Control method and device of water heater, electronic equipment and readable storage medium

Abstract

The invention provides a control method and device of a water heater, electronic equipment and a readable storage medium. The method comprises the steps that the set water temperature, the current power, the current water inlet flow and the water inlet flow at the last moment are obtained; inputting the current power, the current input water flow and the water inlet flow at the previous moment into a feed-forward controller, and determining the power compensation amount or quitting the compensation mode; according to the set temperature and the power compensation amount, active-disturbance-rejection control processing is conducted on the water heater through a second-order nonlinear active-disturbance-rejection controller, and control power of the water heater is generated; a proportional integral parameter in the second-order nonlinear active disturbance rejection controller is determined according to the current water inlet flow; and the water heater is controlled according to the control power, and the water outlet temperature of the water heater is obtained. The proportional integral parameter in the second-order nonlinear active disturbance rejection controller is determined according to the current water inlet flow, and the quitable feed-forward module is a nonlinear compensation module, so that temperature fluctuation caused by water flow fluctuation can be converged more quickly.

Description

Technical Field

[0001] The present invention belongs to the technical field of smart home, and particularly relates to a control method, device, electronic device and readable storage medium for a water heater. Background Art

[0002] With the continuous development of electronic technology, the volume occupied by household water heaters is getting smaller and smaller, and the functions are getting more and more, but the control complexity is getting higher and higher. In order to save energy, gas water heaters generally adopt a heating structure with multiple sections of fire rows, and the water is heated differently by separately controlling the multiple sections of fire rows, so as to improve the heating efficiency of the water and save energy.

[0003] However, in the actual application process, when the input water flow fluctuates, it is easy to cause abnormal outlet water temperature, which greatly reduces the user experience. Summary of the Invention

[0004] Embodiments of the present invention provide a control method, device, electronic device and readable storage medium for a water heater, which can solve the problem of abnormal outlet water temperature when the input water flow fluctuates.

[0005] In a first aspect, the present application provides a control method for a water heater, the method comprising:

[0006] Obtain the set water temperature, the current power, the current water inlet flow rate and the water inlet flow rate at the previous moment;

[0007] Input the current power, the current water inlet flow rate and the water inlet flow rate at the previous moment into a feedforward controller to determine the power compensation amount or exit the compensation mode; the feedforward controller is a non-linear compensation module;

[0008] According to the set temperature and the power compensation amount, perform an auto-disturbance rejection control process on the water heater through a second-order non-linear auto-disturbance rejection controller to generate the control power of the water heater; the proportional-integral parameters in the second-order non-linear auto-disturbance rejection controller are determined according to the current water inlet flow rate;

[0009] Control the water heater according to the control power to obtain the outlet water temperature of the water heater.

[0010] Optionally, the inputting the current power, the current water inlet flow rate and the water inlet flow rate at the previous moment into a feedforward controller to obtain the power compensation amount or exit the compensation mode includes:

[0011] Determine the flow difference between the current water inlet flow rate and the water inlet flow rate at the previous moment through the feedforward controller;

[0012] When the flow difference is greater than a preset flow threshold, determine the power compensation amount according to the current power and the flow difference through the feedforward controller;

[0013] When the flow difference is less than or equal to the flow threshold, exit the compensation mode through the feedforward controller.

[0014] Optionally, when the flow difference is greater than a preset flow threshold, determining the power compensation amount according to the current power and the flow difference through the feedforward controller includes:

[0015] When the flow difference is greater than the flow threshold, determine the flow ratio of the flow difference to the inlet water flow at the previous moment through the feedforward controller;

[0016] Use the product of the current power, the flow ratio, and a preset feedforward coefficient as the power compensation amount through the feedforward controller.

[0017] Optionally, when the flow difference is less than or equal to the flow threshold, exiting the compensation mode through the feedforward controller includes:

[0018] When the flow difference is less than or equal to the flow threshold, set the power compensation amount to zero through the feedforward controller.

[0019] Optionally, the second-order nonlinear active disturbance rejection controller includes a differential tracker, a state error feedback module, and a nonlinear extended state observer. The differential tracker is connected to the nonlinear extended state observer through the state error feedback module. Using the second-order nonlinear active disturbance rejection controller to perform active disturbance rejection control processing on the water heater according to the set temperature and the power compensation amount to generate a control power includes:

[0020] Perform smooth transition calculation according to the set temperature through the differential tracker to generate a transition temperature;

[0021] Generate a total disturbance estimation amount through the nonlinear extended state observer;

[0022] Perform compensation calculation according to the transition temperature, the power compensation amount, and the total disturbance estimation amount through the state error feedback module to generate a control power.

[0023] Optionally, the total disturbance estimation amount includes a temperature estimation value and a disturbance estimation value. Using the state error feedback module to generate a control power according to the transition temperature, the power compensation amount, and the total disturbance estimation amount includes:

[0024] The state error feedback module performs compensation calculations based on the transition temperature, the power compensation amount, the temperature estimate, and the disturbance estimate to generate a control power.

[0025] Optionally, controlling the water heater according to the control power to obtain the outlet water temperature of the water heater includes:

[0026] Calculating the outlet water temperature of the water heater according to the control power through a pre-constructed physical model to obtain the outlet water temperature of the water heater.

[0027] Optionally, the method further includes:

[0028] Obtaining the inlet water temperature of the water heater;

[0029] Adjusting the valve opening of the water heater according to the current inlet water flow rate, the inlet water temperature, and the outlet water temperature of the water heater.

[0030] Optionally, the valve of the water heater includes a proportional valve and a solenoid valve. Adjusting the valve opening of the water heater according to the current inlet water flow rate, the inlet water temperature, and the outlet water temperature of the water heater includes:

[0031] Converting the control quantity corresponding to the control power into a secondary pressure;

[0032] Converting the secondary pressure into a pulse width modulation signal;

[0033] Controlling the proportional valve opening and the solenoid valve opening through the pulse width modulation signal.

[0034] In a second aspect, the present application provides a control device for a water heater. The device includes:

[0035] An acquisition module for acquiring a set water temperature, a current power, a current inlet water flow rate, and an inlet water flow rate at the previous moment;

[0036] A feedforward control module that inputs the current power, the current inlet water flow rate, and the inlet water flow rate at the previous moment into a feedforward controller to determine the power compensation amount or exit the compensation mode; the feedforward controller is a non-linear compensation module;

[0037] A power generation module for performing an active disturbance rejection control process on the water heater through a second-order non-linear active disturbance rejection controller according to the set temperature and the power compensation amount to generate the control power of the water heater; the proportional-integral parameters in the second-order non-linear active disturbance rejection controller are determined according to the current inlet water flow rate;

[0038] A temperature control module for controlling the water heater according to the control power to obtain the outlet water temperature of the water heater.

[0039] In a third aspect, the present application provides an electronic device, including: a processor, a memory, and a computer program stored on the memory and executable on the processor, where when the processor executes the program, the control method of the above water heater is implemented.

[0040] In a fourth aspect, the present application provides a readable storage medium, when the instructions in the readable storage medium are executed by a processor of an electronic device, enabling the electronic device to execute the control method of the above water heater.

[0041] In the embodiment of the present application, first, obtain the set water temperature, the current power, the current water inlet flow rate, and the water inlet flow rate at the previous moment. Second, input the current power, the current water inlet flow rate, and the water inlet flow rate at the previous moment into a feedforward controller to obtain a power compensation amount or exit the compensation mode, where the feedforward controller is a non-linear compensation module. Third, according to the set temperature and the power compensation amount, perform an active disturbance rejection control process on the water heater through a second-order non-linear active disturbance rejection controller to generate the control power of the water heater, where the proportional-integral parameters in the second-order non-linear active disturbance rejection controller are determined according to the current water inlet flow rate. Finally, control the water heater according to the control power to obtain the outlet water temperature of the water heater. Through the above technical solution, since the proportional-integral parameters in the second-order non-linear active disturbance rejection controller are determined according to the current water inlet flow rate, the temperature fluctuation caused by the water flow rate fluctuation will converge faster, reducing overshoot and adjustment time. And, the withdrawable feedforward module is a non-linear compensation module, which has the advantages of non-linear compensation compared with linear compensation, with faster speed and better effect. Therefore, combining the variable-parameter second-order non-linear active disturbance rejection controller and the non-linear feedforward controller can greatly improve the response efficiency and accuracy of control, and solve the problem of abnormal outlet water temperature caused by the lag of the control power when the input water flow fluctuates. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0043] Figure 1 is a step flowchart of a control method for a water heater provided by an embodiment of the present application;

[0044] Figure 2 is a schematic structural diagram of a second-order non-linear active disturbance rejection controller and a feedforward controller provided by an embodiment of the present application;

[0045] Figure 3 It is a specific step flowchart of a control method for a water heater provided by an embodiment of the present application;

[0046] Figure 4 It is a schematic diagram showing the change of the outlet water temperature of a water heater with the inlet water flow provided by an embodiment of the present application;

[0047] Figure 5 A schematic diagram of the overall architecture of a water heater provided by an embodiment of the present application;

[0048] Figure 6 It is a structural diagram of a control device for a water heater provided by an embodiment of the present application;

[0049] Figure 7 It is a structural diagram of an electronic device provided by an embodiment of the present application;

[0050] Figure 8 It is a structural diagram of another electronic device provided by an embodiment of the present application. Detailed implementation manners

[0051] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. According to the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present application.

[0052] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of the same type, and the number of objects is not limited. For example, the first object can be one or multiple. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally indicates an "or" relationship between the associated objects before and after.

[0053] In the description of the present disclosure, unless otherwise specified, "a plurality of" means two or more, and other quantifiers are similar; "at least one", "one or more" or similar expressions refer to any combination of these items, including any combination of a single item or plural items. For example, at least one a can represent any number of a; for another example, one or more of a, b, and c can represent: a, b, c, a - b, a - c, b - c, or a - b - c, where a, b, and c can be single or multiple; "and / or" is a relationship describing associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. Here, A and B can be singular or plural. The character " / " indicates that the associated objects before and after are in an "or" relationship.

[0054] In the embodiments of the present disclosure, although operations or steps are described in a specific order in the drawings, it should not be understood that these operations or steps are required to be performed in the specific order shown or in a serial order, nor are all the shown operations or steps required to be performed to obtain the desired result. In the embodiments of the present disclosure, these operations or steps can be performed serially; they can also be performed in parallel; or a part of these operations or steps can be performed.

[0055] Currently, in order to ensure the combustion efficiency of gas and avoid incomplete combustion of gas to produce carbon monoxide with different concentrations and cause environmental pollution, gas water heaters usually design the burner plates as a three - stage type, and switch the opening and closing of the sectional valve according to different working conditions to control the combustion area of the burner plates. When the burner is switched, there will be a power overlap area, and the change of the power overlap area may lead to repeated switching of the burner, and then cause the water temperature to rise instantaneously, which brings trouble to users; at the same time, the different controls of multiple - stage burner plates greatly increase the control complexity of the water heater, and also bring control difficulties and technical troubles to technicians.

[0056] During the actual use process, when a user needs to use hot water, the household gas water heater is turned on to obtain hot water. However, since the current time is in the peak water - using period, the water flow rate fluctuates, that is, the input water flow rate of the gas water heater fluctuates at this time. Since this gas water heater is a multi - stage burner water heater, for example, in the embodiments of the present invention, this gas water heater is a gas water heater with a row of burner plates. During the process of heating the input water flow, due to the fluctuation of the water flow rate, the problem of frequent switching of the burner plates occurs, and thus the problem of instantaneous increase in the water temperature during heating occurs, which brings trouble to the actual use of users.

[0057] To solve the above technical problems, the present application provides a control method, device, electronic device and readable storage medium for a water heater. By compensating the current power of the water heater through a feedforward controller, the control efficiency can be accelerated, and thus the timeliness of temperature adjustment can be improved.

[0058] The following details the control method for the water heater provided in the embodiments of the present application.

[0059] Figure 1 is a flowchart of the steps of a control method for a water heater provided in the embodiments of the present application. As Figure 1 shown, the method may include:

[0060] Step 101, obtain the set water temperature, the current water inlet flow rate, and the water inlet flow rate at the previous moment.

[0061] In the embodiments of the present application, the set temperature refers to the outlet water temperature of the water heater to be set by the user, and this set temperature is set by the user according to the actual situation.

[0062] In the embodiments of the present application, the current water inlet flow rate and the water inlet flow rate at the previous moment can be obtained by a flow sensor preset in the water heater. Among them, the previous moment can be the previous sampling moment.

[0063] In some embodiments, before step 101, the control method for the above water heater may further include: obtaining the water inlet flow rate of the water heater in real time through a flow sensor, and periodically sampling the water inlet flow rate of the water heater through an analog-to-digital converter (AD module). Among them, the sampling period of the AD module can be set according to actual needs.

[0064] Exemplarily, the sampling period of the water inlet flow rate can be 50 milliseconds (ms), the AD module can be changed to a high-frequency crystal oscillator, and the baud rate can be increased in the software.

[0065] Step 102, input the current power, the current water inlet flow rate, and the water inlet flow rate at the previous moment into the feedforward controller, and determine the power compensation amount or exit the compensation mode.

[0066] In the embodiments of the present application, the feedforward controller is a non-linear compensation module, and the feedforward controller can be a controller for obtaining a pre-feedback signal.

[0067] In the embodiments of the present application, the power compensation amount can be a feedforward compensation coefficient for compensating the control power of the water heater, or the power compensation amount can also be a compensation power value for adjusting the control power of the water heater.

[0068] In the embodiments of the present application, the compensation mode refers to periodically obtaining the current water inlet flow rate and calculating the power compensation amount. Exiting the compensation mode can be to stop calculating the power compensation amount or set the power compensation amount to zero.

[0069] It can be understood that since the non - linear error observer in the second - order non - linear active disturbance rejection control is in the feedback system of the control loop and has a certain lag, it causes fluctuations in the water flow rate, and there is a certain lag in temperature regulation. That is to say, in the case of water flow rate fluctuations, there is a certain lag in temperature regulation. Therefore, by compensating the current power of the water heater through a feed - forward controller in the present application, the control efficiency can be accelerated, and thus the timeliness of temperature regulation can be improved.

[0070] In some embodiments, step 102 may include:

[0071] Sub - step 1021: When the current water inlet flow rate is equal to the water inlet flow rate at the previous moment, set the value of the power compensation amount to zero.

[0072] Sub - step 1022: When the current water flow rate is not equal to the water inlet flow rate at the previous moment, determine the power compensation amount according to the current power, the current water inlet flow rate, and the water inlet flow rate at the previous moment.

[0073] In this way, when the water flow rate is stable, the feed - forward controller can set the power compensation amount to zero. That is to say, the feed - forward controller exits the compensation mode, and in this way, the power consumption of the water heater can be reduced.

[0074] Step 103: According to the set temperature and the power compensation amount, perform active disturbance rejection control processing on the water heater through a second - order non - linear active disturbance rejection controller to generate the control power of the water heater.

[0075] In the embodiments of the present application, the proportional - integral parameters in the second - order non - linear active disturbance rejection controller are determined according to the current water inlet flow rate.

[0076] In the embodiments of the present application, the second - order non - linear active disturbance rejection controller includes a differential tracker, a state error feedback module, and an extended state observer. Among them, the state error feedback module can also be referred to as a "non - linear state error feedback controller".

[0077] It should be noted that the second-order nonlinear active disturbance rejection controller (NLADRC) is a new control method improved on the basis of the Proportion Integral Differential (PID) control algorithm. It has the structural characteristics of not depending on the control object model and not distinguishing between internal and external disturbances of the system. The commonly used active disturbance rejection controller mainly consists of three parts: a Tracking Differentiator (TD), an Extended State Observer (ESO), and a Nonlinear State Error Feedback (NLSEF) controller. The role of the tracking differentiator is to extract the required signals according to the input characteristics of the controlled object. As the core component of the active disturbance rejection control, the extended state observer can, on the one hand, track important state variables in the system to facilitate real-time understanding of the system state; on the other hand, it can also compensate for the overall action of internal and external disturbances in the system model in a feedback form in a timely manner, which helps to improve the robustness of the system. The nonlinear state error feedback controller is a non-linear combination method. The input is the error between the state variable output by the TD and the state estimation value of the ESO, and the output combines the total disturbance compensation value of the ESO to obtain the control quantity of the controller.

[0078] In the embodiments of the present application, the proportional integral parameters include a proportional parameter (Proportional, KP) and an integral parameter (Integral, KI). The KP and KI in the second-order nonlinear active disturbance rejection controller are determined according to the current water inlet flow rate. Among them, KP represents the proportional action, the linear relationship between the controller output and the error. The larger KP is, the faster the output response is, but it is also easy to cause oscillation and instability. KI represents the integral action, the relationship between the controller output and the integral of the error. The larger KI is, the stronger the integral response of the output to the error is, but it is also easy to cause overshoot and oscillation of the system.

[0079] Optionally, KP and KI can be the parameters in the nonlinear state error feedback controller of the second-order nonlinear active disturbance rejection controller.

[0080] It can be understood that due to the heating power limitation of the water heater, when the water inlet flow rate is small, continuous cut-off is required to heat to a higher temperature, and the cut-off will also cause temperature overshoot. Therefore, the proportional parameter and the integral parameter in the nonlinear state error feedback controller in the present application are determined according to the current water flow rate. That is to say, there is a corresponding relationship between the proportional parameter and the integral parameter and the water inlet flow rate, so that the nonlinear state error feedback module can achieve adaptive changes according to the current water inlet flow rate.

[0081] In some embodiments, before step 103, the control of the above water heater may further include: performing linearization processing on the KPKI parameter with the water inlet flow rate as the independent variable to obtain the corresponding relationship between the KPKI parameter and the water inlet flow rate; determining the proportional-integral parameter corresponding to the current water inlet flow rate according to the corresponding relationship; and configuring the non-linear state error feedback module with the proportional-integral parameter.

[0082] Exemplarily, Figure 2 FIG. is a schematic structural diagram of a second-order non-linear active disturbance rejection controller and a feed-forward controller provided by an embodiment of the present application. Refer to Figure 2 , V represents the target tracking signal, V1 represents the processed target tracking signal; V2 represents the differential of the processed target tracking signal, Z1 represents the filtered estimated value of the output temperature, Z2 represents the estimated value of the total disturbance, U1 represents the power compensation amount calculated by the feed-forward controller, U1 represents the feedback control amount calculated by the non-linear state error feedback controller, U is the total input of the feedback control amount, and e is the feedback input. Among them, the compensation coefficient can be b0, and b0 is a key gain parameter in the active disturbance rejection controller (ADRC) algorithm, which is an estimate of the input gain of the controlled object and is used to describe the response degree of the controlled object to the input signal. In the embodiments of the present application, the compensation coefficient can be set in advance according to a large number of experiments.

[0083] Step 104: Control the water heater according to the control power to obtain the outlet water temperature of the water heater.

[0084] In the embodiments of the present application, the calculated control power value is output to the heating device of the gas water heater to adjust the operating state of the water heater and achieve precise control of the outlet water temperature. Among them, the heating device may include actuators such as a gas valve and a water pump.

[0085] In some embodiments, step 104 may include: determining the operating parameters of the heating device of the water heater according to the control power, and controlling the heating device according to the operating parameters to obtain the outlet water temperature of the water heater.

[0086] In other embodiments, step 104 may further include: calculating the outlet water temperature of the water heater according to the control power through a pre-constructed physical model to obtain the outlet water temperature.

[0087] Exemplarily, a physical model of a gas water heater can be constructed. According to this physical model, the outlet water temperature can be calculated based on the control power to obtain the outlet water temperature. Then, taking the water flow rate, the inlet water temperature, and the power as input quantities, and the temperature rise as the output quantity, the parameter identification toolbox of MATLAB (a mathematical software) is used to estimate the state space equation model based on the input and output quantities to obtain the physical model of the gas water heater.

[0088] In summary, for the control method of the water heater in the embodiments of the present application, first, the set water temperature, the current power, the current water inlet flow rate, and the water inlet flow rate at the previous moment are obtained. Secondly, the current power, the current water inlet flow rate, and the water inlet flow rate at the previous moment are input into the feedforward controller to obtain the power compensation amount. Thirdly, according to the set temperature and the power compensation amount, the water heater is subjected to an active disturbance rejection control process through a second-order nonlinear active disturbance rejection controller to generate the control power of the water heater. Finally, the water heater is controlled according to the control power to obtain the outlet water temperature of the water heater. Through the above technical solutions, since the proportional-integral parameters in the second-order nonlinear active disturbance rejection controller are determined according to the current water inlet flow rate, the temperature fluctuations caused by water flow rate fluctuations will converge faster, reducing overshoot and adjustment time. And, the withdrawable feedforward module is a nonlinear compensation module, which has the advantages of nonlinear compensation, faster speed and better effect compared with linear compensation. Therefore, combining the second-order nonlinear active disturbance rejection controller with variable parameters and the nonlinear feedforward controller can greatly improve the response efficiency and accuracy of the control, and solve the problem of abnormal outlet water temperature caused by the lag of the control power when the input water flow fluctuates.

[0089] Figure 3 It is a specific step flowchart of a control method for a water heater provided by an embodiment of the present application. Refer to Figure 3 and the method may include:

[0090] Step 201, obtain the set water temperature and the current water inlet flow rate.

[0091] The method of this step has been described in the foregoing step 101 and will not be elaborated here.

[0092] Step 202, input the current power, the current water inlet flow rate, and the water inlet flow rate at the previous moment into the feedforward controller to determine the power compensation amount or exit the compensation mode.

[0093] The method of this step has been described in the foregoing step 102 and will not be elaborated here.

[0094] In some embodiments, step 202 may include:

[0095] Sub-step 2021, determine the flow difference between the current water inlet flow rate and the water inlet flow rate at the previous moment through the feedforward controller.

[0096] Sub-step 2022: When the flow difference is greater than a preset flow threshold, determine the power compensation amount according to the current power and the flow difference through a feed-forward controller;

[0097] Sub-step 2023: When the flow difference is less than or equal to the flow threshold, exit the compensation mode through the feed-forward controller.

[0098] In the embodiment of the present application, the preset flow difference threshold can be 0, or it can be a relatively small flow value, which can be set according to actual needs.

[0099] In some embodiments, sub-step 2022 may include:

[0100] Sub-step A1: When the flow difference is greater than a preset flow threshold, determine the flow ratio of the flow difference to the inlet water flow at the previous moment through the feed-forward controller.

[0101] Sub-step A2: Multiply the current power, the flow ratio, and a preset feed-forward coefficient through the feed-forward controller as the power compensation amount.

[0102] In the embodiment of the present application, the preset flow threshold can be 0, or it can be set according to actual needs.

[0103] Exemplarily, in sub-step A1 and sub-step A2, the following formula can be used to calculate the power compensation amount.

[0104]

[0105] In the above formula, P 补偿 represents the power compensation amount, K represents the proportional coefficient of the optimal feed-forward amount determined through experiments, P 0 represents the current power, L 1 represents the current inlet water flow, L 0 represents the inlet water flow at the previous moment.

[0106] In some embodiments, sub-step 2023 may include:

[0107] Sub-step B1: When the flow difference is less than or equal to the flow threshold, set the power compensation amount to zero through the feed-forward controller.

[0108] It can be understood that the feed-forward amount value is a change amount value. When the water heater starts to operate in the initial stage, the inlet water flow changes greatly, and the power compensation amount calculated by the feed-forward control is also large; when the flow difference is zero, L 1 -L 0 is equal to 0. Therefore, the power compensation amount is set to zero through the feed-forward controller.

[0109] It can be understood that by compensating the current power of the water heater through the feedforward controller, the efficiency of control can be accelerated. When the inlet water flow fluctuates, since the feedforward quantity (power compensation quantity) output by the feedforward controller changes the power in advance, the final temperature fluctuation can be minimized. Exemplarily, Figure 4 is a schematic diagram showing the change of the outlet water temperature of the water heater with the inlet water flow provided by an embodiment of the present application. Refer to Figure 4 , the inlet water flow increases sequentially from left to right. In the case of a relatively small inlet water flow, the temperature fluctuation is relatively large before improvement, and the temperature change is smoother after improvement; in the case of a relatively large and fluctuating inlet water flow, the temperature fluctuates greatly up and down before improvement, and changes slightly after improvement. It can be seen that for each water flow rate, the method of the present application significantly improves the overshoot of the temperature rise under each water flow rate, and will not increase the overshoot due to load shedding or small flow.

[0110] In some other embodiments, the feedforward controller can also be applied to the wind speed control or angle control of the water heater. By calculating the wind speed compensation quantity or angle compensation quantity through the feedforward controller, the purpose of smoothing the wind speed change curve or angle change curve can be achieved.

[0111] Step 203: Perform a smooth transition calculation according to the set temperature through a differential tracker to generate a transition temperature.

[0112] In the embodiment of the present application, the differential tracker can smooth the set temperature signal. This helps to reduce the overshoot of the system to temperature changes and improve the dynamic response performance of the system. The differential tracker is designed as a link with a filtering function, which can eliminate the noise in the input signal and generate a smooth tracking signal. In the embodiment of the present application, a smooth transition calculation is performed according to the set temperature through the differential tracker to generate a transition temperature, and this transition temperature is used as the input of the non-linear state error feedback compensator.

[0113] Step 204: Generate a total disturbance estimation quantity through a non-linear extended state observer.

[0114] In the embodiment of the present application, the total disturbance estimation quantity includes a temperature estimation value and a disturbance estimation value. Among them, the temperature estimation value can be a temperature filtered estimation value.

[0115] In the embodiment of the present application, the extended state observer estimates the state variables and total disturbance of the system in real time according to the input and output data of the gas water heater (such as input power, outlet water temperature, etc.), and generates a temperature estimation value and a disturbance estimation value.

[0116] In some embodiments, step 204 may include: generating a temperature estimation value and a disturbance estimation value through a non-linear extended state observer.

[0117] Exemplarily, the discretization formula of the non-linear extended state observer is as follows:

[0118] e(k) = z 1 (k) - y(k)

[0119] z 1 (k + 1) = z 1 (k) + h(z 2 (k) - β 01 fal(e, α 1 , δ) + bu(k))

[0120] z 2 (k + 1) = z 2 (k) - β 02 fal(e, α 2 , δ)

[0121] Wherein, fal(e, α, δ) represents a non-linear error tracking function, and its formula is:

[0122]

[0123] In the above formula, e(k) is the temperature difference of the system, y(k) is the outlet water temperature, z 1 (k) is the temperature filtering estimated value, z 2 (k) is the disturbance estimated value, β 01 , β 02 are the observer gains, α, α 1 , α 2 and δ are the parameters of the non-linear error tracking function, u(k) represents the control input value at time point k, b is the system model coefficient, u(k) is the controller output value, h is the sampling step, and b is the system model coefficient. bu(k) represents the influence of the control input value u(k) on the system state through the system model coefficient b at time point k, and this system model coefficient refers to the sampling step.

[0124] Step 205, perform compensation calculation through the state error feedback module according to the transition temperature, power compensation amount, and total disturbance estimated amount to generate the control power.

[0125] In the embodiment of the present application, the state error feedback module calculates the control input according to the output of the differential tracker (i.e., the smoothed set temperature) and the estimation results of the extended state observer (i.e., the temperature filtering estimated value and the disturbance estimated value) to compensate for the non-linear characteristics inside the system and external disturbances. A non-linear combination method is adopted to improve the control performance and robustness of the system. By adjusting the control input in real time, the system output (i.e., the outlet water temperature) can quickly and accurately track the set temperature.

[0126] In some embodiments, step 205 may include:

[0127] Sub-step 2051: Perform compensation calculation by the state error feedback module according to the transition temperature, power compensation amount, temperature estimation value, and disturbance estimation value to generate the control power.

[0128] Optionally, sub-step 2051 may include: calculating the error between the transition temperature and the temperature estimation value to generate an error signal; calculating the difference between the input power and the disturbance estimation value to generate a power error value; multiplying the reciprocal of the preset system model coefficient by the power error value to obtain a power estimation value; performing compensation calculation on the error signal and the power estimation value through the temperature estimation value and the disturbance estimation value to generate the control power.

[0129] Step 206: Control the water heater according to the control power through a pre-constructed physical model to obtain the outlet water temperature of the water heater.

[0130] In the embodiments of the present application, the calculated control power value is output to actuators such as the gas valve and water pump of the gas water heater to adjust the operating state of the water heater and achieve precise control of the outlet water temperature.

[0131] Exemplarily, a physical model of the gas water heater can be constructed. According to this physical model, the outlet water temperature is calculated based on the control power to obtain the outlet water temperature. Then, taking the water flow rate, inlet water temperature, and power as input quantities and the temperature rise as the output quantity, the state space equation model is estimated using the parameter identification toolbox of MATLAB (a mathematical software) according to the input and output quantities to obtain the physical model of the gas water heater.

[0132] In some embodiments, the above control method of the water heater further includes:

[0133] Sub-step S1: Obtain the inlet water temperature of the water heater.

[0134] Sub-step S2: Adjust the valve opening of the water heater according to the current inlet water flow rate, inlet water temperature, and outlet water temperature of the water heater.

[0135] In the embodiments of the present application, the valves of the water heater include a proportional valve and a solenoid valve.

[0136] In some embodiments, sub-step S2 includes:

[0137] Sub-step S21: Convert the control quantity corresponding to the control power into a secondary pressure;

[0138] Sub-step S22: Convert the secondary pressure into a pulse width modulation signal;

[0139] Sub-step S23: Control the proportional valve opening and solenoid valve opening through the pulse width modulation signal.

[0140] It can be understood that the purpose of adjusting the secondary pressure in sub-step S21 is to adjust the mixing ratio of gas and air. The primary pressure refers to the pressure from the gas pipeline network to before the gas valve of the water heater; the secondary pressure refers to the working pressure from the gas valve to the combustion chamber. Adjusting the secondary pressure to an appropriate value can adjust the gas burner of the water heater to the best working state and prevent incomplete combustion, deflagration or failure to ignite in the combustion chamber.

[0141] Optionally, in sub-steps S21 to S23, through the actual power limiting module of the code, the Pulse Width Modulation (PWM) conversion module, the control proportional valve and the solenoid valve, the heating power is input into the water heater system.

[0142] It can be understood that. Since there will also be errors in the opening of the proportional valve under the same driving parameters, it is necessary to eliminate the proportional valve error. It is necessary to eliminate the error through the relationship between the heat load, the secondary pressure, and the PWM value of the proportional valve, so as to obtain a better control effect.

[0143] In summary, for the control method of the water heater in the embodiment of the present application, on the one hand, according to the nonlinear auto-disturbance rejection algorithm of the withdrawable variable-parameter feedforward compensation gas water heater, the current power of the water heater is compensated by the feedforward controller, and the feedforward compensation is withdrawn when the water flow rate and temperature are reached. This can not only improve the control efficiency, but also reduce the power consumption of the water heater, achieving the purpose of saving energy. On the other hand, since the proportional parameter and the integral parameter in the nonlinear state error feedback controller are determined according to the current water flow rate, that is to say, there is a corresponding relationship between the proportional parameter and the integral parameter and the incoming water flow rate, the nonlinear state error feedback module can achieve adaptive changes according to the current incoming water flow rate.

[0144] Figure 5 A schematic diagram of the overall architecture of a water heater provided by an embodiment of the present application is shown in Figure 5As shown, the state error feedback module calculates the control input based on the output of the differential tracker (i.e., the smoothed set temperature) and the estimation results of the extended state observer (i.e., the temperature filtered estimate and the disturbance estimate) to compensate for the internal nonlinear characteristics and external disturbances of the system. A nonlinear combination method is adopted to improve the control performance and robustness of the system. By adjusting the control input in real time, the system output (i.e., the outlet water temperature) can quickly and accurately track the set temperature. Through the actual power limiting module of the code, the Pulse Width Modulation (PWM) conversion module controls the proportional valve and the solenoid valve, and inputs the heating power into the heating device of the water heater system. In this way, the constant temperature control of the water heater is realized, and the water heater will not cause the outlet water temperature to be hot and cold due to the fluctuation of the inlet water flow, thus giving the user a more accurate water temperature and improving the user experience.

[0145] Figure 6 FIG. is a structural diagram of a control device for a water heater provided by an embodiment of the present application. The control device 600 of the water heater may include:

[0146] An acquisition module 601, configured to acquire the set water temperature, the current power, the current inlet water flow, and the inlet water flow at the previous moment;

[0147] A feedforward compensation module 602, configured to input the current power, the current inlet water flow, and the inlet water flow at the previous moment into a feedforward controller to determine the power compensation amount or exit the compensation mode; the feedforward controller is a nonlinear compensation module;

[0148] A processing module 603, configured to perform an active disturbance rejection control process on the water heater through a second-order nonlinear active disturbance rejection controller according to the set temperature and the power compensation amount, and generate the control power of the water heater; the proportional-integral parameters in the second-order nonlinear active disturbance rejection controller are determined according to the current inlet water flow;

[0149] A temperature control module 604, configured to control the water heater according to the control power to obtain the outlet water temperature of the water heater.

[0150] Optionally, the feedforward compensation module 602 includes:

[0151] A first determination sub-module, configured to determine the flow difference between the current inlet water flow and the inlet water flow at the previous moment through a feedforward controller;

[0152] A second determination sub-module, configured to determine the power compensation amount through a feedforward controller according to the current power and the flow difference when the flow difference is greater than a preset flow threshold;

[0153] A first control sub-module, configured to exit the compensation mode through a feedforward controller when the flow difference is less than or equal to the flow threshold.

[0154] Optionally, the second determination sub-module includes:

[0155] The first determination unit is configured to, when the flow difference is greater than a preset flow threshold, determine a flow ratio of the flow difference to the water inlet flow at the previous moment through a feedforward controller;

[0156] The second determination unit is configured to use the feedforward controller to take the product of the current power, the flow ratio, and a preset feedforward coefficient as the power compensation amount.

[0157] Optionally, the first control sub-module includes:

[0158] The control unit is configured to, when the flow difference is less than or equal to the flow threshold, set the power compensation amount to zero through the feedforward controller.

[0159] Optionally, the second-order nonlinear active disturbance rejection controller includes a differential tracker, a state error feedback module, and a nonlinear extended state observer. The differential tracker is connected to the nonlinear extended state observer through the state error feedback module. The processing module 603 includes:

[0160] The first sub-generation module is configured to perform a smooth transition calculation based on a set temperature through the differential tracker to generate a transition temperature;

[0161] The second sub-generation module is configured to generate a total disturbance estimation amount through the nonlinear extended state observer;

[0162] The third sub-generation module is configured to perform a compensation calculation based on the transition temperature, the power compensation amount, and the total disturbance estimation amount through the state error feedback module to generate a control power.

[0163] Optionally, the total disturbance estimation amount includes a temperature estimation value and a disturbance estimation value. The third sub-generation module includes:

[0164] The generation unit is configured to perform a compensation calculation based on the transition temperature, the power compensation amount, the temperature estimation value, and the disturbance estimation value through the state error feedback module to generate a control power.

[0165] Optionally, the control device 600 of the water heater further includes:

[0166] The temperature calculation module is configured to calculate the outlet water temperature of the water heater based on the control power through a pre-constructed physical model to obtain the outlet water temperature of the water heater.

[0167] Optionally, the control device 600 of the water heater further includes:

[0168] The temperature acquisition module is configured to acquire the inlet water temperature of the water heater;

[0169] A valve adjustment module, configured to adjust the valve opening degree of a water heater according to the current water inlet flow rate, water inlet temperature, and the water outlet temperature of the water heater.

[0170] Optionally, the valve adjustment module includes:

[0171] A first conversion sub-module, configured to convert the control quantity corresponding to the control power into a secondary voltage;

[0172] A second conversion sub-module, configured to convert the secondary voltage into a pulse width modulation signal;

[0173] A control sub-module, configured to control the opening degrees of a proportional valve and a solenoid valve through the pulse width modulation signal.

[0174] For the apparatus embodiment, since it is basically similar to the method embodiment, the description is relatively simple. For related parts, refer to the partial description of the method embodiment.

[0175] This application also provides an electronic device. Refer to Figure 7 , the electronic device 700 may include one or more of the following components: a processing component 702, a memory 704, a power supply component 706, a multimedia component 708, an audio component 710, an input / output (I / O) interface 712, a sensor component 714, and a communication component 716.

[0176] The processing component 702 generally controls the overall operation of the electronic device 700, such as operations associated with display, telephone call, data communication, camera operation, and recording operation. The processing component 702 may include one or more processors 720 to execute instructions to complete all or part of the steps of the above method. In addition, the processing component 702 may include one or more modules to facilitate the interaction between the processing component 702 and other components. For example, the processing component 702 may include a multimedia module to facilitate the interaction between the multimedia component 708 and the processing component 702.

[0177] The memory 704 is used to store various types of data to support the operation of the electronic device 700. Examples of these data include instructions for any application or method operating on the electronic device 700, contact data, phone book data, messages, pictures, multimedia, etc. The memory 704 may be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, a magnetic disk, or an optical disc.

[0178] The power supply component 706 provides power for various components of the electronic device 700. The power supply component 706 may include a power management system, one or more power supplies, and other components associated with generating, managing, and distributing power for the electronic device 700.

[0179] The multimedia component 708 includes an interface that provides an output interface between the electronic device 700 and the user. In some embodiments, the interface may include a liquid crystal display (LCD) and a touch panel (TP). If the interface includes a touch panel, the interface can be implemented as a touch screen to receive input signals from the user. The touch panel includes one or more touch sensors to sense touches, swipes, and gestures on the touch panel. The touch sensors can not only sense the boundaries of touch or swipe actions, but also detect the duration and pressure associated with the touch or swipe operations. In some embodiments, the multimedia component 708 includes a front camera and / or a rear camera. When the electronic device 700 is in an operating mode, such as a shooting mode or a multimedia mode, the front camera and / or the rear camera can receive external multimedia data. Each of the front camera and the rear camera can be a fixed optical lens system or have a focal length and optical zoom capabilities.

[0180] The audio component 710 is used to output and / or input audio signals. For example, the audio component 710 includes a microphone (MIC) that is used to receive external audio signals when the electronic device 700 is in an operating mode, such as a call mode, a recording mode, and a voice recognition mode. The received audio signals can be further stored in the memory 704 or transmitted via the communication component 716. In some embodiments, the audio component 710 further includes a speaker for outputting audio signals.

[0181] The input / output (I / O) interface 712 provides an interface between the processing component 702 and a peripheral interface module, and the peripheral interface module can be a keyboard, a click wheel, buttons, etc. These buttons can include, but are not limited to: a home button, a volume button, a power-on button, and a lock button.

[0182] The sensor assembly 714 includes one or more sensors for providing a status assessment of various aspects of the electronic device 700. For example, the sensor assembly 714 can detect the on / off state of the electronic device 700, the relative positioning of components, such as the display and keypad of the electronic device 700. The sensor assembly 714 can also detect a change in the position of the electronic device 700 or a component of the electronic device 700, the presence or absence of user contact with the electronic device 700, the orientation or acceleration / deceleration of the electronic device 700, and a change in the temperature of the electronic device 700. The sensor assembly 714 can include a proximity sensor configured to detect the presence of nearby objects without any physical contact. The sensor assembly 714 can also include a light sensor, such as a CMOS or CCD image sensor, for use in imaging applications. In some embodiments, the sensor assembly 714 can also include an acceleration sensor, a gyroscope sensor, a magnetic sensor, a pressure sensor, or a temperature sensor.

[0183] The communication component 716 is used to facilitate communication between the electronic device 700 and other devices in a wired or wireless manner. The electronic device 700 can access a wireless network according to communication standards, such as WiFi, a carrier network (such as 2G, 3G, 4G, or 5G), or a combination thereof. In an exemplary embodiment, the communication component 716 receives a broadcast signal or broadcast-related information from an external broadcast management system via a broadcast channel. In an exemplary embodiment, the communication component 716 further includes a near field communication (NFC) module to facilitate short-range communication. For example, the NFC module can be implemented according to radio frequency identification (RFID) technology, infrared data association (IrDA) technology, ultra-wideband (UWB) technology, Bluetooth (BT) technology, and other technologies.

[0184] In an exemplary embodiment, the electronic device 700 can be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components for implementing a control method of a water heater provided in the embodiments of the present application.

[0185] In an exemplary embodiment, a non-transitory computer-readable storage medium including instructions is also provided, such as a memory 704 including instructions, and the above instructions can be executed by a processor 720 of the electronic device 700 to complete the above method. For example, the non-transitory storage medium can be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, and an optical data storage device, etc.

[0186] Figure 8It is a block diagram of an electronic device 800 according to another embodiment of the present invention. For example, the electronic device 800 may be provided as a server. Referring to Figure 8 , the electronic device 800 includes a processing component 822, which further includes one or more processors, and memory resources represented by a memory 832 for storing instructions executable by the processing component 822, such as application programs. The application programs stored in the memory 832 may include one or more modules each corresponding to a set of instructions. In addition, the processing component 822 is configured to execute instructions to perform a control method of a water heater provided in an embodiment of the present application.

[0187] The electronic device 800 may further include a power supply component 826 configured to perform power management of the electronic device 800, a wired or wireless network interface 850 configured to connect the electronic device 800 to a network, and an input / output (I / O) interface 858. The electronic device 800 may operate according to an operating system stored in the memory 832, such as WindowsServerTM, Mac OS XTM, UnixTM, LinuxTM, FreeBSDTM or the like.

[0188] In an embodiment of the present application, the memory 832 can be used to store software programs and various data. The memory 832 mainly includes a first storage area for storing programs or instructions and a second storage area for storing data. Among them, the first storage area can store an operating system, applications or instructions required for at least one function (such as a sound playback function, an image playback function, etc.). In addition, the memory 832 can include volatile memory or non-volatile memory, or the memory 832 can include both volatile and non-volatile memory. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), a static random access memory (SRAM), a dynamic random access memory (DRAM), a synchronous dynamic random access memory (SDRAM), a double data rate synchronous dynamic random access memory (DDR SDRAM), an enhanced synchronous dynamic random access memory (ESDRAM), a synch link dynamic random access memory (SLDRAM), and a direct rambus random access memory (DRRAM). The memory 832 in the embodiment of the present application includes, but is not limited to, these and any other suitable types of memory.

[0189] The processor may include one or more processing units; optionally, the processor integrates an application processor and a modem processor. Among them, the application processor mainly processes operations related to the operating system, user interface, and applications, etc., and the modem processor mainly processes wireless communication signals, such as a baseband processor. It can be understood that the above modem processor may not be integrated into the processor.

[0190] The present application also provides a readable storage medium. When the instructions in the readable storage medium are executed by the processor of the electronic device, the electronic device can execute the control method of the water heater in the foregoing embodiment.

[0191] The embodiment of the present application also provides a computer program product. The program product is stored in a storage medium and is executed by at least one processor to implement each process of the control method embodiment of the water heater as described above, and can achieve the same technical effects. To avoid repetition, it will not be elaborated here.

[0192] It should be noted that all kinds of information and data obtained in the embodiments of the present application are obtained under the authorization of the information / data holder. All actions of obtaining signals, information, or data in the present application are carried out on the premise of complying with the corresponding data protection regulations and policies of the country where it is located and obtaining the authorization given by the owner of the corresponding device.

[0193] The algorithms and displays provided herein are not inherently related to any particular computer, virtual system, or other device. Various general-purpose systems can also be used in conjunction with the teachings provided herein. The structure required to construct such systems will be apparent from the above description. In addition, the present application is not directed to any particular programming language. It should be understood that the content of the present application described herein can be implemented using various programming languages, and the description of the specific language above is to disclose the best mode of the present application.

[0194] In the specification provided herein, a large number of specific details are set forth. However, it can be understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures, and technologies have not been shown in detail so as not to obscure the understanding of this specification.

[0195] Similarly, it should be understood that, in order to streamline the present application and assist in understanding one or more of the various inventive aspects, in the above description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the disclosed method should not be construed as reflecting an intention that the claimed subject matter of the present application requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, the inventive aspects lie in less than all of the features of the single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate embodiment of the present application.

[0196] Those skilled in the art can understand that the modules in the devices in the embodiments can be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments can be combined into one module or unit or component, and in addition, they can be divided into multiple sub-modules or sub-units or sub-components. Except that at least some of such features and / or processes or units are mutually exclusive, any combination can be adopted to combine all the features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all the processes or units of any method or device so disclosed. Unless otherwise explicitly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) can be replaced by an alternative feature that provides the same, equivalent, or similar purpose.

[0197] Each component embodiment of the present application can be implemented in hardware, or in the form of software modules running on one or more processors, or in a combination thereof. Those skilled in the art should understand that a microprocessor or a digital signal processor (DSP) can be used in practice to implement some or all of the functions of some or all of the components in the sorting device according to the present application. The present application can also be implemented as a device or device program for executing some or all of the methods described herein. Such a program implementing the present application can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0198] It should be noted that the above embodiments illustrate the present application rather than limit the present application, and those skilled in the art can design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present application can be implemented by means of hardware including several different elements and by means of a suitably programmed computer. In the unit claims listing several devices, several of these devices can be embodied by the same hardware item. The use of the words first, second, and third, etc. does not denote any order. These words can be interpreted as names.

[0199] The user information involved in the present application (including but not limited to the user's device information, user personal information, etc.), relevant data, etc. are all information authorized by the user or authorized by all parties.

[0200] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments and will not be elaborated herein.

[0201] The foregoing are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall be included within the protection scope of the present application. As described above, these are only the specific implementation manners of the present application, but the protection scope of the present application is not limited thereto. Those skilled in the art within the technical scope disclosed in the present application can easily think of changes or replacements, which should all be covered by the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method for controlling a water heater, characterized in that: The method comprises: Get the set water temperature, current power, current water flow rate and the water flow rate at the last moment; Input the current power, the current water inflow rate and the water inflow rate at the previous moment into a feedforward controller to determine the power compensation amount or exit the compensation mode; the feedforward controller is a nonlinear compensation module; According to the set temperature and the power compensation amount, the water heater is subjected to an auto-disturbance rejection control process by a second-order nonlinear auto-disturbance rejection controller to generate a control power of the water heater; the proportional-integral parameter in the second-order nonlinear auto-disturbance rejection controller is determined according to the current water inlet flow rate; The water heater is controlled according to the control power to obtain the outlet water temperature of the water heater.

2. The method according to claim 1, characterized in that The step of inputting the current power, the current water inlet flow rate and the water inlet flow rate at the previous moment into a feedforward controller to obtain a power compensation amount or exit a compensation mode includes: Determining the flow difference between the current water inlet flow and the water inlet flow at the previous moment by the feedforward controller; In the case where the flow difference is greater than a preset flow threshold, determining the power compensation amount through the feedforward controller according to the current power and the flow difference; When the flow difference is less than or equal to the flow threshold, the compensation mode is exited through the feedforward controller.

3. The method according to claim 2, characterized in that When the flow difference is greater than a preset flow threshold, determining the power compensation amount by the feedforward controller according to the current power and the flow difference includes: In the case where the flow difference is greater than the flow threshold, determining the flow ratio of the flow difference to the water inlet flow at the previous moment by the feedforward controller; The feedforward controller multiplies the current power, the flow ratio and a preset feedforward coefficient as the power compensation amount.

4. The method according to claim 2, characterized in that: When the flow difference is less than or equal to the flow threshold, exiting the compensation mode through the feedforward controller includes: When the flow difference is less than or equal to the flow threshold, the power compensation amount is set to zero by the feedforward controller.

5. The method according to claim 1, characterized in that The second-order nonlinear auto-disturbance rejection controller comprises a differential tracker, a state error feedback module and a nonlinear extended state observer, wherein the differential tracker is connected to the nonlinear extended state observer through the state error feedback module, and the second-order nonlinear auto-disturbance rejection controller performs auto-disturbance rejection control on the water heater according to the set temperature and the power compensation amount to generate control power, including: Performing smooth transition calculation according to the set temperature by the differential tracker to generate a transition temperature; generating a total disturbance estimate through the nonlinear extended state observer; The state error feedback module performs compensation calculation according to the transition temperature, the power compensation amount, and the total disturbance estimation amount to generate control power.

6. The method according to claim 5, characterized in that The total disturbance estimation includes a temperature estimation value and a disturbance estimation value, and the state error feedback module generates a control power according to the transition temperature, the power compensation amount, and the total disturbance estimation value, including: The state error feedback module performs compensation calculation according to the transition temperature, the power compensation amount, the temperature estimation value and the disturbance estimation value to generate control power.

7. The method according to claim 1, characterized in that The step of controlling the water heater according to the control power to obtain the outlet water temperature of the water heater includes: According to the control power, the water heater is controlled by a pre-constructed physical model to obtain the outlet water temperature of the water heater.

8. The method according to claim 1, characterized in that The method further comprises: Obtaining the water inlet temperature of the water heater; The valve opening of the water heater is adjusted according to the current water inlet flow, the water inlet temperature, and the water outlet temperature of the water heater.

9. The method according to claim 8, characterized in that The valve of the water heater includes a proportional valve and a solenoid valve, and the valve opening of the water heater is adjusted according to the current water inlet flow, the water inlet temperature, and the water outlet temperature of the water heater, including: converting the control amount corresponding to the control power into a secondary pressure; converting the secondary voltage into a pulse width modulated signal; The opening of the proportional valve and the opening of the solenoid valve are controlled by the pulse width modulation signal.

10. A control device for a water heater, characterized in that: The device comprises: The acquisition module is used to obtain the set water temperature, current power, current water inlet flow rate and the water inlet flow rate at the previous moment; A feedforward control module, inputting the current power, the current water inlet flow rate and the water inlet flow rate at the previous moment into a feedforward controller, determining the power compensation amount or exiting the compensation mode; the feedforward controller is a nonlinear compensation module; A power generation module, configured to perform an auto-disturbance rejection control process on the water heater through a second-order nonlinear auto-disturbance rejection controller according to the set temperature and the power compensation amount, so as to generate control power for the water heater; the proportional-integral parameter in the second-order nonlinear auto-disturbance rejection controller is determined according to the current water inlet flow rate; The temperature control module is used to control the water heater according to the control power to obtain the outlet water temperature of the water heater.

11. An electronic device, characterized in that: include: A processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor implements the control method for the water heater according to any one of claims 1 to 9 when executing the program.

12. A readable storage medium, characterized in that: When the instructions or transactions in the storage medium are executed by a processor of an electronic device, the electronic device is enabled to execute the control method of the water heater according to any one of claims 1 to 9.

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