Control method of water dispenser and water dispenser

Abstract

The invention relates to the technical field of water dispensers, in particular to a control method of a water dispenser and the water dispenser. According to the control method of the water dispenser, the water dispenser comprises a water pump and a heating body which are communicated in sequence; the control method comprises the steps that the actual water inlet temperature and the target water outlet temperature of the heating body are obtained; based on the actual water inlet temperature, the target water outlet temperature and the maximum power of the heating body, the theoretical water outlet flow of the heating body is determined; the actual maximum water outlet flow of the water dispenser is obtained; according to the comparison result of the theoretical water outlet flow and the actual maximum water outlet flow, the power of the heating body and the power of the water pump are selectively adjusted through PID. Through the arrangement, the heating body and the water pump are adjusted through PID based on the actual water inlet temperature, then the influence of heating fluctuation on the water outlet temperature in the heating process of the heating body or the influence of the water supply flow speed of the water pump on the water outlet temperature is reduced, and the effect that the water outlet temperature of the heating body is constant is achieved more quickly.

Description

Technical Field

[0001] The invention relates to the technical field of water drinking machines, and specifically provides a control method for a water drinking machine and a water drinking machine. Background Art

[0002] With the improvement of living standards, people have higher and higher requirements for drinking water. Drinking water machines that can output water at precise constant temperature have become an urgent need for people in many aspects of daily life.

[0003] At present, the water outlet temperature of instant hot water dispensers is mainly controlled by adjusting the heating power of the heater. Since the heater has a lag in the heating process and is affected by the inlet water temperature and flow rate, the outlet water temperature of the heater fluctuates greatly. Therefore, it is difficult to achieve a constant outlet water temperature of the heater by simply adjusting the power of the heater, which results in a long time for the overall outlet water temperature of the water dispenser to reach a stable state, poor precise temperature control performance of the water dispenser, and unsatisfactory user experience.

[0004] Accordingly, the art requires a new control method for a water dispenser to solve the above problems. Summary of the invention

[0005] In order to solve the above problems in the prior art, that is, to solve the problem that the water outlet temperature of the existing water dispenser is unstable.

[0006] In a first aspect, the present invention provides a control method for a water dispenser, wherein the water dispenser comprises a water pump and a heating body connected in sequence; the control method comprises: obtaining an actual water inlet temperature and a target water outlet temperature of the heating body; determining a theoretical water outlet flow rate of the heating body based on the actual water inlet temperature, the target water outlet temperature and the maximum power of the heating body; obtaining an actual maximum water outlet flow rate of the water dispenser; and selectively adjusting the power of the heating body and the power of the water pump through PID according to a comparison result between the theoretical water outlet flow rate and the actual maximum water outlet flow rate.

[0007] In the case of the preferred technical scheme of the control method of the above-mentioned water dispenser, the specific steps of "selectively adjusting the power of the heating body and the power of the water pump through PID according to the comparison result of the theoretical water outlet flow rate and the actual maximum water outlet flow rate" include: setting the mapping relationship between the duty cycle of the water pump power and the water supply flow rate of the water pump; obtaining the difference between the target water outlet temperature and the actual water outlet temperature of the heating body and setting a preset threshold; if the theoretical water outlet flow rate is greater than the actual maximum water outlet flow rate, converting the theoretical water outlet flow rate into a first duty value according to the mapping relationship, and the water pump operates at the first duty value; and selectively adjusting the chopping of the power of the heating body through PID according to the comparison result of the difference and the preset threshold.

[0008] In the case of the preferred technical solution of the control method of the above-mentioned water dispenser, the specific step of "selectively adjusting the chopping of the power of the heating body through PID based on the comparison result of the difference and the preset threshold value" includes: if the difference is less than the preset threshold value, adjusting the chopping value of the power of the heating body through PID; if the difference is not less than the preset threshold value, setting the chopping value of the power of the heating body to a first default value, and the power of the heating body running at the first default value is less than the maximum power of the heating body.

[0009] In the case of the preferred technical scheme of the control method of the above-mentioned water dispenser, the specific steps of "selectively adjusting the power of the heating body and the power of the water pump through PID based on the comparison result of the theoretical water outlet flow rate and the actual maximum water outlet flow rate" include: if the theoretical water outlet flow rate is not greater than the actual maximum water outlet flow rate, the heating body operates at maximum power; and based on the comparison result of the difference and the preset threshold value, selectively adjusting the duty cycle of the water pump power through PID.

[0010] In the case of the preferred technical solution of the control method of the above-mentioned water dispenser, the specific steps of "selectively adjusting the duty cycle of the water pump power through PID based on the comparison result of the difference and the preset threshold value" include: converting the actual water flow rate into a second duty value according to the mapping relationship, and the water pump operates at the second duty value; if the difference is less than the preset threshold value, adjusting the duty cycle of the water pump power through PID; if the difference is not less than the preset threshold value, reducing the duty cycle of the water pump power and making it less than the second duty value.

[0011] In the case of the preferred technical solution of the control method of the water dispenser, the specific calculation formula of "determining the theoretical water outlet flow rate of the heating body based on the actual water inlet temperature, the target water outlet temperature and the maximum power of the heating body" is: F = (P max ×η) / [C×(T obj -T in )]; where F is the theoretical water flow rate, P max is the maximum power of the heating body, η is the heat conversion efficiency of the heating body, C is the specific heat capacity of water, T obj is the target outlet water temperature, T in is the actual inlet water temperature.

[0012] In the case of the preferred technical solution of the control method of the above-mentioned water dispenser, the water dispenser also includes a heat exchanger and an intelligent mixing valve, the two ends of the cold water flow channel of the heat exchanger are respectively connected to the water pump and the water inlet end of the heating body, the two ends of the hot water flow channel of the heat exchanger are respectively connected to the water inlet end of the intelligent mixing valve and the water outlet end of the heating body, and the water inlet end of the intelligent mixing valve is also connected to the water outlet end of the heating body; wherein the target water outlet temperature is set to the boiling point temperature of water.

[0013] In the case of the preferred technical scheme of the control method of the above-mentioned water dispenser, the control method also includes: setting the target mixed water outlet temperature of the intelligent regulating valve; establishing a corresponding relationship between the target mixed water outlet temperature from low to high and the opening of the intelligent mixing valve from small to large, and adjusting the intelligent mixing valve to the opening step corresponding to the target mixed water outlet temperature based on the corresponding relationship; obtaining the actual mixed water outlet temperature of the intelligent regulating valve; and selectively adjusting the opening of the intelligent mixing valve through PID according to the comparison result of the target mixed water outlet temperature and the actual mixed water outlet temperature.

[0014] In the case of the preferred technical scheme of the control method of the above-mentioned water dispenser, the specific steps of "selectively adjusting the opening of the intelligent mixing valve through PID according to the comparison result of the actual mixed water outlet temperature and the target mixed water outlet temperature" include: if the actual mixed water outlet temperature is lower than the target mixed water outlet temperature, increasing the number of opening steps of the intelligent mixing valve through PID adjustment; if the number of opening steps of the intelligent mixing valve increases to a maximum value, stopping PID adjustment of the opening of the intelligent mixing valve; if the actual mixed water outlet temperature is higher than the target mixed water outlet temperature, reducing the number of opening steps of the intelligent mixing valve through PID adjustment; if the number of opening steps of the intelligent mixing valve decreases to a minimum value, stopping PID adjustment of the opening of the intelligent mixing valve; if the actual mixed water outlet temperature is equal to the target mixed water outlet temperature, maintaining the opening of the intelligent mixing valve unchanged.

[0015] In a second aspect, the present invention further provides a water dispenser, comprising a control module, wherein the control module is configured to execute the control method of the water dispenser.

[0016] It can be understood by those skilled in the art that the control method of the water dispenser of the present invention comprises a water pump and a heating body connected in sequence; the control method comprises: obtaining the actual water inlet temperature and the target water outlet temperature of the heating body; determining the theoretical water outlet flow rate of the heating body based on the actual water inlet temperature, the target water outlet temperature and the maximum power of the heating body; obtaining the actual maximum water outlet flow rate of the water dispenser; and selectively adjusting the power of the heating body and the power of the water pump through PID according to the comparison result between the theoretical water outlet flow rate and the actual maximum water outlet flow rate. Through such a setting, the heating body and the water pump are respectively adjusted through PID based on the actual water inlet temperature, thereby reducing the influence of heating fluctuations on the water outlet temperature during the heating process of the heating body or reducing the influence of the water supply flow rate of the water pump on the water outlet temperature, and achieving the effect of constant water temperature of the heating body outlet more quickly.

[0017] Further, the specific steps of "selectively adjusting the power of the heating body and the power of the water pump through PID according to the comparison result between the theoretical water flow rate and the actual maximum water flow rate" include: setting the mapping relationship between the duty cycle of the power of the water pump and the water supply flow rate of the water pump; obtaining the difference between the target water outlet temperature and the actual water outlet temperature of the heating body and setting a preset threshold; if the theoretical water flow rate is greater than the actual maximum water flow rate, the theoretical water flow rate is converted into a first duty value according to the mapping relationship, and the water pump operates at the first duty value; and according to the comparison result between the difference and the preset threshold, selectively adjusting the chopping of the power of the heating body through PID. If the difference is less than the preset threshold, the chopping value of the power of the heating body is adjusted through PID; if the difference is not less than the preset threshold, the chopping value of the power of the heating body is set to the first default value, and the power of the heating body running at the first default value is less than the maximum power of the heating body. If the theoretical water flow rate is not greater than the actual maximum water flow rate, the heating body operates at the maximum power; and according to the comparison result between the difference and the preset threshold, selectively adjusting the duty cycle of the power of the water pump through PID. According to the mapping relationship, the actual water flow rate is converted into the second duty value, and the water pump operates at the second duty value; if the difference is less than the preset threshold, the duty cycle of the water pump power is adjusted by PID; if the difference is not less than the preset threshold, the duty cycle of the water pump power is reduced and is less than the second duty value. Through such a setting, when the water inlet temperature of the heating body is high, when the heating body heats up and approaches the target water outlet temperature, the PID is used to accurately control the temperature of the heating body to avoid temperature fluctuations of the heating body at the target water outlet temperature; when the water inlet temperature of the heating body is low, when the heating body heats up and approaches the target water outlet temperature, the PID is used to accurately control the flow of the water pump to avoid temperature fluctuations caused by the water supply of the water pump, thereby improving the heating body under different water inlet temperature conditions, and PID adjustment is performed on the heating body and the water pump to achieve a constant temperature water outlet state for the heating body.

[0018] Furthermore, the control method also includes: setting a target mixed water outlet temperature of the intelligent regulating valve; establishing a corresponding relationship between the target mixed water outlet temperature from low to high and the opening of the intelligent mixing valve from small to large, and adjusting the intelligent mixing valve to the opening step corresponding to the target mixed water outlet temperature based on the corresponding relationship; obtaining the actual mixed water outlet temperature of the intelligent regulating valve; and selectively adjusting the opening of the intelligent mixing valve through PID according to the comparison result between the target mixed water outlet temperature and the actual mixed water outlet temperature. If the actual mixed water outlet temperature is less than the target mixed water outlet temperature, the opening step of the intelligent mixing valve is increased through PID adjustment; if the opening step of the intelligent mixing valve increases to a maximum value, the PID adjustment of the opening of the intelligent mixing valve is stopped; if the actual mixed water outlet temperature is greater than the target mixed water outlet temperature, the opening step of the intelligent mixing valve is reduced through PID adjustment; if the opening step of the intelligent mixing valve is reduced to a minimum value, the PID adjustment of the opening of the intelligent mixing valve is stopped; if the actual mixed water outlet temperature is equal to the target mixed water outlet temperature, the opening of the intelligent mixing valve is maintained unchanged. Through such a setting, the opening of the intelligent mixing valve is adjusted with the help of PID to avoid the temperature fluctuation of the intelligent mixing valve's muddy water temperature control and reduce the temperature fluctuation of the intelligent mixing valve's temperature-controlled outlet water.

[0019] In addition, the water dispenser further provided by the present invention on the basis of the above-mentioned technical solution has the technical effects possessed by the above-mentioned control method of the water dispenser because it adopts the above-mentioned control method of the water dispenser. Compared with the existing water dispenser, the water outlet temperature of the water dispenser of the present invention is more balanced and stable, thereby improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings, in which:

[0021] Figure 1 It is a schematic diagram of the water circuit structure of the first preferred embodiment of the water dispenser of the present invention;

[0022] Figure 2 Schematic diagram of the water circuit structure of the second preferred embodiment of the water dispenser of the present invention;

[0023] Figure 3 It is a flow chart of the main steps of the control method of the water dispenser of the present invention;

[0024] Figure 4 It is a detailed step flow chart of the control method of the water dispenser of the present invention.

[0025] List of reference numerals:

[0026] 1. Heat exchanger; 2. Heating body; 3. Water pump; 4. Intelligent mixing valve; 5. Water inlet solenoid valve; 6. Faucet; 71. First temperature sensor; 72. Second temperature sensor; 73. Third temperature sensor; 8. Flow meter. DETAILED DESCRIPTION

[0027] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0028] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. In addition, the terms "first", "second" and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0029] Based on the background technology, the changes in the water inlet temperature and water inlet flow rate of the heating body of the water dispenser are very likely to cause the fluctuation of the water outlet temperature of the heating body, thereby causing the problem of unstable water outlet temperature of the water dispenser. The present invention is based on the actual water inlet temperature of the heating body, the target water outlet temperature, the theoretical water outlet flow rate and the actual maximum water outlet flow rate of the water dispenser, and uses PID to adjust the heating body and the water pump in sections, thereby reducing the influence of the changes in the water inlet temperature and water inlet flow rate of the heating body on the water outlet temperature of the heating body, so that the water dispenser can achieve the effect of constant temperature water outlet faster.

[0030] Specifically, Figure 1 As shown, in a preferred embodiment of the water dispenser, the water dispenser includes a water pump 3, a heating body 2 and a faucet 6 which are connected in sequence. Among them, a water inlet solenoid valve 5 is provided on the pipeline connecting the water inlet end of the water pump 3 to the clean water source, and a flow meter 8 is provided on the pipeline between the water pump 3 and the heating body 2. A first temperature sensor 71 for detecting the water inlet temperature of the heating body 2 and a second temperature sensor 72 for detecting the water outlet temperature are respectively provided at both ends of the heating body 2. The water dispenser also includes a control module, and the water inlet solenoid valve 5, the water pump 3, the heating body 2, the first temperature sensor 71 and the second temperature sensor 72 are evenly connected to the control module for communication.

[0031] like Figure 3 As shown, the main steps of the water dispenser control method of the present invention include:

[0032] S1, obtaining the actual water inlet temperature and target water outlet temperature of the heating body 2;

[0033] S2, determining the theoretical water outlet flow rate of the heating body 2 based on the actual water inlet temperature, the target water outlet temperature and the maximum power of the heating body 2;

[0034] S3, obtaining the actual maximum water flow rate of the water dispenser;

[0035] S4. According to the comparison result between the theoretical water outlet flow rate and the actual maximum water outlet flow rate, the power of the heating body 2 and the power of the water pump 3 are selectively adjusted through PID.

[0036] It should be noted that the specific calculation formula (1) of the theoretical water outlet flow rate of the heating body 2 is: F=(P max ×η) / [C×(T obj -T in )];

[0037] Among them, F is the theoretical water flow rate, P max is the maximum power of the heating body 2, η is the heat conversion efficiency of the heating body 2, C is the specific heat capacity of water, T obj is the target outlet water temperature, T in is the actual inlet water temperature.

[0038] For example, the P of the heating element 2 is set to max The actual maximum water flow rate of the water dispenser system is set to 0.8L / min by default, and the water volume C is 4.2*10 3 J / Kg·℃.

[0039] Among them, under the condition that the maximum power of the heating body 2, the heat conversion efficiency of the heating body 2 and the specific heat capacity of water are all constant fixed values, the heating body 2 operates at the maximum power. If the difference between the target water outlet temperature of the heating body 2 and the actual water inlet temperature is larger, the water flow in the heating body 2 is small and the flow rate is slow, which is more conducive to extending the heating time of the water flow in the heating body 2. In this state, the heating body 2 first heats the inlet water quickly and then adjusts the water supply flow of the water pump 3 through PID to facilitate faster and more accurate temperature control of the outlet water.

[0040] If the difference between the target outlet water temperature of the heating body 2 and the actual inlet water temperature is smaller, the water flow in the heating body 2 is large and the flow rate is fast, thus avoiding overheating of the water flow. In this state, maintaining the existing water supply flow rate of the water pump 3 and adjusting the heating body 2 through PID can more quickly and accurately control the outlet water temperature.

[0041] Therefore, the theoretical water flow rate calculated according to the formula is compared with the actual maximum water flow rate of the water dispenser system by default, and the working modes of the water pump 3 and the heating body 2 are adjusted by PID according to different scenarios so as to quickly and accurately ensure the balance of the water outlet temperature.

[0042] It should be noted that the default actual maximum water flow rate of the water dispenser system is restricted and affected by structures such as the water pump 3, pipelines, solenoid valves on the pipelines, and faucets 6. Water dispensers with different water channel structures have different actual maximum water flow rates.

[0043] The specific process of the control method of the present invention is described in detail below in conjunction with two embodiments.

[0044] Embodiment 1

[0045] Preferably, Figure 4 As shown, in step S4, the detailed steps of the water dispenser control method of the present invention include:

[0046] S40, setting a mapping relationship between the duty cycle of the power of the water pump 3 and the water supply flow rate of the water pump 3;

[0047] S41, obtaining the difference between the target water outlet temperature and the actual water outlet temperature of the heating body 2 and setting a preset threshold;

[0048] S421. If the theoretical water flow rate is greater than the actual maximum water flow rate, the theoretical water flow rate is converted into a first duty value according to the mapping relationship, and the water pump 3 operates at the first duty value; and based on the comparison result between the difference and the preset threshold, the power chopping of the heating body 2 is selectively adjusted through PID.

[0049] S4211, if the difference is less than the preset threshold, the chopping value of the power of the heating body 2 is adjusted by PID;

[0050] S4212: If the difference is not less than the preset threshold, the chopping value of the power of the heating body 2 is set to a first default value, and the power of the heating body 2 running at the first default value is less than the maximum power of the heating body 2.

[0051] Exemplarily, the linear mapping relationship between the duty cycle of the power of the water pump 3 and the water supply flow of the water pump 3 is set to V=A×D+B, where D is the duty cycle of the power of the water pump 3, and the value of A is set to 0.8 and the value of B is set to 0.1. The target outlet water temperature is set to 70°C, and the preset threshold is 5. The heating body 2 is set to perform normal heating and temperature rise with a default chopping value of 0.9, and the heating body 2 is set to perform maximum power heating and temperature rise with a chopping value of 1.

[0052] When the numerical temperature obtained by the first temperature sensor 71 is 25°C, that is, the actual water inlet temperature of the heating body 2 is 25°C, the theoretical water outlet flow F1 of the heating body 2 is calculated to be approximately 0.9 liters / minute according to formula (1). The theoretical water outlet flow (0.9) is greater than the actual maximum water outlet (0.8) of the water dispenser system by default.

[0053] The mapping relationship formula V=A×D+B is transformed into the formula D=(VB) / A, and the first duty value of the power of the water pump 3 converted from the value of F1 is (0.9-0.1) / 0.8=100%, that is, D1=100%. The water pump 3 operates at the first duty value (100%) to supply water to the heating body 2.

[0054] During the heating process, the value of the second temperature sensor 72 is obtained in real time, that is, the actual water outlet temperature of the heating body 2. If the actual water outlet temperature is 67°C, the difference between the target water outlet temperature (70°C) and the actual water outlet temperature (67°C) of the heating body 2 is calculated to be (3); if the difference (3) is less than the preset threshold (5), the chopping value of the power of the heating body 2 is adjusted by PID.

[0055] It can be understood that, when the target water outlet temperature is set to a constant value, the actual water inlet temperature of the heating body 2 is high. When the heating body 2 is heated to a temperature close to the target water outlet temperature under the condition of the theoretical water outlet flow rate, the PID control heating method of the heating body 2 is promptly adjusted to reduce the fluctuation range of the actual water outlet temperature of the heating body 2 within the target water outlet temperature, thereby achieving the effect of constant and stable water outlet temperature of the heating body 2.

[0056] If the actual water outlet temperature is 62°C, the difference between the target water outlet temperature (70°C) and the actual water outlet temperature (62°C) of the heating body 2 is calculated to be (8), and the difference (8) is greater than the preset threshold value (5), then the heating body 2 runs heating at the first default value of 0.9.

[0057] It is understandable that when the heating body 2 has not been heated to a temperature close to the target water outlet temperature under the condition of the theoretical water outlet flow rate, the heating body 2 can be heated normally under the condition of the theoretical water outlet flow rate.

[0058] Embodiment 2

[0059] Preferably, Figure 4 As shown, in step S4, the detailed steps of the water dispenser control method of the present invention include:

[0060] S40, setting a mapping relationship between the duty cycle of the power of the water pump 3 and the water supply flow rate of the water pump 3;

[0061] S41, obtaining the difference between the target water outlet temperature and the actual water outlet temperature of the heating body 2 and setting a preset threshold;

[0062] S422: If the theoretical water flow rate is not greater than the actual maximum water flow rate, the heating body 2 operates at the maximum power; and according to the comparison result between the difference and the preset threshold, the duty cycle of the power of the water pump 3 is selectively adjusted through PID. The actual water flow rate is converted into a second duty value according to the mapping relationship, and the water pump 3 operates at the second duty value;

[0063] S4221, if the difference is less than the preset threshold, adjust the duty cycle of the power of the water pump 3 through PID;

[0064] S4222: If the difference is not less than the preset threshold, the duty cycle of the power of the water pump 3 is reduced and is less than the second duty cycle value.

[0065] Exemplarily, the mapping relationship between the duty cycle of the power of the water pump 3 and the water supply flow of the water pump 3 is set to V=A×D+B, where D is the duty cycle of the power of the water pump 3, and the value of A is set to 0.8 and the value of B is set to 0.1. The target water outlet temperature is set to 80°C, and the preset threshold is 5. The heating body 2 is set to perform normal heating and temperature rise with a default chopping value of 0.9, and the heating body 2 is set to perform maximum power heating and temperature rise with a chopping value of 1.

[0066] When the value of the first temperature sensor 71 is 15° C., the actual water inlet temperature is 15° C. According to formula (1), the theoretical water outlet flow rate F2 of the heating body 2 is calculated to be about 0.6 liters / minute, and the theoretical water outlet flow rate (0.6) is not greater than the actual maximum water outlet (0.8) of the water dispenser system by default.

[0067] Then set the heating element 2 to heat with a chopping value of 1, and

[0068] The mapping relationship formula V=A×D+B is transformed into the formula D=(VB) / A, and the F2 value is converted into the second duty value of the power of the water pump 3, which is (0.6-0.1) / 0.8=62.5%, that is, D2=62.5%. The water pump 3 operates at the second duty value (62.5%) to supply water to the heating body 2.

[0069] During the heating process, the value of the second temperature sensor 72 is obtained in real time, that is, the actual outlet water temperature of the heating body 2. If the actual outlet water temperature is 77°C, the difference between the target outlet water temperature (80°C) and the actual outlet water temperature (77°C) of the heating body 2 is calculated to be (3); if the difference (3) is less than the preset threshold (5), the duty cycle of the power of the water pump 3 is adjusted through PID.

[0070] It is understandable that, under the condition of setting the target outlet water temperature to a fixed value, when the actual water inlet temperature of the heating body 2 is low, the water pump 3 supplies water to the heating body 2 at a smaller flow rate (theoretical outlet water flow rate) so that the heating body 2 can quickly heat the water to the target outlet water temperature. Therefore, the heating body 2 works at maximum power to increase the temperature (the chopping value is 1) to shorten the heating time. When the actual outlet water temperature of the heating body 2 is close to the target outlet water temperature range, the PID control is promptly used to adjust the duty cycle of the power of the water pump 3, and the fluctuation range of the actual outlet water temperature of the heating body 2 within the target outlet water temperature is reduced by controlling the water flow entering the heating body 2, so as to achieve the effect of constant temperature stability of the outlet water of the heating body 2.

[0071] If the actual water outlet temperature of the heating body 2 is 72°C, the difference between the calculated target water outlet temperature (80°C) and the actual water outlet temperature (62°C) of the heating body 2 is (8), and the difference (8) is greater than the preset threshold value (5), then the duty cycle of the power of the water pump 3 is reduced and is less than the second duty cycle value (62.5%).

[0072] It is understandable that when the heating body 2 has not been heated to a temperature close to the target water outlet temperature under the condition of the theoretical water outlet flow rate, the duty cycle of the operating power of the water pump 3 can be reduced to further reduce the water flow so that the water flow in the heating body 2 heats up faster, saving heating time.

[0073] In summary, under the condition of setting the target water outlet temperature of the heating body 2, the water outlet can be adjusted by PID control of the heating body 2 and the water pump 3 according to the different water inlet temperatures, which can achieve faster and stable constant temperature water outlet of the heating body 2.

[0074] In addition, if Figure 2 As shown, in another preferred embodiment of the water dispenser, the water dispenser includes a water pump 3, a heating body 2, a heat exchanger 1, an intelligent regulating valve and a faucet 6 which are connected in sequence. Among them, the heat exchanger 1 includes a cold water flow channel and a hot water flow channel. The two ends of the cold water flow channel of the heat exchanger 1 are respectively connected to the outlet of the water pump 3 and the inlet of the heating body 2. The two ends of the hot water flow channel of the heat exchanger 1 are respectively connected to the water inlet end of the intelligent mixing valve 4 and the outlet of the heating body 2. The water inlet end of the intelligent mixing valve 4 is also connected to the outlet of the heating body 2. A flow meter 8 is provided between the water pump 3 and the cold water flow channel of the heat exchanger 1. When the water pump 3 drives the water flow to pass through the heating body 2 for heating and boiling, the boiled water passes through the hot water flow channel of the heat exchanger 1 and the cold water in the cold water flow channel for heat exchange and cooling to form warm water. The warm water and the boiled water are mixed through the intelligent regulating valve to modulate boiled water of different temperatures. In addition, the water dispenser also includes a control module, and the water inlet solenoid valve 5, the water pump 3, the heating body 2, the intelligent regulating valve, the first temperature sensor 71, the second temperature sensor 72 and the third temperature sensor 73 are evenly connected to the control module for communication.

[0075] Compared with the control methods in the first and second embodiments, it is only necessary to set the target outlet water temperature of the heating body 2 within the range of 95° C.-100° C. to ensure that the outlet water of the heating body 2 is in a boiling state.

[0076] The control method further includes:

[0077] Set the target mixed water outlet temperature of the intelligent regulating valve;

[0078] Establishing a corresponding relationship between the target mixed water outlet temperature from low to high and the opening degree of the intelligent mixing valve 4 from small to large, and adjusting the intelligent mixing valve 4 to the opening degree corresponding to the target mixed water outlet temperature based on the corresponding relationship;

[0079] Obtain the actual mixed water outlet temperature of the intelligent regulating valve;

[0080] According to the comparison result between the actual mixed water outlet temperature and the target mixed water outlet temperature, the opening degree of the intelligent mixing valve 4 is selectively adjusted through PID.

[0081] If the actual mixed water outlet temperature is lower than the target mixed water outlet temperature, the number of opening steps of the intelligent mixing valve 4 is increased through PID regulation; if the number of opening steps of the intelligent mixing valve 4 increases to a maximum value, the PID regulation of the opening of the intelligent mixing valve 4 is stopped;

[0082] If the actual mixed water outlet temperature is greater than the target mixed water outlet temperature, the opening steps of the intelligent mixing valve 4 are reduced through PID regulation; if the opening steps of the intelligent mixing valve 4 are reduced to a minimum value, the PID regulation of the opening of the intelligent mixing valve 4 is stopped;

[0083] If the target mixed water outlet temperature is equal to the actual mixed water outlet temperature, the opening degree of the intelligent mixing valve 4 is maintained unchanged.

[0084] That is to say, according to the relationship between the target mixed water outlet temperature and the opening degree of the intelligent mixing valve 4, the intelligent mixing valve 4 is controlled to adjust to the preset opening steps. When the inlet water temperature of the water dispenser causes the inlet water flow rate to change, the actual mixed water outlet temperature will usually deviate from the target mixed water outlet temperature. By adjusting the opening degree of the intelligent mixing valve 4 through PID, temperature fluctuations in the process of warm water and hot water temperature adjustment can be avoided, thereby achieving the effect of constant and stable outlet water temperature of the intelligent mixing valve 4.

[0085] For example, the target outlet water temperature of the heating body 2 is set to 95°C. When the opening step number of the intelligent mixing valve 4 is set to 0, the target outlet mixed water temperature of the intelligent regulating valve is 40°C; when the opening step number of the intelligent mixing valve 4 is set to 100, the target outlet mixed water temperature of the intelligent regulating valve is 95°C. That is, for every 2 steps increase in the opening step number of the intelligent mixing valve 4, the target outlet mixed water temperature increases by 1°C.

[0086] When the target mixed water outlet temperature of the intelligent regulating valve is set to 50°C, the intelligent regulating valve is adjusted to a corresponding opening step of 20.

[0087] If the value obtained from the third temperature sensor 73 (the actual mixed water outlet temperature of the intelligent regulating valve) is 48° C., the actual mixed water outlet temperature (48° C.) is less than the target mixed water outlet temperature (50° C.) and is greater than, the number of steps of the opening of the intelligent mixing valve 4 is increased from 20 to 24 through PID regulation.

[0088] It should be noted that when the target mixed water outlet temperature of the intelligent regulating valve is set to 94°C and the actual mixed water outlet temperature of the intelligent regulating valve is 92°C, the opening steps of the intelligent mixing valve 4 increase from 98 to a maximum value of 100, and the opening of the intelligent mixing valve 4 is stopped by PID.

[0089] If the value obtained from the third temperature sensor 73 (the actual mixed water outlet temperature of the intelligent regulating valve) is 52° C., the actual mixed water outlet temperature (52° C.) is greater than the target mixed water outlet temperature (50° C.), and the number of steps of the opening of the intelligent mixing valve 4 is reduced from 20 to 16 through PID regulation.

[0090] It should be noted that when the target mixed water outlet temperature of the intelligent regulating valve is set to 41°C and the actual mixed water outlet temperature of the intelligent regulating valve is 43°C, the opening steps of the intelligent mixing valve 4 are reduced from 2 to the minimum value 0, and the opening of the intelligent mixing valve 4 described in PID is stopped.

[0091] If the value obtained from the third temperature sensor 73 (the actual mixed water outlet temperature of the intelligent regulating valve) is 50° C., the actual mixed water outlet temperature (50° C.) is equal to the target mixed water outlet temperature (50° C.), and the opening step number (20) of the intelligent mixing valve 4 is maintained unchanged.

[0092] It should be noted that the control modules of the first and second embodiments of the present invention are used to execute the above-mentioned control method of the water dispenser. The control module includes a PID controller, and the parameter P value of the PID controller is obtained by the formula: P = power of the water pump 3 × (target water outlet temperature - actual water outlet temperature) / (target water outlet temperature - actual water inlet temperature).

[0093] It should be understood that since the setting of the control module is only for illustrating the functional unit of the system of the present invention, the physical device corresponding to the control module can be the processor itself, or a part of the software in the processor, a part of the hardware, or a part of the combination of software and hardware. Therefore, the number of control modules can be configured as needed. It can be understood by those skilled in the art that the control module can be adaptively split. The specific splitting of the control module will not cause the technical solution to deviate from the principle of the present invention, therefore, the technical solutions after the splitting will fall within the protection scope of the present invention.

[0094] Finally, it should be noted that the setting and selection of specific numerical values ​​of parameters such as the actual water inlet temperature of the heating body 2, the target water outlet temperature, the theoretical water outlet flow rate, the actual maximum water outlet flow rate of the water dispenser, and the chopping value of the heating body 2 in the above-mentioned embodiment are only for illustrating the operation process and principle of the control method. In actual applications, those skilled in the art can flexibly adjust the specific values ​​or numerical ranges of the above-mentioned parameters according to the specific use environment to meet actual needs.

[0095] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A method for controlling a water dispenser, characterized in that: The water dispenser comprises a water pump (3) and a heating body (2) which are connected in sequence; The control method comprises: Obtaining the actual water inlet temperature and target water outlet temperature of the heating body (2); Determining a theoretical water outlet flow rate of the heating body (2) based on the actual water inlet temperature, the target water outlet temperature and the maximum power of the heating body (2); Obtaining the actual maximum water flow rate of the water dispenser; According to the comparison result between the theoretical water outlet flow rate and the actual maximum water outlet flow rate, the power of the heating body (2) and the power of the water pump (3) are selectively adjusted through PID.

2. The control method of the water dispenser according to claim 1, characterized in that: The specific steps of "selectively adjusting the power of the heating body (2) and the power of the water pump (3) through PID according to the comparison result between the theoretical water outlet flow rate and the actual maximum water outlet flow rate" include: Setting a mapping relationship between the duty cycle of the water pump (3) power and the water supply flow rate of the water pump (3); Obtaining the difference between the target water outlet temperature and the actual water outlet temperature of the heating body (2) and setting a preset threshold; If the theoretical water output flow rate is greater than the actual maximum water output flow rate, the theoretical water output flow rate is converted into a first duty value according to the mapping relationship, and the water pump (3) operates at the first duty value; and According to the comparison result between the difference and the preset threshold value, the chopping of the power of the heating body (2) is selectively adjusted through PID.

3. The control method of the water dispenser according to claim 2, characterized in that: The specific steps of "selectively adjusting the chopping of the power of the heating body (2) by PID according to the comparison result between the difference and the preset threshold value" include: If the difference is less than the preset threshold, adjusting the chopping value of the power of the heating body (2) through PID; If the difference is not less than the preset threshold, the chopping value of the power of the heating body (2) is set to a first default value, and the power of the heating body (2) running at the first default value is less than the maximum power of the heating body (2).

4. The control method of the water dispenser according to claim 2, characterized in that: The specific steps of "selectively adjusting the power of the heating body (2) and the power of the water pump (3) through PID according to the comparison result of the theoretical water outlet flow rate and the actual maximum water outlet flow rate" include: If the theoretical water output flow rate is not greater than the actual maximum water output flow rate, the heating body (2) operates at maximum power; and According to the comparison result between the difference and the preset threshold value, the duty cycle of the power of the water pump (3) is selectively adjusted through PID.

5. The control method of the water dispenser according to claim 4, characterized in that: The specific steps of "selectively adjusting the duty cycle of the power of the water pump (3) through PID according to the comparison result between the difference and the preset threshold value" include: The actual water flow rate is converted into a second duty value according to the mapping relationship, and the water pump (3) operates at the second duty value; If the difference is less than the preset threshold, adjusting the duty cycle of the power of the water pump (3) through PID; If the difference is not less than the preset threshold, the duty cycle of the power of the water pump (3) is reduced and is less than the second duty cycle value.

6. The control method of a water dispenser according to any one of claims 1 to 5, characterized in that: The specific calculation formula for "determining the theoretical water outlet flow rate of the heating body (2) based on the actual water inlet temperature, the target water outlet temperature and the maximum power of the heating body (2)" is: F=(P max ×η) / [C×(T obj -T in )]; Wherein, F is the theoretical water flow rate, P max is the maximum power of the heating body (2), η is the heat conversion efficiency of the heating body (2), C is the specific heat capacity of water, T obj is the target outlet water temperature, T in is the actual inlet water temperature.

7. The control method of the water dispenser according to claim 6, characterized in that: The water dispenser further comprises a heat exchanger (1) and an intelligent mixing valve (4); the two ends of the cold water flow channel of the heat exchanger (1) are respectively connected to the water pump (3) and the water inlet end of the heating body (2); the two ends of the hot water flow channel of the heat exchanger (1) are respectively connected to the water inlet end of the intelligent mixing valve (4) and the water outlet end of the heating body (2); the water inlet end of the intelligent mixing valve (4) is also connected to the water outlet end of the heating body (2); wherein the target water outlet temperature is set to the boiling point of water.

8. The control method of the water dispenser according to claim 7, characterized in that: The control method further comprises: Setting a target mixed water outlet temperature of the intelligent regulating valve; Establishing a corresponding relationship between the target mixed water outlet temperature from low to high and the opening degree of the intelligent mixing valve (4) from small to large, and adjusting the intelligent mixing valve (4) to the opening degree step number corresponding to the target mixed water outlet temperature based on the corresponding relationship; Obtaining the actual mixed water outlet temperature of the intelligent regulating valve; According to the comparison result between the actual mixed water outlet temperature and the target mixed water outlet temperature, the opening degree of the intelligent mixing valve (4) is selectively adjusted through PID.

9. The control method of the water dispenser according to claim 8, characterized in that: The specific steps of "selectively adjusting the opening of the intelligent mixing valve (4) through PID according to the comparison result between the actual mixed water outlet temperature and the target mixed water outlet temperature" include: If the actual mixed water outlet temperature is lower than the target mixed water outlet temperature, the number of opening steps of the intelligent mixing valve (4) is increased through PID regulation; if the number of opening steps of the intelligent mixing valve (4) increases to a maximum value, the PID regulation of the opening of the intelligent mixing valve (4) is stopped; If the actual mixed water outlet temperature is greater than the target mixed water outlet temperature, the number of steps of the opening of the intelligent mixing valve (4) is reduced through PID regulation; if the number of steps of the opening of the intelligent mixing valve (4) is reduced to a minimum value, the PID regulation of the opening of the intelligent mixing valve (4) is stopped; If the actual mixed water outlet temperature is equal to the target mixed water outlet temperature, the opening of the intelligent mixing valve (4) is maintained unchanged.

10. A water dispenser, comprising a control module, characterized in that: The control module is configured to execute the control method of the water dispenser according to any one of claims 1 to 9.

Images