CN110863910A

CN110863910A - Long-span rotor system and gas turbine generator set

Info

Publication number: CN110863910A
Application number: CN201911370769.1A
Authority: CN
Inventors: 靳普; 刘慕华
Original assignee: Xunling Tengfeng Automotive Power Technology (beijing) Co Ltd
Current assignee: Yongxu Tengfeng New Energy Power Technology Beijing Co ltd; Zhiyue Tengfeng Technology Group Co ltd
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2020-03-06

Abstract

The invention provides a long-span rotor system and a gas turbine generator set, wherein the rotor system comprises a rotating shaft, and the rotating shaft is of an integrally formed structure; the rotating shaft is sequentially provided with a thrust bearing, a first radial bearing, a motor, a gas compressor, a second radial bearing and a turbine. In the rotor system, two supporting points (namely a first radial bearing and a second radial bearing) are respectively arranged at two ends of the rotating shaft, so that the balance of the rotating shaft is better, and the running stability of the rotor system is good; the size limitation of the tail part of the rotating shaft can be solved, and the problems of unstable operation and serious vibration of a rotor system are solved.

Description

Long-span rotor system and gas turbine generator set

Technical Field

The invention relates to the technical field of rotor dynamics, in particular to a long-span rotor system and a gas turbine generator set.

Background

In the field of micro gas turbine power generation, a micro gas turbine power generator set generally includes a coaxially mounted generator and a micro gas turbine. Specifically, the micro gas turbine mainly comprises three parts, namely a compressor, a combustion chamber and a turbine. The air is compressed into high-temperature and high-pressure air after entering the air compressor, then the high-temperature and high-pressure air is supplied to the combustion chamber to be mixed and combusted with fuel, the generated high-temperature and high-pressure gas expands in the turbine to do work, the turbine is pushed to rotate, and the generator is driven to generate electricity. Because the magnetic components and coil windings in the generator are not resistant to high temperature, the generator cannot be installed at the hot end of the rotor system, namely, at the turbine side.

In the prior art, a generator is generally installed at an air inlet end of a rotating shaft of a micro gas turbine, namely an air inlet end of a compressor. To support the rotating shaft, radial bearings are provided between the rotating shaft and the stator at both ends of the stator as fulcrums. The tail part (namely the air outlet end) of the gas turbine is also provided with components such as a gas compressor, a turbine, a combustion chamber and the like, so that the weight is larger, the tail part of a rotating shaft cannot be too long, otherwise, the problems of downward inclination of the tail part, upward warping of the head part, unstable operation of a rotor, serious vibration and the like can be caused.

Meanwhile, the conventional convex thrust disc is integrally manufactured with the rotating shaft, so that the whole shaft material needs to be turned during machining, the height of the thrust disc is large, large turning amount can be generated, materials are wasted, and the turning times are large, so that stress removal is required for many times, and the process is complex. In addition, because a single thrust disc is heavy in weight, when the rotating shaft rotates at a high speed, inertia force can be generated, the rotating shaft is caused to deviate from the axis to rotate, and the rotating stability is poor and the vibration is serious in a rotor system.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide a long-span rotor system and a gas turbine generator set, wherein two branch points are respectively arranged at two ends of a rotating shaft, so that the rotating shaft has better balance and the rotor system has good running stability; meanwhile, the invention can solve the size limitation of the tail part of the rotating shaft, solve the problems of unstable operation and serious vibration of a rotor system and solve the technical problems of complex structure and easy damage of the existing integrated thrust bearing.

The technical scheme of the invention is as follows:

according to an aspect of the present invention, there is provided a long span rotor system comprising:

a long span rotor system, comprising:

the rotating shaft is of an integrally formed structure;

the rotating shaft is sequentially provided with a thrust bearing, a first radial bearing, a motor, a gas compressor, a second radial bearing and a turbine.

Further, the first radial bearing and the second radial bearing are both air bearings, and the air bearings are any one of dynamic pressure bearings, static pressure bearings or dynamic and static pressure hybrid bearings.

Further, the thrust bearing and the first radial bearing are integrated bearings.

Furthermore, a reinforcing ring is arranged between the compressor and the turbine, and the second radial bearing is sleeved on the reinforcing ring.

Furthermore, a supporting part is arranged in the middle of the inner wall of the reinforcing ring and is abutted against the rotating shaft, and the inner wall of the reinforcing ring is positioned on two sides of the supporting part and is arched;

or the reinforcing ring comprises a cylindrical barrel and a radial limiting ring arranged on the outer side of the barrel wall, two ends of the cylindrical barrel are embedded into grooves of the end faces of the compressor and the turbine, and the radial limiting ring is clamped on the end face of the compressor or the turbine;

or, the reinforcing ring and the compressor or the turbine are integrally formed.

Furthermore, a first air inlet channel is arranged on the thrust bearing and the motor, and the first air inlet channel on the thrust bearing and the motor is oppositely arranged and communicated with the air inlet of the air compressor;

and a second air inlet channel is arranged between the motor stator of the motor and the motor shell, and the second air inlet channel is communicated with the air inlet of the air compressor.

Furthermore, one end of the rotating shaft, which is provided with the motor, is provided with two thrust discs, the two thrust discs are oppositely arranged and form an annular groove together with the rotating shaft, and the thrust bearing is arranged in the annular groove;

the thrust bearing is an air bearing and comprises two bearing units which are arranged oppositely, an annular air cavity is arranged between the two bearing units and is communicated with an air inlet on the thrust bearing shell.

Furthermore, of the two thrust disks, the thrust disk close to the shaft end is arranged in a detachable structure;

or the two thrust discs and the rotating shaft are integrally formed, and the thrust bearing is a bearing which can be separated along a radial surface.

According to another aspect of the present invention, there is provided a gas turbine power plant comprising: the rotor system comprises a motor casing, a gas turbine casing, a combustion chamber and the rotor system;

the gas turbine engine comprises a motor, a gas turbine, a gas compressor, a gas turbine, a motor casing, a gas turbine, a gas compressor, a gas turbine;

the combustion chamber is connected with the gas turbine casing, the air inlet of the combustion chamber is connected with the air outlet of the air compressor, and the air outlet of the combustion chamber is connected with the air inlet of the turbine.

Furthermore, a diffuser is arranged between the exhaust port of the air compressor and the air inlet of the combustion chamber.

Compared with the prior art, the invention has the following beneficial effects:

1. in the rotor system, two supporting points (namely a first radial bearing and a second radial bearing) are respectively arranged at two ends of the rotating shaft, so that the balance of the rotating shaft is better, and the running stability of the rotor system is good; the size limitation of the tail part of the rotating shaft can be solved, and the problems of unstable operation and serious vibration of a rotor system are solved.

2. In the rotor system, the thrust bearing and the first radial bearing adopt the integrated gas bearing, the integrated gas bearing can simultaneously realize radial and axial support on the rotating shaft, the processing technology is simple and easy to operate, the processing precision is high, the precision of combined assembly does not need to be considered in the assembly process, the manufacturing cost is low, and the practicability is high.

3. The air inlet mode and the air inlet channel position of the rotor system are arranged, so that air inlet of the air compressor is sufficient, heat dissipation of the motor is facilitated, the axial size adjustable range of the whole rotor system is large, and the dynamic characteristic of the rotor system is good.

4. In the thrust bearing structure, the thrust discs on two sides of the annular groove are low in height, the turning amount is small during processing, the material consumption is low, the process is relatively simple, the mass distribution is relatively uniform, and the stability is better when the rotating shaft rotates in height.

5. The gas turbine generator set using the rotor system has low requirements on processing precision and assembly precision, is low in cost and is suitable for engineering batch production; meanwhile, the gas turbine generator set of the invention has sufficient air intake; because the two fulcrums (namely the first radial bearing and the second radial bearing) are respectively positioned at the two ends of the rotating shaft, the size adjustable range of the rotating shaft in the axial direction is larger, the stress of the rotating shaft is uniform, and the running stability of the gas turbine generator set is good.

Drawings

Fig. 1 is a schematic structural diagram of a rotor system and a gas turbine generator set according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a portion of the invention at position A in FIG. 1.

FIG. 3 is a partial enlarged view of the position B in FIG. 1 according to the present invention.

Fig. 4 is a schematic structural diagram of a rotor system and a gas turbine generator set according to a second embodiment of the invention.

Fig. 5 is a partial enlarged view of the position C of fig. 4 according to the present invention.

Fig. 6 is a partial enlarged view of the position D in fig. 4 according to the present invention.

Detailed Description

In order to better understand the technical scheme of the invention, the invention is further explained by combining the specific embodiment and the attached drawings of the specification.

According to one aspect of the present invention, a long span rotor system is provided.

Example one

As shown in fig. 1, the shaft 100 includes a first shaft segment 110 and a second shaft segment 120, which are integrally formed, wherein the diameter of the first shaft segment 110 is greater than that of the second shaft segment 120, and a step surface 130 is formed at the transition between the first shaft segment 110 and the second shaft segment 120;

the thrust bearing 200, the first radial bearing 900 and the motor 300 are sequentially arranged on the first shaft section 110, the compressor 500, the second radial bearing 400 and the turbine 600 are sequentially arranged on the second shaft section 120, and one end of the compressor 500 is abutted to the step surface 130.

In the rotor system of the present invention, the rotating shaft 100 is supported by the bearings (the first radial bearing 900 and the second radial bearing 400) at both ends, so that the stress is uniform, and the weight imbalance caused by the suspension of the rotor shaft end can be avoided.

Preferably, the first radial bearing 900 and the second radial bearing 400 are air bearings, and may be dynamic pressure bearings, static pressure bearings, or hybrid dynamic and static pressure bearings.

Preferably, the thrust bearing 200 and the motor 300 are provided with a first air inlet passage P1. The first air inlet channel of the thrust bearing 200 is opposite to the first air inlet channel P1 of the motor 300 and is communicated with the air inlet of the compressor 500. This allows the inlet air to the compressor 500 to be more unobstructed and the inlet air to the compressor 500 to cool the stator windings of the motor 300.

Preferably, a second air inlet duct P2 may be provided between the motor stator and the motor housing of the motor 300. In the case of a large intake demand, the two intake ports (i.e., the first intake port P1 and the second intake port P2) may be simultaneously charged. Thus, sufficient air intake of the compressor 500 can be met, and the air intake of the compressor 500 can further cool the shell of the motor, the stator of the motor and the stator winding.

Since the weight of the rotating shaft 100 is better as the weight is lighter in the rotor system and the weight is lighter as the diameter of the rotating shaft 100 is smaller, the strength of the rotating shaft 100 is required again during the high-speed rotation of the rotor system. In order to take the rotor dynamics and the strength of the rotating shaft 100 into consideration, the shaft diameter of the second shaft section 120 may be designed to be thin, and a reinforcing ring 700 may be fixedly installed between the compressor 500 and the turbine 600, as shown in fig. 3, to meet the rotor stiffness requirement, and the reinforcing ring 700 may serve as the installation shaft of the second radial bearing 400. The second radial bearing 400 is sleeved on the reinforcing ring 700; the second radial bearing 400 is provided with an annular air chamber which is supplied by an air inlet on the gas turbine stator.

Through the layout of the rotor system and the arrangement of the air inlet channels on the thrust bearing 200 and the motor 300, the rotor system disclosed by the invention is compact and simple in structure; and the installation of bearing and motor can not block the air admission of compressor 500, and the axial dimension adjustable range of rotor system is big simultaneously, and two support points set up at the axle head, and the operation stationarity of rotor system is good.

Preferably, the thrust bearing 200 is an integrated air bearing that provides both radial and axial support.

Specifically, two coaxial thrust disks are disposed near the inlet end of the first shaft segment 110, and an annular groove 140 coaxial with the rotating shaft is formed between the two opposite thrust disks and the rotor shaft wall. The thrust bearing 200 is disposed in the annular groove 140, and the thrust bearing 200 includes left and right bearing units disposed opposite to each other, and an air chamber is disposed between the two bearing units. Specifically, an annular air cavity is formed in the end face of one of the bearing units, an air inlet on the bearing shell is continuously ventilated, the air enters the annular air cavity of the bearing along a gap between the two bearing units, the two bearing units are respectively pushed to the thrust disc towards two sides, and an axial thrust effect is achieved. Referring to fig. 2, the gas introduced into the thrust bearing 200 flows out from the bottom of the bearing to the left and right sides, flows through the left thrust disk edge and flows out through the end cover, and flows into the gas cavity of the motor 300 from the pressure reducing hole 310 to be merged into the gas introduced into the first gas inlet P1.

In order to meet the assembly requirement of the thrust bearing 200, the thrust disc near the shaft end can be arranged in a detachable manner, so that the thrust bearing 200 can enter the annular groove 140; or, two thrust discs are integrally formed with the rotating shaft 100, and the thrust bearing 200 is a bearing separable along a radial surface and is sleeved on the shaft wall in the annular groove 140 in a fastening and fixing manner.

In the axial thrust structure, the thrust discs on two sides of the annular groove 140 are low in height, the turning amount is small during processing, the material consumption is low, the process is relatively simple, the mass distribution is relatively uniform, and the stability is better when the rotating shaft rotates in height.

The long-span rotor system of the present invention can be applied to generator sets with or without a regenerator.

According to another aspect of the present invention, the present invention also provides a gas turbine power generator unit using the rotor system described above, the power generator unit comprising:

the rotor system, motor case 810, gas turbine case 820, and combustor 830 described above; the motor case 810 covers the outer periphery of the motor 300, the gas turbine case 820 covers the outer peripheries of the compressor 500 and the turbine 600, and is connected to the motor case 810, the combustion chamber 830 is connected to the gas turbine case 820, an air inlet of the combustion chamber 830 is connected to an air outlet of the compressor 500, and an air outlet of the combustion chamber 830 is connected to an air inlet of the turbine 600.

Preferably, a diffuser 840 is disposed between an exhaust port of the compressor 500 and an intake port of the combustion chamber 830 to further increase the pressure of the high-temperature and high-pressure gas entering the turbine 600 to perform work.

In the gas turbine generator set, all the bearings are arranged in the motor casing 810, so that only the machining precision of the part for arranging the bearing stator in the casing is required to be ensured, and the part for connecting the bearing stator in the casing can be machined through one-time clamping during assembly. Meanwhile, the gas turbine generator set of the invention has sufficient air intake; because the two fulcrums (i.e. the first radial bearing 900 and the second radial bearing 400) are respectively positioned at the two ends of the rotating shaft 100, the size adjustable range of the rotating shaft 100 in the axial direction is larger, the stress of the rotating shaft is uniform, and the running stability of the gas turbine generator set is good.

Example two

The first radial bearing 900 and the thrust bearing 200 in the first embodiment may be provided as an integral bearing, and the thrust disk may be provided as one. The integrated bearing is an integrated air bearing, and has a radial supporting function and an axial supporting function.

As shown in fig. 4 and 5, the integrated bearing of the present embodiment includes: the thrust disc comprises a first bearing body, a thrust disc and a second bearing body; the thrust disc is fixedly connected with the rotating shaft 100 or integrally formed; the first bearing body and the second bearing body are sleeved on the rotating shaft and positioned on two sides of the thrust disc; the first bearing body has a radial bearing portion and a thrust bearing portion which are integrally formed, the radial bearing portion has a predetermined radial clearance with the rotating shaft 100 in the radial direction, and the thrust bearing portion is installed opposite to the thrust disk in the axial direction and has a predetermined first axial clearance; the second bearing body is mounted axially opposite the thrust disc with a predetermined second axial clearance. The integral type bearing of this embodiment still includes bearing housing and bearing cap, and the periphery of first bearing body, thrust disc and second bearing body is located to the bearing housing cover, and the bearing cap is installed in the one end of the second bearing body of pivot, fixed second bearing body in the axial to with bearing housing transition fit.

Specifically, the integrated bearing of the present embodiment may be any one of a static pressure gas bearing, a dynamic pressure gas bearing, or a hybrid dynamic and static pressure gas bearing.

When the integral type bearing of this embodiment sets up to static pressure gas bearing, be provided with first annular air cavity between the periphery of the radial bearing portion of first bearing body and the bearing housing, the bottom of first annular air cavity is provided with the first through-hole that link up first annular air cavity and radial clearance, be provided with second annular air cavity between the thrust bearing portion of first bearing body and the bearing housing, the bottom of second annular air cavity is provided with the second through-hole that link up second annular air cavity and first axial clearance, be provided with third annular air cavity between second bearing body and the bearing end cover, the bottom of third annular air cavity is provided with the third through-hole that link up third annular air cavity and second axial clearance. Meanwhile, a first air inlet and a second air inlet which are used for communicating the first annular air cavity and the second annular air cavity with an external air source are also arranged on the bearing shell, and a third air inlet which is used for communicating the third annular air cavity with the external air source is arranged on the bearing end cover.

When the integrated bearing of the present embodiment is provided as a dynamic pressure bearing, a dynamic pressure generating groove is provided on an inner diameter surface of the radial bearing portion of the first bearing body or a portion of the rotating shaft where the radial bearing portion is mounted; a dynamic pressure generating groove is formed in an end surface of the thrust bearing portion of the first bearing body facing the thrust disc or an end surface of the thrust disc facing the thrust bearing portion; a dynamic pressure generating groove is provided in an end surface of the second bearing body facing the thrust disk or an end surface of the thrust disk facing the second bearing body.

When the integrated bearing of the present embodiment is provided as a hybrid bearing of dynamic and static pressures, it has both the features of the hydrostatic bearing and the dynamic pressure bearing.

In this embodiment, the first bearing body has both the radial bearing portion and the thrust bearing portion, so that the perpendicularity between the axial direction and the action surface of the thrust bearing portion is ensured by machining the thrust bearing portion with the axial direction as a reference, or the perpendicularity between the action surface of the thrust bearing portion and the axial direction is ensured by machining the inner diameter of the radial bearing portion with the action surface of the thrust bearing portion as a reference in the machining process. The processing technology is simple and easy to operate, the processing precision is high, meanwhile, the precision of combined assembly is not required to be considered in the assembly process, and the assembly technology is simple.

In various embodiments of the invention:

further, referring to fig. 6, a support portion is disposed in the middle of the inner wall of the reinforcement ring 700 and abuts against the rotation shaft 100, and the inner wall of the reinforcement ring 700 is located at two sides of the support portion and is arched to meet the stress requirement.

Further, referring to fig. 3, the reinforcing ring 700 includes a cylindrical barrel having both ends inserted into the grooves of the end surfaces of the compressor 500 and the turbine 600, and a radial retaining ring disposed outside the barrel wall to retain the end surface of the compressor 500 or the turbine 600.

Further, a reinforcing ring is integrally formed with the compressor 500 or the turbine 600.

The above description is only a preferred embodiment of the application and is illustrative of the principles of the technology employed. It will be appreciated by a person skilled in the art that the scope of the invention as referred to in the present application is not limited to the embodiments with a specific combination of the above-mentioned features, but also covers other embodiments with any combination of the above-mentioned features or their equivalents without departing from the inventive concept. For example, the features described above have similar functions to (but are not limited to) those disclosed in this application.

Claims

1. A long span rotor system, comprising:

the rotating shaft is of an integrally formed structure;

2. The long span rotor system of claim 1, wherein the first and second radial bearings are each air bearings, and wherein the air bearings are any one of dynamic pressure bearings, static pressure bearings, or hybrid dynamic and static pressure bearings.

3. The long-span rotor system of claim 1, wherein the thrust bearing and the first radial bearing are a unitary bearing.

4. The long-span rotor system of claim 1, wherein a reinforcing ring is disposed between the compressor and the turbine, and the second radial bearing is sleeved on the reinforcing ring.

5. The long-span rotor system of claim 4, wherein a support portion is disposed at the middle of the inner wall of the stiffener ring and abuts against the rotating shaft, and the inner wall of the stiffener ring is arched at two sides of the support portion;

6. The long-span rotor system of claim 1, wherein the thrust bearing and the motor are provided with a first air inlet channel, and the thrust bearing and the first air inlet channel of the motor are arranged oppositely and communicated with an air inlet of the compressor;

7. The long-span rotor system of claim 1, wherein the end of the rotating shaft where the motor is arranged is provided with two thrust discs, the two thrust discs are oppositely arranged and form an annular groove together with the rotating shaft, and the thrust bearing is arranged in the annular groove;

8. The long-span rotor system of claim 7, wherein one of the two thrust disks near the axial end is detachably disposed;

9. A gas turbine power generation assembly, comprising: an electric machine case, a gas turbine case, a combustion chamber and a rotor system according to any one of claims 1 to 8;

10. The gas turbine power plant of claim 9, wherein a diffuser is disposed between the compressor discharge and the combustor inlet.