An instant water heater and a rapid constant temperature control method

Abstract

This application relates to an instant water heater and a rapid constant temperature control method, comprising: an inlet, a pre-water tank, a mixing valve, an instant heating element, an outlet, a data acquisition unit, and a control unit. The inlet is connected to both the pre-water tank and the mixing valve; the pre-water tank is connected to the mixing valve; the mixing valve is connected to the instant heating element; the instant heating element is connected to the outlet; the data acquisition unit is electrically connected to the inlet, the pre-water tank, and the instant heating element, respectively, for acquiring inlet water temperature, inlet water flow rate, storage water temperature, and the operating voltage of the instant heating element; the control unit is electrically connected to both the data acquisition unit and the mixing valve, for controlling the mixing valve to adjust the flow ratio. It is understood that this application, by acquiring multi-dimensional operating condition parameters, achieves advance perception and predictive control of water usage conditions, intervenes in advance to regulate the outlet water temperature, effectively shortens the water temperature rise time during the cold start phase, and significantly improves the temperature control response speed and constant temperature stability of the instant water heater.

Description

Technical Field

[0001] This application relates to the field of water heaters, and more particularly to an instant water heater and a method for rapid constant temperature control. Background Technology

[0002] As residents' quality of life continues to improve, instant water heaters, with their outstanding advantages such as instant hot water, have been widely used in homes and various public bathing scenarios, gradually becoming the mainstream water heater category. The ability to accurately and stably control the outlet water temperature directly determines the smoothness and comfort of the bathing experience, and is a key technical indicator for evaluating the core performance of instant water heaters.

[0003] Currently, most traditional instant water heaters use a temperature control scheme based on a single outlet water temperature index. Specifically, a temperature sensor is installed at the outlet of the instant water heater to collect the outlet water temperature signal in real time and feed it back to the control module. By adjusting the output power of the heating element, a steady-state control of the outlet water temperature is achieved.

[0004] However, existing temperature control solutions rely solely on a single outlet water temperature for closed-loop feedback, resulting in a simple control logic and limited control dimensions. Furthermore, the overall temperature control response is slow due to factors such as the thermal inertia of the heating element itself, heat exchange losses in the pipeline, and the lag in the response of temperature control components. Especially during the cold start-up phase, the heating element exhibits a significant temperature rise delay, failing to quickly achieve temperature rise and stabilization, leading to large fluctuations in the outlet water temperature and making it difficult to rapidly reach the preset target water temperature. Summary of the Invention

[0005] This application provides an instant water heater and a rapid constant temperature control method, aiming to solve the technical problem that existing instant water heaters cannot quickly complete temperature rise and temperature stability during the cold start-up phase.

[0006] In a first aspect, embodiments of this application provide an instantaneous water heater, comprising: The system includes an inlet, a pre-water tank, a mixing valve, an instant heating element, an outlet, a data acquisition unit, and a control unit. One end of the inlet is connected to the inlet of the pre-water tank and the first inlet of the mixing valve, and the other end of the inlet is connected to municipal water. The pre-water tank is equipped with a target heating element, which is used to heat the municipal water flowing into the pre-water tank. The pre-water tank is used to store the heated municipal water. The outlet of the pre-water tank is connected to the second inlet of the mixing valve. The outlet of the mixing valve is connected to the inlet of the instant heating element. The mixing valve is used to adjust the flow ratio of the municipal water flowing into the first inlet and the heated municipal water flowing into the second inlet. The water outlet of the instant heating element is connected to the water outlet. The data acquisition unit is electrically connected to the water inlet, the pre-water tank, and the instant heating element, respectively, and is used to acquire the water inlet temperature, the water inlet flow rate, the water storage temperature of the pre-water tank, and the operating voltage of the instant heating element. The control unit is electrically connected to the acquisition unit and the mixing valve respectively, and is used to control the mixing valve to adjust the flow ratio according to the inlet water temperature, the inlet water flow rate, the storage water temperature of the pre-water tank and the working voltage of the instant heating element.

[0007] Secondly, embodiments of this application provide a rapid constant temperature control method, which includes: The inlet water temperature, the inlet water flow rate, the storage water temperature of the pre-water tank, and the operating voltage of the instantaneous heating element are collected. Obtain the target outlet water temperature; The target operating level of the instantaneous heating element is determined based on the inlet water flow rate, the operating voltage, the inlet water temperature, and the target outlet water temperature. The temperature stabilization time of the instant heating element is determined based on the target operating level and the inlet water flow rate. The initial working position of the mixing valve is determined based on the target outlet water temperature, the inlet water temperature, and the storage water temperature. The instant heating element is activated according to the target working level, and the mixing valve is simultaneously adjusted to the initial working position. During the temperature stabilization period, the actual working position of the mixing valve is periodically adjusted according to the temperature change curve of the instantaneous heating element, so that the difference between the actual outlet water temperature and the target outlet water temperature is within the range of a first preset accuracy threshold.

[0008] Optionally, the instant heating element is configured with multiple operating levels, including the target operating level. Determining the target operating level of the instant heating element based on the inlet water flow rate, the operating voltage, the inlet water temperature, and the target outlet water temperature includes: Calculate the stable temperature rise value corresponding to each working level of the instantaneous heating element based on the inlet water flow rate and the working voltage; The target operating level is determined based on the stable temperature rise value corresponding to each operating level of the instantaneous heating element, the inlet water temperature, and the target outlet water temperature.

[0009] Optionally, determining the target operating level based on the stable temperature rise value corresponding to each operating level of the instantaneous heating element, the inlet water temperature, and the target outlet water temperature includes: The sum of the stable temperature rise value corresponding to each working position of the instant heating element and the inlet water temperature is calculated to obtain m temperature values, where m is an integer greater than or equal to 1. From the plurality of temperature values, select the temperature values ​​that are lower than the target outlet water temperature to obtain j temperature values, where j is an integer greater than or equal to 1 and j is less than or equal to m; Select the target temperature value from the j temperature values; The operating setting of the instant heating element corresponding to the target temperature value is taken as the target operating setting.

[0010] Optionally, selecting a target temperature value from the j temperature values ​​includes: The target temperature value is obtained by selecting the temperature value with the smallest difference from the target outlet water temperature from the j temperature values.

[0011] Optionally, determining the temperature stabilization time of the instantaneous heating element based on the target operating level and the inlet water flow rate includes: Based on the target operating level and the inlet water flow rate, the temperature stabilization time of the instant heating element is found from the preset mapping relationship. The preset mapping relationship includes multiple sets of target data and multiple temperature stabilization times. The multiple sets of target data correspond one-to-one with the multiple temperature stabilization times. Each set of target data includes the operating level of the instant heating element and the inlet water flow rate.

[0012] Optionally, determining the initial operating position of the mixing valve based on the target outlet water temperature, the inlet water temperature, and the storage water temperature includes: Calculate the hot and cold water flow ratio of the mixing valve based on the target outlet water temperature, the inlet water temperature, and the storage water temperature; The initial operating position of the mixing valve is determined based on the hot and cold water flow ratio.

[0013] Optionally, before collecting the inlet water temperature, the inlet water flow rate, the pre-tank water temperature, and the operating voltage of the instantaneous heating element, the method further includes: When water is flowing through the inlet, the inlet flow rate is collected; Determine whether the influent flow rate is greater than a preset flow rate threshold; If the inlet water flow rate is greater than the preset water flow rate threshold, then the steps of collecting the inlet water temperature, the inlet water flow rate, the storage water temperature of the pre-water tank, and the operating voltage of the instantaneous heating element are executed.

[0014] Optionally, during the temperature stabilization time, the actual operating position of the mixing valve is periodically adjusted according to the temperature change curve of the instantaneous heating element, so that the difference between the actual outlet water temperature and the target outlet water temperature is within a first preset accuracy threshold range. The method further includes: Obtain the temperature rise delay time of the instantaneous heating element; The water transport time of the municipal water from the mixing valve to the outlet is obtained; Calculate the time difference between the temperature rise delay time and the water transport time; After delaying the time difference, the following step is performed: within the temperature stabilization time, the actual working position of the mixing valve is periodically adjusted according to the temperature change curve of the instantaneous heating element so that the difference between the actual outlet water temperature and the target outlet water temperature is within the range of a first preset accuracy threshold.

[0015] Optionally, the method further includes: After the temperature stabilizes, a PID algorithm is used to adjust the actual working position of the mixing valve so that the difference between the actual outlet water temperature and the target outlet water temperature is within the range of a second preset accuracy threshold. The temperature allowable deviation range corresponding to the second preset accuracy threshold is smaller than the temperature allowable deviation range corresponding to the first preset accuracy threshold.

[0016] Thirdly, embodiments of this application also provide a computer-readable storage medium storing a computer program that, when executed by a processor, can implement the above-described method.

[0017] This application provides an instant water heater and a rapid constant temperature control method. It includes: an inlet, a pre-tank, a mixing valve, an instant heating element, an outlet, a data acquisition unit, and a control unit. One end of the inlet is connected to the inlet of the pre-tank and the first inlet of the mixing valve, while the other end is connected to municipal water. The pre-tank contains a target heating element for heating the municipal water flowing into it. The pre-tank stores the heated municipal water. The outlet of the pre-tank is connected to the second inlet of the mixing valve. The outlet of the mixing valve is connected to the inlet of the instant heating element, and the mixing valve regulates the flow of the instant water into the first inlet. The flow ratio of municipal water to heated municipal water flowing into the second inlet is specified. The outlet of the instant heating element is connected to the outlet. The acquisition unit is electrically connected to the inlet, the pre-tank, and the instant heating element, respectively, and is used to acquire the inlet water temperature, the inlet water flow rate, the pre-tank water temperature, and the instant heating element's operating voltage. The control unit is electrically connected to the acquisition unit and the mixing valve, respectively, and is used to control the mixing valve to adjust the flow ratio based on the inlet water temperature, the inlet water flow rate, the pre-tank water temperature, and the instant heating element's operating voltage. Therefore, this application overcomes the limitation of traditional instant water heaters that rely solely on a single outlet temperature signal for passive closed-loop regulation. By acquiring multi-dimensional operating parameters such as inlet water temperature, inlet water flow rate, pre-tank water temperature, and the instant heating element's operating voltage, it achieves advance perception and predictive control of water usage conditions. On the one hand, the pre-heating tank can preheat municipal water and store heat energy in advance. During the critical stage of cold start-up of instantaneous heating elements, when there is an inherent temperature rise delay, it provides a stable source of preheated water as heat compensation, offsetting the temperature lag caused by the thermal inertia of the heating elements and heat exchange losses in the pipeline. On the other hand, the control unit dynamically controls the mixing valve to adjust the ratio of cold and hot water flow based on multi-source real-time data, intervening in the outlet water temperature in advance to avoid large fluctuations in water temperature. It does not need to wait for the outlet water temperature feedback before passively adjusting, effectively shortening the water temperature rise time during the cold start-up stage, achieving a rapid rise in outlet water temperature and stabilizing it in the target range, significantly improving the temperature control response speed and constant temperature stability of instantaneous water heaters. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0021] Figure 1 This is a schematic diagram of the structure of an instantaneous water heater provided in an embodiment of this application; Figure 2a A flowchart illustrating a rapid constant temperature control method provided in an embodiment of this application; Figure 2b Temperature stability curves of the instantaneous heating element under different flow rates are provided in the embodiments of this application. Figure 2c This is a schematic diagram illustrating the principle of a rapid constant temperature method for an instant water heater provided in an embodiment of this application.

[0022] Explanation of reference numerals in the attached figures: 101. Water inlet; 102. Pre-water tank; 103. Mixing valve; 104. Instantaneous heating element; 105. Water outlet; 1021. Heat exchange tube; 1022. Target heating element. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, 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, 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.

[0024] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0025] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0026] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0027] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0028] As used in this specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if [described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [described condition or event] is detected," or "in response to detection of [described condition or event]."

[0029] To address the technical problem that existing instant water heaters cannot quickly achieve temperature rise and temperature stabilization during the cold start-up phase, this application provides an instant water heater that can quickly achieve temperature rise and temperature stabilization during the cold start-up phase.

[0030] Figure 1 This is a schematic diagram of an instantaneous water heater provided in an embodiment of this application. In one embodiment, the instantaneous water heater includes: The system includes an inlet 101, a pre-water tank 102, a mixing valve 103, an instant heating element 104, an outlet 105, a data acquisition unit, and a control unit. One end of the inlet 101 is connected to the inlet of the pre-water tank 102 and the first inlet of the mixing valve 103, and the other end of the inlet 101 is connected to the municipal water supply. The pre-water tank 102 is equipped with a target heating element 1022 and a heat exchange tube 1021. The target heating element 1022 and the heat exchange tube 1021 are used to heat the municipal water flowing into the pre-water tank 102. The pre-water tank 102 is used to store the heated municipal water. The outlet of the pre-water tank 102 is connected to the second inlet of the mixing valve 103. The outlet of the mixing valve 103 is connected to the inlet of the instant heating element 104. The mixing valve 103 is used to adjust the flow ratio of municipal water flowing into the first inlet and heated municipal water flowing into the second inlet. The water outlet of the instant heating element is connected to the water outlet 105; The data acquisition unit is electrically connected to the water inlet 101, the pre-water tank 102, and the instant heating element 104, respectively, and is used to collect the water inlet temperature of the water inlet 101, the water inlet flow rate of the water inlet 101, the water storage temperature of the pre-water tank 102, and the working voltage of the instant heating element 104. The control unit is electrically connected to the acquisition unit and the mixing valve 103 respectively, and is used to control the mixing valve 103 to adjust the flow ratio according to the inlet water temperature of the inlet 101, the inlet water flow rate of the inlet 101, the storage water temperature of the pre-water tank 102 and the working voltage of the instant heating element 104.

[0031] Preferably, the instantaneous heating element 104 is a cast aluminum heater.

[0032] The working principle of an instant water heater is as follows: When municipal water enters through inlet 101, it splits into two streams. One stream enters the pre-tank 102, where it is heated into hot water by the target heating element 1022. The hot water then flows into the first inlet of the mixing valve 103. The other stream flows directly into the second inlet of the mixing valve 103. Next, this embodiment collects the inlet water temperature and flow rate of inlet 101, the storage temperature of the pre-tank 102, and the operating voltage of the instantaneous heating element 104. It then controls the mixing valve 103 to adjust the flow ratio of municipal water flowing into the first inlet to heated municipal water flowing into the second inlet, thereby adjusting the outlet temperature of the mixing valve 103. This shortens the time required for the water temperature to rise during the cold start-up phase, enabling the outlet temperature to rise rapidly and stabilize within the target range, significantly improving the temperature control response speed and constant temperature stability of the instantaneous water heater.

[0033] This application provides an instantaneous water heater. It includes: an inlet, a pre-tank, a mixing valve, an instantaneous heating element, an outlet, a data acquisition unit, and a control unit. One end of the inlet is connected to the inlet of the pre-tank and the first inlet of the mixing valve, while the other end is connected to municipal water. The pre-tank contains a target heating element for heating the municipal water flowing into it. The pre-tank stores the heated municipal water. The outlet of the pre-tank is connected to the second inlet of the mixing valve. The outlet of the mixing valve is connected to the inlet of the instantaneous heating element, and the mixing valve regulates the flow of the instantaneous water into the first inlet. The flow ratio of municipal water to heated municipal water flowing into the second inlet is specified. The outlet of the instant heating element is connected to the outlet. The acquisition unit is electrically connected to the inlet, the pre-tank, and the instant heating element, respectively, and is used to acquire the inlet water temperature, the inlet water flow rate, the pre-tank water temperature, and the instant heating element's operating voltage. The control unit is electrically connected to the acquisition unit and the mixing valve, respectively, and is used to control the mixing valve to adjust the flow ratio based on the inlet water temperature, the inlet water flow rate, the pre-tank water temperature, and the instant heating element's operating voltage. Therefore, this application overcomes the limitation of traditional instant water heaters that rely solely on a single outlet temperature signal for passive closed-loop regulation. By acquiring multi-dimensional operating parameters such as inlet water temperature, inlet water flow rate, pre-tank water temperature, and the instant heating element's operating voltage, it achieves advance perception and predictive control of water usage conditions. On the one hand, the pre-heating tank can preheat municipal water and store heat energy in advance. During the critical stage of cold start-up of instantaneous heating elements, when there is an inherent temperature rise delay, it provides a stable source of preheated water as heat compensation, offsetting the temperature lag caused by the thermal inertia of the heating elements and heat exchange losses in the pipeline. On the other hand, the control unit dynamically controls the mixing valve to adjust the ratio of cold and hot water flow based on multi-source real-time data, intervening in the outlet water temperature in advance to avoid large fluctuations in water temperature. It does not need to wait for the outlet water temperature feedback before passively adjusting, effectively shortening the water temperature rise time during the cold start-up stage, achieving a rapid rise in outlet water temperature and stabilizing it in the target range, significantly improving the temperature control response speed and constant temperature stability of instantaneous water heaters.

[0034] Please see Figure 2a , Figure 2a This is a flowchart illustrating a rapid constant temperature control method provided in an embodiment of this application. In one embodiment, the method is applied to the aforementioned instantaneous water heater, and the method includes steps S201-S207.

[0035] S201. Collect the inlet water temperature, inlet water flow rate, pre-tank water temperature, and instantaneous heating element operating voltage.

[0036] S202, Obtain the target outlet water temperature.

[0037] S203. Determine the target operating level of the instantaneous heating element based on the inlet water flow rate, operating voltage, inlet water temperature, and target outlet water temperature.

[0038] In one embodiment, the instant heating element is configured with multiple operating levels, including the target operating level. S203 specifically includes the following steps: S2031-S2032.

[0039] S2031. Calculate the stable temperature rise value corresponding to each working position of the instant heating element based on the inlet water flow rate and working voltage.

[0040] The power calculation formula for instant heating elements is:

[0041] Where P is the power of the instant heating element, U is the operating voltage of the instant heating element, and R is the operating resistance of the instant heating element.

[0042] It should be noted that the resistance value of the working resistor corresponding to each working level in the instant heating element is different and known. Therefore, the power corresponding to each working level in the instant heating element can be calculated in this embodiment. Then, according to the temperature rise calculation formula of the instant heating element, the stable temperature rise corresponding to each working level is calculated. The temperature rise calculation formula is:

[0043] Where P is the power of the instantaneous heating element and Q is the inlet water flow rate.

[0044] Please see Figure 2b , Figure 2b The temperature stability curves of the instant heating element under different flow rates are provided in the embodiments of this application. It should be noted that after the instant heating element is started, its temperature rise shows a dynamic trend within a preset time t; after the preset time t is reached, the temperature rise tends to stabilize and no longer changes. In the embodiments of this application, the stable temperature rise corresponding to each working level refers to the temperature rise value of the heating element after the preset time t.

[0045] S2032. Determine the target operating level based on the stable temperature rise value, inlet water temperature, and target outlet water temperature corresponding to each operating level of the instantaneous heating element.

[0046] In one embodiment, S2032 specifically includes the following steps: S20321-S20324.

[0047] S20321. Calculate the sum of the stable temperature rise value and the inlet water temperature for each working position of the instant heating element to obtain m temperature values.

[0048] Where m is an integer greater than or equal to 1; S20322. Select the temperature values ​​that are lower than the target outlet water temperature from multiple temperature values ​​to obtain j temperature values.

[0049] Where j is an integer greater than or equal to 1, and j is less than or equal to m; S20323. Select the target temperature value from j temperature values; When j equals 1, the temperature value obtained according to S20322 is the target temperature value.

[0050] In one embodiment, S20323 specifically includes the following steps: a.

[0051] a. Select the temperature value with the smallest difference from the target outlet water temperature from the j temperature values ​​to obtain the target temperature value.

[0052] When j is greater than 1, the temperature value with the smallest difference from the target outlet water temperature is selected as the target temperature value. It should be noted that the smaller the temperature value is compared with the target outlet water temperature, the faster the outlet water temperature can be adjusted to the target outlet water temperature.

[0053] S20324. The working position of the instant heating element corresponding to the target temperature value shall be taken as the target working position.

[0054] In other words, the embodiments of this application select the most suitable working setting so that the water temperature at the outlet can quickly reach the target water temperature.

[0055] S204. Determine the temperature stabilization time of the instant heating element based on the target operating level and the inlet water flow rate.

[0056] In one embodiment, S204 specifically includes the following steps: S2041.

[0057] S2041. Based on the target operating level and water inlet flow rate, find the temperature stabilization time of the instant heating element from the preset mapping relationship.

[0058] The preset mapping relationship includes multiple sets of target data and multiple temperature stabilization times. The multiple sets of target data correspond one-to-one with the multiple temperature stabilization times. Each set of target data includes the working level of the instant heating element and the inlet water flow rate.

[0059] Please see Figure 2b The temperature stabilization time of an instant heating element refers to the time required for the instant heating element to reach a stable temperature from startup. For example, the horizontal axis corresponding to the red dots in each temperature curve represents the temperature stabilization time of the instant heating element under the corresponding inlet water flow conditions.

[0060] It should be noted that the preset mapping relationship was obtained based on practical experience. This application does not impose any limitations on it. Furthermore, this application stores the preset mapping relationship in the storage unit of the instantaneous water heater.

[0061] S205. Determine the initial working position of the mixing valve based on the target outlet water temperature, inlet water temperature, and storage water temperature.

[0062] In one embodiment, S205 specifically includes the following steps: S2051-S2052.

[0063] S2051. Calculate the hot and cold water flow ratio of the mixing valve based on the target outlet water temperature, inlet water temperature, and storage water temperature.

[0064] The formula for calculating the hot and cold water flow ratio of a mixing valve is:

[0065] in, For water storage temperature, For the target outlet water temperature, The inlet water temperature, This is the stable temperature rise value corresponding to the instant heating element when it is operating at the target working level.

[0066] S2052. Determine the initial working position of the mixing valve based on the ratio of hot and cold water flow rates.

[0067] It should be noted that, in this embodiment, a stepper motor is used to control the rotation of the mixing valve based on the hot and cold water flow ratio, so that the mixing valve rotates to its initial working position. Furthermore, based on practical experience, this application can obtain a mapping relationship between the hot and cold water flow ratio and the working position of the mixing valve. By finding this mapping relationship based on the hot and cold water flow ratio, the initial working position of the mixing valve can be determined.

[0068] S206. Start the instant heating element according to the target working level, and simultaneously adjust the mixing valve to the initial working position.

[0069] It should be noted that the embodiments of this application simultaneously perform the steps of "starting the instant heating element according to the target working level" and "adjusting the mixing valve to the initial working position" so that the outlet water temperature can quickly reach the target outlet water temperature.

[0070] S207. During the temperature stabilization period, the actual working position of the mixing valve is periodically adjusted according to the temperature change curve of the instantaneous heating element so that the difference between the actual outlet water temperature and the target outlet water temperature is within the first preset accuracy threshold range.

[0071] It should be noted that S201-S207 can enable the actual water temperature at the outlet to quickly approach the target water temperature.

[0072] Please see Figure 2c , Figure 2c This is a schematic diagram illustrating the principle of a rapid temperature-regulating method for an instantaneous water heater, provided in an embodiment of this application. Figure 2c The mixing water temperature is the outlet water temperature of the mixing valve. During the temperature stabilization period, the temperature of the instantaneous heating element (cast aluminum heater) rises. To ensure that the temperature of the instantaneous heating element plus the mixing water temperature equals the target outlet water temperature, the mixing water temperature needs to be dynamically reduced. Therefore, the actual operating position of the mixing valve needs to be dynamically adjusted to dynamically reduce the mixing water temperature. Specifically, in the embodiments of this application, the actual operating position of the mixing valve can be periodically adjusted according to the mixing water temperature.

[0073] This application provides a rapid constant temperature control method, applied to the instantaneous water heater of the above embodiment. The method includes: collecting the inlet water temperature, the inlet water flow rate, the storage water temperature of the pre-water tank, and the operating voltage of the instantaneous heating element; obtaining the target outlet water temperature; determining the target operating level of the instantaneous heating element based on the inlet water flow rate, the operating voltage, the inlet water temperature, and the target outlet water temperature; determining the temperature stabilization time of the instantaneous heating element based on the target operating level and the inlet water flow rate; determining the initial operating position of the mixing valve based on the target outlet water temperature, the inlet water temperature, and the storage water temperature; starting the instantaneous heating element according to the target operating level, and simultaneously adjusting the mixing valve to the initial operating position; during the temperature stabilization time, periodically adjusting the actual operating position of the mixing valve according to the temperature change curve of the instantaneous heating element, so that the difference between the actual outlet water temperature and the target outlet water temperature is within a first preset accuracy threshold range. Therefore, the rapid constant temperature control method of this application breaks through the limitation of traditional instant water heaters that rely solely on a single temperature signal from the water outlet for passive closed-loop regulation. The logic behind its beneficial effects is as follows: First, by simultaneously collecting multi-dimensional operating parameters such as inlet water temperature, inlet water flow rate, pre-tank water temperature, and instant heating element operating voltage, it eliminates the dependence of traditional control methods on single outlet water temperature feedback, realizing advance perception and predictive regulation of water usage conditions. This lays a data foundation for subsequent precise temperature control and avoids the drawbacks of "passive feedback and delayed regulation" from the source. Secondly, the pre-tank is not simply a water storage unit; it preheats municipal water and stores heat energy to specifically address the inherent temperature rise delay issue during cold start-up of instantaneous heating elements. In the initial startup phase, the temperature rise of an instantaneous heating element is dynamically changing and cannot immediately reach a stable heating state. The stable preheated water source provided by the pre-tank directly compensates for this, effectively offsetting the temperature rise lag caused by the heating element's thermal inertia and pipeline heat exchange losses, thus shortening the water temperature rise cycle during cold start-up. Finally, based on collected multi-source real-time data, the control unit accurately determines the target operating level of the instantaneous heating element, ensuring it starts up in optimal condition and quickly stabilizes. Simultaneously, it determines the initial operating position of the mixing valve and periodically adjusts its actual operating position according to the temperature change curve before the heating element reaches a stable temperature, dynamically distributing the cold and hot water flow rates. This proactive intervention in the outlet water temperature prevents significant temperature fluctuations.In summary, this application effectively solves the pain points of slow temperature control response and large temperature fluctuations during cold start of traditional instant water heaters through the collaborative control logic of "multi-parameter prediction + pre-heat source compensation + dynamic synchronous adjustment". It significantly improves the temperature control response speed and constant temperature stability of instant water heaters, and further optimizes the user's water experience.

[0074] In one embodiment, prior to S201, the method further includes S208-S210.

[0075] S208. When water is flowing through the inlet, the inlet flow rate is collected.

[0076] S209. Determine whether the inlet flow rate is greater than the preset flow rate threshold.

[0077] S210. If the inlet flow rate is greater than the preset flow rate threshold, then execute S201.

[0078] It should be noted that S208-S210 will be explained in detail below.

[0079] When the inlet water flow rate is too low, directly turning on the instant heating element can easily lead to dry burning. Therefore, it is necessary to determine the inlet water flow rate in advance. Additionally, the inlet water flow rate fluctuates significantly when water is first introduced; therefore, the inlet water flow rate should only be collected after a first preset time delay following the initial water flow. Preferably, the first preset time is 3 seconds.

[0080] Preferably, the water flow rate threshold is set to 2.0 L / min. S201 is executed only when the inflow rate is greater than the preset water flow rate threshold. When the inflow rate is less than or equal to the preset water flow rate threshold, the process returns to execute S208.

[0081] In one embodiment, prior to S207, the method further includes S211-S214.

[0082] S211. Obtain the temperature rise delay time of the instantaneous heating element.

[0083] The temperature rise delay time is the duration during which the temperature rise remains at 0 when the instantaneous heating element starts working. For example... Figure 2c It can be seen that the temperature rise delay time of the instant heating element is approximately 5 seconds.

[0084] S212. Obtain the water transfer time from the municipal water mixing valve to the outlet.

[0085] In this embodiment, the water transport time from the mixing valve to the outlet can be calculated based on the pipeline volume between the mixing valve and the outlet and the water flow velocity of the mixing valve.

[0086] S213. Calculate the time difference between the temperature rise delay time and the water transport time. S214. After the time difference is calculated, execute S207 as described above.

[0087] It should be noted that the temperature of the water flowing out of the outlet changes only after the time difference between the delayed temperature rise time and the water transmission time has elapsed, and only then can S207 be executed.

[0088] In one embodiment, the method further includes: S215.

[0089] S215. After the temperature stabilizes, the actual working position of the mixing valve is adjusted using a PID algorithm so that the difference between the actual outlet water temperature and the target outlet water temperature is within the range of the second preset accuracy threshold.

[0090] The temperature tolerance range corresponding to the second preset accuracy threshold is smaller than the temperature tolerance range corresponding to the first preset accuracy threshold. In other words, when the outlet water temperature is close to the target outlet water temperature, the PID algorithm is used to adjust the actual working position of the mixing valve to improve the accuracy of the outlet water temperature.

[0091] It will be understood by those skilled in the art that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program may be stored in a storage medium, which is a computer-readable storage medium. The computer program is executed by at least one processor in the computer system to implement the process steps of the embodiments of the above methods.

[0092] Therefore, embodiments of this application also provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the rapid constant temperature control method provided in any of the foregoing method embodiments.

[0093] The storage medium is a physical, non-transient storage medium, such as a USB flash drive, external hard drive, read-only memory (ROM), magnetic disk, or optical disk, or any other physical storage medium capable of storing program code. The computer-readable storage medium can be non-volatile or volatile.

[0094] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this application.

[0095] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of each unit is merely a logical functional division, and there may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

[0096] The steps in the methods of this application embodiment can be adjusted, merged, or deleted according to actual needs. The units in the apparatus of this application embodiment can be merged, divided, or deleted according to actual needs. Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0097] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a terminal, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0098] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0099] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Since these modifications and variations fall within the scope of the claims and their equivalents, this application also intends to include these modifications and variations.

[0100] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An instantaneous water heater, characterized in that, include: The system includes an inlet, a pre-water tank, a mixing valve, an instant heating element, an outlet, a data acquisition unit, and a control unit. One end of the inlet is connected to the inlet of the pre-water tank and the first inlet of the mixing valve, and the other end of the inlet is connected to municipal water. The pre-water tank is equipped with a target heating element, which is used to heat the municipal water flowing into the pre-water tank. The pre-water tank is used to store the heated municipal water. The outlet of the pre-water tank is connected to the second inlet of the mixing valve. The outlet of the mixing valve is connected to the inlet of the instant heating element. The mixing valve is used to adjust the flow ratio of the municipal water flowing into the first inlet and the heated municipal water flowing into the second inlet. The water outlet of the instant heating element is connected to the water outlet. The data acquisition unit is electrically connected to the water inlet, the pre-water tank, and the instant heating element, respectively, and is used to acquire the water inlet temperature, the water inlet flow rate, the water storage temperature of the pre-water tank, and the operating voltage of the instant heating element. The control unit is electrically connected to the acquisition unit and the mixing valve respectively, and is used to control the mixing valve to adjust the flow ratio according to the inlet water temperature, the inlet water flow rate, the storage water temperature of the pre-water tank and the working voltage of the instant heating element.

2. A rapid constant temperature control method, characterized in that, The method is applied to the instantaneous water heater as described in claim 1, and the method includes: The inlet water temperature, the inlet water flow rate, the storage water temperature of the pre-water tank, and the operating voltage of the instantaneous heating element are collected. Obtain the target outlet water temperature; The target operating level of the instantaneous heating element is determined based on the inlet water flow rate, the operating voltage, the inlet water temperature, and the target outlet water temperature. The temperature stabilization time of the instant heating element is determined based on the target operating level and the inlet water flow rate. The initial working position of the mixing valve is determined based on the target outlet water temperature, the inlet water temperature, and the storage water temperature. The instant heating element is activated according to the target working level, and the mixing valve is simultaneously adjusted to the initial working position. During the temperature stabilization period, the actual working position of the mixing valve is periodically adjusted according to the temperature change curve of the instantaneous heating element, so that the difference between the actual outlet water temperature and the target outlet water temperature is within the range of a first preset accuracy threshold.

3. The method according to claim 2, characterized in that, The instantaneous heating element is configured with multiple operating levels, including the target operating level. Determining the target operating level of the instantaneous heating element based on the inlet water flow rate, the operating voltage, the inlet water temperature, and the target outlet water temperature includes: Calculate the stable temperature rise value corresponding to each working level of the instantaneous heating element based on the inlet water flow rate and the working voltage; The target operating level is determined based on the stable temperature rise value corresponding to each operating level of the instantaneous heating element, the inlet water temperature, and the target outlet water temperature.

4. The method according to claim 3, characterized in that, The step of determining the target operating level based on the stable temperature rise value corresponding to each operating level of the instantaneous heating element, the inlet water temperature, and the target outlet water temperature includes: The sum of the stable temperature rise value corresponding to each working position of the instant heating element and the inlet water temperature is calculated to obtain m temperature values, where m is an integer greater than or equal to 1. From the plurality of temperature values, select the temperature values ​​that are lower than the target outlet water temperature to obtain j temperature values, where j is an integer greater than or equal to 1 and j is less than or equal to m; Select the target temperature value from the j temperature values; The operating setting of the instant heating element corresponding to the target temperature value is taken as the target operating setting.

5. The method according to claim 4, characterized in that, The step of selecting a target temperature value from the j temperature values ​​includes: The target temperature value is obtained by selecting the temperature value with the smallest difference from the target outlet water temperature from the j temperature values.

6. The method according to claim 2, characterized in that, The step of determining the temperature stabilization time of the instantaneous heating element based on the target operating level and the inlet water flow rate includes: Based on the target operating level and the inlet water flow rate, the temperature stabilization time of the instant heating element is found from the preset mapping relationship. The preset mapping relationship includes multiple sets of target data and multiple temperature stabilization times. The multiple sets of target data correspond one-to-one with the multiple temperature stabilization times. Each set of target data includes the operating level of the instant heating element and the inlet water flow rate.

7. The method according to claim 2, characterized in that, Determining the initial operating position of the mixing valve based on the target outlet water temperature, the inlet water temperature, and the storage water temperature includes: Calculate the hot and cold water flow ratio of the mixing valve based on the target outlet water temperature, the inlet water temperature, and the storage water temperature; The initial operating position of the mixing valve is determined based on the hot and cold water flow ratio.

8. The method according to any one of claims 2 to 7, characterized in that, Before collecting the inlet water temperature, the inlet water flow rate, the pre-water tank storage temperature, and the operating voltage of the instantaneous heating element, the method further includes: When water is flowing through the inlet, the inlet flow rate is collected; Determine whether the influent flow rate is greater than a preset flow rate threshold; If the inlet water flow rate is greater than the preset water flow rate threshold, then the steps of collecting the inlet water temperature, the inlet water flow rate, the storage water temperature of the pre-water tank, and the operating voltage of the instantaneous heating element are executed.

9. The method according to any one of claims 2 to 7, characterized in that, During the temperature stabilization time, based on the temperature change curve of the instantaneous heating element, the actual working position of the mixing valve is periodically adjusted so that the difference between the actual outlet water temperature and the target outlet water temperature is within a first preset accuracy threshold range. The method further includes: Obtain the temperature rise delay time of the instantaneous heating element; The water transport time of the municipal water from the mixing valve to the outlet is obtained; Calculate the time difference between the temperature rise delay time and the water transport time; After delaying the time difference, the following step is performed: within the temperature stabilization time, the actual working position of the mixing valve is periodically adjusted according to the temperature change curve of the instantaneous heating element so that the difference between the actual outlet water temperature and the target outlet water temperature is within the range of a first preset accuracy threshold.

10. The method according to any one of claims 2 to 7, characterized in that, The method further includes: After the temperature stabilizes, a PID algorithm is used to adjust the actual working position of the mixing valve so that the difference between the actual outlet water temperature and the target outlet water temperature is within the range of a second preset accuracy threshold. The temperature allowable deviation range corresponding to the second preset accuracy threshold is smaller than the temperature allowable deviation range corresponding to the first preset accuracy threshold.

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