Refrigeration unit sharing cooling water and control method thereof

Abstract

The application discloses a refrigerating unit shared by an air conditioner and a shield tunneling machine and a control method thereof. The refrigerating unit comprises a cooling tower, a heat exchanger for cooling the shield tunneling machine is arranged between the cooling tower and the refrigerating unit, a bypass is connected to two ends of the heat exchanger, a control valve is arranged on the bypass, the control method adjusts the opening degree of the bypass valve to preferentially ensure normal operation of the shield tunneling machine, adjusts the frequency conversion of a compressor according to the change of the ambient temperature, and finally adjusts the opening degree of the bypass valve according to the change of the power of the refrigerating unit before and after the adjustment of the opening degree of the bypass valve, so that the whole refrigerating unit is adjusted to run in the optimal energy consumption state. The heat exchanger for cooling the shield tunneling machine is integrated into the cooling water system of the refrigerating unit on the basis of the cold air conditioning refrigerating system, and the integration degree is high. The control method enables the refrigerating unit to stably and reliably run in the optimal energy consumption mode.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and in particular to a refrigeration unit and its control method for sharing cooling water between an air conditioner and a tunnel boring machine. Background Technology

[0002] In high-temperature mines, the rock temperature increases by 1.6-3.0℃ per 100m with increasing mining depth. When the rock temperature reaches over 40℃ at a depth of 1000 meters, the motor in the tunnel boring machine's (TBM) working area generates significant heat, leading to a substantial temperature rise and impacting worker efficiency. Simultaneously, the high-power operation causes a rapid increase in internal equipment temperature, increasing the risk of equipment malfunction. Therefore, it is necessary to cool the TBM and its working area to ensure the TBM's normal operation and a comfortable working environment for workers.

[0003] Currently, the following three methods are generally used in mines to cool down tunnel boring machines and working faces: The first method uses air-cooling units to deliver cool air to the working face through ducts to cool it down. However, because the tunnel boring machine operates on a mobile basis, the length and location of the ducts need to be constantly adjusted, which presents problems in practice and results in poor cooling effect on the working face area.

[0004] The second option involves each of the tunnel boring machine and the working face having its own cooling system. However, the integration of the two cooling systems is not high, the control is cumbersome, and the cost is very high.

[0005] The third approach involves connecting the cooling systems of the tunnel boring machine (TBM) and the air conditioning unit in series or parallel for centralized control. In a series configuration, the cooling water first passes through the TBM and then enters the condenser of the air conditioning unit. During tunneling, the average outlet temperature of the cooling water can reach over 40°C, and the temperature at the tunnel tip can even reach 50°C. This leads to excessively high return water temperature and condensation temperature, resulting in poor cooling performance of the air conditioning unit. A parallel configuration, on the other hand, can easily lead to improper distribution of cooling water and insufficient cooling water supply to the air conditioning unit.

[0006] Therefore, how to reasonably configure the equipment to meet the cooling requirements of the tunnel boring machine and provide sufficient cold source for the working face is a technical problem that the industry urgently needs to solve. Summary of the Invention

[0007] This invention proposes a refrigeration unit with shared cooling water and its control method to solve the technical problems of high cost of using two cooling systems in the prior art, and the inability of sharing one set of equipment to balance the simultaneous cooling of the tunnel boring machine and the working face.

[0008] The technical solution adopted in this invention is to propose a control method for a refrigeration unit with shared cooling water. The refrigeration unit includes a cooling tower, wherein a heat exchanger for cooling a tunnel boring machine is provided between the cooling tower and the refrigeration unit. A bypass is connected to both ends of the heat exchanger, and a bypass valve is provided on the bypass. The control method prioritizes ensuring the normal operation of the tunnel boring machine by adjusting the opening degree of the bypass valve, while adjusting the compressor frequency according to changes in ambient temperature. Finally, the opening degree of the bypass valve is further adjusted according to the change in the power of the refrigeration unit before and after adjusting the opening degree of the bypass valve, so that the entire refrigeration unit is adjusted to operate in an optimal energy consumption state.

[0009] The control methods include: internal temperature control mode of the tunnel boring machine, frequency regulation control mode of the compressor, and energy consumption optimization mode of bypass valve control.

[0010] The internal temperature control mode of the tunnel boring machine is as follows: based on the comparison between the internal temperature of the tunnel boring machine and the set temperature, the opening of the bypass valve is automatically adjusted. When the absolute value of the difference between the set temperature of the tunnel boring machine and the internal temperature of the tunnel boring machine is less than the maximum temperature difference control value and greater than the minimum temperature difference control value, or when the absolute value of the difference between the set temperature of the tunnel boring machine and the internal temperature of the tunnel boring machine is less than or equal to the minimum temperature difference control value, the refrigeration unit enters the bypass valve control energy consumption optimal mode operation.

[0011] In one embodiment, the internal temperature control mode of the tunnel boring machine includes the following steps: Step 11. When the refrigeration unit is started, the bypass valve operates at the initial opening degree d%. Step 12. After the refrigeration unit has been running for a period of time t1, the internal temperature T of the tunnel boring machine is measured. 内 And compare and analyze the internal temperature T 内 and set temperature T 设 Size; Step 13. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is less than or equal to the minimum temperature difference control value, |T 设 -T 内 If |≤h, the current bypass valve opening is taken as the maximum opening m%, and the bypass valve control energy consumption optimal control mode is entered. Step 14. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is less than the maximum temperature difference control value and greater than the minimum temperature difference control value, K > |T 设 -T 内| |>h, the refrigeration unit enters the bypass valve control energy-optimal control mode; Step 15. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is greater than the maximum temperature difference control value, and the internal temperature of the tunnel boring machine is greater than the set temperature, |T 设 -T 内 |>K, and T 内 >T设 Reduce the opening of the bypass valve by a%, then return to step 12 and restart the timing; when the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is greater than the maximum temperature difference control value, and the internal temperature of the tunnel boring machine is less than the set temperature, |T 设 -T 内 |>K, and T 内 <T 设 Increase the opening of the bypass valve by a%, then return to step 12 and restart the timing.

[0012] The compressor frequency control mode automatically adjusts the compressor's operating frequency based on the difference between the ambient temperature and the set ambient temperature.

[0013] like Figure 3 As shown, in one embodiment, the compressor frequency regulation control mode includes the following steps: Step 21. After the unit has been running for a second period of time t2, check the ambient temperature T. 环境 ; Step 22. Calculate the temperature difference between the ambient temperature and the set ambient temperature. Step 23. When the absolute value of the temperature difference between the calculated ambient temperature and the ambient temperature setpoint is less than or equal to the ambient temperature difference control value, |ΔT|≤A, maintain the compressor frequency unchanged, return to step 21, and restart the timing; when the absolute value of the temperature difference between the calculated ambient temperature and the ambient temperature setpoint is greater than the ambient temperature difference control value, |ΔT|>A, then proceed according to either step 24 or step 25 respectively: Step 24. When the temperature difference between the calculated ambient temperature and the set ambient temperature is greater than the ambient temperature difference control value, ΔT > A, control the compressor to increase the frequency by BHz, and then return to step 21 to restart the timing. Step 25. When the temperature difference between the calculated ambient temperature and the set ambient temperature is less than the negative value of the ambient temperature difference control value, ΔT < -A, control the compressor to reduce the frequency by BHz, and then return to step 21 to restart the timing.

[0014] The optimal energy consumption control mode of the bypass valve is to adjust the bypass valve opening by comparing the power of the refrigeration unit before and after the expansion valve opening is adjusted, and to find the optimal bypass valve opening when the power is at its optimal level.

[0015] In one embodiment, the bypass valve control energy-optimized mode includes the following steps: Step 31. When entering the optimal energy consumption mode, detect the system power W1 at this time, and set the first count value X; Step 32. Set the second count value Y, Y = X + 1, and reduce the opening of the bypass valve by b%; Step 33. Determine whether the product of the second count value Y and the second time t2 is less than or equal to the first time t1, Y*t2≤t1. If not, enter the tunnel boring machine internal temperature control mode; if yes, proceed to step 34. Step 34. After the refrigeration unit has been running for a second time t2, detect the system power W2 at this time and compare it with the power W1 before the bypass valve opening was adjusted: Step 35. When the system power after the second time t2 of the chiller unit operation is less than or equal to the power when entering the optimal energy consumption mode, i.e. W2≤W1, increment the first count value X by 1, set W1=W2, and then return to step 32. Step 36. When the system power after the second time t2 is greater than the power when entering the optimal energy consumption mode, i.e. W2 > W1, calculate the opening degree of the bypass valve after adjusting by b%, and then go to step 37. Step 37. Determine whether the opening of the bypass valve after being increased by b% is greater than the maximum opening m%. If yes, make the bypass valve run at the maximum opening m%, then increment the first count value X by 1, set W1=W2, and return to step 32; if no, increase the opening of the bypass valve by b%, then increment the first count value X by 1, set W1=W2, and return to step 32.

[0016] Preferably, the first count value X is initially set to 0, and the first time t1 is an integer multiple of the second time t2.

[0017] The present invention also proposes a refrigeration unit with shared cooling water, including a cooling tower, and a heat exchanger for cooling the inside of a tunnel boring machine is provided between the cooling tower and the refrigeration unit. A bypass is connected to both ends of the heat exchanger, and a bypass valve is provided on the bypass. The refrigeration unit is operated using the control method described above.

[0018] Compared with the prior art, the technical solution proposed in this invention has the following advantages: 1. Based on the air conditioning refrigeration system, the heat exchanger inside the tunnel boring machine is integrated into the cooling water system of the refrigeration unit, which has a high degree of integration and ensures that the cooling of the tunnel boring machine and the air conditioning unit operate synchronously, stably and reliably. 2. By adjusting the opening of the bypass valve, the power of the refrigeration unit before and after frequency adjustment is detected and compared. Based on the comparison results, the opening of the bypass valve is further adjusted so that the refrigeration unit operates in the optimal energy consumption control mode with high energy efficiency ratio. 3. Compared to the scheme of setting up two separate cooling systems for the tunnel boring machine and the air cooling unit, the shared cooling water system reduces investment costs, improves worker comfort, and has advantages such as flexible control, optimal system energy efficiency, and energy saving. Attached Figure Description

[0019] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments, wherein: Figure 1 This is a system diagram of the refrigeration unit with shared cooling water proposed in this invention; Figure 2 This is a flowchart of the internal temperature control mode of a tunnel boring machine; Figure 3 This is a flowchart of the automatic frequency regulation control mode of the refrigeration unit compressor; Figure 4 This is a flowchart of the optimal energy consumption control mode.

[0020] in: 1-Cooling tower; 2-Cooling water pump; 3-Stop valve; 4-Bypass valve; 5-Bypass; 6- Heat exchangers used to cool the interior of the tunnel boring machine; 7- Chilled water pump; 8-Cooling air device; 9-Refrigeration unit; t1 - First time; t2 - Second time; T 内 -The internal temperature of the tunnel boring machine; T 设 - The set temperature of the tunnel boring machine; a-Adjustment range of the bypass valve in the tunnel boring machine temperature detection mode; b - Adjustment range of the bypass valve in energy consumption control mode; d - Initial opening degree of the bypass valve when the refrigeration unit is started; K - Maximum temperature difference control value; h - Minimum temperature difference control value; m - Maximum control opening; T 环境 -Ambient temperature; T 环设 -Ambient temperature setting; ΔT - The difference between ambient temperature and the ambient set temperature; A - Ambient temperature difference control value; B - Compressor frequency adjustment amplitude; W1 - Power of the system before adjusting the opening degree of the bypass valve; W2 - Power of the system after adjusting the opening of the bypass valve; X - First count value; Y - Second count value. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the following specific embodiments are only used to explain the invention and do not constitute a limitation thereof.

[0022] The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of components and steps set forth in these embodiments do not limit the scope of protection of the invention.

[0023] While techniques, methods, and apparatus known to those skilled in the art are not discussed in detail herein, such techniques, methods, and apparatus should be considered part of this specification where appropriate. Any specific values ​​in this specification should be interpreted as merely exemplary and not as limiting the invention.

[0024] For ease of description, the terms used in the specification to describe position, such as "above", "to the left", "in front", etc., are only used to describe the spatial positional relationship between a component and other components in the embodiment shown in the figure. When the position of the component is different, the relative position will change. Therefore, the positional relationship of the embodiment in the figure should not be construed as limiting the present invention.

[0025] Furthermore, it should be noted that the use of terms such as "first" and "second" in the specification is merely for distinguishing similar components and does not imply any order of precedence. Therefore, it should not be construed as limiting the scope of protection of this invention.

[0026] The concept of this invention is to integrate the internal cooling device of the tunnel boring machine (TBM) into the cooling water system of the refrigeration unit, and to install a bypass and a bypass valve in parallel next to the internal cooling device of the TBM. This prioritizes cooling the TBM to ensure its normal operation. Based on this, by detecting changes in ambient temperature, the compressor of the refrigeration unit is automatically frequency-adjusted to adapt its terminal output to changes in ambient temperature. Finally, by comparing the changes in the power of the refrigeration unit before and after the bypass valve opening is adjusted, the opening of the bypass valve is further adjusted to adjust the opening of the bypass valve, so that the entire system operates in the optimal energy consumption mode controlled by the bypass valve.

[0027] Figure 1 This is a system diagram of the refrigeration unit proposed in this invention, which shares a cooling system with the tunnel boring machine. (See diagram for reference.) Figure 1As shown, the refrigeration unit proposed in this invention includes a refrigeration unit 9 connected by pipes, a cold air device 8 for air conditioning terminals, and a chilled water pump 7. The refrigeration unit consists of a compressor, a condenser, an expansion valve, and an evaporator (not shown in the figure). The condenser dissipates heat through a cooling water circulation system consisting of a cooling tower 1 and a cooling water pump 2. The evaporator provides cold air to the tunnel boring machine's working face through a chilled water circulation system consisting of the chilled water pump 7 and the cold air device 8.

[0028] This invention integrates the heat exchanger 6, used for cooling the interior of the tunnel boring machine, into the cooling water circulation system of the refrigeration unit 9. A bypass 5 is connected in parallel at both ends of the heat exchanger 6, and a bypass valve 4 is installed on the bypass. Shut-off valves 3 are installed on both sides of the heat exchanger 6 for easy replacement. During operation, the cooling water, after exchanging heat with the refrigerant in the condenser of the refrigeration unit, is split after passing through the cooling tower 1 and the cooling water pump 2. The flow rate is adjusted by the bypass valve 4, with one portion flowing through the heat exchanger 6 and the other through the bypass 5, and then the two portions are combined and returned to the refrigeration unit 9 for circulation.

[0029] The refrigeration unit proposed in this invention allows the tunnel boring machine and the refrigeration unit to share cooling water. By adjusting the opening of the bypass valve, the cooling water volume of the heat exchanger 6 and the refrigeration unit 9 is regulated. On the basis of meeting the cooling requirements of the tunnel boring machine and the ambient temperature requirements of the working face, the entire system is adjusted to operate in the optimal energy consumption mode controlled by the bypass valve.

[0030] I. System Principles In this invention, the cooling water circulation route is as follows: the cooling water exchanges heat with the high-temperature and high-pressure refrigerant in the condenser of the refrigeration unit. After the heat exchange, the cooling water with the increased temperature enters the cooling tower 1 to cool down. The cooling water flowing out of the cooling tower is divided after passing through the cooling water pump 2. The bypass valve 4 can adjust the flow rate. Part of the cooling water goes to the heat exchanger 6 to cool the tunnel boring machine, and the other part goes through the bypass 5. Then they are combined and returned to the condenser of the refrigeration unit 9 for circulation.

[0031] When the opening degree of bypass valve 4 is reduced, the water flow allocated to heat exchanger 6 increases, the cooling water return temperature rises, and the condensing temperature of refrigeration unit 9 increases, resulting in a decrease in the cooling effect of the refrigeration unit. To maintain a constant cooling capacity, the compressor frequency must increase, leading to an increase in the energy consumption of the refrigeration unit. On the other hand, the tunnel boring machine has a good cooling effect, and the amount of heat dissipated into the working face space is reduced, resulting in a decrease in the cooling load at the end of the refrigeration unit. The required cooling capacity of the refrigeration unit is reduced, so the compressor frequency decreases, leading to a decrease in the energy consumption of the refrigeration unit. Therefore, when the bypass valve is small, the changes in unit energy consumption are quite complex and cannot be easily determined. Conversely, when the bypass valve opening is increased, the water flow allocated to the heat exchanger decreases, the cooling water return temperature drops, the condensing temperature of the refrigeration unit decreases, and the refrigeration unit's cooling effect improves. When the cooling capacity remains constant, the compressor frequency decreases, leading to a reduction in unit energy consumption. Simultaneously, the heat dissipated from the tunnel boring machine into the working face increases, increasing the cooling load at the refrigeration unit's terminals, increasing the unit's cooling capacity, and raising the compressor frequency, resulting in increased refrigeration unit energy consumption. The changes in refrigeration unit energy consumption are complex and cannot be definitively determined. Therefore, during the change in bypass valve opening, it is necessary to find the optimal energy consumption point to optimize the overall system energy consumption, thereby achieving a rational distribution of cooling water.

[0032] II. Control Methods The technical solution proposed in this invention integrates the heat exchanger used to cool the inside of the tunnel boring machine into the cooling water system of the refrigeration unit. The cooling water flow is controlled by a bypass valve. The normal operation of the tunnel boring machine is prioritized by adjusting the opening of the bypass valve. At the same time, the compressor frequency is adjusted according to changes in ambient temperature. Then, the opening of the bypass valve is further adjusted according to the power of the refrigeration unit before and after the bypass valve adjustment, so that the entire refrigeration system is adjusted to operate in the optimal state of energy consumption controlled by the bypass valve.

[0033] The control method proposed in this invention includes the following three aspects: internal temperature control mode of tunnel boring machine, frequency regulation control mode of compressor, and energy consumption optimization mode of bypass valve control.

[0034] 1. Internal temperature control mode of tunnel boring machine.

[0035] The internal temperature control mode of the tunnel boring machine is to automatically adjust the opening of the bypass valve based on the comparison between the internal temperature of the tunnel boring machine and the set temperature of the tunnel boring machine, so that the tunnel boring machine can work normally. When the absolute value of the difference between the set temperature of the tunnel boring machine and the internal temperature of the tunnel boring machine is less than the maximum temperature difference control value and greater than the minimum temperature difference control value, the refrigeration unit enters the energy-optimized control mode.

[0036] The internal temperature control mode of the tunnel boring machine includes the following steps: Step 11. When the refrigeration unit is started, the bypass valve operates at the initial opening degree d%. Step 12. After the refrigeration unit has been running for a period of time t1, the internal temperature T of the tunnel boring machine is measured. 内 And compare and analyze the internal temperature T of the shield's structure. 内 and set temperature T 设 Size; Step 13. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is less than or equal to the minimum temperature difference control value, |T 设 -T 内 If |≤h, the current bypass valve opening is taken as the maximum opening m%, and the bypass valve control energy consumption optimal control mode is entered. Step 14. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is less than the maximum temperature difference control value and greater than the minimum temperature difference control value, K > |T 设 -T 内| >h, the refrigeration unit enters the bypass valve control energy-optimized control mode; Step 15. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is greater than the maximum temperature difference control value, and the internal temperature of the tunnel boring machine is greater than the set temperature, |T 设 -T 内 |>K, and T 内 >T 设 Reduce the opening of the bypass valve by a%, then return to step 12 and restart the timing; when the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is greater than the maximum temperature difference control value, and the internal temperature of the tunnel boring machine is less than the set temperature, |T 设 -T 内 |>K, and T 内 <T 设 Increase the opening of the bypass valve by a%, then return to step 12 and restart the timing.

[0037] 2. Automatic frequency adjustment control mode for compressor.

[0038] The compressor frequency control mode automatically adjusts the compressor's operating frequency based on the difference between the ambient temperature and the set ambient temperature.

[0039] The compressor's automatic frequency control mode includes the following steps: Step 21. After the unit has been running for a second period of time t2, check the ambient temperature T. 环境 ; In this embodiment, t2 is 2 seconds, and the relationship between the second time t2 and the first time t1 is: t1 = nt2, where n is a constant, that is, the first time t1 is a multiple of the second time t2. In this embodiment, n = 2. Step 22. Calculate the temperature difference between the ambient temperature and the set ambient temperature. ΔT=T 环境 -T环设 And analyze the temperature difference: Step 23. When the absolute value of the temperature difference between the calculated ambient temperature and the ambient temperature setpoint is less than or equal to the ambient temperature difference control value, |ΔT|≤A, indicating that the ambient temperature T 环境 Within the temperature fluctuation range, maintain the compressor frequency unchanged, return to step 21, and restart the timing; When the absolute value of the temperature difference between the calculated ambient temperature and the set ambient temperature is greater than the ambient temperature difference control value, |ΔT|>A, then proceed according to step 24 or step 25 respectively: Step 24. When the temperature difference between the calculated ambient temperature and the set ambient temperature is greater than the ambient temperature difference control value, ΔT>A, indicating that the ambient temperature is too high. At this time, control the compressor to increase the frequency by BHz, and then return to step 21 to start timing again. Step 25. When the calculated ambient temperature difference from the ambient temperature setpoint is less than the negative value of the ambient temperature difference control value, ΔT < -A, indicating that the ambient temperature T 环境 If the frequency is too low, the compressor will be reduced to BHz, and then the process will return to step 21 to restart the timing.

[0040] In this embodiment, B is 5.

[0041] 3. Bypass valve control for optimal energy consumption.

[0042] The optimal energy consumption control mode of the bypass valve is to further adjust the opening of the bypass valve by comparing the power of the refrigeration unit before and after the bypass valve adjustment, in order to find the optimal opening of the bypass valve when the power is optimal.

[0043] The bypass valve control energy-optimized mode includes the following steps: Step 31. Upon entering the optimal energy consumption mode, detect the current system power W1, and set the first count value X, X=0; Step 32. Set the second count value Y, Y = X + 1, and reduce the opening of the bypass valve by b%; In this embodiment, b% is 2%.

[0044] Step 33. Determine whether the product of the second count value and the second time is less than or equal to the first time, Y*t2≤t1; and when the product of the second count value and the second time is greater than the first time, Y*t2>t1, and enter the tunnel boring machine internal temperature control mode; when the product of the second count value and the second time is less than or equal to the first time, Y*t2≤t1, and go to step 34. Step 34. After the refrigeration unit has been running for a second time t2, measure the system power W2 at this time and compare it with the power W1 before adjusting the bypass valve opening: Step 35. When the system power after the second time t2 is less than or equal to the power when entering the optimal energy consumption mode, W2≤W1, increment the first count value X by 1, X=X+1, set W1=W2, and then return to step 32; Step 36. When the system power after the second time t2 is greater than the power when entering the optimal energy consumption mode, W2 > W1. Calculate the opening degree of the bypass valve after adjusting it by b%, and then proceed to step 37. Step 37. Determine whether the opening of the bypass valve after being increased by b% is greater than the maximum opening m%. If yes, make the bypass valve operate at the maximum opening m%, then increment the first count value X by 1, X = X + 1, set W1 = W2, and return to step 32; if no, increase the opening of the bypass valve by b%, then increment the first count value X by 1, X = X + 1, set W1 = W2, and return to step 32.

[0045] In summary, this invention adjusts the compressor's operating frequency by regulating the opening of the bypass valve, compares the power of the refrigeration units before and after the bypass valve adjustment, and further adjusts the bypass valve opening to ensure the refrigeration units operate at their lowest energy consumption. Compared to existing technologies that use two separate cooling systems for the tunnel boring machine and the air cooling unit, or share a cooling water system, this reduces investment costs, improves worker comfort, and offers advantages such as flexible control and energy savings.

[0046] The technical solution proposed in this invention is not limited to the environment in which tunnel boring machines operate; it can also be used in other equipment and workspaces that require cooling.

[0047] The above description is merely a specific embodiment of the present invention. It should be noted that any modifications, equivalent substitutions, and variations made within the spirit and framework of the present invention should be included within the protection scope of the present invention.

Claims

1. A control method for a refrigeration unit sharing cooling water, the refrigeration unit comprising a cooling tower, characterized in that, A heat exchanger for cooling the tunnel boring machine is installed between the cooling tower and the refrigeration unit. A bypass is connected to both ends of the heat exchanger, and a bypass valve is installed on the bypass. The control method prioritizes the normal operation of the tunnel boring machine by adjusting the opening of the bypass valve, while adjusting the compressor frequency according to changes in ambient temperature. Finally, the opening of the bypass valve is further adjusted based on the change in the power of the refrigeration unit before and after adjusting the bypass valve opening, so that the entire refrigeration unit operates in the optimal energy consumption state. Specifically, this includes adjusting the bypass valve opening by comparing the power of the refrigeration unit before and after adjusting the bypass valve opening, and seeking the opening of the bypass valve at the optimal power.

2. The control method as described in claim 1, characterized in that, The control methods include: internal temperature control mode of the tunnel boring machine, frequency regulation control mode of the compressor, and energy consumption optimization mode of bypass valve control.

3. The control method according to claim 2, characterized in that, The internal temperature control mode of the tunnel boring machine is as follows: based on the comparison between the internal temperature of the tunnel boring machine and the set temperature, the opening of the bypass valve is automatically adjusted. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is less than the maximum temperature difference control value and greater than the minimum temperature difference control value, or when the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is less than or equal to the minimum temperature difference control value, the refrigeration unit enters the bypass valve control energy consumption optimal mode for operation.

4. The control method as described in claim 3, characterized in that, The internal temperature control mode of the tunnel boring machine includes the following steps: Step 11. When the refrigeration unit is started, the bypass valve operates at the initial opening degree d%. Step 12. After the refrigeration unit has been running for a period of time t1, the internal temperature T of the tunnel boring machine is measured. 内 And compare and analyze the internal temperature T 内 and set temperature T 设 Size; Step 13. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is less than or equal to the minimum temperature difference control value, |T 设 -T 内 If |≤h, the current bypass valve opening is taken as the maximum opening m%, and the bypass valve control energy consumption optimal control mode is entered. Step 14. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is less than the maximum temperature difference control value and greater than the minimum temperature difference control value, K > |T 设 -T 内| >h, the refrigeration unit enters the bypass valve control energy-optimized control mode; Step 15. When the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is greater than the maximum temperature difference control value, and the internal temperature of the tunnel boring machine is greater than the set temperature, |T 设 -T 内 |>K, and T 内 >T 设 Reduce the opening of the bypass valve by a%, then return to step 12 and restart the timing; when the absolute value of the difference between the set temperature and the internal temperature of the tunnel boring machine is greater than the maximum temperature difference control value, and the internal temperature of the tunnel boring machine is less than the set temperature, |T 设 -T 内 |>K, And T 内 <T 设 Increase the opening of the bypass valve by a%, then return to step 12 and restart the timing.

5. The control method as described in claim 2, characterized in that, The compressor frequency control mode automatically adjusts the compressor's operating frequency based on the difference between the ambient temperature and the set ambient temperature.

6. The control method according to claim 5, characterized in that, The compressor frequency regulation control mode includes the following steps: Step 21. After the unit has been running for a second period of time t2, check the ambient temperature T. 环境 ; Step 22. Calculate the temperature difference between the ambient temperature and the set ambient temperature. Step 23. When the absolute value of the temperature difference between the calculated ambient temperature and the ambient temperature setpoint is less than or equal to the ambient temperature difference control value, |ΔT|≤A, maintain the compressor frequency unchanged, return to step 21, and restart the timing; when the absolute value of the temperature difference between the calculated ambient temperature and the ambient temperature setpoint is greater than the ambient temperature difference control value, |ΔT|>A, then proceed according to either step 24 or step 25 respectively: Step 24. When the temperature difference between the calculated ambient temperature and the set ambient temperature is greater than the ambient temperature difference control value, ΔT > A, control the compressor to increase the frequency by BHz, and then return to step 21 to restart the timing. Step 25. When the temperature difference between the calculated ambient temperature and the set ambient temperature is less than the negative value of the ambient temperature difference control value, ΔT < -A, control the compressor to reduce the frequency by BHz, and then return to step 21 to restart the timing.

7. The control method as described in claim 2, characterized in that, The bypass valve control energy-optimized mode includes the following steps: Step 31. When entering the optimal energy consumption mode, detect the system power W1 at this time, and set the first count value X; Step 32. Set the second count value Y, Y = X + 1, and reduce the opening of the bypass valve by b%; Step 33. Determine whether the product of the second count value Y and the second time t2 is less than or equal to the first time t1, Y*t2≤t1. If not, enter the tunnel boring machine internal temperature control mode; if yes, proceed to step 34. Step 34. After the refrigeration unit has been running for a second time t2, detect the system power W2 at this time and compare it with the power W1 before the bypass valve opening was adjusted: Step 35. When the system power after the second time t2 of the chiller unit is less than or equal to the power when entering the optimal energy consumption mode, W2≤W1, increment the first count value X by 1, set W1=W2, and then return to step 32; Step 36. When the system power after the second time t2 is greater than the power when entering the optimal energy consumption mode, W2 > W1. Calculate the opening degree of the bypass valve after adjusting it by b%, and then proceed to step 37. Step 37. Determine whether the opening of the bypass valve after being increased by b% is greater than the maximum opening m%. If yes, make the bypass valve run at the maximum opening m%, then increment the first count value X by 1, set W1=W2, and return to step 32; if no, increase the opening of the bypass valve by b%, then increment the first count value X by 1, set W1=W2, and return to step 32.

8. The control method as described in claim 7, characterized in that, The first count value X is initially set to 0, and the first time t1 is an integer multiple of the second time t2.

9. A refrigeration unit with shared cooling water, comprising a cooling tower, characterized in that, A heat exchanger for cooling the tunnel boring machine is provided between the cooling tower and the refrigeration unit. A bypass is connected to both ends of the heat exchanger, and a bypass valve is provided on the bypass. The refrigeration unit is operated using the control method described in any one of claims 1-8.

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