WO2025138130A1 - Compressor-expander unit for high-temperature heat pump and high-temperature heat pump energy storage system - Google Patents

Abstract

A compressor-expander unit for a high-temperature heat pump, the compressor-expander unit comprising a compressor and an expander. The compressor comprises a rotor assembly, a stator assembly, and a housing assembly, wherein the rotor assembly comprises multi-stage moving blades (25), an inlet angle of the moving blades (25) being set within a range of -55° to 65°, and an outlet angle of the moving blades (25) being set within a range of -45° to 55°; the stator assembly comprises guide vanes (7) and multi-stage stationary blades (8), an inlet angle of the stationary blades (8) being set within a range of 40° to 50°, an outlet angle of the stationary blades (8) being set within a range of 10° to 30° and decreasing stage by stage, an inlet angle of the guide vanes (7) being set as 0°, and an outlet angle of the guide vanes (7) being set within a range of 30° to 40°; and a spacing between rows of the moving blades (25) and rows of the stationary blades (8) is set to be reduced stage by stage and is set within a range of 9-35 mm. The housing assembly comprises a compressor housing (1), wherein an air inlet and an air outlet are formed in the compressor housing (1) in a radial direction. Further provided is a high-temperature heat pump energy storage system, comprising a compressor-expander unit for a high-temperature heat pump. The compressor-expander unit for a high-temperature heat pump can effectively adapt to working conditions with a high air inlet temperature and temperature fluctuations, so that the efficiency and service life of the compressor can be improved.

Description

Compression expansion unit for high temperature heat pump and high temperature heat pump energy storage system Technical Field

The present invention relates to the field of energy technology, and in particular to a compression expansion unit for a high-temperature heat pump and a high-temperature heat pump energy storage system.

Background Art

With the rapid development and expansion of new energy, the demand for energy storage is constantly expanding. Compressors and expanders are one of the core equipment of heat pump energy storage technology. Temperature is the most important parameter of compressors. How to increase the temperature of the compressor outlet at low cost and high efficiency is one of the important topics in the application of compressors in the field of heat pump energy storage.

The intake temperature of conventional compressors is relatively low and relatively stable. When encountering high temperature conditions, the bearing parts, lubricating oil, etc. of the compressor cannot withstand the high temperature and work normally. In this case, expensive materials are generally used to meet the performance requirements under high temperature working conditions, which increases the cost. And when the intake temperature of the compressor is high and there are temperature fluctuations, it will greatly affect the stability and efficiency of the compressor. Therefore, there is an urgent need for a compressor design that can meet high temperature conditions to achieve safe and efficient operation of the compressor.

Summary of the invention

In view of the deficiencies in the prior art, the present invention provides a compression expansion unit for a high-temperature heat pump and a high-temperature heat pump energy storage system, which solves the problems in the prior art that when the intake temperature is high and there are temperature fluctuations, the current compressor cannot effectively adapt to such working conditions, resulting in reduced compressor efficiency and shortened life.

The above technical objectives of the present invention are achieved through the following technical solutions:

A compression expansion unit for a high-temperature heat pump comprises a multi-stage axial flow compressor and an axial flow expander, wherein the rotating shafts of the compressor and the expander run coaxially;

Wherein, the compressor comprises a rotor assembly, a stator assembly and a housing assembly;

A rotor assembly is used to impart kinetic energy to the gas and drive the gas to move axially inside the compressor; the rotor assembly includes multiple stages of moving blades, the inlet angle of the moving blades is set to -55 to 65 degrees, and the outlet angle of the moving blades is set to -45 to -55 degrees;

A stator assembly is used to convert the kinetic energy of the gas into pressure energy and adjust the gas flow direction; the stator assembly includes a guide vane and a multi-stage stationary vane, the inlet angle of the stationary vane is set to 40-50°, the outlet angle of the stationary vane is set to 10-30° and decreases step by step; the inlet angle of the guide vane is set to 0°, and the outlet angle of the guide vane is set to 30-40°;

The blade row spacing values of the moving blades and the stationary blades are set to 9 to 35 mm, and the values are gradually reduced;

The housing assembly comprises a compressor housing, a compressor air inlet and a compressor exhaust port are arranged on the compressor housing, and the compressor The axial directions of the air inlet of the machine and the exhaust port of the compressor are respectively N° and M° with the axis of the main shaft in the compressor, wherein 0＜N＜180, 0＜M＜180.

In the present application, the application scenario of the compressor has the following characteristics: in the present application, for the working condition of the inlet temperature of 100-200°C, the temperature difference is large, the inlet temperature is high and fluctuates; and the outlet temperature of the present application is high, exceeding 400°C, which has requirements for both structural design and material selection. Due to the wide temperature working condition, the blade row spacing of the moving blades and the stationary blades is too large, which will cause the compressor to have a reduced working capacity when other parameters remain unchanged, and cannot meet the condition of an outlet temperature of more than 400°C; or, the blade row spacing of the moving blades and the stationary blades is too large, which will cause other parameters such as the increase in the number of stages and the increase in blade parameters, thereby causing the inability to process, or other costs such as processing and design to rise sharply, which cannot meet the economic efficiency and does not meet the market needs; when the blade row spacing of the moving blades and the stationary blades is too small, and other parameters remain unchanged, although the compressor has a higher working capacity and a higher economic efficiency, due to the high temperature of the compressor, the blades will undergo axial thermal expansion in a high temperature environment, and then the adjacent blades will interfere after the compressor has been running for a period of time, which will reduce the service life of the compressor or the compressor cannot work normally. Therefore, the data selection for the moving blades, stationary blades and guide vanes in the present invention ensures both the safety of operation and the performance and working range. The radially arranged air inlet can ensure that the gas with poor uniformity can be mixed to a certain extent when entering the flow channel through the air inlet, thereby achieving better uniformity, and solving the problem of wide working conditions to a certain extent. The radially arranged air inlet combined with the setting of the stationary blades, guide vanes, moving blades, and row spacing can enable the compressor to meet the high temperature working conditions of the intake temperature of 100 to 200°C, while further meeting the requirements of higher efficiency, longer life and lower cost of the compressor.

Furthermore, the value of the outlet angle of the moving blades of the compressor first increases step by step and then decreases step by step along the direction of increasing gas temperature; and/or the value of the outlet angle of the primary moving blades of the compressor is greater than the value of the outlet angle of the final moving blades of the compressor.

Furthermore, the value of the inlet angle of the moving blades of the compressor first increases step by step and then decreases step by step along the direction of increasing gas temperature; and/or the value of the inlet angle of the primary moving blades of the compressor is greater than the value of the inlet angle of the final moving blades of the compressor.

Furthermore, the value of the stationary blade outlet angle of the compressor decreases step by step in the direction of increasing gas temperature.

Furthermore, the inlet angle values of the stator blades of each stage of the compressor are dispersedly arranged in the range of 40 to 50 degrees.

Furthermore, the stationary blades of each stage are all curved.

Furthermore, the stator blade bending circumferential stacking Rtheta off 50% span is set to -20 to -26.

The use of bending characteristics can effectively control the low-speed flow in the corner area of the stator blades. During the design process, the unit selected a suitable bending law based on the flow characteristics of each stage of stator blades to maximize the control of the corner area flow of each stage of stator blades and improve the working range of the compressor to the greatest extent.

Further, the circumferential stacking Rtheta off 50% span of the first stage stationary blades is less than the circumferential stacking Rtheta off 50% span parameter of the last stage stationary blades; and/or, the circumferential stacking Rtheta off 50% span of the first stage stationary blades is greater than the circumferential stacking Rtheta off 50% span of the second stage stationary blades. Circumferential stacking of Rtheta off 50% span parameters.

Furthermore, the aspect ratio of the moving blades is 1.2±0.1, and the aspect ratio of the stationary blades is 1.66-1.28.

A wide chord length design is adopted to further reduce the blade load and weaken the possibility and strength of boundary layer separation on the blade surface, thereby improving compressor efficiency and widening the operating range.

Furthermore, the compressor load coefficient distribution range is 0.17 to 0.28.

Furthermore, the load coefficient of the compressor first increases step by step and then decreases step by step from the primary stage to the final stage of the compressor; and/or, the load coefficient of the primary stage of the compressor is smaller than the load coefficient of the final stage of the compressor.

Due to the high design temperature, the yield strength of the material is reduced, and the allowable linear speed of the compressor design wheel shaft and blade tip is reduced, so the selected value of the compressor load factor is reduced. The higher the load factor, the fewer the stages, the greater the load of the single-stage compressor, but it is more difficult to improve efficiency and expand the working range.

Furthermore, the reaction degree distribution interval of the compressor from the second stage is 0.58 to 0.75.

Ensure that the loads of the moving blades and the stationary blades are properly distributed, maximizing efficiency while ensuring the working range. Since the first stage contains IGV, the value is not valuable, so start from the second stage.

Furthermore, the reaction degree value increases step by step from the second stage of the compressor to the last stage of the compressor.

Furthermore, the stage pressure ratio of the compressor is between 1.02 and 1.09.

Furthermore, the stage pressure ratio value of the compressor first increases step by step and then decreases step by step from the primary stage to the final stage of the compressor; and/or, the primary stage pressure ratio value is smaller than the final stage pressure ratio value.

The pressure ratio of the first few stages is slightly lower to reduce the Mach number as much as possible, thereby widening the operating range; the pressure ratio of the subsequent stages is also gradually reduced, thereby weakening the disadvantage of the boundary layer thickening stage by stage, reducing the possibility of separation in the subsequent stages and improving efficiency.

Furthermore, the compressor air inlet and the compressor exhaust port are arranged in the radial direction of the main shaft, that is, the axial directions of the compressor air inlet and the compressor exhaust port are both 90° to the axis of the main shaft in the compressor.

Furthermore, the rotor assembly also includes a wheel axle, the main shaft in the compressor is composed of multiple wheel axles connected end to end, and the moving blades are fixedly connected to the circumferential surface of the wheel axle; a pull rod is passed through the multiple wheel axles, one end of the pull rod is threadedly connected to a nut, and the multiple wheel axles are locked by the nuts.

Furthermore, at least one level of moving blades is provided on each level of the wheel shaft; wherein the number of moving blades installed on the lower level wheel shaft along the gas movement direction is not less than the number of moving blades installed on the upper level wheel shaft.

Furthermore, two end surfaces of adjacent wheel axles that are close to each other are respectively provided with connecting parts, and the adjacent wheel axles are connected through the connecting parts.

Furthermore, the connecting portion is an end tooth provided on the end face of the wheel shaft, and the end teeth on the two adjacent end faces of the wheel shaft are End teeth meshing.

Furthermore, the stator assembly also includes an inner cylinder, the inner surface of which is provided with an annular groove with an I-shaped cross-section; a guide vane is fixedly connected in the annular groove closest to the compressor air inlet, and stationary blades are fixedly connected in the remaining annular grooves, and the stationary blades are spaced apart from the moving blades.

Furthermore, the guide vane includes a guide blade and a guide vane root, and the guide vane root is fixedly arranged in the annular groove along its circumference; the length direction of the guide vane root is the same as the axial direction of the inner cylinder.

Furthermore, the stator blades include stator blades and stator blade roots, the stator blade roots are fixedly arranged in the annular groove along the circumference thereof; the length direction of the stator blade roots is inclined relative to the axial direction of the inner cylinder; the circumferential spacing between the stator blades of the same stage is the same, and the circumferential spacing between the stator blades of different stages gradually decreases along the airflow direction.

Furthermore, a compressor channel is formed between the inner cylinder and the wheel axle, and the compressor channel is set to any one of equal outer diameter, equal inner diameter and equal median diameter.

Furthermore, a thrust bearing and a radial bearing are provided on the main shaft in the compressor, an air intake cavity is provided between the compressor air inlet and the compressor channel, an air exhaust cavity is provided between the compressor exhaust port and the compressor channel, the space where the thrust bearing is located and the air intake cavity, and the space where the radial bearing is located and the air exhaust cavity are isolated from each other by shaft end seals, respectively, and the thrust bearing and the radial bearing are located outside the air flow channel formed by the air intake cavity, the compressor channel and the air exhaust cavity.

Furthermore, the shaft end seal is configured as a labyrinth seal structure, and cooling sealing gas is injected into the shaft end seal, and the cooling sealing gas is air.

Furthermore, it also includes an expander casing, and the compressor casing and the expander casing are connected by bolts.

Furthermore, it also includes a compressor base, on which are provided several groups of support assemblies, including one group of fixed support assemblies and two groups of swing support assemblies; the fixed support assembly is located in the middle of the compressor base and is fixedly connected to the compressor casing, and the two groups of swing support assemblies are respectively located on both sides of the compressor base and are respectively movably connected to the compressor casing.

The present invention also provides a high-temperature heat pump energy storage system, comprising a compression expansion unit for a high-temperature heat pump, a heat source circulation supply system and an energy storage device.

The present invention has the following beneficial effects:

1. The present invention is aimed at the high-temperature working condition of the compressor. Since the intake temperature of the compressor is relatively high, some bearing parts and lubricating oil cannot work under high-temperature working conditions. Therefore, a radial air intake method is adopted to design the bearings and the like outside the air flow channel formed by the intake cavity, the compressor channel and the exhaust cavity, thereby isolating the bearing area from the high-temperature intake area, so that the bearing can avoid high-temperature working conditions. At the same time, cooling sealing gas is added to the shaft end seal to isolate the high-temperature gas from entering the bearing area while cooling the shaft end. At this time, the use of conventional bearing materials can meet the safe and reliable operation of the compressor under high-temperature working conditions.

2. By rationally arranging the intake and exhaust modes, optimizing the aerodynamic design of the guide vanes, stationary vanes and moving vanes, selecting appropriate inlet and outlet angles, and optimizing the blade row spacing, the working efficiency of the compressor is improved, the stable operation of the compressor is maintained, and the safe and efficient operation of the compressor under high temperature conditions is further ensured.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a high temperature heat pump energy storage system of the present invention;

FIG2 is a schematic diagram of the structure of a compression expansion unit in Example 1 of the present invention;

FIG3 is a cross-sectional view of the compressor in Embodiment 1 of the present invention;

FIG4 is a schematic diagram of the positional relationship of the support components in Embodiment 2 of the present invention;

FIG5 is a schematic diagram of the structure of the wheel axle in Embodiment 1 of the present invention;

FIG6 is a schematic diagram of the structure of the guide vane in Embodiment 1 of the present invention;

FIG7 is a schematic diagram of the structure of the inner cylinder in Embodiment 1 of the present invention;

FIG8 is a schematic diagram of the circumferential stacking Rtheta off 50% span of the stator blade bending in Example 1 of the present invention;

FIG9 is a schematic diagram of the blade row spacing in Example 1 of the present invention;

FIG10 is a schematic diagram of a distribution range of reaction degree of a compressor in Embodiment 1 of the present invention;

FIG11 is a schematic diagram of a load coefficient distribution interval of a compressor in Embodiment 1 of the present invention;

FIG12 is a schematic diagram of the stage pressure ratio distribution range of the compressor in Example 1 of the present invention;

FIG13 is a schematic diagram of the structure of the stationary blade locking group in Example 3 of the present invention.

In the above drawings: 1. compressor casing; 2. compressor base; 3. compressor air inlet; 4. compressor exhaust port; 5. inner cylinder; 6. ring groove; 7. guide vane; 8. stationary vane; 9. axle; 10. tie rod; 11. compressor channel; 12. baffle; 13. thrust bearing; 14. radial bearing; 15. air inlet chamber; 16. exhaust chamber; 17. first sealing air duct; 18. second sealing air duct; 19. end teeth; 20. fixed support assembly; 21. swing support assembly; 22. center dividing surface of cylinder body; 23. stationary vane of center dividing surface; 24. cutting angle plane; 25. moving vane.

DETAILED DESCRIPTION

The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

Example 1

A compression expansion unit for a high-temperature heat pump includes a multi-stage axial flow compressor and an axial flow expander. The compressor is an air compressor, which compresses air from high temperature and normal pressure to about 0.6MPa and 400℃, and has the characteristics of large flow, high pressure ratio, high temperature, frequent variable working condition adjustment, and frequent start and stop; the expander is an air expander, which is used to expand air from normal temperature and high pressure air to low temperature and normal pressure air to generate cooling capacity, and is coaxially connected with the air compressor to offset part of the compressor power consumption, and has large flow, large Characteristics of expansion ratio, low temperature, frequent adjustment of variable operating conditions, and frequent start and stop.

As shown in Fig. 2 and Fig. 3, the compressor includes a rotor assembly, a stator assembly and a housing assembly. The housing assembly includes a compressor casing 1, on which a compressor air inlet 3 and a compressor exhaust port 4 are provided. The axial directions of the compressor air inlet 3 and the compressor exhaust port 4 are respectively N° and M° with the axis of the main shaft in the compressor, wherein 0＜N＜180, 0＜M＜180. In this embodiment, the directions of the air inlet and the exhaust port are preferably arranged along the radial direction of the main shaft, that is, the axial directions of the compressor air inlet 3 and the compressor exhaust port 4 are both 90° with the axis of the main shaft in the compressor.

The stator assembly is used to convert the kinetic energy of the gas into pressure energy and adjust the gas flow direction. As shown in Figures 3 and 7, the stator assembly includes an inner cylinder 5, which is located inside the outer shell assembly. The inner cylinder 5 is formed by combining the upper cylinder body and the lower cylinder body, and a plurality of annular grooves 6 with an I-shaped cross section are provided on the inner surface of the inner cylinder 5. A guide vane 7 is fixedly connected in the annular groove 6 closest to the compressor air inlet 3, and multiple stages of stationary vanes 8 are fixedly connected in the remaining annular grooves 6.

Among them, the guide vane 7 includes a guide vane and a guide vane root. The guide vane root is fixedly arranged along the circumference of the annular groove 6, and the length direction of the guide vane root is the same as the axial direction of the inner cylinder 5. The guide vane is a three-dimensional twisted blade, which provides pre-rotation for the next stage of blades by changing the flow state of the gas. The inlet angle of the guide vane 7 is set to 0°, and the outlet angle of the guide vane 7 is set to 35°. As shown in Figure 6, the stator 8 includes a stator blade and a stator root. The stator blade is a three-dimensional twisted blade, that is, it is curved. The stator 8 uses a three-dimensional twisted blade to effectively control the low-speed flow in the corner area of the stator 8. Based on the flow characteristics of each stage of the stator 8, a suitable bending law is selected to maximize the control of the corner area flow of each stage of the stator 8, which improves the working range of the compressor to the greatest extent. The stator root is fixedly arranged along the circumference of the annular groove 6; the length direction of the stator root is inclined relative to the axial direction of the inner cylinder 5. Among them, the inlet angle of the stator blade 8 is set to 40-50°, and the inlet angle values of the stator blades 8 of each stage are dispersed in the range of 40-50°; the outlet angle of the stator blade 8 is set to 10-30°, and the outlet angle values of the stator blade 8 are gradually reduced along the direction of increasing gas temperature. The axial spacing between the stator blades 8 of the same stage is the same, and the circumferential spacing between the stator blades 8 of different stages along the airflow direction gradually decreases. The gas is decelerated, pressurized, and heated in the flow channel of the stator blade 8, that is, the velocity energy is converted into pressure energy and heat energy. The aspect ratio of the stator blades 8 of each stage is in the range of 1.28-1.66. As shown in Figure 8, the bending circumferential stack Rtheta off 50% span of the stator blade 8 is set to between -20 and -26. The circumferential overlap Rtheta off 50% span of the first-stage stator blades 8 is smaller than the circumferential overlap Rtheta off 50% span parameter of the last-stage stator blades 8; the circumferential overlap Rtheta off 50% span of the first-stage stator blades 8 is greater than the circumferential overlap Rtheta off 50% span parameter of the second-stage stator blades 8.

The rotor assembly is used to give kinetic energy to the gas compressor channel 11 and drive the gas to move axially inside the compressor. The rotor assembly is located in the internal space of the inner cylinder 5, and includes multiple axles 9, which are connected end to end, and a common tie rod 10 is passed through the multiple axles 9 to form the main shaft of the compressor, which is driven to rotate by a motor. The compressor channel 11 is formed between the inner cylinder 5 and the axle 9, and can be set to any one of equal outer diameter, equal inner diameter and equal median diameter. Among them, The equal outer diameter is set to the inner diameter of the inner cylinder 5 unchanged along the airflow direction, and the equal inner diameter is set to the outer diameter of the axle 9 unchanged along the airflow direction. In this embodiment, the compressor channel 11 is set to a constant middle diameter structure, that is, the inner diameter of the inner cylinder 5 gradually decreases along the airflow direction, while the outer diameter of the axle 9 gradually increases along the airflow direction.

The circumferential surfaces of the multiple wheel shafts 9 are also fixed with moving blades 25 along the circumferential direction thereof, thereby forming a multi-stage moving blade structure, and the number of moving blades installed on the lower wheel shaft along the gas moving direction in the compressor is not less than the number of moving blades installed on the upper wheel shaft. The blades of the next stage of the guide vane 7 are the moving blades 25, and the blades of the next stage of the moving blades 25 are the stationary blades 8. The moving blades 25 are three-dimensional twisted blades, and the inlet angle of the moving blades 25 is set to -55 to 65°, and the outlet angle of the moving blades 25 is set to -45 to -55°. In the multi-stage moving blade structure, the outlet angle value of the moving blades 25 of the compressor first increases step by step and then decreases step by step in the direction of the gas temperature increase, and the outlet angle value of the primary moving blades 25 of the compressor is greater than the outlet angle value of the last moving blades 25 of the compressor. The inlet angle value of the moving blades 25 of the compressor first increases step by step and then decreases step by step in the direction of the gas temperature increase; and the inlet angle value of the primary moving blades 25 of the compressor is greater than the inlet angle value of the last moving blades 25 of the compressor. The aspect ratio of the moving blade 25 is set to 1.2, and a wide chord length design is adopted to further reduce the blade load, reduce the possibility and strength of the boundary layer separation on the blade surface, thereby improving the compressor efficiency and widening the working range. As shown in Figure 11, the compressor load coefficient distribution range is 0.17-0.28, and the compressor load coefficient first increases step by step and then decreases step by step from the primary stage of the compressor to the final stage of the compressor. The primary load coefficient of the compressor is less than the final load coefficient of the compressor. As shown in Figure 10, the compressor reaction degree distribution range from the second stage is 0.58-0.75, and the reaction degree value increases step by step from the second stage of the compressor to the final stage of the compressor. As shown in Figure 12, the compressor stage pressure ratio value is 1.02-1.09, and the compressor stage pressure ratio value first increases step by step and then decreases step by step from the primary stage of the compressor to the final stage of the compressor. The primary stage pressure ratio value is less than the final stage pressure ratio value.

The moving blades 25 and the stationary blades 8 are spaced apart, as shown in FIG9 , and the blade row spacing of the moving blades 25 and the stationary blades 8 is set to 9 to 35 mm and gradually decreases along the airflow direction. Under high-temperature working conditions, the thermal expansion of the moving blades 25 and the stationary blades 8 is greater than that of conventional industrial compressors. During the design process, the distance between the blade rows must be set based on the accurate expansion difference to ensure that the moving blades 25 and the stationary blades 8 will not collide with each other under any working condition of the unit. The large spacing between the blade rows will affect the working range of the compressor. Therefore, the design of this blade row spacing ensures both the safety of operation and the performance and working range. A balancing disk is set behind the last-stage blades, and a balancing disk seal is configured to further balance the axial thrust and reduce gas leakage. In this embodiment, the aerodynamic design features are as follows: the consistency of the moving blades 25 is about 1, the stationary blades 8 are designed with a large consistency and a high aspect ratio, the stage pressure ratio distribution has a gradually increasing front stage pressure ratio, a middle stage pressure ratio of 1.16 is the highest, and a final stage pressure ratio gradually decreases, and the reaction degree increases step by step, so that the airflow in the compressor flow channel is more stable, reducing the risk of flow field deterioration caused by air flow loss, which is beneficial to improving the efficiency of the compressor and increasing the stable operating range of the compressor.

A baffle 12 is provided in the casing opposite to the air inlet. The high-temperature gas enters the compressor through the radial air inlet, hits the baffle 12, and then flows back to the inlet of the inner cylinder 5. At this time, due to the high-speed rotation of the moving blades 25, the high-temperature gas is sucked into the compressor. When it reaches the guide vane 7, it forms pre-swirl after passing through the guide vane, then it passes through the moving blade 25 to increase speed, passes through the stationary blade 8 to increase pressure and temperature, and when it flows through the exhaust port, it becomes high-temperature and high-pressure gas.

A thrust bearing 13 and a radial bearing 14 are provided on the main shaft. Specifically, a thrust bearing 13 is provided at the end of the low-pressure side of the main shaft to balance part of the thrust on the high-pressure side, and a radial bearing 14 is provided at the end of the high-pressure side to meet the requirements of high-speed operation of the main shaft. An air intake cavity 15 is provided between the compressor air intake port 3 and the compressor channel 11, and an air discharge cavity 16 is provided between the compressor air discharge port 4 and the compressor channel 11. The space where the thrust bearing 13 is located and the air intake cavity 15, and the space where the radial bearing 14 is located and the air discharge cavity 16 are isolated from each other by shaft end seals, respectively. The thrust bearing 13 and the radial bearing 14 are located outside the air flow channel formed by the air intake cavity 15, the compressor channel 11 and the air discharge cavity 16. The shaft end seal is configured as a labyrinth seal structure, and a first sealing air duct 17 and a second sealing air duct 18 are respectively provided on both sides of the compressor casing 1. The first sealing air duct 17 and the second sealing air duct 18 are respectively connected to the two shaft end seals. The shaft end seals are injected with cooling sealing air through the first sealing air duct 17 and the second sealing air duct 18 to further isolate the high temperature inside the compressor and reduce the leakage of high temperature gas to the other side of the thrust bearing 13 and the radial bearing 14.

The compression expansion unit for high temperature heat pump in this embodiment also includes an expander casing. The compressor casing 1 and the expander casing are connected by bolts and the two are internally connected. The expander includes a rotating shaft, and the same pull rod 10 is passed through the wheel shaft 9 of the compressor and the rotating shaft of the expander, so that the compressor and the expander share the same main shaft, and a nut is threaded on the pull rod 10, and multiple wheel shafts 9 are locked by nuts. A connecting part is provided between adjacent wheel shafts 9 and between the wheel shaft 9 and the rotating shaft of the expander, and transmission is carried out through the connecting part. As shown in Figure 5, in this embodiment, the connecting part is provided with an end tooth 19 provided on the end face of the wheel shaft 9 and the rotating shaft, and adjacent end teeth 19 are meshed for transmission. A conical shaft head is provided at one end of the main shaft to ensure that the torque is safely and stably transmitted to the compressor. The present application simplifies the structural design of the compression expansion unit and can effectively reduce the loss of unit efficiency. The expander casing is directly connected to the compressor casing 1 by bolts, and there is no need to design a separate support structure for the expander, so that the expander can be axially displaced with the thermal expansion of the compressor.

As shown in Figure 1, this embodiment also provides a high-temperature heat pump energy storage system, including a heat source circulation supply system, an energy storage device and the above-mentioned compression expansion unit for high-temperature heat pump, and also includes a steam circulation system. Among them, the heat source circulation supply system is used to provide hot air, including using an electric heater to heat the water in the cold water tank into hot water, and transporting it in the thermal simulation circulation pipeline through a circulating water pump, and generating hot air after absorbing heat through an air heat absorption cooler; the high-temperature heat pump cycle of the compression expansion unit for the high-temperature heat pump is the main system cycle; the energy storage device is a pressurized solid energy storage device, which is an efficient and low-cost energy storage device that takes into account both heat exchange and heat storage functions; the steam circulation system is used to absorb the heat produced in the high-temperature heat pump and stored in the solid energy storage device, and generate steam.

Example 2

As shown in FIG. 4 , this embodiment further includes a compressor base 2 . Since the compressor casing 1 and the expander casing are connected as a whole through bolts, the expander can perform axial displacement as the compressor expands thermally.

Three groups of support components are provided on the compressor base 2, including a group of fixed support components 20 and two groups of swing support components 21. One group of fixed support components 20 is located in the middle of the compressor base 2, and the two groups of swing support components 21 are respectively located on both sides of the fixed support components 20, and are also located on both sides of the compressor base 2. Each group of support components includes two support points, that is, the compressor in this embodiment adopts a six-point support method: fixed installation is adopted at two positions in the middle of the compressor base 2, and the fixed support component 20 includes two first fixed blocks fixed in the middle of the compressor base 2, and the two first fixed blocks are arranged along the width direction of the compressor, and the first fixed blocks are fixed to the middle position of the compressor casing 1 by bolts; the swing support component 21 includes a second fixed block and a swing rod, and the second fixed blocks are respectively arranged at the two sides of the two first fixed blocks on the compressor base 2, and the swing rod is fixedly arranged on the second fixed block, and four slide grooves are arranged at the bottom of the compressor casing 1, and the other end of the swing rod is slidably connected in the slide groove. When the compressor casing 1 is deformed, the swing rod slides to adapt to the deformation of the compressor casing 1. After the compressor heats up, it can expand to both sides due to the existence of the swing support assembly 21, thereby solving the deformation and stress problems caused by the thermal expansion of the compressor; by setting two sets of swing support assemblies 21, the movement deformation of a single set of swing support assemblies 21 can also be reduced, making the support structure safer and more stable. The normal temperature intake of a conventional compressor has a lower temperature in the primary corresponding section, and the thermal expansion is small, and it will not accumulate in large quantities along the axial direction toward the swing point. However, the intake of the compressor of the invention is high temperature, and the primary corresponding section will have a large thermal expansion during the operation of the compressor section for a period of time. If the end fixed support solution in the prior art is adopted, the heat conduction expansion will accumulate along the axial direction toward the swing support point. Due to the large axial length, material factors, etc., the compressor casing, base, etc. will be deformed and damaged, and the compressor cannot meet the use requirements.

Example 3

As shown in FIG13 , in this embodiment, the stator assembly further includes a stationary blade locking group structure. The stationary blade locking group structure includes a stationary blade 8 and an annular groove 6 with an I-shaped cross section provided on the inner surface of the inner cylinder 5, and also includes a center-split stationary blade 23 and a locking screw. The blade root of the stationary blade 8 is fixedly provided in the annular groove 6, and the circumferential spacing between adjacent stationary blades 8 is limited by the width of the blade root itself.

The inner cylinder 5 is formed by the combination of the upper cylinder body and the lower cylinder body, and there is a cylinder body center dividing surface 22 at the contact point between the upper cylinder body and the lower cylinder body. A center dividing surface stationary blade 23 is provided in the annular groove 6 at the cylinder body center dividing surface 22, and the blade root of the center dividing surface stationary blade 23 is set with an angle cut, that is, a cutting angle plane 24 parallel to the cylinder body center dividing surface 22 is set at the blade root of the center dividing surface stationary blade 23 to solve the problem of interference between the blade root and the inner cylinder 5 caused by the angle of the center dividing surface stationary blade 23 during assembly. A locking screw is also installed on the cutting angle plane 24 of the center dividing surface stationary blade 23 to fix the center dividing surface stationary blade 23 and the inner cylinder 5 to ensure that the stationary blade in the upper cylinder body will not slide out and fall along the annular groove 6 when the inner cylinder 5 is assembled.

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. The embodiments describe the present invention in detail. Those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the present invention, which should be included in the scope of the claims of the present invention.

Claims (29)

A compression expansion unit for a high-temperature heat pump, characterized in that it comprises a multi-stage axial flow compressor and an axial flow expander, wherein the rotating shafts of the compressor and the expander run coaxially; Wherein, the compressor comprises a rotor assembly, a stator assembly and a housing assembly; A rotor assembly is used to impart kinetic energy to the gas and drive the gas to move along its axial direction inside the compressor; the rotor assembly comprises a multi-stage moving blade (25), the inlet angle of the moving blade (25) is set to -55 to 65 degrees, and the outlet angle of the moving blade (25) is set to -45 to -55 degrees; A stator assembly is used to convert the kinetic energy of the gas into pressure energy and adjust the gas flow direction; the stator assembly comprises a guide vane (7) and a multi-stage stationary vane (8); the inlet angle of the stationary vane (8) is set to 40-50°, and the outlet angle of the stationary vane (8) is set to 10-30° and decreases step by step; the inlet angle of the guide vane (7) is set to 0°, and the outlet angle of the guide vane (7) is set to 30-40°; the blade row spacing value of the moving blade (25) and the stationary blade (8) is set to 9-35 mm, and the value decreases step by step; The housing assembly comprises a compressor casing (1), wherein a compressor air inlet (3) and a compressor exhaust port (4) are provided on the compressor casing (1), wherein the axial directions of the compressor air inlet (3) and the compressor exhaust port (4) are respectively N° and M° with the axial direction of the main shaft in the compressor, wherein 0＜N＜180, 0＜M＜180. A compression expansion unit for a high-temperature heat pump according to claim 1, characterized in that the outlet angle value of the moving blade (25) of the compressor first increases step by step and then decreases step by step along the direction of increasing gas temperature; And/or the outlet angle value of the primary moving blade (25) of the compressor is greater than the outlet angle value of the final moving blade (25) of the compressor. A compression expansion unit for a high-temperature heat pump according to claim 1, characterized in that the inlet angle value of the moving blade (25) of the compressor first increases step by step and then decreases step by step along the direction of increasing gas temperature; And/or the inlet angle value of the primary moving blade (25) of the compressor is greater than the inlet angle value of the final moving blade (25) of the compressor. A compression expansion unit for a high-temperature heat pump according to claim 1, characterized in that the outlet angle value of the stationary blade (8) of the compressor decreases step by step in the direction of increasing gas temperature. A compression expansion unit for a high-temperature heat pump according to claim 1, characterized in that the inlet angle values of the stator blades (8) of each stage of the compressor are dispersedly arranged in the range of 40 to 50 degrees. A compression expansion unit for a high-temperature heat pump according to claim 1, characterized in that the stationary blades (8) of each stage are curved. A compression expansion unit for a high-temperature heat pump according to claim 6, characterized in that the bending circumferential stack Rtheta off 50% span of the stationary blade (8) is set to -20 to -26. A compression expansion unit for a high-temperature heat pump according to claim 7, characterized in that the circumferential overlap Rtheta off 50% span of the first-stage stator blades (8) is smaller than the circumferential overlap Rtheta off 50% span parameter of the last-stage stator blades (8); and/or the circumferential overlap Rtheta off 50% span of the first-stage stator blades (8) is larger than the circumferential overlap Rtheta off 50% span parameter of the second-stage stator blades (8). A compression expansion unit for a high-temperature heat pump according to claim 1, characterized in that the aspect ratio of the moving blades (25) is 1.2±0.1, and the aspect ratio of the stationary blades (8) is 1.28-1.66. According to the compression expansion unit for a high-temperature heat pump as described in claim 1, it is characterized in that the compressor load coefficient distribution range is 0.17 to 0.28. A compression expansion unit for a high-temperature heat pump according to claim 10, characterized in that the load coefficient of the compressor first increases step by step and then decreases step by step from the primary stage of the compressor to the final stage of the compressor; And/or, the primary load factor of the compressor is smaller than the final load factor of the compressor. A compression expansion unit for a high-temperature heat pump according to claim 1, characterized in that the reaction degree distribution range of the compressor from the second stage is 0.58 to 0.75. A compression expansion unit for a high-temperature heat pump according to claim 12, characterized in that the reaction degree value increases step by step from the second stage of the compressor to the last stage of the compressor. The compression expansion unit for a high-temperature heat pump according to claim 1 is characterized in that the stage pressure ratio of the compressor is 1.02 to 1.09. A compression expansion unit for a high-temperature heat pump according to claim 14, characterized in that the stage pressure ratio value of the compressor first increases step by step and then decreases step by step from the primary stage of the compressor to the final stage of the compressor; And/or, the primary stage pressure ratio value is smaller than the final stage pressure ratio value. According to a compression expansion unit for a high-temperature heat pump as described in claim 1, it is characterized in that the directions of the compressor air inlet (3) and the compressor exhaust port (4) are arranged along the radial direction of the main shaft, that is, the axial directions of the compressor air inlet (3) and the compressor exhaust port (4) are both 90° to the axis of the main shaft in the compressor. According to a compression expansion unit for a high-temperature heat pump as described in claim 1, it is characterized in that the rotor assembly also includes a wheel shaft (9), the main shaft in the compressor is composed of multiple wheel shafts (9) connected end to end, and the moving blades (25) are fixedly connected to the circumferential surface of the wheel shaft (9); multiple pull rods (10) are passed through the multiple wheel shafts (9), one end of the pull rod (10) is threadedly connected with a nut, and the multiple wheel shafts (9) are locked by the nut. A compression expansion unit for a high-temperature heat pump according to claim 17, characterized in that at least one stage of moving blades is provided on each stage of the wheel shaft; Among them, the number of moving blades installed on the lower wheel shaft along the gas movement direction is not less than the number of moving blades installed on the upper wheel shaft. According to a compression expansion unit for a high-temperature heat pump according to claim 17, it is characterized in that connecting parts are respectively provided on two end surfaces close to adjacent axles (9), and adjacent axles (9) are connected by the connecting parts. According to a compression expansion unit for a high-temperature heat pump as described in claim 19, it is characterized in that the connecting portion is an end tooth (19) provided on the end face of the axle (9), and the end teeth (19) on the two end faces adjacent to the axle (9) are meshed. According to a compression expansion unit for a high-temperature heat pump as described in claim 17, it is characterized in that the stator assembly also includes an inner cylinder (5), the inner surface of the inner cylinder (5) is provided with an annular groove (6) with an I-shaped cross-section; a guide vane (7) is fixedly connected in the annular groove (6) closest to the compressor air inlet (3), and stationary blades (8) are fixedly connected in the remaining annular grooves (6), and the stationary blades (8) are spaced apart from the moving blades (25). According to a compression expansion unit for a high-temperature heat pump according to claim 21, it is characterized in that the guide vane (7) includes a guide blade and a guide vane root, and the guide vane root is fixedly arranged in the annular groove (6) along its circumference; the length direction of the guide vane root is the same as the axial direction of the inner cylinder (5). According to a compression expansion unit for a high-temperature heat pump as described in claim 21, it is characterized in that the stator blade (8) includes a stator blade and a stator blade root, and the stator blade root is fixedly arranged in the annular groove (6) along its circumference; the length direction of the stator blade root is inclined relative to the axial direction of the inner cylinder (5); the circumferential spacing between the stator blades (8) of the same stage is the same, and the circumferential spacing between the stator blades (8) of different stages along the airflow direction gradually decreases. A compression expansion unit for a high-temperature heat pump according to claim 21, characterized in that a compressor channel (11) is formed between the inner cylinder (5) and the axle (9), and the compressor channel (11) is set to any one of equal outer diameter, equal inner diameter and equal middle diameter. A compression expansion unit for a high-temperature heat pump according to claim 24, characterized in that a thrust bearing (13) and a radial bearing (14) are provided on the main shaft inside the compressor, an air intake chamber (15) is provided between the compressor air inlet (3) and the compressor channel (11), an air exhaust chamber (16) is provided between the compressor air exhaust (4) and the compressor channel (11), the space where the thrust bearing (13) is located and the air intake chamber (15), and the space where the radial bearing (14) is located and the air exhaust chamber (16) are isolated from each other by shaft end seals, respectively, and the thrust bearing (13) and the radial bearing (14) are located outside the air flow channel formed by the air intake chamber (15), the compressor channel (11) and the air exhaust chamber (16). According to a compression expansion unit for a high-temperature heat pump according to claim 25, it is characterized in that the shaft end seal is set as a labyrinth seal structure, the shaft end seal is injected with cooling sealing gas, and the cooling sealing gas is air. The compression expansion unit for a high-temperature heat pump according to claim 1 is characterized in that it also includes an expander casing, and the compressor casing (1) and the expander casing are connected by bolts. According to claim 27, a compression expansion unit for a high-temperature heat pump is characterized in that it also includes a compressor base (2), and the compressor base (2) is provided with a plurality of support components, including a group of fixed support components (20) and two groups of swing support components (21); the fixed support component (20) is located in the middle of the compressor base (2) and is fixedly connected to the compressor casing (1), and the two groups of swing support components (21) are respectively located on both sides of the compressor base (2) and are respectively movably connected to the compressor casing (1). A high-temperature heat pump energy storage system, characterized in that it includes a compression expansion unit for a high-temperature heat pump according to any one of claims 1-28, and also includes a heat source circulation supply system and an energy storage device.