CN210949189U - A two-stage high-speed centrifugal air compressor for hydrogen fuel cells - Google Patents

Abstract

The utility model discloses a two-stage high-speed centrifugal air compressor for a hydrogen fuel cell, comprising a motor rotor, wherein the motor rotor comprises a motor main shaft and a magnet layer, the magnet layer is covered on the outer peripheral surface of the motor main shaft, Both ends of the main shaft of the motor are respectively provided with a low pressure impeller pull rod and a high pressure impeller pull rod, a low pressure impeller is arranged on the low pressure impeller pull rod, and a high pressure impeller is arranged on the high pressure impeller pull rod; a motor corresponding to the motor rotor a stator, the motor stator includes a stator iron core, and a stator coil is embedded in the inner inclined slot of the stator iron core; an inner casing, the inner casing is covered on the outer peripheral surface of the stator iron core; a The casing is covered on the outer peripheral surface of the inner casing. The utility model can cover the direct-drive high-speed centrifugal air compressor of the 30-100kW power level hydrogen fuel cell air system. The air compressor can meet the requirements of high pressure ratio and wide flow range, and has the advantages of high rotational speed, high efficiency and long service life. , oil-free and other advantages.

Description

A two-stage high-speed centrifugal air compressor for hydrogen fuel cells

technical field

The utility model relates to the technical field of hydrogen fuel cells, in particular to a two-stage high-speed centrifugal air compressor for hydrogen fuel cells.

Background technique

Hydrogen fuel cell is a device that directly converts the chemical energy of hydrogen and oxygen into electrical energy. Hydrogen fuel cell only produces water and heat through electrochemical reaction, which is non-polluting to the environment. The battery is quiet, with about 55dB of noise, which is about the level of a normal human conversation. The power generation efficiency of the battery can reach more than 50%, and the efficiency is high. Hydrogen fuel cells have now become a research and development hotspot, and many companies have begun to develop the hydrogen fuel cell industry, which is expected to achieve industrialization within 5-10 years.

The air compressor is one of the important components in the hydrogen fuel cell system. It lifts the oxygen in the ambient atmosphere to a certain pressure, delivers it to the hydrogen fuel cell reactor, and electrochemically reacts with the hydrogen to generate electricity and water; The driving energy comes from the hydrogen fuel cell reactor, and the air compressor and the hydrogen fuel cell reactor form an interdependent relationship, so the working characteristics of the air compressor have a significant impact on the hydrogen fuel cell.

Although air compressors are widely used in the industry, among these compressors, large compressors can provide sufficient air supply, but also have excessive volume; smaller compressors cannot provide sufficient air supply Therefore, there is still a considerable gap between the working performance of the existing industrial air compressors and the requirements for the use of on-board hydrogen fuel cells. Small-sized, lightweight air compressors for hydrogen fuel cells have become one of the important factors to enhance the practicability of on-board hydrogen fuel cells and improve the performance of hydrogen fuel cell vehicles.

In addition, the proton exchange membrane in the hydrogen fuel cell reactor needs to work under oil-free conditions, otherwise it will cause the proton exchange membrane to fail. Therefore, the compressed air that needs to be used as the oxidant cannot contain any oil components, and the existing traditional oil and gas lubricated bearings cannot meet the requirements; due to the energy relationship between the hydrogen fuel cell reactor and the air compressor, the reactor hopes to drive the air compressor with a small output electric energy, and at the same time hopes that the air compressor can provide as much compressed air as possible that meets the pressure requirements, and also It puts forward higher requirements for the working efficiency of air compressors. The existing Roots-type air compressors or twin-screw air compressors cannot meet the high-efficiency requirements; vehicle-mounted hydrogen fuel cells face the requirements of miniaturization and light weight, and air compressors The overall size is required to be as small as possible, and a high-speed air compressor is required to meet the flow and pressure ratio requirements. The rotor speed generally reaches a high-speed operation of more than 50,000 rpm, which also brings about the problem of rotor dynamics stability, and the high-speed rotor brings The heat dissipation and cooling problems also need to be comprehensively considered and solved.

Utility model content

In order to solve the problems existing in the prior art, the purpose of this utility model is to provide a direct-drive high-speed centrifugal air compressor with reasonable design and simple structure, which can cover the air system of a hydrogen fuel cell with a power level of 30-100kW. It can meet the needs of high pressure ratio and wide flow range, and has the advantages of high speed, high efficiency, long life, no oil, etc., and can meet the needs of vehicle-mounted hydrogen fuel cells.

In order to solve the above technical problems, the utility model adopts the following technical solutions to realize:

A two-stage high-speed centrifugal air compressor for a hydrogen fuel cell, characterized in that it includes

A motor rotor, the motor rotor includes a motor shaft and a magnet layer, the magnet layer is covered on the outer peripheral surface of the motor shaft, and a low-voltage impeller pull rod and a high-voltage impeller pull rod are respectively provided at both ends of the motor shaft. A low-pressure impeller is arranged on the low-pressure impeller pull rod, and a high-pressure impeller is arranged on the high-pressure impeller pull rod;

a motor stator corresponding to the motor rotor, the motor stator includes a stator iron core, and a stator coil is embedded in the inner inclined slot of the stator iron core;

an inner casing, the inner casing is covered on the outer peripheral surface of the stator iron core;

A casing, the casing covers the outer peripheral surface of the inner casing, the low-pressure side end caps and the high-pressure side end caps are respectively provided at both ends of the casing, and one end of the motor spindle passes through the low-pressure side ceramic The ball bearing is arranged on the low pressure side end cover, the other end of the motor main shaft is arranged on the high pressure side end cover through the high pressure side ceramic ball bearing, and the low pressure side end cover is provided with a low pressure worm that is covered on the low pressure impeller. A high-pressure volute covering the high-pressure impeller is arranged on the high-pressure side end cover, and the air inlet of the high-pressure volute is communicated with the air outlet of the low-pressure volute through a pipeline. There are three-phase cables and low-voltage signal connectors respectively connected with the stator coil, and motor bases are respectively provided on both sides of the lower end of the casing.

In a preferred embodiment of the present invention, the motor rotor further includes a carbon fiber protective layer, and the carbon fiber protective layer is wound on the outer peripheral surface of the magnet layer.

In a preferred embodiment of the present invention, a low-voltage side baffle and a high-voltage side baffle for magnetic isolation are respectively provided on the motor main shaft and at both ends of the magnet layer.

In a preferred embodiment of the present invention, a wave spring washer is provided on the main shaft of the motor and between the end of the high-pressure side ceramic ball bearing and the high-pressure side end cover.

In a preferred embodiment of the present invention, the high-pressure impeller is fixedly installed on the high-pressure impeller tie rod through the high-pressure impeller pre-tightening nut, and the low-pressure impeller is fixedly installed on the low-pressure impeller tie rod through the low-pressure impeller pre-tightening nut.

In a preferred embodiment of the present invention, the two-stage high-speed centrifugal air compressor for hydrogen fuel cells further includes a water cooling system, and the water cooling system includes a water inlet joint and a water outlet joint arranged on the casing, The water inlet joint is communicated with the water supply device through the water inlet pipe, the water outlet joint is communicated with the water source recovery device through the water outlet pipe, and the outer peripheral surface of the inner casing is provided with a water inlet joint and a water outlet respectively. Spiral cooling grooves connected by joints.

Compared with the prior art, the utility model adopts the above-mentioned structure to cover the direct-drive high-speed centrifugal air compressor of the hydrogen fuel cell air system with a power level of 30-100kW, and the air compressor can meet the requirements of high pressure ratio and wide flow range. , has the advantages of high speed, high efficiency, long life, and no oil, which can meet the needs of vehicle-mounted hydrogen fuel cells.

Description of drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are just some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

Figure 1 is a schematic structural diagram of the utility model.

Figure 2 is a schematic diagram of the internal structure of the utility model.

FIG. 3 is a schematic diagram of the rotor structure of the motor of the present invention.

Detailed ways

In order to make it easy to understand the technical means, creation features, achievement goals and effects realized by the present invention, the present invention will be further described below with reference to the specific figures.

Referring to Figures 1-3, a two-stage high-speed centrifugal air compressor for hydrogen fuel cells is shown in the figure, including a motor rotor, a motor stator, an inner casing 19 and a casing 20. The air compressor is controlled by The drive drives the motor rotor to rotate.

The motor rotor includes a motor main shaft 5 and a magnet layer 7, the magnet layer 7 is covered on the outer peripheral surface of the motor main shaft 5, and a low-voltage impeller tie rod 22 and a high-pressure impeller tie rod 15 are respectively provided at both ends of the motor shaft 5. There is a low pressure impeller 2 on it, and a high pressure impeller 13 on the high pressure impeller pull rod 15. In this embodiment, the motor main shaft 5 adopts a hollow structure, which can effectively reduce the weight of the rotating parts and reduce the starting torque.

The motor rotor also includes a carbon fiber protective layer 8, which is wound on the outer peripheral surface of the magnet layer 7, and the carbon fiber protective layer 8 prevents the magnet layer 7 from breaking due to centrifugal force under high-speed rotation.

A low-voltage side baffle 6 and a high-pressure side baffle 9 are respectively provided on the motor spindle 5 and at both ends of the magnet layer 7 , and the low-voltage side baffle 6 and the high-pressure side baffle 9 are mainly used for magnetic isolation.

The motor stator corresponds to the motor rotor. The motor stator includes a stator iron core 18. A stator coil 17 is embedded in the inner inclined slot of the stator iron core 18. The inner casing 19 covers the outer peripheral surface of the stator iron core 18. In this embodiment, the stator core 18 is formed by laminating silicon steel sheets.

The casing 20 is covered on the outer peripheral surface of the inner casing 19 , and the low-pressure side end caps 3 and the high-pressure side end caps 11 are respectively provided at both ends of the casing 20 , and one end of the motor spindle 5 is provided by the low-pressure side ceramic ball bearing 4 . On the low pressure side end cover 3, the other end of the motor main shaft 5 is arranged on the high pressure side end cover 11 through the high pressure side ceramic ball bearing 10, and on the low pressure side end cover 3 is a low pressure volute which is covered on the low pressure impeller 2. 1.

A wave spring washer 16 is provided on the motor main shaft 5 and located between the end of the high-pressure side ceramic ball bearing 10 and the high-pressure side end cover 11 . The wave spring washer 16 can provide an axial preload and provide sufficient force under thermal deformation conditions. the axial space.

The effective combination of the low-pressure side ceramic ball bearing 4 and the high-pressure side ceramic ball bearing 10 can prevent volatile oil and gas substances from mixing into the compressed air under the condition of normal operation of the air compressor, meeting the oil-free requirements of hydrogen fuel cells.

The low-voltage side end cover 3 serves as both one end cover of the motor and the rear end cover of the low-voltage volute 1, and the high-voltage side end cover 11 serves as both the other end cover of the motor and the rear end cover of the high-voltage volute 12. Effectively reduce the axial length of the whole machine and reduce the volume of the whole machine, which is beneficial to improve the dynamic stability of the motor rotor. The shells 12 are connected by a second clamp. The low pressure side end cover 3 and the high pressure side end cover 11 are sealed with the low pressure impeller 2 and the high pressure impeller 13 to reduce the leakage at the back of the low pressure impeller 2 and the high pressure impeller 13 .

The high-pressure side end cover 11 is provided with a high-pressure volute 12 which is covered on the high-pressure impeller 13. The air inlet of the high-pressure volute 12 is communicated with the air outlet of the low-pressure volute 1 through a pipeline. The three-phase cable 25 and the low-voltage signal connector 24 respectively connected with the stator coil 17 are respectively provided with motor bases 21 on both sides of the lower end of the casing 20 .

The outside air is inhaled by the air inlet of the low-pressure volute 1, compressed by the low-pressure impeller 2 in the first stage, and then enters the air inlet of the high-pressure volute 12 through the pipeline, and then undergoes two-stage compression through the high-pressure impeller 13 to achieve two-stage supercharging. For the purpose of using the two-stage series supercharging method, on the one hand, the pressure ratio of the air compressor is improved, on the other hand, the axial force at both ends is effectively balanced, the dynamic stability of the motor rotor is better, and the reliability of the product is improved. The air compressor is suitable for the compressed air demand of 30-100kW high-power vehicle-mounted hydrogen fuel cells.

The high pressure impeller 13 is fixedly installed on the high pressure impeller pull rod 15 through the high pressure impeller preload nut 14 , and the low pressure impeller 2 is fixedly installed on the low pressure impeller pull rod 22 through the low pressure impeller preload nut 23 .

The air compressor controls the direction of the magnetic field generated by the motor stator through the controller, thereby controlling the rotational speed of the motor rotor, adjusting the output air pressure and flow according to the external power output requirements of the fuel cell, and changing the stoichiometric ratio of the hydrogen fuel cell stack air. Improve the electrochemical reaction of hydrogen and oxygen on the membrane electrodes of hydrogen fuel cells, and improve the performance of fuel cells.

The high-power and high-speed permanent magnet motor is used to directly drive the low-pressure impeller and the high-pressure impeller to rotate at a high speed, and the maximum speed can reach 80000rpm. It avoids the use of mechanical speed-up mechanisms such as gear transmissions, reduces the volume and weight of the air compressor, and avoids the need for speed-increasing mechanisms. gear meshing vibration noise.

The two-stage high-speed centrifugal air compressor for hydrogen fuel cell also includes a water cooling system, the water cooling system includes a water inlet joint 26 and a water outlet joint 27 arranged on the casing 20, and the water inlet joint 26 is connected to the water supply through the water inlet pipe. The device is connected, the water outlet joint 27 is communicated with the water source recovery device through the water outlet pipe, and the outer peripheral surface of the inner casing 19 is provided with a spiral cooling groove respectively connected with the water inlet joint 26 and the water outlet joint 27. When the press is running, water is passed through the spiral cooling groove between the casing 20 and the inner casing 19 to dissipate heat.

To sum up, the present invention adopts the above structure and can cover the direct-drive high-speed centrifugal air compressor of the hydrogen fuel cell air system of 30-100kW power level. The air compressor can meet the requirements of high pressure ratio and wide flow range, and has high performance. It has the advantages of high speed, high efficiency, long life, and no oil, which can meet the needs of on-board hydrogen fuel cells.

The basic principles, main features and advantages of the present invention have been shown and described above. It should be understood by those skilled in the art that the present invention is not limited by the above-mentioned embodiments. The above-mentioned embodiments and descriptions only illustrate the principles of the present invention, and the present invention is not departing from the spirit and scope of the present invention. There are also various changes and improvements that fall within the scope of the claimed invention. The claimed scope of the present invention is defined by the appended claims and their equivalents.

Claims (6)

1. A two-stage high-speed centrifugal air compressor for hydrogen fuel cell comprises

The motor rotor comprises a motor main shaft and a magnet layer, wherein the magnet layer is coated on the outer peripheral surface of the motor main shaft, a low-pressure impeller pull rod and a high-pressure impeller pull rod are respectively arranged at two ends of the motor main shaft, a low-pressure impeller is arranged on the low-pressure impeller pull rod, and a high-pressure impeller is arranged on the high-pressure impeller pull rod;

the motor stator corresponds to the motor rotor and comprises a stator core, and a stator coil is embedded in an inner chute of the stator core;

the inner shell is coated on the peripheral surface of the stator core;

the motor comprises an inner shell, a motor main shaft, a low-pressure side end cover, a high-pressure side end cover, a low-pressure side ceramic ball bearing, a high-pressure side ceramic ball bearing, a low-pressure volute, a high-pressure volute, a three-phase cable and a low-pressure signal connector, wherein the outer peripheral face of the inner shell is coated with the motor main shaft, the two ends of the motor main shaft are respectively provided with the low-pressure side end cover and the high-pressure side end cover, one end of the motor main shaft is arranged on the low-pressure side end cover through the low-pressure side ceramic ball bearing, the other end of the motor main shaft is arranged on the high-pressure side end cover through the high-pressure side ceramic ball.

2. The two-stage high-speed centrifugal air compressor for the hydrogen fuel cell as claimed in claim 1, wherein: the motor rotor further comprises a carbon fiber protective layer, and the carbon fiber protective layer is wound on the outer peripheral surface of the magnet layer.

3. A two-stage high-speed centrifugal air compressor for a hydrogen fuel cell as claimed in claim 1 or 2, wherein: and a low-pressure side baffle and a high-pressure side baffle for magnetic isolation are respectively arranged on the motor spindle and at two ends of the magnet layer.

4. The two-stage high-speed centrifugal air compressor for the hydrogen fuel cell as claimed in claim 1, wherein: and a wave-shaped spring washer is arranged on the motor main shaft and between the end part of the high-pressure side ceramic ball bearing and the high-pressure side end cover.

5. The two-stage high-speed centrifugal air compressor for the hydrogen fuel cell as claimed in claim 1, wherein: the high-pressure impeller is fixedly installed on the high-pressure impeller pull rod through a high-pressure impeller pre-tightening nut, and the low-pressure impeller is fixedly installed on the low-pressure impeller pull rod through a low-pressure impeller pre-tightening nut.

6. The two-stage high-speed centrifugal air compressor for the hydrogen fuel cell as claimed in claim 1, wherein: the two-stage high-speed centrifugal air compressor for the hydrogen fuel cell further comprises a water cooling system, wherein the water cooling system comprises a water inlet connector and a water outlet connector which are arranged on the shell, the water inlet connector is communicated with a water supply device through a water inlet pipeline, the water outlet connector is communicated with a water source recovery device through a water outlet pipeline, and a spiral cooling groove which is respectively communicated with the water inlet connector and the water outlet connector is formed in the outer peripheral surface of the inner shell.

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