CN116398452B

CN116398452B - A magnetic levitation centrifugal heat pump compressor with wide-range variable frequency operation

Info

Publication number: CN116398452B
Application number: CN202310411408.7A
Authority: CN
Inventors: 钟仁志; 袁军; 陈光任
Original assignee: Xinlei Compressor Co Ltd
Current assignee: Xinlei Compressor Co Ltd
Priority date: 2023-04-13
Filing date: 2023-04-13
Publication date: 2026-03-31
Anticipated expiration: 2043-04-13
Also published as: CN116398452A

Abstract

This invention relates to the field of centrifugal compressors, and more particularly to a magnetically levitated centrifugal heat pump compressor with wide-range variable frequency operation. The compressor has a cooling channel, which includes a motor cooling channel, a deflection channel, and a discharge channel, all sequentially connected. When refrigerant flows in from the motor cooling channel, then through the deflection and discharge channels, and finally out from the suction port, it mixes with the low-temperature, low-pressure refrigerant gas in the first intake port to form superheated vapor. This hot vapor then enters the gas circulation structure through the first intake port, actively participating in the compressor's circulation process. By connecting the cooling channel to the compressor's gas circulation structure, this compressor achieves a more compact structure, reduces the need for external circuit switching, and lowers costs.

Description

Magnetic suspension centrifugal heat pump compressor with wide frequency conversion operation

Technical Field

The invention relates to the field of centrifugal compressors, in particular to a magnetic suspension centrifugal heat pump compressor operated in a wide frequency conversion mode.

Background

The centrifugal compressor is composed of a rotor, a stator, a bearing and the like. Parts such as impellers are sleeved on the main shaft to form a rotor, and the rotor is supported on a bearing and driven by a power machine to rotate at a high speed. The stator comprises a shell, a partition plate, a seal, an air inlet chamber, a volute chamber and the like. The fixing elements such as a diffuser, a bend, a reflux device and the like are formed between the partition plates. Centrifugal compressors having only one impeller are known as single stage centrifugal compressors, and those having more than two impellers are known as multistage centrifugal compressors. The stage consists of channels such as impellers and diffusers behind them. The impeller is a key component of the centrifugal compressor, and has three types of closed type, semi-open type and open type. The open impeller has no shroud and wheel disc, and the impeller is on the shaft. When the impeller rotates at high speed, gas is sucked from the center of the impeller due to the interaction of the force between the blades and the gas, mainly the centrifugal force, and flows along the blade path (the passage between the blades) to the outer edge of the impeller. The impeller works on the gas, the gas obtains energy, and the pressure and the speed are improved. The gas then flows through a diffuser or the like, where the velocity is reduced and the pressure is further increased, i.e. the kinetic energy is converted into pressure energy. The gas flowing out from the diffuser enters the volute to be conveyed out, or enters the next stage to be compressed continuously through a bend and a reflux device.

At present, the centrifugal compressor gradually adopts oil-free technology to replace the original oil way lubrication, thereby eliminating a lubricating oil system. However, the existing centrifugal compressors have a narrower operating range, basically can only meet the working condition requirements of cold water of an air conditioner, but can meet the working condition requirements of large pressure ratio such as heat pumps, air-cooled cold water, ice cold storage and the like, which are mostly gear-accelerating centrifugal compressors of oil-containing systems, the compressors are driven by asynchronous motors and are increased in rotating speed by gear pairs, the centrifugal compressors have certain transmission loss, the overall efficiency is lower, bearings are mostly oil-lubricated bearings, the oil lubrication system is required, the system is complex, the reliability is reduced, most of motor cooling is that refrigerant gas or liquid enters the motor housing to cool the motor, and then is directly discharged from an air return port of the motor housing to return to the evaporator, so that the internal structure is not particularly compact, external connection and path changing are required to be added, the cost is high, the heat exchange capacity of the evaporator is reduced to a certain extent, the system performance is reduced, and the like.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide the magnetic suspension centrifugal heat pump compressor with wide frequency conversion operation, which is characterized in that a more reasonable pneumatic design technology and a permanent magnet frequency conversion technology are utilized to perform optimization integration, so that the maximum operation pressure ratio and the operation range of the compressor are improved, the compressor can be operated under heat pump working conditions, air cooling cold water working conditions, industrial cold water working conditions, ice cold storage working conditions and the like, the air conditioning cold water working conditions can be considered, the oil-free operation of the system is realized by adopting a magnetic suspension bearing technology, the refrigerant gas cooled by a motor is communicated with an air inlet chamber of the compressor through an ingenious cooling channel design, the structure of the compressor is more compact, the pipeline connection with an external connection system is reduced, the cost is reduced, and the overall efficiency is improved to a certain extent.

In order to achieve the above purpose, the present invention adopts the following technical scheme:

The magnetic suspension centrifugal heat pump compressor capable of wide frequency conversion operation comprises a shell, a gas circulation structure and a motor assembly, wherein the gas circulation structure and the motor assembly are arranged in the shell, the shell comprises a gas suction shell, a first-stage volute, a motor shell and a second-stage volute, the second-stage volute and the first-stage volute are respectively and fixedly connected to the left end and the right end of the motor shell, and the gas suction shell is fixedly arranged at the right end of the first-stage volute;

The compressor is internally provided with a cooling channel, the cooling channel comprises a motor cooling channel, a steering channel and a discharge channel, and the motor cooling channel, the steering channel and the discharge channel are sequentially communicated; the motor cooling channel comprises a liquid supply inlet, a spiral groove and a liquid supply outlet, wherein the liquid supply inlet, the spiral groove and the liquid supply outlet are all arranged in the middle of the motor shell, the spiral groove is arranged around the outer ring of the stator, and the liquid supply inlet which is longitudinally arranged and the liquid supply outlet which is transversely arranged are respectively communicated with the two ends of the spiral groove; the steering channel comprises a first channel, a first cavity and a second channel which are sequentially connected, the first cavity is arranged between the second bearing and the motor shell, the second channel is axially arranged in the second bearing, the first channel is arranged on the outer diameter of the second bearing and axially penetrates through the second bearing, the right end of the first channel is communicated with the left end of the liquid supply outlet, the discharging channel comprises a rotor air gap, a third channel, a volute channel I and an air suction channel which are sequentially connected, the rotor air gap is arranged between the stator and the main shaft, the third channel is axially arranged in the first bearing, the volute channel I is arranged in the first volute, the air suction channel is arranged on the air suction shell, the rotor air gap is communicated with the second channel, the air suction channel is connected with a first air inlet of the compressor, the refrigerant is mixed with low-temperature low-pressure refrigerant gas in the first air inlet after flowing through the cooling channel, and can form superheated steam, and the hot steam enters the inside the compressor through the first air inlet, so that the part of the refrigerant carries heat after passing through the cooling motor and actively participates in the circulation process of the compressor.

Preferably, the gas circulation structure further comprises a gas suction assembly, a gas discharge assembly and a gas transmission channel;

The air suction assembly comprises a first impeller and a first-stage diffuser, wherein the first impeller is arranged in a first air inlet, one surface with larger surface area is fixedly connected to the right end of a main shaft through a bolt, and the first-stage diffuser is clamped between a first bearing and the first impeller and inserted on the outer diameter of the right end of the main shaft;

The exhaust assembly comprises a second impeller and a second diffuser, the second impeller is arranged in a second-stage volute, one surface with larger surface area is fixedly connected to the left end of the main shaft through a bolt, the second diffuser is clamped between the second impeller and is inserted on the outer diameter of the left end of the main shaft, the second volute is provided with a second air outlet which passes through the second diffuser and is communicated with the second impeller, and the second air outlet is communicated to the outer surface of the second volute;

The second impeller is arranged in the second air inlet, and the other end of the gas transmission channel is connected with the second air inlet.

Preferably, the first air inlet is further internally provided with an adjustable guide vane, and the adjustable guide vane is fixedly arranged in the first volute and is positioned at the right end of the first impeller.

Preferably, a first-stage sealing wheel cover is arranged on the outer surface of the first impeller, and a second-stage sealing wheel cover is arranged on the outer surface of the second impeller.

Preferably, the first-stage diffuser and the second-stage diffuser are respectively provided with a sealing tooth structure at the end part of the plugging main shaft, and the first-stage sealing wheel cover and the second-stage sealing wheel cover are respectively provided with a sealing tooth structure.

Preferably, a gap is arranged between the primary sealing wheel cover and the first impeller, a gap is also arranged between the secondary sealing wheel cover and the second impeller, and the size of the gap is 0.1mm-0.5mm.

Preferably, the second-stage volute is provided with a gas supplementing port communicated with the second gas inlet.

Preferably, a flange is arranged at the left end of the two-stage volute, the middle part of the flange is aligned with the inlet of the second air inlet, a gap is arranged between the flange and the second air inlet, and the range of the gap is 0.5mm-3mm.

In summary, the invention has the advantages that:

1. The compressor adopts a closed three-element flow vane type design, combines a permanent magnet variable frequency motor technology and a magnetic suspension bearing technology, realizes wide-range speed regulation operation of the compressor, has high rotating speed and large operation pressure ratio, greatly widens the operation range of the compressor, and can be applied to different fields. The magnetic suspension bearing technology enables the compressor to realize oil-free operation, an oil circuit circulation system is omitted, and the compressor is more energy-saving and environment-friendly.

2. The first impeller and the second impeller are respectively arranged at two ends of the main shaft, and the axial force is reduced to facilitate the axial control of the compressor.

3. The impeller wheel cover and the wheel disc are provided with sealing tooth structures, the diffuser is simple and reliable in structural design, reasonable in structural design and convenient to assemble.

4. Adopt refrigerant cooling motor, cooling channel is linked together with the gas circulation structure of compressor, after the cooling channel cools down the motor cooling to refrigerant liquid, the rethread induction port passageway and with the low-temperature low-pressure refrigerant gas mixture in the first air inlet can form superheated steam, inside the hot steam rethread first air inlet gets into the compressor, from this partial refrigerant has carried the circulation process of the initiative participation compressor of heat behind the cooling motor, the internal circulation of compressor has been realized, be favorable to increasing the superheat degree of the first air inlet of compressor, can prevent effectively that the compressor from breathing in and taking the liquid, and reduce the return air pipeline of compressor, the integrated level is high, structural arrangement is compacter.

Drawings

FIG. 1 is a schematic diagram of a magnetic levitation centrifugal heat pump compressor operating with wide frequency conversion;

FIG. 2 is a cross-sectional view of the compressor;

FIG. 3 is a cross-sectional view of the compressor cooling passage;

FIG. 4 is a partial cross-sectional view of the first impeller;

FIG. 5 is a partial cross-sectional view of the second impeller;

The reference numerals are 1, a housing, 2, a gas circulation structure, 3, a motor assembly, 11, a suction housing, 12, a first volute, 13, a second volute, 14, a gas supplementing port, 15, a flange, 16, a gap, 21, a first gas inlet, 22, a suction assembly, 23, a gas exhausting assembly, 24, a gas transmission channel, 25, an adjustable guide vane, 26, a seal tooth structure, 27, a gap, 31, a motor housing, 32, a main shaft, 33, a first bearing, 34, a second bearing, 35, a stator, 41, a liquid supply inlet, 42, a spiral groove, 43, a liquid supply outlet, 44, a first channel, 45, a first cavity, 46, a second channel, 47, a rotor air gap, 48, a third channel, 49, a first volute channel, 50, a first impeller, 222, a first gas suction inlet, 223, a first gas suction inlet, 224, a first sealing wheel cover, 231, a second impeller, 232, a second diffuser, 233, a second gas inlet, 234, a second gas outlet, 235, and a second sealing wheel cover.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

In the description of the present application, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present application and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application.

It should also be noted that like reference numerals and letters refer to like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

The following describes the embodiments of the present invention in detail with reference to the drawings.

As shown in fig. 1 to 5, the magnetic suspension centrifugal heat pump compressor for wide frequency conversion operation comprises a shell 1, a gas circulation structure 2 and a motor assembly 3, wherein the gas circulation structure 2 and the motor assembly 3 are arranged inside the shell 1, the shell 1 comprises a gas suction shell 11, a first-stage volute 12, a motor shell 31 and a second-stage volute 13, the second-stage volute 13 and the first-stage volute 12 are respectively and fixedly connected to the left end and the right end of the motor shell 31, the gas suction shell 11 is fixedly arranged at the right end of the first-stage volute 12, the gas circulation structure 2 comprises a first gas inlet 21, the first gas inlet 21 is arranged on the gas suction shell 11 and is communicated with the first-stage volute 12, the motor assembly 3 comprises a main shaft 32, a first bearing 33, a second bearing 34 and a stator 35, the second bearing 34 and the first bearing 33 are respectively arranged at the left end and the right end of the motor shell 31, the main shaft 32 is erected at the middle of the first bearing 33 and the second bearing 34, the stator 35 is arranged at the middle of the main shaft 32, the main shaft is made of a permanent magnet material, the main shaft is a rotor, and a permanent magnet material is adopted for enabling the rotor to rotate at a high speed, the high efficiency and can realize high-speed and high-torque operation in a large-range operation, and high-efficiency operation can be realized in a large-range operation range, and high-speed operation can be realized. The first bearing and the second bearing adopt magnetic suspension bearings, and the main shaft is supported in a non-contact manner through a magnetic suspension technology to rotate at a high speed, so that lubricating oil is saved for lubrication and cooling.

The compressor is internally provided with a cooling channel, the cooling channel comprises a motor cooling channel, a steering channel and a discharge channel, and the motor cooling channel, the steering channel and the discharge channel are sequentially communicated; the motor cooling channel comprises a liquid supply inlet 41, a spiral groove 42 and a liquid supply outlet 43, wherein the liquid supply inlet 41, the spiral groove 42 and the liquid supply outlet 43 are all arranged in the middle of the motor shell 31, the spiral groove 42 is arranged around the outer ring of the stator 35, and the liquid supply inlet 41 which is longitudinally arranged and the liquid supply outlet 43 which is transversely arranged are respectively communicated with two ends of the spiral groove 42; the steering passage comprises a first passage 44, a first cavity 45 and a second passage 46 which are sequentially connected, the first cavity 45 is arranged between the second bearing 34 and the motor housing 31, the second passage 46 is axially arranged in the second bearing 34, the first passage 44 is arranged on the outer diameter of the second bearing 34 and axially penetrates through the second bearing 34, the right end of the first passage 44 is communicated with the left end of the liquid supply outlet 43, the discharging passage comprises a rotor air gap 47, a third passage 48, a volute passage one 49 and an air suction passage 50 which are sequentially connected, the rotor air gap 47 is arranged between the stator 35 and the main shaft 32, the third passage 48 is axially arranged in the first bearing 33, the volute passage one 49 is arranged in the first volute 12, the air suction passage 50 is arranged in the suction housing 11, the rotor air gap 47 is communicated with the second passage 46, the air suction passage 50 is connected with the first air inlet 21 of the compressor, the refrigerant is mixed with low-temperature and low-pressure refrigerant gas in the first air inlet 21 after flowing through the cooling passage can form superheated steam, the hot steam enters the first air inlet 21 through the first air inlet 21, the part of refrigerant carries heat after cooling the motor, actively participates in the circulation process of the compressor, realizes the internal circulation of the compressor, is favorable for increasing the superheat degree of the first air inlet of the compressor, can effectively prevent the air suction and liquid carrying of the compressor, reduces the air return pipeline of the compressor, and has high integration degree and more compact structural arrangement. .

The gas circulation structure 2 further comprises a suction assembly 22, The exhaust assembly 22 comprises a first impeller 221 and a first diffuser 222, wherein the first impeller 221 is arranged in the first air inlet 21, one surface with larger surface area is fixedly connected to the right end of the main shaft 32 through bolts, the first diffuser 222 is clamped between a first bearing 33 and the first impeller 221 and is inserted into the outer diameter of the right end of the main shaft 32, the first volute is provided with a first air suction port 223 which passes through the first diffuser 222 and is communicated with the first impeller 221, the first air suction port 223 is communicated with one end of the air transmission channel 24, when air flows into the first air suction port 223, the air can pass through the first impeller 221 and the first diffuser 222, and is conveyed to the air transmission channel 24 through the first air suction port 223 after being heated and pressurized, the second impeller 231 is arranged in the second stage 13, one surface with larger surface area is fixedly connected to the left end of the main shaft 32 through bolts, the second diffuser 232 is clamped between the second impeller 34 and the second impeller 233 and is communicated with the first air suction port 221, the first air suction port 223 is communicated with the second air outlet 233 is arranged at one end of the second volute, the second air suction port 233 is communicated with the second air outlet 234, the second air inlet 13 is arranged at the other end of the second volute is communicated with the second air inlet 233, and the second air inlet 233 is communicated with the second air outlet 234, and the second air outlet is communicated with the second air inlet 13. An adjustable guide vane 25 is further arranged in the first air inlet 21, and the adjustable guide vane 25 is fixedly arranged in the first-stage volute 12 and is positioned at the right end of the first impeller 221. The first impeller 221 has a primary seal shroud 224 on its outer surface, and the second impeller 231 has a secondary seal shroud 235 on its outer surface. The primary diffuser 222 and the secondary diffuser 232 are provided with seal tooth structures 26 at the end of the plugging main shaft 32, and the primary seal wheel cover 224 and the secondary seal wheel cover 235 are also provided with seal tooth structures 26. A gap 27 is arranged between the primary sealing wheel cover 224 and the first impeller 221, a gap 27 is also arranged between the secondary sealing wheel cover 235 and the second impeller 231, and the size of the gap 27 is 0.1mm-0.5mm. The secondary volute 13 is provided with a gas supplementing port 14 communicated with the second gas inlet 233. A flange 15 is arranged at the left end of the two-stage volute 13, the middle part of the flange 15 is aligned with the inlet of the second air inlet 233, a gap 16 is arranged between the flange 15 and the second air inlet 233, and the range of the gap 16 is 0.5mm-3mm. The first impeller 221 and the second impeller 231 are designed in a closed three-way flow vane type, the efficiency is higher, the noise is lower, the first impeller 221 and the second impeller 231 are respectively arranged at two ends of the main shaft, the effect of balancing axial force is achieved, the axial control is facilitated, the first impeller 221 and the second impeller 231 are designed in a large pressure ratio, the highest running pressure ratio can reach 6.0, the highest running pressure ratio is far higher than that of products of the same type, the air conditioner can be operated in a heat pump working condition, an air cooling working condition, an industrial cooling working condition, an ice storage working condition and the like, the running condition of running air conditioner cooling water can be considered, and the running range of the compressor is greatly increased.

As shown in figures 1 to 3, the compressor adopts a magnetic suspension bearing technology and a permanent magnet variable frequency motor driving technology, so that an oil system is not needed, the reliability of a unit can be remarkably improved, oil detection is not needed regularly, and the maintenance is simple and convenient. The motor assembly 3 for magnetic levitation includes a motor housing 31, a main shaft 32, a first bearing 33, a second bearing 34, and a stator 35, wherein the second bearing 34 and the first bearing 33 are disposed at left and right ends of the motor housing 31, the main shaft 32 is disposed at middle portions of the first bearing 33 and the second bearing 34, and the stator 35 is disposed at middle portions of the main shaft 32.

As shown in fig. 3, a cooling passage is provided inside the compressor for cooling down the motor inside. The cooling channel comprises a motor cooling channel, a steering channel and a discharge channel which are sequentially communicated, and the three channels are arranged to effectively cool the motor. The motor cooling channel comprises a liquid supply inlet 41, a spiral groove 42 and a liquid supply outlet 43, wherein the liquid supply inlet 41, the spiral groove 42 and the liquid supply outlet 43 are all arranged in the middle of the motor shell 31, the spiral groove 42 is arranged around the outer ring of the stator 35, the liquid supply inlet 41 is longitudinally arranged on the motor shell 31 and used for inputting refrigerant liquid, the liquid supply outlet 43 is transversely arranged on the motor shell 31 and used for conveying the refrigerant liquid to other channels, the liquid supply outlet 43 and the liquid supply inlet 41 are respectively communicated with two ends of the spiral groove 42, and when the refrigerant liquid enters from the liquid supply inlet 41, the stator 35 is cooled in the motor cooling channel first and flows into the steering channel from the liquid supply outlet 43.

The steering channel comprises a first channel 44, a first cavity 45 and a second channel 46 which are sequentially connected, the first cavity 45 is arranged between the second bearing 34 and the motor shell 31, the second channel 46 is axially arranged in the second bearing 34, the first channel 44 is arranged on the outer diameter of the second bearing 34 and axially penetrates through the second bearing 34, the right end of the first channel 44 is communicated with the left end of the liquid supply outlet 43, when the refrigerant liquid flows into the first channel 44 from the liquid supply outlet 43, the refrigerant liquid flows into the first cavity 45 on the left side and then turns to the second channel 46 on the right side of the cavity, and then the refrigerant liquid cools the second bearing 34 in the process flows into the discharging channel.

The discharge passage includes a rotor air gap 47, a third passage 48, a first volute passage 49 and an air suction passage 50 which are sequentially connected, the rotor air gap 47 is arranged between the stator 35 and the main shaft 32, the third passage 48 is axially arranged in the first bearing 33, the first volute passage 49 is arranged in the first volute 12, the air suction passage 50 is arranged on the suction casing 11, wherein the rotor air gap 47 is communicated with the second passage 46, when the refrigerant liquid flows into the rotor air gap 47 from the second passage 46, the stator 35 is cooled down secondarily, the cooling effect can be better realized, the refrigerant liquid moves to the third passage 48 on the right side of the rotor air gap 47, the first bearing 33 is cooled down, and after the cooling of the motor assembly 3 is completed, the refrigerant liquid flows out from the first volute passage 49 and the air suction passage 50, wherein the air suction passage 50 is connected with the first air inlet 21 of the compressor.

The refrigerant liquid flows through the suction port channel 50 and is mixed with the low-temperature low-pressure refrigerant gas in the first air inlet 21 to form superheated steam, and the superheated steam enters the gas circulation structure 2 through the first air inlet 21, so that the circulation process of the compressor can be actively participated, the performance of the compressor can be improved, the connection and the exchange of the compressor and the outside are reduced, the structure is more compact, and the cost of equipment is reduced. The motor component 3 is cooled by adopting refrigerant liquid, the cooling medium is clean and free of stains, phase change heat absorption can be realized in the cooling process of the refrigerant, and the cooling effect is excellent. The refrigerant absorbs the heat of the motor and becomes superheated steam, so that the refrigerant gas sucked into the compressor has a certain degree of superheat, and the suction liquid of the compressor can be effectively prevented. Because the cooling channels participating in circulation are completely integrated in the compressor, the integration level is higher, and the external pipelines and the control system are greatly simplified.

As shown in fig. 2, the gas circulation structure 2 of the whole compressor comprises a first gas inlet 21, a suction assembly 22, a discharge assembly 23 and a gas transmission channel 24, wherein the suction assembly 22 comprises a first impeller 221 and a first-stage diffuser 222, the first impeller 221 is arranged in the first gas inlet 21, one surface with larger surface area is fixedly connected to the right end of a main shaft 32 through bolts, the first-stage diffuser 222 is clamped between a first bearing 33 and the first impeller 221 and is inserted on the outer diameter of the right end of the main shaft 32, the first volute is provided with a first-stage suction port 223 which passes through the first-stage diffuser 222 and is communicated with the first impeller 221, the first-stage suction port 223 is communicated with one end of the gas transmission channel 24, when refrigerant gas enters the first gas inlet 21, the first impeller 221 moves leftwards under the rotation of the first impeller 221, and after the gas passes through the first-stage diffuser 222, the first-stage diffuser 222 becomes high-temperature high-pressure refrigerant gas, and the high-pressure refrigerant gas at this time is transmitted from the first-stage suction port 223 connected with the gas transmission channel 24 into the discharge assembly 23.

The exhaust assembly 23 comprises a second impeller 231 and a second diffuser 232, the second impeller 231 is arranged in the second volute 13, one surface with larger surface area is fixedly connected to the left end of the main shaft 32 through bolts, the second diffuser 232 is clamped between the second bearing 34 and the second impeller 231 and inserted on the outer diameter of the left end of the main shaft 32, a second air outlet 234 which passes through the second diffuser 232 and is communicated with the second impeller 231 is further arranged on the second volute, the second air outlet 234 is communicated to the outer surface of the second volute 13, a second air inlet 233 is arranged on the second volute 13, the second impeller 231 is arranged in the second air inlet 233, and the other end of the air transmission channel 24 is connected to the second air inlet 233. When the refrigerant gas is delivered from the first air suction port 223 to the second air intake port 233, the second impeller 231 and the second diffuser 232 compress the gas again to become refrigerant gas with higher pressure and temperature, and the gas is discharged from the second air outlet 234, and the discharged refrigerant gas with high temperature and high pressure is circulated by the refrigeration cycle principle and then becomes gas with low temperature and low pressure to reenter the first air intake port 21, so that the compressor is driven to continuously provide power for the whole cycle.

As shown in fig. 1 to 3, the adjustable guide vane 25 is additionally arranged in the first air inlet 21, the adjustable guide vane 25 and the first impeller 221 are both arranged in the first volute 12, wherein the adjustable guide vane 25 is arranged at the right end of the first impeller 221, so that the flow rate of gas entering the compressor can be controlled, the occupied space is small, the worm and gear transmission torque is large, the control is simple and convenient, the guide vane mechanism is also provided with accurate mechanical limit, the long-term reliable operation of the guide vane is ensured, the adjustable range of the adjustable guide vane 25 is 10-100%, the adjusting range is wide, the load adjusting range of the compressor can be greatly increased, the lead-out wire of the stepping motor is routed inside the compressor, the excessive lead-out wire requirement is avoided, and the whole structure is simple.

As shown in fig. 4 to 5, the first impeller 221 is provided with a first-stage sealing wheel cover 224 on its outer surface, and the second impeller 231 is provided with a second-stage sealing wheel cover 235 on its outer surface, so that the integrity of the two impellers can be ensured, and the two impellers are not easily damaged. The first impeller 221 and the first seal wheel cover 224 are disposed in the first scroll casing 12, and since the first scroll casing 12 cannot be bonded to the first seal wheel cover 224 in pairs, a gap 27 with a certain size is disposed between the first scroll casing 12 and the first seal wheel cover, and the gap 27 is in a range of 0.1mm-0.5mm, if the gap 27 is not disposed there, the equipment cannot operate normally. And the second impeller 231 and the second-stage seal shroud 235 are provided with the same size of gap 27 as the second-stage volute 13.

The outer curved surface of the primary seal wheel cover 224 is provided with a seal tooth structure 26, the seal tooth structure 26 is close to one end with smaller surface area of the first impeller 221, and the outer curved surface of the secondary seal wheel cover 235 is also provided with a seal tooth structure 26, and the seal tooth structure 26 is close to one end with smaller surface area of the first impeller 221. The provision of the seal tooth structure 26 reduces the amount of leakage of gas and thus increases the efficiency of the machine. The seal tooth structure 26 is likewise provided at the end of the plug main shaft 32 at the primary diffuser 222 and the secondary diffuser 232.

As shown in fig. 1, the air supply port 14 is provided on the compressor, and the air supply port 14 of the compressor is provided on the two-stage volute 13 and is communicated with the second air inlet 233, and by inputting the newly added air from the air supply port 14 into the compressor, the circulation system can achieve the effect of air supply and enthalpy increase, and the energy efficiency of the system can be greatly increased.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art. The generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A wide-range variable frequency magnetic levitation centrifugal heat pump compressor, the compressor comprising a housing (1), a gas circulation structure (2), and a motor assembly (3), wherein the gas circulation structure (2) and the motor assembly (3) are both disposed inside the housing (1); the housing (1) comprises an intake housing (11) and a primary volute (12). The motor housing (31) and the secondary volute (13) are fixedly connected to the left and right ends of the motor housing (31), respectively. The intake housing (11) is fixedly installed at the right end of the primary volute (12). The gas circulation structure (2) includes a first air inlet (21), which is installed on the intake housing (11) and connected to the primary volute (12). The motor assembly (3) includes a main shaft (32), a first bearing (33), a second bearing (34), and a stator (35). The second bearing (34) and the first bearing (33) are respectively installed at the left and right ends of the motor housing (31). The main shaft (32) is mounted in the middle of the first bearing (33) and the second bearing (34). The stator (35) is installed in the middle of the main shaft (32).

The compressor is characterized by having a cooling channel, which includes a motor cooling channel, a steering channel, and a discharge channel, which are connected in sequence. The motor cooling channel includes a liquid inlet (41), a spiral groove (42), and a liquid outlet (43). The liquid inlet (41), spiral groove (42), and liquid outlet (43) are all located in the middle of the motor housing (31). The spiral groove (42) surrounds the outer ring of the stator (35). The longitudinally arranged liquid inlet (41) and the transversely arranged liquid outlet (43) are connected to the two ends of the spiral groove (42). The steering channel includes a first channel (44), a first cavity (45), and a second channel (46) connected in sequence. The first cavity (45) is located between the second bearing (34) and the motor housing (31). The second channel (46) is axially located inside the second bearing (34). The first channel (44) is located on the outer diameter of the second bearing (34) and extends axially through the second bearing (34). The right end of the first channel (44) is connected to the left end of the liquid supply outlet (43). The discharge channel includes a rotor air gap (47), a third channel (48), a volute channel (49), and an air intake channel (50) connected in sequence. The rotor air gap (47) is located between the stator (35) and the main shaft (32). The third channel (48) is axially located on the first bearing (33). Inside the compressor, the first volute channel (49) is located inside the first volute (12), and the suction port channel (50) is located on the suction housing (11). The rotor air gap (47) is connected to the second channel (46), and the suction port channel (50) is connected to the first air inlet (21) of the compressor. After the refrigerant flows through the cooling channel, it mixes with the low temperature and low pressure refrigeration gas in the first air inlet (21) to form superheated steam. The hot steam then enters the compressor through the first air inlet (21). Thus, this part of the refrigerant carries the heat after cooling the motor and actively participates in the compressor's cycle process.

2. The magnetic levitation centrifugal heat pump compressor with wide-range variable frequency operation according to claim 1, characterized in that the gas circulation structure (2) further includes an intake assembly (22), an exhaust assembly (23), and a gas transmission channel (24);

The intake assembly (22) includes a first impeller (221) and a first-stage diffuser (222). The first impeller (221) is disposed inside the first air inlet (21), and its larger surface area side is fixedly connected to the right end of the main shaft (32) by bolts. The first-stage diffuser (222) is sandwiched between the first bearing (33) and the first impeller (221) and is inserted into the outer diameter of the right end of the main shaft (32). The first-stage volute is provided with a first-stage intake port (223) that passes through the first-stage diffuser (222) and communicates with the first impeller (221). The first-stage intake port (223) is connected to one end of the gas transmission channel (24).

The exhaust assembly (23) includes a second impeller (231) and a secondary diffuser (232). The second impeller (231) is disposed inside the secondary volute (13), and its larger surface area side is fixedly connected to the left end of the main shaft (32) by bolts. The secondary diffuser (232) is sandwiched between the second bearing (34) and the second impeller (231) and inserted into the outer diameter of the left end of the main shaft (32). The secondary volute is provided with a secondary air outlet (234) that passes through the secondary diffuser (232) and communicates with the second impeller (231). The secondary air outlet (234) communicates with the outer surface of the secondary volute (13).

The secondary volute (13) is provided with a second air inlet (233), the second impeller (231) is disposed in the second air inlet (233), and the other end of the gas transmission channel (24) is connected to the second air inlet (233).

3. A magnetic levitation centrifugal heat pump compressor with wide-range variable frequency operation according to claim 2, characterized in that an adjustable guide vane (25) is provided in the first air inlet (21), the adjustable guide vane (25) is fixedly installed in the first stage volute (12) and located at the right end of the first impeller (221).

4. A magnetic levitation centrifugal heat pump compressor with wide-range variable frequency operation according to claim 2, characterized in that the outer surface of the first impeller (221) is provided with a primary sealing wheel cover (224), and the outer surface of the second impeller (231) is provided with a secondary sealing wheel cover (235).

5. A magnetic levitation centrifugal heat pump compressor with wide-range variable frequency operation according to claim 4, characterized in that the first-stage diffuser (222) and the second-stage diffuser (232) are both provided with sealing tooth structures (26) at the ends of the main shaft (32), and the first-stage sealing wheel cover (224) and the second-stage sealing wheel cover (235) are also provided with sealing tooth structures (26).

6. A magnetic levitation centrifugal heat pump compressor with wide-range variable frequency operation according to claim 5, characterized in that a gap (27) is provided between the primary sealing wheel cover (224) and the first impeller (221), and a gap (27) is also provided between the secondary sealing wheel cover (235) and the second impeller (231), wherein the size of the gap (27) is 0.1mm-0.5mm.

7. A magnetic levitation centrifugal heat pump compressor with wide-range variable frequency operation according to claim 2, characterized in that the secondary volute (13) is provided with a supplementary air port (14) connected to the second air inlet (233).

8. A magnetic levitation centrifugal heat pump compressor with wide-range variable frequency operation according to claim 1, characterized in that a flange (15) is provided on the left end of the secondary volute (13), the middle part of the flange (15) is aligned with the inlet of the second air inlet (233), and a gap (16) is provided between the flange (15) and the second air inlet (233), the gap (16) being in the range of 0.5mm-3mm.