A constant air volume control method, storage device and air conditioner

Abstract

The application provides a constant air volume control method, a storage device and an air conditioner, and comprises the following steps: S1: determining in advance a constant air volume C i obtained under static pressure P i , corresponding motor current y and motor speed x, fitting to obtain a linear relationship between the motor current y and the motor speed x when the constant air volume is C i : y=a i *x+b i， , wherein i=1, 2, 3,..., n; S3: increasing the motor speed by △X every time interval, and recording the current motor current Y k、 , the motor speed X k， , until the maximum speed X max is reached; S4: performing linear fitting on the recorded speed X k， and current Y k , and obtaining a relationship between the motor current y and the motor speed x: y=c*x+d; S5: calculating i intersection points (Xi, Yi) of y=c*x+d and y=a i *x+b i ; according to the characteristics that the motor speed and the motor current are linearly related, and the linear coefficients are different under different working conditions, the constant air volume control is realized by calculating the intersection points of the two fitted straight lines, without changing the structure of the air conditioner or adding additional components, and the cost is saved.

Description

Technical Field

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

[0002] Currently, air conditioner settings are controlled in two ways: speed control and airflow control. Speed ​​control means that the airflow speed is fixed for each setting, while airflow control means that the airflow is fixed for each setting. The former has a simpler control logic, but because different users have different usage environments, the airflow of the air conditioner at the same speed will be different. The amount of airflow directly affects the user's comfort when using the air conditioner, so airflow control technology has a very significant effect on improving user comfort.

[0003] Currently, the main method for controlling air volume is to install a static pressure sensor inside the air conditioner and adjust the fan speed based on the collected real-time static pressure data, thereby achieving a constant air volume. However, this method requires additional installation space and increases costs. Summary of the Invention

[0004] The problem solved by this invention is that existing air conditioners require the installation of a static pressure sensor to adjust the fan speed based on the detected static pressure data, thereby achieving a constant airflow. However, this requires additional space for the static pressure sensor installation and increases costs.

[0005] To solve the above problems, the present invention provides a constant air volume control method, comprising the following steps: S1: pre-determining the static pressure P i Obtain a constant air volume C i When the corresponding motor current y and motor speed x are fitted, the result is obtained at a constant airflow of C. i At that time, the linear relationship between the motor current y and the motor speed x for n groups under different static pressures is: y = a i x+b i， Where i = 1, 2, 3...n; and the fitting coefficient a i b i S2: The air conditioner is run. If the conditions for executing the constant air volume regulation program are met, proceed to S3. Otherwise, when the user sets the fan speed, the default motor speed is selected from the program. S3: The initial motor speed X0 is set. After a certain period of time, the motor speed ΔX is increased, and the current motor current Y is recorded. k、 Motor speed X k， Until the maximum speed X is reached max， Where k = 0, 1, 2, 3…n; when k > 1, X k =X k-1 +△X; S4: Record the rotational speed Xk， Current Y k By performing linear fitting, the relationship between motor current y and motor speed x is obtained as y=c x+d; S5: The controller calculates y=c x+d and y=a i x+b i The i intersection points are obtained (X) i ,Y i S6: When the user sets the wind speed, the corresponding motor speed calculated in step S5 will be used for operation.

[0006] Compared with existing technologies, the technical advantages achieved by this solution are: before factory setup, the static pressure P at multiple different pressures is pre-measured. i Obtain a constant air volume C i At that time, multiple sets of motor currents and motor speeds were fitted into a linear relationship, and the fitting coefficient α was used to... i b i The data is stored in a device with a storage function; then, when the air conditioner enters the constant air volume regulation program execution condition, the rotational speed X is obtained. k， Current Y k Linear fitting is performed to obtain the relationship between motor current y and motor speed x. Then, the controller calculates and obtains i intersection points (X). i ,Y i This allows users to set the fan speed and obtain the corresponding motor speed. The linear coefficient varies under different operating conditions. Constant air volume control is achieved by calculating the intersection of two fitted straight lines. This eliminates the need to change the air conditioner structure or add extra components (static pressure sensor), thus saving costs.

[0007] In this embodiment, in step S1, the air conditioner is pre-measured to obtain a constant air volume C under multiple different static pressures before being set at the factory. i At that time, the fitting coefficient a i b i Stored in a device with storage functionality.

[0008] The technical effect of adopting this solution is that, before factory settings, a constant air volume C is obtained under multiple different static pressures. i At that time, multiple sets of motor currents and motor speeds were fitted into a linear relationship, and the fitting coefficient α was used to... i b i Stored in a device with storage capabilities for subsequent linear fitting.

[0009] In this embodiment, the different static pressure values ​​include P1, P2, P3...P n The difference between two adjacent static pressure values ​​is ΔP, where ΔP = P.n -P n-1 The ΔP is a constant.

[0010] The technical effect of adopting this solution is that, in order to ensure that the static pressure values ​​are set at different levels before factory settings and that the static pressure values ​​are set at equal intervals, ΔP=P n -P n-1 This means ensuring that the difference between the static pressure values ​​on both sides remains the same, so that the obtained linear relationship is more phased.

[0011] In this embodiment, the execution conditions for the constant air volume adjustment program include one or more of the following: timed entry, remote control entry, and entry during the first run after the air conditioner is turned on.

[0012] The technical effect of adopting this technical solution is that there are many ways to set the execution conditions of the constant air volume adjustment program. Specifically, it can be entered by timed entry, remote control entry, or entry during the first run after the air conditioner is turned on. The diverse options can meet different user needs, or the corresponding entry method can be set according to the different environments in which the air conditioner is located.

[0013] In this embodiment, increasing the motor speed ΔX at regular intervals includes according to X k-1 After running at a speed of t seconds, according to X k The rotational speed operates for t seconds, and X k =X k-1 +△X.

[0014] The technical effect of adopting this solution is that the motor current and motor speed can be detected within a time period of t seconds, so that the detected data is more accurate.

[0015] In this embodiment, the corresponding parameter X varies depending on the environment in which the air conditioner is located. max X0, △X, and t can all be set accordingly.

[0016] The technical effect of adopting this solution is that, since the environment in which the air conditioner is located varies, such as in a regular room, a factory, or a rented house, the corresponding parameters can be changed and set according to the on-site environment.

[0017] In this embodiment, the default motor speed in the program described in step S2 is one of 600, 750, 800, 900, 1000, 1050, and 1200 rpm.

[0018] The technical effect of adopting this technical solution is that the default motor speed can be selected from the above speeds. When the execution conditions of the constant air volume adjustment program are not met, the system selects the speed corresponding to the user's air volume level.

[0019] In this embodiment, the air conditioner has a constant air volume mode and multiple fan speeds in the constant air volume mode, each fan speed corresponding to a constant air volume.

[0020] The technical effect of adopting this solution is that the air conditioner can achieve a constant air volume, and there are multiple fan speeds in the constant air volume mode, which can be switched to switch between different constant air volumes.

[0021] In this embodiment, a storage device executing the constant airflow control method includes: a storage module for storing the fitting coefficients a from step S1. i b i The rotational speed X used to store the rotational speed in step S4 k， Current Y k and the i intersection points stored in step S5; a calculation module for fitting y=a in step S1. i x+b i Fitting y=c in step S4 x+d and the calculation of y=c in step S5. x+d and y=a i x+b i The i intersection points.

[0022] The technical effect of adopting this solution is that the storage module is used to store data, and the calculation module is used to fit the relationship and the intersection of the two sets of relationships, which are then recorded in the stored data. In this way, when the user sets the wind speed, the intersection data in the storage module can easily tell how much speed needs to be output.

[0023] In this embodiment, an air conditioner includes the constant air volume control method described above.

[0024] The technical effect of adopting this technical solution is that it can achieve the above-mentioned technical effects, which will not be elaborated here. Attached Figure Description

[0025] Figure 1 This is a graph showing the linear relationship between motor speed and motor current under the condition of constant static pressure (static pressure of P1) and variable air volume in this invention. Figure 2 This is a linear relationship diagram of motor speed and motor current under the condition of constant static pressure (static pressure P1, P2, P3) and variable air volume in this invention. Figure 3 A schematic diagram showing the point at which the constant air volume speed and current are determined by the intersection of two lines in this invention; Figure 4This is a schematic diagram of the rotational speed under different air volumes and static pressures in this invention; Figure 5 This is a schematic diagram of the rotational speed and current under constant air volume and variable static pressure conditions in this invention. Figure 6 These are the coefficients for linear fitting under different constant air volumes in this invention. Detailed Implementation

[0026] In fluid mechanics, static pressure is used to represent the degree to which a pipe hinders the flow of fluid. Static pressure is an inherent property of the pipe itself and is independent of the fluid velocity inside the pipe. It is related to the length, surface roughness, curvature, and cross-sectional area of ​​the pipe.

[0027] In an air conditioner, the air volume is related to the cross-sectional area of ​​the air outlet and the air velocity at the outlet. The cross-sectional area of ​​the air outlet is usually constant, while the air velocity at the outlet is affected by the fan speed and static pressure. When the static pressure is constant, the higher the fan speed, the higher the air velocity at the outlet, and the greater the air volume. When the fan speed is constant, the higher the static pressure, the lower the air velocity at the outlet, and the smaller the air volume.

[0028] To address the aforementioned technical problems, this invention employs the following concept: the fan speed and its Q-axis current have a linear relationship, and this linear expression varies under different operating conditions, primarily influenced by static pressure and airflow. When both static pressure and airflow are fixed, the required fan speed and corresponding current are determined. When static pressure is fixed and airflow is variable, a series of speed and current data can be obtained by changing the airflow conditions (static pressure is constant; changing the airflow requires changing the speed). Then, an expression for the speed and current is fitted. Different static pressure values ​​result in different fitted expressions. When airflow is fixed and static pressure is variable, a series of speed and current data can be obtained by changing the static pressure conditions (to ensure constant airflow, changing the static pressure requires changing the fan speed to maintain a constant output airflow). Then, an expression for the speed and current is fitted. Different airflow values ​​result in different fitted expressions.

[0029] Based on the above principle, the relationship between the rotational speed and current under constant airflow and variable static pressure can be pre-tested when the airflow is C (C is known and determined according to specific requirements). Then, during actual operation of the air conditioner, the relationship between the rotational speed and current under constant static pressure and variable airflow can be calculated using multiple sets of rotational speed and current values. Finally, the intersection of the two straight lines is calculated to obtain the rotational speed required for the output airflow of C under the current static pressure conditions. This allows for the achievement of a constant airflow without using a static pressure sensor.

[0030] 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.

[0031] This invention provides a constant air volume control method, comprising the following steps: S1: Pre-determining the static pressure P i Obtain a constant air volume C i When the motor current y and motor speed x are fitted together, the result is obtained at a constant airflow of C. i At that time, the linear relationship between the motor current y and the motor speed x for n groups under different static pressures is: y = a i x+b i， Where i = 1, 2, 3...n; and the fitting coefficient a i b i S2: The air conditioner is run. If the conditions for executing the constant air volume regulation program are met, proceed to S3. Otherwise, when the user sets the fan speed, the default motor speed is selected from the program. S3: The initial motor speed X0 is set. After a certain period of time, the motor speed ΔX is increased, and the current motor current Y is recorded. k、 Motor speed X k， Until the maximum speed X is reached max， Where k = 0, 1, 2, 3…n; when k > 1, X k= X k-1 +△X; S4: Record the rotational speed X k， Current Y k By performing linear fitting, the relationship between motor current y and motor speed x is obtained as y=c x+d; S5: The controller calculates y=c x+d and y=a i x+b i The i intersection points are obtained (X) i ,Y i S6: When the user sets the wind speed, the corresponding motor speed calculated in step S5 will be used for operation.

[0032] Before being set at the factory, a constant air volume C was obtained by measuring in the laboratory under multiple different static pressures. i At that time, the corresponding multiple sets of motor currents and motor speeds, due to the achievement of a constant air volume C under different static pressures. i At this time, the motor speed needs to change accordingly, and the motor current also needs to change, so as to obtain a linear relationship between the motor current y and the motor speed x: y=a i x+b i And the fitting coefficient a i b i The data is stored in a storage device for fitting and calculation with subsequent detection data. This storage device can be an EEPROM data chip. For example... Figure 1The graph shows the linear relationship between motor speed and motor current under constant static pressure (static pressure P1) and variable air volume conditions; as shown. Figure 2 The graph shows the linear relationship between motor speed and motor current under the condition of constant static pressure (static pressure values ​​P1, P2, P3) and variable air volume. Figure 6 The coefficients a of the linear fitting under different constant air volumes were obtained. i b i And for reference Figure 5 The table shows the relationship between rotational speed and current under constant air volume and static pressure conditions.

[0033] After purchasing the air conditioner, the user installs it in the desired location. Then, when the user uses the air conditioner, the system checks if the constant airflow regulation program's execution conditions are met. If not, the system directly selects the motor speed from the default settings when the user sets the fan speed. For example, if the user sets the fan speed to level 1, the motor speed will be set to 600 rpm. The relationship between static pressure and airflow using the default program can be referenced. Figure 4 .

[0034] When the conditions for executing the constant air volume regulation program are met, the air conditioner enters a detection period, gradually increasing the motor speed and recording the motor current Y at each speed. k、 Motor speed X k， Until the maximum speed X is reached max This will record the motor current Y. k、 Motor speed X k By performing linear fitting, the relationship between motor current y and motor speed x under the current air conditioning environment is obtained as y=c x+d, then compared with y=a pre-stored in the EEPROM data chip. i x+b i Perform an intersection point operation to obtain n intersection points, resulting in (X) i ,Y i This way, when the user sets the wind speed, it can be done through the intersection (X). i ,Y i The corresponding motor speed is obtained directly, and the motor only needs to output the calculated motor speed to achieve constant air volume output of the air conditioner under this environment.

[0035] like Figure 3 The point where the constant air volume speed and current are determined by the intersection of the two lines is described above.

[0036] The purpose of the above-mentioned method is to eliminate the need for additional components. Compared to the prior art which requires the installation of a static pressure sensor, this application does not need to know the specific amount of static pressure in this environment to achieve constant airflow and motor speed in this environment.

[0037] Since air conditioners are rarely disassembled after installation, and the environment changes little, there is no need to check whether the constant air volume adjustment program is met each time. However, if the air conditioner is installed in an environment with frequent changes, such as a factory environment with a lot of dust and smoke, then it is necessary to check whether the constant air volume adjustment program is met each time.

[0038] Among them, the execution conditions of the constant air volume regulation program are met under the constant static pressure and variable air volume conditions. The system will automatically determine whether the constant static pressure and variable air volume conditions can be met.

[0039] In step S1, the static pressure P of the air conditioner is pre-measured before it is factory-set. i Obtain a constant air volume C i At that time, the corresponding motor current y and motor speed x are used, and the fitting coefficient a is used to determine the relationship between them. i b i Stored in a device with storage functionality.

[0040] As described above, air conditioners are tested in the laboratory before being sold to users. In order to ensure that the air conditioner can adapt to different environments, the static pressure range value tested in advance should meet the needs of all user environments. For example, the environment in the factory is different from the indoor environment in a normal home. The length, surface roughness, curvature, etc. of the air conditioner are also different for different environments. Therefore, the static pressure range of the air conditioner for the factory environment is one range value, while the static pressure range of the air conditioner for the indoor environment in a normal home is another range value.

[0041] Different static pressure values ​​include P1, P2, P3...P n The difference between two adjacent static pressure values ​​is ΔP, where ΔP = P. n -P n-1 ΔP is a constant.

[0042] Preferably, the static pressure value can be a constant value, which is the difference between two consecutive static pressure values, to facilitate subsequent linear fitting. Of course, the difference between two consecutive static pressure values ​​can also be a variable value to ensure the comprehensiveness of the data test.

[0043] The conditions for setting the constant air volume adjustment program execution include one or more of the following: timed entry, remote control entry, and entry during the first run after each air conditioner is turned on.

[0044] There are many ways to set the execution conditions for the constant air volume adjustment program. Specifically, it can be entered by timed entry, remote control entry, or entry during the first run after the air conditioner is turned on. The diverse options can meet different user needs, or the corresponding entry method can be set according to the different environments in which the air conditioner is located.

[0045] Increase the motor speed ΔX at regular intervals, including according to X. k-1 After running at a speed of t seconds, according to X k The rotational speed operates for t seconds, and X k =X k-1 +△X.

[0046] Within a time interval of t seconds, the motor current and motor speed can be detected to make the detected data more accurate.

[0047] Depending on the environment in which the air conditioner is located, the corresponding parameter X... max X0, △X, and t can all be set accordingly.

[0048] Because the environment in which an air conditioner is located varies—it may be in a regular room, a factory, a rented room, etc.—the corresponding parameters can be adjusted and set according to the on-site environment.

[0049] In step S2, the default motor speed in the program is one of 600, 750, 800, 900, 1000, 1050, or 1200 rpm.

[0050] The default motor speed can be selected from the above speeds. When the conditions for executing the constant air volume adjustment program are not met, the system selects the speed corresponding to the user's air volume setting.

[0051] The air conditioner has a constant air volume mode, and in the constant air volume mode there are multiple fan speeds, each fan speed corresponding to a constant air volume.

[0052] It enables the air conditioner to achieve a constant air volume, and there are multiple fan speeds in the constant air volume mode, which can be switched to change the constant air volume.

[0053] A storage device for executing a constant airflow control method includes: a storage module for storing fitting coefficients a from step S1. i b i The rotational speed X used to store the rotational speed in step S4 k， Current Y k and the i intersection points stored in step S5; a calculation module for fitting y=a in step S1. i x+b i Fitting y=c in step S4 x+d and the calculation of y=c in step S5. x+d and y=a i x+b i The i intersection points.

[0054] An air conditioner, including a constant air volume control method.

[0055] 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 constant air volume control method, characterized in that, The steps include the following: S1: Pre-determined static pressure P i Obtain a constant air volume C i When the motor current y and motor speed x are fitted together, the result is obtained at a constant airflow of C. i At that time, the linear relationship between the motor current y and the motor speed x for n groups under different static pressures is: y = a i x+b i， Where i = 1, 2, 3...n; and the fitting coefficient a i b i Stored in a device with storage functionality; S2: When the air conditioner is running, if the conditions for executing the constant air volume adjustment program are met, proceed to S3; otherwise, when the user sets the fan speed, select the default motor speed from the program. S3: Set the initial motor speed X0. After a certain period of time, increase the motor speed ΔX and record the current motor current Y. k、 Motor speed X k， Until the maximum speed X is reached max， Where k = 0, 1, 2, 3…n; when k > 1, X k= X k-1 +△X; S4: Record the rotational speed X k， Current Y k By performing linear fitting, the relationship between motor current y and motor speed x is obtained as y=c x+d; S5: The controller calculates y=c x+d and y=a i x+b i The i intersection points are obtained (X) i ,Y i ); S6: When the user sets the wind speed, the corresponding motor speed calculated in step S5 will be used for operation.

2. The constant air volume control method according to claim 1, characterized in that, In step S1, the air conditioner is pre-measured at static pressure P before being factory-set. i Obtain a constant air volume C i At that time, the corresponding motor current y and motor speed x are used, and the fitting coefficient a is used to determine the relationship between them. i b i Stored in a device with storage functionality.

3. The constant air volume control method according to claim 1, characterized in that, The different static pressures include P1, P2, P3...P n The difference between two adjacent static pressures is ΔP, where ΔP = P. n -P n-1 The ΔP is a constant value.

4. The constant air volume control method according to claim 1, characterized in that, The execution conditions for the constant air volume adjustment program include one or more of the following: timed entry, remote control entry, and entry during the first run after each air conditioner is turned on.

5. The constant air volume control method according to claim 1, characterized in that, The phrase "increasing the motor speed ΔX at regular intervals" includes according to X k-1 After running at a speed of t seconds, according to X k The rotational speed operates for t seconds, and X k =X k-1 +△X.

6. The constant air volume control method according to claim 5, characterized in that, Depending on the environment in which the air conditioner is located, the corresponding parameter X... max X0, △X, and t can all be set accordingly.

7. The constant air volume control method according to claim 1, characterized in that, In step S2, the default motor speed in the program is one of 600, 750, 800, 900, 1000, 1050, or 1200 rpm.

8. The constant air volume control method according to claim 1, characterized in that, The air conditioner has a constant air volume mode and multiple fan speeds in the constant air volume mode, each fan speed corresponding to a constant air volume.

9. A storage device, characterized in that, Performing the constant air volume control method as described in any one of claims 1-8, comprising: Storage module for storing the fitting coefficients a from step S1. i b i The rotational speed X used to store the rotational speed in step S4 k， Current Y k And the i intersection points stored in step S5; The calculation module is used to fit y=a in step S1. i x+b i Fitting y=c in step S4 x+d and the calculation of y=c in step S5. x+d and y=a i x+b i The i intersection points.

10. An air conditioner, characterized in that, This includes the constant air volume control method as described in any one of claims 1-8.

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