Control method of dual-system ultralow-temperature preservation box

Abstract

The invention belongs to the technical field of refrigeration, and provides a control method of a dual-system ultralow-temperature storage box, which comprises the following steps: selecting operation modes through a display screen of the ultralow-temperature storage box, the operation modes including a high-performance mode, a low-noise mode and an energy-saving mode; if the high-performance mode or the low-noise mode is selected, a compressor in the dual-system ultralow-temperature storage box operates by adopting a first control logic, and if the energy-saving mode is selected, the compressor in the dual-system ultralow-temperature storage box operates by adopting a second control logic; and in the high-performance mode, the low-noise mode and the energy-saving mode, the variable-frequency condensation fan operates by adopting a third control logic. The control mode of the dual-system ultralow-temperature storage box can be selected according to the requirements of a user, and the multi-scene use requirements of the user are met.

Description

Technical Field

[0001] The invention belongs to the technical field of refrigeration, and in particular, relates to a control method for a dual-system ultra-low temperature storage box. Background Art

[0002] In the medical industry, -80℃ ultra-low temperature storage boxes are widely used and are generally suitable for hospitals, research institutes, universities, disease control centers, electronic chemical industry and other corporate laboratories and other industry institutions for storing viruses, bacteria, cells, biological products, electronic devices, etc.

[0003] As people pay more and more attention to the medical industry, ultra-low temperature preservation boxes are becoming more and more well-known, especially in scenarios such as biological sample storage, low-temperature testing of electronic devices and special materials. The application of multiple scenarios and multiple frequencies has greatly increased the demand for ultra-low temperature preservation boxes, and also put forward higher requirements on the performance of ultra-low temperature preservation boxes. There are many kinds of ultra-low temperature preservation boxes on the market, but with the development of industry and technology, people have put forward higher requirements on the safety of ultra-low temperature preservation boxes, and the number of ultra-low temperature preservation boxes using dual refrigeration systems has gradually increased. However, the control method of the dual-system ultra-low temperature preservation boxes on the current market is simple, and can only achieve a single control state. During use, there may be problems such as high energy consumption, noise interference, poor temperature control uniformity, and slow cooling, which seriously restricts its use effect and application scope. Summary of the invention

[0004] In order to solve the deficiencies in the prior art, the present invention provides a control method for a dual-system ultra-low temperature preservation box, which adopts dual frequency conversion technology of a variable frequency compressor and a variable frequency condensing fan, and can select the control mode of the dual-system ultra-low temperature preservation box according to user needs, thereby achieving the advantages of energy saving, low noise, uniform temperature control, and fast cooling in one ultra-low temperature preservation box, thereby meeting the user's usage needs in multiple scenarios.

[0005] The present invention adopts the following technical solution.

[0006] A control method for a dual-system ultra-low temperature preservation box, the dual-system ultra-low temperature preservation box comprising a main control panel, a display screen, a control sensor and two independent refrigeration systems, each refrigeration system comprising a compressor, a compressor inverter, a variable frequency condensing fan and a condenser sensor; the control method for the dual-system ultra-low temperature preservation box comprises:

[0007] Selecting an operating mode through a display screen of the ultra-low temperature preservation box, wherein the operating mode includes a high performance mode, a low noise mode and an energy saving mode;

[0008] If the high performance mode or the low noise mode is selected, the compressor in the dual system ultra-low temperature storage box adopts the first control logic to operate; if the energy saving mode is selected, the compressor in the dual system ultra-low temperature storage box adopts the second control logic to operate;

[0009] In the first control logic, according to the difference between the temperature in the ultra-low temperature storage box and the set temperature, the dual compressors are operated at the highest speed, the dual compressors are operated at a speed-controlled speed, or the single compressor is operated at a speed-controlled speed;

[0010] In the second control logic, the dual compressors are operated at variable speeds according to the temperature in the ultra-low temperature storage box;

[0011] The variable frequency condensing fan in the high performance mode, low noise mode and energy saving mode adopts the third control logic to operate;

[0012] In the third control logic, according to the condenser temperature and the operating conditions of the compressor in each refrigeration system, the variable frequency condensing fan is operated at the highest speed, the variable frequency condensing fan is operated at a variable speed, or the variable frequency condensing fan is operated at the lowest speed.

[0013] Furthermore, the first control logic includes:

[0014] S11: Determine the difference between the temperature inside the ultra-low temperature storage box and the set temperature Relationship with him / her;

[0015] S111: If , then the dual compressors run at the highest speed n1 and enter S11;

[0016] S112: If , the dual compressors are operated at speeds adjusted by the PID control algorithm and enter S12;

[0017] S12: Determine the difference between the temperature inside the ultra-low temperature storage box and the set temperature and Tb, where Tb<Ta;

[0018] S121: If , the dual compressors continue to operate at speeds regulated by the PID control algorithm and enter S12;

[0019] S122: If , then the single compressor operates at a speed controlled by the PID control algorithm and enters S13;

[0020] S13: Determine the difference between the temperature inside the ultra-low temperature storage box and the set temperature Relationship with Tb;

[0021] S131: If , the compressor stops running, and it is judged whether the temperature in the ultra-low temperature storage box reaches the startup temperature. If the temperature in the ultra-low temperature storage box does not reach the startup temperature, the compressor continues to stop running. If the temperature in the ultra-low temperature storage box reaches the startup temperature, it enters S11;

[0022] S132: If , then the difference between the temperature inside the ultra-low temperature storage box and the set temperature is determined The relationship between and Tc, where Tb<Tc; if , then enter S11, if , the single compressor runs at a speed controlled by the PID control algorithm and enters S13.

[0023] Furthermore, in said S11, S12, and S13, the temperature in the ultra-low temperature storage box is monitored by a control sensor and the temperature data is transmitted to the main control board;

[0024] The Ta is 3°C, the Tb is -1°C, and the Tc is 1°C.

[0025] Further, when the high performance mode is selected, in the first control logic S111, the maximum speed of the compressor is the rated maximum speed, and n1 is 4500 rpm;

[0026] When the low noise mode is selected, in the first control logic S111, the maximum speed of the compressor is the limited maximum speed, and n1 is 3000 rpm.

[0027] Furthermore, the second control logic includes:

[0028] S21: Determine whether the startup temperature has been reached. If not, the machine will not be started. If the startup temperature has been reached, the dual compressors will start running at intervals, and the speed will be adjusted by the PID control algorithm, and then enter S22;

[0029] S22: Determine whether the shutdown temperature is reached. If the shutdown temperature is not reached, the compressor continues to run. If the shutdown temperature is reached, the compressor stops and enters S21.

[0030] Furthermore, the startup temperature is the set temperature + 1°C, and the shutdown temperature is the set temperature - 1°C.

[0031] Furthermore, the third control logic includes:

[0032] S31: Determine the relationship between the condensation temperature Tn and Tmax;

[0033] S311: If Tn>Tmax, the variable frequency condensing fan runs at the maximum speed n2 and enters S31;

[0034] S312: If Tn≤Tmax, the variable frequency condensing fan operates at a speed controlled by the PID control algorithm within the speed range and enters S32;

[0035] S32: Determine whether the compressor in the refrigeration system where the variable frequency condensing fan is located is stopped;

[0036] S321: If the compressor stops, the variable frequency condensing fan runs at the lowest speed n3 and enters S32;

[0037] S322: If the compressor is not stopped, enter S31.

[0038] Furthermore, in said S31, the condenser sensor monitors the condenser temperature and transmits the condensation temperature information Tn to the main control board;

[0039] The Tmax is 45°C. In the high performance mode and energy saving mode, the maximum speed n2 of the variable frequency condensing fan is the rated maximum speed, which is 1500 rpm. In the low noise mode, the maximum speed of the variable frequency condensing fan is the limited maximum speed, which is 1000 rpm.

[0040] The minimum speed n3 of the variable frequency condensing fan is 500rpm.

[0041] Furthermore, the PID control algorithm speed regulation operation is:

[0042] The main control board calculates the appropriate compressor speed through the PID control algorithm based on the difference between the set temperature and the temperature inside the ultra-low temperature preservation box, and controls the compressor speed through the compressor inverter; the main control board maintains the variable frequency condensing fan within the speed range through the PID control algorithm based on the difference between the condensing temperature of the condenser and Tmax.

[0043] The beneficial effect of the present invention is that, compared with the prior art, the control method of the dual-system ultra-low temperature preservation box provided by the present invention can select the operating mode of the ultra-low temperature preservation box according to the needs of the user, so as to meet the use needs of the user in different scenarios. When the high-performance mode is selected, the ultra-low temperature preservation box can provide more stringent temperature uniformity, which is particularly important for scientific research and medical applications that require high-precision temperature control. In addition, this mode has a faster refrigeration speed, which can quickly reduce the temperature inside the preservation box to the required level, saving time. When the low-noise mode is selected, by controlling the speed of the compressor and the variable-frequency condensing fan, the noise generated during operation is reduced, and the user's comfort during use is improved. At the same time, long-term noise pollution may cause damage to the mechanical parts of the equipment, and the low-noise mode helps to extend the service life of the equipment. When the energy-saving mode is selected, the operating cost of the ultra-low temperature preservation box can be reduced, energy consumption can be reduced, and stable temperature control can be maintained to ensure the safe storage of biological samples. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a control principle diagram of the dual-system ultra-low temperature storage box of the present invention;

[0045] Figure 2 It is the first control logic flow chart of the present invention;

[0046] Figure 3 It is the second control logic flow chart of the present invention;

[0047] Figure 4 It is the third control logic flow chart in the present invention. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in this application are only embodiments of a part of the present invention, rather than all embodiments. Based on the spirit of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present invention.

[0049] like Figure 1 As shown, the present invention provides a control method for a dual-system ultra-low temperature preservation box, wherein the dual-system ultra-low temperature preservation box includes a main control panel, a display screen, a control sensor, and two independent refrigeration systems, wherein the first refrigeration system includes a first compressor, a first compressor inverter, a first variable frequency condensing fan, and a first condenser sensor, and the second refrigeration system includes a second compressor, a second compressor inverter, a second variable frequency condensing fan, and a second condenser sensor;

[0050] The display screen is connected to the main control board. The user selects the operation mode of the dual-system ultra-low temperature preservation box through the display screen. The display screen transmits the instruction to the main control board. The display screen receives and displays the temperature data in the ultra-low temperature preservation box and the temperature data of the condenser transmitted by the main control board.

[0051] The control sensor is connected to the main control board, and the control sensor transmits the temperature information in the ultra-low temperature insulation box to the main control board;

[0052] The condenser sensor is connected to the main control board, the first condenser sensor transmits the condenser temperature in the first refrigeration system to the main control board, and the second condenser sensor transmits the condenser temperature in the second refrigeration system to the main control board;

[0053] The main control board is connected to the first compressor through the first compressor inverter, and is connected to the second compressor through the second compressor inverter. The main control board is connected to the first variable frequency condensing fan and the second variable frequency condensing fan; the main control board receives the temperature signal transmitted by the control sensor and the condenser sensor, and transmits the new speed signal to the first compressor inverter, the second compressor inverter, the first variable frequency condensing fan and the second variable frequency condensing fan after control logic processing.

[0054] The control method of the dual-system ultra-low temperature storage box includes:

[0055] Selecting an operating mode through a display screen of the ultra-low temperature preservation box, wherein the operating mode includes a high performance mode, a low noise mode and an energy saving mode;

[0056] If the high-performance mode or the low-noise mode is selected, the compressor in the dual-system ultra-low temperature preservation box adopts the first control logic to operate; if the energy-saving mode is selected, the compressor in the dual-system ultra-low temperature preservation box adopts the second control logic to operate; the variable frequency condensing fan adopts the third control logic to operate in the high-performance mode, low-noise mode and energy-saving mode.

[0057] like Figure 2 As shown, in the first control logic, according to the difference between the temperature in the ultra-low temperature storage box and the set temperature, the dual compressors are operated at the highest speed, the dual compressors are operated at a speed-adjustable speed, or the single compressor is operated at a speed-adjustable speed;

[0058] Specifically, the first control logic includes:

[0059] S11: Determine the difference between the temperature inside the ultra-low temperature storage box and the set temperature The relationship between Ta and Ta is 3℃;

[0060] S111: If , then the dual compressors run at the maximum speed n1. When the high performance mode is selected, the rated maximum speed n1 of the compressor is 4500rpm. When the low noise mode is selected, the maximum speed of the compressor is the limited maximum speed, n1 is 3000rpm.

[0061] S112: If , the dual compressors are operated at speeds adjusted by the PID control algorithm and enter S12;

[0062] S12: Determine the difference between the temperature inside the ultra-low temperature storage box and the set temperature The relationship between Tb and Ta, where Tb < Ta, Tb is -1 °C;

[0063] S121: If , the dual compressors continue to rotate by adjusting the compressor speed through PID control and enter S12;

[0064] S122: If , then the single compressor operates at a speed controlled by the PID control algorithm and enters S13;

[0065] S13: Determine the difference between the temperature inside the ultra-low temperature storage box and the set temperature Relationship with Tb;

[0066] S131: If , the compressor stops running, and it is judged whether the temperature in the ultra-low temperature storage box reaches the startup temperature. If the temperature in the ultra-low temperature storage box does not reach the startup temperature, the compressor continues to stop running. If the temperature in the ultra-low temperature storage box reaches the startup temperature, it enters S11;

[0067] The startup temperature is the set temperature + 1°C;

[0068] S132: If , then the difference between the temperature inside the ultra-low temperature storage box and the set temperature is determined The relationship between Tb and Tc, where Tb < Tc, Tc is 1°C; if , then enter S11, if , the single compressor runs at a speed controlled by the PID control algorithm and enters S13.

[0069] like Figure 3 As shown, in the second control logic, the dual compressors are operated at variable speeds according to the temperature in the ultra-low temperature storage box;

[0070] Specifically, the second control logic includes:

[0071] S21: Determine whether the startup temperature has been reached. If not, the machine will not be started. If the startup temperature has been reached, the dual compressors will start running at intervals, and the speed will be adjusted by the PID control algorithm, and then enter S22;

[0072] The startup temperature is the set temperature + 1°C;

[0073] S22: Determine whether the shutdown temperature is reached. If the shutdown temperature is not reached, the compressor continues to run. If the shutdown temperature is reached, the compressor stops and enters S21;

[0074] The shutdown temperature is the set temperature -1°C.

[0075] like Figure 4 As shown, in the third control logic, according to the condenser temperature and the operating conditions of the compressor in each refrigeration system, the variable frequency condensing fan is operated at the maximum speed, the variable frequency condensing fan is operated at a speed adjustment, or the variable frequency condensing fan is operated at the minimum speed.

[0076] Specifically, the third control logic includes:

[0077] S31: The condenser sensor monitors the condenser temperature and transmits the condensation temperature information to the main control board, and the main control board determines the relationship between the condensation temperature Tn and Tmax, and the value of Tmax is 45°C;

[0078] S311: If Tn>Tmax, the variable frequency condensing fan runs at the maximum speed n2 and enters S31;

[0079] In high performance mode and energy saving mode, the maximum speed n2 of the variable frequency condensing fan is the rated maximum speed, which is 1500 rpm. In low noise mode, the maximum speed of the variable frequency condensing fan is the limited maximum speed, which is 1000 rpm.

[0080] S312: If Tn≤Tmax, the variable frequency condensing fan is operated at a speed controlled by a PID control algorithm within a speed range and enters S32, wherein the speed range is 500-1500 rpm;

[0081] S32: Determine whether the compressor in the refrigeration system where the variable frequency condensing fan is located is stopped;

[0082] S321: If the compressor stops, the variable frequency condensing fan runs at the lowest speed n3 and enters S32;

[0083] Among them, the minimum speed n3 of the variable frequency condensing fan is 500rpm;

[0084] S322: If the compressor is not stopped, enter S31.

[0085] The dual compressor speed regulation operation, single compressor speed regulation operation and variable frequency condensing fan speed regulation operation are that the main control board adjusts the speed of the compressor or variable frequency condensing fan in real time through the PID control logic; the main control board calculates the appropriate compressor speed through the PID control algorithm according to the difference between the set temperature and the temperature in the ultra-low temperature preservation box, and controls the compressor speed through the compressor inverter; the main control board maintains the variable frequency condensing fan within the speed range through the PID control algorithm according to the difference between the condensing temperature of the condenser and Tmax.

[0086] 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 above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A control method for a dual-system ultra-low temperature storage box, characterized in that: The dual-system ultra-low temperature preservation box includes a main control panel, a display screen, a control sensor and two independent refrigeration systems, each refrigeration system includes a compressor, a compressor inverter, a variable frequency condensing fan and a condenser sensor; the control method of the dual-system ultra-low temperature preservation box includes: Selecting an operating mode through a display screen of the ultra-low temperature preservation box, wherein the operating mode includes a high performance mode, a low noise mode and an energy saving mode; If the high performance mode or the low noise mode is selected, the compressor in the dual system ultra-low temperature storage box adopts the first control logic to operate; if the energy saving mode is selected, the compressor in the dual system ultra-low temperature storage box adopts the second control logic to operate; In the first control logic, according to the difference between the temperature in the ultra-low temperature storage box and the set temperature, the dual compressors are operated at the highest speed, the dual compressors are operated at a speed-controlled speed, or the single compressor is operated at a speed-controlled speed; In the second control logic, the dual compressors are operated at variable speeds according to the temperature in the ultra-low temperature storage box; The variable frequency condensing fan in the high performance mode, low noise mode and energy saving mode adopts the third control logic to operate; In the third control logic, according to the condenser temperature and the operating conditions of the compressor in each refrigeration system, the variable frequency condensing fan is operated at the maximum speed, the variable frequency condensing fan is operated at a speed adjustment, or the variable frequency condensing fan is operated at the minimum speed.

2. The control method of a dual-system ultra-low temperature storage box according to claim 1, characterized in that: The first control logic includes: S11: Determine the difference between the temperature inside the ultra-low temperature storage box and the set temperature Relationship with him / her; S111: If , then the dual compressors run at the highest speed n1 and enter S11; S112: If , the dual compressors are operated at speeds adjusted by the PID control algorithm and enter S12; S12: Determine the difference between the temperature inside the ultra-low temperature storage box and the set temperature and Tb, where Tb<Ta; S121: If , the dual compressors continue to operate at speeds regulated by the PID control algorithm and enter S12; S122: If , then the single compressor operates at a speed controlled by the PID control algorithm and enters S13; S13: Determine the difference between the temperature inside the ultra-low temperature storage box and the set temperature Relationship with Tb; S131: If , the compressor stops running, and it is judged whether the temperature in the ultra-low temperature storage box reaches the startup temperature. If the temperature in the ultra-low temperature storage box does not reach the startup temperature, the compressor continues to stop running. If the temperature in the ultra-low temperature storage box reaches the startup temperature, it enters S11; S132: If , then the difference between the temperature inside the ultra-low temperature storage box and the set temperature is determined The relationship between and Tc, where Tb<Tc; if , then enter S11, if , the single compressor runs at a speed controlled by the PID control algorithm and enters S13.

3. The control method of a dual-system ultra-low temperature storage box according to claim 2, characterized in that: In the above S11, S12 and S13, the temperature in the ultra-low temperature storage box is monitored by the control sensor and the temperature data is transmitted to the main control board; The Ta is 3°C, the Tb is -1°C, and the Tc is 1°C.

4. The control method of a dual-system ultra-low temperature storage box according to claim 3, characterized in that: When the high performance mode is selected, in the first control logic S111, the maximum speed of the compressor is the rated maximum speed, and n1 is 4500 rpm; When the low noise mode is selected, in the first control logic S111, the maximum speed of the compressor is the limited maximum speed, and n1 is 3000 rpm.

5. The control method of a dual-system ultra-low temperature storage box according to claim 3, characterized in that: The second control logic includes: S21: Determine whether the startup temperature has been reached. If not, the machine will not be started. If the startup temperature has been reached, the dual compressors will start running at intervals, and the speed will be adjusted by the PID control algorithm, and then enter S22; S22: Determine whether the shutdown temperature is reached. If the shutdown temperature is not reached, the compressor continues to run. If the shutdown temperature is reached, the compressor stops and enters S21.

6. The control method of a dual-system ultra-low temperature storage box according to claim 5, characterized in that: The startup temperature is the set temperature + 1°C, and the shutdown temperature is the set temperature - 1°C.

7. The control method of a dual-system ultra-low temperature storage box according to claim 6, characterized in that: The third control logic includes: S31: Determine the relationship between the condensation temperature Tn and Tmax; S311: If Tn>Tmax, the variable frequency condensing fan runs at the maximum speed n2 and enters S31; S312: If Tn≤Tmax, the variable frequency condensing fan is operated at a speed controlled by the PID control algorithm within the speed range and enters S32; S32: Determine whether the compressor in the refrigeration system where the variable frequency condensing fan is located is stopped; S321: If the compressor stops, the variable frequency condensing fan runs at the lowest speed n3 and enters S32; S322: If the compressor is not stopped, enter S31.

8. The control method of a dual-system ultra-low temperature storage box according to claim 7, characterized in that: In S31, the condenser sensor monitors the condenser temperature and transmits the condensation temperature information Tn to the main control board; The Tmax is 45°C. In the high performance mode and energy saving mode, the maximum speed n2 of the variable frequency condensing fan is the rated maximum speed, which is 1500 rpm. In the low noise mode, the maximum speed n2 of the variable frequency condensing fan is the limited maximum speed, which is 1000 rpm. The minimum speed n3 of the variable frequency condensing fan is 500rpm.

9. The control method of a dual-system ultra-low temperature storage box according to claim 8, characterized in that: The PID control algorithm speed regulation operation is: The main control board calculates the appropriate compressor speed through the PID control algorithm based on the difference between the set temperature and the temperature inside the ultra-low temperature preservation box, and controls the compressor speed through the compressor inverter; the main control board maintains the variable frequency condensing fan within the speed range through the PID control algorithm based on the difference between the condensing temperature of the condenser and Tmax.

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