A liner anti-corrosion control method and device and electric water heater

Abstract

The application provides a liner anti-corrosion control method and device and an electric water heater, and belongs to the anti-corrosion technology of the electric water heater. A first control signal is sent to a switch unit to make a first loop conductive and a second loop non-conductive. A sampling current signal output by a first current sampling unit is received, and a first current is determined. A second control signal is sent to the switch unit to make the first loop non-conductive and the second loop conductive. A third control signal is sent to a variable voltage output unit to adjust the output voltage of the variable voltage output unit, and a second current same as the first current is generated on the second loop. Since the second current is obtained by referring to the first current, the interference of electrode polarization, water body properties and liner fouling and the like is effectively avoided, the potential of the liner is ensured to be within a specified range, the anti-corrosion effect is improved, and the anti-corrosion cost is reduced since no reference electrode is needed. In addition, the sacrificial anode does not need to work all the time in actual use, and the service life of the sacrificial anode can be prolonged.

Description

Technical Field

[0001] This invention relates to corrosion prevention technology for electric water heaters, and in particular to a method, device, and electric water heater for controlling corrosion of the inner tank. Background Technology

[0002] Corrosion prevention of the inner tank of electric water heaters has always been a key issue in the industry. Currently, there are two common solutions: one is the sacrificial anode cathodic protection method, which involves installing a magnesium rod on the inner tank. However, the magnesium rod will produce a large amount of magnesium carbonate and magnesium hydroxide precipitates during consumption, which will pollute the water quality, increase hardness, and require regular replacement of the magnesium rod.

[0003] Another type is electronic anodic protection using an external current. This method uses stable metals such as titanium or platinum as auxiliary electrodes, and the highly reactive inner tank and heating element as working electrodes. A DC power supply continuously provides electrons to the working electrodes, making the potential of the inner tank and heating element negative to their redox potential, thus preventing corrosion. This method does not increase water hardness or introduce excess sediment, but it fails to provide protection after power is cut off. Electronic anodic protection can be divided into systems with and without reference electrodes. Electronic anodic systems with reference electrodes ensure the cathode's protective potential remains within a specified range by detecting the potential difference between the reference electrode and the cathode. Systems without reference electrodes determine the inner tank's protection status by spontaneously detecting the potential at the electronic anode. The former, based on physical properties, is more accurate but requires more space and is more expensive; the latter relies on the accuracy of preset system parameters and is more significantly affected by electrode polarization, water properties, and scale buildup in the inner tank. Summary of the Invention

[0004] The first technical problem solved by this invention is to provide a method for controlling corrosion of the inner liner, which effectively extends the service life of the sacrificial anode, improves the accuracy of the current on the electronic anode, thereby improving the corrosion protection effect and reducing the corrosion protection cost.

[0005] The second technical problem solved by this invention is to provide an inner liner corrosion control device that effectively extends the service life of the sacrificial anode, improves the accuracy of the current on the electronic anode, thereby improving the corrosion protection effect and reducing the corrosion protection cost.

[0006] The third technical problem solved by this invention is to provide an electric water heater that effectively extends the service life of the sacrificial anode, improves the accuracy of the current on the electronic anode, thereby improving the anti-corrosion effect and reducing the anti-corrosion cost.

[0007] The first technical problem mentioned above is solved by the following technical solution:

[0008] A method for controlling corrosion prevention of an inner liner, applied to an inner liner corrosion prevention device, the inner liner corrosion prevention device comprising a sacrificial anode, an electronic anode, a first current sampling unit, a variable voltage output unit, a switching unit, and a controller. The sacrificial anode and the electronic anode are disposed within the inner liner. A first terminal of the first current sampling unit is connected to the sacrificial anode, and a second terminal of the first current sampling unit is connected to the inner liner, forming a first circuit. A first terminal of the variable voltage output unit is connected to the electronic anode, and a second terminal of the variable voltage output unit is connected to the inner liner, forming a second circuit. The switching unit controls the on / off state of the first circuit and the second circuit. The controller is connected to the first current sampling unit, the switching unit, and the variable voltage output unit respectively. The method includes:

[0009] A first control signal is sent to the switching unit, the first control signal being used to turn on the first circuit and turn off the second circuit;

[0010] During the conduction of the first circuit, the sampled current signal output by the first current sampling unit is received, and the first current is determined based on the sampled current signal;

[0011] A second control signal is sent to the switching unit, the second control signal being used to disconnect the first circuit and connect the second circuit;

[0012] A third control signal is sent to the variable voltage output unit to adjust the output voltage of the variable voltage output unit and generate a second current in the second circuit that is the same as the first current.

[0013] The corrosion prevention control method for the inner liner provided by this invention sends a first control signal to a switching unit. This first control signal is used to connect a first circuit and disconnect a second circuit. The sacrificial anode replaces the protected inner liner in undergoing an oxidation reaction, generating a current in the first circuit. During the first circuit's conduction, a sampling current signal output by a first current sampling unit is received, and a first current is determined based on this signal. Then, a second control signal is sent to the switching unit, which disconnects the first circuit and connects the second circuit. A third control signal is sent to a variable voltage output unit, which adjusts the output voltage of the variable voltage output unit to generate a second current in the second circuit, identical to the first current, thus achieving the purpose of corrosion prevention for the inner liner. Since the second current is obtained by referring to the first current of the sacrificial anode, interference from electrode polarization, water properties, and scale buildup in the inner liner can be effectively avoided, thereby improving the corrosion prevention effect. Furthermore, since no reference electrode is required, the corrosion prevention cost is reduced. It is understood that the electronic anode primarily provides protection when energized, while the sacrificial anode provides protection after power is off, further improving the corrosion prevention effect. In addition, the sacrificial anode does not need to operate continuously, thus extending its service life.

[0014] In one embodiment, the first control signal is used to control the first circuit to be turned on for a first preset duration, and the first current is the average value of the sampled current corresponding to the sampled current signal within the first preset duration.

[0015] In one embodiment, after issuing a third control signal to the variable voltage output unit, the method further includes:

[0016] The on-time of the second circuit is accumulated;

[0017] Determine whether the conduction duration of the second circuit reaches a second preset duration, wherein the second preset duration is longer than the first preset duration;

[0018] If so, the current round of control operation is completed, and the process returns to the step of sending the first control signal to the switch unit to enter the next round of control operation until the electric water heater is turned off.

[0019] If not, return to the step of accumulating the conduction time of the second circuit.

[0020] In one embodiment, the inner liner corrosion protection device further includes a second current sampling unit connected in series with the variable voltage output unit and connected to the controller. After sending a third control signal to the variable voltage output unit, the device further includes:

[0021] Obtain the sampled current signal output by the second current sampling unit;

[0022] The voltage output by the variable voltage output unit is adjusted by feedback based on the sampled current signal output by the second current sampling unit, so that the second current in the second circuit is the same as the first current.

[0023] In one embodiment, the liner corrosion control method further includes:

[0024] If the sampling current signal output by the first current sampling unit is not received after the first control signal is sent to the switching unit, it is determined that the sacrificial anode installation is faulty or the switching unit is faulty.

[0025] If the sampling current signal output by the second current sampling unit is not received after the second control signal is sent to the switching unit, it is determined that the electronic anode installation is faulty or the switching unit is faulty.

[0026] If the sampling current signals output by the first current sampling unit and the second current sampling unit are received simultaneously, it is determined that the switching unit has malfunctioned.

[0027] In one embodiment, the inner wall of the inner liner is enamel-lined, and after determining the first current based on the sampled current signal, the method further includes:

[0028] If the first current is less than or equal to the first preset value, then the enamel on the inner wall of the inner liner is determined to be intact.

[0029] If the first current is greater than the first preset value and less than or equal to the second preset value, it is determined that the enamel on the inner wall of the inner liner has a minor damage and enters the repair mode until the first current is less than or equal to the first preset value; in the repair mode, the conduction time of the first circuit is greater than the conduction time of the second circuit.

[0030] If the first current is greater than the second preset value, it is determined that the enamel on the inner wall of the inner liner has suffered significant damage, and a maintenance prompt signal is output.

[0031] In one embodiment, the liner corrosion control method further includes:

[0032] Each time the electric water heater is turned on, or according to a preset cycle, it is determined whether the current first current is less than the current threshold, which represents the minimum current value at which the sacrificial anode needs to be replaced.

[0033] If so, a second control signal is sent to the switching unit, along with a prompt message to remind the user to replace the sacrificial anode;

[0034] Obtain the current water temperature of the inner tank;

[0035] Based on the mapping relationship between current and water temperature, the third current required by the second circuit under the current water temperature condition is obtained;

[0036] A fourth control signal is sent to the variable voltage output unit, which is used to adjust the output voltage of the variable voltage output unit and generate a fourth current in the second circuit that is the same as the third current.

[0037] In one embodiment, the liner corrosion control method further includes:

[0038] During a set period after the electric water heater is initially turned on, multiple water temperatures and a first current corresponding to each water temperature are acquired.

[0039] The multiple water temperatures are divided into multiple temperature ranges, and a first current is determined for each temperature range.

[0040] Construct a mapping table between the first current and the temperature range as a mapping relationship between current and water temperature;

[0041] Based on the mapping relationship between current and water temperature, the third current required by the second circuit under the current water temperature condition is obtained, including:

[0042] Determine the target temperature range in which the current water temperature falls;

[0043] The current corresponding to the target temperature range is found from the mapping table and used as the third current required by the second circuit under the current water temperature condition.

[0044] In one embodiment, the liner corrosion control method further includes:

[0045] During a set period after the electric water heater is initially turned on, multiple water temperatures and a first current corresponding to each water temperature are acquired.

[0046] Divide multiple water temperatures into multiple temperature ranges;

[0047] For each temperature range, based on the first current corresponding to the endpoint temperature of the temperature range, a linear functional relationship between current and water temperature is constructed as a mapping relationship between current and water temperature.

[0048] Based on the mapping relationship between current and water temperature, the third current required by the second circuit under the current water temperature condition is obtained, including:

[0049] Determine the target temperature range in which the current water temperature falls;

[0050] Substitute the current water temperature into the mapping relationship corresponding to the target temperature range to calculate the third current required by the second circuit under the current water temperature condition.

[0051] In one embodiment, within the temperature range, the mapping relationship between current and water temperature is as follows:

[0052]

[0053] in, The current water temperature, The third current required by the second circuit under the current water temperature conditions. This is the maximum temperature within the specified temperature range. The minimum temperature within the stated temperature range. The first current corresponding to the maximum temperature within the stated temperature range. The first current corresponds to the minimum temperature within the temperature range.

[0054] The second technical problem mentioned above is solved by the following technical solution:

[0055] A liner corrosion prevention control device, used to perform the liner corrosion prevention control method as described above, comprising:

[0056] A first control module is configured to send a first control signal to the switching unit, wherein the first control signal is configured to turn on the first circuit and turn off the second circuit.

[0057] The receiving and determining module is used to receive the sampled current signal output by the first current sampling unit during the conduction of the first circuit, and determine the first current based on the sampled current signal;

[0058] The second control module is used to send a second control signal to the switching unit. The second control signal is used to control the first circuit to disconnect and to make the second circuit to conduct.

[0059] The third control module is used to send a third control signal to the variable voltage output unit. The third control signal is used to adjust the output voltage of the variable voltage output unit and generate a second current in the second circuit that is the same as the first current.

[0060] The third technical problem mentioned above is solved by the following technical solution:

[0061] An electric water heater includes a controller for performing an inner tank corrosion prevention control method as provided in the foregoing embodiments of the present invention. Attached Figure Description

[0062] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0063] Figure 1 A circuit diagram of an anti-corrosion device for an inner liner provided by the present invention;

[0064] Figure 2 Circuit diagram of another anti-corrosion device for the inner liner provided by the present invention;

[0065] Figure 3 A flowchart of an inner liner corrosion prevention control method provided by the present invention;

[0066] Figure 4 A flowchart of another method for controlling corrosion of the inner liner provided by the present invention;

[0067] Figure 5 This is a schematic diagram of the structure of an inner liner corrosion prevention control device provided by the present invention;

[0068] Figure 6 This is a schematic diagram of the structure of an electronic device provided by the present invention. Detailed Implementation

[0069] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0070] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. In the description of this application, unless otherwise stated, "a plurality of" means two or more. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0071] The technical solution of the present invention will be illustrated below through specific embodiments.

[0072] Figure 1 A circuit diagram of an anti-corrosion device for an inner liner provided by the present invention is shown below. Figure 1 As shown, the inner tank corrosion protection device includes a sacrificial anode 10, an electronic anode 20, a first current sampling unit 30, a variable voltage output unit 40, a switching unit 50, and a controller 60. The sacrificial anode 10 and the electronic anode 20 are disposed inside the inner tank 1 of the electric water heater, and the inner tank 1 is grounded. The first end of the first current sampling unit 30 is connected to the sacrificial anode 10, and the second end of the first current sampling unit 30 is connected to the inner tank 1, forming a first circuit. The first current sampling unit 30 is used to collect the current signal in the first circuit. The first end of the variable voltage output unit 40 is connected to the electronic anode 20, and the second end of the variable voltage output unit 40 is connected to the inner tank 1, forming a second circuit. The output voltage of the variable voltage output unit 40 is adjustable. The switching unit 50 is disposed on the first circuit and the second circuit, and the switching unit 50 is used to control the on / off state of the first circuit and the second circuit. The controller 60 is connected to the first current sampling unit 30, the switching unit 50, and the variable voltage output unit 40, respectively.

[0073] For example, such as Figure 1 As shown, in a specific embodiment of the present invention, the switching unit 50 includes a first control switch SW1 and a second control switch SW2. The first control switch SW1 is connected in series between the sacrificial anode 10 and the first current sampling unit 30. The first end of the first control switch SW1 is connected to the sacrificial anode 10, the second end of the first control switch SW1 is connected to the first end of the first current sampling unit 30, and the control terminal of the first control switch SW1 is connected to the controller 60. The second control switch SW2 is connected in series with the variable voltage output unit 40. The first end of the second control switch SW2 is connected to the second end of the variable voltage output unit 40, the second end of the second control switch SW2 is connected to the inner liner 1, and the control terminal of the second control switch SW2 is connected to the controller 60.

[0074] It should be noted that in the above embodiments, the sacrificial anode 10 can be a magnesium rod, and the electronic anode 20 can be an auxiliary electrode made of inert metals such as titanium or platinum. The first current sampling unit 30 can be a conventional AD sampling circuit, which collects continuous current signals (analog signals) and converts them into discrete digital signals. The variable voltage output unit 40 can be a DC power supply with adjustable output voltage. The controller 60 can be a microcontroller. It can be understood that the inner liner 1 is a metal liner, the outer wall of the inner liner 1 is grounded, and the sacrificial anode 10 and the electronic anode 20 are insulated and installed inside the inner liner 1.

[0075] Figure 2This is a circuit diagram of another anti-corrosion device for the inner liner provided by the present invention. This embodiment is an alternative to the switching unit in the previous embodiment. The switching unit 50 can also be a single-pole double-throw (SPDT). The first fixed contact of the SPDT is connected to the second terminal of the first current sampling unit 30, the second fixed contact of the SPDT is connected to the second terminal of the variable voltage output unit 40, the common contact of the SPDT is connected to the inner liner 1, and the control terminal of the SPDT is connected to the controller 60. The parts that are the same as those in the previous embodiment will not be described again here.

[0076] In some embodiments of the present invention, such as Figure 1 , 2 As shown, the inner liner corrosion protection device also includes a second current sampling unit 70, which is connected in series with the variable voltage output unit 40 and connected to the controller 60. The second current sampling unit 70 is used to collect the current signal in the second circuit. The second current sampling unit 70 can be a conventional AD sampling circuit, which collects continuous current signals (analog signals) and converts them into discrete digital signals.

[0077] In some embodiments of the present invention, such as Figure 1 , 2 As shown, a protective resistor R1 is also connected in series in the first circuit. The protective resistor R1 is used to limit the current in the first circuit.

[0078] In some embodiments of the present invention, such as Figure 1 , 2 As shown, an indicator light L1 is also connected in series in the second circuit. Indicator light L1 can be an LED indicator light. When the second circuit is conducting, indicator light L1 is lit. Indicator light L1 can be used to indicate whether there is a fault in the second circuit where the electronic anode 20 is located. For example, when indicator light L1 can be lit, it means that the second circuit is working normally and the electronic anode 20 is working normally; when indicator light L1 cannot be lit, it means that there may be a fault in the second circuit and the electronic anode 20 cannot work normally.

[0079] In the above embodiments, the components of the inner tank anti-corrosion device, other than the sacrificial anode and the electronic anode, can be integrated into the electrical control board of the electric water heater.

[0080] Figure 3The flowchart illustrates a method for controlling corrosion prevention of the inner liner provided by this invention. Applied to the corrosion prevention device for the inner liner provided in the foregoing embodiments of this invention, this embodiment can extend the service life of the sacrificial anode, improve the accuracy of the current on the electron anode, thereby enhancing the corrosion prevention effect while reducing corrosion prevention costs. This method can be executed by the corrosion prevention control device for the inner liner provided by this invention. This device can be implemented by software and / or hardware, and is typically configured in electronic equipment, such as a controller in the corrosion prevention device for the inner liner. Figure 1 As shown, the method for the inner liner corrosion protection device includes the following steps:

[0081] S101. Send a first control signal to the switching unit. The first control signal is used to turn on the first circuit and turn off the second circuit.

[0082] In this embodiment of the invention, the controller sends a first control signal to the switching unit. This first control signal is used to turn on the first circuit and turn off the second circuit. Because the potential of the sacrificial anode is more negative than that of the inner liner, and because the sacrificial anode and the inner liner are in the same electrolyte (water in the inner liner), the sacrificial anode preferentially undergoes an oxidation reaction, releasing magnesium ions and electrons. The magnesium ions are released into the electrolyte, while the electrons are transferred to the inner liner through the first circuit. In other words, the sacrificial anode takes the place of the protected inner liner in the oxidation reaction, thus replacing the protected inner liner in the corrosion process and achieving the purpose of corrosion protection for the inner liner.

[0083] For example, refer to Figure 1 The controller 60 sends a first control signal to the switch unit 50, causing the first control switch SW1 to close, the first circuit to be connected, and the second control switch SW2 to open, the second circuit to be disconnected.

[0084] For example, refer to Figure 2 The controller 60 sends a first control signal to the switching unit 50, causing the blade of the single-pole double-throw switch (SPDT) to contact the first fixed contact, thus connecting the first circuit and disconnecting the second circuit.

[0085] S102. During the first circuit conduction period, receive the sampling current signal output by the first current sampling unit, and determine the first current based on the sampling current signal.

[0086] During the conduction of the first loop, the first current sampling unit acquires the current signal of the first loop and transmits the sampled current signal to the controller. The controller receives the sampled current signal output by the first current sampling unit and determines the first current in the first loop based on the sampled current signal.

[0087] S103. Send a second control signal to the switching unit. The second control signal is used to disconnect the first circuit and connect the second circuit.

[0088] In this embodiment of the invention, the controller sends a second control signal to the switching unit. The second control signal is used to disconnect the first circuit and turn on the second circuit.

[0089] For example, refer to Figure 1 The controller 60 sends a second control signal to the switch unit 50, causing the first control switch SW1 to open, the first circuit to be disconnected, and the second control switch SW2 to close, the second circuit to be connected.

[0090] For example, refer to Figure 2 The controller 60 sends a second control signal to the switching unit 50, causing the blade of the single-pole double-throw switch (SPDT) to contact the second fixed contact, thus disconnecting the first circuit and connecting the second circuit.

[0091] S104. A third control signal is sent to the variable voltage output unit. The third control signal is used to adjust the output voltage of the variable voltage output unit and generate a second current in the second circuit that is the same as the first current.

[0092] The controller sends a second control signal to the switching unit, and a third control signal to the variable voltage output unit. This third control signal adjusts the output voltage of the variable voltage output unit, generating a second current in the second circuit that is identical to the first current. It should be noted that the identical first and second currents in this invention mean that their directions are the same, and the error in their current values ​​is within a preset range. This means that the identical directions of the first and second currents both flow towards the inner liner. Under the voltage output by the variable voltage output unit, the electron anode transfers electrons to the protected inner liner through the second circuit, achieving the purpose of corrosion protection. Since the second current is obtained by referring to the first current of the sacrificial anode, interference from electrode polarization, water properties, and scaling in the inner liner can be effectively avoided, thereby improving the corrosion protection effect. Furthermore, since no reference electrode is required, the cost of corrosion protection is reduced. In addition, in actual use, the sacrificial anode does not need to operate continuously, thus extending its service life.

[0093] Figure 4 This is a flowchart of another method for controlling corrosion of the inner liner provided by the present invention. This embodiment is described in further detail based on the foregoing embodiments, such as... Figure 4 As shown, the corrosion control method for the inner liner includes the following steps:

[0094] S201. Send a first control signal to the switching unit. The first control signal is used to turn on the first circuit and turn off the second circuit, and maintain it for a first preset time.

[0095] In this embodiment of the invention, the first circuit is turned on, and the sacrificial anode preferentially undergoes an oxidation reaction, releasing magnesium ions and electrons. The magnesium ions are released into the electrolyte, while the electrons are transferred to the inner liner through the first circuit, achieving the purpose of corrosion protection for the inner liner. The first circuit is turned on and maintained for a first preset duration, ensuring a relatively stable current in the first circuit, which is beneficial for improving the corrosion protection effect.

[0096] For example, refer to Figure 1 The controller 60 sends a first control signal to the switch unit 50, causing the first control switch SW1 to close, the first circuit to be connected, and the second control switch SW2 to open, the second circuit to be disconnected.

[0097] For example, refer to Figure 2 The controller 60 sends a first control signal to the switching unit 50, causing the blade of the single-pole double-throw switch (SPDT) to contact the first fixed contact, thus connecting the first circuit and disconnecting the second circuit.

[0098] S202. During the first circuit conduction period, the sampling current signal output by the first current sampling unit is received, and the average value of the sampling current corresponding to the sampling current signal within the first preset time period is calculated as the first current.

[0099] During the conduction period of the first circuit, the first current sampling unit acquires the current signal of the first circuit and transmits the sampled current signal to the controller. The controller receives the sampled current signal output by the first current sampling unit and calculates the average value of the sampled current corresponding to the sampled current signal within a first preset time period as the first current. This embodiment effectively avoids the influence of current fluctuations in the first circuit on the sampled current by calculating the average value of the sampled current corresponding to the sampled current signal within a first preset time period as the first current in the first circuit, thereby improving the accuracy of the first current.

[0100] S203. Send a second control signal to the switching unit. The second control signal is used to disconnect the first circuit and connect the second circuit.

[0101] In this embodiment of the invention, the controller sends a second control signal to the switching unit. The second control signal is used to disconnect the first circuit and turn on the second circuit.

[0102] For example, refer to Figure 1 The controller 60 sends a second control signal to the switch unit 50, causing the first control switch SW1 to open, the first circuit to be disconnected, and the second control switch SW2 to close, the second circuit to be connected.

[0103] For example, refer to Figure 2 The controller 60 sends a second control signal to the switching unit 50, causing the blade of the single-pole double-throw switch (SPDT) to contact the second fixed contact, thus disconnecting the first circuit and connecting the second circuit.

[0104] S204. A third control signal is sent to the variable voltage output unit. The third control signal is used to adjust the output voltage of the variable voltage output unit and generate a second current in the second circuit that is the same as the first current.

[0105] The controller sends a second control signal to the switching unit, and a third control signal to the variable voltage output unit. This third control signal adjusts the output voltage of the variable voltage output unit, generating a second current in the second circuit that is identical to the first current. Under the voltage output by the variable voltage output unit, the electron anode transfers electrons to the protected inner liner through the second circuit, achieving corrosion protection for the inner liner. Since the second current is obtained by referencing the first current of the sacrificial anode, interference from electrode polarization, water properties, and scale buildup in the inner liner can be effectively avoided, thus improving the corrosion protection effect. Furthermore, the elimination of a reference electrode reduces corrosion protection costs. In addition, the sacrificial anode does not need to operate continuously during actual use, thereby extending its service life.

[0106] In some embodiments of the present invention, reference is made to Figure 1 , 2 The inner liner corrosion protection device also includes a second current sampling unit 70, which is connected in series with the variable voltage output unit and connected to the controller 60. The second current sampling unit 70 is used to collect the current signal in the second circuit.

[0107] After sending a third control signal to the variable voltage output unit, the sampled current signal output by the second current sampling unit is acquired. Based on the sampled current signal output by the second current sampling unit, the voltage output by the variable voltage output unit is adjusted to ensure that the second current in the second circuit is the same as the first current. This embodiment improves the accuracy of the voltage output by the variable voltage output unit by acquiring the current signal in the second circuit and adjusting the voltage output by the variable voltage output unit accordingly. This improves the accuracy of the second current and thus enhances the corrosion resistance of the inner liner.

[0108] S205, Cumulative conduction time of the second circuit.

[0109] While sending the second control signal to the switching unit, the conduction time of the second circuit is accumulated.

[0110] S206. Determine whether the conduction time of the second circuit has reached the second preset time.

[0111] In this embodiment of the invention, it is determined whether the conduction duration of the second circuit has reached a second preset duration. The second preset duration is longer than the first preset duration, thus reducing the operating time of the sacrificial anode and extending its service life. For example, in a specific embodiment of the invention, the first preset duration can be 2 minutes, and the second preset duration can be 2 hours. If the conduction duration of the second circuit reaches the second preset duration, step S207 is executed; if the conduction duration of the second circuit has not yet reached the second preset duration, the process returns to the step of accumulating the conduction duration of the second circuit.

[0112] S207. Complete the control operation for the current round.

[0113] If the conduction time of the second circuit reaches the second preset time, the control operation of the current round is completed, and the process returns to the step of sending the first control signal to the switching unit to enter the next round of control operation, until the water heater shutdown signal is received. Here, a round of control operation refers to the control process from the issuance of the first control signal to the time period from when the conduction time of the second circuit reaches the second preset time.

[0114] This embodiment controls the alternating conduction of the first and second circuits, with the conduction duration of the second circuit being longer than that of the first circuit. On the one hand, this avoids the sacrificial anode from working for an extended period, thus extending its service life. On the other hand, it updates the magnitude of the first current, effectively avoiding the influence of water temperature and other factors, ensuring that the potential of the protected inner tank remains within the specified range, thereby improving the corrosion resistance.

[0115] In some embodiments of the present invention, the liner corrosion control method further includes:

[0116] 1. If the sampling current signal output by the first current sampling unit is not received after the first control signal is sent to the switching unit, it is determined that the sacrificial anode installation is faulty or the switching unit is faulty.

[0117] For example, refer to Figure 1 The first control switch SW1 can be a normally closed switch, and the second control switch SW2 can be a normally open switch. That is, when the controller 60 is not working, the first control switch SW1 is closed, the first circuit is connected, and the second control switch SW2 disconnects the second circuit, allowing the sacrificial anode 10 to operate. In the event of a prolonged power outage in the water heater, the sacrificial anode 10 will preferentially undergo an oxidation reaction, replacing the corroded inner tank and achieving the purpose of corrosion protection for the inner tank. After sending the first control signal to the switch unit 50, if no sampling current signal is received from the first current sampling unit 30 (i.e., the first circuit is not connected), it is determined that either the sacrificial anode 10 is faulty or the first control switch SW1 is faulty.

[0118] For example, refer to Figure 2 The first fixed contact of the single-pole double-throw (SPDT) switch is normally closed, and the second fixed contact is normally open. When the controller 60 is not operating, the blade of the SPDT switch is in contact with the first fixed contact, the first circuit is connected, the second circuit is disconnected, and the sacrificial anode 10 operates. In cases of prolonged power outages in the water heater, the sacrificial anode 10 preferentially undergoes an oxidation reaction, replacing the corroded inner tank and thus achieving corrosion protection. After sending the first control signal to the switch unit 50, if no sampling current signal is received from the first current sampling unit 30 (i.e., the first circuit is not connected), it is determined that either the sacrificial anode 10 is faulty or the SPDT switch is faulty.

[0119] 2. If the sampling current signal output by the second current sampling unit is not received after the second control signal is sent to the switching unit, it is determined that the electronic anode installation is faulty or the switching unit is faulty.

[0120] For example, refer to Figure 1 If the sampling current signal output by the second current sampling unit 70 is not received after the second control signal is sent to the switching unit 50, it is determined that the electronic anode 20 is faulty or the second control switch SW2 is faulty.

[0121] For example, refer to Figure 2 If the sampling current signal output by the second current sampling unit 70 is not received after the second control signal is sent to the switching unit 50, it is determined that the electronic anode 20 is faulty or the single-pole double-throw switch SPDT is faulty.

[0122] 3. If the sampling current signals output by the first current sampling unit and the second current sampling unit are received simultaneously, it is determined that the switching unit has malfunctioned.

[0123] For example, refer to Figure 1 If the first current sampling unit 30 and the second current sampling unit 70 are received simultaneously, it is determined that the first control switch SW1 is faulty. After the second control switch SW2 is closed, the first control switch SW1 (normally closed switch) cannot be opened normally. At this time, the controller 60 can send a first control signal to open the second control switch SW2, that is, the electronic anode 20 stops working and switches to the sacrificial anode 10, and issue a fault alarm to remind the user to contact the manufacturer for on-site repair.

[0124] In some embodiments of the present invention, the inner wall of the inner liner is enamel-lined. The enamel isolates water from the inner wall of the liner, thus protecting it. When the enamel is damaged, the previously protected inner wall of the liner is exposed at the damaged area. The more severe the damage, the larger the exposed area, resulting in a lower total resistance in the first circuit. Under the same conditions, the first current in the first circuit will be greater than when the enamel is intact. Therefore, the present invention can determine the integrity of the enamel based on the magnitude of the first current.

[0125] For example, in an embodiment of the present invention, after determining the first current based on the sampled current signal, the method further includes:

[0126] The range of the first current is determined. If the first current is less than or equal to a first preset value, the enamel on the inner wall of the inner liner is considered intact. If the first current is greater than the first preset value but less than or equal to a second preset value, the enamel on the inner wall of the inner liner is considered to have minor damage, and a repair mode is entered until the first current is less than or equal to the first preset value. In the repair mode, the conduction time of the first circuit is greater than that of the second circuit, allowing the sacrificial anode to fully release metal ions (e.g., magnesium ions). Utilizing the polarity of the inner wall of the inner liner to attract positively charged metal ions, the metal ions are adsorbed at the damaged enamel, forming an insulating precipitate to repair the damaged area of ​​the inner liner enamel. For example, in the repair mode, the conduction time of the first circuit is 2 hours, and the conduction time of the second circuit is 1 hour. If the first current is greater than the second preset value, the enamel on the inner wall of the inner liner is considered to have significant damage, exceeding the repair capacity of the sacrificial anode, and a maintenance reminder signal can be issued to remind the user to inspect or maintain it. The first and second preset values ​​can be obtained through analysis of a large amount of historical data.

[0127] When the entire unit is under prolonged power outage or the water quality in the inner tank is poor (high conductivity), the sacrificial anode will be consumed rapidly. After the sacrificial anode is consumed to a certain extent, the first current in the first circuit will decrease sharply and cannot reflect the actual current required to protect the inner tank. At this time, the sacrificial anode will also be unable to play a protective role. Therefore, in some embodiments of the present invention, the inner tank corrosion prevention control method may further include:

[0128] 1. Each time the electric water heater is turned on, or according to a preset cycle, determine whether the current first current is less than the current threshold. The current threshold represents the minimum current value at which the sacrificial anode needs to be replaced.

[0129] 2. If so, a second control signal is sent to the switching unit to disconnect the first circuit and connect the second circuit. The sacrificial anode stops working and the electronic anode starts working. At the same time, a prompt message can be sent to remind the user to replace the sacrificial anode.

[0130] 3. Obtain the current water temperature of the inner tank.

[0131] While sending a second control signal to the switching unit, the current water temperature of the inner tank can be obtained through a temperature sensor installed inside the inner tank.

[0132] 4. Based on the mapping relationship between current and water temperature, the third current required for the second circuit under the current water temperature condition is obtained.

[0133] For example, under the same conditions, the higher the water temperature, the greater the conductivity of the water, and the greater the corresponding initial current. Therefore, a mapping relationship between current and water temperature can be established in advance based on historical data.

[0134] In some embodiments of the present invention, the process of establishing the mapping relationship between current and water temperature is as follows:

[0135] Within a set time period after the electric water heater is initially turned on, multiple water temperatures and the corresponding first current for each water temperature are acquired. Initial turn-on refers to the first time the electric water heater is turned on. The multiple water temperatures are divided into multiple temperature ranges, and the corresponding first current for each temperature range is determined. A mapping table between the first current and the temperature ranges is constructed as the mapping relationship between current and water temperature. For example, within the range of 5℃ to 85℃, the temperature is divided into multiple temperature ranges at 10℃ intervals, and the current value corresponding to each temperature range is determined based on historical data, forming a mapping table between the first current and the temperature ranges as the mapping relationship between current and water temperature. For example, the current value corresponding to each temperature range can be the average of the current values ​​corresponding to all temperatures within that temperature range in the historical data; this invention does not impose such a limitation.

[0136] In other embodiments of the present invention, the process of establishing the mapping relationship between current and water temperature is as follows:

[0137] Within a set time period after the electric water heater is initially turned on, multiple water temperatures and the corresponding first current for each water temperature are acquired, dividing the multiple water temperatures into multiple temperature ranges. For each temperature range, based on the first current corresponding to the endpoint temperature of the range, a linear function relationship between the current and the water temperature is constructed as a mapping relationship between the current and the water temperature. For example, within the range of 5℃ to 85℃, the temperature is divided into multiple temperature ranges at 10℃ intervals, and the current value corresponding to each temperature range is determined based on historical data. For each temperature range, based on the first current corresponding to the endpoint temperature of the range, a linear function relationship between the current and the water temperature is constructed as a mapping relationship between the current and the water temperature. For example, a linear interpolation method can be used to construct the linear function relationship between the current and the water temperature; this invention is not limited to this method.

[0138] In some embodiments of the present invention, the mapping relationship between current and water temperature for each temperature range is as follows:

[0139]

[0140] in, The current water temperature, The third current required for the second circuit under the current water temperature conditions. The maximum temperature within the temperature range. This represents the minimum temperature within the temperature range. This is the first current corresponding to the maximum temperature within the temperature range. This is the first current corresponding to the minimum temperature within the temperature range.

[0141] After obtaining the current water temperature of the inner tank, a third current required for the second circuit under the current water temperature condition is obtained based on a pre-established mapping relationship between current and water temperature. For example, in one embodiment, after obtaining the current water temperature of the inner tank, a target temperature range is determined, and the current corresponding to the target temperature range is looked up from the mapping relationship table as the third current required for the second circuit under the current water temperature condition. In another embodiment, after obtaining the current water temperature of the inner tank, a target temperature range is determined, and the current water temperature is substituted into the mapping relationship corresponding to the target temperature range to calculate the third current required for the second circuit under the current water temperature condition.

[0142] 5. Send a fourth control signal to the variable voltage output unit. The fourth control signal is used to adjust the output voltage of the variable voltage output unit and generate a fourth current in the second circuit that is the same as the third current.

[0143] In this embodiment of the invention, after calculating the third current required for the second circuit under the current water temperature conditions, a fourth control signal is sent to the variable voltage output unit. The fourth control signal is used to adjust the output voltage of the variable voltage output unit, generating a fourth current in the second circuit that is the same as the third current. It should be noted that, in this invention, the third current and the fourth current being the same means that the directions of the third current and the fourth current are the same, and the error between their current values ​​is within a preset range.

[0144] Because the first current in the first circuit decreases sharply after the sacrificial anode is consumed to a certain extent, it cannot reflect the actual current required to protect the inner tank, leading to a decline in the protective effect of the electronic anode. Therefore, this embodiment of the invention utilizes the mapping relationship between current and water temperature to calculate the third current required for the second circuit under the current water temperature condition, and sends a fourth control signal to the variable voltage output unit. The fourth control signal is used to adjust the output voltage of the variable voltage output unit to generate a fourth current in the second circuit that is the same as the third current. Since the third current is based on the current water temperature, rather than the current in the first circuit after the sacrificial anode has been largely consumed, it is closer to the actual current required to protect the inner tank than the current in the first circuit after the sacrificial anode has been largely consumed. Therefore, it can ensure that the potential of the protected inner tank is within the specified range, improving the anti-corrosion effect.

[0145] It should be noted that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0146] This invention also provides an electric water heater, which includes a controller for executing the inner tank anti-corrosion control method provided in any of the foregoing embodiments of this invention. For example, the controller may be a microcontroller.

[0147] Figure 5 This is a schematic diagram of the structure of an anti-corrosion control device for an inner liner provided by the present invention, as shown below. Figure 5 As shown, the inner liner corrosion prevention control device is used to execute the inner liner corrosion prevention control method provided in any of the foregoing embodiments of the present invention. The inner liner corrosion prevention control device includes:

[0148] The first control module 101 is used to send a first control signal to the switching unit, the first control signal being used to turn on the first circuit and turn off the second circuit.

[0149] The receiving and determining module 102 is used to receive the sampling current signal output by the first current sampling unit during the conduction period of the first circuit, and determine the first current based on the sampling current signal;

[0150] The second control module 103 is used to send a second control signal to the switching unit. The second control signal is used to control the first circuit to disconnect and to make the second circuit to conduct.

[0151] The third control module 104 is used to send a third control signal to the variable voltage output unit. The third control signal is used to adjust the output voltage of the variable voltage output unit and generate a second current in the second circuit that is the same as the first current.

[0152] In some embodiments of the present invention, the first control signal is used to control the first circuit to be turned on for a first preset duration, and the first current is the average value of the sampling current corresponding to the sampling current signal within the first preset duration.

[0153] In some embodiments of the present invention, the inner liner corrosion prevention control device further includes:

[0154] The duration accumulation module is used to accumulate the conduction duration of the second circuit after sending a third control signal to the variable voltage output unit;

[0155] The duration determination module is used to determine whether the conduction duration of the second circuit reaches a second preset duration, wherein the second preset duration is longer than the first preset duration;

[0156] The first return module is used to complete the control operation of the current round when the conduction time of the second circuit reaches the second preset time, and return to the step of sending the first control signal to the switch unit to enter the next round of control operation until the electric water heater is turned off.

[0157] The second return module is used to return to the step of accumulating the conduction time of the second circuit when the conduction time of the second circuit has not reached the second preset time.

[0158] In some embodiments of the present invention, the inner liner anti-corrosion device further includes a second current sampling unit, which is connected in series with the variable voltage output unit and connected to the controller. The inner liner anti-corrosion control device further includes:

[0159] The sampling current signal acquisition module is used to acquire the sampling current signal output by the second current sampling unit after sending a third control signal to the variable voltage output unit;

[0160] The feedback adjustment module is used to adjust the voltage output by the variable voltage output unit based on the sampled current signal output by the second current sampling unit, so that the second current in the second circuit is the same as the first current.

[0161] In some embodiments of the present invention, the inner liner corrosion prevention control device further includes:

[0162] The first fault determination module is used to determine that the sacrificial anode installation or the switching unit has malfunctioned if it does not receive the sampling current signal output by the first current sampling unit after sending a first control signal to the switching unit.

[0163] The second fault determination module is used to determine whether the electronic anode installation or the switching unit has malfunctioned if it does not receive the sampling current signal output by the second current sampling unit after sending the second control signal to the switching unit.

[0164] The third fault determination module is used to determine that the switching unit has malfunctioned when it simultaneously receives the sampled current signals output by the first current sampling unit and the second current sampling unit.

[0165] In some embodiments of the present invention, the inner wall of the inner liner is provided with enamel, and the inner liner anti-corrosion control device further includes:

[0166] The first determination module is used to determine that the enamel on the inner wall of the inner liner is intact if the first current is less than or equal to a first preset value after determining the first current based on the sampled current signal.

[0167] The second determination module is used to determine that the enamel on the inner wall of the inner liner has a minor breakage when the first current is greater than the first preset value and less than or equal to the second preset value, and to enter the repair mode until the first current is less than or equal to the first preset value; in the repair mode, the conduction time of the first circuit is greater than the conduction time of the second circuit.

[0168] The third determination module is used to determine that the enamel on the inner wall of the inner liner has suffered significant damage when the first current is greater than the second preset value, and to output a maintenance prompt signal.

[0169] In some embodiments of the present invention, the inner liner corrosion prevention control device further includes:

[0170] The current judgment module is used to determine whether the current first current is less than the current threshold each time the electric water heater is turned on, or according to a preset cycle. The current threshold represents the minimum current value at which the sacrificial anode needs to be replaced.

[0171] The fourth control module is used to send a second control signal to the switching unit when the current first current is less than the current threshold, and to send a prompt message to remind the user to replace the sacrificial anode.

[0172] A water temperature acquisition module is used to acquire the current water temperature of the inner tank;

[0173] The third current determination module is used to obtain the third current required by the second circuit under the current water temperature condition based on the mapping relationship between current and water temperature.

[0174] The fifth control module is used to send a fourth control signal to the variable voltage output unit. The fourth control signal is used to adjust the output voltage of the variable voltage output unit and generate a fourth current in the second circuit that is the same as the third current.

[0175] In some embodiments of the present invention, the inner liner corrosion prevention control device further includes:

[0176] The first data acquisition module is used to acquire multiple water temperatures and a first current corresponding to each water temperature within a set time period after the electric water heater is initially turned on.

[0177] The interval current determination module is used to divide multiple water temperatures into multiple temperature intervals and determine the first current corresponding to each temperature interval.

[0178] The relationship table construction module is used to construct a mapping relationship table between the first current and the temperature range as a mapping relationship between current and water temperature;

[0179] The third current determination module includes:

[0180] The first target range determination submodule is used to determine the target temperature range in which the current water temperature falls;

[0181] The lookup table submodule is used to find the current corresponding to the target temperature range from the mapping table as the third current required by the second circuit under the current water temperature condition.

[0182] In some embodiments of the present invention, the inner liner corrosion prevention control device further includes:

[0183] The second data acquisition module is used to acquire multiple water temperatures and a first current corresponding to each water temperature within a set time period after the electric water heater is initially turned on.

[0184] The interval division module is used to divide multiple water temperatures into multiple temperature intervals;

[0185] The interval function relationship determination module is used to construct a linear function relationship between current and water temperature as a mapping relationship between current and water temperature based on the first current corresponding to the endpoint temperature of each temperature interval for each temperature interval.

[0186] The third current determination module includes:

[0187] The second target range determination submodule is used to determine the target temperature range in which the current water temperature falls;

[0188] The current calculation submodule is used to substitute the current water temperature into the mapping relationship corresponding to the target temperature range, and calculate the third current required by the second circuit under the current water temperature condition.

[0189] In some embodiments of the present invention, the mapping relationship between current and water temperature within the temperature range is as follows:

[0190]

[0191] in, The current water temperature, The third current required by the second circuit under the current water temperature conditions. This refers to the maximum temperature within the specified temperature range. This refers to the minimum temperature within the specified temperature range. The first current corresponding to the maximum temperature within the stated temperature range. The first current corresponds to the minimum temperature within the temperature range.

[0192] The above-mentioned inner liner corrosion prevention control device can execute the inner liner corrosion prevention control method provided in any embodiment of this application, and has the corresponding functional modules and beneficial effects for executing the inner liner corrosion prevention control method.

[0193] It should be noted that the module division in the various liner corrosion prevention control devices provided in the above embodiments is illustrative and only represents a logical functional division. In actual implementation, other division methods may also be used. Furthermore, the functional modules in the various embodiments of this invention can be integrated into a single processor, exist as separate physical entities, or be integrated into a single module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0194] If the integrated module is implemented as a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the technical solution of the embodiments of the present invention can be embodied in the form of a computer program product, which is stored in a computer storage medium and includes several instructions to cause an electronic device or processor to execute all or part of the steps of the methods in the various embodiments of the present invention. The aforementioned computer storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0195] Furthermore, the inner liner corrosion prevention control device and the inner liner corrosion prevention control method provided in the above embodiments belong to the same concept, and their specific implementation process can be found in the method embodiments, which will not be repeated here.

[0196] Figure 6 This is a schematic diagram of the structure of an electronic device provided by the present invention, such as... Figure 6 As shown, the electronic device in this embodiment of the invention includes: a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps in the above-described embodiment of the inner liner corrosion prevention control method. Alternatively, when the processor executes the computer program, it implements the functions of each module in the above-described embodiment of the inner liner corrosion prevention control device.

[0197] For example, the computer program may be divided into one or more modules, which are stored in the memory and executed by the processor to complete this application. The one or more modules may be a series of computer program instruction segments capable of performing a specific function, which can be used to describe the execution process of the computer program in the electronic device.

[0198] The electronic device may be a desktop computer, a cloud server, or other computing device. The electronic device may include, but is not limited to, a processor and memory. Those skilled in the art will understand that... Figure 6 This is merely one example of an electronic device and does not constitute a limitation on the electronic device. It may include more or fewer components than illustrated, or combine certain components, or different components. For example, the electronic device may also include input / output devices, network access devices, buses, etc.

[0199] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor.

[0200] The memory can be an internal storage unit of the electronic device, such as a hard drive or RAM. Alternatively, it can be an external storage device, such as a plug-in hard drive, Smart Media Card (SMC), Secure Digital (SD) card, Flash Card, etc. Furthermore, the memory can include both internal and external storage units. The memory is used to store the computer program and other programs and data required by the electronic device. The memory can also be used to temporarily store data that has been output or will be output.

[0201] This invention also discloses an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the liner corrosion prevention control method as described in the foregoing embodiments.

[0202] This invention also discloses a computer-readable storage medium storing a computer program that, when executed by a processor, implements the liner corrosion prevention control method as described in the foregoing embodiments.

[0203] This invention also discloses a computer program product that, when run on a computer, causes the computer to execute the liner corrosion prevention control method described in the foregoing embodiments.

[0204] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0205] The specific embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method for controlling corrosion of an inner liner, characterized in that, An anti-corrosion device for an inner liner is provided, comprising a sacrificial anode, an electronic anode, a first current sampling unit, a variable voltage output unit, a switching unit, and a controller. The sacrificial anode and the electronic anode are disposed within the inner liner. A first terminal of the first current sampling unit is connected to the sacrificial anode, and a second terminal of the first current sampling unit is connected to the inner liner, forming a first circuit. A first terminal of the variable voltage output unit is connected to the electronic anode, and a second terminal of the variable voltage output unit is connected to the inner liner, forming a second circuit. The switching unit controls the connection and disconnection of the first and second circuits. The controller is connected to the first current sampling unit, the switching unit, and the variable voltage output unit, respectively. The method includes: A first control signal is sent to the switching unit, the first control signal being used to turn on the first circuit and turn off the second circuit; During the conduction of the first circuit, the sampled current signal output by the first current sampling unit is received, and the first current is determined based on the sampled current signal; A second control signal is sent to the switching unit, the second control signal being used to disconnect the first circuit and connect the second circuit; A third control signal is sent to the variable voltage output unit to adjust the output voltage of the variable voltage output unit and generate a second current in the second circuit that is the same as the first current.

2. The method for controlling corrosion of the inner liner according to claim 1, characterized in that, The first control signal is used to control the first circuit to be turned on for a first preset duration, and the first current is the average value of the sampled current corresponding to the sampled current signal within the first preset duration.

3. The method for controlling corrosion of the inner liner according to claim 2, characterized in that, After sending a third control signal to the variable voltage output unit, the method further includes: The on-time of the second circuit is accumulated; Determine whether the conduction duration of the second circuit reaches a second preset duration, wherein the second preset duration is longer than the first preset duration; If so, the current round of control operation is completed, and the process returns to the step of sending the first control signal to the switch unit to enter the next round of control operation until the electric water heater is turned off. If not, return to the step of accumulating the conduction time of the second circuit.

4. The method for controlling corrosion of the inner liner according to any one of claims 1-3, characterized in that, The inner liner anti-corrosion device further includes a second current sampling unit, which is connected in series with the variable voltage output unit and connected to the controller. After sending a third control signal to the variable voltage output unit, it also includes: Obtain the sampled current signal output by the second current sampling unit; The voltage output by the variable voltage output unit is adjusted by feedback based on the sampled current signal output by the second current sampling unit, so that the second current in the second circuit is the same as the first current.

5. The method for controlling corrosion of the inner liner according to claim 4, characterized in that, Also includes: If the sampling current signal output by the first current sampling unit is not received after the first control signal is sent to the switching unit, it is determined that the sacrificial anode installation is faulty or the switching unit is faulty. If the sampling current signal output by the second current sampling unit is not received after the second control signal is sent to the switching unit, it is determined that the electronic anode installation is faulty or the switching unit is faulty. If the sampling current signals output by the first current sampling unit and the second current sampling unit are received simultaneously, it is determined that the switching unit has malfunctioned.

6. The method for controlling corrosion of the inner liner according to any one of claims 1-3, characterized in that, The inner wall of the inner liner is enamel-lined, and after determining the first current based on the sampled current signal, the method further includes: If the first current is less than or equal to the first preset value, then the enamel on the inner wall of the inner liner is determined to be intact. If the first current is greater than the first preset value and less than or equal to the second preset value, it is determined that the enamel on the inner wall of the inner liner has a minor damage and enters the repair mode until the first current is less than or equal to the first preset value; in the repair mode, the conduction time of the first circuit is greater than the conduction time of the second circuit. If the first current is greater than the second preset value, it is determined that the enamel on the inner wall of the inner liner has suffered significant damage, and a maintenance prompt signal is output.

7. The method for controlling corrosion of the inner liner according to any one of claims 1-3, characterized in that, Also includes: Each time the electric water heater is turned on, or according to a preset cycle, it is determined whether the current first current is less than the current threshold, which represents the minimum current value at which the sacrificial anode needs to be replaced. If so, a second control signal is sent to the switching unit, along with a prompt message to remind the user to replace the sacrificial anode; Obtain the current water temperature of the inner tank; Based on the mapping relationship between current and water temperature, the third current required by the second circuit under the current water temperature condition is obtained; A fourth control signal is sent to the variable voltage output unit, which is used to adjust the output voltage of the variable voltage output unit and generate a fourth current in the second circuit that is the same as the third current.

8. The method for controlling corrosion of the inner liner according to claim 7, characterized in that, Also includes: During a set period after the electric water heater is initially turned on, multiple water temperatures and a first current corresponding to each water temperature are acquired. The multiple water temperatures are divided into multiple temperature ranges, and a first current is determined for each temperature range. Construct a mapping table between the first current and the temperature range as a mapping relationship between current and water temperature; Based on the mapping relationship between current and water temperature, the third current required by the second circuit under the current water temperature condition is obtained, including: Determine the target temperature range in which the current water temperature falls; The current corresponding to the target temperature range is found from the mapping table and used as the third current required by the second circuit under the current water temperature condition.

9. The method for controlling corrosion of the inner liner according to claim 7, characterized in that, Also includes: During a set period after the electric water heater is initially turned on, multiple water temperatures and a first current corresponding to each water temperature are acquired. Divide multiple water temperatures into multiple temperature ranges; For each temperature range, based on the first current corresponding to the endpoint temperature of the temperature range, a linear functional relationship between current and water temperature is constructed as a mapping relationship between current and water temperature. Based on the mapping relationship between current and water temperature, the third current required by the second circuit under the current water temperature condition is obtained, including: Determine the target temperature range in which the current water temperature falls; Substitute the current water temperature into the mapping relationship corresponding to the target temperature range to calculate the third current required by the second circuit under the current water temperature condition.

10. The method for controlling corrosion of the inner liner according to claim 9, characterized in that, Within the specified temperature range, the mapping relationship between current and water temperature is as follows: in, The current water temperature, The third current required by the second circuit under the current water temperature conditions. This is the maximum temperature within the specified temperature range. The minimum temperature within the stated temperature range. The first current corresponding to the maximum temperature within the stated temperature range. The first current corresponds to the minimum temperature within the temperature range.

11. A liner corrosion prevention control device, characterized in that, For performing the liner corrosion control method as described in any one of claims 1-10, comprising: The first control module is used to send a first control signal to the switching unit, the first control signal being used to turn on the first circuit and turn off the second circuit; The receiving and determining module is used to receive the sampled current signal output by the first current sampling unit during the conduction of the first circuit, and determine the first current based on the sampled current signal; The second control module is used to send a second control signal to the switching unit. The second control signal is used to control the first circuit to disconnect and to make the second circuit to conduct. The third control module is used to send a third control signal to the variable voltage output unit. The third control signal is used to adjust the output voltage of the variable voltage output unit and generate a second current in the second circuit that is the same as the first current.

12. An electric water heater, characterized in that, Includes a controller for performing the liner corrosion prevention control method as described in any one of claims 1-10.

Images