Electric water heater and control method

Abstract

The invention relates to the technical field of water heaters, and provides an electric water heater and a control method.The electric water heater comprises a box body, a high liquid level probe, a low liquid level probe, a liquid level emission probe and a controller, and a liquid storage space is formed in the box body; the low-liquid-level probe is arranged below the high-liquid-level probe, and the low-liquid-level probe is configured to be capable of switching between the modes of the electronic anode and the liquid level detection component; the liquid level emission probe is flush with the low liquid level probe or is positioned below the low liquid level probe; the high-liquid-level probe, the low-liquid-level probe and the liquid-level emission probe are all in communication connection with the controller, and the controller controls the low-liquid-level probe to be switched among different modes based on a preset strategy. According to the invention, the low liquid level probe is configured to be the electronic anode and the liquid level detection part, so that the two-in-one function of the electronic anode and the liquid level detection function is realized, the number of parts in the box body is reduced, the occupation of the parts on the space in the box body is reduced, the production cost is reduced, and the control system is simplified.

Description

Technical Field

[0001] This invention relates to the field of water heater technology, and more particularly to an electric water heater and its control method. Background Technology

[0002] Electric water heaters are a common household hot water device that uses electricity to heat tap water or water of suitable quality to a set temperature for daily use.

[0003] One typical electric water heater consists of a water tank, a heating element, and safety protection devices. It primarily heats the water in the tank to supply hot water for daily use. To ensure safe operation, the water tank contains a level sensor probe and an electronic anode component to prevent corrosion of the inner tank. This design results in a large number of components inside the tank, occupying considerable internal space, and numerous control elements connected to the controller, leading to a complex control circuit. Summary of the Invention

[0004] This invention provides an electric water heater and a control method to solve the defects of existing electric water heaters, which have many internal components, occupy a lot of internal space, and have complex control circuits.

[0005] The first aspect of the present invention provides an electric water heater, comprising: The housing has a liquid storage space. A high-level probe is used to detect the liquid level at the top of the storage space; A low-level probe is located below the high-level probe, and the low-level probe is configured to switch between the modes of an electronic anode and a level detection component. A liquid level emission probe is disposed within the liquid storage space and is flush with or below the low liquid level probe. The liquid level emission probe is used to form a circuit with the high liquid level probe or the low liquid level probe to realize the liquid level detection at their respective positions. The controller is connected to the high liquid level probe, the low liquid level probe and the liquid level emission probe. The controller controls the low liquid level probe to switch between different modes based on a preset strategy.

[0006] According to the electric water heater provided by the present invention, the electric water heater further includes a function switching module, which is disposed on the conductive circuit between the controller and the low liquid level probe, and the function switching module is used to switch the output mode.

[0007] According to the electric water heater provided by the present invention, an AD sampling module and an electronic anode drive module are electrically connected to the function switching module. Both the AD sampling module and the electronic anode drive module are electrically connected to the controller. The function switching module is used to switch the low liquid level probe to be electrically connected to the AD sampling module or the low liquid level probe to the electronic anode drive module.

[0008] According to the electric water heater provided by the present invention, the controller, the AD sampling module and the electronic anode drive module are integrated on a single control motherboard.

[0009] According to the electric water heater provided by the present invention, when the low liquid level probe is configured as an electronic anode, the operating voltage of the low liquid level probe is 1.7V-2.1V.

[0010] According to the electric water heater provided by the present invention, the electric water heater further includes a liquid level detection signal transmitting module, the liquid level detection signal transmitting module being electrically connected to the liquid level transmitting probe and the controller, and the liquid level detection signal transmitting module being used to transmit a liquid level detection signal.

[0011] According to the electric water heater provided by the present invention, the electric water heater further includes a water replenishment module, which is electrically connected to the controller and is used to control the water replenishment circuit to communicate with the tank.

[0012] According to the electric water heater provided by the present invention, the water supply module includes a constant temperature water supply valve, and the water supply circuit is connected to the housing through the constant temperature water supply valve.

[0013] According to the electric water heater provided by the present invention, the low liquid level probe includes a titanium alloy probe.

[0014] A second aspect of the present invention provides a control method for an electric water heater using any one of the above-described methods, comprising the following steps: Determine whether the heater in the electric water heater needs to be activated, and output the first determination result; The first judgment result is that when the heater is started, the low liquid level probe is configured as a liquid level detection component to determine whether the current liquid level has reached the preset liquid level, and the second judgment result is output. The second judgment result is that when the current liquid level is greater than the preset liquid level, the electric water heater is controlled to heat, the low liquid level probe is configured as an electronic anode, and the working voltage of the low liquid level probe is controlled to approach the preset voltage. The second judgment result is that when the current liquid level is less than or equal to the preset liquid level, the water supply circuit is controlled to replenish the liquid storage space until the high liquid level probe detects the liquid level signal; then the electric water heater is controlled to heat, the low liquid level probe is configured as an electronic anode, and the working voltage of the low liquid level probe is controlled to approach the preset voltage. The first judgment result is that when the heater is not started, the liquid level emission probe is turned off, the low liquid level probe is configured as an electronic anode, and the working voltage of the low liquid level probe is controlled to approach the preset voltage.

[0015] According to the control method provided by the present invention, controlling the operating voltage of the low liquid level probe to approach a preset voltage includes the following steps: The low liquid level probe is configured as an electronic anode, and periodically outputs a high level for duration T1 and a low level for duration T2; After the low level T2 duration is output, the low liquid level probe is switched to AD mode to detect the current potential value U2. Based on the difference between the current potential value U2 and the preset potential value U1, the duration of the high level T1 is adjusted to keep U2 near U1.

[0016] According to any of the above embodiments, the electric water heater and control method provided have at least the following beneficial effects: The present invention provides an electric water heater that combines the functions of electronic anode and liquid level detection by configuring a low liquid level probe as both an electronic anode and a liquid level detection component. This simplifies the number of components inside the tank, reduces the space occupied by parts inside the tank, lowers production costs, and simplifies the control system. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the electric water heater provided by the present invention.

[0019] Figure 2 This is a connection diagram of the control mainboard in the electric water heater provided by the present invention.

[0020] Figure 3 This is a flowchart illustrating the control method of the electric water heater of the present invention.

[0021] Figure 4 This is a schematic diagram of the logic flow of the control method for the electric water heater of the present invention.

[0022] Figure label: 10. Housing; 11. Liquid storage space; 20. High liquid level probe; 30. Low liquid level probe; 40. Liquid level emission probe; 50. Heater; 60. Heat exchanger; 70. Control main board; 71. Controller; 72. Function switching module; 73. Low liquid level AD sampling module; 74. Electronic anode drive module; 75. Liquid level detection signal transmission module; 76. High liquid level AD sampling module. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0024] In the description of the embodiments of this application, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0025] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0026] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0027] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0028] An electric water heater is a common household water heating device that uses electricity to heat tap water or water of suitable quality to a set temperature for daily use. It typically consists of a water tank and one or more heaters. To prevent the tank from drying out and for safety reasons, it usually has a safety protection device that allows for timely water replenishment to prevent dry burning.

[0029] In related technologies, to ensure the safe use of water heaters, a liquid level sensor probe and an electronic anode component to prevent corrosion of the inner tank are installed inside the water tank as safety protection components. This necessitates the separate installation of the electronic anode component and liquid level sensor probe in the liquid storage space to achieve real-time liquid level detection and anode corrosion protection. This results in a large number of components in the water tank and requires separate wiring for control, leading to a relatively complex control system.

[0030] Regarding the problems in related technologies, such as Figures 1-2As shown, the present invention provides an electric water heater, including a housing 10, a high liquid level probe 20, a low liquid level probe 30, a liquid level emission probe 40, and a controller 71. The housing 10 forms a liquid storage space 11. The high liquid level probe 20 is used to detect the liquid level in the upper part of the liquid storage space 11. The low liquid level probe 30 is located below the high liquid level probe 20 and is configured to switch between the modes of an electronic anode and a liquid level detection component. The liquid level emission probe 40 is located in the liquid storage space 11 and is flush with or below the low liquid level probe 30. The liquid level emission probe 40 is used to form a loop with the high liquid level probe 20 or the low liquid level probe 30 to realize the liquid level detection at their respective positions. The high liquid level probe 20, the low liquid level probe 30, and the liquid level emission probe 40 are all communicatively connected to the controller 71. The controller 71 controls the low liquid level probe 30 to switch between different modes based on a preset strategy. The water tank of an electric water heater is used to store heat exchange medium. The efficient heat exchange of cold water is achieved by heating the heat exchange medium. In this embodiment, three probes are configured in the water tank, and the low liquid level probe 30 is configured as an electronic anode or a liquid level detection component. This allows for the switching between electronic anode and liquid level detection components under different scenario requirements, reducing the number of components and simplifying the control system.

[0031] Specifically, structurally, both the high-level probe 20 and the low-level probe 30 are located in the upper region of the liquid storage space 11, with the low-level probe 30 positioned below the high-level probe 20. The liquid level emission probe 40 is not higher than the low-level probe 30, so that when the low-level probe 30 and the high-level probe 20 need to detect the liquid level, they can be electrically connected to the liquid level emission probe 40 to form a circuit, thereby achieving liquid level detection. In specific configurations, such as... Figure 1 The chamber 10 is equipped with a spiral heat exchanger 60 and a heater 50 at the bottom of the chamber 10. The low liquid level probe 30 and the liquid level emission probe 40 are arranged in parallel, that is, the low liquid level probe 30 and the liquid level emission probe 40 are on the same liquid level surface.

[0032] Understandably, in some principles for implementing liquid level detection, a reference point and a position detection point are usually required. In this embodiment, both the high-level probe 20 and the low-level probe 30 can serve as position detection points, while the liquid level emission probe 40 serves as the reference point. The reference point is a fixed point that forms an electrical loop when it is connected to the high-level probe 20 and the low-level probe 30. When the liquid level changes, the signal from the position detection point will reflect the height of the liquid level. The controller 71 monitors and adjusts the liquid level in real time based on the relationship between this signal and the reference point.

[0033] Generally, electric water heaters have two operating states. One state is when the heater 50 is operating. Initially, it's necessary to check if there is sufficient heat exchange medium in the storage space 11. At this time, the low-level probe 30 is configured as a level detection component to detect the liquid level in the storage space 11. When the detected liquid level is lower than the low-level probe 30, it indicates that the heat exchange medium in the water tank is insufficient, and water needs to be added promptly until the high-level probe 20 detects a corresponding signal. This indicates that there is sufficient heat exchange medium in the water tank, allowing the heater 50 to be activated for heating. After heating is activated, corrosion prevention is required within the water tank. At this time, the low-level probe 30 is configured as an electronic anode to protect the water tank.

[0034] Another scenario is that the heater 50 is in a non-heating state during normal operation. In this state, liquid level detection is not required, the liquid level emission probe 40 is turned off, and the low liquid level probe 30 is configured as an electronic anode, thus providing corrosion protection for the water tank. In other words, the low liquid level probe 30 needs to be configured as a liquid level detection component before the water heater 50 is turned on. In other states, it can be configured as an electronic anode, enabling the low liquid level probe 30 to be used in multiple ways, reducing the cost of the water heater and simplifying the control system.

[0035] In specific settings, the low liquid level probe 30 is made of titanium alloy, which has excellent corrosion resistance, strength and high temperature resistance, thus enabling it to perform the dual functions of a liquid level detection component and an electronic anode, reducing the number of components in the water tank and simplifying the control system.

[0036] In some specific embodiments, both the low-level probe 30 and the high-level probe 20 are located at the upper part of the liquid storage space 11, with the low-level probe 30 located below the high-level probe 20, thereby enabling the detection of lower liquid levels. This arrangement ensures that even when the liquid level is lower than the low-level probe 30, the overall liquid level still has a certain height, further preventing dry burning and improving safety performance.

[0037] It should be understood that in this embodiment, both the high-level probe 20 and the low-level probe 30 are located in the liquid storage space 11. The level of the liquid is relative to the storage limit of the liquid storage space 11, so the designations of the high-level probe 20 and the low-level probe 30 are clear. The high-level probe 20 refers to the storage limit close to the liquid storage space 11, and the low-level probe 30 refers to the storage limit far from the liquid storage space 11.

[0038] In some embodiments of the present invention, the electric water heater further includes a function switching module 72. The function switching module 72 is disposed on the conductive circuit between the controller 71 and the low liquid level probe 30, and is used to switch the output mode. The switching of the low liquid level probe 30 between different modes can be achieved in various ways. In this embodiment, by configuring the function switching module 72 hardware, the switching of different functions can be realized, which simplifies the control design and provides high flexibility.

[0039] The low-level probe 30 can switch between different modes via software configuration or an embedded system during different switching operations. In this embodiment, by setting up a function switching module 72, the modular design reduces the overall system complexity and facilitates maintenance and upgrades. Modules can be easily added or replaced to achieve new functions, supporting long-term system iteration.

[0040] Specifically, the low liquid level probe 30 is connected to the controller 71 via wires or other conductive circuits, and the function switching module 72 is located between the two. The controller 71 can output control signals to control the conduction of different circuits under different requirements.

[0041] In specific configurations, a switching circuit or relay can be installed inside the function switching module 72, which can selectively connect or disconnect with different functional units according to control signals. For example, when configured as a liquid level detection component, the controller outputs a specific voltage or other electrical signal, enabling the function switching module 72 to connect with the AD module and form a loop with the liquid level transmitting probe 40, thereby achieving liquid level detection. Similarly, when an electronic anode function is required, the controller 71 outputs another specific voltage or other electrical signal, enabling the function switching module 72 to connect to the electronic anode unit under the action of the control signal, configuring it as an electronic anode. Of course, control signals can also be issued by the microcontroller 71 or PLC to instruct the function switching module 72 to activate specific connections. For example, if data acquisition is required, the signal is directed to the detection functional unit; if electronic anode function is required, it is connected to the electronic anode functional unit.

[0042] As described above, the function switching module 72 in this embodiment can effectively switch modes and achieve rapid switching under the control of the controller 71, thereby giving it a better response speed and improving control accuracy. It should be understood that the corresponding peripheral circuits differ in different modes, and the detection circuit for the liquid level detection component, as well as the functional circuit when configured as an electronic anode, can be circuits found in existing conventional technologies. Therefore, further details will not be provided.

[0043] According to the embodiments provided by the present invention, an AD sampling module and an electronic anode drive module 74 are electrically connected to the function switching module 72. Both the AD sampling module and the electronic anode drive module 74 are electrically connected to the controller 71. The function switching module 72 is used to switch the low liquid level probe 30 to be electrically connected to the AD sampling module or to the electronic anode drive module 74. The modular design facilitates the configuration and connection of components, resulting in higher design flexibility, expandability, and maintainability.

[0044] It is understandable that the AD sampling module and the electronic anode drive module 74 can perform different functions. When connected to the AD sampling module, it can perform voltage measurement and combine with the liquid level emission probe 40 to form a liquid level detection component, thereby detecting the liquid level. When connected to the electronic anode drive module 74, the low liquid level probe 30 can be configured as an electronic anode, thereby achieving corrosion prevention of the water tank.

[0045] In a specific example, the high-level probe 20 is connected to a high-level AD sampling module 76, which is electrically connected to the controller 71. The high-level AD sampling module 76 is used to convert the analog liquid level signal obtained from the high-level probe 20 into a digital signal for subsequent processing. It forms a liquid level detection loop with the low-level probe 30, and real-time liquid level acquisition is achieved under the control of the controller.

[0046] In some embodiments, the controller 71, the AD sampling module, and the electronic anode drive module 74 are integrated onto a single control motherboard 70. This integration of the modules and controller reduces the overall footprint, allowing the electric water heater to have a larger heating space.

[0047] Understandably, different areas are set up on the control motherboard 70 to house different modules and controllers 71, so that additions and subtractions can be made according to functions during modular design. The overall layout allows the device to occupy less space.

[0048] Specifically, after being integrated onto the control motherboard 70, the various components are electrically connected in a patterned manner, which reduces the number of external wires and components, saves space, improves the system's compactness, and facilitates mass production.

[0049] In the embodiments provided by the present invention, when the low liquid level probe 30 is configured as an electronic anode, the operating voltage of the low liquid level probe 30 is 1.7V-2.1V. By limiting the operating voltage of the low liquid level probe 30 to 1.7V-2.1V, energy efficiency can be improved, giving it higher energy efficiency.

[0050] In a preferred example, the low liquid level probe 30 operates at a voltage of 1.9V. At this operating voltage, it can achieve good energy efficiency control and provide a stable and reliable output signal.

[0051] Specifically, when used as an electronic anode, the low-level probe 30 operates at a lower voltage. A lower operating voltage reduces power consumption, thereby improving energy efficiency. Furthermore, operating within this voltage range reduces noise interference, improves signal stability and reliability, and low-voltage designs often require fewer complex circuits and components, reducing design difficulty and cost.

[0052] In one embodiment of the present invention, the electric water heater further includes a liquid level detection signal transmitting module. The liquid level detection signal transmitting module is electrically connected to the liquid level transmitting probe 40 and the controller 71, and the liquid level detection signal is used to transmit a liquid level detection signal. The liquid level transmitting probe 40 is connected to the controller 71 through the liquid level detection signal transmitting module. When liquid level detection is required, the module needs to be connected to the controller 71 to achieve liquid level detection. In this embodiment, the liquid level detection signal transmitting module can transmit liquid level detection information and process the detected signal to achieve liquid level detection.

[0053] Specifically, the liquid level transmitting probe 40 serves as the base point for liquid level detection, directly contacting the liquid within the storage space 11. It can generate corresponding analog signals (such as voltage or current) based on changes in the liquid level, reflecting the liquid level height. After the probe outputs a signal, the signal modulation circuit amplifies, filters, and converts the original signal to improve its stability and accuracy, ensuring it is suitable for subsequent processing. These signals are processed by the liquid level detection signal transmitting module and then sent to the controller 71. Real-time monitoring of the liquid level is achieved through the low-level AD sampling module 73 or the high-level AD sampling module 76, which is connected to the controller.

[0054] In some embodiments of the present invention, the electric water heater further includes a water replenishment module, which is electrically connected to the controller 71 and is used to control the connection between the water replenishment circuit and the tank 10. During long-term use, the electric water heater requires heating the heat exchange medium to heat the water. This causes the heat exchange medium (such as water) to gradually decrease under the action of the heater 50. To maintain a good liquid level in the storage space 11, in this embodiment, the water replenishment module replenishes the water in the storage space 11 within the tank 10, preventing dry burning and improving overall safety.

[0055] In a specific embodiment, water is stored in the liquid storage space 11 as a heat exchange medium. A water replenishment module is connected to the liquid storage space 11. The water replenishment module can be a water replenishment system, that is, a water replenishment pipeline connected to the outside and equipped with an electrically controlled valve on the water replenishment pipeline. The electrically controlled valve is electrically connected to the controller 71, so that the water replenishment pipeline can be opened or closed under the control of the controller 71. When water replenishment is required, water is introduced into the liquid storage space 11 by opening the electrically controlled valve to realize the water replenishment operation. When the water replenishment reaches a preset position (which can be when the high liquid level probe 20 detects a liquid level signal), the water replenishment pipeline is closed, thereby realizing the control of the water replenishment volume.

[0056] It is understandable that when an electric water heater heats water, it needs to ensure that there is sufficient heat exchange medium in the storage space 11 to achieve effective heat exchange and prevent the water heater from burning dry, which could lead to damage. In this embodiment, when the low liquid level probe 30 detects that the water level is below a certain position, it can promptly replenish water, thereby preventing the water heater from burning dry and improving the safety performance of the equipment.

[0057] In some embodiments, the water replenishment module includes a thermostatic water replenishment valve, and the water replenishment path is connected to the housing 10 through the thermostatic water replenishment valve. The thermostatic water replenishment valve is used to input water into the liquid storage space 11 when needed. In this embodiment, the setting of a thermostatic water replenishment valve can keep the incoming water at a preset working temperature and prevent excessive water temperature fluctuations in the liquid storage space 11.

[0058] Specifically, a water supply pipe is installed outside the electric water heater, and a thermostatic water supply valve is installed on the water supply pipe. The thermostatic water supply valve can adjust the water supply temperature, reduce the energy consumption of heating, and achieve energy saving. Moreover, through the function of the thermostatic water supply valve, the water supply temperature is kept within a relatively optimal temperature range, which can improve the operating efficiency and stability of the system.

[0059] In a further example, the thermostatic water supply valve is electrically connected to the controller 71, which can issue control signals based on a preset strategy to control the opening and closing of the thermostatic water supply valve.

[0060] For example, before starting the heater 50 in the electric water heater, the liquid level of the heat exchange medium in the current storage space 11 needs to be detected. When the liquid level is lower than the low liquid level probe 30, water replenishment is required. At this time, the controller 71 sends a control signal based on the detection data collected by the low liquid level probe 30, controlling the thermostatic water replenishment valve to open, so that water is input into the storage space 11 through the thermostatic water replenishment valve, thereby achieving water replenishment of the storage space 11 and ensuring that the heat exchange medium in the replenishment space has a safe liquid level. In this way, automatic water replenishment can be achieved, and by configuring the low liquid level probe 30 as a liquid level detection component, feedback of liquid level detection and acquisition signals can be achieved, thus realizing timely water replenishment.

[0061] like Figure 3 , Figure 4 As shown, the present invention also provides a control method for an electric water heater using any of the above-mentioned methods, comprising the following steps: S10. Determine whether the heater 50 in the electric water heater needs to be started, and output the first determination result. The main controller 71 receives the current operation information to determine whether heating is required. When the first determination result is to start the heater 50, steps S20-S22 are executed; when the first determination result is not to start the heater 50, step S30 is executed.

[0062] S20. When the heater 50 needs to be started, the low liquid level probe 30 is configured as a liquid level detection component to determine whether the current liquid level has reached the preset liquid level and output a second judgment result. Before starting the water heater, it is necessary to determine whether the liquid level is at the preset safe position. At this time, it is necessary to perform detection and judgment through the low liquid level probe 30 to achieve liquid level detection. The controller 71 outputs judgment information based on the detection result.

[0063] Specifically, before the electric water heater starts, the low-level probe 30 is configured as a liquid level detection component to detect the current liquid level in the storage space 11 and output a judgment result indicating whether the liquid level is greater than the preset liquid level. In a specific setting, for safe heating, the electric water heater needs to detect whether the current liquid level meets the preset liquid level requirement before the heater 50 starts. At this time, the function switching module 72 is configured to connect the low-level probe 30 to the AD sampling module and form a detection loop with the low-level transmitting probe 40, thereby enabling the detection of whether the liquid level in the current storage space 11 is higher than that of the low-level probe 30.

[0064] S21. When the second judgment result is that the current liquid level is greater than the preset liquid level, the electric water heater is controlled to heat, the low liquid level probe 30 is configured as an electronic anode, and the operating voltage of the low liquid level probe 30 is controlled to approach the preset voltage. The output result "yes" indicates that the current liquid level is greater than the preset liquid level, which means that there is a sufficient liquid level in the liquid storage space 11 to achieve effective heating. At this time, it is configured as an electronic anode to provide corrosion protection.

[0065] Specifically, after receiving the liquid level feedback information from the low-level probe 30, the main controller 71 indicates that the liquid level in the storage space 11 is not lower than the height of the low-level probe 30, and at this time, the heater 50 can be turned on for heating. Correspondingly, under the control of the controller 71, the low-level probe 30 is connected to the electronic anode drive module 74 through the function switching module 72, so that the low-level probe 30 is configured as an electronic anode, realizing the corrosion prevention function of the low-level probe 30.

[0066] S22. When the judgment result is that the current liquid level is less than or equal to the preset liquid level, the water supply circuit is controlled to replenish water to the storage space 11 until the high liquid level probe 20 detects a liquid level signal. Then, the electric water heater is controlled to heat the water, and the low liquid level probe 30 is configured as an electronic anode, and the operating voltage of the low liquid level probe 30 is controlled to approach the preset voltage. When the low liquid level probe 30 does not report any liquid level information, it means that the heat exchange medium level in the storage space is insufficient and water replenishment is required. At this time, water replenishment is carried out through the water supply circuit. After the high liquid level probe 20 detects liquid level information, it means that there is sufficient liquid level in the storage space 11 for heating. At this time, the heater 50 can be turned on, and the low liquid level probe 30 is configured as an electronic anode to achieve the anti-corrosion function.

[0067] Specifically, the controller 71 first detects the liquid level through a liquid level detection loop formed by the low-level probe 30 and the liquid level transmitting probe 40. If no liquid level is detected, it indicates that the liquid level is below the position of the low-level probe 30. The controller 71 sends a water replenishment command to the water replenishment module, which processes the command and controls the opening of the thermostatic water replenishment valve to achieve thermostatic water replenishment. When the replenished liquid level reaches the high-level probe 20, the high-level probe 20 sends a feedback signal, and the controller 71 can issue a command to stop water replenishment. During the entire water replenishment process, the low-level probe 30 can be closed, allowing the high-level probe 20 and the liquid level transmitting probe 40 to form a liquid level detection loop, enabling feedback of liquid level information when the liquid level reaches the high-level probe 20 and stopping water replenishment. After water replenishment is completed, the low-level probe 30 is switched to electronic anode mode via the function switching module 72, thereby achieving corrosion prevention.

[0068] S30. When the first judgment result is that the heater 50 is not started, the liquid level emission probe 40 is turned off, the low liquid level probe 30 is configured as an electronic anode, and the working voltage of the low liquid level probe 30 is controlled to approach the preset voltage.

[0069] S40. Configure the low liquid level probe 30 to electronic anode mode and periodically output a high level for duration T1 and a low level for duration T2. ​​After outputting a low level for duration T2, switch the low liquid level probe 30 to liquid level AD sampling mode and measure the current potential value U2. Adjust the duration of the high level T1 according to the difference between the current potential value U2 and the preset potential value U1, so that U2 is maintained near U1, and the operating voltage of the low liquid level probe 30 tends to the preset voltage.

[0070] It is understandable that in steps S30, S21 and S22, it is necessary to control the operating voltage of the low liquid level probe 30 to approach the preset voltage. The method in S40 can be used to maintain the operating voltage of the low liquid level probe 30 near the preset voltage.

[0071] Specifically, the period during which heater 50 does not need to be activated is the normal period, and the main purpose during this period is to prevent corrosion. Specifically, controller 71 connects the low-level probe 30 to the electronic anode drive module 74 via function switching module 72. At this time, the level detection signal transmission module is turned off, preventing the level transmitting probe 40 from forming a detection loop with the low-level probe 30 and the high-level probe 20, thus eliminating level detection. When connected to the electronic anode drive module 74, it periodically outputs a high level for duration T1, and then switches to connection with the AD sampling module after a low level for duration T2. ​​Since the level transmitting probe 40 is turned off, a detection loop is not formed. Instead, the AD sampling module measures the current potential value U2, and the controller adjusts the duration of the high level T1 based on the difference between U2 and the preset U1, thereby maintaining optimal corrosion prevention.

[0072] For example, when the difference between U2 and the preset U1 is large, the duration of the high level T1 needs to be extended so that the potential value U2 throughout the detection cycle is closer to the preset potential value U1, thereby making the operating voltage of the low liquid level probe 30 closer to the preset voltage. Of course, when the difference between U2 and the preset U1 is small, the current duration of the high level T1 can be maintained, thus achieving a better anti-corrosion effect.

[0073] Through the above description of the embodiments, those skilled in the art can clearly understand that by configuring the low-level probe as both an electronic anode and a level detection component, the functions of electronic anode and level detection are combined into one, simplifying the number of components inside the tank, reducing the space occupied by the components, lowering production costs, and simplifying the control system. Furthermore, the provided control method enables the low-level probe to have better corrosion resistance and can quickly switch between different modes to achieve automated operation.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electric water heater, characterised in that, The electric water heater comprises: a box body, which forms a liquid storage space; a high liquid level probe, which is used to detect the liquid level at the upper part of the liquid storage space; a low liquid level probe, which is arranged below the high liquid level probe and is configured to switch between an electronic anode mode and a liquid level detection component mode; a liquid level emitting probe, which is arranged in the liquid storage space and is flush with or below the low liquid level probe, and is used to form a loop with the high liquid level probe or the low liquid level probe to detect the liquid level at the respective position; a controller, which is in communication connection with the high liquid level probe, the low liquid level probe and the liquid level emitting probe, and controls the low liquid level probe to switch between different modes based on a preset strategy.

2. The electric water heater according to claim 1, characterized in that The electric water heater further comprises a function switching module, which is arranged on the conduction circuit between the controller and the low liquid level probe, and is used to switch the output mode.

3. The electric water heater according to claim 2, wherein An AD sampling module and an electronic anode driving module are electrically connected with the function switching module, and the AD sampling module and the electronic anode driving module are electrically connected with the controller, and the function switching module is used to switch the electrical connection between the low liquid level probe and the AD sampling module or between the low liquid level probe and the electronic anode driving module.

4. The electric water heater according to claim 3, wherein The controller, the AD sampling module and the electronic anode driving module are integrated on a control mainboard.

5. The electric water heater according to claim 1, wherein When the low liquid level probe is configured as an electronic anode, the working voltage of the low liquid level probe is 1.7V-2.1V.

6. The electric water heater according to claim 1, wherein The electric water heater further comprises a liquid level detection signal sending module, which is electrically connected with the liquid level emitting probe and the controller, and is used to send a liquid level detection signal.

7. The electric water heater according to claim 1, wherein The electric water heater further comprises a water replenishment module, which is electrically connected with the controller, and is used to control a water replenishment waterway to be in communication with the box body.

8. The electric water heater according to claim 7, wherein The water replenishment module comprises a constant temperature water replenishment valve, and the water replenishment waterway is connected with the box body through the constant temperature water replenishment valve.

9. The electric water heater according to claim 1, wherein The low liquid level probe comprises a titanium alloy probe.

10. A control method for an electric water heater according to any one of claims 1 to 9, characterized in that, The method comprises the following steps: determining whether the heater in the electric water heater needs to be started, and outputting a first determination result; when the first determination result is to start the heater, configuring the low liquid level probe as a liquid level detection component, determining whether the current liquid level reaches a preset liquid level, and outputting a second determination result; when the second determination result is that the current liquid level is greater than the preset liquid level, controlling the electric water heater to heat, configuring the low liquid level probe as an electronic anode, and controlling the working voltage of the low liquid level probe to approach a preset voltage; when the second determination result is that the current liquid level is less than or equal to the preset liquid level, controlling the water replenishment waterway to perform water replenishment operation on the liquid storage space until the high liquid level probe detects a liquid level signal; then controlling the electric water heater to heat, configuring the low liquid level probe as an electronic anode, and controlling the working voltage of the low liquid level probe to approach a preset voltage; When the first judgment result is that the heater is not started, the liquid level emission probe is closed, the low liquid level probe is configured as an electronic anode, and the working voltage of the low liquid level probe is controlled to approach a preset voltage.

11. The control method according to claim 10, characterized by, The working voltage of the low liquid level probe is controlled to approach the preset voltage, including the following steps: The low liquid level probe is configured as an electronic anode, and a high-level T1 duration and a low-level T2 duration are periodically output. After the low-level T2 duration is output, the low liquid level probe is switched to an AD adoption mode, a current potential value U2 is detected, the duration of the high-level T1 is adjusted based on a difference between the current potential value U2 and a preset potential value U1, so that U2 is maintained near U1.

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