Air conditioner control method and air conditioner

Abstract

The invention provides an air conditioner control method and an air conditioner. According to the method, after a compressor is controlled to operate according to a PID control method, frequency change data of the compressor are recorded, whether the compressor enters a steady-state oscillation stage or not is judged according to the frequency change data, if yes, the compressor frequency in the steady-state oscillation stage is averaged, and the steady-state frequency fstep is obtained; and the frequency of the compressor is adjusted to be the steady-state frequency fstep for operation, so that frequent adjustment of the compressor is avoided, and energy consumption is reduced. In addition, due to the fact that the steady-state oscillation frequency is adopted for calculation, the accuracy of indoor temperature control is improved, and temperature fluctuation is reduced. And when the temperature is close to the target temperature, through a strategy of adjusting the frequency of the compressor to be the steady-state frequency fstep, rapid temperature fluctuation is avoided, and rapid and stable temperature response is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning control methods, and in particular to an air conditioning control method and an air conditioner. Background Art

[0002] PID (proportional, integral, differential) control is a classic industrial control system that adjusts the control quantity through three parameters: proportional (P), integral (I) and differential (D) to achieve the purpose of stabilizing the system output. Air conditioning load calculation involves the evaluation of the cooling or heating required by the air conditioning system under different environmental conditions.

[0003] In the prior art, air conditioning control mostly adopts a simple PID control strategy to maintain indoor temperature by adjusting the compressor frequency. However, these solutions usually lack accurate calculation and control of steady-state load, resulting in large frequency fluctuations of the compressor after reaching the set temperature, affecting energy efficiency and indoor comfort. The prior art does not combine steady-state load calculation to optimize the frequency control of the compressor, nor does it consider further calculating the actual load value by scientifically analyzing the compressor frequency changes generated during PID operation. Therefore, the prior art is insufficient in energy saving and temperature control accuracy. Summary of the invention

[0004] The purpose of the present invention is to overcome the above technical deficiencies and provide an air conditioning control method and an air conditioner to solve the problems in the related art that the air conditioning control has deficiencies in energy saving and temperature control accuracy.

[0005] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0006] According to a first aspect of the present invention, there is provided an air conditioning control method, comprising:

[0007] After the unit is started up for the first time, the compressor is controlled to run at the maximum frequency;

[0008] When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to the first threshold, the compressor is controlled to operate according to the PID control method;

[0009] After the compressor is controlled to run according to the PID control method, the frequency change data of the compressor is recorded;

[0010] According to the frequency change data, determining whether the compressor has entered a steady-state oscillation stage;

[0011] If yes, average the compressor frequency during the steady-state oscillation phase to obtain the steady-state frequency fsteady;

[0012] The compressor frequency is adjusted to the steady-state frequency fsteady for operation.

[0013] Preferably, the compressor frequency is adjusted to operate at the steady-state frequency fsteady, specifically:

[0014] When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to a second threshold, the compressor frequency is adjusted to the steady-state frequency fsteady for operation; the second threshold is less than the first threshold.

[0015] Preferably, the method further comprises:

[0016] Calculate the power value of the compressor and the power value of the fan under the steady-state frequency fsteady;

[0017] The sum of the power value of the compressor and the power value of the fan is taken as the steady-state power of the unit;

[0018] The steady-state frequency fsteady and the fan speed corresponding to the steady-state power are stored.

[0019] Preferably, the method further comprises:

[0020] After the unit is restarted, the compressor is controlled to run at the maximum frequency;

[0021] When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to the second threshold, the control unit is directly operated at the compressor frequency and fan speed corresponding to the steady-state power.

[0022] Preferably, the frequency change data of the recorded compressor is specifically:

[0023] The compressor frequency data is recorded once per second, and the data format includes:

[0024] Timestamp, current frequency, current temperature, target temperature, error.

[0025] Preferably, judging whether the compressor enters a steady-state oscillation stage according to the frequency change data includes:

[0026] Count the frequency changes of the compressor within a preset time and calculate the standard deviation σ;

[0027] If the standard deviation σ is less than the standard deviation threshold, it is determined that the compressor enters a steady-state oscillation stage.

[0028] Preferably, the fan speed is calculated according to the following formula (2), including:

[0029] Fan speed N f and compressor frequency f c The linear proportional relationship between: Nf = k·f c (2);

[0030] The proportionality coefficient k is adjusted according to specific system performance and design requirements.

[0031] Preferably, controlling the operation of the compressor according to the PID control method comprises:

[0032] Get the target temperature as T0, the current indoor temperature as T1, and the proportional gain Kp, integral gain Ki, and differential gain Kd set by the user;

[0033] Calculation error e(t) = T0-T1;

[0034] Calculate the PID output according to formula (1):

[0035]

[0036] Map the PID output u(t) to the compressor frequency f(t);

[0037] The compressor operation is controlled according to f(t).

[0038] Preferably, after controlling the operation of the compressor according to the PID control method, the method further comprises:

[0039] Monitor the indoor temperature T1 at preset intervals and recalculate the error e(t) and PID output u(t);

[0040] Remap the recalculated u(t) to the corresponding compressor frequency f(t);

[0041] The compressor operation is controlled according to the remapped f(t).

[0042] According to a second aspect of the present invention, there is provided an air conditioner, comprising:

[0043] A processor, and a memory connected to the processor;

[0044] The memory is used to store computer programs;

[0045] The processor is used to call and execute the computer program in the memory to perform the above method.

[0046] The technical solution provided by the embodiments of the present invention may have the following beneficial effects:

[0047] After controlling the operation of the compressor according to the PID control method, record the frequency change data of the compressor, and determine whether the compressor enters the steady-state oscillation stage based on the frequency change data. If so, average the compressor frequency in the steady-state oscillation stage to obtain the steady-state frequency fsteady, and adjust the compressor frequency to the steady-state frequency fsteady for operation. This avoids frequent adjustments of the compressor and reduces energy consumption. In addition, due to the use of steady-state oscillation frequency calculation, the accuracy of indoor temperature control is improved and temperature fluctuations are reduced. When approaching the target temperature, the strategy of adjusting the compressor frequency to the steady-state frequency fsteady avoids rapid temperature fluctuations and achieves a rapid and stable temperature response. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 is a flow chart of an air conditioning control method according to an exemplary embodiment;

[0049] Figure 2 is a flowchart of an air conditioning control method according to another exemplary embodiment. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0051] The serial numbers of the following embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0052] In the following embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0053] Embodiment 1

[0054] Figure 1 is a flow chart of an air conditioning control method according to an exemplary embodiment. Figure 1 , the method comprising:

[0055] Step S11, after the unit is started up for the first time, the compressor is controlled to run at the maximum frequency;

[0056] Step S12: When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to a first threshold, the compressor is controlled to operate according to a PID control method;

[0057] Step S13, after controlling the compressor to run according to the PID control method, recording the frequency change data of the compressor;

[0058] Step S14: judging whether the compressor has entered a steady-state oscillation stage according to the frequency change data;

[0059] If yes, average the compressor frequency during the steady-state oscillation phase to obtain the steady-state frequency fsteady;

[0060] Step S15, adjusting the compressor frequency to the steady-state frequency fsteady for operation.

[0061] It should be noted that the technical solution provided in this embodiment is loaded in the controller of the air conditioner in specific practice. The target temperature is the target temperature set by the user, and is obtained by receiving a signal sent by the user through a remote control, or by receiving a signal input by the user through a control panel.

[0062] The existing PID control strategy may still have large frequency fluctuations after reaching the target temperature, resulting in frequent adjustments of the compressor and increased energy consumption. In addition, when the temperature is close to the target temperature, the existing technology is not flexible enough to adjust the compressor frequency, resulting in a slow response speed of the air conditioner and an inability to quickly reach or maintain the target temperature.

[0063] It can be understood that the technical solution provided in this embodiment records the frequency change data of the compressor after controlling the operation of the compressor according to the PID control method, and judges whether the compressor enters the steady-state oscillation stage based on the frequency change data. If so, the compressor frequency in the steady-state oscillation stage is averaged to obtain the steady-state frequency fsteady, and the compressor frequency is adjusted to the steady-state frequency fsteady for operation, thereby avoiding frequent adjustments of the compressor and reducing energy consumption. Moreover, due to the use of steady-state oscillation frequency calculation, the accuracy of indoor temperature control is improved and temperature fluctuations are reduced. When approaching the target temperature, the strategy of adjusting the compressor frequency to the steady-state frequency fsteady avoids rapid temperature fluctuations and achieves a rapid and stable temperature response.

[0064] In specific practice, in step S15, the compressor frequency is adjusted to the steady-state frequency fsteady for operation, specifically:

[0065] When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to a second threshold, the compressor frequency is adjusted to the steady-state frequency fsteady for operation; the second threshold is less than the first threshold.

[0066] In specific practice, the first threshold and the second threshold are set according to user needs, or according to experimental data, or according to historical experience values. For example, the first threshold is set to 2°C and the second threshold is set to 1°C.

[0067] It is understandable that when the unit is just turned on, the compressor is controlled to run at the maximum frequency. Initial startup frequency: set a high frequency (such as 80Hz or 70Hz, and adjust the maximum value according to the model or actual situation) to quickly cool down / heat up. When the indoor temperature is close to the target temperature, that is, when the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to the first threshold, the compressor is controlled to operate according to the PID control method. When the indoor temperature is close to the target temperature, the compressor frequency usually oscillates according to the set logic to maintain a balance between the indoor temperature and the target temperature. Record the frequency change data of the compressor at this time. Analyze the frequency change to determine whether it is in a steady-state oscillation state, and calculate the steady-state frequency based on the frequency of the steady-state vibration segment. By adjusting the compressor frequency to the steady-state frequency fsteady, rapid temperature fluctuations are avoided and a fast and smooth temperature response is achieved.

[0068] In specific practice, the method further includes:

[0069] Calculate the power value of the compressor and the power value of the fan under the steady-state frequency fsteady;

[0070] The sum of the power value of the compressor and the power value of the fan is taken as the steady-state power of the unit;

[0071] The steady-state frequency fsteady and the fan speed corresponding to the steady-state power are stored.

[0072] In specific practice, the method further includes:

[0073] After the unit is restarted, the compressor is controlled to run at the maximum frequency;

[0074] When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to the second threshold, the control unit is directly operated at the compressor frequency and fan speed corresponding to the steady-state power.

[0075] It is understandable that the technical solution provided by this embodiment is that when the machine is turned on next time, the initial cooling / heating stage will still operate normally at high frequency (control the compressor to operate at the maximum frequency), and then when the target temperature is about to be reached (when the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to the second threshold), the compressor frequency and fan speed corresponding to the steady-state power are directly controlled. This control method is simple and easy to operate, and can quickly adjust the indoor temperature to the target temperature, and can ensure low energy consumption at this time. While being efficient and energy-saving, it avoids rapid temperature fluctuations and achieves a fast and stable temperature response. At the same time, the technical solution provided by this embodiment dynamically adjusts the fan speed according to the compressor frequency, optimizes the cooling / heating efficiency, and improves the overall performance of the system.

[0076] In specific practice, the frequency change data of the compressor is recorded in step S13, specifically:

[0077] The compressor frequency data is recorded once per second, and the data format includes:

[0078] Timestamp, current frequency, current temperature, target temperature, error.

[0079] In specific practice, judging whether the compressor enters the steady-state oscillation stage according to the frequency change data in step S14 includes:

[0080] Count the frequency changes of the compressor within a preset time and calculate the standard deviation σ;

[0081] If the standard deviation σ is less than the standard deviation threshold, it is determined that the compressor enters a steady-state oscillation stage.

[0082] In specific practice, the standard deviation threshold is set according to user needs, or according to experimental data, or according to historical experience values. For example, the standard deviation threshold Y is set to 2 Hz.

[0083] In specific practice, the fan speed is calculated according to the following formula (2), including:

[0084] Fan speed N f and compressor frequency f c The linear proportional relationship between: N f = k·f c (2);

[0085] The proportionality coefficient k is adjusted according to specific system performance and design requirements.

[0086] Nf: fan speed (unit: rpm, revolutions per minute)

[0087] fc: compressor frequency (unit: Hz)

[0088] k: proportionality factor (unit: rpm / Hz)

[0089] In practice, the proportionality coefficient k can be determined by experiment or simulation. Experimental determination: Under different compressor frequencies, record the cooling / heating effect of the system to find the best relationship between the fan speed and the compressor frequency. Draw a curve: Draw the recorded data into a graph, analyze the relationship between the fan speed and the compressor frequency, and determine the linear relationship.

[0090] In specific practice, the operation of the compressor is controlled according to the PID control method, including:

[0091] Get the target temperature as T0, the current indoor temperature as T1, and the proportional gain Kp, integral gain Ki, and differential gain Kd set by the user;

[0092] For example, set the proportional gain Kp=2.0; the integral gain Ki=0.1; and the differential gain Kd=0.5.

[0093] Calculation error e(t) = T0-T1;

[0094] Calculate the PID output according to formula (1):

[0095]

[0096] Map the PID output u(t) to the compressor frequency f(t);

[0097] The compressor operation is controlled according to f(t).

[0098] Within the output range (which can be defined by experiments or prior knowledge), the PID output u(t) is mapped to the frequency f(t). A basic mapping formula needs to be defined.

[0099] Linear mapping formula (assuming the reasonable range of PID output is 0 to 100):

[0100]

[0101] When u(t)=0, the compressor frequency f(t)=fmin=30Hz.

[0102] When u(t)=100, the compressor frequency f(t)=fmax=80Hz.

[0103] Preferably, after controlling the operation of the compressor according to the PID control method, the method further comprises:

[0104] Monitor the indoor temperature T1 at preset intervals and recalculate the error e(t) and PID output u(t);

[0105] Remap the recalculated u(t) to the corresponding compressor frequency f(t);

[0106] The compressor operation is controlled according to the remapped f(t).

[0107] In specific practice, the preset interval is set according to user needs, or according to experimental data, or according to historical experience values, for example, set to 1 second.

[0108] It can be understood that the technical solution provided in this embodiment combines PID control with steady-state load calculation to accurately control the compressor frequency, reduce unnecessary energy consumption, and achieve high efficiency and energy saving.

[0109] It should be noted that if the integrated units in the above embodiments are implemented in the form of software functional units and sold or used as independent products, they can be stored in the following computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling one or more computer devices (which may be personal computers, servers or network devices, etc.) to execute all or part of the steps of the methods described in each embodiment of the present application.

[0110] Embodiment 2

[0111] Figure 2 is a flow chart of an air conditioning control method according to another exemplary embodiment. Figure 2 , the method comprising:

[0112] Step S21, after the unit is started up for the first time, control the compressor to run at the maximum frequency;

[0113] Step S22: when the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to a first threshold, the compressor is controlled to operate according to a PID control method;

[0114] Step S23, after controlling the compressor to run according to the PID control method, recording the frequency change data of the compressor;

[0115] Step S24, judging whether the compressor enters a steady-state oscillation stage according to the frequency change data;

[0116] If yes, average the compressor frequency during the steady-state oscillation phase to obtain the steady-state frequency fsteady;

[0117] Step S25, adjusting the compressor frequency to the steady-state frequency fsteady for operation;

[0118] Step S26, calculating the power value of the compressor and the power value of the fan at the steady-state frequency fsteady;

[0119] Step S27, taking the sum of the power value of the compressor and the power value of the fan as the steady-state power of the unit; storing the steady-state frequency fsteady and the fan speed corresponding to the steady-state power;

[0120] Step S28: After the unit is turned on again, the compressor is controlled to run at the maximum frequency;

[0121] Step S29: When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to the second threshold, the control unit is directly operated at the compressor frequency and fan speed corresponding to the steady-state power.

[0122] In specific practice, the first threshold and the second threshold are set according to user needs, or according to experimental data, or according to historical experience values. For example, the first threshold is set to 2°C and the second threshold is set to 1°C.

[0123] For the implementation of the above steps, please refer to Example 1 and will not be repeated here.

[0124] It can be understood that the technical solution provided in this embodiment records the frequency change data of the compressor after controlling the operation of the compressor according to the PID control method, and judges whether the compressor enters the steady-state oscillation stage based on the frequency change data. If so, the compressor frequency in the steady-state oscillation stage is averaged to obtain the steady-state frequency fsteady, and the compressor frequency is adjusted to the steady-state frequency fsteady for operation, thereby avoiding frequent adjustments of the compressor and reducing energy consumption. Moreover, due to the use of steady-state oscillation frequency calculation, the accuracy of indoor temperature control is improved and temperature fluctuations are reduced. When approaching the target temperature, the strategy of adjusting the compressor frequency to the steady-state frequency fsteady avoids rapid temperature fluctuations and achieves a rapid and stable temperature response.

[0125] When the machine is turned on next time, the initial cooling / heating stage will still operate normally at high frequency (control the compressor to run at the maximum frequency), and then when the target temperature is about to be reached (when the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to the second threshold), the compressor frequency and fan speed corresponding to the steady-state power will be directly controlled. This control method is simple and easy to operate, and can quickly adjust the indoor temperature to the target temperature. It can also ensure low energy consumption and high efficiency at this time, while avoiding rapid temperature fluctuations and achieving a fast and smooth temperature response.

[0126] In the several embodiments provided in the present application, it should be understood that the disclosed client can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0127] Embodiment 3

[0128] According to an exemplary embodiment, an air conditioner includes:

[0129] A processor, and a memory connected to the processor;

[0130] The memory is used to store computer programs;

[0131] The processor is used to call and execute the computer program in the memory to perform the above method.

[0132] It can be understood that the technical solution provided in this embodiment records the frequency change data of the compressor after controlling the operation of the compressor according to the PID control method, and judges whether the compressor enters the steady-state oscillation stage based on the frequency change data. If so, the compressor frequency in the steady-state oscillation stage is averaged to obtain the steady-state frequency fsteady, and the compressor frequency is adjusted to the steady-state frequency fsteady for operation, thereby avoiding frequent adjustments of the compressor and reducing energy consumption. Moreover, due to the use of steady-state oscillation frequency calculation, the accuracy of indoor temperature control is improved and temperature fluctuations are reduced. When approaching the target temperature, the strategy of adjusting the compressor frequency to the steady-state frequency fsteady avoids rapid temperature fluctuations and achieves a rapid and stable temperature response.

[0133] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0134] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0135] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. An air conditioning control method, characterized in that: include: After the unit is started up for the first time, the compressor is controlled to run at the maximum frequency; When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to the first threshold, the compressor is controlled to operate according to the PID control method; After the compressor is controlled to run according to the PID control method, the frequency change data of the compressor is recorded; According to the frequency change data, determining whether the compressor has entered a steady-state oscillation stage; If yes, average the compressor frequency during the steady-state oscillation phase to obtain the steady-state frequency fsteady; The compressor frequency is adjusted to the steady-state frequency fsteady for operation.

2. The air conditioning control method according to claim 1, characterized in that: The compressor frequency is adjusted to the steady-state frequency fsteady for operation, specifically: When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to a second threshold, the compressor frequency is adjusted to the steady-state frequency fsteady for operation; the second threshold is less than the first threshold.

3. The air conditioning control method according to claim 2, characterized in that: Also includes: Calculate the power value of the compressor and the power value of the fan under the steady-state frequency fsteady; The sum of the power value of the compressor and the power value of the fan is taken as the steady-state power of the unit; The steady-state frequency fsteady and the fan speed corresponding to the steady-state power are stored.

4. The air conditioning control method according to claim 3, characterized in that: Also includes: After the unit is restarted, the compressor is controlled to run at the maximum frequency; When the absolute value of the difference between the indoor temperature and the target temperature is less than or equal to the second threshold, the control unit is directly operated at the compressor frequency and fan speed corresponding to the steady-state power.

5. The air conditioning control method according to claim 1, characterized in that: The frequency change data of the recorded compressor is specifically: The compressor frequency data is recorded once per second, and the data format includes: Timestamp, current frequency, current temperature, target temperature, error.

6. The air conditioning control method according to claim 1, characterized in that: The step of judging whether the compressor enters a steady-state oscillation stage according to the frequency change data includes: Count the frequency changes of the compressor within a preset time and calculate the standard deviation σ; If the standard deviation σ is less than the standard deviation threshold, it is determined that the compressor enters a steady-state oscillation stage.

7. The air conditioning control method according to claim 3, characterized in that: The fan speed is calculated according to the following formula (2), including: Fan speed N f and compressor frequency f c The linear proportional relationship between: N f = k·f c (2); The proportionality coefficient k is adjusted according to specific system performance and design requirements.

8. The air conditioning control method according to any one of claims 1 to 7, characterized in that: The method of controlling the operation of the compressor according to the PID control method comprises: Get the target temperature as T0, the current indoor temperature as T1, and the proportional gain Kp, integral gain Ki, and differential gain Kd set by the user; Calculation error e(t) = T0-T1; Calculate the PID output according to formula (1): Map the PID output u(t) to the compressor frequency f(t); The compressor operation is controlled according to f(t).

9. The air conditioning control method according to claim 8, characterized in that: After the compressor is controlled to run according to the PID control method, the method further includes: Monitor the indoor temperature T1 at preset intervals and recalculate the error e(t) and PID output u(t); Remap the recalculated u(t) to the corresponding compressor frequency f(t); The compressor operation is controlled according to the remapped f(t).

10. An air conditioner, characterized in that: include: A processor, and a memory connected to the processor; The memory is used to store computer programs; The processor is used to call and execute the computer program in the memory to perform the method according to any one of claims 1 to 9.

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