High load control method and system for container data center cooling equipment

Abstract

The present invention relates to a high-load control method and system for cooling equipment of a container data center, the method comprising: judging whether the ambient temperature T0 reaches a first preset threshold; if so, collecting the temperature T1 of the outlet of the cooling liquid of the liquid cooling cabinet, judging whether the temperature (T1-A) / T0 is greater than the first target threshold; if so, judging whether the temperature integral median of T1-T0 in the target time period is greater than the second target threshold; if so, judging whether the first-order derivative change of the temperature T1 in adjacent collection cycles is greater than the third target threshold; if so, recollecting the temperature T1 and judging whether the temperature T1 is greater than the target temperature threshold; if so, the liquid pump operates at the maximum frequency or at the sum of the rated frequency and the predetermined frequency addition amount, the water pump operates at the maximum frequency or at the sum of the rated frequency and the predetermined frequency addition amount, and the cooling tower fan and the cooling tower water pump operate at the limit frequency. The present invention realizes the safe operation of the container data center.

Description

Technical Field

[0001] The present invention belongs to the technical field of overload control of cooling equipment of a container data center, and in particular relates to a high load control method and system for cooling equipment of a container data center. Background Art

[0002] The container data center is configured in a container and equipped with many rack-mounted servers for data processing. It has the advantages of small footprint, ability to accommodate high-density computing equipment, and low power usage efficiency (PUE).

[0003] Existing container data centers generally use liquid cooling, for example, the liquid cooling system of a container data center disclosed in patent document No. CN103901985A. For a liquid cooling system, once the liquid cooling system stops cooling for about 30 seconds, the server will not be able to work normally due to high temperature; therefore, the liquid cooling system needs to have high reliability.

[0004] The control method of the existing liquid cooling system is relatively simple, and is controlled by too many parameters in a disorderly manner, making the control more complicated. Summary of the invention

[0005] Based on the above-mentioned shortcomings and deficiencies in the prior art, one of the objects of the present invention is to at least solve one or more of the above-mentioned problems in the prior art. In other words, one of the objects of the present invention is to provide a high-load control method and system for container data center cooling equipment that meets one or more of the above-mentioned requirements.

[0006] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0007] A high-load control method for a container data center cooling device, wherein the container data center cooling device comprises a liquid cooling cabinet, a heat exchanger and a cooling tower, wherein the liquid side inlet and the liquid side outlet of the heat exchanger are respectively connected to the coolant inlet and the outlet of the liquid cooling cabinet to form a circulating flow path of the coolant, and the circulating flow path of the coolant is provided with a liquid pump; the water side inlet and the water side outlet of the heat exchanger are respectively connected to the water outlet and the water inlet of the cooling tower to form a circulating flow path of the cooling water, and the circulating flow path of the cooling water is provided with a water pump, and the high-load control method comprises the following steps:

[0008] S1, collecting the ambient temperature and determining whether the ambient temperature T0 reaches a first preset threshold; if so, the liquid pump, the water pump and the cooling tower operate according to the first preset target conditions, and go to step S2;

[0009] S2, collecting the temperature T1 of the outlet of the cooling liquid of the liquid cooling cabinet, and determining whether the temperature (T1-A) / T0 is greater than the first target threshold; if so, proceeding to step S3; if not, returning to step S1; wherein A is the temperature threshold;

[0010] S3, determining whether the temperature integral median of T1-T0 within the target time period is greater than the second target threshold; if so, proceeding to step S4; if not, returning to step S1;

[0011] S4, the fan of the cooling tower runs at the rated speed, and determines whether the first-order derivative change of the temperature T1 in the adjacent collection period is greater than the third target threshold; if so, go to step S5; if not, return to step S1;

[0012] S5, recollecting the temperature T1 of the outlet of the coolant of the liquid cooling cabinet and determining whether the temperature T1 is greater than the target temperature threshold; if so, proceeding to step S6; if not, returning to step S1;

[0013] S6. The liquid pump operates at the maximum frequency or at the sum of the rated frequency and the predetermined frequency addition amount, the water pump operates at the maximum frequency or at the sum of the rated frequency and the predetermined frequency addition amount, the cooling tower fan operates at the limit frequency, the cooling tower water pump operates at the limit frequency, and then returns to step S1.

[0014] As a preferred solution, in step S1, the first preset target condition is: the liquid pump operates at a rated frequency, the water pump operates at a rated frequency, the cooling tower fan operates at a maximum frequency, and the cooling tower water pump operates at a maximum frequency.

[0015] As a preferred solution, the first preset threshold is 25-40°C, the first target threshold is 0.1-0.5, the second target threshold is 0-10, and the third target threshold is 0-0.6; the temperature threshold A is 20-30°C and is less than the first preset threshold; the target temperature threshold is 40-55°C.

[0016] As a preferred solution, in step S1, if the ambient temperature T0 is between the second preset threshold and the first preset threshold, the liquid pump, the water pump and the cooling tower are operated according to the second preset target condition, and the process goes to step S20; wherein the second preset threshold is less than the first preset threshold;

[0017] S20, detecting the temperature T1 of the outlet of the cooling liquid of the liquid cooling cabinet, and determining whether the temperature (T1-A) / T0 is greater than a fourth target threshold; if so, proceeding to step S30; if not, returning to step S1;

[0018] S30, determine whether the temperature integral median of T1-T0 within the target time period is greater than the fifth target threshold; if so, go to step S40; if not, increase the cooling tower fan speed by (T1-T0)*F1 / F r *100+200, then return to step S1; where F1 is the actual operating frequency of the water pump, F r is the rated frequency of the pump;

[0019] S40, cooling tower fan speed increase (T1-T0)*F1 / F r *100, and determine whether the first-order derivative change of the temperature T1 in the adjacent acquisition period is greater than the sixth target threshold; if so, go to step S50; if not, return to step S1;

[0020] S50, the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the maximum frequency, the cooling tower water pump operates at the maximum frequency, and then returns to step S1.

[0021] As a preferred solution, the second preset target condition is: the liquid pump operates at a rated frequency, the water pump operates at a rated frequency, the cooling tower fan operates at a rated frequency, and the cooling tower water pump operates at a rated frequency.

[0022] As a preferred solution, the second preset threshold is 20-30° C., the fourth target threshold is 0.5-1, the fifth target threshold is 5-35, and the sixth target threshold is 0-0.6.

[0023] As a preferred solution, in step S1, if the ambient temperature T0 is not greater than the second preset threshold value, the liquid pump, the water pump and the cooling tower are operated according to the third preset target condition, and the process goes to step S200;

[0024] S200, detecting the temperature T1 of the outlet of the cooling liquid of the liquid cooling cabinet, and determining whether the temperature (T1-A) / T0 is greater than the seventh target threshold; if so, proceeding to step S300; if not, returning to step S1;

[0025] S300, determine whether the temperature integral median of T1-T0 within the target time period is greater than the eighth target threshold; if so, go to step S400; if not, increase the cooling tower fan speed by (T1-T0)*F1 / F r *100, then return to step S1; where F1 is the actual operating frequency of the water pump, F r is the rated frequency of the pump;

[0026] S400, cooling tower fan speed increase (T1-T0)*F1 / F r *100+200, and determine whether the first-order derivative change of the temperature T1 in the adjacent acquisition period is greater than the ninth target threshold; if so, go to step S500; if not, return to step S1;

[0027] S500, the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the maximum frequency, the cooling tower water pump operates at the maximum frequency, and then returns to step S1.

[0028] As a preferred solution, the third preset target condition is: the liquid pump runs at the lowest frequency, the water pump runs at the lowest frequency, the cooling tower fan runs at the lowest frequency, and the cooling tower water pump runs at the lowest frequency.

[0029] As a preferred solution, the seventh target threshold is 1-10, the eighth target threshold is 10-40, and the ninth target threshold is 0-0.8.

[0030] The present invention also provides a high-load control system for container data center cooling equipment, which uses the high-load control method described in any of the above solutions, and the high-load control system includes:

[0031] The acquisition module is used to acquire the ambient temperature T0, the temperature T1, the median of the temperature integral of T1-T0 in the target time period, and the first-order derivative change of the temperature T1 in adjacent acquisition cycles;

[0032] A judgment module, used to perform the judgment step in the high load control method to obtain a corresponding judgment result;

[0033] The execution module is used to execute corresponding subsequent steps according to the judgment result.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The present invention determines the heat load change of the server in the liquid cooling cabinet by the outlet temperature of the coolant of the liquid cooling cabinet (referred to as the liquid side outlet temperature), and uses it as feedback to intelligently control the liquid pump, water pump, cooling tower fan, and cooling tower water pump, thereby realizing the safe operation of the container data center;

[0036] (2) Through the setting of the ambient temperature threshold, the liquid side outlet temperature threshold and the secondary judgment of the first-order derivative of the liquid side outlet temperature, the load condition, load change condition and feedback condition of the liquid side are accurately identified, and a fast response adjustment control system is achieved;

[0037] (3) By setting the threshold of ambient temperature, targeted control can be achieved in different environments and scenarios, making the control of the container data center more applicable and avoiding abnormalities;

[0038] (4) Through periodic cycle detection and judgment, online and timely detection and control of the container data center can be achieved, which improves the effectiveness and timely feedback of intelligent control. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is a schematic diagram of a liquid cooling system according to Embodiment 1 of the present invention;

[0040] Figure 2 is a flow chart of a high load control method for a container data center cooling device according to Embodiment 1 of the present invention;

[0041] Figure 3 This is a module architecture diagram of a high-load control system for a container data center cooling device according to Embodiment 1 of the present invention. DETAILED DESCRIPTION

[0042] In order to more clearly illustrate the embodiments of the present invention, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other accompanying drawings and other implementation methods can be obtained based on these accompanying drawings without creative work.

[0043] Embodiment 1:

[0044] like Figure 1 As shown, the container data center cooling equipment of this embodiment includes a liquid cooling cabinet (i.e., a Tank cabinet), a heat exchanger, and a cooling tower. Among them, the liquid side inlet and the liquid side outlet of the heat exchanger are respectively connected to the inlet and outlet of the cooling liquid of the liquid cooling cabinet to form a circulating flow path of the cooling liquid (referred to as the liquid path), and the circulating flow path of the cooling liquid is provided with a liquid pump; the water side inlet and the water side outlet of the heat exchanger are respectively connected to the water outlet and the water inlet of the cooling tower to form a circulating flow path of the cooling water (referred to as the water path), and the circulating flow path of the cooling water is provided with a water pump.

[0045] The cooling water and the coolant are used to exchange heat to realize the circulating liquid cooling function of the coolant.

[0046] like Figure 2 As shown, the high load control method of the container data center cooling equipment of this embodiment includes the following steps:

[0047] S0, start running;

[0048] S1. Collect (i.e. detect) the ambient temperature T0 and determine whether the ambient temperature T0 reaches the first preset threshold value B; if so, the liquid pump, water pump and cooling tower operate according to the first preset target conditions, and go to step S2; wherein the first preset threshold value B is 25-40°C, and the example is 35°C.

[0049] Specifically, the first preset target condition is: the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the maximum frequency, and the cooling tower water pump operates at the maximum frequency.

[0050] S2. Collect the temperature T1 of the outlet of the cooling liquid of the liquid cooling cabinet (referred to as the liquid pool outlet temperature T1), and judge whether the temperature (T1-A) / T0 is greater than the first target threshold M3, that is, judge if (f(T1-A) / T0>M3,0,1), the range of the first target threshold M3 is 0.1-0.5, and the example is 0.1; if yes (that is, the value is 1), go to step S3; if not (that is, the value is 0), return to step S1; the temperature threshold A is 20-30°C, and is less than the first preset threshold;

[0051] S3, judging whether the temperature integral median of T1-T0 in the target time period is greater than the second target threshold, that is, judging if(1 / (ba)*∫f(x)dx)>N3,0,1), the second target threshold N3 is 0-10, and the example is 5; if yes, go to step S4; if no, return to step S1;

[0052] S4, the fan of the cooling tower runs at the rated speed, and determines whether the first-order derivative change of the temperature T1 in the adjacent collection period is greater than the third target threshold Z (i.e., if (f(f(T1))>Z, 0, 1)), the third target threshold Z is 0-0.6, 0.05 in the example, and the collection period is 20s; if so, go to step S5; if not, return to step S1;

[0053] S5, recollect the temperature T1 of the outlet of the coolant of the liquid cooling cabinet and determine whether the temperature T1 is greater than the target temperature threshold W, W is 40-55°C, and is 52°C in the example; if so, go to step S6; if not, return to step S1;

[0054] S6. It indicates that the load of the IT server in the liquid cooling cabinet increases rapidly, the liquid pump runs at the maximum frequency or at the sum of the rated frequency and the predetermined frequency addition (for example, 10 Hz, which can be determined according to the actual application requirements), the water pump runs at the maximum frequency or at the sum of the rated frequency and the predetermined frequency addition (for example, 10 Hz, which can be determined according to the actual application requirements), the cooling tower fan runs at the limit frequency, and the cooling tower water pump runs at the limit frequency, and then returns to step S1.

[0055] In addition, in step S1, if the ambient temperature T0 is between the second preset threshold value A and the first preset threshold value B, the liquid pump, the water pump and the cooling tower operate according to the second preset target conditions, and proceed to step S20; wherein the second preset threshold value A is less than the first preset threshold value B, and the second preset threshold value A (same as the temperature threshold value A) is 20 to 30°C, and the example is 20°C.

[0056] Specifically, the second preset target condition is: the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the rated frequency, and the cooling tower water pump operates at the rated frequency.

[0057] S20, detecting the temperature T1 of the outlet of the coolant of the liquid cooling cabinet, and determining whether the temperature (T1-A) / T0 is greater than the fourth target threshold M2, that is, determining if (f(T1-A) / T0>M2,0,1), the range of the fourth target threshold M2 is 0.5-1, and the example is 0.8; if so, go to step S30; if not, return to step S1;

[0058] S30, judging whether the temperature integral median of T1-T0 in the target time period is greater than the fifth target threshold value N2, that is, judging if (1 / (ba)*∫f(x)dx)>N2, 0, 1), the fifth target threshold value N2 is 5-35, and the example is 15; if so, go to step S40; if not, it means that the IT server load increases rapidly, and the speed of the cooling tower fan increases by (T1-T0)*F1 / Fr*100+200, and then returns to step S1; wherein F1 is the actual operating frequency of the water pump, and Fr is the rated frequency of the water pump;

[0059] S40, indicating that the load of the IT server increases rapidly, the speed of the cooling tower fan increases by (T1-T0)*F1 / Fr*100, and judging whether the first-order derivative change of the temperature T1 in the adjacent collection period is greater than the sixth target threshold value Y (i.e. if (f(f(T1))>Y, 0, 1)), the sixth target threshold value Y is 0-0.6, and the example is 0.05, and the collection period is 20s; if so, go to step S50; if not, return to step S1;

[0060] S50, indicating that the IT server load increases rapidly, the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the maximum frequency, and the cooling tower water pump operates at the maximum frequency, and then returns to step S1.

[0061] In addition, in step S1, if the ambient temperature T0 is not greater than the second preset threshold value A, the liquid pump, the water pump and the cooling tower are operated according to the third preset target condition, and the process goes to step S200;

[0062] Specifically, the third preset target condition is: the liquid pump operates at the lowest frequency, the water pump operates at the lowest frequency, the cooling tower fan operates at the lowest frequency, and the cooling tower water pump operates at the lowest frequency.

[0063] S200, detecting the temperature T1 of the outlet of the coolant of the liquid cooling cabinet, and determining whether the temperature (T1-A) / T0 is greater than the seventh target threshold M1, that is, determining if (f(T1-A) / T0>M1,0,1), the seventh target threshold M1 ranges from 1 to 10, and is 1 in the example; if so, go to step S300; if not, return to step S1;

[0064] S300, judging whether the temperature integral median of T1-T0 in the target time period is greater than the eighth target threshold value N1, that is, judging if (1 / (ba)*∫f(x)dx)>N1, 0, 1), the eighth target threshold value N1 is 10-40, and the example is 22; if so, go to step S400; if not, it means that the IT server load increases rapidly, and the speed of the cooling tower fan increases by (T1-T0)*F1 / Fr*100, and then returns to step S1; wherein F1 is the actual operating frequency of the water pump, and Fr is the rated frequency of the water pump;

[0065] S400, indicating that the load of the IT server increases rapidly, the speed of the cooling tower fan increases by (T1-T0)*F1 / Fr*100+200, and judging whether the first-order derivative change of the temperature T1 in the adjacent collection period is greater than the ninth target threshold value X (i.e. if(f(f(T1))>X,0,1)), the ninth target threshold value X is 0-0.8, 0.1 in the example, and the collection period is 20s; if so, go to step S500; if not, return to step S1;

[0066] S500, indicating that the IT server load increases rapidly, the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the maximum frequency, and the cooling tower water pump operates at the maximum frequency, and then returns to step S1.

[0067] Corresponding to the high load control method of the container data center cooling equipment in the present embodiment, as shown in FIG. Figure 3 As shown, this embodiment also provides a high-load control system for container data center cooling equipment, including a setting module, a collection module, a judgment module and an execution module.

[0068] Among them, the setting module is used to set all thresholds, which is convenient for freely adjusting the threshold settings.

[0069] The acquisition module is used to collect the ambient temperature T0, temperature T1, the median of the temperature integral of T1-T0 in the target time period, and the first-order derivative change of the temperature T1 in adjacent acquisition cycles;

[0070] The judgment module is used to execute each judgment step in the above control method to obtain a corresponding judgment result;

[0071] The execution module is used to execute corresponding subsequent steps according to the judgment result.

[0072] The specific execution process of the above modules can refer to the detailed description of the above high load control method, which will not be repeated here.

[0073] The above description is only a detailed description of the preferred embodiments and principles of the present invention. For ordinary technicians in this field, according to the ideas provided by the present invention, there will be changes in the specific implementation methods, and these changes should also be regarded as the protection scope of the present invention.

Claims

1. A high-load control method for a container data center cooling device, wherein the container data center cooling device comprises a liquid cooling cabinet, a heat exchanger and a cooling tower, wherein the liquid side inlet and the liquid side outlet of the heat exchanger are respectively connected to the inlet and the outlet of the cooling liquid of the liquid cooling cabinet to form a circulation flow path of the cooling liquid, and the circulation flow path of the cooling liquid is provided with a liquid pump; the water side inlet and the water side outlet of the heat exchanger are respectively connected to the water outlet and the water inlet of the cooling tower to form a circulation flow path of the cooling water, and the circulation flow path of the cooling water is provided with a water pump, wherein the method is characterized in that: The high load control method comprises the following steps: S1, collecting the ambient temperature and determining whether the ambient temperature T0 reaches a first preset threshold; if so, the liquid pump, the water pump and the cooling tower operate according to the first preset target conditions, and go to step S2; S2, collecting the temperature T1 of the outlet of the cooling liquid of the liquid cooling cabinet, and determining whether the temperature (T1-A) / T0 is greater than the first target threshold; if so, proceeding to step S3; if not, returning to step S1; wherein A is the temperature threshold; S3, determining whether the temperature integral median of T1-T0 within the target time period is greater than the second target threshold; if so, proceeding to step S4; if not, returning to step S1; S4, the fan of the cooling tower runs at the rated speed, and determines whether the first-order derivative change of the temperature T1 in the adjacent collection period is greater than the third target threshold; if so, go to step S5; if not, return to step S1; S5, recollecting the temperature T1 of the outlet of the coolant of the liquid cooling cabinet and determining whether the temperature T1 is greater than the target temperature threshold; if so, proceeding to step S6; if not, returning to step S1; S6, the liquid pump operates at the maximum frequency or at the sum of the rated frequency and the predetermined frequency addition amount, the water pump operates at the maximum frequency or at the sum of the rated frequency and the predetermined frequency addition amount, the cooling tower fan operates at the limit frequency, and the cooling tower water pump operates at the limit frequency, and then returns to step S1; In step S1, the first preset target condition is: the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the maximum frequency, and the cooling tower water pump operates at the maximum frequency; The first preset threshold is 25-40°C, the first target threshold is 0.1-0.5, the second target threshold is 0-10, and the third target threshold is 0-0.6; the temperature threshold A is 20-30°C and is less than the first preset threshold; the target temperature threshold is 40-55°C.

2. The high load control method for cooling equipment of a container data center according to claim 1, characterized in that: In the step S1, if the ambient temperature T0 is between the second preset threshold and the first preset threshold, the liquid pump, the water pump and the cooling tower are operated according to the second preset target condition, and the process goes to step S20; wherein the second preset threshold is less than the first preset threshold; S20, detecting the temperature T1 of the outlet of the cooling liquid of the liquid cooling cabinet, and determining whether the temperature (T1-A) / T0 is greater than a fourth target threshold; if so, proceeding to step S30; if not, returning to step S1; S30, determine whether the temperature integral median of T1-T0 within the target time period is greater than the fifth target threshold; if so, go to step S40; if not, increase the speed of the cooling tower fan by (T1-T0)*F1 / F r *100+200, then return to step S1; where F1 is the actual operating frequency of the water pump, F r is the rated frequency of the pump; S40, cooling tower fan speed increase (T1-T0) * F1 / F r *100, and determine whether the first-order derivative change of the temperature T1 in the adjacent acquisition period is greater than the sixth target threshold; if so, go to step S50; if not, return to step S1; S50, the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the maximum frequency, and the cooling tower water pump operates at the maximum frequency, and then returns to step S1; The second preset target condition is: the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the rated frequency, and the cooling tower water pump operates at the rated frequency; The second preset threshold is 20-30° C., the fourth target threshold is 0.5-1, the fifth target threshold is 5-35, and the sixth target threshold is 0-0.

6.

3. The high load control method for cooling equipment of a container data center according to claim 2, characterized in that: In step S1, if the ambient temperature T0 is not greater than the second preset threshold, the liquid pump, the water pump and the cooling tower are operated according to the third preset target condition, and the process goes to step S200; S200, detecting the temperature T1 of the outlet of the coolant of the liquid cooling cabinet, and determining whether the temperature (T1-A) / T0 is greater than a seventh target threshold; If yes, go to step S300; if no, return to step S1; S300, determine whether the temperature integral median of T1-T0 in the target time period is greater than the eighth target threshold; if so, go to step S400; if not, increase the speed of the cooling tower fan by (T1-T0)*F1 / F r *100, then return to step S1; where F1 is the actual operating frequency of the water pump, F r is the rated frequency of the pump; S400, cooling tower fan speed increase (T1-T0) * F1 / F r *100+200, and determine whether the first-order derivative change of the temperature T1 in the adjacent acquisition period is greater than the ninth target threshold; if so, go to step S500; if not, return to step S1; S500, the liquid pump operates at the rated frequency, the water pump operates at the rated frequency, the cooling tower fan operates at the maximum frequency, and the cooling tower water pump operates at the maximum frequency, and then returns to step S1; The third preset target condition is: the liquid pump operates at the lowest frequency, the water pump operates at the lowest frequency, the cooling tower fan operates at the lowest frequency, and the cooling tower water pump operates at the lowest frequency; The seventh target threshold is 1-10, the eighth target threshold is 10-40, and the ninth target threshold is 0-0.

8.

4. A high load control system for cooling equipment in a container data center, using the high load control method according to any one of claims 1 to 3, characterized in that: The high load control system comprises: The acquisition module is used to acquire the ambient temperature T0, the temperature T1, the median of the temperature integral of T1-T0 in the target time period, and the first-order derivative change of the temperature T1 in adjacent acquisition cycles; A judgment module, used to perform the judgment step in the high load control method to obtain a corresponding judgment result; The execution module is used to execute corresponding subsequent steps according to the judgment result.

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