High-speed magnetic levitation motor direct-driven closed high-temperature turbine compression all-in-one machine

Abstract

The invention discloses a closed high-temperature turbine compression all-in-one machine directly driven by a high-speed magnetic levitation motor. A motor and a turbine are simple in cooling structure. A pressure end motor seal is arranged between the compressor impeller and the pressure end protection bearing, a turbine cooling seal and a vortex end motor seal are arranged among the compressor seal, the turbine turbine and the vortex end protection bearing, a heat exchanger is arranged on a motor shell, a branch pipe is arranged on an exhaust pipeline of the compressor and connected with the heat exchanger, and a stream of split-flow high-pressure gas is led out of the branch pipe. The split-flow high-pressure gas becomes high-pressure low-temperature gas after being cooled by a heat exchanger, the heat exchanger is connected with a branch pipeline, so that the high-pressure low-temperature gas is split into a first cooling gas path and a second cooling gas path, the first cooling gas path is connected with the pressure end of the motor shell through a first adjusting valve, and turbine shell cooling holes are formed in the gas inlet end of the turbine shell in the radial direction. The turbine shell cooling hole is communicated with a gap between the turbine cooling seal and the main shaft, and the second cooling gas circuit is connected with the turbine shell cooling hole through a second adjusting valve.

Description

Technical Field

[0001] The present invention relates to the technical field of turbine-compressor integrated machines, and in particular to a high-speed magnetic levitation motor directly driven enclosed high-temperature turbine-compressor integrated machine. Background Art

[0002] At present, the Brayton power generation system (hereinafter referred to as the system) is often used in power generation systems for small and medium power equipment. The media include CO2, helium, air, etc. The system mainly consists of: compressor (including drive motor), regenerator, heat exchanger, precooler, turbine (including generator).

[0003] In order to improve the power generation efficiency of the system, the system temperature and pressure parameters are relatively high. Taking the CO2 medium system as an example, the compressor and turbine pressure range is 8~20MPa, the turbine inlet temperature is 450~600℃, and the helium medium turbine inlet temperature is as high as 900℃.

[0004] The compressor is a power-consuming device, while the turbine is a power-generating device. In a system, the compressor (including the drive motor) and turbine (including the generator) are often combined into one unit, using a high-speed magnetic levitation motor (magnetic levitation motor) for direct drive. The compressor and turbine are suspended at either end of the motor, creating a turbine-compressor all-in-one unit. During startup, the motor acts as an electric motor, driving the compressor and turbine. As turbine parameters increase, turbine power output increases. Besides driving the compressor, excess power is output through the motor, which then acts as a generator. However, conventional all-in-one units typically use dry gas seals as shaft end seals to minimize leakage from the compressor and turbine shafts. This leaked gas is then drawn into the motor by a diaphragm compressor, pressurized, and then reinjected into the system to prevent leakage. The dry gas seal and reinjection system are complex to configure, occupy a large area, and are difficult to control, making them unsuitable for long-term operation. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a high-speed magnetic levitation motor directly driven enclosed high-temperature turbine compressor integrated machine, which has no dry gas seal, no cooling re-injection compressor, and a simple motor and turbine cooling structure.

[0006] The object of the present invention is achieved like this: A high-speed magnetic levitation motor directly driven enclosed high-temperature turbine compressor, comprising a motor, a compressor and a turbine, wherein the motor comprises a motor housing and a main shaft, a stator is installed in the motor housing, a magnetic levitation thrust bearing and a permanent magnet are installed between the middle of the main shaft and the motor housing, the permanent magnet corresponds to the stator, a pressure end magnetic levitation radial bearing and a pressure end protection bearing are installed between the pressure end of the main shaft and the motor housing, a vortex end magnetic levitation radial bearing and a vortex end protection bearing are installed between the vortex end of the main shaft and the motor housing, the compressor comprises a compressor housing and a compressor impeller, the turbine comprises a turbine housing and a turbine turbine, the compressor housing and the turbine housing are fixedly mounted on both ends of the motor housing, the compressor impeller and the turbine turbine are connected to both ends of the main shaft, the compressor housing comprises a compressor air inlet and a compressor exhaust pipeline, and the turbine housing comprises a turbine air inlet pipeline and a turbine exhaust. A compression end motor seal and a compressor seal are provided between the compressor impeller and the compression end protection bearing. The compression end motor seal is installed between the motor housing and the main shaft. The compressor seal is installed between the compressor housing and the main shaft. A turbine cooling seal and a turbine end motor seal are provided between the turbine turbine and the turbine end protection bearing. The turbine end motor seal is installed between the motor housing and the main shaft. The turbine cooling seal is installed between the turbine housing and the main shaft. After the high-pressure, low-temperature gas in the first cooling gas path enters the interior of the motor housing, since the pressure at the back of the compressor impeller is second only to the high-pressure gas diverted from the compressor outlet, and the pressure at the back of the turbine wheel is the lowest, a small portion of the high-pressure, low-temperature gas in the first cooling gas path leaks into the interior of the compressor through the compression end protection bearing, the compression end motor seal, and the compressor seal. The majority of the high-pressure, low-temperature gas in the first cooling gas path passes through the cooling magnetic levitation radial bearing, the permanent magnet, the magnetic levitation thrust bearing, the magnetic levitation thrust bearing, the magnetic levitation radial bearing, and then leaks into the interior of the turbine housing through the turbine end protection bearing, the turbine end motor seal, and the turbine cooling seal. After the high-pressure, low-temperature gas in the first cooling gas path enters the interior of the motor housing, a small portion of the high-pressure, low-temperature gas in the first cooling gas path leaks into the interior of the compressor through the compression end protection bearing, the compression end motor seal, and the compressor seal in sequence. The majority of the high-pressure, low-temperature gas in the first cooling gas path passes through the cooling magnetic levitation radial bearing, the permanent magnet, the magnetic levitation thrust bearing, the magnetic levitation thrust bearing, the magnetic levitation radial bearing in sequence, and then leaks into the interior of the turbine housing through the turbine end protection bearing, the turbine end motor seal, and the turbine cooling seal. A turbine casing cooling hole is radially provided at the air inlet end of the turbine casing. The turbine casing cooling hole is connected to the gap between the turbine cooling seal and the main shaft. The gap is a merging gap. The second cooling air path is connected to the turbine casing cooling hole through a second regulating valve. The high-pressure and low-temperature gas of the second cooling air path is passed into the turbine casing cooling hole after the flow rate is adjusted by the second regulating valve. The high-pressure and low-temperature gases of the second cooling air path and the first cooling air path are merged in the merging gap and then passed into the turbine intake pipe to cool the turbine casing and the main shaft.

[0007] Preferably, a cooling water channel is provided on the motor housing, the cooling water channel having a cooling water inlet and a cooling water outlet, and the cooling water channel cools the motor stator and the motor housing through cooling water.

[0008] Preferably, a radial cooling channel is provided between the large end of the turbine and the turbine cooling seal, and both ends of the radial cooling channel are respectively connected to the converging gap and the turbine intake pipe, and the radial cooling channel is used to cool the turbine casing.

[0009] Preferably, the turbine housing cooling holes are arranged along the turbine cooling seal surface, so that high-pressure and low-temperature gas flows along the turbine cooling seal surface, cools the turbine cooling seal, and then cools the turbine housing and main shaft through the turbine cooling seal.

[0010] Due to the adoption of the above technical solution, the present invention has the following beneficial effects: There is no dry gas seal, no cooling re-injection compressor, and the motor and turbine cooling structure is simple, which solves the problems of complex configuration of auxiliary equipment, large space occupation and high control difficulty of the turbine-compressor integrated unit of the Brayton power generation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of a high-speed magnetic levitation motor directly driven enclosed high-temperature turbine compressor. Attached photos

[0012] In the accompanying drawings, 1-compressor air inlet; 2-compressor exhaust pipeline; 3-diverted high-pressure gas; 4-heat exchange cold water inlet; 5-heat exchanger; 6-heat exchange cold water outlet; 7-first cooling air path; 8-first regulating valve; 9-second regulating valve; 10-second cooling air path; 11-turbine casing cooling hole; 12-turbine air inlet pipeline; 13-turbine exhaust port; 14-turbine casing; 15-turbine turbine; 16-turbine cooling seal; 17-turbine end motor seal; 18-cooling water outlet; 19, 30-protective bearings; 20, 29-magnetic levitation radial bearings; 21, 22-magnetic levitation thrust bearings; 23-main shaft; 24-stator; 25-permanent magnet; 26-cooling water channel; 27-cooling water inlet; 28-motor casing; 31-compression end motor seal; 32-compressor seal; 33-compressor impeller; 34-compressor casing. DETAILED DESCRIPTION

[0013] A high-speed magnetic levitation motor directly drives a sealed high-temperature turbine compressor. In the present invention, the compressor impeller 33 and the turbine turbine 15 are suspended at both ends of the main shaft 23, and the compressor housing 34 and the turbine housing 14 are suspended at both ends of the motor housing 28. A stator 24 is installed inside the motor housing 28 for generating electromagnetic torque, which acts on the permanent magnet 25 attached to the main shaft 23 to drive the main shaft 23 to rotate. Magnetic levitation radial bearings 29 and 20, magnetic levitation thrust bearings 22 and 21, and pressure end protection bearings 30 and 19 are installed on both sides of the stator, which are respectively used to support the main shaft suspension during operation, withstand bidirectional thrust, and support the main shaft rotation when the magnetic levitation bearings fail in unexpected working conditions.

[0014] The compression end motor seal 31 and the compressor seal 32 are installed between the compressor impeller 33 and the compression end protection bearing 30, and the turbine cooling seal 16 and the turbine end motor seal 17 are installed between the turbine turbine 15 and the turbine end protection bearing 19, which are used to reduce the gas leakage between the inside of the motor and the compressor housing and the turbine housing.

[0015] The motor housing 28 is integrated with a heat exchanger 5. A stream of high-pressure gas 3 is drawn out from the compressor exhaust pipe 2. After passing through the heat exchanger 5, it becomes high-pressure and low-temperature gas, which is divided into a first cooling gas path 7 and a second cooling gas path 10 to cool the integrated machine: the first cooling gas path 7 enters the motor after the flow is adjusted by the first regulating valve 8. A small amount of gas leaks into the compressor through the pressure end protection bearing 30, the compressor seal 32, and the pressure end motor seal 31. Most of the gas cools the magnetic levitation radial bearing 29, the permanent magnet 25, the stator 24, the magnetic levitation thrust bearing 22, the magnetic levitation thrust bearing 21, After passing through the magnetically levitated radial bearing 20, the air leaks into the turbine through the turbine end protection bearing 19, the turbine end motor seal 17, and the turbine cooling seal 16. The second cooling air path 10, after flow regulation by the second regulating valve 9, flows into the turbine casing cooling hole 11. It then merges with the first cooling air path 7 and flows into the turbine interior, cooling the turbine casing 14 and main shaft 23, reducing the heat transfer from the high temperature of the turbine casing and impeller to the motor casing and main shaft. Simultaneously, the combined cooling air enters the turbine turbine 15 for expansion and work, reducing some of the diversion losses from the main flow and improving the efficiency of the integrated unit and system. The heat exchanger 5 is equipped with a heat exchange cold water inlet 4 and a heat exchange cold water outlet 6. The motor casing 28 is provided with a cooling water channel 26. Cooling water enters through the inlet 27 and is discharged through the outlet 18, cooling the motor stator 24 and motor casing 28.

[0016] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A high-speed magnetic levitation motor directly driven enclosed high-temperature turbine compressor, comprising a motor, a compressor, and a turbine, wherein the motor comprises a motor housing and a main shaft, a stator being installed in the motor housing, a magnetic levitation thrust bearing and a permanent magnet being installed between the middle of the main shaft and the motor housing, the permanent magnet corresponding to the stator, a pressure end magnetic levitation radial bearing and a pressure end protection bearing being installed between the pressure end of the main shaft and the motor housing, a vortex end magnetic levitation radial bearing and a vortex end protection bearing being installed between the vortex end of the main shaft and the motor housing, the compressor comprising a compressor housing and a compressor impeller, the turbine comprising a turbine housing and a turbine turbine, the compressor housing and the turbine housing being fixedly mounted on both ends of the motor housing, the compressor impeller and the turbine turbine being connected to both ends of the main shaft, the compressor housing comprising a compressor air inlet and a compressor exhaust pipe, and the turbine housing comprising a turbine air inlet pipe and a turbine exhaust port, characterized in that: A compression end motor seal and a compressor seal are provided between the compressor impeller and the compression end protection bearing. The compression end motor seal is installed between the motor housing and the main shaft. The compressor seal is installed between the compressor housing and the main shaft. A turbine cooling seal and a turbine end motor seal are provided between the turbine turbine and the turbine end protection bearing. The turbine end motor seal is installed between the motor housing and the main shaft. The turbine cooling seal is installed between the turbine housing and the main shaft. A heat exchanger is provided on the motor housing. The heat exchanger is provided with a heat exchange cold water inlet and a heat exchange cold water outlet. A branch pipe is provided on the compressor exhaust pipe, the branch pipe is connected to the heat exchanger, and a branch high-pressure gas is drawn out from the branch pipe. The branch high-pressure gas is cooled by the heat exchanger and becomes a high-pressure low-temperature gas. The heat exchanger is connected to a bifurcated pipeline, so that the high-pressure low-temperature gas is split into a first cooling gas path and a second cooling gas path. The first cooling gas path is connected to the pressure end of the motor housing through a first regulating valve. The high-pressure low-temperature gas in the first cooling gas path enters the interior of the motor housing after the flow rate is adjusted by the first regulating valve. After the high-pressure, low-temperature gas in the first cooling gas path enters the interior of the motor housing, since the pressure at the back of the compressor impeller is second only to the high-pressure gas diverted from the compressor outlet, and the pressure at the back of the turbine wheel is the lowest, a small portion of the high-pressure, low-temperature gas in the first cooling gas path leaks into the interior of the compressor through the compression end protection bearing, the compression end motor seal, and the compressor seal. The majority of the high-pressure, low-temperature gas in the first cooling gas path passes through the cooling magnetic levitation radial bearing, the permanent magnet, the magnetic levitation thrust bearing, the magnetic levitation thrust bearing, the magnetic levitation radial bearing, and then leaks into the interior of the turbine housing through the turbine end protection bearing, the turbine end motor seal, and the turbine cooling seal. A turbine casing cooling hole is radially provided at the air inlet end of the turbine casing. The turbine casing cooling hole is connected to the gap between the turbine cooling seal and the main shaft. The gap is a merging gap. The second cooling air path is connected to the turbine casing cooling hole through a second regulating valve. The high-pressure and low-temperature gas of the second cooling air path is passed into the turbine casing cooling hole after the flow rate is adjusted by the second regulating valve. The high-pressure and low-temperature gases of the second cooling air path and the first cooling air path are merged in the merging gap and then passed into the turbine intake pipe to cool the turbine casing and the main shaft.

2. The high-speed magnetic levitation motor directly driven enclosed high-temperature turbine compressor according to claim 1, characterized in that: A cooling water channel is provided on the motor housing. The cooling water channel has a cooling water inlet and a cooling water outlet. The cooling water channel cools the motor stator and the motor housing through cooling water.

3. The high-speed magnetic levitation motor directly driven enclosed high-temperature turbine compressor according to claim 1, characterized in that: A radial cooling channel is provided between the big end of the turbine and the turbine cooling seal. The two ends of the radial cooling channel are respectively connected to the converging gap and the turbine intake pipe. The radial cooling channel is used to cool the turbine casing.

4. The high-speed magnetic levitation motor directly driven enclosed high-temperature turbine compressor according to claim 3, characterized in that: The turbine casing cooling holes are arranged along the turbine cooling sealing surface so that the high-pressure and low-temperature gas flows along the turbine cooling sealing surface.

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