CN114592925A

CN114592925A - Magnetic suspension hydrogen turbine expansion device and method

Info

Publication number: CN114592925A
Application number: CN202210335795.6A
Authority: CN
Inventors: 孙耕
Original assignee: Beijing Dazhen Technology Co ltd
Current assignee: Beijing Dazhen Technology Co ltd
Priority date: 2022-03-31
Filing date: 2022-03-31
Publication date: 2022-06-07
Anticipated expiration: 2042-03-31
Also published as: CN114592925B

Abstract

The invention relates to a magnetic suspension hydrogen turbine expansion device and a method, wherein the device comprises a magnetic suspension bearing assembly and a rotor system, and the rotor system is wrapped in the magnetic suspension bearing assembly; the rotor system comprises a rotor spindle, a first driving wheel and a second driving wheel, wherein the first driving wheel and the second driving wheel are respectively arranged at two ends of the rotor spindle; the magnetic suspension bearing assembly comprises a radial bearing and an axial bearing and is used for forming bearing capacity for suspending and fixing the rotor system after being electrified. The invention reduces friction by adopting the magnetic suspension bearing, avoids polluting hydrogen driving gas, consumes shaft work by adopting the braking electronic rotor and the stator, drives the rotor system by adopting the dual-driving wheel, and has high device operation efficiency and higher energy utilization rate.

Description

Magnetic suspension hydrogen turbine expansion device and method

Technical Field

The invention belongs to the technical field of hydrogen energy application, and particularly relates to a magnetic suspension hydrogen turbine expansion device and a magnetic suspension hydrogen turbine expansion method.

Background

The hydrogen turbo-expansion device is a key part of a hydrogen liquefaction device, the device utilizes the change of the speed of the flowing working medium to carry out energy conversion, the working medium expands in the through-flow part of the turbo-expander to obtain kinetic energy, and the expansion wheel outputs work outwards, so that the internal energy and the temperature of the working medium at the outlet of the expander are reduced. Most of the existing liquid hydrogen production devices in China are based on helium refrigeration cycle, and due to the fact that physical properties of helium and physical properties of hydrogen are greatly different, the helium refrigeration cycle device has large heat exchange loss and low efficiency, and the adoption of a hydrogen turboexpander is the future development direction of the liquid hydrogen production device.

In the running process of the turboexpander, most of the prior art adopts an oil way system to provide lubrication for a bearing so as to ensure the normal running of the expander. For example, patent document CN108759146A discloses a hydrogen turbo-expansion device, which performs refrigeration by hydrogen expansion work, provides a cooling requirement of sufficient depth for hydrogen liquefaction, introduces circulating hydrogen into a turbine from a hydrogen inlet of the turbine, and performs turbo-expansion on the circulating hydrogen by working an impeller in the turbine with the circulating hydrogen, wherein a circulating oil path is used to supply lubricating oil to each bearing cycle to reduce friction.

The device can provide the cold volume that hydrogen liquefaction needs better, but the lubricating oil that the bearing lubrication adopted leaks easily and gets into the system, causes the system pollution to be difficult to handle, and lubricating oil system is complicated moreover, is unfavorable for technical development.

There are also related designs in the art that use magnetic bearings in hydrogen turboexpanders. For example, patent document CN214501885U discloses an all-low-temperature circulation hydrogen liquefier, which is based on a turbine compression and expansion technology of a magnetic suspension bearing technology, and adopts a low-temperature circulation to reduce heat leakage and power consumption, a cold compressor to replace a normal-temperature compressor, and a non-contact magnetic suspension bearing to replace a mechanical bearing and a gas bearing to realize long-time lossless operation of the bearings, thereby improving operation stability.

However, because the material for manufacturing the rotor has high requirements on mechanical strength, the materials suitable for being used as the shaft at present have the problem of hydrogen brittleness in a hydrogen environment, and most of the materials without the hydrogen brittleness problem are not suitable for being used as the shaft material, so that the hydrogen brittleness problem is easily caused when hydrogen driving gas is introduced into the device, and the service durability and the stability of the device are poor. And the mode that adopts the braking in above-mentioned scheme consumes shaft work, and energy utilization is low, and this leads to the rotor system to adopt single drive wheel to drive simultaneously, and device work efficiency is not high enough.

Therefore, how to design a magnetic suspension hydrogen turbine expansion device with high working efficiency and high energy utilization rate becomes a problem to be solved urgently by the technical personnel in the field.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a magnetic suspension hydrogen turbine expansion device and a magnetic suspension hydrogen turbine expansion method.

In a first aspect, the present invention provides a magnetic suspension hydrogen turbine expansion device, comprising a magnetic suspension bearing assembly and a rotor system, wherein the rotor system is wrapped inside the magnetic suspension bearing assembly;

the rotor system comprises a rotor spindle, a first driving wheel and a second driving wheel, wherein the first driving wheel and the second driving wheel are respectively arranged at two ends of the rotor spindle;

the magnetic suspension bearing assembly comprises a radial bearing and an axial bearing and is used for forming bearing capacity for suspending and fixing the rotor system after being electrified.

Furthermore, the rotor spindle further comprises a thrust disc coaxially arranged with the rotor spindle, the axial bearings comprise a first axial bearing and a second axial bearing which are respectively arranged on two sides of the thrust disc, a first axial coil and a second axial coil are respectively wrapped in the first axial bearing and the second axial bearing, and the first axial coil and the second axial coil are oppositely arranged;

the radial bearing comprises a first radial bearing and a second radial bearing which are respectively arranged on two sides of a rotor of the brake motor, an even number of magnetic poles which are uniformly distributed along the circumferential direction are arranged in the first radial bearing and the second radial bearing, and every two magnetic poles are used for adjusting the magnetic force of the radial bearing along one direction.

Furthermore, at least one side of the thrust disk is provided with a plurality of first dynamic pressure grooves, the surface of one side of the first radial bearing and/or the second radial bearing close to the rotor spindle is provided with a plurality of groups of second dynamic pressure grooves which are uniformly distributed along the axial direction, and each group comprises a plurality of second dynamic pressure grooves which are uniformly distributed along the circumferential direction; the first dynamic pressure groove is spiral along the axial section structure of the thrust disc, and the second dynamic pressure groove is at least one of herringbone, splayed and pi-shaped along the radial expansion structure of the rotor spindle.

Further, the device also comprises at least two protective bearings, wherein the protective bearings are arranged adjacent to the radial bearing, and the gap between the radial bearing and the rotor spindle is larger than the gap between the protective bearings and the rotor spindle.

Furthermore, the rotor spindle further comprises a first journal and a second journal, the first journal is arranged at one end of the rotor spindle close to the first driving wheel and connected with the first driving wheel, and the second journal is arranged at one end of the rotor spindle close to the second driving wheel and connected with the second driving wheel.

Further, the brake motor rotor is located between the first journal and the second journal, one end of the first journal, which is far away from the first driving wheel, is connected with the thrust disk, and the other end of the thrust disk is connected with the brake motor rotor;

the first axial bearing, the thrust disc, the second axial bearing, the first protection bearing, the first radial bearing, the brake motor stator, the second radial bearing and the second protection bearing are sequentially and coaxially arranged between the first journal and the second journal.

Further, the magnetic suspension hydrogen turbine expansion device further comprises a rotating speed monitoring assembly, wherein the rotating speed monitoring assembly comprises an electromagnetic induction tachometer and a boss or a groove arranged on the rotor system.

Furthermore, the first driving wheel and the second driving wheel are in the same mirror image shape, the hydrogen driving gas introduced into the first driving wheel and the second driving wheel has the same flow rate and state, and the first shaft neck and the second shaft neck are both in a hollow structure.

Further, a hydrogen-resistant ceramic material is adopted for the hydrogen embrittlement prevention coating treatment, the thickness of the hydrogen embrittlement prevention coating is 10-1000 nanometers, and the hydrogen embrittlement prevention ceramic material comprises aluminum oxide.

In a second aspect, the present invention also provides a magnetic suspension hydrogen turbine expansion method using the above device, including the following steps:

electrifying the magnetic suspension bearing assembly to form bearing capacity so as to suspend and fix the rotor system;

hydrogen driving gas is introduced into a first driving wheel and a second driving wheel to drive the first driving wheel and the second driving wheel to rotate so as to drive a rotor system to rotate and do work;

a brake motor rotor on the rotor spindle rotates to generate current in a brake motor stator;

the expanded hydrogen drives the gas exhaust.

Compared with the prior art, the magnetic suspension hydrogen turbine expansion device and the method provided by the invention have the following beneficial effects:

1. the magnetic bearing is adopted to reduce the friction of the hydrogen turbine device, so that the problem that lubricating oil or lubricating gas pollutes a hydrogen system is effectively avoided, the hydrogen embrittlement prevention coating treatment is carried out on the part which is easy to generate the hydrogen embrittlement problem, the hydrogen embrittlement problem generated by the device exposed in the hydrogen working environment is effectively avoided, and the durability of the device is good;

2. the brake motor stator and the rotor are arranged in the middle of the rotor spindle, so that the power generation function is realized while the continuous operation of the device is maintained, the utilization rate of the device energy is higher, the dynamic pressure groove design is adopted on the surfaces of the thrust disc and the radial bearing, and the dynamic pressure effect is utilized to provide extra bearing force for the rotor system, so that the magnetic suspension assembly can maintain the stable and efficient operation of the device under lower power, and the energy is saved;

3. the electromagnetic induction tachometer is adopted to monitor the rotating speed, and the displacement sensor is adopted to assist in adjusting the magnetic pole electromagnetic force of the radial bearing, so that the device is more accurate in adjustment and higher in working efficiency.

The foregoing describes preferred embodiments of the present invention, and is intended to provide a clear and concise description of the spirit and scope of the invention, and not to limit the same, but to include all modifications, substitutions, and alterations falling within the spirit and scope of the invention as defined by the appended claims.

Drawings

The above and other objects, features and advantages of exemplary embodiments of the present disclosure will become readily apparent from the following detailed description read in conjunction with the accompanying drawings. Several embodiments of the present disclosure are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar or corresponding parts and in which:

FIG. 1 is a schematic diagram showing the construction of a magnetic levitation hydrogen turboexpansion device according to an embodiment of the present invention;

FIG. 2 is a radial cross-sectional view showing a radial bearing of a magnetic levitation hydrogen turbine expansion device according to an embodiment of the present invention;

FIG. 3 illustrates an axial cross-sectional view of a magnetic levitation hydrogen turboexpansion apparatus according to an embodiment of the present invention;

fig. 4 is a flow diagram illustrating a magnetic levitation hydrogen turbine expansion method according to an embodiment of the present invention.

Description of reference numerals: 1-rotor system, 11-first drive wheel, 12-second drive wheel, 13-rotor spindle, 131-thrust disk, 132-first journal, 133-second journal, 134-brake motor rotor, 2-first axial bearing, 21-first axial coil, 3-second axial bearing, 31-second axial coil, 4-first radial bearing, 41-second dynamic pressure groove, 5-second radial bearing, 6-brake motor stator, 7-first protective bearing, 8-second protective bearing.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise, and "a plurality" typically includes at least two.

It is also noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such article or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in the article or device in which the element is included.

The present invention will be described in detail with reference to specific examples.

Referring to fig. 1, an embodiment of the present invention provides a magnetic suspension hydrogen turbine expansion device, including a magnetic suspension bearing assembly and a rotor system 1, where the rotor system 1 is wrapped in the bearing assembly, the rotor system 1 includes a rotor spindle 13 and a first driving wheel 11 and a second driving wheel 12 respectively disposed at two ends of the rotor spindle 13, the first driving wheel 11 and the second driving wheel 12 are driven by hydrogen driving gas, and the two driving wheels are connected in series and can bear a larger hydrogen driving gas flow. Rotor spindle 13 includes brake motor rotor 134, and brake motor rotor 134 sets up the brake motor stator 6 that cooperatees in the outside for cooperate with brake motor rotor 134 and produce the electric current, roll out the axle work in the form of electric energy.

The magnetic suspension bearing assembly comprises two radial bearings and two axial bearings and is used for forming bearing capacity of the suspension fixed rotor system 1 after being electrified.

Rotor spindle 13 still includes the thrust disc 131 of coaxial setting, and axial bearing is including establishing first axial bearing 2 and the second axial bearing 3 in thrust disc 131 both sides separately, and the parcel has first axial coil 21 and second axial coil 31 in first axial bearing 2 and the second axial bearing 3 respectively, and specifically, axial bearing includes axial bearing iron core and a plurality of axial bearing groove, and the winding has first axial coil 21 and second axial coil 31 respectively in the axial bearing groove, and first axial coil 21 sets up with second axial coil 31 relatively. A working air gap exists between the thrust disc 131 and the first axial bearing 2 and the second axial bearing 3, and the first axial bearing 2 and the second axial bearing 3 are oppositely arranged relative to the thrust disc 131 to keep the air gaps with proper sizes on the two sides. When the device is used, the thrust disc 131 and the rotor spindle 13 are fixed and integrally arranged, the device rotates together when in work, and the coils arranged in the first axial bearing 2 and the second axial bearing 3 control the electromagnetic force between the first axial bearing 2 and the second axial bearing 3 on both sides of the thrust disc 131 and the rotor spindle 13 so as to keep the balance position of the rotor in the axial direction.

Preferably, the thrust disk 131 is integrally formed with the rotor main shaft 13, and the rotor main shaft 13 is made of a high-strength and good-magnetism material, such as steel 10 and steel A3.

The radial bearing comprises a first radial bearing 4 and a second radial bearing 5 which are respectively arranged at two sides of the brake motor rotor 134, an even number of magnetic poles which are uniformly distributed along the circumferential direction are arranged in the first radial bearing 4 and the second radial bearing 5, and every two magnetic poles are used for adjusting the magnetic force in one direction.

Preferably, 8 magnetic poles are uniformly distributed in the circumferential direction in the first radial bearing 4 and the second radial bearing 5, wherein two adjacent magnetic poles are in one group and are divided into four groups, and each group is used for adjusting the magnetic force in one direction.

At least one side of the thrust disk 131 is provided with a plurality of first dynamic pressure grooves, and the surface of the first radial bearing 4 and/or the second radial bearing 5 close to the rotor side is provided with a plurality of sets of second dynamic pressure grooves 41 uniformly distributed along the axial direction, so that the rotor system 1 generates a corresponding dynamic pressure effect when rotating, so as to provide a certain bearing force for the rotor system 1. The first dynamic pressure groove has a spiral axial cross-sectional structure. Referring to fig. 2, the second dynamic pressure grooves 41 have any one of a herringbone type, and a pi type structure on the inner surface of the radial bearing, and each group includes a plurality of second dynamic pressure grooves 41 uniformly distributed in the circumferential direction.

When thrust disk 131 is provided with the first dynamic pressure groove, thrust disk 131 has a first predetermined position in the axial direction, which is not generally at the geometric center of the cross section of the two axial bearings, and which is generally shifted toward the direction of the resultant force of rotor main shaft 13, and which keeps the resultant force generated by the first dynamic pressure groove on thrust disk 131 balanced with the resultant force of rotor main shaft 13. When the thrust disc 131 of the rotor spindle 13 is in the first predetermined position, the bearing capacity required to be provided by the magnetic levitation bearing assembly is minimal, the device is relatively safe, and the electric energy resource is saved.

Similarly, when the radial bearing is provided with the second dynamic pressure groove 41, the radial bearing can control the rotor main shaft 13 to an optimal second preset position, i.e., an optimal working position. When the second dynamic pressure groove 41 is not provided, the geometric center of the axial cross section of the rotor spindle 13 coincides with the geometric center of the axial cross section of the bearing assembly, and the second preset position of the rotor spindle 13 after the second dynamic pressure groove 41 is provided is not the geometric center of the axial cross section of the bearing assembly, and is generally a slightly eccentric position. When the rotor spindle 13 works at the second preset position, the bearing capacity required to be provided by the magnetic suspension bearing assembly is the minimum, the device is safe, and the electric energy resource is saved.

In particular, for a horizontally placed device, the second preset position is generally a position that is lower and slightly off-set in the direction of rotation, under the action of gravity. Referring to fig. 3, O is the geometric center of the axial section of the radial bearing, O1 is the geometric center of the axial section of the rotor spindle 13, which shows the optimal working position of the rotor spindle 13, x is the horizontal direction, y is the vertical direction, and ω is the rotation direction of the rotor spindle 13.

The position can be obtained in advance by calculation, and parameters required by calculation include: the position and form of the second dynamic pressure groove 41, the gap between the rotor main shaft 13 and the bearing assembly, the rotational speed of the rotor main shaft 13, the weight of the rotor system 1, and the like. By controlling the electromagnetic force of the coils in the radial bearing, the rotor spindle 13 is controlled to the second preset position, and the position can also be corrected by comparing the power consumption required by the coils at each position through experiments.

Therefore, after the second dynamic pressure groove 41 is provided, the optimal working position of the rotor spindle 13 needs to be obtained, and then the magnetic force of the radial bearing is adjusted to ensure that the rotor spindle 13 rotates along the optimal working position center in the working operation state. The optimal working position of the rotor main shaft 13 is shifted from the central position of the radial bearing and the rotor main shaft 13 to a downward and eccentric rotation direction, which is the optimal working position of the second dynamic pressure groove 41, and when the rotor main shaft 13 runs at the position, the bearing force required to be provided by the magnetic levitation bearing assembly is the smallest, the safest and the electricity-saving.

Acquiring the optimal working position of the rotor spindle 13 according to the second dynamic pressure groove 41, and adjusting the magnetic force of the radial bearing to make the rotation center of the rotor spindle 13 coincide with the optimal working position, wherein the specific process comprises the following steps:

obtaining the eccentricity ratio lambda corresponding to the second dynamic pressure groove 41;

assuming a first deviation angle

Calculating a first load angle according to the eccentricity and the first deviation angle

Assuming a second deviation angle

Calculating a second load angle according to the eccentricity and the second deviation angle

Calculating according to the first load angle, the first deviation angle, the second load angle and the second deviation angle to obtain a third deviation angle

The calculation formula is as follows:

iterating the deviation angle and the load angle according to Newton iteration method for several rounds, and after each round of iteration is completed, according to eccentricity and the roundThe obtained deviation angle

Calculating to obtain corresponding load angle

Entering the next iteration till

And with

Stopping iteration when the difference value of (2) is less than 0.001 to obtain a final deviation angle, wherein a specific calculation formula is as follows:

and determining the optimal working position according to the final deviation angle and the eccentricity.

Wherein, calculate according to eccentricity and deflection angle and obtain the load angle, include:

the eccentricity lambda and the offset angle gamma₀Substituting into Reynolds equation to solve to obtain load force W in x direction and y direction_xAnd W_y；

According to load force W_xAnd W_yDetermining the load angle beta₀Wherein the load angle is calculated by the formula

The device also comprises two protective bearings, the protective bearings and the radial bearings are arranged adjacently, and the gap between the radial bearings and the rotor spindle 13 is larger than the gap between the protective bearings and the rotor spindle 13, so that the magnetic suspension bearing assembly is protected from accidental damage. When the rotor is accidentally unstable, the rotor system 1 rotating at high speed falls on the protective bearing first instead of directly on the magnetic suspension bearing assembly, so that the protective bearing bears the abrasion from the rotor system 1, and the magnetic suspension bearing assembly is protected from being damaged.

The rotor spindle 13 further includes two journals, a first journal 132 is disposed at one end of the rotor spindle 13 close to the first driving wheel 11 and connected to the first driving wheel 11, and a second journal 133 is disposed at one end of the rotor spindle 13 close to the second driving wheel 12 and connected to the second driving wheel 12.

Brake motor rotor 134 is located between first journal 132 and second journal 133, one end of first journal 132 remote from first drive wheel 11 is connected to thrust disc 131, and the other end of thrust disc 131 is connected to brake motor rotor 134; the first axial bearing 2, the thrust disk 131, the second axial bearing 3, the first protective bearing 7, the first radial bearing 4, the brake motor stator 6, the second radial bearing 5 and the second protective bearing 8 are coaxially arranged between the first journal 132 and the second journal 133 in sequence.

Preferably, the magnetic suspension hydrogen turbine expansion device further comprises a rotation speed monitoring assembly, the rotation speed monitoring assembly comprises an electromagnetic induction tachometer and a boss or a groove arranged on the rotor system 1, and the electromagnetic induction tachometer is used for acquiring the change frequency of an induction magnetic field caused by the boss or the groove so as to acquire the rotating angular speed of the rotor system 1.

Preferably, displacement sensors are arranged on the first radial bearing 4 and the second radial bearing 5 along the arrangement direction of the magnetic poles, and the displacement sensors are used for detecting the distance between the rotor system 1 and the bearing assembly and feeding back the distance to the control system to serve as reference signals for adjusting the electromagnetic force of the magnetic poles.

Preferably, the first driving wheel 11 and the second driving wheel 12 are in the same mirror image shape, and the hydrogen driving gas introduced into the first driving wheel 11 and the second driving wheel 12 has the same flow rate and state.

Preferably, the first and

second journals

132 and 133 are both hollow.

The device adopts a hydrogen-resistant ceramic material to perform hydrogen embrittlement prevention coating treatment, and the thickness of the hydrogen embrittlement prevention coating is 10-1000 nanometers.

Preferably, the hydrogen embrittlement prevention coating treatment uses alumina.

Preferably, the hydrogen embrittlement prevention coating is treated by one or more of thermal spraying, magnetron sputtering and chemical deposition.

Preferably, the parts mentioned in this embodiment are made of a material that does not generate hydrogen embrittlement as much as possible, and if a material that easily generates hydrogen embrittlement needs to be used, for example, a certain requirement is imposed on the mechanical strength of the material, the corresponding parts are subjected to coating treatment, and the material that does not generate hydrogen embrittlement is one or more of 316L stainless steel, aluminum alloy, and copper alloy.

Preferably, the drive wheel is an expansion impeller, and the first expansion impeller and the second expansion impeller are identical mirror image blade profiles.

When the rotor system works, the first axial coil 21, the second axial coil 31, the first radial bearing 4 and the second radial bearing 5 are energized to form bearing capacity for the rotor system 1 to support the rotor system 1 to suspend, so that friction is reduced, oil lubrication or gas lubrication is replaced, and pollution to hydrogen driving gas is avoided. When the rotor system 1 is suspended between the magnetic suspension bearing assemblies, two streams of high-pressure hydrogen to be expanded driving gas with the same state and flow rate are respectively led to the first driving wheel 11 and the second driving wheel 12, so that the driving wheels rotate. Because the first driving wheel 11 and the second driving wheel 12 adopt the same mirror image shape, the first driving wheel 11 and the second driving wheel 12 are mirror symmetric, and under the driving of the hydrogen driving gas with the same flow and state, the axial thrust with the same size and the opposite direction is generated in the first driving wheel 11 and the second driving wheel 12, so that the problem of axial unbalance of the whole device is avoided. The hydrogen gas drives the first driving wheel 11 and the second driving wheel 12 to rotate, so that the whole rotor system 1 is driven to rotate, the brake motor rotor 134 rotates to generate current in the brake motor stator 6, shaft work is consumed to maintain the normal operation of the magnetic suspension hydrogen turbine device, energy is recycled, a power generation function is realized, and energy waste in the hydrogen liquefaction process is avoided.

When the rotor system 1 rotates, the rotor system 1 can generate a corresponding dynamic pressure effect by the dynamic pressure groove arranged on the inner surface of the radial bearing so as to provide a certain radial bearing force for the rotor system 1; meanwhile, one side and/or the other side of the thrust disk 131 is/are provided with dynamic pressure grooves, and when the rotor system 1 rotates, the dynamic pressure grooves arranged on one side and/or the other side of the thrust disk 131 can enable the rotor system 1 to generate a corresponding dynamic pressure effect so as to provide a certain axial bearing force for the rotor system 1. With the help of the additional radial bearing force and the axial bearing force, the first axial coil 21, the second axial coil 31, the first radial bearing 4 and the second radial bearing 5 can maintain the stable and efficient operation of the device under smaller power, and energy is saved.

During operation, the whole magnetic suspension hydrogen turbine device is in a hydrogen environment, and hydrogen can be isolated by processing the hydrogen embrittlement prevention coating adopted by the rotor system 1 and the magnetic suspension bearing assembly, so that parts which are easy to generate hydrogen embrittlement problem materials are protected, and the hydrogen embrittlement problem of the parts of the device is avoided.

Referring to fig. 4, an embodiment of the present invention further provides a magnetic hydrogen turbine expansion method, which may include the following steps:

s1, energizing the magnetic suspension bearing assembly to form bearing force to suspend and fix the rotor system 1;

s2, introducing hydrogen driving gas into the first driving wheel 11 and the second driving wheel 12, and driving the first driving wheel 11 and the second driving wheel 12 to rotate so as to drive the rotor system 1 to rotate and do work;

s3, the brake motor rotor 134 on the rotor spindle 13 rotates to generate current in the brake motor stator 6;

and S4, driving a gas exhaust device by the expanded hydrogen.

According to the magnetic suspension hydrogen turbine expansion device and the magnetic suspension hydrogen turbine expansion method, the magnetic suspension bearing is adopted to reduce friction of the hydrogen turbine device, the problem that lubricating oil or lubricating gas pollutes a hydrogen system is effectively avoided, the hydrogen embrittlement prevention coating treatment is carried out on parts which are prone to hydrogen embrittlement, the hydrogen embrittlement problem of the device exposed in a hydrogen working environment is effectively avoided, and the durability of the device is good; the brake motor stator and the rotor are arranged in the middle of the rotor spindle, so that the power generation function is realized while the continuous operation of the device is maintained, the utilization rate of the device energy is higher, the dynamic pressure groove design is adopted on the surfaces of the thrust disc and the radial bearing, and the dynamic pressure effect is utilized to provide extra bearing force for the rotor system, so that the magnetic suspension assembly can maintain the stable and efficient operation of the device under lower power, and the energy is saved; the electromagnetic induction tachometer is adopted to monitor the rotating speed, and the displacement sensor is adopted to assist in adjusting the magnetic pole electromagnetic force of the radial bearing, so that the device is more accurate in adjustment and higher in working efficiency.

Claims

1. A magnetic suspension hydrogen turbine expansion device is characterized by comprising a magnetic suspension bearing assembly and a rotor system, wherein the rotor system is wrapped in the magnetic suspension bearing assembly;

2. The apparatus of claim 1, wherein the rotor spindle further comprises a thrust disk coaxially disposed therewith, the axial bearings comprise a first axial bearing and a second axial bearing respectively disposed at two sides of the thrust disk, the first axial bearing and the second axial bearing respectively enclose a first axial coil and a second axial coil, and the first axial coil and the second axial coil are disposed opposite to each other;

3. The device as claimed in claim 2, wherein at least one side of the thrust disk is provided with a plurality of first dynamic pressure grooves, and the surface of the first radial bearing and/or the second radial bearing on the side close to the rotor main shaft is provided with a plurality of sets of second dynamic pressure grooves uniformly distributed along the axial direction, each set comprising a plurality of second dynamic pressure grooves uniformly distributed along the circumferential direction; the first dynamic pressure groove is spiral along the axial section structure of the thrust disc, and the second dynamic pressure groove is at least one of herringbone, splayed and pi-shaped along the radial expansion structure of the rotor spindle.

4. The apparatus of claim 2, further comprising at least two protective bearings disposed adjacent to the radial bearing, the radial bearing having a greater clearance from the rotor shaft than the protective bearings.

5. The apparatus of claim 4, wherein the rotor shaft further comprises a first journal disposed at an end of the rotor shaft proximate the first drive wheel and coupled to the first drive wheel, and a second journal disposed at an end of the rotor shaft proximate the second drive wheel and coupled to the second drive wheel.

6. The apparatus of claim 5, wherein the brake motor rotor is located between the first journal and the second journal, the end of the first journal remote from the first drive wheel being connected to the thrust plate, the other end of the thrust plate being connected to the brake motor rotor;

7. The apparatus of claim 2, wherein the magnetic levitation hydrogen turbo-expansion device further comprises a rotational speed monitoring assembly, the rotational speed monitoring assembly comprising an electromagnetic induction tachometer and a boss or a groove disposed on the rotor system;

and displacement sensors are arranged on the first radial bearing and the second radial bearing along the arrangement direction of the magnetic poles.

8. The apparatus of claim 5, wherein the first drive wheel and the second drive wheel are identical mirror images, the hydrogen drive gas to the first drive wheel and the second drive wheel has the same flow rate and state, and the first journal and the second journal are both hollow.

9. The device according to claim 1, wherein the device comprises a hydrogen embrittlement prevention coating formed after coating treatment, the thickness of the hydrogen embrittlement prevention coating is 10-1000 nm, and the material of the hydrogen embrittlement prevention coating is alumina.

10. A magnetic levitation hydrogen turbine expansion method using the apparatus of any of claims 1-9, comprising the steps of:

hydrogen driving gas is introduced into a first driving wheel and a second driving wheel to drive the first driving wheel and the second driving wheel to rotate so as to drive a rotor system to rotate and apply work;

a brake motor rotor on the rotor spindle rotates to generate current in the brake motor stator;

the expanded hydrogen drives the gas exhaust.