JP2007071104A - Heat power generation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat power generation system which realizes long-term rotation of a turbine independently of the kind of a working medium, starts the rotation smoothly, and also controls a bearing comparatively easily. <P>SOLUTION: The working medium is directly or indirectly heated by a collector absorbing heat energy, and steam of the working medium is ejected from a nozzle 8 to rotationally drive the turbine 5 with high pressure steam from a nozzle 8. A power generator rotor 6A in a power generator 6 is rotated by the rotation of the turbine 5 so that electric power is generated by a power generator stator 6B facing the power generator rotor 6A. A main shaft 7 to connect a blade wheel 5a of the turbine 5 and the power generator rotor 6A is partially supported for one part of the main shaft 7 by electromagnets 14 and 15, and supported for the other part of the main shaft 7 by a non-contact bearing supported by permanent magnets 12 and 13. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermoelectric generation system that converts thermal energy such as solar heat into electric energy.

As a conventional example of this type of thermal power generation system, a solar thermal power generation system is known in which a working medium is heated by solar heat, a turbine is rotated by high-pressure steam of the working medium, and a generator is generated by the rotation of the turbine. (For example, Patent Documents 1 to 3).
JP 2002-242893 A JP 2000-110515 A JP 2003-227315 A

In each of the solar thermal power generation systems described above, since the obtained thermal energy is small and the energy density is low, an organic medium that is easily vaporized or an organic medium having a low boiling point (for example, ammonia, chlorofluorocarbon, alcohol, acetone, etc.) is used as the working medium. used. However, when such a working medium is used, there is a problem in that it is difficult to hold the lubricant for the bearing for rotating and supporting the turbine because of high heat, and it cannot be rotated for a long time.
As an example of measures for solving this problem, for example, it is conceivable to rotationally support the turbine using a dynamic pressure bearing or a foil bearing. However, in these bearings, since the bearing portion is in mechanical contact with the turbine in a stopped state, there is a problem that the rotation starting torque is large and rotation starting is difficult.

Further, there are the following problems with respect to the rotation support of the main shaft of the turbine of the thermoelectric generation system.
・ Although there is a method to lift the rotating part completely without contact with only an electromagnet, it is necessary to perform five-axis control for levitation. At the same time, the number of electromagnets increases, the controller configuration is complicated, and the cost increases. .
-Even when a part of the main shaft is supported using the repulsive force of the permanent magnet, if the main shaft is only controlled by position control, the amount of power supplied to the electromagnet increases, and this power consumption must be reduced.
-In the configuration using an electromagnet for axial support, two electromagnets are required. Therefore, it becomes a subject to aim at cost and compactization.
The support stiffness by the electromagnet is large, but the passive shaft (radial stiffness for the axial support electromagnet / axial stiffness for the radial support electromagnet) is small. In order to float the spindle stably, it is necessary to increase this passive rigidity.
The support stiffness by the electromagnet is large, but the passive axis (radial stiffness for the axial support electromagnet / axial stiffness for the radial support electromagnet) is small. On the other hand, the attractive force between the generator stator and the generator rotor acting as a disturbance to the main shaft is large and needs to be supported.
-There exists a problem that the coil of a generator stator part or the mold resin which protects this coil deteriorates with the solvent used for a working medium.
Also, there is a problem that the working medium remains in the unit and the working medium cannot be used effectively.
-In solar thermal power generation, since the obtained heat energy is small and the energy density is low, there is a problem that it is difficult to start rotation if the mass and moment of inertia of the turbine member are large.
The thermoelectric power generation system is a system that generates power based on the temperature difference of the working medium. However, using a dedicated device for cooling the working medium increases the system cost.

An object of the present invention is to provide a thermoelectric power generation system in which a turbine can be rotated for a long period of time without being limited by the type of working medium, rotation can be started smoothly, and bearings can be controlled relatively easily.
Another object of the present invention is to solve the above problems.

In the thermoelectric generation system of the present invention, the working medium is directly or indirectly heated by the collector that absorbs thermal energy, the steam of the working medium is ejected from the nozzle, and the turbine is rotationally driven by the high-pressure steam from the nozzle. The turbine impeller of the turbine, the generator rotor, and the generator rotor portion of the generator that is provided opposite to the generator rotor by rotating the generator rotor of the generator by the rotation of the turbine. The non-contact bearing has a structure in which a portion of the main shaft is supported by an electromagnet.
This thermoelectric power generation system may be a solar thermal power generation system that uses solar heat as thermal energy. The non-contact bearing is a magnetic bearing that supports the other part of the main shaft using, for example, a permanent magnet.

According to this configuration, since the main shaft is rotatably supported, a part of the main shaft is supported by the electromagnet and the other part is also supported by the permanent magnet, so that the bearing lubricant is unnecessary. Therefore, there is no problem in bearing lubrication even if an organic solvent that easily vaporizes, such as ammonia, alternative chlorofluorocarbon, alcohol, or acetone, or an organic solvent having a low boiling point is used as the working medium. As a result, the turbine can be rotated for a long time without being limited by the type of working medium.
In addition, since the main shaft is supported by the electromagnet and the permanent magnet so that the main shaft can float even when the main shaft is not rotating, the rotation starting torque is small and wear does not occur, and the rotation can be started smoothly.
It is possible to support the main shaft in a non-contact state using only electromagnets, but in that case, multi-axis control is required to lift the main shaft, and at the same time the number of electromagnets increases, The configuration also becomes complicated and causes an increase in cost. On the other hand, by using a configuration in which an electromagnet is partially used as described above, the control is simple and the cost can be reduced.

In the present invention, the non-contact bearing is formed by a repulsive force between a first permanent magnet provided on the main shaft and a second permanent magnet disposed on the fixed side opposite to the first permanent magnet, and an attractive force of the electromagnet. The main shaft may be supported.
By using a bearing that is supported by the repulsive force between the permanent magnets and the attractive force of the electromagnet, the spindle can be supported so as to be able to levitate even when not rotating, with a simple configuration. By combining the support by the repulsive force between the permanent magnets and the support by the attraction force of the electromagnet, the non-contact support of the spindle with a simple structure can be performed stably.

  As described above, when the first and second permanent magnets and the electromagnet are used together, the repulsive force between the first permanent magnet and the second permanent magnet acts in the radial direction perpendicular to the rotation axis of the turbine. The axial direction may be supported by the electromagnet. In the case of this configuration, the electromagnet can be configured only by the yoke and the ring-shaped coil winding, and can be configured at low cost.

  Further, when the first and second permanent magnets and the electromagnet are used in combination as described above, the main shaft is moved in the axial direction by shifting the facing surfaces of the first permanent magnet and the second permanent magnet. The force may be applied only in one direction, and in this state, the electromagnet may be arranged only in the direction in which the axial force by the permanent magnet is canceled. In the case of this configuration, the number of electromagnets can be reduced from two to one, and the configuration can be simplified.

  In this invention, it is good also as what has a sensor which detects the position of a main axis | shaft, and a means to change the electric current of the said electromagnet by the detection value of this sensor. In the case of this configuration, the main shaft can be easily positioned in the axial direction, or can be stably supported in the radial direction.

  In the present invention, a flange portion may be provided on the main shaft, and the electromagnet may be provided to face the flange portion. By providing the flange portion on the main shaft as described above, the configuration of supporting the main shaft in the thrust direction by the attractive force of the electromagnet is simplified by disposing the electromagnet opposite to the flange portion in the axial direction.

  In the present invention, a protrusion may be provided on the end face of the main shaft facing the electromagnet so that the magnetic flux is concentrated from the electromagnet. When the protrusions are provided in this way, a passive spring support system is formed in the radial direction by the magnetic flux concentrated on the protrusions. Although the support rigidity in the axial direction of the main shaft is increased by the attractive force of the electromagnet, the support rigidity in the radial direction is small because it is supported by the repulsive force of the permanent magnet. In order to increase the support rigidity in the radial direction, a passive spring support system in the radial direction obtained by the protrusion is effective, and thereby the main shaft can be stably supported without contact.

  In this invention, the generator rotor and the generator stator may be the same as the opposing direction of the electromagnet and the main shaft. In the case of this configuration, the disturbance of electromagnetic attraction due to power generation does not reach the radial direction where the support rigidity is small, but occurs in the thrust direction where the support rigidity is high. Therefore, the influence of power generation disturbance on the main shaft can be suppressed as much as possible.

  In this invention, it is good also as what has a partition in a part between the rotation part and stationary part of the said generator. Thus, by providing a partition wall in a part between the rotating part and the stationary part of the generator, the insulating film on the surface of the coil in the generator stator part and the mold resin that protects the coil are organic working mediums. It is possible to avoid a situation where stable power generation cannot be performed due to being attacked by a solvent or the like.

  In this invention, you may install the said main axis | shaft of the said unit with respect to a horizontal surface so that the said working medium may be discharged | emitted by the dead weight from the unit which consists of the said turbine, a generator, and a main axis | shaft. In this way, the unit's main shaft is inclined with respect to the horizontal plane, and the working medium is discharged from the unit by its own weight, so that even if the working medium that has passed through the turbine has condensed in the unit, The liquefied working medium tends to flow out. For this reason, it is possible to prevent the liquefied working medium from entering the generator portion or coming into contact with the electromagnet or the like as the bearing portion to reduce the energy conversion efficiency.

In this invention, the turbine impeller may be made of a plastic material that is not affected by the working medium. If the turbine impeller is made of plastic, the weight of the turbine impeller can be reduced, so that it can be rotated even with a small jet power. Even if a plastic material is used, there is no problem by using a material that is not affected by the working medium.
For example, the plastic material may be a PEEK material (polyether ether ketone material). The PEEK material is an engineering plastic excellent in heat resistance, flame retardancy, and chemical resistance, and is excellent in various aspects as a material for a turbine impeller.

  In the present invention, the turbine may liquefy the high-pressure steam by a cooling action accompanying expansion. When the working medium is cooled in the turbine as described above, a dedicated device for cooling the working medium is not necessary, and the cost can be reduced accordingly.

In this invention, it has means for measuring the pressure of the working medium between the collector and the nozzle, the temperature of the collector, or the amount of heat input to the collector, and the measured pressure or temperature or amount of heat is a predetermined value. When the value is below the threshold value, the electromagnet may be provided with means for preventing current from flowing.
When the thermoelectric generator system is a solar thermoelectric generator system, for example, the time period in which the collector can absorb solar heat as effective thermal energy is limited. Therefore, as described above, the pressure of the working medium, the temperature of the collector, or the amount of heat input to the collector is measured, and at night when the measured pressure, temperature, or amount of heat falls below a predetermined threshold, current is supplied to the electromagnet. If it is not allowed to flow, it is possible to avoid wasting power and supporting the spindle by the electromagnet at night when effective solar heat cannot be obtained.

  In the thermoelectric generation system of the present invention, the working medium is directly or indirectly heated by the collector that absorbs thermal energy, the steam of the working medium is ejected from the nozzle, and the turbine is rotationally driven by the high-pressure steam from the nozzle. The turbine impeller of the turbine, the generator rotor, and the generator rotor portion of the generator that is provided opposite to the generator rotor by rotating the generator rotor of the generator by the rotation of the turbine. The non-contact bearing has a structure in which a part of the main shaft is supported by an electromagnet so that the turbine can be rotated for a long time without being restricted by the type of working medium. The start-up can be performed smoothly and the bearing control can be made relatively simple.

A first embodiment of the present invention will be described with reference to FIGS. This thermoelectric power generation system is a solar thermal power generation system that converts solar heat, which is thermal energy, into electric energy and outputs the electric energy, and includes a collector 1 that absorbs solar heat, a turbine 5 and a generator 6 as shown in FIG. A turbine unit 2 and a working medium circulation path 4 for circulating the working medium 3 between the collector 1 and the turbine 5 are provided.
The working medium circulation path 4 was used to rotate the turbine 5 and the nozzle 8 for rotating the turbine 5 by jetting the steam of the working medium 3 directly heated by the collector 1 to the turbine 5 as high-pressure steam. And a pump 9 for circulating and supplying the working medium 3 to the collector 1.

  The generator 6 of the turbine unit 2 includes a generator rotor 6A that is a rotating portion and a generator stator portion 6B that is a stationary portion. The impeller (not shown in FIG. 1) of the turbine 5 and the generator rotor 6 </ b> A are connected by a main shaft 7. The main shaft 7 is rotatably supported by a bearing 11. Specifically, the generator 6 is an axial gap generator, and a generator rotor 6A is provided on an outer peripheral portion of a thrust plate 7a that is a circular flange portion provided at one end of the main shaft 7, and this generator rotor 6A is provided. A pair of generator stator portions 6B and 6B are arranged opposite to each other with a predetermined gap in the axial direction. An impeller of the turbine 5 is connected to the other end of the main shaft 7. Thus, the rotation of the turbine impeller becomes the rotation of the generator rotor 6A, and power is generated by the generator stator portion 6B provided to face the generator rotor 6A. This power generation is controlled by the controller 10.

  2 shows an enlarged cross-sectional view of the turbine unit 2 in FIG. 1, and FIG. 3 shows a cross-sectional view taken along the line III-III in FIG. In FIG. 2, a cylindrical nozzle member 18 having one end opened is fixedly installed through a minute gap on the inner periphery of the turbine impeller 5 a connected to the other end of the main shaft 7. A plurality of nozzles 8 penetrating toward the turbine blade 5aa of the vehicle 5a are provided in the circumferential direction. The open end of the nozzle member 18 is connected to the upstream portion of the working medium circulation path 4 and serves as an air supply port 19 through which the working medium 3 heated by the collector 1 flows. On the outer peripheral side of the turbine impeller 5 a, an exhaust port 20 through which the working medium 3 that gives rotational energy to the turbine impeller 5 a flows out to the downstream portion of the working medium circulation path 4 penetrates the unit housing 2 a of the turbine unit 2. Is provided.

  The turbine 5 is made of a plastic material that is not affected by the working medium 3. In particular, the turbine impeller 5a of the turbine 5 is made of the plastic material. As the plus chip material in this case, for example, a PEEK material (polyether ether ketone material) or the like is suitable. When the turbine impeller 5a is made of a plastic material, the weight can be reduced, so that the turbine impeller 5a can be rotated even with a small jet power. Even if a plastic material is used, no trouble is caused by using a material that is not affected by the working medium 3. The PEEK material is an engineering plastic excellent in heat resistance, flame retardancy, and chemical resistance, and is excellent in various aspects as the material of the turbine 5.

  The bearing 11 that supports the main shaft 7 is partially made of an electromagnet, and includes a radial bearing portion 11A that supports the main shaft 7 in the radial direction and a thrust bearing portion 11B that supports the main shaft 7 in the axial direction. Here, the radial bearing portion 11A is a magnetic bearing using a permanent magnet as follows.

  The radial bearing portion 11A includes a first permanent magnet 12 provided on the outer periphery of the main shaft 7 on the rotation side, and a second permanent magnet 13 provided on the inner periphery of the unit housing 2a on the fixed side so as to face the first permanent magnet 12. And become. These permanent magnets 12 and 13 are arranged with their polar directions determined so that their opposing surfaces have the same magnetic pole. As a result, a repulsive force acts between the first permanent magnet 12 and the second permanent magnet 13 in the radial direction perpendicular to the axis of the main shaft 7 (that is, the rotating shaft of the turbine 5), and the main shaft 7 is brought into a non-contact state. Support in the radial direction. In addition, the radial bearing portion 11A in this case is configured by arranging a plurality of sets (here, two sets) of combinations of the first permanent magnet 12 and the second permanent magnet 13 in the axial direction.

  The thrust bearing portion 11 </ b> B is composed of a pair of electromagnets 14 and 15 that are disposed to face each other in the axial direction across a thrust plate 7 a that is a flange portion of the main shaft 7. The electromagnets 14 and 15 are disposed inside the unit housing 2a and are opposed to both side surfaces of the thrust plate 7a. The yokes 14a and 15a are embedded in the yokes 14a and 15a and are ring-shaped around the axis of the main shaft 7. Coil windings 14b and 15b. In this case, the thrust plate 7a is made of a magnetic material. Thereby, the attractive force of each electromagnet 14 and 15 acts on the opposing side surface of the thrust plate 7a, and the main shaft 7 is supported in the thrust direction in a non-contact state. Thus, the thrust plate 7a which is a flange part is provided in the main shaft 7, and the electromagnets 14 and 15 are disposed opposite to each other in the axial direction across the thrust plate 7a, so that the thrust direction of the main shaft 7 due to the attractive force of the electromagnets 14 and 15 The support structure is simplified.

Further, projections 7aa are provided on the end face of the main shaft (specifically, both side surfaces of the thrust plate 7a), and the projections 7aa are provided on the surfaces of the yokes 14a, 15a of the electromagnets 14, 15 facing the both sides of the thrust plate 7a. Protrusions 14aa and 15aa are provided to face each other. As a result, the magnetic flux generated by the electromagnets 14 and 15 preferentially passes between the projections 7aa and 14aa and between the projections 7aa and 15aa. A spring support system is configured.
A sensor target 17 is provided at the position of the main shaft axis on the side surface of the thrust plate 7 a facing the electromagnet 14, and a sensor for detecting the axial position of the main shaft 7 facing the sensor target 17 on the surface of the yoke 14 a of the electromagnet 14. 16 is provided. The controller 10 shown in FIG. 1 is provided with means for positioning the main shaft 7 at a predetermined position in the axial direction by controlling the coil current flowing through the coil windings 14b and 15b of the electromagnets 14 and 15 according to the detection value of the sensor 16. It is done.

  The end of the turbine impeller 5a opposite to the end connected to the main shaft 7a is supported in a non-contact state by a magnetic bearing having the same configuration as the radial bearing 11A. That is, the first permanent magnet 12A provided on the outer periphery of the end portion of the turbine impeller 5a on the rotating side and the inner periphery of the unit housing 2a on the fixed side are provided to face the permanent magnet 12A in the radial direction. The end portion of the turbine impeller 5a is supported in a non-contact state by the repulsive force acting between the second permanent magnet 13A.

  Next, operation | movement of the solar thermal power generation system of this structure is demonstrated. The working medium 3 in the working medium circulation path 4 is directly heated by the collector 1 that absorbs solar heat to become high-pressure steam, and this high-pressure steam is injected to the turbine impeller 5 a of the turbine 5 through the nozzle 8. Thereby, the turbine 5 is rotationally driven. The generator rotor 6A is rotated by the rotation of the turbine 5, and electric power is generated by the generator stator portion 6B provided to face the generator rotor 6A. In this way, the rotation of the turbine 5 is converted into electric energy.

  The working medium 3 that has given rotational energy to the turbine 5 is transported to the collector 1 by the pump 9, but is cooled from the turbine 5 to the pump 9 and completely returned to liquid. At this time, it is desirable for the turbine 5 to liquefy the high-pressure steam of the working medium 3 by a cooling action accompanying adiabatic expansion. As a result, a dedicated device for cooling the working medium 3 becomes unnecessary, and the cost can be reduced accordingly.

  The main shaft 7 is a thrust bearing portion 11B while being rotatably supported in a non-contact state in the radial direction by a repulsive force between the first permanent magnet 12 and the second permanent magnet 13 constituting the radial bearing portion 11A. The electromagnets 14 and 15 are supported at predetermined positions in the axial direction by the attractive force with respect to both side surfaces of the thrust plate 7a which is the main shaft end surface.

Thus, in this solar thermal power generation system, since the main shaft 7 is rotatably supported in a non-contact state, a lubricant for the bearing becomes unnecessary. Therefore, even if ammonia, an organic solvent that is easily vaporized, such as alternative chlorofluorocarbon, alcohol, or acetone, or an organic solvent having a low boiling point is used as the working medium 3, there is no problem in lubricating the bearing. As a result, the turbine 5 can be rotated for a long time without being limited by the type of the working medium 3.
In addition, since a part of the main shaft 7 is supported by the electromagnets 14 and 15 and the other parts are supported by the permanent magnets 12 and 13, the main shaft 7 is supported in a non-contact state even when the rotation of the main shaft 7 is stopped. Therefore, the rotation starting torque is small, there is no wear, and the rotation starting can be performed smoothly.

  For example, when a dynamic pressure bearing or a foil bearing is used to support the main shaft 7, the fluid pressure between the bearing stationary side and the bearing rotation side increases as the main shaft 7 rotates. Since the main shaft 7 can be passively supported as a contact bearing, it is suitable for such a power generation system in which the rotational torque is small and energy loss is to be reduced as much as possible. However, in the case of a dynamic pressure bearing or a foil bearing, when the main shaft 7 is not rotating, the bearing stationary side and the bearing rotating side are in mechanical contact with each other. . In addition, there is a problem in long-term durability, such as friction caused by relative sliding between the bearing stationary side and the bearing rotating side when the rotation is started.

  Although it is possible to support the main shaft 7 in a non-contact state using only electromagnets, in that case, five-axis control is required to float the main shaft 7, and the number of electromagnets increases. At the same time, the configuration of the controller 10 becomes complicated, resulting in an increase in cost. On the other hand, it is possible to reduce the cost by using a configuration in which the electromagnets 14 and 15 are partially used as described above.

  Further, in this embodiment, the main shaft 7 is supported in the radial direction by the repulsive force of the first permanent magnet and the second permanent magnet, and the main shaft 7 is supported in the thrust direction by the attractive force of the electromagnets 14 and 15. Therefore, the electromagnets 14 and 15 can be configured only by the yokes 14a and 15a and the ring-shaped coil windings 14b and 15b, and can be configured at low cost.

  In this embodiment, projections 7aa are provided on the end face of the main shaft (specifically, both side surfaces of the thrust plate 7a), and the yokes 14a, 15a of the electromagnets 14, 15 are opposed to both side surfaces of the thrust plate 7a. Protrusions 14aa and 15aa opposed to the protrusion 7aa are provided on the surface. Therefore, the magnetic flux generated by the electromagnets 14 and 15 passes preferentially between the projections 7aa and 14aa and between the projections 7aa and 15aa. A support system is constructed. Although the support rigidity in the axial direction of the main shaft 7 is increased by the attractive force of the electromagnets 14 and 15, the support rigidity in the radial direction is small because it is supported by the repulsive force of the permanent magnet. In order to increase the support rigidity in the radial direction, a passive spring support system in the radial direction obtained by the projections 7aa, 14aa, 15aa is effective, and the main shaft 7 can be stably supported in a non-contact manner.

  Moreover, in this embodiment, the sensor target 17 is provided in the main shaft axial center position of the side surface facing the electromagnet 14 of the thrust plate 7a. By detecting the sensor target 17 with the sensor 16 provided on the surface of the yoke 14a of the electromagnet 14, the position in the axial direction of the main shaft 7 is detected, and the detected values flow through the coil windings 14b and 15b of the electromagnets 14 and 15. The coil current is controlled to position the main shaft 7 at a predetermined position in the axial direction. Therefore, it is possible to easily position the main shaft 7 in the axial direction.

  In this embodiment, the facing direction of the generator rotor 6A and the generator stator portion 6B is the same as the facing direction (thrust direction) of the electromagnets 14 and 15 and the main shaft 7 (specifically, the main shaft thrust plate 7a). Therefore, electromagnetic attraction disturbance due to power generation does not reach the radial direction where the support rigidity is small, but occurs in the thrust direction where the support rigidity is high. Therefore, the influence of power generation disturbance on the main shaft 7 can be suppressed as much as possible.

In the above embodiment, a measuring means for measuring the pressure of the working medium 3 between the collector 1 and the nozzle 8 in the working medium circulation path 4, the temperature of the collector 1, or the amount of heat input to the collector 1 is provided. Means may be provided for preventing current from flowing through the electromagnets 14 and 15 when the measured pressure, temperature, or heat quantity is below a predetermined threshold.
The thermoelectric generation system of the above embodiment is a solar thermal power generation system, and the time zone in which the collector 1 can absorb solar heat as effective thermal energy is limited. Therefore, as described above, the pressure of the working medium 3, the temperature of the collector 1, or the amount of heat input to the collector 1 is measured by the measuring means, and the measured pressure, temperature, or amount of heat falls below a predetermined threshold at night or the like. If no current is passed through the electromagnets 14 and 15, it is possible to avoid consuming unnecessary power and supporting the main shaft 7 by the electromagnets 14 and 15 at night when effective solar heat cannot be obtained.

FIG. 4 is an enlarged cross-sectional view showing another example of the turbine unit 2. In the example of the turbine unit 2, the partition wall 21 is provided in a part between the rotating portion and the stationary portion of the generator 6 in the turbine unit 2 of FIG. 2. Specifically, the surface spanning the electromagnets 14 and 15 from the generator stator 6B, which is a stationary part of the generator 6, is covered and protected by the partition wall 21. In this example, the electromagnets 14 and 15 and the protrusions 14aa, 15aa and 7aa (FIG. 2) of the main shaft thrust plate 7a are not provided. Other configurations are the same as the example of FIG.
In this way, by providing the partition wall 21 at a part between the rotating part and the stationary part of the generator 6, the insulating film on the coil surface of the generator stator part 6 </ b> B and the electromagnets 14 and 15 is the organic medium that is the working medium 3. It is possible to avoid a situation in which stable power generation or spindle support cannot be performed due to being attacked by a solvent or the like.

FIG. 5 is an enlarged cross-sectional view showing still another example of the turbine unit 2. In the example of this turbine unit 2, in the turbine unit 2 of FIG. 4, the 1st permanent magnet 12 provided in the outer periphery of the main shaft 7, and the 2nd permanent magnet 13 provided in the inner periphery of the unit housing 2a which is a stationary side. The one facing one of the electromagnets 14 and 15 is omitted (here, the electromagnet 14 is omitted). That is, the first permanent magnet 12 and the second permanent magnet 13 cause a force to act on the main shaft 7 only in one axial direction, and this axial force is canceled by the attractive force of the electromagnet 15. Yes. In the figure, an axial force always acts on the left side of the main shaft 7 due to the repulsive force of the permanent magnets 12 and 13, and the attractive force of the electromagnet 15 acts on the right side as an axial force. On the contrary, the permanent magnets 12 and 13 may be provided so as to be shifted so that the repulsive force of the permanent magnets 12 and 13 becomes the right axial force, and the axial force may be canceled by the attractive force of only the electromagnet 14. Other configurations are the same as the example of FIG.
With this configuration, the number of electromagnets can be reduced from two to one, and the configuration can be simplified.

6 is an enlarged sectional view showing still another example of the turbine unit 2, and FIG. 7 is a sectional view taken along arrow VII-VII in FIG. In the example of the turbine unit 2, in the turbine unit 2 of FIG. 2, a cylindrical nozzle member 18 is fixedly installed on the outer periphery of the impeller 5 a of the turbine 5 through a minute gap, and the turbine impeller 5 a is attached to the nozzle member 18. A plurality of nozzles 8 penetrating toward the turbine blade 5aa are distributed in the circumferential direction. On the outer peripheral side of the nozzle member 18, an air supply port 19 connected to the upstream portion of the working medium circulation path 4 and through which the working medium 3 heated by the collector 1 flows is provided through the unit housing 2 a of the turbine unit 2. ing. An exhaust port 20 through which the working medium 3 that gives rotational energy to the turbine impeller 5 a flows out to the downstream part of the working circuit 4 is opened at the rotation center of one end of the turbine 5. In this example, the electromagnets 14 and 15 and the protrusions 14aa, 15aa and 7aa (FIG. 2) of the main shaft thrust plate 7a are not provided. Other configurations are the same as the example of FIG.
In the turbine unit 2 configured as described above, the steam of the working medium 3 flowing from the air supply port 19 is injected from the nozzle 8 on the outer peripheral side of the turbine impeller 5a to the turbine impeller 5a, whereby the turbine 5 is Driven by rotation. The working medium 3 that has passed through the turbine impeller 5 a is discharged to the outside of the turbine unit 2 from the exhaust port 20 on the inner peripheral side of the turbine 5.

FIG. 8 is an enlarged cross-sectional view showing still another example of the turbine unit 2. In the example of the turbine unit 2, in the turbine unit 2 of FIG. 2, the main shaft 7 of the turbine unit 2 is inclined with respect to the horizontal plane so that the end on the air supply port 19 side faces downward, and the exhaust port By providing 20 at a position deviated downward from the axis of the main shaft 7, the working medium 3 is discharged from the turbine unit 2 through the exhaust port 20 by its own weight. Other configurations are the same as those of the turbine unit 2 of FIG.
In this way, the turbine unit 2 is installed such that the main shaft 7 is inclined with respect to the horizontal plane, and the working medium 3 in the turbine unit 2 is discharged from the exhaust port 20 by its own weight, whereby the turbine impeller. Even if the working medium 3 that has passed through 5a is condensed in the turbine unit 2, the liquefied working medium 3 is easily discharged. Therefore, it is possible to prevent the liquefied working medium 3 from entering the generator 6 or coming into contact with the permanent magnets 12 and 13 and the electromagnets 14 and 15 constituting the bearing 11 to reduce the energy conversion efficiency. it can.

FIG. 9 is an enlarged cross-sectional view showing still another example of the turbine unit 2. In the example of the turbine unit 2, the turbine unit 2 in FIG. 6 is installed by tilting the main shaft 7 of the turbine unit 2 with respect to the horizontal plane so that the end on the exhaust port 20 side faces downward. 2, the working medium 3 is discharged from the exhaust port 20 by its own weight. Other configurations are the same as those of the turbine unit 2 of FIG.
Also in this case, the turbine unit 2 is installed with its main shaft 7 inclined with respect to the horizontal plane, and the working medium 3 in the turbine unit 2 is discharged from the exhaust port 20 by its own weight. It can be prevented that the liquefied working medium 3 penetrates into the portion or the liquefied working medium 3 comes into contact with the permanent magnets 12 and 13 and the electromagnets 14 and 15 to reduce the energy conversion efficiency.

  FIG. 10 shows another embodiment of the present invention. In this thermoelectric generation system, instead of the working medium circuit 4 in the embodiment of FIG. 1, the first working medium circuit 4 </ b> A that circulates the first working medium 3 </ b> A through the collector 1 and the second operation through the turbine 5. By providing the second working medium circulation path 4B for circulating the medium 3B and applying the heat amount of the first working medium 3A heated by the collector 1 to the second working medium 3B via the heat exchanger 22 The second working medium 3B is indirectly heated. The nozzle 8 and the pump 9 are provided in the second working medium circulation path 4B. Other configurations are the same as those in the first embodiment.

  Thus, by separating the working medium 3A for acquiring thermal energy from the collector 1 and the working medium 3B for driving the turbine 5, the working medium suitable for each role can be individually selected. The degree of freedom of selection can be expanded.

  In each of the above embodiments, the case of a solar thermal power generation system using solar heat as thermal energy has been described as an example, but the same effect can be achieved even when applied to a thermal power generation system using other heat sources as thermal energy. it can.

1 is a cross-sectional view showing a schematic configuration of a thermoelectric generator system according to a first embodiment of the present invention. It is an expanded sectional view of the turbine unit in the thermoelectric power generation system. It is the III-III arrow sectional drawing in FIG. It is an expanded sectional view showing other examples of a turbine unit. It is an expanded sectional view showing other examples of a turbine unit. It is an expanded sectional view showing other examples of a turbine unit. It is a VII-VII arrow sectional view in Drawing 6. It is an expanded sectional view showing other examples of a turbine unit. It is an expanded sectional view showing other examples of a turbine unit. It is sectional drawing which shows schematic structure of the thermoelectric power generation system concerning other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Collector 2 ... Turbine unit 3, 3A, 3B ... Working medium 5 ... Turbine 6 ... Generator 6A ... Generator rotor 6B ... Generator stator part 7 ... Main shaft 7a ... Thrust plate (flange part)
7aa ... Projection 8 ... Nozzle 12 ... First permanent magnet 13 ... Second permanent magnet 14, 15 ... Electromagnets 14aa, 15aa ... Projection 16 ... Sensor 21 ... Partition

Claims (14)

The working medium is heated directly or indirectly by a collector that absorbs thermal energy, the steam of the working medium is ejected from the nozzle, the turbine is rotated by the high-pressure steam from the nozzle, and the generator is generated by the rotation of the turbine. In the system for generating power by the generator stator portion provided to face the generator rotor by rotating the generator rotor in
A main shaft connecting the turbine impeller and the generator rotor is supported by a non-contact bearing, and the non-contact bearing has a structure in which a part of the main shaft is supported by an electromagnet. .   2. The repulsive force between the first permanent magnet provided on the main shaft and the second permanent magnet disposed on the fixed side opposite to the first permanent magnet and the attraction force of the electromagnet according to claim 1. A thermoelectric power generation system characterized by being supported by.   3. The thermoelectric generator system according to claim 2, wherein a repulsive force between the first permanent magnet and the second permanent magnet is applied in a radial direction orthogonal to the rotation axis of the turbine, and the axial direction is supported by the electromagnet. .   3. The axial force of the permanent magnet according to claim 2, wherein the main axis causes a force to act only in one direction in the axial direction by shifting the opposing surfaces of the first permanent magnet and the second permanent magnet. Thermoelectric power generation system with electromagnets arranged only in the direction to cancel the force.   5. The thermoelectric generation system according to claim 1, further comprising: a sensor that detects a position of the main shaft; and a unit that changes a current of the electromagnet according to a detection value of the sensor.   The thermoelectric generation system according to claim 1, wherein a flange portion is provided on the main shaft, and the electromagnet is provided opposite to the flange portion.   7. The thermoelectric generator system according to claim 1, wherein a protrusion is provided on an end surface of the main shaft facing the electromagnet to concentrate a magnetic flux from the electromagnet.   The thermoelectric generator system according to any one of claims 1 to 7, wherein the generator loader and the generator stator are the same as a facing direction of the electromagnet and the main shaft.   The thermoelectric power generation system according to any one of claims 1 to 8, further comprising a partition wall between a rotating portion and a stationary portion of the generator.   The main shaft of the unit is tilted with respect to a horizontal plane so that the working medium is discharged by its own weight from the unit including the turbine, the generator, and the main shaft. Installed thermoelectric power generation system.   11. The thermoelectric generation system according to claim 1, wherein the turbine wheel of the turbine is made of a plastic material that is not affected by the working medium.   The thermoelectric power generation system according to any one of claims 1 to 11, wherein the turbine liquefies high-pressure steam by a cooling action accompanying expansion.   13. The method according to claim 1, further comprising means for measuring the pressure of the working medium between the collector and the nozzle, the temperature of the collector, or the amount of heat input to the collector. A thermoelectric generation system provided with means for preventing current from flowing through the electromagnet when the pressure, temperature, or heat quantity to be applied falls below a predetermined threshold.   The solar thermal power generation system according to any one of claims 1 to 13, wherein the thermal energy is solar heat.

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