Power control circuit and method and wireless heating device

Abstract

The invention discloses a power control circuit and method and a wireless heating device, the power control circuit comprises a direction detection module, a voltage detection module and a control module, and the control module is connected to the direction detection module and the voltage detection module. The voltage amplitude determination module is used for determining the voltage amplitude of the first capacitor according to a direction signal corresponding to the direction of the current flowing through the first resistor and input by the direction detection module and a voltage signal corresponding to the capacitor voltage of the first capacitor and input by the voltage detection module; and controlling the heating power of the wireless heating device according to a comparison result of the voltage amplitude and a target amplitude corresponding to the current heating power of the wireless heating device. Through the comparison result of the real-time voltage amplitude and the target amplitude, the change of the material of the cookware in the heating process can be judged, and then the heating power of the wireless heating device is adjusted in real time, so that the effect of protecting the wireless heating device is achieved.

Description

Technical Field

[0001] The present application relates to the technical field of wireless heating, and more specifically, to a power control circuit, method and wireless heating device. Background Art

[0002] Wireless heating devices are increasingly used in people's daily lives due to their convenience and practicality. Usually, a wireless heating device can be adapted to a variety of different types of pots, so that people can make and process various types of food. However, for different types of pots, when the wireless heating device emits the same power, the power that can be absorbed is different. Even for the same pot, the power that can be absorbed before and after may change due to the movement of the user during the heating process, which in turn causes a significant change in the magnitude of the current flowing through the wireless heating device, affecting the circuit safety in the wireless heating device. Summary of the invention

[0003] In view of the above problems, the present application proposes a power control circuit, method and wireless heating device to improve the above problems.

[0004] In the first aspect, the embodiment of the present application provides a power control circuit, which is applied to a wireless heating device, wherein the wireless heating device is used to heat the carried pot, and the wireless heating device includes a heating coil, a first resistor and a first capacitor, wherein the heating coil, the first resistor and the first capacitor are connected in series in sequence, and include: a direction detection module, a voltage detection module and a control module. Among them, the direction detection module is connected to both ends of the first resistor, and is used to detect the direction of the current flowing through the first resistor; the voltage detection module is connected to one end of the first capacitor, and is used to detect the capacitor voltage of the first capacitor; the control module is connected to the direction detection module and the voltage detection module, and is used to determine the voltage amplitude of the first capacitor according to the direction signal corresponding to the current direction input by the direction detection module and the voltage signal corresponding to the capacitor voltage input by the voltage detection module, and control the heating power of the wireless heating device according to the comparison result of the voltage amplitude and the target amplitude corresponding to the current heating power of the wireless heating device.

[0005] In a second aspect, an embodiment of the present application provides a power control method, which is applied to a wireless heating device, wherein the wireless heating device is used to heat a carried cookware, the wireless heating device comprising a heating coil and a first resistor and a first capacitor connected in series to the heating coil, and the cookware detection method comprising: obtaining a direction signal and a voltage signal, the direction signal being used to characterize the direction of a current flowing through the first resistor, and the voltage signal being used to characterize the capacitor voltage of the first capacitor; determining a voltage amplitude of the first capacitor based on the direction signal and the voltage signal; and controlling the heating power of the wireless heating device based on a comparison result of the voltage amplitude with a target amplitude corresponding to the current heating power of the wireless heating device.

[0006] In a third aspect, an embodiment of the present application provides a wireless heating device, which includes a heating coil, a first resistor, a first capacitor and the power control circuit provided in the first aspect above, and the heating coil, the first resistor and the first capacitor are connected in series in sequence.

[0007] The power control circuit provided by the present invention is applied to a wireless heating device, which is used to heat the pot carried by the wireless heating device, and the wireless heating device includes a heating coil, a first resistor and a first capacitor, and the heating coil, the first resistor and the first capacitor are connected in series in sequence. The power control circuit includes a direction detection module, a voltage detection module and a control module, wherein the direction detection module is connected to both ends of the first resistor to detect the direction of the current flowing through the first resistor; the voltage detection module is connected to one end of the first capacitor to detect the capacitor voltage of the first capacitor; the control module is connected to the direction detection module and the voltage detection module, and is used to determine the voltage amplitude of the first capacitor according to the direction signal corresponding to the current direction input by the direction detection module and the voltage signal corresponding to the capacitor voltage input by the voltage detection module, and control the heating power of the wireless heating device according to the comparison result of the voltage amplitude and the target amplitude corresponding to the current heating power of the wireless heating device. Therefore, by comparing the real-time voltage amplitude with the target amplitude corresponding to the current heating power, the change of the material of the pot during the heating process can be judged, and then the heating power of the wireless heating device can be adjusted in real time to ensure that the current in the wireless heating device is always within a safe range, so as to achieve the effect of protecting the wireless heating device. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0009] Figure 1 A schematic diagram of the structure of a power control circuit provided in an embodiment of the present application is shown.

[0010] Figure 2 A specific structural schematic diagram of the direction detection module provided in an embodiment of the present application is shown.

[0011] Figure 3 A specific structural schematic diagram of the voltage detection module provided in an embodiment of the present application is shown.

[0012] Figure 4 A schematic flow chart of a power control method provided in an embodiment of the present application is shown.

[0013] Figure 5 A specific flow chart of step S120 in the power control method provided in an embodiment of the present application is shown.

[0014] Figure 6 A specific flow chart of step S130 in the power control method provided in an embodiment of the present application is shown.

[0015] Figure 7 A schematic structural diagram of a wireless heating device provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0016] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0017] In the field of wireless heating technology, the coil in the wireless heating device is usually used to heat the pot. By loading alternating current of a certain frequency at both ends of the coil, an alternating magnetic field will be generated. If the pot is placed in the alternating magnetic field, an induced current will be generated inside, which can heat the object inside the pot. Due to the different coupling degrees between the pot and the coil and the different parameters such as the pot's own resistance, or the relative position between the pot and the coil may move during the heating process, which may cause the pot material to change, the power that the pot can absorb under the same heating power is also different, and the current flowing through the wireless heating device is also different. In order to ensure the safety of the circuit in the wireless heating device, different heating powers need to be output for different pot materials.

[0018] In the related art, in order to detect the material of the pot carried by the wireless heating device, usually, the coil can only be powered for a fixed period of time before the pot is heated, and then the power supply to the coil is stopped. By detecting the number of reversals of the current in the coil, it is determined whether the coil carries the pot and the material of the pot. It can be understood that the pots carried by the wireless heating device are of different materials, and the power they can absorb is different, and the power left in the coil is also different, which can be expressed as different coil current reversals. If the pot material is good and absorbs more power, the number of coil current reversals will decrease, and the number of current reversals will increase significantly. However, this detection method is easily interfered by the external magnetic field. The coil disk will absorb the energy of the interference, affecting the number of current reversals, and then affecting the determination of the pot material. And this material determination method cannot be performed during the heating of the pot, that is, it cannot cope with the situation where the pot material changes due to the movement of the pot.

[0019] In order to improve the above problems, the inventors proposed the power control circuit, method and wireless heating device provided by the present application. The power control circuit includes a direction detection module, a voltage detection module and a control module. The control module is connected to the direction detection module and the voltage detection module, and is used to determine the voltage amplitude of the first capacitor according to the direction signal corresponding to the direction of the current flowing through the first resistor input by the direction detection module, and the voltage signal corresponding to the capacitor voltage of the first capacitor input by the voltage detection module, and control the heating power of the wireless heating device according to the comparison result of the voltage amplitude and the target amplitude corresponding to the current heating power of the wireless heating device. By comparing the real-time voltage amplitude with the target amplitude corresponding to the current heating power, it is possible to judge the change of the material of the pot during the heating process, and then adjust the heating power of the wireless heating device in real time to ensure that the current in the wireless heating device is always within a safe range, so as to achieve the effect of protecting the wireless heating device.

[0020] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0021] like Figure 1As shown, it shows a schematic diagram of the structure of a power control circuit 100 provided in an embodiment of the present application. The power control circuit 100 is applied to a wireless heating device 200, and the wireless heating device 200 is used to heat the carried pot. The wireless heating device 200 includes a heating coil, a first resistor R1 and a first capacitor C1, and the heating coil, the first resistor R1 and the first capacitor C1 are connected in series in sequence. The power control circuit 100 includes a direction detection module 120, which is connected to both ends of the first resistor R1 and is used to detect the direction of the current flowing through the first resistor R1; a voltage detection module 130, which is connected to one end of the first capacitor C1 and is used to detect the capacitor voltage of the first capacitor C1; a control module 110, which is connected to the direction detection module 120 and the voltage detection module 130, and is used to determine the voltage amplitude of the first capacitor C1 according to the direction signal corresponding to the current direction input by the direction detection module 120 and the voltage signal corresponding to the capacitor voltage input by the voltage detection module 130, and control the heating power of the wireless heating device 200 according to the comparison result of the voltage amplitude with the target amplitude corresponding to the current heating power of the wireless heating device 200.

[0022] In the embodiment of the present application, during the process of the wireless heating device 200 heating the pot, the control module 110 in the power control circuit 100 can obtain the direction signal corresponding to the direction of the current flowing through the first resistor R1 through the direction detection module 120, and obtain the voltage signal corresponding to the capacitor voltage flowing through the first capacitor C1 through the voltage detection module 130, and determine the voltage amplitude of the first capacitor C1 based on the direction signal and the voltage signal, and then judge the pot material by the voltage amplitude, and determine the heating power of the wireless heating device 200. It can be understood that since the inductance and resistance of different pot materials coupled with the coil are different, when the same power is generated in the wireless heating device 200, the better the material of the pot, the more power it absorbs, the less residual power remains in the coil, and the smaller the voltage amplitude of the first capacitor C1 connected in series with the coil. On the contrary, when the same power is generated in the wireless heating device 200, if the material of the pot deteriorates, the voltage amplitude of the first capacitor C1 will also increase accordingly, that is, the current flowing through the circuit of the wireless heating device 200 increases. If the current is too large at this time, it may affect the components such as the insulated gate bipolar transistor (IGBT) in the circuit, and even break down and damage the components. Therefore, the control module 110 of the power control circuit 100 can detect the voltage amplitude corresponding to the first capacitor C1 in the wireless heating device 200 in real time based on the corresponding relationship between the voltage amplitude and the material of the pot, indirectly judge the current size in the circuit, and then adjust the heating power in real time to protect the circuit.

[0023] It can be understood that, through the above-mentioned power control circuit 100, the basis data for determining the heating power can be converted from the number of current reversals to the voltage amplitude of the first capacitor C1, which can effectively avoid the interference of the external magnetic field on the number of current reversals; and the voltage amplitude of the first capacitor C1 can be obtained in the process of the coil heating the cookware, that is, the control of the heating power can also be expanded from pre-heating detection to real-time detection during the heating process, which can effectively deal with the situation where the material of the cookware changes due to the movement of the cookware during the heating process, and the control of the heating power of the wireless heating device 200 is more accurate, which can further ensure the safety of the circuit in the wireless heating device 200.

[0024] Specifically, the control module 110 in the power control circuit 100 is used to reduce the heating power of the wireless heating device 200 when the voltage amplitude is greater than the target amplitude, and to keep the current heating power of the wireless heating device 200 unchanged when the voltage amplitude is less than or equal to the target amplitude.

[0025] That is to say, if the voltage amplitude corresponding to the first capacitor C1 is greater than the target amplitude, the control module 110 can determine that the current in the wireless heating device 200 exceeds the safety limit at this time, so by reducing the heating power of the wireless heating device 200, the current in the circuit of the wireless heating device 200 is reduced under the same pot material, so as to achieve the effect of protecting the circuit. Similarly, if the voltage amplitude corresponding to the first capacitor C1 is not greater than the target amplitude, that is, under the current heating power, the current in the wireless heating device 200 is within the safety limit range, therefore, the control module 110 can keep the current heating power unchanged to heat the pot to the maximum extent. Among them, the control module 110 determines whether the current in the wireless heating device 200 exceeds the safety limit by the target amplitude, and the target amplitude can be the voltage amplitude corresponding to the first capacitor C1 in the circuit when the wireless heating device 200 carries the pot with the best material under the current heating power. Among them, the pot with the best material can be the original pot of the wireless heating device 200, or the pot with the best power absorption efficiency. If the voltage amplitude of the first capacitor C1 is greater than the target amplitude under the same current power condition, it indicates that the material of the cookware has deteriorated, and the heating power of the wireless heating device 200 can be reduced accordingly.

[0026] In some embodiments, the control module 110 may pre-divide the range of heating power that the wireless heating device 200 can generate into a limited number of grades, and in each grade, the maximum heating power in the grade is used as the heating power corresponding to the grade. The control module 110 may determine the current heating grade based on the current heating power, and when the voltage amplitude of the first voltage is greater than the target amplitude, the current heating grade is reduced by one level to achieve the effect of reducing the heating power. Thereafter, the control module 110 may still obtain the voltage amplitude corresponding to the first capacitor C1 after the heating power is reduced. If the voltage amplitude after the reduction is still greater than the target amplitude, the control module 110 may reduce the current heating grade again.

[0027] In some embodiments, the direction signal includes a first direction signal and a second direction signal, and the control module 110 is used to use the voltage signal at the current moment as the first peak signal when the received direction signal is converted from the second direction signal to the first direction signal, and to use the voltage signal at the current moment as the second peak signal when the received direction signal is converted from the first direction signal to the second direction signal; the control module 110 is also used to determine the voltage amplitude of the first capacitor C1 based on the first peak signal and the second peak signal.

[0028] It can be understood that the voltage across the first capacitor C1 changes in alternating current, and the voltage amplitude corresponding to the first capacitor C1 should be the difference between the maximum positive phase voltage across the first capacitor C1 and the maximum negative phase voltage. Therefore, the control module 110 can accurately determine the occurrence time of the maximum positive phase voltage and the maximum negative phase voltage through the direction signal obtained by the direction detection module 120. That is, when the direction signal received by the control module 110 is converted from the first direction signal to the second direction signal, the voltage signal across the first capacitor C1 is exactly the peak signal, and the voltage signal at this time can be used as the first peak signal corresponding to the first capacitor C1; similarly, when the direction signal is converted from the second direction signal to the first direction signal, the voltage signal across the first capacitor C1 is also exactly the peak signal, and the voltage signal at this time can be used as the second peak signal corresponding to the first capacitor C1. Therefore, the control module 110 can determine the voltage amplitude of the first capacitor C1 based on two different peak signals.

[0029] Specifically, the control module 110 may determine the absolute value of the difference between the first peak signal and the second peak signal, and use the absolute value as the voltage amplitude.

[0030] Obviously, since the first resistor R1 is connected in series with the first capacitor C1, when the direction signal corresponding to the current direction on the first resistor R1 changes, the voltage across the first capacitor C1 happens to be at a peak value. Therefore, the first peak signal and the second peak signal can both represent the peak value of the voltage signal across the first capacitor C1; and, if the direction converted by the direction signal is different, then the direction of the voltage signal across the first capacitor C1 is also different. Therefore, the first peak signal and the second peak signal determined based on different situations of the direction signal conversion are also different. Then the control module 110 can use the absolute value of the difference between the first peak signal and the second peak signal as the voltage amplitude corresponding to the first capacitor C1.

[0031] In the embodiments of the present application, Figure 2 As shown, the direction detection module 120 includes a first detection port, a second detection port and a first output port, the first detection port is connected to the first end of the first resistor R1, the second detection port is connected to the second end of the first resistor R1, and the first output port is connected to the first input port of the control module 110; the direction detection module 120 is used to obtain a first voltage at the first end of the first resistor R1 through the first detection port, and to obtain a second voltage at the second end of the first resistor R1 through the second detection port; the direction detection module 120 is also used to output different direction signals to the first input port through the first output port according to the comparison result of the first voltage and the second voltage, and the direction signal is used to characterize the direction of the current flowing through the first resistor R1.

[0032] It can be understood that the direction signal obtained by the control module 110 is used to characterize the direction of the current flowing through the first resistor R1, and it is obvious that the direction of the current flowing through the first resistor R1 includes two directions. Therefore, the direction signal obtained by the control module 110 also includes a first direction signal and a second direction signal, which are respectively used to characterize different directions of the current flowing through the first resistor R1. Among them, the direction detection module 120 can obtain the voltage of the first end of the first resistor R1 through the first detection port, obtain the voltage of the second end of the first resistor R1 through the second detection port, and determine the direction of the current flowing through the first resistor R1 at different times through the relationship between the voltages at the two ends of the first resistor R1.

[0033] In some embodiments, the direction detection module 120 may include a second resistor R2 and a third resistor R3, one end of the third resistor R3 is grounded, the other end of the third resistor R3 is connected to one end of the second resistor R2, and a first detection port of the direction detection module 120, the other end of the second resistor R2 is connected to the first end of the first resistor R1. The direction detection module 120 may obtain the voltage of the first end of the first resistor R1 after voltage division as the first voltage through the second resistor R2 and the third resistor R3. Similarly, the direction detection module 120 may also include a fourth resistor R4 and a fifth resistor R5, one end of the fifth resistor R5 is grounded, the other end of the fifth resistor R5 is connected to one end of the fourth resistor R4, and a second detection port of the direction detection module 120, the other end of the fourth resistor R4 is connected to the second end of the first resistor R1. The direction detection module 120 may obtain the voltage of the second end of the first resistor R1 after voltage division as the second voltage through the fourth resistor R4 and the fifth resistor R5.

[0034] In some embodiments, the direction detection module 120 may further include a first comparator, the positive input terminal of the first comparator serves as a first detection port, the negative input terminal of the first comparator serves as a second detection port, and the output terminal of the first comparator serves as a first output port of the direction detection module 120. When the first voltage obtained at the positive input terminal is greater than the second voltage obtained at the negative input terminal, the first comparator may output a first level signal to the first input port of the control module 110 through the output terminal, and the first level signal may serve as a first direction signal; and when the first voltage obtained at the positive input terminal is less than or equal to the second voltage obtained at the negative input terminal, the first comparator may output a second level signal to the first input port of the control module 110 through the output terminal, and the second level signal may serve as a second direction signal. Thus, the direction detection module 120 may obtain the direction of the current flowing through the first resistor R1 in real time, and output it to the control module 110 in the form of a first direction signal and a second direction signal.

[0035] In the embodiments of the present application, Figure 3 As shown, the voltage detection module 130 includes a third detection port and a second output port, the third detection port is connected to one end of the first capacitor C1, and the second output port is connected to the second input port of the control module 110; the voltage detection module 130 is used to obtain the capacitor voltage of the first capacitor C1 through the third detection port, and transmit the voltage signal corresponding to the capacitor voltage to the second input port through the second output port.

[0036] It is understandable that the voltage signal acquired by the control module 110 should be a digital signal. The voltage detection module 130 is connected between the control module 110 and the first capacitor C1, and the analog voltage signal at both ends of the first capacitor C1 needs to be converted into a digital voltage signal that can be recognized by the control module 110. Specifically, the voltage detection module 130 may include an adder, an input port of the positive input end of the adder can be connected to one end of the first capacitor C1 as a third detection port, and another input port of the positive input end of the adder can be connected to an external power supply. It is understandable that the control module 110 cannot recognize negative voltages, and the voltage at one end of the first capacitor C1 changes in the form of a sine wave between the maximum voltage value and the minimum voltage value, wherein the minimum voltage value is negative, for example, the voltage at one end of the first capacitor C1 can fluctuate in the form of a sine wave between -1.5V and +1.5V. At this time, the adder can pull the voltage of the positive input terminal of the adder to a positive voltage through an external power supply connected to another input port, that is, pull the voltage fluctuating between -1.5V and +1.5V to a voltage between 0V and +3V, so as to facilitate the recognition of the control module 110. Thereafter, the adder can amplify the voltage of the positive input terminal based on the preset gain value, and the voltage detection module 130 will further convert the amplified voltage into a voltage signal through an analog-to-digital converter, and transmit it to the second input port of the control module 110.

[0037] A power control circuit 100 provided in an embodiment of the present application includes a direction detection module 120, a voltage detection module 130 and a control module 110, wherein the control module 110 is connected to the direction detection module 120 and the voltage detection module 130, and is used to determine the voltage amplitude of the first capacitor C1 according to the direction signal corresponding to the direction of the current flowing through the first resistor R1 input by the direction detection module 120, and the voltage signal corresponding to the capacitor voltage of the first capacitor C1 input by the voltage detection module 130, and control the heating power of the wireless heating device 200 according to the comparison result of the voltage amplitude with the target amplitude corresponding to the current heating power of the wireless heating device 200. Through the comparison result of the real-time voltage amplitude and the target amplitude, the change of the material of the pot during the heating process can be judged, and then the heating power of the wireless heating device 200 can be adjusted in real time to ensure that the current in the wireless heating device 200 is always within a safe range, so as to achieve the effect of protecting the wireless heating device 200.

[0038] See also Figure 4 , Figure 4 A schematic flow chart of a power control method provided by an embodiment of the present application is shown, the method is applied to a wireless heating device, the wireless heating device is used to heat a carried pot, the wireless heating device comprises a heating coil and a first resistor and a first capacitor connected in series to the heating coil. Figure 4 The process shown in the figure is used to explain the power control in detail. The cookware detection method may specifically include the following steps:

[0039] Step S110: obtaining a direction signal and a voltage signal, wherein the direction signal is used to characterize the direction of the current flowing through the first resistor, and the voltage signal is used to characterize the capacitor voltage of the first capacitor.

[0040] In an embodiment of the present application, the control module in the wireless heating device can obtain a direction signal for characterizing the direction of the current in the wireless heating device through the direction detection module, and can also obtain a voltage signal for characterizing the capacitor voltage at one end of the first capacitor through the voltage detection module, so as to determine the voltage amplitude of the first capacitor based on the direction signal and the voltage signal. When the direction of the current flowing through the first resistor changes, the capacitor voltage of the first capacitor just reaches a peak value. Therefore, the control module needs to determine the moment when the current direction in the circuit changes through the direction signal for characterizing the current direction, and then determine the moment when the capacitor voltage reaches a peak value, so as to determine the voltage amplitude of the first capacitor through the peak value of the capacitor voltage.

[0041] Step S120: determining a voltage amplitude of the first capacitor based on the direction signal and the voltage signal.

[0042] In an embodiment of the present application, the control module can obtain the moment when the current direction in the circuit of the wireless heating device changes each time based on the direction signal, and then the capacitor voltage at one end of the first capacitor obtained at the moment when each current direction changes can be used as one of the peak voltages of the first capacitor. It can be understood that the current direction in the circuit includes two types: positive and negative phases, so the control module can characterize different current directions respectively through two different direction signals. The change in the direction signal received by the control module means that the current direction in the circuit has changed. And, since the capacitor voltage at one end of the first capacitor fluctuates in the form of a sine wave, that is, the capacitor voltage at one end of the first capacitor includes a positive peak voltage and a negative peak voltage. Therefore, the control module can use the capacitor voltage at one end of the first capacitor at the current moment as one of the peak voltages when the current direction changes in a predetermined manner to determine the voltage amplitude corresponding to the first capacitor.

[0043] In some embodiments, Figure 5 As shown, the direction signal includes a first direction signal and a second direction signal. Based on the direction signal and the voltage signal, the method for determining the voltage amplitude of the first capacitor can be implemented by the following steps:

[0044] Step S121: when the acquired direction signal is converted from the second direction signal to the first direction signal, the voltage signal at the current moment is acquired as a first peak signal.

[0045] Step S122: when the acquired direction signal is converted from the first direction signal to the second direction signal, the voltage signal at the current moment is acquired as a second peak signal.

[0046] In the embodiment of the present application, the control module can divide the direction signal into a first direction signal and a second direction signal according to the actual direction of the current in the circuit, which are respectively used to characterize the different directions of the current flowing through the first resistor. For example, the first direction signal can characterize that the current flows from the first end of the first resistor to the second end of the first resistor, and then the second direction signal is used to characterize that the current flows from the second end of the first resistor to the first end of the first resistor. From the above analysis, it can be seen that when the direction signal received by the control module changes, the capacitor voltage at one end of the first capacitor just reaches the peak value. At the same time, since the capacitor voltage fluctuates in the form of a sine wave, the capacitor voltage includes two different positive and negative peak voltages. Therefore, the control module can use the voltage signal at the current moment as the first peak signal when the direction signal is converted from the second direction signal to the first direction signal, and use the voltage signal at the current moment as the second peak signal when the direction signal is converted from the first direction signal to the second direction signal. Thus, the control module can obtain the peak signals corresponding to the two different peak voltages corresponding to the capacitor voltage of the first capacitor, which are used to determine the voltage amplitude corresponding to the first capacitor.

[0047] Step S123: determining a voltage amplitude of the first capacitor based on the first peak signal and the second peak signal.

[0048] In an embodiment of the present application, after determining the first peak signal and the second peak signal, the control module can use the absolute value of the difference between the first peak signal and the second peak signal as the voltage amplitude corresponding to the first capacitor. Obviously, the first peak signal and the second peak signal are signals with opposite directions. Because the current flowing through the first resistor changes direction differently, the capacitor voltage at one end of the first capacitor is also at different peak values ​​accordingly. The control module can determine the voltage amplitude of the first capacitor based on the two peak signals with opposite directions.

[0049] In some implementations, the control module may use the absolute value of the difference between the first peak signal and the second peak signal as the voltage amplitude of the first capacitor.

[0050] Step S130: Based on a comparison result of the voltage amplitude and a target amplitude corresponding to a current heating power of the wireless heating device, controlling the heating power of the wireless heating device.

[0051] In the embodiment of the present application, the control module can determine the target amplitude based on the current heating power, that is, when the material of the pot carried is an ideal material, the voltage amplitude of the first capacitor in the circuit is used as the target amplitude when the wireless heating device is heated at the current heating power. At the same time, in order to protect the circuit, the control module can also determine the actual voltage amplitude at one end of the first capacitor when heating at the current heating power through the above steps, and compare the actual voltage amplitude with the expected target amplitude, thereby determining whether the material of the pot carried by the wireless heating device has changed at this time.

[0052] In some embodiments, Figure 6 As shown, the control module controls the heating power of the wireless heating device based on the comparison result of the voltage amplitude and the target amplitude corresponding to the current heating power of the wireless heating device, which can be achieved by the following steps:

[0053] Step S131: if the voltage amplitude is greater than the target amplitude, reducing the heating power of the wireless heating device.

[0054] Step S132: If the voltage amplitude is less than or equal to the target amplitude, the current heating power of the wireless heating device is kept unchanged.

[0055] In the embodiment of the present application, if the actual voltage amplitude corresponding to the first capacitor in the circuit of the wireless heating device is greater than the target amplitude, it indicates that the material of the pot carried at this time has deteriorated. At this time, the user may move the pot away from the wireless heating device, or the user may replace the original pot. In short, the heating power absorbed by the pot becomes less, resulting in a larger current in the wireless heating device. If the heating power is not changed at this time, the larger current is likely to damage the circuit components. Therefore, in this case, the control module can reduce the heating power of the wireless heating device to reduce the current in the circuit and protect the circuit components. In another case, that is, the voltage amplitude is less than or equal to the target amplitude, at this time, the material of the pot carried by the wireless heating device has improved. It may be that the user has reduced the distance between the pot and the wireless heating device, or the user has replaced a pot with a better material. In short, the heating power absorbed by the pot becomes larger, and the current in the wireless heating device may become smaller. At this time, it will not affect the safety of the circuit components. At the same time, the heating power absorbed by the pot becomes larger, and the heating effect on the pot will be better. Therefore, the control module does not need to change the heating power at this time, that is, keep the current heating power of the wireless heating device unchanged.

[0056] In some embodiments, if the actual voltage amplitude corresponding to the first capacitor in the circuit of the wireless heating device is greater than the target amplitude, the control module can determine the reduction in the heating power of the wireless heating device based on the difference between the voltage amplitude and the target amplitude. In other words, when the voltage amplitude is greater than the target amplitude, the greater the difference between the voltage amplitude and the target amplitude, the greater the reduction in the heating power of the wireless heating device by the control module. Of course, the reduction in heating power needs to be kept within a preset safety range. If it exceeds this preset safety range, the control module can output a warning message to inform the user that the pot carried at this time cannot be heated.

[0057] The power control method provided in the embodiment of the present application determines the voltage amplitude of the first capacitor by acquiring a direction signal for characterizing the direction of the current flowing through the first resistor and a voltage signal for characterizing the capacitor voltage of the first capacitor, and then controls the heating power of the wireless heating device based on the comparison result of the voltage amplitude and the target amplitude corresponding to the current heating power of the wireless heating device. The material change of the carried pot during the heating process is judged by the relationship between the voltage amplitude at one end of the first capacitor that changes in real time and the target amplitude corresponding to the current heating power, and then the heating power of the wireless heating device is adjusted in real time to determine that the current in the wireless heating device is always within a safe range, so as to achieve the effect of protecting the wireless heating device.

[0058] See also Figure 7 , which shows a wireless heating device 200 provided in an embodiment of the present application, including a heating coil, a first resistor R1, a first capacitor C1 and a power control circuit 100 provided in the above embodiment. Among them, the heating coil, the first resistor R1 and the first capacitor C1 are connected in series in sequence. The power control circuit 100 can obtain a direction signal for characterizing the direction of the current flowing through the first resistor R1, and a voltage signal for characterizing the capacitor voltage of the first capacitor C1, and determine the voltage amplitude of the first capacitor C1 based on the direction signal and the voltage signal, and then judge the change of the material of the pot during the heating process based on the comparison result of the voltage amplitude and the target amplitude corresponding to the current heating power of the wireless heating device 200, and then adjust the heating power of the wireless heating device 200 in real time to ensure that the current in the wireless heating device 200 is always within a safe range, so as to achieve the effect of protecting the wireless heating device 200.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A power control circuit, characterized in that: The power control circuit is applied to a wireless heating device, which is used to heat a carried pot. The wireless heating device comprises a heating coil, a first resistor and a first capacitor, which are connected in series in sequence. The power control circuit comprises: A direction detection module, connected to both ends of the first resistor, and configured to detect a direction of a current flowing through the first resistor; A voltage detection module, connected to one end of the first capacitor, and configured to detect a capacitor voltage of the first capacitor; A control module is connected to the direction detection module and the voltage detection module. The control module is used to determine the voltage amplitude of the first capacitor based on the direction signal corresponding to the current direction input by the direction detection module and the voltage signal corresponding to the capacitor voltage input by the voltage detection module, and control the heating power of the wireless heating device based on the comparison result of the voltage amplitude with the target amplitude corresponding to the current heating power of the wireless heating device.

2. The power control circuit according to claim 1, characterized in that: The control module is used to reduce the heating power of the wireless heating device when the voltage amplitude is greater than the target amplitude, and to keep the current heating power of the wireless heating device unchanged when the voltage amplitude is less than or equal to the target amplitude.

3. The power control circuit according to claim 1, characterized in that: The direction signal includes a first direction signal and a second direction signal, and the control module is used to use the voltage signal at the current moment as the first peak signal when the received direction signal is converted from the second direction signal to the first direction signal, and to use the voltage signal at the current moment as the second peak signal when the received direction signal is converted from the first direction signal to the second direction signal; The control module is further configured to determine a voltage amplitude of the first capacitor based on the first peak signal and the second peak signal.

4. The power control circuit according to claim 3, characterized in that: The control module is further configured to determine an absolute value of a difference between the first peak signal and the second peak signal, and use the absolute value as the voltage amplitude.

5. The power control circuit according to any one of claims 1 to 4, characterized in that: The direction detection module comprises a first detection port, a second detection port and a first output port, the first detection port is connected to the first end of the first resistor, the second detection port is connected to the second end of the first resistor, and the first output port is connected to the first input port of the control module; The direction detection module is used to obtain a first voltage at a first end of the first resistor through the first detection port, and to obtain a second voltage at a second end of the first resistor through the second detection port; The direction detection module is further used to output different direction signals to the first input port through the first output port according to the comparison result of the first voltage and the second voltage, and the direction signal is used to represent the direction of the current flowing through the first resistor.

6. The power control circuit according to any one of claims 1 to 4, characterized in that: The voltage detection module comprises a third detection port and a second output port, the third detection port is connected to one end of the first capacitor, and the second output port is connected to the second input port of the control module; The voltage detection module is used to obtain the capacitor voltage of the first capacitor through the third detection port, and transmit the voltage signal corresponding to the capacitor voltage to the second input port through the second output port.

7. A power control method, characterized in that: Applied to a wireless heating device, the wireless heating device is used to heat a carried cookware, the wireless heating device comprises a heating coil and a first resistor and a first capacitor connected in series to the heating coil, the method comprises: Acquire a direction signal and a voltage signal, wherein the direction signal is used to characterize the direction of the current flowing through the first resistor, and the voltage signal is used to characterize the capacitance voltage of the first capacitor; Determining a voltage amplitude of the first capacitor based on the direction signal and the voltage signal; Based on a comparison result of the voltage amplitude and a target amplitude corresponding to a current heating power of the wireless heating device, the heating power of the wireless heating device is controlled.

8. The method according to claim 7, characterized in that The controlling the heating power of the wireless heating device based on the comparison result of the voltage amplitude and the target amplitude corresponding to the current heating power of the wireless heating device comprises: If the voltage amplitude is greater than the target amplitude, reducing the heating power of the wireless heating device; If the voltage amplitude is less than or equal to the target amplitude, the current heating power of the wireless heating device is kept unchanged.

9. The method according to claim 7, characterized in that: The direction signal includes a first direction signal and a second direction signal, and determining the voltage amplitude of the first capacitor based on the direction signal and the voltage signal includes: When the acquired direction signal is converted from the second direction signal to the first direction signal, acquiring the voltage signal at the current moment as a first peak signal; When the acquired direction signal is converted from the first direction signal to the second direction signal, acquiring the voltage signal at the current moment as a second peak signal; A voltage amplitude of the first capacitor is determined based on the first peak signal and the second peak signal.

10. A wireless heating device, characterized in that: The wireless heating device comprises a heating coil, a first resistor, a first capacitor and a power control circuit as described in any one of claims 1 to 6, wherein the heating coil, the first resistor and the first capacitor are connected in series in sequence.

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