Low-temperature slow cooking control system, control method and slow cooker

Abstract

The invention discloses a low-temperature slow cooking control system and method and a slow cooker. The low-temperature slow cooking control system comprises a heating unit, a power supply unit, a temperature control module and a main control unit, and the heating unit is used for heating water in a container; the power supply unit is used for supplying power to the main control unit and the heating unit; the temperature control module comprises a low-frequency temperature control switch and a high-frequency temperature control switch; in the rapid temperature rising stage, the main control unit controls the low-frequency temperature control switch to be switched on and switched off, and in the accurate temperature control stage, the main control unit controls the high-frequency temperature control switch to be switched on and switched off. In the rapid temperature rise stage, the low-frequency temperature control switch is adopted, the power consumption is low, the service life is long, and the problems that the service life is shortened and temperature control is unstable due to frequent switching on and off are effectively solved. And after entering the accurate temperature control stage, the system can realize accurate control on the water temperature by adopting a high-frequency temperature control switch, quick response and contactless operation, so that the low-temperature slow cooking requirement on temperature-sensitive food materials can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of low-temperature slow cooking temperature control, and more specifically, to a low-temperature slow cooking control system, a control method and a slow cooker. Background Art

[0002] Low temperature slow cooking technology is an emerging molecular cooking method that puts meat, vegetables and other ingredients into a vacuum plastic bag and then cooks them in a container with a low temperature slow cooker. The core is to keep the water temperature constant to ensure that the ingredients are cooked for a long time at an ideal temperature. The optimal cooking time is calculated by determining the temperature range of the protein cells of each ingredient when they are heated and burst. The low temperature slow cooker heats the water at a constant temperature and makes it flow, so that the ingredients in the vacuum bag are cooked at a stable and uniform temperature.

[0003] There are many technical limitations in the low-temperature slow cookers currently on the market. For example, the heating control systems of existing products on the market are single-mode, using either thyristor high-power drive or relay-controlled heating systems; although thyristor drive has the advantages of fast response, contactless operation, no sparks, no noise, high efficiency, and low cost, it will generate high heat when running at high power for a long time, posing a safety hazard, and requires a large heat sink, which is difficult to achieve in equipment with limited space. For this reason, power reduction operation is usually adopted to achieve a balance between heat dissipation and power, but this will slow down the heating speed, especially in open containers, it is difficult to achieve the ideal cooking temperature.

[0004] The relay-controlled heating system has the advantages of low power consumption, direct contact and low heat generation. However, in the process of precise temperature control, the relay needs to be switched frequently, and its life is usually only hundreds of thousands of times, which is prone to switch failure or contact adhesion. In order to extend the life of the relay, a common method is to extend the switching time to find a balance between life and temperature accuracy. However, this method will reduce the accuracy of temperature control, thereby affecting the taste of some temperature-sensitive ingredients.

[0005] The above shortcomings need to be improved. Summary of the invention

[0006] In order to solve or alleviate the problem in the prior art that low-temperature slow cookers are difficult to quickly and accurately control the temperature, the present invention provides a low-temperature slow cooking control system, a control method and a slow cooker.

[0007] The technical solution of the present invention is as follows:

[0008] A low-temperature slow cooking control system comprises: a heating unit, a power supply unit, a temperature control module, and a main control unit, wherein the heating unit is used for heating water in a container; the power supply unit is used for supplying power to the main control unit and the heating unit; the temperature control module is arranged between the main control unit and the heating unit, the temperature control module comprises a low-frequency temperature control switch and a high-frequency temperature control switch, and the low-frequency temperature control switch and the high-frequency temperature control switch are independently connected to the circuit between the main control unit and the heating unit; the main control unit is arranged between the power supply unit and the heating unit, in the rapid heating stage, the main control unit controls the on and off of the low-frequency temperature control switch, and in the precise temperature control stage, the main control unit controls the on and off of the high-frequency temperature control switch.

[0009] In the above-mentioned low-temperature slow cooking control system, a heating protection unit is arranged between the power supply unit and the temperature control module. The heating protection unit is used to control the on-off of the line between the power supply unit and the temperature control module. The heating protection unit includes an active heating protection unit and a passive heating protection unit. The main control unit controls the on-off of the active heating protection unit, and the passive heating protection unit is automatically disconnected.

[0010] The above-mentioned low-temperature slow cooking control system also includes a stirring execution unit. A stirring control unit is arranged between the stirring execution unit and the power supply unit. The main control unit controls the on and off of the stirring control unit.

[0011] The above-mentioned low-temperature slow cooking control system also includes a human-computer interaction unit electrically connected to the main control unit, and the human-computer interaction unit is used to control the main control unit and display the system operation status.

[0012] The above-mentioned low-temperature slow cooking control system also includes a wireless communication module electrically connected to the main control unit. The main control unit exchanges information with the remote terminal through the wireless communication module, and the remote terminal monitors the main control unit through the wireless communication module.

[0013] In the above-mentioned low-temperature slow cooking control system, a temperature detection unit is provided at the high-frequency temperature control switch, and the temperature detection unit is used to monitor the temperature of the high-frequency temperature control switch and transmit the data to the main control unit.

[0014] In the above-mentioned low-temperature slow cooking control system, the heating unit comprises:

[0015] A heating device is provided with an overheat detection module, which monitors the temperature of the heating device and transmits the data to the main control unit;

[0016] A water temperature detection module, which is used to monitor the water temperature in the container and transmit the data to the main control unit;

[0017] The water level detection module is used to monitor the water level in the container and transmit the data to the main control unit.

[0018] A low temperature slow cooking control method, using the above-mentioned low temperature slow cooking control system, comprises the following steps:

[0019] S1. In the rapid heating stage, the main control unit controls the heating unit to heat the water in the container through the low-frequency temperature control switch until the water temperature rises to a first preset temperature;

[0020] S2, in the precise temperature control stage, the main control unit adjusts the temperature of the water in the heating container by the heating unit through the high-frequency temperature control switch, so that the water temperature rises and stabilizes at the second preset temperature;

[0021] The first preset temperature is not greater than the second preset temperature, and the temperature difference is less than 5°C, preferably 1°C.

[0022] Further, in S1 and / or S2, the stirring execution unit is controlled according to the temperature rise rate v, where v is the heating time per heating of the first unit temperature ΔT1.

[0023] Further, in S2, heating is controlled according to the amount of water in the container.

[0024] Calculate the current water volume:

[0025]

[0026] T0=T1

[0027] L0 is the current water volume; t0 is the heating time per second unit temperature ΔT2, T0 is the current temperature, L1 is the unit water volume, t1 is the heating time per second unit temperature ΔT2 of the unit water volume from 5°C to 95°C in a 25°C environment, and T1 is the temperature of the unit water volume;

[0028] Calculate the heat dissipation coefficient based on the current water volume:

[0029]

[0030] Q W =mcΔT

[0031] Q K =P×t0

[0032] Calculate the basic value of the high-frequency temperature control switch control ratio according to the heat dissipation coefficient:

[0033] k=F×100

[0034] Q W is the heat of water, m is the mass of water, m = ρwater × L0, c is the specific heat capacity of water, ΔT is the temperature difference before and after heating, Q K is the heating heat of the heating unit, and P is the heating power of the high-frequency temperature control switch.

[0035] Furthermore, when the first unit temperature ΔT1 = 1°C and the second unit temperature ΔT2 = 5°C, the temperature rise rate is:

[0036] v=t0 / 5

[0037] The stirring execution unit is controlled according to the temperature rise rate v.

[0038] Furthermore, in S2, the high-frequency temperature control switch operates periodically according to the adjustment period t.

[0039] Calculate the control ratio of high-frequency temperature control switch: u(t)=k+e(t)

[0040] e(t) is the adjustment coefficient output at time t, with an initial value of 0.

[0041] When the temperature deviation ΔTd is continuously positive within the adjustment period t, the adjustment coefficient is incremented by 1, i.e., e(t)=e(t+1);

[0042] When the temperature deviation ΔTd is continuously negative within the adjustment period t, the adjustment coefficient is reduced by 1, that is, e(t) = e(t)-1;

[0043] When the temperature deviation ΔTd is continuously 0 within the adjustment period t, the adjustment coefficient e(t) value remains unchanged;

[0044] The adjustment period t is the heating time for each heating of the third unit temperature ΔT3, and ΔTd is the difference between the cooking temperature and the current water temperature.

[0045] Further, when the third unit temperature ΔT3 = 0.1° C., the adjustment period t = v / 10.

[0046] A slow cooker applies the above-mentioned low-temperature slow cooking control system or executes the above-mentioned low-temperature slow cooking control method.

[0047] The beneficial effect of the present invention according to the above scheme is that, in the rapid heating stage, the present invention effectively avoids the problems of shortened life and unstable temperature control caused by frequent switching by adopting a low-frequency temperature control switch with its low power consumption and long life. After entering the precise temperature control stage, by adopting a high-frequency temperature control switch, its fast response and contactless operation characteristics enable the system to achieve precise control of water temperature, which can meet the requirements of low-temperature slow cooking of temperature-sensitive ingredients. In addition, by intelligently switching between low-frequency and high-frequency temperature control switches, the system also optimizes energy efficiency, which not only reduces energy waste but also extends the service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0049] Figure 1 It is a system framework diagram of the present invention;

[0050] Figure 2 This is a circuit diagram of the temperature control module of the present invention;

[0051] Figure 3 It is a step diagram of the method of the present invention;

[0052] Figure 4 It is a logic diagram of the method of the present invention;

[0053] Figure 5 It is a schematic diagram of the three-dimensional structure of the device in the present invention;

[0054] Figure 6 It is a structural explosion diagram of the device in the present invention.

[0055] Among them, the figure marks in the figure are: 1. Heating unit; 101. Heating device; 102. Overheating detection module; 103. Water temperature detection module; 104. Water level detection module; 2. Power supply unit; 3. Temperature control module; 301. Low-frequency temperature control switch; 302. High-frequency temperature control switch; 4. Main control unit; 5. Heating protection unit; 501. Active heating protection unit; 502. Passive heating protection unit; 6. Stirring execution unit; 7. Stirring control unit; 8. Temperature detection unit; 9. Human-computer interaction unit; 10. Wireless communication module; 11. Analog-to-digital conversion module; 12. Linear regulator. DETAILED DESCRIPTION

[0056] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0057] It should be noted that when a component is referred to as being "fixed" or "set" or "connected" to another component, it may be located directly or indirectly on the other component. The directions or positions indicated by the terms "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the directions or positions shown in the accompanying drawings and are only for the convenience of description and should not be construed as limitations on the present technical solution. The terms "first", "second", etc. are only used for the convenience of description and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features. "Multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0058] like Figure 1 As shown, a low-temperature slow cooking control system described in an embodiment of the present invention includes: a heating unit 1, a power supply unit 2, a temperature control module 3, and a main control unit 4, wherein the heating unit 1 is used to heat water in a container; the power supply unit 2 is used to supply power to the main control unit 4 and the heating unit 1; the temperature control module 3 is arranged between the main control unit 4 and the heating unit 1, and the temperature control module 3 includes a low-frequency temperature control switch 301 and a high-frequency temperature control switch 302, and the low-frequency temperature control switch 301 and the high-frequency temperature control switch 302 are independently connected to the circuit between the main control unit 4 and the heating unit 1; the main control unit 4 is arranged between the power supply unit 2 and the heating unit 1, and in the rapid heating stage, the main control unit 4 controls the low-frequency temperature control switch 301 to be turned on and off, and in the precise temperature control stage, the main control unit 4 controls the high-frequency temperature control switch 302 to be turned on and off.

[0059] During the rapid temperature rise stage, the main control unit 4 chooses to control the low-frequency temperature control switch 301 (such as a relay) for on-off operation. Since the contacts of the relay are in direct contact during the switching process, the power consumption and heat generation are low, and the heating device continues to operate at the rated power, so that the temperature rise in this stage is rapid and stable. As the water temperature gradually approaches the preset ideal cooking temperature, such as within 5°C of the ideal cooking temperature, the system enters the precise temperature control stage. At this time, the main control unit 4 switches to control the high-frequency temperature control switch 302 (such as a thyristor) for on-off, which can respond quickly and operate without contact, realize precise adjustment of the water temperature, control the temperature difference within ±0.1°C, and the high-frequency temperature control switch 302 does not need to be in continuous contact, and the temperature rise is small.

[0060] In this embodiment, in the rapid temperature rise stage, by adopting a low-frequency temperature control switch 301 (such as a relay), with its low power consumption and long life, the problems of shortened life and unstable temperature control caused by frequent switching are effectively avoided. After entering the precise temperature control stage, by adopting a high-frequency temperature control switch 302 (such as a thyristor), its fast response and contactless operation characteristics enable the system to achieve precise control of water temperature, which can meet the requirements of low-temperature slow cooking for temperature-sensitive ingredients. In addition, by intelligently switching the low-frequency temperature control switch 301 and the high-frequency temperature control switch 302, the system achieves energy efficiency optimization, which not only reduces energy waste, but also extends the service life of the equipment.

[0061] In this embodiment, the power supply unit 2 is AC power. In practical applications, DC power or AC power can be used. DC power is powered by an external DC power supply or a built-in battery. One path of AC power is converted into analog-to-digital power by an analog-to-digital conversion module 11 (AC-DC), and then stabilized by a linear regulator 12 (LDO) to supply power to the main control unit 4, which is a microcontroller. Another path of AC power is supplied to the heating unit 1 through a temperature control module 3.

[0062] Specifically, Figure 2 As shown, the system heating unit 1 is controlled by the thyristor Q1 and the relay K2 for collaborative heating. The MCU outputs the SCR_CS signal to control the thyristor through the optocoupler U1 with zero-crossing detection. When the thyristor is turned on, the live wire L is connected to the heating device HE through the thyristor for heating. The resistor R5 and the capacitor CX3 form a surge absorption circuit to prevent the surge voltage from damaging the bidirectional thyristor. The transistor Q4 controls the relay K1 switch for heating, and the diode D2 is to protect the relay, prevent voltage peaks and reverse shocks, and reduce electromagnetic interference.

[0063] A heating protection unit 5 is arranged between the power supply unit 2 and the temperature control module 3. The heating protection unit 5 is used to control the on / off of the line between the power supply unit 2 and the temperature control module 3. The heating protection unit 5 includes an active heating protection unit 501 and a passive heating protection unit 502. The main control unit 4 controls the on / off of the active heating protection unit 501, and the passive heating protection unit 502 is automatically disconnected.

[0064] Specifically, the active heating protection unit 501 is an intelligent switch, such as a relay, and the passive heating protection unit 502 is a fuse. The specific types of the active heating protection unit 501 and the passive heating protection unit 502 are selected according to needs and are not limited to the listed types.

[0065] When the subsequent control unit fails, such as the temperature control module 3, the main control unit 4 controls the relay of the active heating protection unit 501 to disconnect, thereby cutting off the power supply of the heating unit 1 to prevent overheating or other potential dangers caused by control failure. Alternatively, when the current of the subsequent circuit is too large, such as overcurrent caused by a failure or short circuit of the heating unit 1, the fuse will automatically blow, quickly cutting off the line connection between the power supply unit 2 and the temperature control module to prevent the fault from further expanding and protect the entire system from damage.

[0066] In this embodiment, by providing the heating protection unit 5, the low-temperature slow cooking control system has been significantly improved in terms of safety. The active heating protection unit 501 enables the system to quickly cut off the power supply when the failure of the subsequent control unit is detected, effectively preventing equipment damage or safety accidents that may be caused by control failure. At the same time, the passive heating protection unit 502 provides an additional safety guarantee for the system, which can automatically cut off the circuit when the current increases abnormally, prevent the fault from further expanding, and protect other components of the system from damage. The active heating protection unit 501 and the passive heating protection unit 502 in the heating protection unit 5 constitute a dual protection mechanism, which improves the stability and reliability of the low-temperature slow cooking control system and ensures the safety of user use.

[0067] Specifically, Figure 2 As shown, fuse F1 and relay K1 are used for post-stage failure protection. When the current flowing through fuse F1 exceeds the limit current, fuse F1 automatically blows; when the heating device overheats, it triggers relay K1 to cut off the AC power; transistor Q3 controls the switch of relay K1, and diode D1 is to protect the relay, prevent voltage peaks and reverse shocks, and reduce electromagnetic interference.

[0068] The function of capacitors CX1 and CX2 is to suppress electromagnetic interference in the power line and ensure the stable operation of the circuit; the function of varistor RV1 is lightning protection and overvoltage protection.

[0069] like Figure 1 As shown, in a preferred embodiment, the low-temperature slow cooking control system further includes a stirring execution unit 6, a stirring control unit 7 is arranged between the stirring execution unit 6 and the power supply unit 2, and the main control unit 4 controls the stirring control unit 7 to be turned on and off. The stirring execution unit 6 includes a motor and a stirring fan blade arranged on the output shaft of the motor. The stirring fan blade is used to stir the water evenly so that the food is heated evenly.

[0070] When the system starts and reaches the preset cooking conditions, the main control unit 4 will send instructions to the stirring control unit 7 according to the current cooking needs and the water temperature changes. After receiving the instructions, the stirring control unit 7 will control the on and off of the motor and the adjustment of the speed. After the motor is powered on, it drives the stirring blades to rotate. The rotation of the blades causes the water in the cooking container to flow, thereby achieving a uniform distribution of the water temperature. At the same time, the stirring control unit 7 can adjust the speed of the motor in real time according to the instructions of the main control unit 4 to meet the requirements of water temperature uniformity in different cooking stages. For example, in the early stage of cooking, when the temperature rises faster, a higher stirring speed is required to quickly improve the uniformity of the water temperature; when the temperature rise is slower, the water temperature is already relatively stable, and the stirring speed can be reduced at this time to reduce energy consumption and avoid excessive disturbance of the food.

[0071] In this embodiment, by controlling the rotation of the stirring blades, the water temperature in the cooking container is made uniform, ensuring that the food can be heated evenly during the cooking process, avoiding the problem of partial overheating or undercooking of the food due to uneven water temperature. Secondly, the stirring control unit 7 can adjust the speed of the motor in real time according to the instructions of the main control unit 4, improve the operational flexibility and intelligence level of the system, and can perform refined control according to cooking needs, further improve the accuracy of the cooking temperature, and ensure the taste of the food.

[0072] Specifically, in a preferred embodiment, the motor is a brushless DC motor, which has the advantages of small size, low noise, low power consumption and less heat. Currently, most low-temperature slow cookers on the market use AC shaded-pole motors, which generate large noise and heat during operation and require additional fans for heat dissipation, making the device structure complex and energy consuming. The slow cooker body is prone to shaking. In addition, the outer shell design must have ventilation holes, which makes it impossible to achieve a waterproof function. During the cooking process, water vapor may enter the body through the fan, which will also cause corrosion and accelerated aging of internal components. In this embodiment, since there is no need for a built-in fan, there is no need for ventilation holes, and a waterproof design is achieved. The device can be safely washed with water, which improves the user experience and the overall reliability of the device.

[0073] like Figure 1 As shown, in a preferred embodiment, the low-temperature slow cooking control system further includes a human-machine interaction unit 9 electrically connected to the main control unit 4, and the human-machine interaction unit 9 is used to control the main control unit 4 and display the system operation status.

[0074] The human-computer interaction unit 9 establishes a bridge between the user and the system, allowing the user to intuitively control the system and obtain system status information. When the user needs to operate through the human-computer interaction unit 9, he will first input instructions through buttons, touch screens or other input devices on the interface. The instructions are then passed to the main control unit 4, which parses and processes the instructions according to preset programs and logic. The main control unit 4 receives and processes the instructions, and adjusts the operating state of the system accordingly, such as adjusting the cooking temperature, starting or stopping the stirring execution unit 6, etc. At the same time, the main control unit 4 will also feed back the current operating state of the system (such as temperature, time, stirring speed, etc.) to the human-computer interaction unit 9, so that the user can view it in real time through a display screen or other display devices. In this way, the user can make further adjustments or monitoring based on the feedback of the system to ensure that the cooking process proceeds as expected.

[0075] In this embodiment, the human-computer interaction unit 9 provides an intuitive and easy-to-use control interface, allowing users to easily perform various settings and operations, improving the usability of the system and improving the user experience. Secondly, by displaying the system operation status in real time, users can understand the cooking progress and various parameters at any time, so as to make timely adjustments to ensure cooking quality and safety. In addition, the human-computer interaction unit 9 makes the system more intelligent, allowing users to make personalized settings according to personal preferences and needs, and improving cooking flexibility.

[0076] like Figure 1 As shown, in a preferred embodiment, the low-temperature slow cooking control system also includes a wireless communication module 10 electrically connected to the main control unit 4. The main control unit 4 exchanges information with the remote terminal through the wireless communication module 10, and the remote terminal monitors the main control unit 4 through the wireless communication module 10.

[0077] The user opens the corresponding APP on a remote terminal such as a smartphone or tablet computer. In the APP, the user can browse and select the desired recipe, which contains detailed parameters such as the target cooking temperature and cooking time. Once the user selects the recipe, the APP will send these parameters to the main control unit 4 of the slow cooker through the wireless communication module 10. After receiving these parameters, the main control unit 4 will adjust the operating state of the slow cooker according to its internal control logic and algorithm to match the cooking conditions set by the user. At the same time, the main control unit 4 will also send the operating status information of the slow cooker, such as the current temperature, remaining cooking time, etc., to the remote terminal in real time through the wireless communication module 10, so that the user can monitor the cooking progress and status at any time. In this way, when the user is away from the slow cooker, he can also remotely control and monitor the slow cooker through the APP.

[0078] In this embodiment, the wireless communication module 10 realizes remote control and monitoring of the slow cooker, allowing the user to operate and monitor the slow cooker through smart devices such as mobile phones without being restricted by location and time, thereby improving the flexibility and convenience of the system. Secondly, through the built-in recipes in the APP, users can easily obtain and apply professional cooking parameters without manual input or memorization, thereby reducing the difficulty of operation.

[0079] like Figure 1 As shown, in a preferred embodiment, a temperature detection unit 8 is provided at the high-frequency temperature-controlled switch 302 , and the temperature detection unit 8 is used to monitor the temperature of the high-frequency temperature-controlled switch 302 and transmit the data to the main control unit 4 .

[0080] The temperature detection unit 8 is a temperature sensor installed on the high-frequency temperature-controlled switch 302 so as to monitor the temperature change of the high-frequency temperature-controlled switch 302 in real time and accurately during operation. When the high-frequency temperature-controlled switch 302 starts to work, the temperature detection unit 8 records the temperature data of the switch and transmits the collected data to the main control unit 4. The main control unit 4 receives and analyzes the temperature data and determines whether the high-frequency temperature-controlled switch 302 is in a normal working state according to the preset safety threshold. If the temperature of the thyristor rises abnormally and exceeds the safety range, the main control unit 4 will respond quickly and take necessary protective measures, such as reducing power output, cutting off power supply, etc., to prevent the switch from being damaged by overheating and ensure the safe operation of the system.

[0081] In this embodiment, the temperature detection unit 8 cooperates with the main control unit 4 to monitor and warn the high-frequency temperature control switch 302 in real time, so that temperature abnormalities can be discovered and handled in time, and safety hazards such as equipment damage and fire caused by overheating can be prevented, thereby ensuring the safety of personnel and property and improving the safety and reliability of the system.

[0082] like Figure 1 As shown, in a preferred embodiment, the heating unit 1 comprises:

[0083] A heating device 101 is provided with an overheat detection module 102, which monitors the temperature of the heating device 101 and transmits the data to the main control unit 4;

[0084] A water temperature detection module 103, which is used to monitor the water temperature in the container and transmit the data to the main control unit 4;

[0085] The water level detection module 104 is used to monitor the water level in the container and transmit the data to the main control unit 4 .

[0086] When working, the heating device 101 is responsible for providing the heat required for cooking, and the overheat detection module 102 arranged thereon will continuously monitor the temperature of the heating device 101. When the temperature is detected to be abnormally increased, that is, exceeding the preset safety threshold, the overheat detection module 102 will immediately transmit the abnormal information to the main control unit 4. After receiving the signal, the main control unit 4 will quickly start the corresponding overheat protection mechanism, such as reducing the heating power or completely cutting off the power supply, to prevent the heating device 101 from being damaged by overheating or causing safety hazards such as fire. At the same time, the water temperature detection module 103 is also monitoring the changes in the water temperature in the container in real time, and feeding back the data to the main control unit 4. The main control unit 4 can accurately control the heating power of the heating device 101 based on the water temperature data to keep the water temperature within a suitable cooking range. In addition, the water level detection module 104 is responsible for monitoring the water level in the container. When the water level drops to the preset minimum water level, the alarm mechanism will be triggered, and the cooking process will be automatically shut down through the main control unit 4 to prevent the heating device 101 from burning dry or the food from burning due to the low water level.

[0087] like Figure 3 As shown, a low-temperature slow cooking control method described in one embodiment of the present invention uses the above-mentioned low-temperature slow cooking control system and includes the following steps:

[0088] S1. In the rapid heating stage, the main control unit 4 controls the heating unit 1 to heat the water in the container through the low-frequency temperature control switch 301 until the water temperature rises to a first preset temperature;

[0089] S2, in the precise temperature control stage, the main control unit 4 adjusts the temperature of the water in the heating container by the heating unit 1 through the high-frequency temperature control switch 302, so that the water temperature rises and stabilizes at the second preset temperature;

[0090] The first preset temperature is not greater than the second preset temperature, and the temperature difference is less than 5°C, preferably 1°C. The second preset temperature is the ideal cooking temperature for the food, and the first preset temperature is close to the second preset temperature. This is because in the rapid heating stage, the heating speed is faster, and after entering the precise temperature control stage, a short period of rapid heating will still be maintained. To prevent overheating, the temperature difference is set to buffer the heating speed, facilitate precise temperature control in the precise temperature control stage, and ensure the cooking effect.

[0091] The low-temperature slow cooking control method realizes efficient temperature control during the cooking process by combining the working characteristics of the low-frequency temperature control switch 301 and the high-frequency temperature control switch 302. In the rapid heating stage, the low-frequency temperature control switch 301 is closed due to its low power consumption, direct contact and low heat generation, and the heating device 101 continues to operate at full power, so that the water in the container can be quickly heated to the first preset temperature, the heating time is short, and the cooking efficiency is high. After entering the precise temperature control stage, the high-frequency temperature control switch 302 controls the on-off time ratio of the high-frequency temperature control switch 302 within the adjustment cycle by virtue of its fast response, contactless operation, no sparks, no noise, and high efficiency, and finely controls the heating power of the heating unit 1 to ensure that the water temperature is stably maintained at the second preset temperature, thereby realizing precise control of the cooking temperature. Through the phased and differentiated temperature control strategy, not only the cooking quality of low-temperature slow cooking is improved, but also the safety and stability of the cooking process are ensured, providing users with a high-quality cooking experience.

[0092] like Figure 4 As shown, in a preferred embodiment, in S2, heating is controlled according to the amount of water in the container.

[0093] Calculate the current water volume:

[0094]

[0095] T0=T1

[0096] L0 is the current water volume; t0 is the heating time for each 5°C rise in temperature, T0 is the current temperature, L1 is the unit water volume, t1 is the heating time for each 5°C rise in temperature from 5°C to 95°C in a 25°C environment, and T1 is the unit water volume temperature;

[0097] Calculate the heat dissipation coefficient based on the current water volume:

[0098]

[0099] Q W =mcΔT

[0100] Q K =P×t0

[0101] Calculate the basic value of the control ratio of the high-frequency temperature control switch 302 according to the heat dissipation coefficient:

[0102] k=F×100

[0103] Q W is the heat of water, m is the mass of water, m = ρwater × L0, c is the specific heat capacity of water, ΔT is the temperature difference before and after heating, Q K is the heating heat of the heating unit, and P is the heating power when controlled by the high-frequency temperature control switch.

[0104] In this embodiment, in the precise temperature control stage, the heating process is intelligently controlled according to the actual water volume (L0) and heat dissipation in the container to improve heating efficiency and save energy. First, the system estimates the current water volume L0, and based on the calculated heat dissipation coefficient, the system intelligently adjusts the control ratio of the high-frequency temperature control switch 302 according to the heat dissipation coefficient to reduce the influence of heat dissipation. The faster the heat dissipation, the greater the heating power, and the slower the heat dissipation, the smaller the heating power, so as to ensure the stable and rapid rise of water temperature and avoid energy waste caused by excessive heating.

[0105] like Figure 4 As shown, in a preferred embodiment, in S1 and / or S2, the temperature rise rate is calculated:

[0106] v=t0 / 5

[0107] The stirring execution unit 6 is controlled according to the temperature rise rate v.

[0108] In this embodiment, the stirring execution unit 6 is controlled according to the temperature rise rate v during the rapid heating stage. Specifically, the system first calculates the temperature rise rate v, which reflects the heating efficiency and the speed of the water temperature rise. Based on the calculation results, the working state of the stirring execution unit 6 is intelligently adjusted. When the temperature rise rate is fast, the stirring execution unit 6 will promote the uniform distribution of heat by stirring the water in the container, so that the water temperature rises evenly; when the temperature rise rate is slow, the stirring execution unit 6 will appropriately reduce the stirring frequency or stop working to avoid heat loss caused by excessive stirring. The stirring execution strategy is dynamically adjusted according to the temperature rise rate to improve the uniformity and efficiency of the heating process and ensure the stable rise of the water temperature.

[0109] like Figure 4 As shown, in a preferred embodiment, in S2, the high-frequency temperature control switch 302 operates periodically according to the adjustment period t.

[0110] Calculate the adjustment period: t = v / 10

[0111] Calculate the control ratio of the high-frequency temperature control switch 302: u(t)=k+e(t)

[0112] e(t) is the adjustment coefficient output at time t, with an initial value of 0.

[0113] When the temperature deviation ΔTd is continuously positive within the adjustment period t, the adjustment coefficient is incremented by 1, i.e., e(t)=e(t+1);

[0114] When the temperature deviation ΔTd is continuously negative within the adjustment period t, the adjustment coefficient is reduced by 1, that is, e(t) = e(t)-1;

[0115] When the temperature deviation ΔTd is continuously 0 within the adjustment period t, the adjustment coefficient e(t) value remains unchanged;

[0116] ΔTd is the difference between the cooking temperature and the current water temperature.

[0117] The adjustment cycle t is dynamically set to v / 10 according to the temperature rise rate v, and the adjustment accuracy can reach 0.1°C; the control ratio u(t) of the high-frequency temperature control switch 302 is automatically controlled according to the temperature deviation ΔTd through the combination of the basic value k and the dynamic adjustment coefficient e(t). When ΔTd is continuously positive or negative, e(t) increases or decreases accordingly, effectively responding to temperature fluctuations and ensuring the precise maintenance of cooking temperature; when ΔTd is zero, e(t) remains unchanged, avoiding unnecessary adjustments, maintaining the stability of the system, improving the intelligence level of the temperature control system, improving the stability of the temperature during the cooking process, and ensuring the cooking effect.

[0118] like Figure 5 and Figure 6 As shown, a slow cooker described in one embodiment of the present invention applies the above-mentioned low-temperature slow cooking control system or executes the above-mentioned low-temperature slow cooking control method.

[0119] In this embodiment, by applying the above-mentioned low-temperature slow cooking control system or low-temperature slow cooking control method, the heating power and stirring frequency can be intelligently adjusted according to the amount of water in the container and the temperature rise rate, ensuring that the water temperature quickly and stably reaches the first preset temperature in the rapid temperature rise stage, and in the precise temperature control stage, by periodically adjusting the high-frequency temperature control switch 302, it is possible to achieve fine control of the cooking temperature and reduce temperature fluctuations. Intelligent temperature management strategies can improve the taste of cooked food, extend the service life of the slow cooker, and reduce energy consumption. In addition, the slow cooker has friendly human-computer interaction, and users can easily set and adjust cooking parameters according to different ingredients and cooking needs, and enjoy a more personalized and convenient cooking experience.

[0120] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A low temperature slow cooking control system, characterized in that: include: A heating unit, the heating unit is used to heat the water in the container; A power supply unit, the power supply unit is used to supply power to the main control unit and the heating unit; A temperature control module is provided between the main control unit and the heating unit. The temperature control module includes a low-frequency temperature control switch and a high-frequency temperature control switch. The low-frequency temperature control switch and the high-frequency temperature control switch are independently connected to the circuit between the main control unit and the heating unit. The main control unit is arranged between the power supply unit and the heating unit. In the rapid temperature rise stage, the main control unit controls the on and off of the low-frequency temperature control switch. In the precise temperature control stage, the main control unit controls the on and off of the high-frequency temperature control switch.

2. A low temperature slow cooking control system according to claim 1, characterized in that: A heating protection unit is arranged between the power supply unit and the temperature control module. The heating protection unit is used to control the on-off of the line between the power supply unit and the temperature control module. The heating protection unit includes an active heating protection unit and a passive heating protection unit. The main control unit controls the on-off of the active heating protection unit, and the passive heating protection unit is automatically disconnected.

3. A low temperature slow cooking control system according to claim 1, characterized in that: It also includes a stirring execution unit. A stirring control unit is arranged between the stirring execution unit and the power supply unit. The main control unit controls the stirring control unit to be turned on and off.

4. A low temperature slow cooking control system according to claim 1, characterized in that: A temperature detection unit is provided at the high-frequency temperature control switch, and the temperature detection unit is used to monitor the temperature of the high-frequency temperature control switch and transmit the data to the main control unit.

5. A low temperature slow cooking control system according to claim 1, characterized in that: The heating unit includes: A heating device is provided with an overheat detection module, which monitors the temperature of the heating device and transmits the data to the main control unit; A water temperature detection module, which is used to monitor the water temperature in the container and transmit the data to the main control unit; The water level detection module is used to monitor the water level in the container and transmit the data to the main control unit.

6. A low temperature slow cooking control method, characterized in that: The application of the low temperature slow cooking control system described in claim 1 comprises the following steps: S1. In the rapid heating stage, the main control unit controls the heating unit to heat the water in the container through the low-frequency temperature control switch until the water temperature rises to a first preset temperature; S2. In the precise temperature control stage, the main control unit adjusts the temperature of the water in the heating container by the heating unit through the high-frequency temperature control switch, so that the water temperature rises and stabilizes at the second preset temperature.

7. A low temperature slow cooking control method according to claim 6, characterized in that: In S1 and / or S2, the stirring execution unit is controlled according to the temperature rise rate v, where v is the heating time per temperature rise of the first unit temperature ΔT1.

8. A low temperature slow cooking control method according to claim 6, characterized in that: In S2, heating is controlled according to the amount of water in the container. Calculate the current water volume: T0=T1 L0 is the current water volume; t0 is the heating time per second unit temperature ΔT2, T0 is the current temperature, L1 is the unit water volume, t1 is the heating time per second unit temperature ΔT2 of the unit water volume from 5°C to 95°C in a 25°C environment, and T1 is the temperature of the unit water volume; Calculate the heat dissipation coefficient based on the current water volume: Q W =mcΔT Q K =P×t0 Calculate the basic value of the high-frequency temperature control switch control ratio according to the heat dissipation coefficient: k=F×100 Q W is the heat of water, m is the mass of water, m = ρ 水 ×L0, c is the specific heat capacity of water, ΔT is the temperature difference before and after heating, Q K is the heating heat of the heating unit, and P is the heating power of the high-frequency temperature control switch.

9. A low temperature slow cooking control method according to claim 8, characterized in that: In S2, the high-frequency temperature control switch operates periodically according to the adjustment period t. Calculate the control ratio of high-frequency temperature control switch: u(t)=k+e(t) e(t) is the adjustment coefficient output at time t, with an initial value of 0. When the temperature deviation ΔT d If it is a positive number continuously within the adjustment period t, the adjustment coefficient is incremented by 1, i.e., e(t)=e(t+1); When the temperature deviation ΔT d If it is a negative number continuously within the adjustment period t, the adjustment coefficient is reduced by 1, that is, e(t) = e(t)-1; When the temperature deviation ΔT d When it is continuously 0 in the adjustment period t, the adjustment coefficient e(t) value remains unchanged; The adjustment period t is the heating time per heating of the third unit temperature ΔT3, ΔT d The difference between the cooking temperature and the current water temperature.

10. A slow cooker, characterized in that: Apply the low-temperature slow cooking control system described in claim 1 or execute the low-temperature slow cooking control method described in claim 6.

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