A method, system, medium and equipment for optimizing pressure of air compression station

Abstract

The present invention discloses a method, system, medium and equipment for optimizing the pressure of an air compressor station, comprising the following steps: obtaining the current outlet pressure and the current outlet flow of the air compressor station; reading the status and operation data of each air compressor; outputting an actual pressure signal of the outlet of the air compressor station to each variable frequency air compressor, and each variable frequency air compressor operates according to the actual outlet pressure of the air compressor station; reading the actual outlet pressure and actual flow of the air compressor station in each pressure sampling cycle, outputting the actual outlet pressure of the air compressor station to the variable frequency air compressor, and making each variable frequency air compressor operate according to the actual outlet pressure of the air compressor station, and calculating the variation derivative and control time of the outlet pressure of the air compressor station; setting at least one threshold value, and controlling the operation of each air compressor according to the above parameters to optimize the outlet pressure; the air compressor station pressure optimization method can make the outlet pressure fluctuation of the air compressor station smaller, and make the variable frequency air compressor more fully exert the advantages of pressure regulation, so as to make the operation efficiency of the air compressor station higher.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure design of an air compressor station in which fixed-frequency air compressors and variable-frequency air compressors are mixed, and in particular to an air compressor station pressure optimization method, system, medium and equipment. Background Art

[0002] With the advancement of automation technology, air compressor stations are equipped with joint control systems. The joint control system monitors the changes in the outlet pressure of the air compressor station and controls the number of air compressors put into use, which can reduce the fluctuation of the outlet pressure of the air compressor station and improve the operating efficiency of the air compressor station.

[0003] However, the traditional air compressor station joint control system has the following problems: the joint control system monitors the changes in the outlet pressure of the air compressor station, and only controls the air compressor to operate when the outlet pressure of the air compressor station changes beyond the set range. Since the input or output of the air compressor requires action time, the air compressor will frequently load and unload when the outlet pressure of the air compressor station changes drastically, and the outlet pressure of the air compressor station will also exceed the set limit range; due to the design of the station house pipeline, the outlet pressure of the air compressor station is quite different from the outlet pressure of the variable frequency air compressor. In many cases, the variable frequency air compressor is difficult to give full play to the advantages of pressure regulation, resulting in a large number of air compressors being put into use, which reduces the operating efficiency of the air compressor station. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide an air compressor station pressure optimization method, system, medium and equipment.

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

[0006] In a first aspect, an embodiment of the present disclosure provides a method for optimizing pressure of an air compressor station, comprising the following steps:

[0007] Get the current air compressor station outlet pressure and current air compressor station outlet flow;

[0008] Read the status and operation data of each air compressor;

[0009] Output the actual pressure signal of the air compression station outlet to each variable frequency air compressor, and each variable frequency air compressor operates according to the actual pressure of the air compression station outlet;

[0010] The actual pressure and flow rate at the outlet of the air compressor station are read in each pressure sampling cycle, and the actual pressure at the outlet of the air compressor station is output to the variable frequency air compressor, so that each variable frequency air compressor operates according to the actual pressure at the outlet of the air compressor station, and the change derivative and control time of the pressure at the outlet of the air compressor station are calculated;

[0011] At least one threshold is set, and the operation of each air compressor is controlled in combination with the variation derivative, control time, current air compressor station outlet pressure, current air compressor station outlet flow, air compressor status and operation data to optimize the outlet pressure.

[0012] In a second aspect, an embodiment of the present disclosure provides an air compressor station pressure optimization system for mixing fixed-frequency air compressors and variable-frequency air compressors, comprising:

[0013] The processing device is used to store the number of air compressors in the air compressor station, the rated pressure of the power frequency air compressor, the rated gas output of the power frequency air compressor, the rated pressure of the variable frequency air compressor, the rated gas output of the variable frequency air compressor, the lower limit of the load rate of the variable frequency air compressor and the compressed air outlet target pressure, and is also used for the staff to set the fluctuation range of the air compressor station outlet target pressure, the pressure sampling cycle, the air compressor start delay time, the air compressor loading delay time, the default start and stop sequence of the air compressor and the long-term shutdown time, and is also used to read the start and stop status of the unit and to record the current loading time of each air compressor;

[0014] An air compression station outlet pressure sensor, used to detect pressure information and feed it back to the processing device; and

[0015] The outlet flow meter of the air compressor station is used to detect the flow information and feed it back to the processing device.

[0016] The processing device adopts the following working method:

[0017] Get the current air compressor station outlet pressure and current air compressor station outlet flow;

[0018] Read the status and operation data of each air compressor;

[0019] Output the actual pressure signal of the air compression station outlet to each variable frequency air compressor, and each variable frequency air compressor operates according to the actual pressure of the air compression station outlet;

[0020] The actual pressure and flow rate at the outlet of the air compressor station are read in each pressure sampling cycle, and the actual pressure at the outlet of the air compressor station is output to the variable frequency air compressor, so that each variable frequency air compressor operates according to the actual pressure at the outlet of the air compressor station, and the change derivative and control time of the pressure at the outlet of the air compressor station are calculated;

[0021] At least one threshold is set, and the operation of each air compressor is controlled according to the variation derivative, control time, current air compressor station outlet pressure, current air compressor station outlet flow, air compressor state and operation data to optimize the outlet pressure.

[0022] In a third aspect, an embodiment of the present disclosure provides a non-volatile tangible storage medium having computer executable instructions stored thereon, wherein the computer executable instructions, when executed by a computer, enable the computer to execute the above-mentioned air compression station pressure optimization method.

[0023] In a fourth aspect, an embodiment of the present disclosure provides an air compressor station pressure optimization device using a fixed frequency air compressor and a variable frequency air compressor, including:

[0024] at least one processor; and

[0025] At least one memory, wherein the at least one memory stores computer executable code, and when the computer executable code is run by the at least one processor, it executes the above-mentioned air compression station pressure optimization method.

[0026] At least one of the above technical solutions adopted in the embodiments of this specification can achieve the following beneficial effects: reduce the outlet pressure fluctuation of the air compressor station, allow the variable frequency air compressor to give full play to the advantages of pressure regulation, and make the operation efficiency of the air compressor station higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 The present invention is a flow chart of a method for optimizing pressure of an air compressor station.

[0029] Figure 2 The invention provides a structural schematic diagram of an air compressor station pressure optimization system that uses a mixture of fixed-frequency air compressors and variable-frequency air compressors. DETAILED DESCRIPTION

[0030] The various preferred embodiments of the present invention will be described below with reference to the accompanying drawings. The following description with reference to the accompanying drawings is provided to assist in the understanding of the exemplary embodiments of the present invention as defined by the claims and their equivalents. It includes various specific details to assist in understanding, but they are to be viewed as exemplary only. Therefore, those skilled in the art will recognize that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present invention. Moreover, in order to make the specification more clear and concise, detailed descriptions of functions and configurations well known in the art will be omitted.

[0031] Reference Figure 1 As shown, a method for optimizing pressure of an air compressor station comprises the following steps:

[0032] S1. Pre-store the number of air compressors in the air compression station, the rated pressure of the power frequency air compressor, the rated gas output of the power frequency air compressor, the rated pressure of the variable frequency air compressor, the rated gas output of the variable frequency air compressor, the lower limit of the load rate of the variable frequency air compressor and the target pressure of the compressed air outlet;

[0033] S2. Set the fluctuation range of the target pressure at the outlet of the air compressor station, the pressure sampling period, the air compressor start delay time, the air compressor loading delay time, the default start and stop sequence and the air compressor long-term shutdown time, and read the start and stop status of the unit and the lower limit of the variable frequency air compressor load rate;

[0034] S3. Calculate the actual flow rate of each air compressor and the lower limit of the flow rate of the frequency converter according to the target pressure at the outlet of the air compressor station, and detect the actual pressure at the outlet of the air compressor station and the actual flow rate at the outlet of the air compressor station; wherein, the calculation method of the actual flow rate and the lower limit of the flow rate of the frequency converter is:

[0035] The relationship between the pressure, temperature, and volume of compressed air follows the gas state equation:

[0036] pV=nRT1

[0037] Where p is the pressure of the gas, in kgf / m 3 ; V is the gas volume, in m 3 ; n is the amount of substance; T1 is the absolute temperature, in K; R represents the gas constant;

[0038] For air compressors, when compressing the same volume of air and ignoring changes in gas temperature, the changes in pressure and volume after compression are inversely proportional:

[0039] p 额定 Q 额定 =p 实际 Q 实际

[0040] Where p 额定 Q is the rated gas pressure of the air compressor. 额定 is the gas flow rate at the rated pressure of the air compressor, p 实际 is the actual gas production pressure of the air compressor, Q 实际 It is the gas flow rate produced by the air compressor under actual pressure;

[0041] The lower limit of the flow rate of the variable frequency air compressor is:

[0042] Q min =Q 实际 R v

[0043] The lower limit of flow is the flow rate under actual pressure * minimum load rate;

[0044] S4. Output the actual pressure signal of the air compressor station outlet to each inverter. Each inverter operates according to the actual pressure signal of the air compressor station outlet, reads the start and stop status, loading and unloading status, and load rate of each air compressor, and records the current loading time of each air compressor;

[0045] S5. Read the actual pressure and flow rate at the outlet of the air compressor station in each pressure sampling cycle, output the actual pressure at the outlet of the air compressor station to the variable frequency air compressor, and calculate the change derivative P' of the outlet pressure of the air compressor station, the difference △P between the outlet pressure fluctuation and the upper or lower limit of the target pressure, and calculate the control time T2 according to the formula T=△P / P'. Control the operation of each air compressor according to the change derivative, control time, current outlet pressure of the air compressor station, current outlet flow rate of the air compressor station, air compressor status and operating data to optimize the outlet pressure, where P'=the difference between the current outlet pressure and the outlet pressure of the previous second.

[0046] Specific optimization method A: When the outlet pressure of the air compressor station is less than the target pressure of the compressed air outlet - the difference between the fluctuation range of the target pressure of the air compressor station outlet, and the variation derivative is ≤0, add one air compressor for every air compressor start-up delay time until the actual outlet pressure of the air compressor station is greater than the target pressure of the compressed air outlet - the difference between the fluctuation range of the target pressure of the air compressor station outlet.

[0047] Among them, when adding air compressors, priority should be given to adding variable frequency air compressors.

[0048] Specific optimization method B: When the outlet pressure of the air compressor station is greater than the compressed air outlet target pressure + the sum of the fluctuation range of the air compressor station outlet target pressure, and the variation derivative is ≥ 0, one air compressor is reduced for every air compressor loading delay time until the outlet pressure of the air compressor station is less than the compressed air outlet target pressure + the sum of the fluctuation range of the air compressor station outlet target pressure.

[0049] Among them, when reducing air compressors, priority should be given to reducing industrial frequency air compressors.

[0050] Specific optimization method C: When the actual pressure at the air compressor station outlet is within the difference between the compressed air outlet target pressure and the air compressor station outlet target pressure fluctuation range or the sum of the compressed air outlet target pressure and the air compressor station outlet target pressure fluctuation range, and the control time is less than the air compressor start-up delay time or the air compressor loading delay time, read the actual flow rate at the air compressor station outlet, and calculate the maximum flow rate and the minimum flow rate of the air compressor currently being loaded and running according to the current actual pressure at the air compressor station outlet, where the maximum flow rate = Q 实际 , minimum flow = Q 实际 R v .

[0051] Exemplarily, if the variation derivative is less than 0, and the maximum flow of the air compressor being loaded is less than the current actual flow at the outlet of the air compressor station, it indicates that the total flow of the currently loaded air compressors can no longer meet the demand. When the control time is less than the air compressor start-up delay time, a pressure signal lower than the outlet pressure of the air compressor station is output to the variable frequency air compressor whose current load rate has not reached 100%, and an additional air compressor is started in accordance with the air compressor start-up sequence. When the control time is greater than the air compressor start-up delay time, the current outlet pressure signal of the air compressor station is output for the operation of each variable frequency air compressor. Exemplarily, a pressure signal 20% lower than the outlet pressure of the air compressor station can be output.

[0052] For example, if the variation derivative is less than 0, and the maximum flow of the air compressor being loaded is greater than the current actual flow at the outlet of the air compressor station, it indicates that the air compressor currently being loaded is not running at full load. When the control time is less than the air compressor loading delay time, a pressure signal lower than the outlet pressure of the air compressor station is output to the frequency converter whose current load rate has not reached 100%. When the control time is greater than the air compressor loading delay time, the current outlet pressure of the air compressor station is output to each variable frequency air compressor for operation; for example, a pressure signal 20% lower than the outlet pressure of the air compressor station can be output.

[0053] For example, if the variation derivative is greater than 0, and the minimum flow rate of the air compressor being loaded is greater than the current actual flow rate at the outlet of the air compressor station, it indicates that the lowest load of the air compressor currently being loaded is greater than the current gas demand. When the control time is less than the air compressor loading delay time, unload one industrial frequency air compressor in the start-stop sequence. If there is no industrial frequency air compressor currently running, stop one variable frequency air compressor.

[0054] For example, if the variation derivative is greater than 0, and the minimum flow of the air compressor being loaded is less than the current actual flow at the outlet of the air compressor station, when the control time is less than the air compressor loading delay time, a pressure signal higher than the actual pressure at the outlet of the air compressor station is output to the frequency converter whose current load rate has not reached the lower limit of the load rate, so that the frequency converter air compressor can quickly reduce the load rate. When the control time is greater than the air compressor loading delay time, the current air compressor station outlet pressure signal is output to each frequency converter air compressor as a basis for operation.

[0055] S6. If the unloading time of the industrial frequency air compressor currently in unloading operation exceeds the idle long downtime, it will be shut down.

[0056] like Figure 2 As shown, the embodiment of the present disclosure also provides an air compression station pressure optimization system that uses a mixture of fixed-frequency air compressors and variable-frequency air compressors, including: a processing device 10, an air compression station outlet pressure sensor 11, and an air compression station outlet flow meter 12.

[0057] The processing device is used to store the number of air compressors in the air compressor station, the rated pressure of the industrial frequency air compressor, the rated gas output of the industrial frequency air compressor, the rated pressure of the variable frequency air compressor, the rated gas output of the variable frequency air compressor, the lower limit of the variable frequency air compressor load rate and the compressed air outlet target pressure; the processing device is also used for the staff to set the fluctuation range of the air compressor station outlet target pressure, the pressure sampling period, the air compressor start delay time, the air compressor loading delay time, the default start and stop sequence of the air compressor, the long-term downtime and two thresholds; the processing device is also used to read the start and stop status of the unit, and to record the current loading time of each air compressor; the outlet of the variable frequency air compressor is also provided with a pressure sensor (not shown). The processing device performs the following method:

[0058] Read the status and operation data of each air compressor, output the actual pressure signal of the air compressor station outlet to each variable frequency air compressor, and each air compressor operates according to the actual pressure of the air compressor station outlet;

[0059] The actual pressure and flow rate at the outlet of the air compressor station are read in each pressure sampling cycle, and the actual pressure at the outlet of the air compressor station is output to the variable frequency air compressor, so that each variable frequency air compressor operates according to the actual pressure at the outlet of the air compressor station, and the change derivative and control time of the pressure at the outlet of the air compressor station are calculated;

[0060] According to the threshold, fluctuation range of the target pressure at the air compressor station outlet, variation derivative, current air compressor station outlet pressure, inverter flow lower limit and control time, each air compressor is controlled to optimize the outlet pressure;

[0061] If the unloading time of the industrial frequency air compressor currently in unloading operation exceeds the idle long downtime, it will be shut down.

[0062] Specifically, the methods for optimizing the outlet pressure include:

[0063] Method A: When the outlet pressure of the air compressor station is less than at least one threshold value and the variation derivative is ≤0, one air compressor is added for every air compressor start-up delay time until the outlet pressure of the air compressor station is greater than the at least one threshold value;

[0064] Method B: when the outlet pressure of the air compressor station is greater than at least one threshold value and when the variation derivative is ≥ 0, one air compressor is reduced for every air compressor loading delay time until the outlet pressure of the air compressor station is less than the at least one threshold value;

[0065] Method C: When the outlet pressure of the air compressor station is at at least one threshold value and the control time is less than the air compressor start-up delay time or the air compressor loading delay time, the current actual flow rate at the outlet of the air compressor station is read, and the maximum flow rate and the minimum flow rate of the air compressor currently being loaded are calculated according to the current actual pressure. Then, each air compressor is controlled according to the variation derivative, the current load rate of the variable frequency air compressor, the lower limit of the load rate of the variable frequency air compressor, and the maximum flow rate and the minimum flow rate of the air compressor currently being loaded.

[0066] Specifically, when adding an air compressor in the method A, the variable frequency air compressor is configured to have a higher priority than the industrial frequency air compressor; when reducing an air compressor in the method B, the industrial frequency air compressor is configured to have a higher priority than the variable frequency air compressor.

[0067] Specifically, the threshold values ​​include: the difference between the compressed air outlet target pressure and the air compression station outlet target pressure fluctuation range; and the sum of the compressed air outlet target pressure and the air compression station outlet target pressure fluctuation range.

[0068] The embodiment of the present disclosure also provides a non-volatile tangible storage medium having computer executable instructions stored thereon, and when the computer program product is run on a terminal device, the terminal device can implement the above-mentioned air compression station pressure optimization method when executing it.

[0069] The disclosed embodiment also provides an air compressor station pressure optimization device that uses a mixture of fixed-frequency air compressors and variable-frequency air compressors, including: a processor and a memory, wherein the memory stores computer executable code, and when the computer executable code is executed by the processor, the above-mentioned air compressor station pressure optimization method can be implemented.

[0070] Finally, it should be noted that the above series of processing includes not only processing executed in time series in the order described here, but also processing executed in parallel or separately rather than in time series.

[0071] Through the description of the above implementation methods, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus the necessary hardware platform. Based on such an understanding, all or part of the contribution of the technical solution of the present invention to the background technology can be embodied in the form of a software product. The computer software product can be stored in a storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present invention or certain parts of the embodiments.

[0072] The present invention has been introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for optimizing pressure of an air compression station, characterized in that: The following steps are involved: Get the actual pressure and flow rate of the current air compressor station outlet; Read the status and operation data of each air compressor; Output the actual pressure signal of the air compression station outlet to each variable frequency air compressor, and each variable frequency air compressor operates according to the actual pressure of the air compression station outlet; The actual pressure and flow rate at the outlet of the air compressor station are read in each pressure sampling cycle, and the actual pressure at the outlet of the air compressor station is output to the variable frequency air compressor, so that each variable frequency air compressor operates according to the actual pressure at the outlet of the air compressor station, and the change derivative and control time of the pressure at the outlet of the air compressor station are calculated; At least one threshold is set, and the operation of each air compressor is controlled by combining the variation derivative, control time, current air compressor station outlet pressure, current air compressor station outlet flow, air compressor state and operation data to optimize the outlet pressure; The method for optimizing the outlet pressure specifically includes the following steps: Method A: when the outlet pressure of the air compressor station is less than the at least one threshold value and the variation derivative is ≤0, one air compressor is added for every air compressor start-up delay time until the outlet pressure of the air compressor station is greater than the at least one threshold value; Method B: when the outlet pressure of the air compressor station is greater than the at least one threshold value and when the variation derivative is ≥ 0, one air compressor is reduced for every air compressor loading delay time until the outlet pressure of the air compressor station is less than the at least one threshold value; Method C: when the outlet pressure of the air compressor station is at at least one of the threshold values ​​and the control time is less than the air compressor start-up delay time or the air compressor loading delay time, the current actual flow rate at the outlet of the air compressor station is read, and the maximum flow rate and the minimum flow rate of the air compressor currently being loaded are calculated according to the current actual pressure, and then each air compressor is controlled according to the variation derivative, the current load rate of the variable frequency air compressor, the lower limit of the load rate of the variable frequency air compressor, and the maximum flow rate and the minimum flow rate of the air compressor currently being loaded.

2. The method according to claim 1, characterized in that The status and operation data contain one or more of the number of air compressors in the air compression station, the rated pressure of the industrial frequency air compressor, the rated gas output of the industrial frequency air compressor, the rated pressure of the variable frequency air compressor, the rated gas output of the variable frequency air compressor, the lower limit of the variable frequency air compressor load rate, the compressed air outlet target pressure, the start and stop status, the current load rate of the variable frequency air compressor, the air compressor start delay time, the air compressor loading delay time, the default start and stop sequence of the air compressor and the long-term air shutdown time.

3. The method according to claim 2, characterized in that The following steps are also included: If the unloading time of the industrial frequency air compressor currently in unloading operation exceeds the idle long downtime, it will be shut down.

4. The method according to claim 3, characterized in that When adding an air compressor in method A, the variable frequency air compressor is configured to have a higher priority than the power frequency air compressor; When reducing the number of air compressors in the method B, the priority of the industrial frequency air compressor is configured to be higher than that of the variable frequency air compressor.

5. The method according to claim 3 or 4, characterized in that: The at least one threshold value includes: The difference between the compressed air outlet target pressure and the air compressor station outlet target pressure fluctuation range; and The sum of the compressed air outlet target pressure and the air compression station outlet target pressure fluctuation range.

6. A pressure optimization system for an air compressor station using a mixture of fixed-frequency air compressors and variable-frequency air compressors, characterized in that: include: A processing device, used to store and set the status and operation data of each air compressor, and the processing device is also configured to read the status and operation data of the unit; An air compression station outlet pressure sensor is used to detect pressure information and feed it back to the processing device; as well as An outlet flow meter of the air compressor station is used to detect flow information and feed it back to the processing device; The working method of the processing device comprises the following steps: Get the current air compressor station outlet pressure and current air compressor station outlet flow; Read the status and operation data of each air compressor; Output the actual pressure signal of the air compression station outlet to each variable frequency air compressor, and each variable frequency air compressor operates according to the actual pressure of the air compression station outlet; The actual pressure and flow rate at the outlet of the air compressor station are read in each pressure sampling cycle, and the actual pressure at the outlet of the air compressor station is output to the variable frequency air compressor, so that each variable frequency air compressor operates according to the actual pressure at the outlet of the air compressor station, and the change derivative and control time of the pressure at the outlet of the air compressor station are calculated; At least one threshold is set, and the operation of each air compressor is controlled by combining the variation derivative, control time, current air compressor station outlet pressure, current air compressor station outlet flow, air compressor state and operation data to optimize the outlet pressure; The method for optimizing the outlet pressure specifically includes the following steps: Method A: when the outlet pressure of the air compressor station is less than the at least one threshold value and the variation derivative is ≤0, one air compressor is added for every air compressor start-up delay time until the outlet pressure of the air compressor station is greater than the at least one threshold value; Method B: when the outlet pressure of the air compressor station is greater than the at least one threshold value and when the variation derivative is ≥ 0, one air compressor is reduced for every air compressor loading delay time until the outlet pressure of the air compressor station is less than the at least one threshold value; Method C: when the outlet pressure of the air compressor station is at at least one of the threshold values ​​and the control time is less than the air compressor start-up delay time or the air compressor loading delay time, the current actual flow rate at the outlet of the air compressor station is read, and the maximum flow rate and the minimum flow rate of the air compressor currently being loaded are calculated according to the current actual pressure, and then each air compressor is controlled according to the variation derivative, the current load rate of the variable frequency air compressor, the lower limit of the load rate of the variable frequency air compressor, and the maximum flow rate and the minimum flow rate of the air compressor currently being loaded.

7. A non-transitory tangible storage medium having computer executable instructions stored thereon, characterized in that: When the computer executable instructions are executed by a computer, the computer is caused to perform the method according to any one of claims 1 to 5.

8. A pressure optimization device for an air compression station using a mixture of fixed frequency air compressors and variable frequency air compressors, characterized in that: include: at least one processor; as well as At least one memory, wherein the at least one memory stores computer executable code, and when the computer executable code is executed by the at least one processor, the method according to any one of claims 1 to 5 is executed.

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