A control method of an air conditioner and an air conditioner

Abstract

The application provides a control method of an air conditioner and the air conditioner. The control method of the air conditioner comprises the following steps: constructing a room temperature change prediction model according to air conditioner capacity, room temperature change and load; calculating a first temperature change value according to the room temperature change prediction model; controlling the air conditioner to perform a compressor operation frequency reduction operation or a temperature reaching stop operation according to whether the first temperature change value is in a second temperature change range; wherein the first temperature change value is a temperature change value in a temperature reaching stop process and / or a temperature change value in a restart operation process after recovery. The application can reduce cumulative power consumption and achieve the effect of energy saving.

Description

Technical Field

[0001] This invention relates to the field of air conditioner technology, and more specifically, to an air conditioner control method and an air conditioner. Background Technology

[0002] Regarding methods to reduce power consumption of air conditioners under low load, inverter technology is generally used to reduce the frequency of shutdown at temperature and lower the compressor speed. However, with the improvement of residential insulation performance in recent years, the temperature change at temperature shutdown is no longer significant. Because load conditions in the actual environment are constantly changing, it is difficult to determine whether to reduce the frequency to decrease the frequency of shutdown at temperature, or to allow the existence of temperature shutdown to reduce power consumption at a certain moment. Furthermore, given the comfort issues caused by temperature changes during temperature shutdown, it is not advisable to easily increase the frequency of temperature shutdown to reduce power consumption. Summary of the Invention

[0003] To achieve energy-saving control of air conditioners under low load, this invention provides a control method for air conditioners. The control method includes: constructing a room temperature change prediction model based on air conditioning capacity, room temperature changes, and load; calculating a first temperature change value based on the room temperature change prediction model; and controlling the air conditioner to either reduce the compressor operating frequency or perform a temperature-reaching shutdown operation based on whether the first temperature change value falls within a second temperature change range; wherein the first temperature change value is the temperature change value during the temperature-reaching shutdown process and / or the temperature change value during the restart process after recovery.

[0004] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: By constructing a room temperature change prediction model based on air conditioning capacity, room temperature changes, and load, temperature changes can be predicted based on the room temperature change prediction model. This allows for adjustment of the frequency of temperature-reaching shutdown based on constantly changing load conditions, ensuring that temperature changes are within the allowable range and power consumption is reduced. When the predicted temperature change exceeds the allowable range, the system switches to a mode that prohibits entering the temperature-reaching shutdown operation, thereby reducing cumulative power consumption and achieving energy-saving effects.

[0005] In one embodiment of the present invention, controlling the air conditioner to reduce the compressor operating frequency or to stop the operation when the first temperature change value is within the second temperature change range includes: if the first temperature change value is not within the second temperature change range, controlling the air conditioner to reduce the compressor operating frequency; if the first temperature change value is within the second temperature change range, controlling the air conditioner to reduce the compressor operating frequency or to stop the operation when the temperature is reached based on the cumulative power consumption; the upper limit of the second temperature change range is the temperature threshold for stopping the operation when the temperature is reached, and the lower limit of the second temperature change range is the recovery temperature.

[0006] Compared with existing technologies, the technical effects achieved by this solution are as follows: If the first temperature change value is not within the second temperature change range, it indicates that the temperature change value during the temperature-reaching shutdown process or the restart control process after recovery exceeds the upper and lower temperature limits and cannot be suppressed by control. Therefore, the existing control method is selected to control the air conditioner to reduce the compressor operating frequency to the necessary minimum value. If the first temperature change value is within the second temperature change range, the cumulative power consumption is calculated using the CC (compressor characteristic curve) method to reduce the frequency to the necessary minimum value and the temperature-reaching shutdown method. Based on the cumulative power consumption, the air conditioner is controlled to reduce the compressor operating frequency or perform a temperature-reaching shutdown operation to reduce the cumulative power consumption and achieve energy-saving control of the air conditioner.

[0007] In one embodiment of the present invention, controlling the air conditioner to perform a reduction in compressor operating frequency or a temperature-reaching shutdown operation based on cumulative power consumption includes: calculating a first cumulative power consumption for controlling the air conditioner to perform a reduction in compressor operating frequency and a second cumulative power consumption for controlling the air conditioner to perform a temperature-reaching shutdown operation using the compressor characteristic curve method; if the second cumulative power consumption is greater than or equal to the first cumulative power consumption, then controlling the air conditioner to perform a reduction in compressor operating frequency; if the second cumulative power consumption is less than the first cumulative power consumption, then controlling the air conditioner to perform a temperature-reaching shutdown operation.

[0008] Compared with existing technologies, the technical effects achieved by this solution are as follows: If the second cumulative power consumption is greater than or equal to the first cumulative power consumption, it indicates that the cumulative power consumption is higher when using the temperature-reaching shutdown method, thus controlling the air conditioner to reduce the compressor operating frequency. If the second cumulative power consumption is less than the first cumulative power consumption, it indicates that the cumulative power consumption is higher when using the method of reducing the frequency to the necessary minimum value, thus controlling the air conditioner to perform the temperature-reaching shutdown operation.

[0009] In one embodiment of the present invention, the control method of the air conditioner further includes: if the air conditioner is controlled to perform a temperature-reaching shutdown operation, then the lower limit of the compressor operating frequency is increased.

[0010] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: by increasing the lower limit of the compressor's operating frequency, the difficulty of the air conditioner reaching the temperature and shutting off can be reduced, making it easier for the air conditioner to enter the temperature-reaching and shutting-off state.

[0011] In one embodiment of the present invention, the step of constructing a room temperature change prediction model based on air conditioning capacity, room temperature change, and load includes: obtaining a fitting curve of the air conditioning capacity and the room temperature change under a certain load.

[0012] Compared to existing technologies, the technical effects achieved by this solution are as follows: According to the formula for room temperature change = (air conditioning capacity – load) / {(specific heat of air × air mass)}, under a constant load, room temperature change is proportional to air conditioning capacity. Energy released and stored by walls and windows are considered included in the load. Air conditioning capacity can be estimated using the compressor characteristic curve method, meaning it can be estimated using compressor frequency and temperature information; while temperature change can be measured using the indoor unit's intake air temperature sensor. In other words, a correlation curve between air conditioning capacity and the rate of room temperature change can be fitted using three or more data points with different air conditioning capacity (compressor frequency).

[0013] In one embodiment of the present invention, the load must include: the outdoor temperature change value is less than the outdoor temperature change threshold.

[0014] In one embodiment of the present invention, the load must also include: the brightness change value is less than the brightness change threshold.

[0015] In one embodiment of the present invention, the load must also include: no change in the number of people indoors.

[0016] This invention provides an air conditioner that implements any of the control methods described above. The air conditioner includes: a construction module for constructing a room temperature change prediction model based on air conditioning capacity, room temperature change, and load; a calculation module for calculating a first temperature change value based on the room temperature change prediction model; and a control module for controlling the air conditioner to perform a reduction in compressor operating frequency or a temperature-reaching shutdown operation based on whether the first temperature change value is within a second temperature change range. The first temperature change value is the temperature change value during the temperature-reaching shutdown process and / or the temperature change value during the restart process after recovery.

[0017] This invention provides an air conditioner, which includes a controller for executing an executable program to implement any of the control methods for an air conditioner as described above.

[0018] By adopting the technical solution of the present invention, the following technical effects can be achieved: (1) By constructing a room temperature change prediction model based on air conditioning capacity, room temperature change and load, temperature change can be predicted based on the room temperature change prediction model. This allows for adjustment of the frequency of temperature-reaching shutdown for load conditions that change over time, ensuring that temperature changes are within the allowable range and power consumption is reduced. When the predicted temperature change exceeds the allowable range, the system switches to a mode that prohibits entering the temperature-reaching shutdown operation, thereby reducing cumulative power consumption and achieving energy saving.

[0019] (2) If the first temperature change value is not within the second temperature change range, it indicates that the temperature change value during the temperature-reaching shutdown process or the restart control process after recovery exceeds the upper and lower temperature limits and cannot be suppressed by control. Therefore, the existing control method is selected to control the air conditioner to perform the operation of reducing the compressor operating frequency and reducing the compressor frequency to the necessary minimum value. If the first temperature change value is within the second temperature change range, the cumulative power consumption is calculated by using the CC (compressor characteristic curve) method to reduce the frequency to the necessary minimum value and the temperature-reaching shutdown method. Based on the cumulative power consumption, the air conditioner is controlled to perform the operation of reducing the compressor operating frequency or the operation of reaching the temperature to reduce the cumulative power consumption and achieve energy-saving control of the air conditioner.

[0020] (3) According to the formula for room temperature change = (air conditioning capacity – load) / {(specific heat of air × air mass)}, under a constant load, the room temperature change is proportional to the air conditioning capacity. The air conditioning capacity can be estimated using the compressor characteristic curve method, that is, the air conditioning capacity can be estimated using the compressor frequency and temperature information; while the temperature change can be measured using the indoor unit's air intake temperature sensor. In other words, the correlation curve between the air conditioning capacity and the rate of change of room temperature can be fitted using more than three data points with different air conditioning capacities (compressor frequencies). Attached Figure Description

[0021] Figure 1 This is a flowchart illustrating a control method for an air conditioner provided by the present invention.

[0022] Figure 2 for Figure 1 A schematic diagram illustrating the specific control method of a central air conditioner.

[0023] Figure 3 This is a fitted curve of air conditioning capacity versus the rate of change of room temperature when the load is constant.

[0024] Figure 4 This is a schematic diagram showing the temperature change when the unit stops operating at the set temperature during refrigeration.

[0025] Figure 5 This diagram illustrates the temperature and power consumption changes when the system enters the shutdown control phase at the set temperature.

[0026] Figure 6 This is a schematic diagram of an air conditioner module provided by the present invention. Detailed Implementation

[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0028] See Figure 1This is a flowchart illustrating a control method for an air conditioner provided by the present invention. Combined with... Figures 1 to 5 The control method for the air conditioner includes, for example, the following steps: S10: constructing a room temperature change prediction model based on the air conditioning capacity, room temperature change, and load; S20: calculating a first temperature change value based on the room temperature change prediction model; S30: controlling the air conditioner to reduce the compressor operating frequency or perform a temperature-reaching shutdown operation based on whether the first temperature change value is within a second temperature change range; wherein, the first temperature change value is the temperature change value during the temperature-reaching shutdown process and / or the temperature change value during the restart process after recovery.

[0029] Understandably, by constructing a room temperature change prediction model based on air conditioning capacity, room temperature changes, and load, temperature changes can be predicted. This allows for adjustments to the frequency of temperature-reaching shutdown based on constantly changing load conditions, ensuring that temperature changes remain within acceptable limits and power consumption is reduced. When the predicted temperature change exceeds the acceptable range, the system switches to a mode that prohibits entering the temperature-reaching shutdown operation, thereby reducing cumulative power consumption and achieving energy-saving effects.

[0030] Furthermore, the step of controlling the air conditioner to reduce the compressor operating frequency or to stop the air conditioner when the first temperature change value is within the second temperature change range includes: if the first temperature change value is not within the second temperature change range, controlling the air conditioner to reduce the compressor operating frequency; if the first temperature change value is within the second temperature change range, controlling the air conditioner to reduce the compressor operating frequency or to stop the air conditioner when the temperature is reached based on the cumulative power consumption; the upper limit of the second temperature change range is the temperature threshold for stopping the air conditioner when the temperature is reached, and the lower limit of the second temperature change range is the recovery temperature.

[0031] Understandably, if the first temperature change value is not within the second temperature change range, it indicates that the temperature change value during the temperature-reaching shutdown process or the restart control process after recovery exceeds the upper and lower temperature limits and cannot be suppressed by control. Therefore, the existing control method is selected to control the air conditioner to reduce the compressor operating frequency to the necessary minimum value. If the first temperature change value is within the second temperature change range, the cumulative power consumption is calculated using the CC (compressor characteristic curve) method to reduce the frequency to the necessary minimum value and the temperature-reaching shutdown method. Based on the cumulative power consumption, the air conditioner is controlled to reduce the compressor operating frequency or perform a temperature-reaching shutdown operation to reduce the cumulative power consumption and achieve energy-saving control of the air conditioner.

[0032] Furthermore, the step of controlling the air conditioner to reduce the compressor operating frequency or to stop the air conditioner when it reaches the set temperature based on the cumulative power consumption includes: calculating the first cumulative power consumption for controlling the air conditioner to reduce the compressor operating frequency and the second cumulative power consumption for controlling the air conditioner to stop the air conditioner when it reaches the set temperature using the compressor characteristic curve method; if the second cumulative power consumption is greater than or equal to the first cumulative power consumption, then the air conditioner is controlled to reduce the compressor operating frequency; if the second cumulative power consumption is less than the first cumulative power consumption, then the air conditioner is controlled to stop the air conditioner when it reaches the set temperature.

[0033] Understandably, if the second cumulative power consumption is greater than or equal to the first cumulative power consumption, it indicates that the cumulative power consumption is higher when using the temperature-reaching shutdown method, thus the air conditioner is controlled to reduce the compressor operating frequency. If the second cumulative power consumption is less than the first cumulative power consumption, it indicates that the cumulative power consumption is higher when using the method of reducing the frequency to the necessary minimum value, thus the air conditioner is controlled to perform the temperature-reaching shutdown operation.

[0034] Furthermore, the control method for the air conditioner also includes: if the air conditioner is controlled to perform a temperature-reaching shutdown operation, then the lower limit of the compressor operating frequency is increased.

[0035] It is understandable that by increasing the lower limit of the compressor's operating frequency, the difficulty of the air conditioner reaching the temperature and then shutting off can be reduced, making it easier for the air conditioner to enter the temperature-reaching and shut-off state.

[0036] Furthermore, the step of constructing a room temperature change prediction model based on air conditioning capacity, room temperature change, and load includes: obtaining a fitting curve of the air conditioning capacity and the room temperature change under a certain load.

[0037] It is understandable that, according to the formula for room temperature change = (air conditioning capacity – load) / {(specific heat of air × air mass)}, under a constant load, room temperature change is proportional to air conditioning capacity. Energy released and stored by walls, windows, etc., is considered included in the load. Air conditioning capacity can be estimated using the compressor characteristic curve method; that is, air conditioning capacity can be estimated using compressor frequency and temperature information. Temperature change can be measured using the indoor unit's intake air temperature sensor. In other words, a correlation curve between air conditioning capacity and the rate of room temperature change can be fitted using three or more data points with different air conditioning capacity (compressor frequency).

[0038] Furthermore, the load must include: an outdoor temperature change value less than an outdoor temperature change threshold. The outdoor temperature change value can be obtained from an outdoor temperature sensor; the preferred value for this outdoor temperature change threshold is 1°C.

[0039] Furthermore, the load must also include: the brightness change value is less than the brightness change threshold. The brightness change value can be obtained from a brightness sensor; the preferred value for this brightness change value is 2000 lx.

[0040] Furthermore, the load must also include: no change in the number of people indoors. The change in the number of people indoors can be obtained using human body detection sensors.

[0041] In one specific embodiment, the room temperature change prediction model fits a formula based on the air conditioning capacity and temperature change data over a certain period. The relevant data should be acquired under a certain load, and the determination of a certain load is based on the outdoor temperature change value. The determination of a certain load includes four modes, and the mode used is determined based on the actual sensors used in the product. (A) Outdoor temperature sensor change within 1°C; (B) Brightness sensor change within 2000 lx; ​​(C) No change in the number of people indoors as determined by human body detection. The four modes include: 1. Only (A) is true; 2. Both (A) and (B) are true; 3. Both (A) and (C) are true; 4. (A), (B), and (C) are true.

[0042] When the load is constant, the fitting curve of air conditioning capacity versus the rate of change of room temperature is as follows: Figure 3 As shown. Its intersection with the vertical axis represents the rate of temperature change when the air conditioner is not running, i.e., when the air conditioning capacity is 0, i.e., the rate of temperature change under load. Its intersection with the horizontal axis represents the load value W. The rate of temperature change is negative when the air conditioner is running in cooling mode and positive when it is stopped.

[0043] Considering the slow response to room temperature changes, the room temperature change rate is taken as the last minute after the air conditioning capacity is changed and maintained for 5 minutes.

[0044] For example, combining Figure 4 When the temperature threshold for stopping the refrigeration operation is set as the lower limit and the recovery temperature is set as the upper limit, the temperature changes at the temperature stop and recovery times can be calculated based on the room temperature change prediction model.

[0045] When a significant temperature change is predicted, the air conditioner is controlled to reduce the compressor's operating frequency to the necessary minimum. This is determined by the room temperature change prediction model, which determines that the time from when the unit stops operating at the predicted temperature to when it resumes operation, plus one minute, does not exceed the upper temperature limit. It should be noted that, considering the slow response to room temperature changes, the temperature rise may continue after the unit stops operating at the predicted temperature and resumes operation; therefore, a one-minute margin is provided.

[0046] For example, when the target temperature is 24℃, the lower limit is 22.5℃, and the upper limit is 25.5℃, the temperature change rate under load, obtained from the fitted curve of air conditioning capacity and room temperature change rate, is 0.41℃ / min, and the restart standby time is 5 minutes. After 5+1 minutes under load only, the lower limit of 22.5℃ (Ts) is 22.5 + 0.41 * 6 = 24.96℃ < 25.5℃, meaning it does not exceed the upper limit, and is added to the temperature shutdown adjustment.

[0047] Considering the scenario from temperature shutdown to recovery, the lower limit frequency will be the maximum value of the frequencies at which the compressor starts operating from the upper temperature limit and during normal operation does not fall below the lower temperature limit. If the frequency falls below the lower temperature limit during startup, the lower limit frequency will be the lowest operating frequency of the compressor.

[0048] For example, when the target temperature is 24℃, the lower limit is 22.5℃, and the upper limit is 25.5℃, the compressor frequency is set to 35Hz and the minimum running time to 3 minutes when restarting control. When the compressor frequency is 35Hz, according to the CC (compressor characteristic curve) method, the corresponding air conditioning capacity is 2153W. Based on the fitted curve and using the room temperature prediction model, the room temperature change rate is -0.69℃ / min. The temperature Tg after 3+1 minutes of restarting control from the upper limit of 25.5℃ is Tg = 25.5 - 0.69 * 4 = 22.74℃. Typically, with a minimum running time of 1 minute and a margin of 1 minute, the total room temperature change rate for 2 minutes (not lower than the lower limit) is -0.24℃ / 2min = -0.12℃ / min. Using the room temperature prediction model, the air conditioning capacity is 1057W. At this time, the compressor frequency is 17Hz.

[0049] The relationship between air conditioning capacity and compressor frequency obtained from the CC method is shown in the table below: Compression frequency / Hz 13 14 15 16 17 18 19 20 Air conditioning capacity / W 815 876 936 996 1057 1117 1178 1238 For example, when using the existing control and setting the frequency to the necessary minimum, according to the room temperature prediction model, the air conditioning capacity and the air conditioning capacity under load balance are 815W. At this time, the compressor frequency, as shown in the table above, is 13Hz. The power consumption, calculated using the CC method, is 202W, and the cumulative power consumption per hour is 202Wh. When using the temperature-reaching shutdown control, the cumulative power consumption per hour is calculated to be 184Wh. Based on the above results, when the target temperature is 24℃, the lower limit is 22.5℃, and the upper limit is 25.5℃, selecting the temperature-reaching shutdown control results in lower power consumption.

[0050] Furthermore, this invention provides an air conditioner. (In conjunction with...) Figure 6The air conditioner 200 includes, for example, a construction module 210, a calculation module 220, and a control module 230. The construction module 210 is used to construct a room temperature change prediction model based on air conditioning capacity, room temperature changes, and load. The calculation module 220 is used to calculate a first temperature change value based on the room temperature change prediction model. The control module 230 is used to control the air conditioner to either reduce the compressor operating frequency or perform a temperature-reaching shutdown operation based on whether the first temperature change value is within a second temperature change range. The first temperature change value is the temperature change value during the temperature-reaching shutdown process and / or the temperature change value during the restart process after recovery.

[0051] In one specific embodiment, the construction module 210, the calculation module 220, and the control module 230 cooperate with each other to implement any of the control methods for an air conditioner as described above, and can achieve the same effect. To avoid repetition, they will not be described again here.

[0052] Furthermore, the present invention provides an air conditioner, the air conditioner including a controller, the controller being used to execute an executable program to implement any of the control methods of the air conditioner described above, and to achieve the same effect, which will not be repeated here to avoid repetition.

[0053] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A control method for an air conditioner, characterized in that, The control method for the air conditioner includes: A room temperature change prediction model is constructed based on air conditioning capacity, room temperature changes, and load. The first temperature change value is calculated based on the room temperature change prediction model. Based on whether the first temperature change value is within the second temperature change range, the air conditioner is controlled to either reduce the compressor operating frequency or perform a temperature-reaching shutdown operation. The first temperature change value is the temperature change value during the temperature-reaching shutdown process and / or the temperature change value during the recovery and restart process; The step of controlling the air conditioner to reduce the compressor operating frequency or to stop the air conditioner when the temperature is reached, based on whether the first temperature change value is within the second temperature change range, includes: If the first temperature change value is not within the range of the second temperature change, then the air conditioner is controlled to reduce the compressor operating frequency. If the first temperature change value is within the range of the second temperature change, the air conditioner is controlled to either reduce the compressor operating frequency or stop the machine when the temperature is reached, based on the cumulative power consumption. The upper limit of the second temperature range is the temperature threshold for stopping the machine when the temperature reaches its maximum, and the lower limit of the second temperature range is the recovery temperature. The method of controlling the air conditioner to reduce the compressor operating frequency or to stop the air conditioner when the temperature is reached based on the cumulative power consumption includes: The first cumulative power consumption for controlling the air conditioner to reduce the compressor operating frequency and the second cumulative power consumption for controlling the air conditioner to achieve temperature-reaching shutdown are calculated using the compressor characteristic curve method. If the second cumulative power consumption is greater than or equal to the first cumulative power consumption, then the air conditioner is controlled to reduce the compressor operating frequency. If the second cumulative power consumption is less than the first cumulative power consumption, then control the air conditioner to perform a temperature-reaching shutdown operation; The control method for the air conditioner also includes: If the air conditioner is to be controlled to perform a temperature-reaching shutdown operation, then the lower limit of the compressor operating frequency should be increased. The method for constructing a room temperature change prediction model based on air conditioning capacity, room temperature changes, and load includes: Under a constant load, obtain the fitting curve of the air conditioning capacity versus the change in room temperature; Wherein, room temperature change = (air conditioning capacity – load) / {(specific heat of air × air mass)}; The lower limit of the temperature is 22.5℃, and the upper limit of the temperature is 25.5℃.

2. The control method for an air conditioner according to claim 1, characterized in that, The load must include: the outdoor temperature change value is less than the outdoor temperature change threshold.

3. The control method for an air conditioner according to claim 2, characterized in that, The load must also include: the brightness change value is less than the brightness change threshold.

4. The control method for an air conditioner according to claim 2, characterized in that, The load must also include: no change in the number of people indoors.

5. An air conditioner, characterized in that, The air conditioner implements the control method of the air conditioner as described in any one of claims 1-4, and the air conditioner includes: The module is used to build a predictive model for room temperature changes based on air conditioning capacity, room temperature changes, and load. The calculation module is used to calculate the first temperature change value based on the room temperature change prediction model; The control module is used to control the air conditioner to reduce the compressor operating frequency or to stop the air conditioner when the temperature is reached, depending on whether the first temperature change value is within the second temperature change range. Wherein, the first temperature change value is the temperature change value during the temperature-reaching shutdown process and / or the temperature change value during the recovery and restart process.

6. An air conditioner, characterized in that, The air conditioner includes a controller for executing an executable program to implement the control method of the air conditioner according to any one of claims 1-4.

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