Supercritical carbon dioxide compression cooling system

Abstract

The present invention relates to the technical field of supercritical carbon dioxide circulation system, and discloses a supercritical carbon dioxide compression cooling system, comprising a turbine, a supercritical carbon dioxide cooler, a compressor and a heat exchanger connected in sequence, wherein the compressor comprises a housing chamber for accommodating a compression mechanism and a motor and a compressor cooling mechanism arranged outside the housing chamber; the compressor cooling mechanism comprises a refrigerant channel surrounding the housing chamber, the inlet of the refrigerant channel is connected to the outlet of the supercritical carbon dioxide cooler, and the outlet of the refrigerant channel is connected to the inlet of the compressor. The supercritical carbon dioxide compression cooling system guides a portion of the low-temperature supercritical carbon dioxide at the outlet of the supercritical carbon dioxide cooler to the compressor cooling mechanism to cool the compression mechanism and the motor, thereby avoiding the technical problems of reduced motor reliability and shortened service life due to erosion corrosion caused by the use of liquid water.

Description

Technical Field

[0001] The invention relates to the technical field of supercritical carbon dioxide circulation systems, and in particular to a supercritical carbon dioxide compression cooling system. Background Art

[0002] During the energy conversion process, the rotating motor will also generate losses. The existence of losses directly affects the efficiency and economical operation of the motor. On the other hand, since the lost energy is finally converted into heat energy, the temperature of various parts of the motor will rise, which will directly affect the life of the insulation material used in the motor and limit the output of the motor. In severe cases, the motor may be burned. Therefore, on the one hand, attention should be paid to reasonably reducing the losses of the motor during design, and on the other hand, efforts should be made to improve the cooling conditions so that the heat can be effectively dissipated as soon as possible.

[0003] Currently, electric compressor motor cooling is generally achieved through water cooling or air cooling technology. The motor of the supercritical carbon dioxide compressor has a high speed and high thermal power. Due to the low air heat exchange coefficient, traditional air cooling technology is difficult to achieve effective cooling of the supercritical carbon dioxide compressor motor. Since the temperature rise of the cooling water is limited by boiling conditions, the use of traditional water cooling technology requires a large amount of cooling water. Too fast a flow rate will cause erosion and corrosion of the motor cooling water channel, reduce the reliability of the motor, and affect the service life of the motor. Summary of the invention

[0004] The embodiment of the present invention provides a supercritical carbon dioxide compression cooling system to solve the problems of large amount of water cooling technology, fast flow rate and easy erosion and corrosion of flow channel, so as to improve the reliability of the motor.

[0005] An embodiment of the present invention provides a supercritical carbon dioxide compression cooling system, including a supercritical carbon dioxide circulation loop, wherein the supercritical carbon dioxide circulation loop includes a turbine, a supercritical carbon dioxide cooler, a compressor and a heat exchanger connected in sequence, wherein the compressor includes a housing chamber for accommodating a compression mechanism and an electric motor, and a compressor cooling mechanism arranged outside the housing chamber; the compressor cooling mechanism includes a refrigerant channel surrounding the housing chamber, the inlet of the refrigerant channel is connected to the outlet of the supercritical carbon dioxide cooler, and the outlet of the refrigerant channel is connected to the inlet of the compressor.

[0006] Wherein, the refrigerant channel includes a stator heat dissipation channel and a compression chamber heat dissipation channel which are interconnected, the stator heat dissipation channel is arranged around the outside of the motor stator, and the compression chamber heat dissipation channel is arranged around the outside of the compression chamber.

[0007] Wherein, the refrigerant channel also includes an end heat dissipation channel arranged at the rear end of the motor, and the end heat dissipation channel, the stator heat dissipation channel and the compression chamber heat dissipation channel are interconnected; a plurality of heat dissipation fins are arranged on the outer side of the end heat dissipation channel.

[0008] Wherein, the compressor cooling mechanism also includes a heat dissipation fan arranged on the outer side of the end heat dissipation channel, and the heat dissipation fan is coaxially sleeved on the rotating shaft of the motor.

[0009] The inlet of the refrigerant channel is connected to the outlet of the supercritical carbon dioxide cooler through a cooling pipeline, and a regulating valve is installed on the cooling pipeline.

[0010] Wherein, a pressure sensor is also installed on the cooling pipeline.

[0011] Wherein, a flow meter is also installed on the cooling pipeline.

[0012] The supercritical carbon dioxide compression cooling system provided by the embodiment of the present invention includes a turbine, a supercritical carbon dioxide cooler, a compressor and a heat exchanger connected in sequence, the compressor includes a housing chamber for accommodating a compression mechanism and a motor and a compressor cooling mechanism arranged outside the housing chamber; the compressor cooling mechanism includes a refrigerant channel surrounding the housing chamber, the inlet of the refrigerant channel is connected to the outlet of the supercritical carbon dioxide cooler, and the outlet of the refrigerant channel is connected to the inlet of the compressor. The supercritical carbon dioxide compression cooling system guides a portion of the low-temperature supercritical carbon dioxide at the outlet of the supercritical carbon dioxide cooler to the compressor cooling mechanism to cool the compression mechanism and the motor. By utilizing the physical properties of supercritical carbon dioxide, the technical problems of reduced motor reliability and shortened service life due to erosion corrosion caused by the use of liquid water can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 is a structural schematic diagram of a supercritical carbon dioxide compression cooling system in an embodiment of the present invention;

[0015] Figure 2 yes Figure 1 A partial cross-sectional view of a compressor in FIG.

[0016] Description of reference numerals:

[0017] 1: turbine; 2: supercritical carbon dioxide cooler; 3: compressor;

[0018] 31: Electric motor; 32: Compression mechanism; 4: Heat exchanger;

[0019] 5: refrigerant channel; 51: stator heat dissipation channel; 52: compression chamber heat dissipation channel;

[0020] 53: end heat dissipation channel; 6: cooling fan; 7: cooling pipeline. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "first" and "second" are for the purpose of clearly describing the numbering of product components and do not represent any substantial difference. The directions of "up", "down", "left" and "right" are all based on the directions shown in the accompanying drawings. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0023] It should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the invention can be understood in specific circumstances.

[0024] Figure 1 is a structural schematic diagram of a supercritical carbon dioxide compression cooling system in an embodiment of the present invention, Figure 2 yes Figure 1 A partial cross-sectional view of the compressor in FIG. Figure 1-2As shown, a supercritical carbon dioxide compression cooling system provided by an embodiment of the present invention includes a supercritical carbon dioxide circulation loop, which includes a turbine 1, a supercritical carbon dioxide cooler 2, a compressor 3 and a heat exchanger 4 connected in sequence, and the compressor 3 includes a housing chamber for accommodating a compression mechanism 32 and a motor 31, and a compressor cooling mechanism arranged outside the housing chamber. The compressor cooling mechanism includes a refrigerant channel 5 surrounding the housing chamber, the inlet of the refrigerant channel 5 is connected to the outlet of the supercritical carbon dioxide cooler 2, and the outlet of the refrigerant channel 5 is connected to the inlet of the compressor 3. The first heat exchange side of the supercritical carbon dioxide cooler 2 is connected to the supercritical carbon dioxide circulation loop, and the second heat exchange side of the supercritical carbon dioxide cooler 2 is connected to the external cooling system. The first heat exchange side of the heat exchanger 4 is connected to the supercritical carbon dioxide circulation loop, and the second heat exchange side of the heat exchanger 4 is connected to an external heat source.

[0025] Specifically, the circulating medium of the supercritical carbon dioxide circulation loop and the cooling medium of the compressor cooling mechanism are both supercritical carbon dioxide. Room temperature supercritical carbon dioxide has the characteristics of high density (approximately 30%-50% of the density of room temperature liquid water), high specific heat ratio (approximately 1.5 times the specific heat ratio of room temperature liquid water), and low viscosity (approximately 1 / 30 of room temperature liquid water). Due to the low viscosity, supercritical carbon dioxide will not cause erosion and corrosion to the cooling flow channel due to excessive viscosity at high flow rates.

[0026] After the supercritical carbon dioxide enters the compressor 3 and is compressed, it enters the heat exchanger 4 to absorb heat, and then enters the turbine 1 to expand and do work. The turbine 1 is connected to the generator and then connected to the power generation system. Finally, the supercritical carbon dioxide enters the supercritical carbon dioxide cooler 2 and is cooled to the initial state point, and re-enters the compressor 3 to complete a cycle. At the same time, the outlet of the supercritical carbon dioxide cooler 2 leads to the inlet of the refrigerant channel 5, providing a part of the supercritical carbon dioxide for cooling the compressor 3. The compressor 3 includes a shell, and the interior of the shell constitutes a accommodating chamber for installing the compression mechanism 32 and the motor 31. The refrigerant channel 5 can be a flow pipe opened in the shell wall of the shell.

[0027] The present embodiment provides a supercritical carbon dioxide compression cooling system, comprising a turbine, a supercritical carbon dioxide cooler, a compressor and a heat exchanger connected in sequence, wherein the compressor comprises a housing chamber for accommodating a compression mechanism and a motor and a compressor cooling mechanism disposed outside the housing chamber; the compressor cooling mechanism comprises a refrigerant channel surrounding the housing chamber, the inlet of the refrigerant channel is connected to the outlet of the supercritical carbon dioxide cooler, and the outlet of the refrigerant channel is connected to the inlet of the compressor. The supercritical carbon dioxide compression cooling system guides a portion of the low-temperature supercritical carbon dioxide at the outlet of the supercritical carbon dioxide cooler to the compressor cooling mechanism to cool the compression mechanism and the motor, and utilizes the physical properties of supercritical carbon dioxide to avoid the technical problems of reduced motor reliability and reduced service life due to erosion corrosion caused by the use of liquid water.

[0028] Furthermore, if Figure 2 As shown, the refrigerant channel 5 includes a stator heat dissipation channel 51 and a compression chamber heat dissipation channel 52 which are interconnected. The stator heat dissipation channel 51 is arranged around the outside of the motor stator, and the compression chamber heat dissipation channel 52 is arranged around the outside of the compression chamber. Specifically, the stator heat dissipation channel 51 and the compression chamber heat dissipation channel 52 can both adopt a spiral heat dissipation channel, an annular heat dissipation channel or a squirrel cage heat dissipation channel.

[0029] Furthermore, if Figure 2 As shown, the refrigerant channel 5 also includes an end heat dissipation channel 53 disposed at the rear end of the motor 31, and the end heat dissipation channel 53, the stator heat dissipation channel 51 and the compression chamber heat dissipation channel 52 are interconnected. A plurality of heat dissipation fins are disposed on the outer side of the end heat dissipation channel 53. Specifically, the end heat dissipation channel 53 can adopt a spiral heat dissipation channel, an annular heat dissipation channel or a squirrel cage heat dissipation channel. The heat dissipation fins face the outside of the motor 31, and a plurality of heat dissipation holes are provided on the end cover at the rear end of the motor 31.

[0030] Furthermore, if Figure 2 As shown, the compressor cooling mechanism also includes a cooling fan 6 disposed outside the end cooling channel 53, and the cooling fan 6 is coaxially sleeved on the rotating shaft of the motor 31. The cooling fan 6 is driven to rotate by the rotating shaft of the motor 31, so that the heat dissipation of the rear end of the motor 31 can be enhanced.

[0031] Furthermore, the inlet of the refrigerant channel 5 is connected to the outlet of the supercritical carbon dioxide cooler 2 through a cooling pipeline 7, and a regulating valve (not shown in the figure) is installed on the cooling pipeline 7. Specifically, an electric regulating valve or a manual regulating valve can be used to adjust the pressure and flow of the supercritical carbon dioxide to the refrigerant channel 5 by adjusting the opening of the regulating valve.

[0032] Furthermore, a pressure sensor (not shown in the figure) is also installed on the cooling pipeline 7, and a flow meter (not shown in the figure) is also installed on the cooling pipeline 7, and a vortex flow meter can be used specifically. The state of the supercritical carbon dioxide in the cooling pipeline 7 can be monitored in real time by the pressure sensor and the flow meter, and the opening of the regulating valve can be adjusted in time to meet the cooling demand of the compressor 3.

[0033] It can be seen from the above embodiments that the supercritical carbon dioxide compression cooling system provided by the present invention includes a turbine, a supercritical carbon dioxide cooler, a compressor and a heat exchanger connected in sequence, the compressor includes a housing chamber for accommodating a compression mechanism and a motor and a compressor cooling mechanism arranged outside the housing chamber; the compressor cooling mechanism includes a refrigerant channel surrounding the housing chamber, the inlet of the refrigerant channel is connected to the outlet of the supercritical carbon dioxide cooler, and the outlet of the refrigerant channel is connected to the inlet of the compressor. The supercritical carbon dioxide compression cooling system guides a portion of the low-temperature supercritical carbon dioxide at the outlet of the supercritical carbon dioxide cooler to the compressor cooling mechanism to cool the compression mechanism and the motor. By utilizing the physical properties of supercritical carbon dioxide, the technical problems of reduced motor reliability and reduced service life due to erosion corrosion caused by the use of liquid water can be avoided.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A supercritical carbon dioxide compression cooling system, comprising a supercritical carbon dioxide circulation loop, wherein the supercritical carbon dioxide circulation loop comprises a turbine, a supercritical carbon dioxide cooler, a compressor and a heat exchanger connected in sequence, characterized in that: The compressor comprises a housing chamber for accommodating a compression mechanism and a motor, and a compressor cooling mechanism arranged outside the housing chamber; the compressor cooling mechanism comprises a refrigerant channel surrounding the housing chamber, the inlet of the refrigerant channel is connected to the outlet of the supercritical carbon dioxide cooler through a cooling pipeline, a regulating valve is installed on the cooling pipeline, and the outlet of the refrigerant channel is connected to the inlet of the compressor; The refrigerant channel comprises a stator heat dissipation channel and a compression chamber heat dissipation channel which are interconnected. The stator heat dissipation channel is arranged around the outside of the motor stator, and the compression chamber heat dissipation channel is arranged around the outside of the compression chamber.

2. The supercritical carbon dioxide compression cooling system according to claim 1, characterized in that: The refrigerant channel also includes an end heat dissipation channel arranged at the rear end of the motor, and the end heat dissipation channel, the stator heat dissipation channel and the compression chamber heat dissipation channel are interconnected; a plurality of heat dissipation fins are arranged on the outer side of the end heat dissipation channel.

3. The supercritical carbon dioxide compression cooling system according to claim 2, characterized in that: The compressor cooling mechanism also includes a heat dissipation fan arranged on the outer side of the end heat dissipation channel, and the heat dissipation fan is coaxially sleeved on the rotating shaft of the motor.

4. The supercritical carbon dioxide compression cooling system according to claim 1, characterized in that: A pressure sensor is also installed on the cooling pipeline.

5. The supercritical carbon dioxide compression cooling system according to claim 1, characterized in that: A flow meter is also installed on the cooling pipeline.

Images