JPWO2008026268A1 - Generator and gas turbine power generation equipment using the same - Google Patents

Abstract

In order to provide a generator capable of reducing the thrust acting on the thrust bearing and improving the efficiency, and a gas turbine power generation facility using the generator, the stator of the generator is attached to the thrust bearing. For example, when thrust is generated in the thrust bearing due to displacement of the magnetic center between the stator and rotor of the generator, the magnetic center between the rotor and stator is set. If the stator is moved in the axial direction so that they approach each other, and thrust is generated in the thrust bearing due to the difference in thrust force between the gas turbine and the air compressor, magnetic attraction between the stator and rotor of the generator The thrust is suppressed using the force, and as a result, the thrust acting on the thrust bearing is reduced to reduce the bearing loss and suppress the decrease in efficiency.

Description

  The present invention relates to a power generator and a gas turbine power generation facility using the same, and more particularly to a power generator equipped with a thrust bearing and a gas turbine power generation facility using the same.

  In recent years, as a gas turbine power generation facility, a micro gas turbine power generation facility has become widespread by connecting a rotating portion of a gas turbine, an air compressor, and a generator on one axis or the same axis. In this kind of gas turbine power generation facility, as disclosed in, for example, Patent Document 1, the axial force with respect to the rotating shaft can be changed, for example, due to a magnetic influence or a thermal influence during operation. For example, thrust is generated, and a thrust bearing is provided at least at one location to receive this thrust, so that the rotating shaft is not easily displaced in the axial direction by the thrust.

WO 01/86130 A1

  In the gas turbine power generation facility disclosed in Patent Document 1, by providing the thrust bearing, the axial displacement of the rotation shaft can be suppressed when thrust is generated. However, the thrust acting on the thrust bearing means that a large frictional force is generated on the thrust bearing, which has been one of the factors that reduce the efficiency of the gas turbine generator facility. Furthermore, in order to reduce the frictional force, it is necessary to forcibly supply the lubricant to the thrust bearing, and it is necessary to secure a dedicated lubrication facility and lubricant supply power for this purpose, which is also a gas turbine power generation. This was a factor that reduced the efficiency of the equipment. As described above, in this type of gas turbine power generation facility, even a slight bearing loss due to friction or the like generated in the thrust bearing greatly affects the efficiency, so it is desirable not to apply a large thrust.

  An object of the present invention is to provide a generator capable of reducing the thrust acting on the thrust bearing and improving the efficiency, and a gas turbine power generation facility using the generator.

  In order to achieve the above object, the present invention is configured so that the stator of the generator can be moved in the axial direction with respect to the thrust bearing.

  Thus, by moving the stator of the generator in the axial direction with respect to the thrust bearing, for example, the thrust force is applied to the thrust bearing by the magnetic attractive force generated by the displacement of the magnetic center between the stator and the rotor. If this occurs, the stator is moved in the axial direction so that the magnetic centers of the rotor and the stator are close to each other, and the magnetic attractive force is reduced to suppress the thrust force. When thrust is generated in the thrust bearing due to the difference in the thrust force of the machine, the thrust is suppressed by pulling the rotor in the direction that reduces the thrust using the magnetic attraction between the stator and the rotor. In particular, the thrust acting on the thrust bearing is reduced to reduce the bearing loss and suppress the decrease in efficiency.

1 is a partially longitudinal side view showing a first embodiment of a gas turbine power generation facility according to the present invention. The partial longitudinal cross-sectional side view of the generator which shows 2nd Embodiment of the gas turbine power generation equipment by this invention. The control block diagram for driving a stator based on estimation of the thrust which generate | occur | produces in a thrust bearing. The partial longitudinal cross-sectional side view of the generator which shows 3rd Embodiment of the gas turbine power generation equipment by this invention. The partial longitudinal cross-sectional side view of the generator which shows 4th Embodiment of the gas turbine power generation equipment by this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Gas turbine power generation equipment, 2 ... Gas turbine, 3 ... Compressor, 4 ... Generator, 5 ... Rotary shaft, 6 ... Turbine blade, 7 ... Turbine inner casing, 8 ... Turbine outer casing, 9 ... Compression blade, 10 ... compressor casing, 11 ... support. 12 ... Ground, 13 ... Shaft collar, 14 ... Rotor, 15 ... Stator, 16 ... Rotor core, 17 ... Permanent magnet, 18 ... Holding cylinder, 19A, 19B, 24A, 24B ... End plate, 20 ... Nut, DESCRIPTION OF SYMBOLS 21 ... Stator iron core, 22 ... Stator winding, 23 ... Stator frame, 25A, 25B ... End bracket, 26 ... Bolt, 27 ... Nut, 28 ... Thrust bearing, 29 ... Radial bearing, 30 ... Inner bearing member, 31A, 31B ... Thrust member, 32 ... Radial member, 33 ... Inner radial member, 34 ... Outer radial member, 35 ... Connecting member, 36A, 36B ... Elastic body, 37A, 37B ... Damping means, 38 ... Low friction material, 39 , 47, 50 ... Position adjustment mechanism, 40 ... Screw hole, 40A ... Through hole, 41 ... Adjustment bolt, 42 ... Double nut, 43A, 43B ... Weight sensor, 44A, 44B ... Temperature sensor Sa, 45 ... processing unit, 46 ... display, 48 ... piston, 49 ... drive unit, 51 ... flexible container, 52 ... conduit, 53 ... pressing means, 54 ... solenoid valve.

  Hereinafter, a first embodiment of a gas turbine power generation facility according to the present invention will be described with reference to FIG.

  In the gas turbine power generation facility 1 according to the present embodiment, a gas turbine 2, a compressor 3, and a generator 4 are configured side by side in the axial direction around a common rotating shaft 5.

  The gas turbine 2 has a turbine blade 6 fixed on a rotary shaft 5 and a turbine inside that guides and supplies combustion gas burned by a combustor (not shown) to the turbine blade 6 and guides and discharges exhaust gas. A casing 7 and a turbine outer casing 8 are provided.

  The compressor 3 includes a compression blade 9 fixed on the rotary shaft 5 and a compressor casing 10 that supplies combustion air to the compression blade 9 and discharges the compressed combustion air.

  The turbine inner casing 7 and the turbine outer casing 8 and the compressor casing 10 are integrally connected by well-known fastening means such as bolts and nuts, and the rotating shaft 5 is horizontal by a common support base 11. Further, it is fixed to the ground 12.

  On the other hand, the generator 4 includes a rotor 14 that is in contact with the other end of the shaft collar 13 that has one end in contact with the compression blade 9, and an outer periphery of the rotor 14. And a stator 15 arranged on the side through a gap.

  The rotor 14 includes a rotor core 16 formed by laminating silicon steel plates in the axial direction, a plurality of permanent magnets 17 installed so as to form a plurality of magnetic poles in the circumferential direction on the outer periphery thereof, and these permanent magnets. A holding cylinder 18 such as a non-magnetic metal cylinder made of nickel base alloy or an insulating cylinder made of fiber reinforced plastic, which is mounted to hold 17 on the rotor core 16, and an end plate for clamping them from both sides in the axial direction 19A, 19B.

  The turbine blade 6, the compression blade 9, and the rotor 14 having the above-described configuration are connected by screwing and fastening a nut 20 to one end of the rotating shaft 5.

  The stator 15 includes a stator core 21 and a stator winding 22 attached to the stator core 21.

  The outer periphery of the stator core 21 is covered with a stator frame 23. The stator core 21 is supported so as not to rotate in the circumferential direction with respect to the stator frame 23 and supported so as to be movable in the axial direction. Has been. Both sides of the stator frame 23 are closed by end plates 24A and 24B, and end brackets 25A and 25B are positioned outside the stator frames 23. The stator frame 23, end plates 24A and 24B, end brackets The bolts 26 and nuts 27 are integrally fixed to 25A and 25B.

  A thrust bearing 28 is formed between the end plate 24A and the end bracket 25A and the shaft collar 13, and a radial bearing 29 is provided between the end plate 24B and the end bracket 25B and the outer periphery of the end plate 19B. Is formed. The thrust bearing 28 is supported by an inner bearing member 30 having an outer peripheral surface concentric with the rotary shaft 5 and a disk projecting in a direction perpendicular to the rotary shaft 5 from the outer peripheral surface, and the end plate 24A and the end bracket 25A. Thrust members 31A and 31B facing the disk surfaces on both sides of the disk formed on the inner bearing member 30 and radial members 32 supported by the end bracket 25A and facing the outer peripheral surface of the inner bearing member 30 are provided. The radial bearing 29 includes an inner radial member 33 provided on the outer peripheral surface of the end plate 19B, and an outer radial member 34 opposed to the outer peripheral surface of the inner radial member 33 and supported by the end plate 24B. ing.

  The generator 4 is cantilevered on the support base 11 by connecting the end bracket 25A and the compressor casing 10 with a connecting member 35.

  During operation of the gas turbine power generation facility 1 configured as described above, the compressor 3 sucks the combustion air as indicated by the arrow A and compresses it with the compression blades 9 and supplies the compressed combustion air to the separate regenerator as indicated by the arrow B. And heat. The compressed combustion air heated by the regenerator is introduced between the turbine inner casing 7 and the turbine outer casing 8 of the gas turbine 2 as indicated by an arrow C, and then the compressed combustion air and fuel are mixed and burned by the combustor. Then, it is supplied into the turbine inner casing 7 as indicated by the arrow D, rotates the turbine blade 6, and is exhausted as indicated by the arrow E.

  Due to the rotation of the turbine blade 6, the compressor blade 9 coaxial with the turbine blade 6 and the rotor 14 of the generator 4 also rotate. The generator 1 induces an alternating current in the stator winding 22 by the rotation of the rotor 14. The induced alternating current is, for example, once converted into a direct current by the conversion means, and then converted again into an alternating current by another conversion means and supplied to the demand side.

  In such a gas turbine power generation facility 1, for example, due to manufacturing and assembly errors of the generator 4, the magnetic center C <b> 1 in the axial direction of the rotor 14 and the magnetic center of the rotor 14 defined by the thrust bearing 28. There is a case where it is assembled in a state where C2 is deviated. In such a case, during the operation of the gas turbine power generation facility 1, an axial magnetic attractive force acts between the rotor 14 and the stator 15. The magnetic attractive force G is a magnetic attractive force acting on the rotor 14, and the magnetic attractive force H is a magnetic attractive force acting on the stator 15.

  When such magnetic attraction forces H and G are applied, the rotor 14 normally has a thrust acting in the right direction in the figure, and the force that presses the disk of the inner bearing member 30 against the thrust member 31A, that is, the thrust increases. As a result, the frictional force increases and the bearing loss increases.

  However, in the present embodiment, since the stator core 21 is configured to move in the axial direction with respect to the stator frame 23, when the magnetic attraction force is generated, the magnetic attraction force The entire stator 15 is displaced in the left direction in the figure. Due to the axial displacement of the stator 15, the magnetic attraction force between the rotor 15 and the rotor 14 is reduced, and as a result, the thrust for pressing the disk of the inner bearing member 30 against the thrust member 31 </ b> A is also reduced. Accordingly, the frictional force of the thrust bearing 28 is also reduced, so that bearing loss can be reduced and the efficiency of the generator 4 can be prevented from lowering.

  In the above embodiment, since the stator 15 is suddenly displaced by the magnetic attractive force when the generator 4 is started, the stator core 21 may collide with the end plate 14A due to its inertia. In that case, for example, elastic members 36A and 36B such as a leaf spring and a coil spring having a small spring constant are interposed between both ends in the axial direction of the stator core 21 and the end plates 24A and 24B. The collision of the stator core 21 with the end plates 24A and 24B can be prevented without hindering the axial displacement of the child 15.

  By the way, the spring constants of the elastic bodies 36A and 36B can be determined by the above-described magnetic attractive force and the deviation of the magnetic center in the axial direction of the rotor 14 and the stator 15, and can be expressed by k1 + k2 ≦ F / d. . Here, k1 is the spring constant of the elastic body 36A, k2 is the spring constant of the elastic body 36B, F is the magnetic attractive force, and d is the deviation of the magnetic center in the axial direction of the rotor 14 and the stator 15.

  FIG. 2 shows a second embodiment of the gas turbine power generation facility according to the present invention, and the same reference numerals as those in FIG.

  In the second embodiment, the first configuration different from the first embodiment is that elastic bodies 36A and 36B are interposed between the axial ends of the stator core 21 and the end plates 24A and 24B. In addition, for example, a damping container 37A, 37B such as a flexible container enclosing a fluid with high viscosity or an oil damper is interposed. By interposing the damping means 37A and 37B, it is possible to prevent the stator 15 supported on both sides by the elastic bodies 36A and 36B having a small spring constant from vibrating in the axial direction as the rotor 14 rotates. it can.

  The second configuration different from the first embodiment is that the low friction material 38 is interposed between the stator core 21 and the stator frame 23 to facilitate the axial displacement of the stator 15. It is a configuration. And as the low friction material 38, the cylindrical body which is made of fluororesin or fiber reinforced plastic and is made to contact and slides on the outer peripheral surface of the stator core 21, or a plurality of locations on the outer peripheral surface of the stator core 21 which is molded from the same material. The rail body is installed over the entire axial length of the stator frame 23, and a plurality of rail bodies are installed on the inner diameter side of the stator frame 23 at intervals in the circumferential direction.

  A third configuration different from the first embodiment is a configuration in which a position adjusting mechanism 39 that adjusts the position of the stator 15 in the axial direction is provided. The position adjustment mechanism 39 includes a screw hole 40 provided in the end plate 24B in the axial direction, an adjustment bolt 41 screwed into the screw hole 40 and connected to the stator core 21 at the tip, and protruded outside the screw hole 40. A double nut 42 screwed into the adjusting bolt 41 is used. It is possible to adjust the position by moving the stator core 21 in the axial direction by rotating the adjustment bolt 41 to the left and right, and fixing the adjustment position by screwing the double nut 42 after the position adjustment. Can do.

  By the way, as a method for adjusting the axial position of the stator 15, weight sensors 43A and 43B and temperature sensors 44A and 44B are provided on the thrust members 31A and 31B, and the output signals are shown in FIG. The thrust received by the thrust members 31A and 31B is measured, and the thrust acting on the thrust bearing 28 is estimated based on the temperature. Here, the weight sensors 43A and 43B, the temperature sensors 44A and 44B, and the arithmetic processing unit 45 constitute a thrust measuring means according to the present invention.

  Then, the thrust is displayed on the display device 46, and the operator rotates the adjusting bolt 41 and moves the stator 15 in the axial direction so that the measured value is within an appropriate range while looking at the display device 46. The position is determined and fixed with the double nut 42. Specifically, the axial position of the stator 15 is adjusted so that the calculated thrust is in the vicinity of “zero”. And it is desirable to provide three sets of the position adjusting mechanisms 39 at intervals in at least the circumferential direction so that the stator core 21 can smoothly move in the axial direction without tilting in the stator frame 23. Further, when the position adjusting mechanism 39 is provided, it is not necessary to provide the elastic bodies 36A and 36B and the damping means 37A and 37B.

  As described above, the operator manually adjusts the stator 15 with respect to the stator frame 23 in the axial direction to reduce the thrust acting on the thrust members 31A and 31B of the thrust bearing 28, thereby reducing the bearing loss. As a result, the efficiency of the generator and the gas turbine power generation facility using the generator can be improved.

  Next, a third embodiment of the gas turbine power generation facility according to the present invention will be described with reference to FIG. The same reference numerals as those in FIGS. 1 and 2 indicate the same components, and detailed description thereof will not be repeated.

  In this embodiment, the position adjusting mechanism 39 using the adjusting bolt 41 and the double nut 42 in the second embodiment is replaced with a position adjusting mechanism 47 using the piston 48 and its driving means 49. One end of the piston 48 is connected to the end of the stator core 21 through a through hole 40A provided in the end plate 24B, and the piston 48 is advanced and retracted in the axial direction by the driving means 49, so that the thrust member 31A, The position of the stator 15 in the axial direction is adjusted so that the thrust value received by 31B falls within the appropriate range. By the way, the type of the drive means 49 is not limited as long as it drives the piston 48 in the axial direction to advance and retreat, and for example, supplies and discharges fluid such as water, air, and oil. Well-known drive means such as a fluid cylinder for driving the piston 48, a magnetic drive means for magnetically driving the piston 48, and a rotary drive means for driving the piston 48 by rotating a screw can be used.

  Then, as shown in FIG. 3, the driving means 49 is driven automatically based on the weight sensors 43A and 43B and the temperature sensors 44A and 44B and the arithmetic processing unit 45 provided on the thrust members 31A and 31B. Thus, the axial position of the stator 15 can be adjusted. Specifically, as in the second embodiment, output signals from the weight sensors 43A and 43B and the temperature sensors 44A and 44B are processed by the arithmetic processing unit 45, and the thrust received by the thrust members 31A and 31B is measured. In addition, the thrust acting on the thrust bearing 28 is estimated based on the temperature. Then, a drive command is given to the drive means 49 to advance and retract the piston 48 so that the thrust value is in the vicinity of “zero”, and the axial position adjustment of the stator 15 is automatically performed.

  Furthermore, a fourth embodiment of the gas turbine power generation facility according to the present invention will be described with reference to FIG. The same reference numerals as those in FIGS. 1 to 3 indicate the same components, and thus detailed description thereof is omitted.

  In this embodiment, instead of the position adjustment mechanisms 39 and 47 according to the second and third embodiments, another position adjustment mechanism 50 is provided. The position adjusting mechanism 50 is connected across the end of the stator core 21 and the end plate 24B, and a flexible container 51 such as a diaphragm for changing the volume by supplying and discharging fluid, and the flexible For example, a conduit 52 that supplies and discharges fluid such as air, oil, and water to the permeable container 51, pressurizing means 53 that pressurizes and supplies the fluid connected to the conduit 52, And an electromagnetic valve 54 having, for example, a two-way switching function for adjusting the pressure of the fluid supplied and discharged.

  Then, the opening degree of the electromagnetic valve 54 is set to output signals from the weight sensors 43A and 43B and the temperature sensors 44A and 44B provided on the thrust members 31A and 31B, as in the second and third embodiments. The fluid is supplied to and discharged from the flexible container 51 by changing based on the above. By supplying and discharging the fluid into the flexible container 51, the stator 15 can be moved in the axial direction to adjust the position.

  Processing of output signals from the weight sensors 43A and 43B and the temperature sensors 44A and 44B is performed in the same manner as in the second and third embodiments. That is, as shown in FIG. 3, the thrust received by the thrust members 31A and 31B is measured by the arithmetic processing unit 45 based on the output signals from the weight sensors 43A and 43B and the temperature sensors 44A and 44B, and the thrust bearing 28 is changed according to the temperature. Estimate the thrust acting on. Then, a two-way switching command or an opening command is given to the electromagnetic valve 54 so that the thrust value is in the vicinity of “zero”, and fluid is supplied to or discharged from the flexible container 51. The position adjustment in the axial direction is automatically performed.

  By the way, in each said embodiment, the thrust of the thrust bearing 28 generated by the magnetic inconvenience of the generator 4 is reduced. However, when the gas turbine power generation facility 1 is viewed as a whole, thrusts of different magnitudes in different directions also work on the gas turbine 2 and the compressor 3 due to the difference in the direction and shape of the turbine blades 6 and the compression blades 9. Since the thrust acts on the thrust bearing 28 also by the difference in thrust between the gas turbine 2 and the compressor 3, the thrust acting on the thrust bearing 28 including the thrust by the gas turbine 2 and the compressor 3 is reduced. Is desirable.

  Therefore, as shown in the second to fifth embodiments, weight sensors 43A and 43B and temperature sensors 44A and 44B are provided, and the machine by the gas turbine 2 and the compressor 3 acting on the thrust bearing 28 from these measured values. The total thrust and the magnetic thrust generated by the generator 4 are measured by the arithmetic processing unit 45, and the stator 15 may be adjusted manually or automatically in the axial direction so as to reduce the total thrust. The mechanical thrust generated by the gas turbine 2 and the compressor 3 changes depending on changes in the rotational speed, the generator output, and the outside air temperature. Therefore, the position of the stator 15 is simply changed when the total thrust exceeds the allowable value. Adjustment may be made to reduce the total thrust within an allowable value, or the total thrust during the most frequent operation may be reduced by adjusting the position of the stator 15.

  As described above, according to the present embodiment, a generator capable of reducing the thrust acting on the thrust bearing and improving the efficiency, and a gas turbine power generation facility using the generator can be obtained.

  By the way, in the said embodiment, it was set as the structure which used the permanent magnet 17 as the rotor 14 of the generator 4. FIG. However, instead of using the permanent magnet 17, a rotor winding may be wound around the rotor core 16, and an excitation current may be supplied to the rotor winding.

  The present invention is essential for improving the efficiency of a generator or a gas turbine power generation facility equipped with a thrust bearing.

Claims (13)

  A rotor that is rotatably supported on both sides in the axial direction via a bearing, a stator that is disposed on the outer periphery of the rotor via a circumferential clearance, and a stator frame that supports the stator And a generator using a thrust bearing as one of the bearings, wherein the stator is supported so as to be movable in the axial direction with respect to the stator frame.   A rotor that is rotatably supported on both sides in the axial direction via a bearing, a stator that is disposed on the outer periphery of the rotor via a circumferential clearance, and a stator frame that supports the stator In a generator using a thrust bearing as one of the bearings, the stator is supported so as to be movable in the axial direction with respect to the stator frame, and the position adjustment is performed to adjust the axial position of the stator. A generator provided with a mechanism.   A rotor that is rotatably supported on both sides in the axial direction via a bearing, a stator that is disposed on the outer periphery of the rotor via a circumferential clearance, and a stator frame that supports the stator And a thrust measuring means for measuring the thrust acting on the thrust bearing while supporting the stator movably in the axial direction with respect to the stator frame in a generator using a thrust bearing as one of the bearings. And a position adjusting mechanism for adjusting the axial position of the stator based on the measurement result of the thrust measuring means.   The generator according to claim 1, wherein the stator is elastically supported in the axial direction with respect to the stator frame.   The generator according to any one of claims 1 to 3, wherein the stator is attenuated in axial movement by a damping means.   The stator according to any one of claims 1 to 3, wherein the stator is elastically supported in the axial direction with respect to the stator frame, and the movement in the axial direction is attenuated with respect to the stator frame by an attenuation means. A generator characterized by.   The generator according to claim 1, wherein the stator is supported by the stator frame via a low friction material.   A rotor that is rotatably supported on both sides in the axial direction via a bearing, a stator that is disposed on the outer periphery of the rotor via a circumferential clearance, and a stator frame that supports the stator A generator using a thrust bearing as one of the bearings, and a gas turbine power generation facility in which a rotating portion of the generator, the gas turbine, the compressor, and the generator is mounted on a common shaft. A gas turbine power generation facility characterized in that a stator is supported so as to be movable in an axial direction with respect to the stator frame.   A rotor that is rotatably supported on both sides in the axial direction via a bearing, a stator that is disposed on the outer periphery of the rotor via a circumferential clearance, and a stator frame that supports the stator A generator using a thrust bearing as one of the bearings, and a gas turbine power generation facility in which a rotating portion of the generator, the gas turbine, the compressor, and the generator is mounted on a common shaft. The stator is supported so as to be movable in the axial direction with respect to the stator frame, and a thrust measuring means for measuring a thrust acting on the thrust bearing is provided. Based on the measurement result of the thrust measuring means, the shaft of the stator is provided. A gas turbine power generation facility provided with a position adjustment mechanism for adjusting a position in a direction.   10. The gas turbine power generation facility according to claim 8, wherein the stator is elastically supported in the axial direction with respect to the stator frame. 10.     10. The gas turbine power generation facility according to claim 8, wherein the stator is attenuated in axial movement by a damping means. 11.     10. The stator according to claim 8, wherein the stator is elastically supported in the axial direction with respect to the stator frame, and the movement in the axial direction is attenuated with respect to the stator frame by attenuation means. A gas turbine power generation facility.     10. The gas turbine power generation facility according to claim 8, wherein the stator is supported by the stator frame via a low friction material. 10.

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