rotating body, the wind energy can be converted from rotational energy to thermal energy and extracted as electrical energy. And according to the electric power generation system of this invention, it was set as the structure which converts heat into an electrical energy, By storing energy as heat using a thermal accumulator, efficient and stable electric power generation is realizable. In addition, a heat storage system that can store heat in a heat accumulator and extract heat necessary for power generation is simpler than a power storage system, and the heat accumulator is less expensive than a storage battery. Furthermore, it is not necessary to provide a speed increaser as in the conventional wind power generation system, and it is possible to avoid a gearbox trouble.

  The induction heating device of the present invention includes a rotating body made of a non-circular magnetic material, at least a pair of fixed magnetic poles facing the rotating body, and a coil provided on the fixed magnetic poles, but has a simple configuration. It has good performance suitable for heating the heat medium. Further, the power generation system of the present invention is a novel power generation system that does not use the heat of the heat medium heated by using the above-described induction heating device for power generation.

It is the schematic which shows the structure of the induction heating apparatus which concerns on Embodiment 1, (A) shows the state where the fixed magnetic pole and the protrusion of a rotary body oppose, and the distance between a fixed magnetic pole and a rotary body is narrow , (B) shows a state in which the rotating body rotates from the state of (A) and the distance between the fixed magnetic pole and the rotating body is wide. It is a figure which shows typically the time change of the magnetic field in the C point of FIG. It is the schematic which shows the structure of the induction heating apparatus which concerns on Embodiment 2, (A) shows one state in which a rotary body is rotating, (B) shows another state in which a rotary body is rotating. . It is the schematic which shows the structure of the induction heating layer apparatus which concerns on Embodiment 3, (A) shows one state in which a rotary body is rotating, (B) shows another state in which a rotary body is rotating. Show. It is the schematic which shows the structure of the induction heating layer apparatus which concerns on Embodiment 4, (A) shows one state in which a rotary body is rotating, (B) shows another state in which a rotary body is rotating. (C) shows still another state in which the rotating body is rotating. FIG. 9 is a schematic diagram showing a configuration of an induction heating device according to a fifth embodiment. It is the schematic which shows an example of the whole structure of the electric power generation system which concerns on this invention.

  Embodiments of the present invention will be described with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts.

<Induction heating device>
(Embodiment 1)
An induction heating apparatus 101 according to Embodiment 1 shown in FIG. 1 includes a rotating body 11, a fixed magnetic pole group 12, a coil 13, a heating unit 14, and a pipe 15. Hereinafter, the configuration of the induction heating apparatus 101 will be described in detail.

  The rotating body 11 is fixed to a rotating shaft 21 that is rotatably supported, and an outer shape viewed from the axial direction is formed in a substantially cross shape having four protrusions 111 to 114. The rotating body 11 is made of a magnetic material. In this example, the rotating body 11 is formed of a laminated steel plate in which silicon steel plates are laminated in the rotation axis direction. In addition, a dust core obtained by applying an insulating coating to the surface of a magnetic powder such as iron powder and press-molding the powder may be used. Here, it is assumed that the rotating body 11 rotates counterclockwise (the same applies to FIGS. 3 to 6).

  The fixed magnetic pole group 12 is arranged with a predetermined space between the rotating body 11 so as to cover the outer periphery of the rotating body 11, and a cylindrical yoke portion 120, and a centripetal shape from the yoke portion 120. It consists of four fixed magnetic poles 121 to 124 extending. The fixed magnetic poles 121 to 124 are arranged at cross positions as viewed from the rotation axis direction. In this example, the width of the fixed magnetic poles 121 to 124 is substantially the same as the width of the protrusions 111 to 114 of the rotating body 11. And the opposed areas of the fixed magnetic pole and the protrusion of the rotating body when the fixed magnetic pole and the protrusion of the rotating body face each other are substantially equal. The fixed magnetic pole group 12 is made of a magnetic material, and in this example, is formed of a laminated steel plate in which silicon steel plates are laminated in the axial direction. The fixed magnetic pole group 12 is fixed so as not to rotate.

  The fixed magnetic pole group 12 is provided with a coil 13 for generating a DC magnetic field, and coil elements 131 to 134 are attached to the fixed magnetic poles 121 to 124, respectively. In addition, a DC power source (not shown) is connected to each of the coil elements 131 to 134. In this example, the direction of the direct current supplied to each coil element 131 to 134 is controlled to determine the direction of the magnetic flux flowing through each fixed magnetic pole 121 to 124, and the polarity of each fixed magnetic pole 121 to 124 is N pole. And S poles are alternately magnetized. Specifically, the direction of the magnetic flux flowing through each of the fixed magnetic poles 121 to 124 flows from the yoke part 120 side to the rotating body 11 side in the fixed magnetic poles 121 and 123, and in the fixed magnetic poles 122 and 124, the rotating body 11 side. Flows from the side toward the yoke 120 side. Each coil element is a superconducting coil, and the surroundings are covered with a cooling jacket (not shown) and cooled to maintain the superconducting state.

  The heating unit 14 is disposed between the fixed magnetic pole group 12 and the rotating body 11 and is formed in a cylindrical shape so as to cover the periphery of the rotating body 11. The heating unit 14 is made of a conductive material, and is formed of a metal such as aluminum, copper, or iron, for example. The heating unit 14 is fixed so as not to rotate.

  The heating unit 14 is provided with a pipe 15 through which a heat medium flows. In this example, a plurality of flow passages extending in the axial direction are formed inside the heating unit 14, and these are used for the pipe 15 through which the heat medium flows. The heating unit 14 and the pipe 15 are thermally connected. In this example, the pipes 15 are intensively provided at positions corresponding to the fixed magnetic poles 121 to 124 in the circumferential direction of the heating unit 14.

  Further, a heat insulating material 16 may be disposed around the heating unit 14. In this example, the heat insulating material 16 is provided at locations on the inner and outer peripheral surfaces of the heating unit 14 and the end surface of the heating unit 14 excluding the location where the pipe 15 is disposed. As the heat insulating material 16, for example, rock wool, glass wool, foamed plastic, brick, ceramics or the like can be used.

  Next, the mechanism by which the heat medium in the induction heating device 101 is heated will be described in detail.

  In the induction heating device 101, by applying direct current to the coil elements 131 to 134, magnetic flux flows to the fixed magnetic poles 121 to 124, and from the one fixed magnetic pole 121 and 123 through the rotating body 11, the other fixed magnetic pole 122 and A magnetic circuit leading to 124 is formed. Further, the magnetic flux flowing through the other fixed magnetic poles 122 and 124 passes through the yoke portion 120 and reaches the one fixed magnetic pole 121 and 123. That is, a closed magnetic circuit is formed by the fixed magnetic pole group 12 and the rotating body 11 (dotted line arrows in FIG. 1 show an image of the flow of magnetic flux, and the same applies to FIGS. 3 to 6). Here, the state of FIG. 1A, that is, the fixed magnetic poles 121 to 124 and the protrusions 111 to 114 of the rotating body 11 face each other, and the distance between the fixed magnetic pole and the rotating body becomes narrow, and the fixed magnetic poles 121 to 124 become smaller. When the rotating body 11 and the rotating body 11 are in a continuous state, the magnetic resistance decreases, and the magnetic flux easily flows from the fixed magnetic poles 121 and 123 to the rotating body 11 or from the rotating body 11 to the fixed magnetic poles 122 and 124. On the other hand, when the rotating body 11 rotates and the state shown in FIG. 1B, that is, when the distance between the fixed magnetic pole and the rotating body becomes large and the fixed magnetic poles 121 to 124 and the rotating body 11 become discontinuous, And the magnetic flux hardly flows from the fixed magnetic poles 121 and 123 to the rotating body 11 or from the rotating body 11 to the fixed magnetic poles 122 and 124. As a result, the rotation of the rotating body 11 changes the magnetic flux that passes through the positions corresponding to the fixed magnetic poles 121 to 124 of the heating unit 14, and the strength of the magnetic field in this part periodically changes, so that the heating unit 14 is induction-heated, and the heat medium in the pipe 15 is heated.

  FIG. 2 is a diagram schematically showing the temporal change of the magnetic field at point C in FIG. In the state of FIG. 1 (A), the magnetic field at point C becomes strong, and becomes maximum and maximum when the distance between the fixed magnetic pole and the rotating body becomes the narrowest. On the other hand, in the state of FIG. 1B, the magnetic field at the point C becomes weak, and becomes minimum and minimum when the distance between the fixed magnetic pole and the rotating body becomes the widest.

  Further, in the induction heating apparatus 101, the width of the protrusions 111 to 114 of the rotating body 11 is reduced with respect to the fixed magnetic poles 121 to 124, and the rotating body with respect to the fixed magnetic pole when the fixed magnetic pole and the protrusion of the rotating body face each other. The opposing area of the protrusions may be reduced. As a result, the magnetic flux flowing from the fixed magnetic pole to the rotating body is concentrated, and the magnetic flux passing through the heating unit 14 corresponding to the portion where the distance between the fixed magnetic pole and the rotating body is reduced increases. As a result, the amplitude of the magnetic field applied to the heating unit 14 is increased, and the heating efficiency can be improved. For example, the opposing area of the protrusion of the rotating body with respect to the fixed magnetic pole can be reduced to half or less.

  In addition, in the induction heating apparatus 101, the case where the coil elements 131 to 134 are mounted on the fixed magnetic poles 121 to 124 has been described as an example. However, the coil is, for example, one of the fixed magnetic poles 121 and 123 or the other fixed magnetic pole. You may provide only in either 122 and 124. Even when a coil element is attached only to one of the fixed magnetic poles 121 and 123, a magnetic circuit similar to that shown in FIG. 1 is formed.

  In the induction heating apparatus of the first embodiment described above, the fixed magnetic poles 121 to 124 do not face the protrusions of the rotating body 11 while the rotating body 11 rotates once (see FIG. 1B). Therefore, since the magnetic resistance of the entire magnetic circuit formed by the fixed magnetic pole group 12 and the rotating body 11 changes, the total magnetic flux flowing through the magnetic circuit also changes. As a result, an induced electromotive force (back electromotive force) is generated in the coil elements 131 to 134 disposed in the fixed magnetic poles 121 to 124, and power loss is generated, and eddy currents are generated in the fixed magnetic poles 121 to 124 and the yoke portion 120. There is a concern that the efficiency will decrease, such as eddy current loss due to the occurrence of eddy current. Here, for example, by reducing the thickness (for example, 0.1 mm or less) of the silicon steel plate per laminated steel plate forming the rotating body 11 and the fixed magnetic pole group 12, eddy current loss can be reduced, but it becomes expensive. . Furthermore, cogging torque is generated due to a change in magnetic flux, and the rotating body 11 may not rotate smoothly.

(Embodiment 2)
In the second embodiment, a configuration capable of solving the above-described problem that cannot be solved by the first embodiment will be described. In addition, in the following description, the point which is the same as the induction heating apparatus of Embodiment 1 shown in FIG. 1 is abbreviate | omitted description, and it demonstrates centering around difference.

  In the induction heating device 102 according to the second embodiment shown in FIG. 3, the opposed surfaces of the fixed magnetic poles 121 to 124 facing the protrusions 111 to 114 of the rotating body 11 substantially form a cylindrical surface centered on the rotating shaft 21. is doing. Specifically, the distance between the adjacent fixed magnetic poles on the facing surface side is narrower than the width of the protrusion of the rotating body, for example, less than half the width of the protrusion of the rotating body.

  In the induction heating device 102 of FIG. 3, during one rotation of the rotating body 11, one fixed magnetic pole 121 and 123 and the protrusion of the rotating body 11, and the protrusion of the rotating body 11 and the other fixed magnetic pole 122 and 124 They will always face each other. Therefore, even if the rotating body 11 rotates, the total magnetic flux flowing through the magnetic circuit formed by the fixed magnetic pole group 12 and the rotating body 11 is substantially constant. That is, since the fixed magnetic pole and the rotating body are substantially opposed to each other, the magnetic resistance does not substantially change when viewed in the entire magnetic circuit.

  A mechanism by which the heat medium in the induction heating apparatus 102 is heated will be described. In accordance with the rotation of the rotating body 11, the portion of the fixed magnetic poles 121 to 124 facing the protrusions 111 to 114 of the rotating body 11 moves in the rotation direction, and the distance between the fixed magnetic pole and the rotating body is narrowed. Magnetic flux easily flows from the fixed magnetic poles 121 and 123 to the rotating body 11 or from the rotating body 11 to the fixed magnetic poles 122 and 124. On the other hand, at locations where the distance between the fixed magnetic pole and the rotating body is large, the magnetic flux hardly flows from the fixed magnetic poles 121 and 123 to the rotating body 11 or from the rotating body 11 to the fixed magnetic poles 122 and 124. And in the place where the distance between the fixed magnetic pole and the rotating body becomes narrow, the magnetic flux passing through the heating unit 14 located therebetween increases, while on the other hand, in the place where the distance between the fixed magnetic pole and the rotating body becomes large, The magnetic flux passing through the heating unit 14 positioned therebetween decreases. As a result, the rotation of the rotating body 11 causes the strength of the magnetic field to periodically change over the entire circumference of the heating unit 14, whereby the heating unit 14 is induction-heated and the heat medium in the pipe 15 is heated. In the induction heating device 102, since the heating unit 14 is uniformly heated in the circumferential direction, the pipes 15 are provided at equal intervals in the circumferential direction of the heating unit 14. Although not shown, the heating unit 14 may be covered with a heat insulating material.

  In the induction heating apparatus 102, for example, in the state of FIG. 3A, the magnetic field at the point D in the figure becomes strong because the distance between the fixed magnetic pole and the rotating body becomes narrow, and the magnetic field at the point E in the figure. Becomes weak because the distance between the fixed magnetic pole and the rotating body becomes large. On the other hand, when the rotator 11 rotates, for example, in the state of FIG. 3B, the magnetic field at the point D in the figure becomes weak because the distance between the fixed magnetic pole and the rotator becomes large. The magnetic field of E becomes stronger because the distance between the fixed magnetic pole and the rotating body becomes narrower.

(Embodiment 3)
The induction heating device 103 according to the third embodiment shown in FIG. 4 is different from the induction heating device 102 according to the second embodiment shown in FIG. 3 in the shape of the rotating body and the shape and number of the fixed magnetic poles. The explanation is centered.

  In the induction heating device 103 of FIG. 4, the shape of the rotating body 11 is substantially rectangular, and the fixed magnetic poles are a pair of fixed magnetic poles 121 and 122. Coil elements 131 and 132 are mounted on the fixed magnetic poles 121 and 122, respectively, and the direction of the direct current flowing through the coil elements 131 and 132 is controlled so that the polarity of the fixed magnetic pole 121 is N and the polarity of the fixed magnetic pole 122 is S. Is so magnetized. Then, by applying DC current to the coil elements 131 and 132, a closed magnetic circuit is formed from one fixed magnetic pole 121 to the one fixed magnetic pole 121 again through the rotating body 11, the other fixed magnetic pole 122, and the yoke portion 120. .

  Further, the opposed surface of the fixed magnetic poles 121 and 122 facing the rotating body 11 substantially forms a cylindrical surface centered on the rotation shaft 21, and the interval between the corners on the opposed surface side of one and the other fixed magnetic pole is It is narrower than the width of the protrusion of the rotating body. Therefore, during one rotation of the rotating body 11, the one fixed magnetic pole 121 and the longitudinal end of the rotating body 11, and the longitudinal end of the rotating body 11 and the other fixed magnetic pole 122 are substantially opposed to each other. become. Even if the rotating body 11 rotates, the total magnetic flux flowing in the magnetic circuit formed by the fixed magnetic pole group 12 and the rotating body 11 is substantially constant.

  The mechanism by which the heat medium in the induction heating device 103 is heated is the same as that of the induction heating device 102 in FIG. In accordance with the rotation of the rotating body 11, the portion of the fixed magnetic poles 121 and 122 facing the longitudinal end of the rotating body 11 moves in the rotating direction, and the fixed magnetic pole 121 is moved at a position where the distance between the fixed magnetic pole and the rotating body becomes narrow. The magnetic flux easily flows from the rotating body 11 to the rotating body 11 or from the rotating body 11 to the fixed magnetic pole 122. On the other hand, the magnetic flux hardly flows from the fixed magnetic pole 121 to the rotating body 11 or from the rotating body 11 to the fixed magnetic pole 122 where the distance between the fixed magnetic pole and the rotating body is large. As a result, the rotation of the rotating body 11 causes the strength of the magnetic field to periodically change over the entire circumference in the circumferential direction of the heating unit 14, whereby the heating unit 14 is induction-heated and the heat medium in the pipe 15 is heated. The

  In the induction heating device 103, for example, in the state of FIG. 4A, the magnetic field at the point F in the figure becomes strong because the distance between the fixed magnetic pole and the rotating body becomes narrow, and the magnetic field at the point G in the figure. Becomes weak because the distance between the fixed magnetic pole and the rotating body becomes large. On the other hand, when the rotating body 11 rotates, for example, in the state of FIG. 4B, the magnetic field at the point F in the figure becomes weak because the distance between the fixed magnetic pole and the rotating body becomes large, and the point in the figure The magnetic field of G becomes stronger because the distance between the fixed magnetic pole and the rotating body becomes narrower.

(Embodiment 4)
The induction heating device 104 of the fourth embodiment shown in FIG. 5 is different from the induction heating device 102 of the second embodiment shown in FIG. 3 in the shape of the rotating body, and the difference will be mainly described below.

  In the induction heating device 104 of FIG. 5, the rotating body 11 has a bow shape, and a pair of opposing arc-shaped magnetic material pieces 115 and 116 are supported by a support member 117, and the support member 117 is fixed to the rotation shaft 21. The rotating body 11 is configured. Each of the magnetic material pieces 115 and 116 is made of a magnetic material. In this example, the magnetic material pieces 115 and 116 are formed of laminated steel plates in which silicon steel plates are laminated in the rotation axis direction. Further, the support member 117 has, for example, a rod shape or a flat plate shape, and is made of a nonmagnetic material. Examples of the nonmagnetic material include aluminum, copper, stainless steel such as SUS301 and SUS302, and plastic.

  In this case as well, as with the induction heating device 102 of FIG. 3, during one rotation of the rotating body 11, one of the fixed magnetic poles 121 and 123 and the magnetic material piece of the rotating body 11, and the magnetic material piece of the rotating body 11 and the other The fixed magnetic poles 122 and 124 will substantially always face each other. Therefore, even if the rotating body 11 rotates, the total magnetic flux flowing through the magnetic circuit formed by the fixed magnetic pole group 12 and the rotating body 11 is substantially constant.

  The mechanism by which the heat medium in the induction heating device 104 is heated is the same as that of the induction heating device 102 in FIG. According to the rotation of the rotating body 11, the portion of the fixed magnetic poles 121 to 124 facing the magnetic material piece of the rotating body 11 moves in the rotating direction, and the fixed magnetic pole Magnetic flux easily flows from 121 and 123 to the rotating body 11 or from the rotating body 11 to the fixed magnetic poles 122 and 124. On the other hand, at locations where the distance between the fixed magnetic pole and the rotating body is large, the magnetic flux hardly flows from the fixed magnetic poles 121 and 123 to the rotating body 11 or from the rotating body 11 to the fixed magnetic poles 122 and 124. As a result, the rotation of the rotating body 11 causes the strength of the magnetic field to periodically change over the entire circumference in the circumferential direction of the heating unit 14, whereby the heating unit 14 is induction-heated and the heat medium in the pipe 15 is heated. The

  In the induction heating device 104, for example, in the state of FIG. 5A, one fixed magnetic pole 121 and a part of the magnetic material piece 115 of the rotating body 11 face each other, and the remaining part of the magnetic material piece 115 and the other fixed magnetic pole A magnetic circuit extending from the fixed magnetic pole 121 through the magnetic material piece 115 to the fixed magnetic poles 122 and 124 is formed so that 122 and 124 face each other. Next, when the rotating body 11 rotates, for example, in the state of FIG. 5B, one fixed magnetic pole 121 and a part of the magnetic material piece 115 of the rotating body 11 face each other, and the remaining part of the magnetic material piece 115 A magnetic circuit from the fixed magnetic pole 121 through the magnetic material piece 115 to the fixed magnetic pole 124 is formed facing the other fixed magnetic pole 124. Next, when the rotating body 11 further rotates and, for example, in the state of FIG. 5C, one fixed magnetic pole 121 and a part of the magnetic material pieces 115 and 116 of the rotating body 11 face each other, and the magnetic material piece 115 And the other fixed magnetic poles 122 and 124 face each other, and a magnetic circuit is formed from the fixed magnetic pole 121 through the magnetic material piece 115 to the fixed magnetic poles 122 and 124. Although the description has been made mainly focusing on the fixed magnetic pole 121 here, a magnetic circuit is similarly formed in the other fixed magnetic pole 123.

(Embodiment 5)
The induction heating device 105 of the fifth embodiment shown in FIG. 6 is different from the induction heating device 102 of the second embodiment shown in FIG. 3 in the shape of the rotating body, and the difference will be mainly described below.

  In the induction heating device 105 of FIG. 6, the shape of the rotating body 11 is a gear shape having a plurality of protrusions, and a hole is formed in the central portion as long as the flow of magnetic flux is not hindered. Then, as in the induction heating device 104 of FIG. 5, the rotating body 11 is supported by the support member 117, and the support member 117 is fixed to the rotating shaft 21. In this way, the rotator 11 can be reduced in weight by drilling the rotator 11. Further, for example, when the magnetic material pieces 115 and 116 are used for the rotating body 11 as in the induction heating device 104 of FIG. 5, the weight of the magnetic material pieces is reduced by reducing the thickness of the central portion of the magnetic material pieces within the range not inhibiting the flow of magnetic flux. Is possible.

  Also in this case, as in the induction heating device 102 of FIG. 3, while the rotating body 11 makes one rotation, one of the fixed magnetic poles 121 and 123 and the protrusion of the rotating body 11, and the protrusion of the rotating body 11 and the other fixed magnetic pole 122 and 124 are substantially always opposite. Therefore, even if the rotating body 11 rotates, the total magnetic flux flowing through the magnetic circuit formed by the fixed magnetic pole group 12 and the rotating body 11 is substantially constant.

  The mechanism by which the heat medium in the induction heating device 105 is heated is the same as that of the induction heating device 102 in FIG. In accordance with the rotation of the rotating body 11, the portions of the fixed magnetic poles 121 to 124 that face the protrusions of the rotating body 11 move in the rotation direction, and the fixed magnetic poles 121 and 123 are fixed at locations where the distance between the fixed magnetic pole and the rotating body is narrow. The magnetic flux easily flows from the rotating body 11 to the rotating body 11 or from the rotating body 11 to the fixed magnetic poles 122 and 124. On the other hand, at locations where the distance between the fixed magnetic pole and the rotating body is large, the magnetic flux hardly flows from the fixed magnetic poles 121 and 123 to the rotating body 11 or from the rotating body 11 to the fixed magnetic poles 122 and 124. As a result, the rotation of the rotating body 11 causes the strength of the magnetic field to periodically change over the entire circumference of the heating unit 14, whereby the heating unit 14 is induction-heated and the heat medium in the pipe 15 is heated.

  In addition, in the induction heating device 105, the cycle of the magnetic field can be shortened by making the shape of the rotating body 11 into a gear shape.

  In the induction heating devices 101 to 105 according to the first to fifth embodiments described above, the flow path is formed in the heating unit 14 and the heating unit 14 and the pipe 15 are integrally formed. The part 14 and the pipe 15 may be formed separately. In that case, it is preferable that the pipe is also formed of a conductive material. By forming the pipe with a conductive material, the pipe can also be used as a heating unit. Moreover, a heating part and piping may be made into a different body, and piping may be provided in the surface of a heating part. Here, when the pipe is formed of a conductive material and the pipe is also used as a heating unit, for example, the pipe may be attached to the surface of a cylindrical support base in addition to the pipe. At this time, the cylindrical support base may be formed of a material other than the conductive material.

  Since the induction heating apparatus according to the embodiment of the present invention described above uses a coil as the magnetic field generating means, it can generate a stronger magnetic field as compared with a conventional apparatus using a permanent magnet. In particular, by adopting a superconducting coil, it is possible to suppress the heat generation of the coil caused by flowing a large current, and it is possible to generate a stronger magnetic field. In addition, since the heating part (pipe) does not rotate, for example, a rotary joint that allows rotation of the pipe to connect the pipe to the supply / discharge pipe that communicates with the pipe and supplies and discharges the heat medium from the outside. There is no need to use a simple connection, and a robust connection can be realized.

<Power generation system>
Next, an example of the overall configuration of the power generation system according to the present invention will be described with reference to FIG. The power generation system P shown in FIG. 7 includes an induction heating device 10, a windmill 20, a heat accumulator 50, and a power generation unit 60. The wind turbine 20 is attached to a nacelle 92 installed at the upper part of the tower 91, and the induction heating device 10 is stored in the nacelle 92. Further, the heat accumulator 50 and the power generation unit 60 are installed in a building 93 built at the lower part (base) of the tower 91. Hereinafter, the configuration of the power generation system P will be described in detail.

  The induction heating device 10 is the induction heating device of the present invention, and for example, the induction heating devices 101 to 105 according to the first to fifth embodiments described above can be used. Further, the rotating shaft 21 is directly connected to a windmill 20 described later, and wind power is used as power for rotating the rotating body. Here, a case where the heat medium is water will be described as an example.

  The windmill 20 has a structure in which three blades 201 are radially attached to the rotary shaft 21 around a rotary shaft 21 extending in the horizontal direction. In the case of a wind power generation system with an output exceeding 5 MW, the diameter is 120 m or more and the rotation speed is about 10 to 20 rpm.

  Connected to the piping of the induction heating apparatus 10 are a water supply pipe 73 that supplies water to the induction heating apparatus 10 and a transport pipe 51 that sends the water heated by the induction heating apparatus 10 to the regenerator 50. Then, the induction heating device 10 forms a magnetic circuit between the fixed magnetic pole group and the rotating body by direct current energization of the coil, and passes through a heating unit disposed between the fixed magnetic pole and the rotating body by the rotation of the rotating body. The heating part is induction-heated by changing the magnetic flux to be heated, and the water in the pipe is heated. Since the induction heating apparatus 10 uses a coil as the magnetic field generating means, it can generate a strong magnetic field and can heat water as a heat medium to a high temperature such as 100 ° C. to 600 ° C. In addition, since the induction heating device 10 has a structure in which the heating unit (pipe) does not rotate, it is not necessary to use a rotary joint for connecting the pipe to the transport pipe 51 and the water supply pipe 73. With a simple configuration, a robust connection can be realized.

  In the power generation system P, water is heated to, for example, 200 ° C. to 350 ° C. by the induction heating device 10 to generate high-temperature and high-pressure water. The high-temperature high-pressure water is sent to the regenerator 50 through a transport pipe 51 that connects the induction heating device 10 and the regenerator 50. The heat accumulator 50 stores the heat of the high-temperature and high-pressure water sent through the transport pipe 51, and supplies steam necessary for power generation to the power generation unit 60 using a heat exchanger. Note that steam may be generated by the induction heating device 10.

  As the heat accumulator 50, for example, a steam accumulator, a sensible heat type using a molten salt or oil, or a latent heat type heat accumulator using a phase change of a molten salt having a high melting point can be used. Since the latent heat type heat storage method stores heat at the phase change temperature of the heat storage material, the heat storage temperature range is generally narrower than that of the sensible heat type heat storage method, and the heat storage density is high.

  The power generation unit 60 has a structure in which a steam turbine 61 and a generator 62 are combined. The steam turbine 61 is rotated by the steam supplied from the heat accumulator 50, and the generator 62 is driven to generate power.

  The high-temperature high-pressure water or steam sent to the regenerator 50 is cooled by the condenser 71 and returned to the water. After that, it is sent to the pump 72 and is circulated by being made into high-pressure water and sent to the induction heating device 10 through the water supply pipe 73.

  According to this power generation system P, it is possible to generate rotational energy by using renewable energy (eg, wind power) as power, generate heat, and store the heat in a heat accumulator to generate electricity, so that an expensive storage battery is not used. However, stable power generation according to demand can be realized. Further, it is not necessary to provide a speed increaser unlike the conventional wind power generation system, and it is possible to avoid a gearbox trouble. Furthermore, by supplying the heat of the heat medium to the power generation unit installed in the lower part (base) of the tower, for example, by a transport pipe, there is no need to store the power generation part in the nacelle, and the nacelle installed in the upper part of the tower is made small -It can be reduced in weight.

  In the power generation system described above, the case where water is used as the heat medium has been described as an example. However, a liquid metal having a higher thermal conductivity than water may be used as the heat medium. An example of such a liquid metal is liquid metal sodium. When using a liquid metal as a heat medium, for example, the liquid metal is used as a primary heat medium that receives heat from a conductor, and the heat of the liquid metal sent through the transport pipe is used as a secondary heat via a heat exchanger. It is conceivable that the medium (water) is heated to generate steam.

  Note that the present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the gist of the present invention. For example, the shape of the rotating body and the shape and number of the fixed magnetic poles can be changed as appropriate, and the material forming the rotating body and the fixed magnetic poles can be changed as appropriate.

  The induction heating apparatus of the present invention can be used for a hot water supply system, for example, in addition to being used for a power generation system using renewable energy. Moreover, the power generation system of the present invention can be suitably used in the field of power generation using renewable energy.

10, 101-105 Induction heating device P Power generation system
11 Rotating body 111-114 Projection 115,116 Magnetic material piece 117 Support member
12 Fixed magnetic pole group 120 Yoke part 121-124 Fixed magnetic pole
13 Coil 131,132,133,134 Coil element
14 Heating part 15 Piping 16 Heat insulation
21 Rotation axis
20 Windmill 201 Wings
50 Heat storage unit 51 Transport pipe
60 Power generation section 61 Steam turbine 62 Generator
71 Condenser 72 Pump 73 Water supply pipe
91 Tower 92 Nasser 93 Building

Claims (6)

A rotating body made of a magnetic material fixed to the rotating shaft and having a non-circular outer shape;
At least a pair of fixed magnetic poles disposed on the outer periphery of the rotating body so as to face the rotating body and having different polarities;
A coil provided on the fixed magnetic pole for generating a DC magnetic field;
A heating unit disposed between the fixed magnetic pole and the rotating body and made of a conductive material;
A pipe provided in the heating unit and through which a heat medium flows,
A magnetic circuit that passes through one of the fixed magnetic poles, the rotating body, and the other fixed magnetic poles is formed by direct current energization of the coil,
Due to the rotation of the rotating body, the magnetic flux passing through at least a part of the heating unit disposed between the fixed magnetic pole and the rotating body changes, whereby the heating unit is induction-heated, and the heating medium is An induction heating device characterized by heating. While the rotating body makes one rotation, the one fixed magnetic pole and the rotating body, and the rotating body and the other fixed magnetic pole are substantially always opposed to each other.
2. The induction heating apparatus according to claim 1, wherein even if the rotating body rotates, a total magnetic flux flowing in a magnetic circuit formed by the fixed magnetic pole and the rotating body is substantially constant.   The induction heating device according to claim 1 or 2, wherein when the fixed magnetic pole and the rotating body face each other, the area of the rotating body is smaller than the fixed magnetic pole.   The induction heating apparatus according to claim 1, wherein the coil is a superconducting coil. The rotating shaft is connected to a windmill;
The induction heating apparatus according to any one of claims 1 to 4, wherein wind power is used as power for rotating the rotating body. Induction heating apparatus according to any one of claims 1 to 5,
And a power generation unit that converts heat of the heat medium into electrical energy.

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