Water treatment device, its control method, device and readable storage medium

Abstract

The present invention provides a water treatment device, a control method, a device and a readable storage medium thereof. The control method of the water treatment device includes: receiving a set value of the outlet water temperature; obtaining historical operation information of the water treatment device, where the historical operation information includes collected values of the actual outlet water flow rate and the outlet water temperature; inputting the actual outlet water flow rate and the collected value into a state observer to obtain a first estimated value of the outlet water temperature and a second estimated value of an unknown disturbance output by the state observer; determining a control value of the outlet water flow rate according to the set value, the first estimated value and the second estimated value; and controlling the operation of the pump body of the water treatment device according to the control value. By operating this control method, the complexity of parameter adjustment is reduced. At the same time, the above technical solution can also improve the accuracy of the outlet water temperature of the water treatment device.

Description

Technical Field

[0001] The present invention relates to the field of control technologies, and more particularly, to a water treatment device, a control method and device thereof, and a readable storage medium. Background Art

[0002] The temperature control of an instant hot water dispenser is restricted by the environment, the water pump, etc., as well as the number of sensors. During the debugging stage, all scenarios need to be considered comprehensively, and the corresponding parameters need to be adjusted separately to improve the accuracy of the controlled outlet water temperature, resulting in a complex temperature control process. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related technologies.

[0004] To this end, a first aspect of the present invention provides a control method for a water treatment device.

[0005] A second aspect of the present invention provides a control device for a water treatment device.

[0006] A third aspect of the present invention provides a readable storage medium.

[0007] A fourth aspect of the present invention provides a water treatment device.

[0008] In view of this, according to the first aspect of the present invention, a control method for a water treatment device is provided, including: receiving a set value of the outlet water temperature; obtaining historical operation information of the water treatment device, where the historical operation information includes collected values of the actual outlet water flow rate and the outlet water temperature; inputting the actual outlet water flow rate and the collected value into a state observer to obtain a first estimated value of the outlet water temperature and a second estimated value of an unknown disturbance output by the state observer; determining a control value of the outlet water flow rate according to the set value, the first estimated value, and the second estimated value; and controlling the operation of the pump body of the water treatment device according to the control value.

[0009] The technical solution of the present application proposes a control method for a water treatment device. Specifically, the collected values of the actual outlet water flow rate and the outlet water temperature are input into a state observer, and the state observer is used to estimate and compensate for the "unknown total disturbance" to obtain a first estimated value and a second estimated value output by the state observer. During the control process of the outlet water temperature, a control value of the outlet water flow rate is determined according to the set value of the outlet water temperature, the first estimated value, and the second estimated value output by the state observer, and the operation of the pump body is controlled according to the control value.

[0010] By running this control method, all the uncertain disturbances affecting the outlet water temperature are classified as "unknown total disturbances", and the "unknown total disturbances" are estimated and compensated using the actual input and output data of the controlled object, thereby reducing the complexity of parameter tuning. At the same time, adopting the above technical solution can also improve the accuracy of the outlet water temperature of the water treatment device.

[0011] In the above technical solution, the set value of the outlet water temperature can be understood as the set outlet water temperature, which can be set according to the actual usage requirements of the water treatment device.

[0012] In any of the above technical solutions, the set outlet water temperature, that is, the set value, can be selected as 45°C, 55°C, 75°C or 100°C.

[0013] In the above solution of the present application, the accuracy of the outlet water temperature of the water treatment device is improved by controlling the outlet water flow. Therefore, the outlet water temperature T out As the controlled quantity in the present application, the outlet water flow F belongs to the control quantity. According to the law of conservation of energy, the heat exchange model expression between the heating bucket and water can be obtained as:

[0014]

[0015] Among them, ρ is the water density; V is the volume of the heating bucket; C e is the specific heat capacity of water; T ch is the temperature of the heating bucket wall; T i is the inlet water temperature; R v is the thermal resistance of the heating bucket, and T i 、T out are collected by the temperature sensor.

[0016] Since the flow rate F and the outlet water temperature T out are in a non-linear relationship, the control quantity input is designed as u = F(T out - T i ), and the controlled quantity output is T out .

[0017] For this control strategy, the object of the instant-heating water dispenser can be approximated as a first-order object, and the approximate transfer function is expressed as follows:

[0018]

[0019] By changing the heat exchange model expression, the following expression can be obtained:

[0020]

[0021] Another u = F(T out - T i), the object formula can be obtained as follows:

[0022]

[0023] Introduce the extended state variable x 2 , let x 2 = f, then the controlled object system is:

[0024]

[0025] Introduce the estimated value z 1 of the state quantity x 1 , x 2 of the estimated value z 2 , and take the difference between x 1 and z 1 as the observation error e 1 .

[0026] Adopt the method proposed by Professor Gao Zhiqiang in 2003 to linearize the extended state observer into a linear extended state observer, and its formula is as follows:

[0027]

[0028] Select appropriate observer control parameters, and the observation error e 1 can be made 0. At this time, z 1 ≈ x 1 , z 2 ≈ x 2 , let u 0 = ω c (e 1 , p), where p is a set of parameters, which can be understood as determining the value of ω 1 according to the magnitude of e c . Design the disturbance compensation part, and its formula is as follows:

[0029] Then the control law is:

[0030]

[0031] At this time, the system becomes a "linear integral series type" system.

[0032] The parameters that need to be tuned are β 1 , β 2 , b, ω c , and the first two parameters use the bandwidth method proposed by Professor Gao Zhiqiang, β 1 = 2ω 0 , β 2 = ω 0 2 , by adjusting the parameter ω0 That's all. The parameter b is the reciprocal of the volume of the heat pipe. At this time, the only observer parameters to be tuned are the bandwidth ω 0 and the controller parameter ω c . And for the tuning of the bandwidth ω 0 , only the degree of z 1 tracking the controlled variable y(x 1 ) needs to be concerned. When z 1 can track y well, it is the appropriate bandwidth parameter ω 0 .

[0033] In any of the above technical solutions, the product of the actual water output flow rate and the collected value is used as the input of the state observer to obtain the first estimated value and the second estimated value.

[0034] In this technical solution, by limiting the product of the water flow rate and the collected value as the input of the state observer, the problem of amplitude limiting existing in the flow rate input is eliminated. At the same time, it also avoids integral saturation and improves the control accuracy of the water output flow rate.

[0035] In addition, the control method of the water treatment device proposed in this application also has the following additional technical features.

[0036] In the above technical solution, determining the control value of the water output flow rate according to the set value, the first estimated value and the second estimated value includes: obtaining the volume value of the heating barrel of the water treatment device and the target control parameter value of the state observer; determining the deviation value between the set value and the first estimated value; determining the product value of the deviation value and the target control parameter value; using the product of the difference between the product value and the second estimated value and the volume value as the control value.

[0037] In this technical solution, the specific calculation method of the control value is defined, and the control value can be directly calculated according to the above calculation method.

[0038] In the above technical solution, the heating barrel is used to heat the liquid to be heated stored in the heating barrel to output the heated liquid to be heated.

[0039] In one of the technical solutions, the liquid to be heated can be water.

[0040] In one of the technical solutions, the volume value can be understood as the volume of the liquid to be heated that the heating barrel can hold, and this volume value belongs to the inherent parameter of the heating barrel.

[0041] In one of the technical solutions, the target control parameter value, which is a parameter during the operation of the state observer, where this parameter is similar to the error gain term of the PID algorithm (Proportion Integral Differential).

[0042] In one of the technical solutions, the deviation value can be understood as the difference between the set value and the first estimated value.

[0043] In one of the technical solutions, it further includes: obtaining at least two candidate control parameter values; determining the target control parameter value from the at least two candidate control parameter values according to the magnitude of the deviation value.

[0044] In this technical solution, for the water treatment device, the larger the target control parameter value, the stronger the feedback effect, the faster the error between the set value and the first estimated value is eliminated, and the faster the temperature rises. At the same time, the magnitude of the target control parameter value will also affect the overshoot. The larger the target control parameter value, the larger the overshoot. In order to reduce the overshoot, the target control parameter value will be smaller. However, when the target control parameter value is small, it will cause the problem of slow temperature recovery.

[0045] Based on this, the technical solution of the present application obtains two or more candidate control parameter values and selects the target control parameter value from the candidate control parameter values according to the deviation value, so as to change the target control parameter value with a fixed value into a dynamic one.

[0046] In any of the above technical solutions, the deviation value and the target control parameter value directly conform to a piecewise linear relationship, so as to achieve the selection effect of "large error, small gain; small error, large gain".

[0047] In the above technical solution, "large error" and "small error" are relative concepts. Similarly, "large gain" and "small gain" are also relative concepts. For example, at the first error, the first gain is selected, and at the second error, the second gain is selected, where the first error is greater than the second error and the first gain is less than the second gain.

[0048] In the above technical solution, the error refers to the deviation value.

[0049] In the above technical solution, the candidate control parameter value can be the default set value or can be set according to the actual use scenario of the water treatment device.

[0050] In any of the above technical solutions, each candidate control parameter value corresponds to a deviation interval, and the control method further includes: determining the deviation interval corresponding to the deviation value; determining the target control parameter value according to the correspondence between the deviation interval and the candidate control parameter value.

[0051] In this technical solution, the determination method of the target control parameter value is defined. By setting a deviation interval for each candidate control parameter value, after determining the deviation value, the deviation interval corresponding to the target control parameter value can be determined according to the upper and lower limits of the deviation value and the deviation interval, so as to obtain the target control parameter value after determining the deviation interval corresponding to the target control parameter value.

[0052] In any of the above technical solutions, the deviation value is negatively correlated with the target control parameter value.

[0053] In any of the above technical solutions, before obtaining the historical operation information of the water treatment device, it further includes: obtaining the inlet water temperature value of the water treatment device; controlling the operation of the pump body based on the set value being less than or equal to the inlet water temperature value.

[0054] In this technical solution, by obtaining the inlet water temperature value, the inlet water temperature value is compared with the set value, and then it is judged whether the liquid to be heated needs to be heated to discharge water, that is, it is judged whether there is a heating requirement before discharging water. When the set value is lower than the inlet water temperature value, it is considered that the current water treatment device does not need to heat the liquid to be heated. At this time, the operation of the pump body can be controlled to achieve direct water discharge.

[0055] Based on the set value being higher than the inlet water temperature value, perform the "obtaining the historical operation information of the water treatment device" and subsequent control steps.

[0056] In any of the above technical solutions, controlling the operation of the pump body of the water treatment device according to the control value specifically includes: determining the voltage duty ratio of the pump body according to the control quantity; controlling the operation of the pump body according to the voltage duty ratio.

[0057] In this technical solution, considering that the control quantity cannot be directly used to control the pump body, at this time, the control quantity can be converted into a voltage duty ratio capable of controlling the operation of the pump body to achieve the control of the pump body.

[0058] In the above technical solution, the voltage duty ratio can be a pulse width modulation signal.

[0059] The second aspect of the present invention lies in providing a control device for a water treatment device, including: a receiving unit for receiving a set value of the outlet water temperature; a first obtaining unit for obtaining the historical operation information of the water treatment device, wherein the historical operation information includes the collected values of the actual outlet water flow rate and the outlet water temperature; a second obtaining unit for inputting the actual outlet water flow rate and the collected value into a state observer to obtain a first estimated value of the outlet water temperature and a second estimated value of an unknown disturbance output by the state observer; a determining unit for determining a control value of the outlet water flow rate according to the set value, the first estimated value and the second estimated value; a control unit for controlling the operation of the pump body of the water treatment device according to the control value.

[0060] The technical solution of this application proposes a control device for a water treatment device. Specifically, the collected values of the actual water output flow rate and the water output temperature are input into a state observer, and the state observer is used to estimate and compensate for the "unknown total disturbance", so as to obtain the first estimated value and the second estimated value output by the state observer. During the control process of the water output temperature, the control value of the water output flow rate is determined according to the set value of the water output temperature, the first estimated value and the second estimated value output by the state observer, and the operation of the pump body is controlled according to this control value.

[0061] By operating this control method, all uncertain disturbances affecting the water output temperature are attributed to the "unknown total disturbance", and the "unknown total disturbance" is estimated and compensated using the actual input and output data of the controlled object, thereby reducing the complexity of parameter adjustment. At the same time, adopting the above technical solution can also improve the accuracy of the water output temperature of the water treatment device.

[0062] In the above technical solution, the set value of the water output temperature can be understood as the set water output temperature, which can be set according to the actual use requirements of the water treatment device.

[0063] In any of the above technical solutions, the set water output temperature, that is, the set value, can be selected as 45°C, 55°C, 75°C or 100°C.

[0064] In the above technical solution, the determination unit is specifically used for: obtaining the volume value of the heating barrel of the water treatment device and the target control parameter value of the state observer; determining the deviation value between the set value and the first estimated value; determining the product value of the deviation value and the target control parameter value; taking the product of the difference between the product value and the second estimated value and the volume value as the control value.

[0065] In this technical solution, the specific calculation method of the control value is defined, and the control value can be directly calculated according to the above calculation method.

[0066] In the above technical solution, the heating barrel is used to heat the liquid to be heated stored in the heating barrel so as to output the heated liquid to be heated.

[0067] In one of the technical solutions, the liquid to be heated can be water.

[0068] In one of the technical solutions, the volume value can be understood as the volume of the liquid to be heated that the heating barrel can hold, and this volume value belongs to the inherent parameter of the heating barrel.

[0069] In one of the technical solutions, the target control parameter value, which is a parameter of the state observer during operation, is similar to the error gain term of the PID algorithm (Proportion Integral Differential). In one of the technical solutions, the deviation value can be understood as the difference between the set value and the first estimated value.

[0070] In any of the above technical solutions, the determination unit is further configured to: obtain at least two candidate control parameter values; and determine the target control parameter value from the at least two candidate control parameter values according to the magnitude of the deviation value.

[0071] In this technical solution, for the water treatment device, the larger the target control parameter value, the stronger the feedback effect, the faster the error between the set value and the first estimated value is eliminated, and the faster the temperature rises. At the same time, the magnitude of the target control parameter value also affects the overshoot. The larger the target control parameter value, the larger the overshoot. In order to reduce the overshoot, the target control parameter value will be smaller. However, when the target control parameter value is small, it will cause the problem of slow temperature recovery.

[0072] Based on this, the technical solution of the present application obtains two or more candidate control parameter values and selects the target control parameter value from the candidate control parameter values according to the deviation value, so as to change the target control parameter value with a fixed value into a dynamic one.

[0073] In any of the above technical solutions, the deviation value and the target control parameter value directly conform to a piecewise linear relationship, so as to achieve the selection effect of "large error, small gain, small error, large gain".

[0074] In the above technical solution, "large error" and "small error" are relative concepts. Similarly, "large gain" and "small gain" are also relative concepts. For example, at the first error, the first gain is selected, and at the second error, the second gain is selected, where the first error is greater than the second error and the first gain is less than the second gain.

[0075] In the above technical solution, the error refers to the deviation value.

[0076] In the above technical solution, the candidate control parameter value can be the default set value or can be set according to the actual usage scenario of the water treatment device.

[0077] In any of the above technical solutions, each candidate control parameter value corresponds to a deviation interval, and the determination unit is further configured to: determine the deviation interval corresponding to the deviation value; and determine the target control parameter value according to the corresponding relationship between the deviation interval and the candidate control parameter value.

[0078] In this technical solution, the determination method of the target control parameter value is defined. By setting a deviation interval for each candidate control parameter value, after determining the deviation value, the deviation interval corresponding to the target control parameter value can be determined according to the upper and lower limits of the deviation interval, so that after determining the deviation interval corresponding to the target control parameter value, the target control parameter value can be obtained.

[0079] In any of the above technical solutions, the deviation value is negatively correlated with the target control parameter value.

[0080] In any of the above technical solutions, the determination unit is further configured to: obtain the inlet water temperature value of the water treatment device; and control the pump body to operate based on the set value being less than or equal to the inlet water temperature value.

[0081] In this technical solution, by obtaining the inlet water temperature value, the inlet water temperature value is compared with the set value, and then it is judged whether the liquid to be heated needs to be heated to discharge water, that is, it is judged whether there is a heating requirement before discharging water. When the set value is lower than the inlet water temperature value, it is considered that the current water treatment device does not need to heat the liquid to be heated. At this time, the pump body can be controlled to operate to achieve direct water discharge.

[0082] Based on the set value being higher than the inlet water temperature value, the control steps of "obtaining the historical operation information of the water treatment device" and subsequent steps are executed.

[0083] In any of the above technical solutions, the control unit is further configured to: determine the voltage duty ratio of the pump body according to the control amount; and control the pump body to operate according to the voltage duty ratio.

[0084] In this technical solution, considering that the control amount cannot be directly used to control the pump body, at this time, the control amount can be converted into a voltage duty ratio capable of controlling the pump body to operate, so as to realize the control of the pump body.

[0085] In the above technical solution, the voltage duty ratio can be a pulse width modulation signal.

[0086] The third aspect of the present invention lies in providing a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the steps of the control method of the water treatment device as described in any one of the above are realized.

[0087] The fourth aspect of the present invention lies in providing a water treatment device, including: a heating barrel; a pump body located on the water inlet pipeline of the heating barrel; a control device of the water treatment device as described above; or a readable storage medium as described above.

[0088] In any of the above technical solutions, it further includes: a first detector located at the water inlet of the heating barrel for obtaining the inlet water temperature value; a second detector located at the water outlet of the heating barrel for obtaining the collected value.

[0089] In any of the above technical solutions, it further includes: a liquid storage tank, which is communicated with the water inlet pipeline of the heating barrel and is used for supplying liquid to the heating barrel.

[0090] In any of the above technical solutions, the water treatment device includes any one of a water purifier, a water dispenser, and a water heater.

[0091] The additional aspects and advantages of the present invention will be partly given in the following description, partly will become obvious from the following description, or will be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0092] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

[0093] Figure 1 FIG. 1 shows one of the schematic flowcharts of the control method of the water treatment device in the embodiment of the present invention;

[0094] Figure 2 FIG. 2 shows the schematic flowchart of determining the control value of the water output flow according to the set value, the first estimated value, and the second estimated value in the embodiment of the present invention;

[0095] Figure 3 FIG. 3 shows another schematic flowchart of the control method of the water treatment device in the embodiment of the present invention;

[0096] Figure 4 FIG. 4 shows the schematic block diagram of the control device of the water treatment device in the embodiment of the present invention;

[0097] Figure 5 FIG. 5 shows the schematic diagram of the control logic of the water treatment device in the embodiment of the present invention;

[0098] Figure 6 FIG. 6 shows the schematic block diagram of the water treatment device in the embodiment of the present invention;

[0099] Figure 7 FIG. 7 shows the structural schematic diagram of the water treatment device in the embodiment of the present invention.

[0100] Wherein, Figure 7 the corresponding relationship between the reference numerals in the drawings and the component names is:

[0101] 602 is the heating barrel, 604 is the pump body, 606 is the first sensor, 608 is the second sensor, and 610 is the liquid storage tank. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0102] In order to more clearly understand the above aspects, features, and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

[0103] In the following description, many specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention may be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited by the specific embodiments disclosed below.

[0104] Embodiment 1

[0105] As Figure 1 shown, according to the first aspect of the present invention, the present invention provides a control method for a water treatment device, including:

[0106] Step 102, receiving a set value of the outlet water temperature;

[0107] Step 104, obtaining historical operation information of the water treatment device;

[0108] Step 106, inputting the actual outlet water flow rate and the collected value into a state observer to obtain a first estimated value of the outlet water temperature and a second estimated value of the unknown disturbance output by the state observer;

[0109] Step 108, determining a control value of the outlet water flow rate according to the set value, the first estimated value, and the second estimated value;

[0110] Step 110, controlling the operation of the pump body of the water treatment device according to the control value.

[0111] Wherein, the historical operation information includes the collected values of the actual outlet water flow rate and the outlet water temperature.

[0112] An embodiment of the present application proposes a control method for a water treatment device. Specifically, the collected values of the actual outlet water flow rate and the outlet water temperature are input into a state observer, and the state observer is used to estimate and compensate for the "unknown total disturbance", so as to obtain a first estimated value and a second estimated value output by the state observer. During the control process of the outlet water temperature, the control value of the outlet water flow rate is determined according to the set value of the outlet water temperature, the first estimated value, and the second estimated value output by the state observer, and the operation of the pump body is controlled according to the control value.

[0113] By operating this control method, all uncertain disturbances affecting the outlet water temperature are attributed to the "unknown total disturbance", and the "unknown total disturbance" is estimated and compensated using the actual input-output data of the controlled object, thereby reducing the complexity of parameter adjustment. At the same time, the above embodiment can also improve the accuracy of the outlet water temperature of the water treatment device.

[0114] In the above embodiments, the set value of the outlet water temperature can be understood as setting the outlet water temperature, which can be set according to the actual usage requirements of the water treatment device.

[0115] In any of the above embodiments, the set outlet water temperature, that is, the set value, can be selected as 45°C, 55°C, 75°C or 100°C.

[0116] In the above solution of the present application, the accuracy of the outlet water temperature of the water treatment device is improved by controlling the outlet water flow. Therefore, the outlet water temperature T out As the controlled quantity in the present application, the outlet water flow F belongs to the control quantity. According to the law of conservation of energy, the heat exchange model expression between the heating barrel and water can be obtained as:

[0117]

[0118] Among them, ρ is the water density; V is the volume of the heating barrel; C e is the specific heat capacity of water; T ch is the temperature of the heating barrel wall; T i is the inlet water temperature; R v is the thermal resistance of the heating barrel, and T i , T out are collected by the temperature sensor.

[0119] Since the flow rate F and the outlet water temperature T out are in a non-linear relationship, the control quantity input is designed as u = F(T out - T i ), and the controlled quantity output is T out .

[0120] For this control strategy, as Figure 5 shown, the instant-heating type water dispenser object can be approximated as a first-order object, and the approximate transfer function is expressed as follows:

[0121]

[0122] By changing the heat exchange model expression, the following expression can be obtained:

[0123]

[0124] Another u = F(T out - T i ), and the object formula can be obtained as:

[0125]

[0126] Introduce the extended state variable x 2 , and let x2 = f, then the controlled object system is:

[0127]

[0128] Introduce the state variable x 1 estimator z 1 , x 2 estimator z 2 , and take the difference between x 1 and z 1 as the observation error e 1 , and adopt the method proposed by Professor Gao Zhiqiang in 2003 to linearize the extended state observer into a linear extended state observer, and its formula is as follows:

[0129]

[0130] Select appropriate observer control parameters, and the observation error e 1 can be made 0. At this time, z 1 ≈ x 1 , z 2 ≈ x 2 ,

[0131] Let u 0 = ω c (e 1 , p), where p is a set of parameters, which can be understood as determining the value of ω 1 according to the magnitude of e c .

[0132] Design the disturbance compensation part, and its formula is as follows:

[0133] Then the control law is:

[0134]

[0135] At this time, the system becomes a "linear integral series type" system.

[0136] The parameters that need to be tuned are β 1 , β 2 , b, ω c . For the first two parameters, use the bandwidth method proposed by Professor Gao Zhiqiang, β 1 = 2ω 0 , β 2 = ω 0 2 . By adjusting the parameter ω 0 it can be done. The parameter b is the reciprocal of the volume of the heat pipe. At this time, the only observer parameter that needs to be tuned is the bandwidth ω 0 and the controller parameter ω c . And the bandwidth ω0 The tuning only needs to focus on z 1 Tracking the controlled variable y(x 1 ) to the extent that when z 1 Can track y well, it is the appropriate bandwidth parameter ω 0 .

[0137] In any of the above embodiments, the product of the actual effluent flow rate and the collected value is used as the input of the state observer to obtain the first estimated value and the second estimated value.

[0138] In this embodiment, by defining the product of the water flow rate and the collected value as the input of the state observer, the problem of amplitude limitation existing in the flow rate input is eliminated. At the same time, it also plays a role in avoiding integral saturation and improving the control accuracy of the effluent flow rate.

[0139] Embodiment 2

[0140] In one of the embodiments, as Figure 2 shown, determining the control value of the effluent flow rate according to the set value, the first estimated value and the second estimated value includes:

[0141] Step 202, obtaining the volume value of the heating barrel of the water treatment device and the target control parameter value of the state observer;

[0142] Step 204, determining the deviation value between the set value and the first estimated value;

[0143] Step 206, determining the product value of the deviation value and the target control parameter value;

[0144] Step 208, taking the product of the difference between the product value and the second estimated value and the volume value as the control value.

[0145] In this embodiment, the specific calculation method of the control value is defined, and the control value can be directly calculated according to the above calculation method.

[0146] In the above embodiments, the heating barrel is used to heat the liquid to be heated stored in the heating barrel to output the heated liquid to be heated. In one of the embodiments, the liquid to be heated can be water.

[0147] In one of the embodiments, the volume value can be understood as the volume of the heating barrel that can hold the liquid to be heated, and this volume value belongs to the inherent parameter of the heating barrel.

[0148] In one of the embodiments, the target control parameter value, that is, a parameter in the operation process of the state observer, where this parameter is similar to the error gain term of the PID algorithm (Proportion Integral Differential).

[0149] In one embodiment, the deviation value can be understood as the difference between the set value and the first estimated value.

[0150] In one embodiment, it further includes: obtaining at least two candidate control parameter values; determining a target control parameter value from the at least two candidate control parameter values according to the magnitude of the deviation value.

[0151] In this embodiment, for a water treatment device, the larger the target control parameter value, the stronger the feedback effect, the faster the error between the set value and the first estimated value is eliminated, and the faster the temperature rises. At the same time, the magnitude of the target control parameter value will also affect the overshoot. The larger the target control parameter value, the larger the overshoot. In order to reduce the overshoot, the target control parameter value will be smaller. However, when the target control parameter value is smaller, it will cause the problem of slow temperature recovery.

[0152] Based on this, the embodiment of the present application obtains two or more candidate control parameter values and selects a target control parameter value from the candidate control parameter values according to the deviation value, so as to change the target control parameter value with a fixed value into a dynamic one.

[0153] In any of the above embodiments, the deviation value and the target control parameter value directly conform to a piecewise linear relationship, so as to achieve the selection effect of "large error, small gain; small error, large gain".

[0154] In the above embodiments, "large error" and "small error" are relative concepts. Similarly, "large gain" and "small gain" are also relative concepts. For example, at the first error, the first gain is selected, and at the second error, the second gain is selected, where the first error is greater than the second error and the first gain is less than the second gain.

[0155] In the above embodiments, the error refers to the deviation value.

[0156] In the above embodiments, the candidate control parameter value can be the default set value or can be set according to the actual usage scenario of the water treatment device.

[0157] In any of the above embodiments, each candidate control parameter value corresponds to a deviation interval, and the control method further includes: determining the deviation interval corresponding to the deviation value; determining the target control parameter value according to the correspondence between the deviation interval and the candidate control parameter value.

[0158] In this embodiment, the determination method of the target control parameter value is defined. By setting a deviation interval for each candidate control parameter value, after the deviation value is determined, the deviation interval corresponding to the target control parameter value can be determined according to the upper and lower limits of the deviation value and the deviation interval, so as to obtain the target control parameter value after determining the deviation interval corresponding to the target control parameter value.

[0159] In any of the above embodiments, the deviation value is negatively correlated with the target control parameter value.

[0160] Embodiment III

[0161] In one of the embodiments, before obtaining the historical operation information of the water treatment device, it further includes: obtaining the inlet water temperature value of the water treatment device; controlling the operation of the pump body based on the set value being less than or equal to the inlet water temperature value.

[0162] In this embodiment, by obtaining the inlet water temperature value, the inlet water temperature value is compared with the set value, and then it is determined whether the liquid to be heated needs to be heated to discharge water, that is, it is determined whether there is a heating requirement before discharging water. When the set value is lower than the inlet water temperature value, it is considered that the current water treatment device does not need to heat the liquid to be heated. At this time, the operation of the pump body can be controlled to achieve direct water discharge.

[0163] Based on the set value being higher than the inlet water temperature value, execute the steps of "obtaining the historical operation information of the water treatment device" and subsequent control steps.

[0164] Embodiment IV

[0165] In any of the above embodiments, controlling the operation of the pump body of the water treatment device according to the control value specifically includes: determining the voltage duty ratio of the pump body according to the control amount; controlling the operation of the pump body according to the voltage duty ratio.

[0166] In this embodiment, considering that the control amount cannot be directly used to control the pump body, at this time, the control amount can be converted into a voltage duty ratio that can control the operation of the pump body to achieve the control of the pump body.

[0167] In the above embodiments, the voltage duty ratio can be a pulse width modulation signal.

[0168] Embodiment V

[0169] As Figure 3 shown, the control method of the water treatment device includes:

[0170] Step 302, receive the set outlet water temperature r;

[0171] Step 304, determine whether it is normal temperature water. If the determination result is yes, execute step 306; if the determination is no, execute step 308;

[0172] Step 306, directly discharge water;

[0173] Step 308, subtract the first estimated value output by the state observer from the outlet water temperature r to obtain e 1 ;

[0174] Step 310, calculate the control amount

[0175] Step 312: Calculate the water flow rate and voltage duty ratio according to the control quantity u to control the operation of the pump body;

[0176] Step 314: Input the collected values of the actual water flow rate and water outlet temperature into the state observer to obtain a new first estimated value and a new second estimated value;

[0177] Step 316: Determine whether to stop the water outlet. If the determination result is yes, end; if the determination result is no, repeat step 308.

[0178] In this embodiment, the control quantity is also the control value in the above text.

[0179] In this embodiment, by determining whether to stop the water outlet, the control of the water outlet temperature and the water output is combined to meet the user's water use requirements.

[0180] Embodiment Six

[0181] In one of the embodiments, as Figure 4 shown, a control device 400 for a water treatment device is provided, including: a receiving unit 402 for receiving a set value of the water outlet temperature; a first obtaining unit 404 for obtaining historical operation information of the water treatment device, where the historical operation information includes collected values of the actual water flow rate and water outlet temperature; a second obtaining unit 406 for inputting the actual water flow rate and the collected value into a state observer to obtain a first estimated value of the water outlet temperature and a second estimated value of an unknown disturbance output by the state observer; a determining unit 408 for determining a control value of the water flow rate according to the set value, the first estimated value, and the second estimated value; and a control unit 410 for controlling the operation of the pump body of the water treatment device according to the control value.

[0182] An embodiment of the present application proposes a control device for a water treatment device. Specifically, the collected values of the actual water flow rate and the water outlet temperature are input into a state observer, and the state observer is used to estimate and compensate for the "unknown total disturbance", so as to obtain a first estimated value and a second estimated value output by the state observer. During the control process of the water outlet temperature, the control value of the water flow rate is determined according to the set value of the water outlet temperature, the first estimated value, and the second estimated value output by the state observer, and the operation of the pump body is controlled according to the control value.

[0183] By running this control method, all uncertain disturbances affecting the water outlet temperature are attributed to the "unknown total disturbance", and the "unknown total disturbance" is estimated and compensated using the actual input and output data of the controlled object, thereby reducing the complexity of parameter adjustment. At the same time, the above embodiment can also improve the accuracy of the water outlet temperature of the water treatment device.

[0184] In the above embodiments, the set value of the outlet water temperature can be understood as setting the outlet water temperature, which can be set according to the actual usage requirements of the water treatment device.

[0185] In any of the above embodiments, the set outlet water temperature, that is, the set value, can be selected as 45 °C, 55 °C, 75 °C or 100 °C.

[0186] In the above solution of the present application, the accuracy of the outlet water temperature of the water treatment device is improved by controlling the outlet water flow. Therefore, the outlet water temperature T out As the controlled quantity in the present application, the outlet water flow F belongs to the control quantity. According to the law of conservation of energy, the heat exchange model expression of the heating barrel and water can be obtained as:

[0187]

[0188] where ρ is the water density; V is the volume of the heating barrel; C e is the specific heat capacity of water; T ch is the temperature of the heating barrel wall; T i is the inlet water temperature; R v is the thermal resistance of the heating barrel, and T i , T out are collected by the temperature sensor.

[0189] Since the flow rate F and the outlet water temperature T out are non-linearly related, the control quantity input is designed as u = F(T out - T i ), and the controlled quantity output is T out .

[0190] For this control strategy, the object of the instant heating type water dispenser can be approximated as a first-order object, and the approximate transfer function is expressed as follows:

[0191]

[0192] By changing the heat exchange model expression, the following expression can be obtained:

[0193]

[0194] Another u = F(T out - T i ), and the object formula can be obtained as:

[0195]

[0196] Introduce the extended state variable x 2 , and let x 2= f, then the controlled object system is:

[0197]

[0198] Introduce the estimated value z of the state quantity x 1 and the estimated value z of x 1 , x 2 and the estimated value z of x 2 , and take the difference between x 1 and z 1 as the observation error e 1 .

[0199] Adopt the method proposed by Professor Gao Zhiqiang in 2003 to linearize the extended state observer into a linear extended state observer, and its formula is as follows:

[0200]

[0201] Select appropriate observer control parameters, and the observation error e 1 can be made 0. At this time, z 1 ≈ x 1 , z 2 ≈ x 2 , let u 0 = ω c (e 1 , p), where p is a set of parameters, which can be understood as determining the value of ω 1 according to the magnitude of e c .

[0202] Design the disturbance compensation part, and its formula is as follows:

[0203] Then the control law is:

[0204]

[0205] At this time, the system becomes a "linear integral series type" system.

[0206] The parameters to be tuned are β 1 , β 2 , b, ω c . For the first two parameters, use the bandwidth method proposed by Professor Gao Zhiqiang, β 1 = 2ω 0 , β 2 = ω 0 2 . By adjusting the parameter ω 0 , it is okay. The parameter b is the reciprocal of the volume of the heat pipe. At this time, the only observer parameter to be tuned is the bandwidth ω 0 and the controller parameter ω c . And the bandwidth ω 0The tuning only needs to focus on z 1 tracking the controlled variable y(x 1 ) to the extent that when z 1 can track y well, it is the appropriate bandwidth parameter ω 0 .

[0207] In any of the above embodiments, the product of the actual water output flow rate and the collected value is used as the input of the state observer to obtain a first estimated value and a second estimated value.

[0208] In this embodiment, by defining the product of the water flow rate and the collected value as the input of the state observer, the problem of amplitude limitation existing in the flow input is eliminated. At the same time, it also avoids integral saturation and improves the control accuracy of the water output flow rate.

[0209] In the above embodiment, the determining unit 408 is specifically configured to: obtain the volume value of the heating barrel of the water treatment device and the target control parameter value of the state observer; determine the deviation value between the set value and the first estimated value; determine the product value of the deviation value and the target control parameter value; and use the product of the difference between the product value and the second estimated value and the volume value as the control value.

[0210] In this embodiment, the specific calculation method of the control value is defined, and the control value can be directly calculated according to the above calculation method.

[0211] In the above embodiment, the heating barrel is used to heat the liquid to be heated stored in the heating barrel to output the heated liquid to be heated.

[0212] In one of the embodiments, the liquid to be heated can be water.

[0213] In one of the embodiments, the volume value can be understood as the volume of the liquid to be heated that the heating barrel can hold, and this volume value belongs to the inherent parameter of the heating barrel.

[0214] In one of the embodiments, the target control parameter value, which is a parameter during the operation of the state observer, where this parameter is similar to the error gain term of the PID algorithm (Proportion Integral Differential).

[0215] In one of the embodiments, the deviation value can be understood as the difference between the set value and the first estimated value.

[0216] In any of the above embodiments, the determining unit 408 is further configured to: obtain at least two candidate control parameter values; and determine the target control parameter value from the at least two candidate control parameter values according to the magnitude of the deviation value.

[0217] In this embodiment, for the water treatment device, the larger the target control parameter value, the stronger the feedback effect, the faster the error between the set value and the first estimated value is eliminated, and the faster the temperature rises. At the same time, the size of the target control parameter value also affects the overshoot. The larger the target control parameter value, the larger the overshoot. In order to reduce the overshoot, the target control parameter value will be smaller. However, when the target control parameter value is smaller, it will cause the problem of slow temperature recovery.

[0218] Based on this, the embodiment of the present application obtains two or more candidate control parameter values, and selects the target control parameter value from the candidate control parameter values according to the deviation value, so as to change the target control parameter value with a fixed value into a dynamic one.

[0219] In any of the above embodiments, the deviation value and the target control parameter value directly conform to a piecewise linear relationship, so as to achieve the selection effect of "large error, small gain, small error, large gain".

[0220] In the above embodiments, "large error" and "small error" are relative concepts. Similarly, "large gain" and "small gain" are also relative concepts. For example, at the first error, the first gain is selected, and at the second error, the second gain is selected, where the first error is greater than the second error and the first gain is less than the second gain.

[0221] In the above embodiments, the error refers to the deviation value.

[0222] In the above embodiments, the candidate control parameter value can be the default set value or can be set according to the actual usage scenario of the water treatment device.

[0223] In any of the above embodiments, each candidate control parameter value corresponds to a deviation interval, and the determination unit 408 is further configured to: determine the deviation interval corresponding to the deviation value; and determine the target control parameter value according to the correspondence between the deviation interval and the candidate control parameter value.

[0224] In this embodiment, the determination method of the target control parameter value is defined. By setting a deviation interval for each candidate control parameter value, after the deviation value is determined, the deviation interval corresponding to the target control parameter value can be determined according to the upper and lower limits of the deviation value and the deviation interval, so as to obtain the target control parameter value after determining the deviation interval corresponding to the target control parameter value.

[0225] In any of the above embodiments, the deviation value and the target control parameter value are negatively correlated.

[0226] In any of the above embodiments, the determination unit 408 is further configured to: obtain the inlet water temperature value of the water treatment device; and control the pump body to operate based on the set value being less than or equal to the inlet water temperature value.

[0227] In this embodiment, the inlet water temperature value is obtained to compare the inlet water temperature value with a set value, so as to determine whether the liquid to be heated needs to be heated before water outlet, that is, to determine whether there is a heating requirement before water outlet. When the set value is lower than the inlet water temperature value, it is considered that the current water treatment device does not need to heat the liquid to be heated. At this time, the pump body can be controlled to operate so as to achieve direct water outlet.

[0228] Based on the condition that the set value is higher than the inlet water temperature value, the steps of "obtaining the historical operation information of the water treatment device" and subsequent control steps are executed.

[0229] In any of the above embodiments, the control unit 410 is further configured to: determine the voltage duty ratio of the pump body according to the control quantity; control the operation of the pump body according to the voltage duty ratio.

[0230] In this embodiment, considering that the control quantity cannot be directly used to control the pump body, at this time, the control quantity can be converted into a voltage duty ratio capable of controlling the operation of the pump body, so as to achieve the control of the pump body.

[0231] In the above embodiment, the voltage duty ratio may be a pulse width modulation signal.

[0232] Embodiment Seven

[0233] In one of the embodiments, a readable storage medium is provided, and a program or instruction is stored on the readable storage medium. When the program or instruction is executed by a processor, the steps of the control method of the water treatment device as described in any one of the above are implemented.

[0234] In this embodiment, when the program or instruction is executed to implement the steps of the control method of the water treatment device as described above, the collected values of the actual water outlet flow rate and the water outlet temperature can be input into the state observer, and the state observer is used to estimate and compensate the "unknown total disturbance", so as to obtain the first estimated value and the second estimated value output by the state observer. During the control process of the water outlet temperature, the control value of the water outlet flow rate is determined according to the set value of the water outlet temperature, the first estimated value and the second estimated value output by the state observer, and the operation of the pump body is controlled according to the control value.

[0235] By running this control method, all the uncertain disturbances affecting the water outlet temperature are attributed to the "unknown total disturbance", and the "unknown total disturbance" is estimated and compensated using the actual input and output data of the controlled object, so as to reduce the complexity of parameter adjustment. At the same time, the above technical solution can also improve the accuracy of the water outlet temperature of the water treatment device.

[0236] Embodiment Eight

[0237] In one of the embodiments, as Figure 6 and Figure 7As shown, the present invention provides a water treatment device 600, including: a heating barrel 602; a pump body 604 located on the water inlet pipeline of the heating barrel 602; a control device 400 of the water treatment device as described above; or a readable storage medium as described above.

[0238] In this embodiment, the collected values of the actual water outlet flow rate and the water outlet temperature are input into the state observer, and the state observer is used to estimate and compensate for the "unknown total disturbance", so as to obtain a first estimated value and a second estimated value output by the state observer. During the control process of the water outlet temperature, the control value of the water outlet flow rate is determined according to the set value of the water outlet temperature, the first estimated value and the second estimated value output by the state observer, and the operation of the pump body 604 is controlled according to this control value.

[0239] By operating this control method, all uncertain disturbances affecting the water outlet temperature are attributed to the "unknown total disturbance", and the "unknown total disturbance" is estimated and compensated using the actual input and output data of the controlled object, thereby reducing the complexity of parameter adjustment. At the same time, the above technical solution can also improve the accuracy of the water outlet temperature of the water treatment device 600.

[0240] In the above technical solution, the set value of the water outlet temperature can be understood as the set water outlet temperature, which can be set according to the actual use requirements of the water treatment device 600.

[0241] In any of the above embodiments, a first sensor 606 is further included, which is arranged at the water inlet of the heating barrel 602 and is used to obtain the water inlet temperature.

[0242] In any of the above embodiments, a second sensor 608 is further included, which is arranged at the water outlet of the heating barrel 602 and is used to obtain the water outlet temperature.

[0243] In any of the above embodiments, a liquid storage tank 610 is further included, which is communicated with the water inlet pipeline of the heating barrel 602 and is used to supply liquid to the heating barrel 602.

[0244] In any of the above embodiments, the water treatment device 600 includes any one of a water purifier, a water dispenser, and a water heater.

[0245] In the description of the present invention, the term "a plurality of" means two or more, unless otherwise clearly defined. The orientation or positional relationship indicated by terms such as "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present invention; terms such as "connection", "installation", "fixation", etc. should all be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0246] In the description of the present invention, the descriptions of terms such as "one embodiment", "some embodiments", "specific embodiments", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In the present invention, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0247] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A control method for a water treatment device, characterized in that, it includes: Receiving a set value of the outlet water temperature; Obtaining the historical operation information of the water treatment device, wherein the historical operation information includes the collected values of the actual outlet water flow rate and the outlet water temperature; Inputting the actual outlet water flow rate and the collected value into a state observer to obtain a first estimated value of the outlet water temperature and a second estimated value of an unknown disturbance output by the state observer; Determining a control value of the outlet water flow rate according to the set value, the first estimated value and the second estimated value; Controlling the operation of the pump body of the water treatment device according to the control value; The determining the control value of the outlet water flow rate according to the set value, the first estimated value and the second estimated value includes: Obtaining the volume value of the heating barrel of the water treatment device and the target control parameter value of the state observer; Determining the deviation value between the set value and the first estimated value; Determining the product value of the deviation value and the target control parameter value; Taking the product of the difference between the product value and the second estimated value and the volume value as the control value.

2. The control method for a water treatment device according to claim 1, characterized in that, it further includes: Obtaining at least two candidate control parameter values; Determining the target control parameter value from the at least two candidate control parameter values according to the magnitude of the deviation value.

3. The control method for a water treatment device according to claim 2, characterized in that, each of the candidate control parameter values corresponds to a deviation interval, and the control method further includes: Determining the deviation interval corresponding to the deviation value; Determining the target control parameter value according to the corresponding relationship between the deviation interval and the candidate control parameter value.

4. The control method for a water treatment device according to claim 2, characterized in that, the deviation value is negatively correlated with the target control parameter value.

5. The control method for a water treatment device according to any one of claims 1 to 4, characterized in that, before obtaining the historical operation information of the water treatment device, it further includes: Obtaining the inlet water temperature value of the water treatment device; Based on the set value being less than or equal to the inlet water temperature value, controlling the operation of the pump body.

6. The control method for a water treatment device according to claim 2, characterized in that, controlling the operation of the pump body of the water treatment device according to the control value specifically includes: Determining the voltage duty cycle of the pump body according to the control quantity; Controlling the operation of the pump body according to the voltage duty cycle.

7. A control device for a water treatment device, characterized in that, it includes: A receiving unit for receiving a set value of the outlet water temperature; A first obtaining unit for obtaining the historical operation information of the water treatment device, wherein the historical operation information includes the collected values of the actual outlet water flow rate and the outlet water temperature; A second obtaining unit for inputting the actual outlet water flow rate and the collected value into a state observer to obtain a first estimated value of the outlet water temperature and a second estimated value of an unknown disturbance output by the state observer; A determining unit for determining a control value of the outlet water flow rate according to the set value, the first estimated value and the second estimated value; A control unit for controlling the operation of a pump body of the water treatment device according to the control value; The determining unit is configured to: obtain a volume value of a heating barrel of the water treatment device and a target control parameter value of the state observer; Determine a deviation value between the set value and the first estimated value; Determine a product value of the deviation value and the target control parameter value; Use the product of the difference between the product value and the second estimated value and the volume value as a control value.

8. A readable storage medium, Characterized in that Programs or instructions are stored on the readable storage medium, and when the programs or instructions are executed by a processor, the steps of the control method of the water treatment device according to any one of claims 1 to 6 are implemented.

9. A water treatment device, Characterized in that Comprising: A heating barrel; A pump body located on the water inlet pipeline of the heating barrel; The control device of the water treatment device according to claim 7; or The readable storage medium according to claim 8.

10. The water treatment device according to claim 9, Characterized in that The water treatment device includes any one of a water purifier, a water dispenser, and a water heater.

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