CN214375922U - Control circuit of electromagnetic cooking utensil - Google Patents

Abstract

The application discloses control circuit of electromagnetic cooking utensil, include the load, carry out the rectification module of rectification, carry out the module of making an uproar that falls of filtering to the pulsating direct current after the rectification to external power supply to and the module of making an uproar establishes ties and is used for controlling the switch module that the module of making an uproar inserts that falls with falling the module of making an uproar, control circuit still includes: the zero-crossing detection module is used for detecting a zero-crossing signal of the external power supply; the voltage detection module is electrically connected with the noise reduction module so as to acquire a voltage signal of the noise reduction module; and the control module is respectively connected with the load, the switch module, the zero-crossing detection module and the voltage detection module so as to control the switch module to be switched on and off and the load to be switched on and off according to the acquired zero-crossing signal and the acquired voltage signal. The application can prevent the instantaneous heavy current generated in the charging and discharging process of the noise reduction module from impacting the front and rear electrical elements connected with the noise reduction module to a great extent.

Description

Control circuit of electromagnetic cooking utensil

Technical Field

The utility model belongs to the technical field of domestic appliance, especially, relate to an electromagnetic cooking utensil's control circuit.

Background

Electromagnetic cooking utensil is because the mode through electromagnetic induction cooks food, and it is efficient to generate heat, and convenient to use safety, convenient to carry simultaneously easily uses, as long as there is the place of power all to use, compares with traditional firing equipment and has very big advantage, has been used by more and more people.

Specifically, because the high-frequency excitation coil inside the electromagnetic cooking utensil can generate an alternating magnetic field after being introduced with alternating current, when the metal cookware is placed on the surface of the electromagnetic cooking utensil, the surface of the cookware can cut the magnetic lines of force of the alternating magnetic field to generate a large amount of eddy currents at the bottom of the cookware, the eddy currents enable carriers at the bottom of the cookware to move irregularly at high speed, and the carriers collide with atoms and rub to generate heat energy, so that the purpose of heating food is achieved. However, the existing electromagnetic cooking appliances are often accompanied by buzzing noise during heating, and the noise becomes larger as the heating power increases, especially when water is boiled, thereby seriously affecting the use experience of users.

Through experimental analysis, the skilled person finds that the main components of the noise are low-frequency noise of 100Hz and resonance frequency (100Hz integer times frequency) noise, and the noise in the frequency range just falls within the frequency range of human auditory sense (the frequency range of human auditory sense is 20-20000 Hz). The noise is generated because the power frequency alternating current in China is 50Hz, and when the power frequency alternating current of 50Hz passes through a rectifying circuit in the electromagnetic cooking appliance, the power frequency alternating current can output pulsating direct current with the frequency of 100Hz and the peak voltage of 310V. Further, when an IGBT (Insulated Gate Bipolar Transistor) in the electromagnetic cooking appliance operates at an operating frequency (e.g., 20 to 35kHz), an envelope voltage difference formed by a pulsating direct current of 100Hz can reach 970V. This kind of envelope pressure differential has very big amplitude energy, and it can be along with electromagnetic cooking utensil's resonant frequency and act on the metal pan to make the pan produce a large amount of lorentz forces, and then produce above-mentioned noise.

In order to reduce noise generated during the operation of the electromagnetic cooking appliance, in the prior art, a capacitor is arranged in a control circuit of the electromagnetic cooking appliance to reduce an envelope voltage difference generated by an IGBT therein, so as to reduce amplitude energy of pulsating direct current. Although the purpose of noise reduction can be achieved to a certain extent by the aid of the arrangement, a large instantaneous current can be released in the charging and discharging process of the capacitor, so that damage to a front-end rectifying module of the control circuit or a rear-end component connected with the capacitor can be caused, and the control circuit in the electromagnetic cooking appliance is not safe and stable in operation.

It will thus be seen that the prior art is susceptible to further improvements and enhancements.

SUMMERY OF THE UTILITY MODEL

The utility model provides a control circuit of electromagnetic cooking utensil to solve above-mentioned technical problem's at least one technical problem.

The utility model discloses the technical scheme who adopts does:

the utility model provides an electromagnetic cooking utensil's control circuit, include the load, carry out the rectification module of rectification, carry out the module of making an uproar that falls of filtering to the pulsation direct current after the rectification to external power supply, and with it establishes ties and is used for control to fall the module of making an uproar the switch module that the module of making an uproar inserted, control circuit still includes: the zero-crossing detection module is used for detecting a zero-crossing signal of the external power supply; the voltage detection module is electrically connected with the noise reduction module so as to acquire a voltage signal of the noise reduction module; and the control module is respectively connected with the load, the switch module, the zero-crossing detection module and the voltage detection module, and is used for controlling the on-off of the switch module and the on-off of the load according to the acquired zero-crossing signal and the acquired voltage signal.

As a preferred embodiment of the present invention, the zero-crossing detection module includes a transient suppression unit, a first diode, an RC filtering unit, and a voltage stabilization unit; the input end of the transient suppression unit is connected with the external power supply, and the output end of the transient suppression unit is connected with the anode of the first diode; the negative electrode of the first diode is connected with the input end of the RC filtering unit, the output end of the RC filtering unit is connected with the input end of the voltage stabilizing unit, and the output end of the voltage stabilizing unit is connected with the control module.

As a preferred embodiment of the present invention, the transient suppression unit includes a second diode and a third diode; the second diode is connected with a live wire leading-out end of the external power supply, the negative electrode of the second diode is connected with the negative electrode of the third diode, and the positive electrode of the third diode is connected with a zero line leading-out end of the external power supply.

As a preferred embodiment of the present invention, the RC filtering unit includes: the circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor and a first capacitor connected with the fourth resistor in parallel, wherein the first resistor, the second resistor, the third resistor and the fourth resistor are connected in sequence.

As a preferred embodiment of the present invention, the voltage stabilizing unit includes a voltage stabilizing diode and a second capacitor connected in parallel.

As a preferred embodiment of the present invention, the voltage detection module includes a first voltage-dividing resistor, a second voltage-dividing resistor, a third voltage-dividing resistor and a fourth voltage-dividing resistor connected in series in sequence.

As a preferred embodiment of the present invention, the switch module includes an access switch, a follow current unit and an amplifying unit; the first contact of the access switch is connected with the output end of the rectification module, the second contact of the access switch is connected with the input end of the noise reduction module, and the access switch is connected with the follow current unit; one end of the amplifying unit is connected with the follow current unit, and the other end of the amplifying unit is connected with the control module.

As a preferred embodiment of the present invention, the freewheel unit includes a fifth resistor, a sixth resistor and a freewheel diode, and the fifth resistor and the sixth resistor are connected in parallel and then connected in series with the freewheel diode.

As a preferred embodiment of the present invention, the amplifying unit includes: the triode, the seventh resistor and the eighth resistor; and the collector of the triode is connected with the follow current unit, the base and the emitter of the triode are connected in parallel with a seventh resistor, and the triode and the seventh resistor are connected in parallel and then connected in series with the eighth resistor.

As a preferred embodiment of the present invention, the control circuit further includes a temperature detection module, the temperature detection module is connected to the control module for detecting the temperature of the electromagnetic cooking device, and when the temperature of the electromagnetic cooking device reaches a preset value, the control module controls the switch module to switch on.

Since the technical scheme is used, the utility model discloses the beneficial effect who gains does:

1. the utility model provides an electromagnetic cooking utensil's control circuit, include rectifier module, fall the module of making an uproar, switch module, zero cross detection module, voltage detection module and control module. Specifically, the control module can carry out real-time control to switch module and load according to the voltage signal of zero-crossing signal and noise reduction module, when the voltage signal zero crossing of noise reduction module, make its access control circuit can to a great extent prevent that the instantaneous heavy current that noise reduction module charge-discharge in-process produced from causing the impact to the front and back end electrical components that are connected with noise reduction module, avoid electrical components's damage to promote control circuit's stability. In addition, the control module in this embodiment can control the on/off of the load according to the voltage change of the noise reduction module, and transfer the overvoltage to the load, thereby preventing voltage impact caused by charging and discharging of the noise reduction module, and further improving the stability of the control circuit.

2. As a preferred embodiment of the present invention, the transient suppression unit can prevent the interference of overvoltage, surge, lightning strike, etc. to the control circuit, and improve the stability of the control circuit; the RC filtering unit can play a role in smoothing signals or voltages, and compared with other filtering structures, the RC filtering unit is lower in cost; the first diode and the voltage stabilizing unit can play a role in filtering and stabilizing voltage, so that smooth operation of the control circuit is further facilitated.

3. As a preferred embodiment of the utility model, the setting of afterflow unit can be when switch module is in the off-state in the switch module, and the release falls the energy of storing in the access switch (like the relay), prevents to puncture the triode in the amplification unit because of the induced voltage of relay is too high to do benefit to the life who promotes the amplification unit, promote switch module's operating stability and security.

4. As an embodiment of the present invention, the temperature detection module can control the access of the noise reduction unit according to a reasonable temperature range, for example, when the electromagnetic cooking device is at 60 ℃ -90 ℃, the noise thereof is maximum, and the access of the noise reduction unit not only can reduce the noise of the electromagnetic cooking device to the maximum extent, but also can save the energy consumption of the electromagnetic cooking device. Moreover, the selective access mode of the noise reduction unit is beneficial to prolonging the service life of the noise reduction unit, so that the later maintenance cost of the product is reduced, and the use experience of a user is improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the application and not to limit the invention. In the drawings:

fig. 1 is a schematic structural diagram of a control circuit according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of another control circuit provided in an embodiment of the present invention;

fig. 3 is a circuit structure diagram of a zero-crossing detection module according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of another control circuit according to an embodiment of the present invention;

fig. 5 is a circuit structure diagram of a switch module according to an embodiment of the present invention;

fig. 6 is a schematic flow chart of a working process of an electromagnetic cooking appliance according to an embodiment of the present invention.

The device comprises a 100 load, a 200 rectifying module, a 300 noise reduction module, a 400 switching module, a 410 freewheeling unit, a 420 amplifying unit, a 500 zero-crossing detection module, a 510 transient suppression unit, a 520RC filtering unit, a 530 voltage stabilizing unit, a 600 voltage detection module and a 700 control module.

Detailed Description

In order to more clearly explain the overall concept of the present application, the following detailed description is given by way of example in conjunction with the accompanying drawings.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

In addition, in the description of the present invention, it is to be understood that the terms "top," "bottom," "inner," "outer," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present invention and to simplify the description, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; the connection can be mechanical connection, electrical connection or communication; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

As shown in fig. 1, the utility model provides a control circuit of electromagnetic cooking utensil, it includes load 100, carries out the rectifier module 200 of rectification to external power, carries out the noise reduction module 300 of filtering to the pulsating direct current after rectifying, and with noise reduction module 300 establishes ties and is used for control the switch module 400 that noise reduction module 300 accessed. In addition, the control circuit may also include a zero crossing detection module 500, a voltage detection module 600, and a control module 700.

The zero-crossing detection module 500 is configured to detect a zero-crossing signal of the external power supply; the voltage detection module 600 is electrically connected to the noise reduction module 300 to collect a voltage signal of the noise reduction module 300; the control module 700 is respectively connected to the load 100, the switch module 400, the zero-cross detection module 500 and the voltage detection module 600, so as to control the on/off of the switch module 400 and the on/off of the load 100 according to the acquired zero-cross signal and the acquired voltage signal. In addition, the control module 700 may be a single chip, a CPU, an FPGA (Field Programmable Gate Array), a CPLD (Complex Programmable logic device), and the like, and the type of the control module 700 is not limited in this embodiment.

The load 100 in the present embodiment may be, for example, an electromagnetic induction coil or other energy consuming components provided inside an electromagnetic cooking appliance, and the specific structure and type of the load 100 are not limited in the present embodiment. In addition, the rectifying unit 100 in the present application is connected to an external power supply for converting ac power into pulsating dc power, and the present embodiment is not limited to a specific type and structure of the rectifying module 200, and may be, for example, a full-wave rectifying unit, a bridge rectifying unit, or even a half-wave rectifying unit if no power is required. As to which type of rectifier module 200 should be selected, the design requirements, the use characteristics, the production cost, the stability, and the like of the product should be considered comprehensively.

Preferably, referring to fig. 2, the noise reduction module 300 may be an electrolytic capacitor, and the capacitance value of the electrolytic capacitor ranges from 100 μ F to 1000 μ F, and when the capacitance value of the electrolytic capacitor is in the above range, the electromagnetic cooking appliance has less noise. In addition, the noise reduction unit 400 in this embodiment may be of various types, and besides the electrolytic capacitor, for example, a mica capacitor, a ceramic capacitor, and the like may also be used, which is not limited in this embodiment. However, for ease of understanding and description, the following disclosure of the present application is made by taking the case where the noise reduction module 300 is an electrolytic capacitor as an example.

Specifically, when the capacitance value of the connected electrolytic capacitor is greater than 100 muF, the noise of the electromagnetic cooking appliance in an actual test is already improved, and the larger the capacitance value of the electrolytic capacitor is, the more obvious the noise improvement is; when the capacity value reaches 330 muF, the electromagnetic noise is obviously improved; when the capacity value reaches 680 mu F, the noise of the electromagnetic cooking appliance is greatly eliminated; when the capacity value reaches 1000 muF, the noise of the electromagnetic cooking utensil is basically eliminated.

The utility model provides an electromagnetic cooking utensil's control circuit, control module 700 can carry out real time control to switch module 400 and load 100 according to zero cross signal and the voltage signal of the module 300 of making an uproar that falls, when the voltage signal zero crossing of the module 300 of making an uproar falls, make its access control circuit can to a great extent prevent to fall the instantaneous heavy current that the module 300 of making an uproar charge-discharge in-process produced and cause the impact to the front and back end electrical components that are connected with the module 300 of making an uproar, avoid electrical components's damage, thereby promote control circuit's stability. In addition, the control module 700 in this embodiment may perform on-off control on the load 100 according to the voltage variation of the noise reduction module 300, and transfer the overvoltage to the load 100, so as to prevent voltage impact caused by charging and discharging of the noise reduction module 300, and further improve the stability of the control circuit.

As a preferred embodiment of the present invention, referring to fig. 3, the zero-crossing detection module 500 may include, for example, a transient suppression unit 510, a first diode D1, an RC filtering unit 520, and a voltage stabilization unit 530. The input end of the transient suppression unit 510 is connected to the external power supply, and the output end is connected to the anode of the first diode D1; the cathode of the first diode D1 is connected to the input of the RC filter unit 520, the output of the RC filter unit 520 is connected to the input of the voltage regulator unit 530, and the output of the voltage regulator unit 530 is connected to the control module 700.

Further, the transient suppression unit 510 may include, for example, a second diode D2 and a third diode D3. The second diode D2 is connected with a live wire leading-out end of the external power supply, the negative electrode of the second diode D2 is connected with the negative electrode of the third diode D3, and the positive electrode of the third diode D3 is connected with a zero wire leading-out end of the external power supply. The transient suppression unit 510 can prevent the interference of overvoltage, surge, lightning strike and the like to the control circuit, and improve the stability of the control circuit.

The RC filtering unit 520 may include, for example, a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4 connected in sequence, and a first capacitor C1 connected in parallel with the fourth resistor R4. The RC filter unit 520 can smooth signals or voltages, and the RC filter unit 520 has lower cost compared to other filter structures. In addition, the voltage regulation unit 530 may include a voltage regulation diode D4 and a second capacitor C2 connected in parallel, for example, and the first diode D1 and the voltage regulation unit 530 are configured to perform filtering and voltage regulation, thereby further facilitating smooth operation of the control circuit.

As a preferred embodiment of the present invention, referring to fig. 4, the voltage detection module 600 may include a first voltage dividing resistor RS1, a second voltage dividing resistor RS2, a third voltage dividing resistor RS3, and a fourth voltage dividing resistor RS4 connected in series. The mode that a plurality of divider resistors are connected in series can avoid the current that enters the voltage detection module 600 to be too big to realize the safe and stable detection to the voltage value of the noise reduction module 300.

As a preferred embodiment of the present invention, referring to fig. 5, the switch module 400 may include an access switch K1, a freewheeling unit 410, and an amplifying unit 420; wherein the first contact J1 of the access switch K1 is connected to the output terminal of the rectifying module 200, the second contact J2 of the access switch K1 is connected to the input terminal of the noise reduction module 300, and the access switch K1 is connected to the freewheeling unit 410; one end of the amplifying unit 420 is connected to the freewheeling unit 410, and the other end is connected to the control module 700.

Further, the freewheel unit 410 may include, for example, a fifth resistor R5, a sixth resistor R6, and a freewheel diode D5, and the fifth resistor and the sixth resistor are connected in parallel and then connected in series with the freewheel diode. The flywheel unit 410 is configured to release the energy stored in the access switch K1 (such as a relay) when the switch module 400 is in an off state, so as to prevent the triode in the amplifying unit 420 from being broken down due to an excessively high induced voltage of the relay, thereby facilitating the improvement of the service life of the amplifying unit 420 and the operation stability and safety of the switch module 400. Besides, the access switch K1 may be a relay, a thyristor, a MOS transistor (field effect transistor), or the like, and the type of the access switch K1 is not limited in this embodiment.

In a specific example, the amplifying unit 420 may include, for example: a triode Q1, a seventh resistor R7 and an eighth resistor R8; the collector of the triode Q1 is connected with the freewheeling unit 410, the base and the emitter of the triode Q1 are connected in parallel with a seventh resistor R7, and the triode Q1 and the seventh resistor R7 are connected in parallel and then connected in series with the eighth resistor R8.

In one embodiment, the control circuit may further include a temperature detection module (not shown in the figure), which is connected to the control module 700 and is configured to detect the temperature of the electromagnetic cooking appliance, and the control module 700 controls the switch module 400 to be turned on when the temperature of the electromagnetic cooking appliance reaches a preset value.

In order to fully understand the working process of the electromagnetic cooking appliance provided by the embodiment, reference may be made to fig. 6 and the following steps:

s1, heating is started.

And S2, judging whether the temperature of the electromagnetic cooking appliance reaches a preset value. If yes, go to step S3; if not, step S4 is executed.

And S3, judging whether the voltage signal of the noise reduction unit crosses zero. If yes, go to step S5; if not, step S7 is executed.

And S4, the switch module is turned off.

S5, the load is turned off and the switch module is turned on.

And S6, judging whether the voltage of the noise reduction unit reaches a threshold value. If yes, go to step S7; if not, step S8 is executed.

And S7, starting the load.

And S8, finishing heating.

In the above working process of the electromagnetic cooking appliance, when the heating temperature is not within the preset range, the control module 700 controls the load 100 to be started and the switch module 400 to be switched off, so that the electromagnetic cooking appliance continues to heat; when the heating temperature reaches a preset range and the zero-crossing detection module 500 detects a zero-crossing point of a voltage signal, the control module 700 can control the load 100 to be turned off and the switch module 400 to be turned on, so that the noise reduction module 300 is connected to the control circuit; when the heating temperature of the electromagnetic cooking appliance reaches a preset range and the voltage signal is not beyond a zero point, the control module 700 controls the load 100 to be started and the switch module 400 to be switched off, so that the electromagnetic cooking appliance continues to heat; when the heating temperature of the electromagnetic cooking appliance reaches a preset range, a voltage signal crosses zero, and the voltage value of the noise reduction module 300 detected by the voltage detection module 600 is greater than a threshold value, the control module 700 controls the load 100 to be started and the switch module 400 to be switched on, so that the noise reduction module 300 is connected to the control circuit, and the electromagnetic cooking appliance continues to be heated; when the heating temperature of the electromagnetic cooker reaches a preset range and the voltage signal crosses zero, but the voltage value of the noise reduction module 300 detected by the voltage detection module 600 is not greater than the threshold, the heating process is ended.

It should be noted that the preset value of the heating temperature of the electromagnetic cooking appliance is not limited in this embodiment, but in actual tests, the noise of the electromagnetic cooking appliance is found to be the largest when the water is boiled in a certain temperature range (T1-T2), specifically, T1 is generally around 60 ℃, and T2 is generally around 90 ℃. Therefore, the preset temperature value in this embodiment may be in a temperature range of 60 ℃ to 90 ℃, or may be a specific value (e.g., 75 ℃). The voltage threshold of the noise reduction unit may be 200V, 150V, 300V, or the like, which is not limited in this embodiment.

The setting of temperature detection module in this application can make electromagnetic cooking utensil can not only save electromagnetic cooking utensil's energy consumption according to the access of reasonable temperature range control noise reduction unit, and this kind of selective access mode of noise reduction unit does benefit to the extension of its self life-span moreover to reduce the later maintenance cost of product, promote user's use and experience.

The utility model can be realized by adopting or using the prior art for reference in places which are not mentioned in the utility model.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments.

The above description is only an example of the present invention, and is not intended to limit the present invention. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims (10)

1. The utility model provides a control circuit of electromagnetic cooking utensil, includes the load, carries out the rectifier module of rectification to external power supply, carries out the noise reduction module of filtering to the pulsating direct current after rectifying, and with the noise reduction module is established ties and is used for controlling the switch module that the module of making an uproar inserts, its characterized in that, control circuit still includes:

the zero-crossing detection module is used for detecting a zero-crossing signal of the external power supply;

the voltage detection module is electrically connected with the noise reduction module so as to acquire a voltage signal of the noise reduction module;

and the control module is respectively connected with the load, the switch module, the zero-crossing detection module and the voltage detection module, and is used for controlling the on-off of the switch module and the on-off of the load according to the acquired zero-crossing signal and the acquired voltage signal.

2. The control circuit of claim 1, wherein the zero-crossing detection module comprises a transient suppression unit, a first diode, an RC filtering unit, and a voltage stabilization unit; wherein,

the input end of the transient suppression unit is connected with the external power supply, and the output end of the transient suppression unit is connected with the anode of the first diode;

the negative electrode of the first diode is connected with the input end of the RC filtering unit, the output end of the RC filtering unit is connected with the input end of the voltage stabilizing unit, and the output end of the voltage stabilizing unit is connected with the control module.

3. The control circuit of claim 2, wherein the transient suppression unit includes a second diode and a third diode;

the second diode is connected with a live wire leading-out end of the external power supply, the negative electrode of the second diode is connected with the negative electrode of the third diode, and the positive electrode of the third diode is connected with a zero line leading-out end of the external power supply.

4. The control circuit of claim 2, wherein the RC filtering unit comprises: the circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor and a first capacitor connected with the fourth resistor in parallel, wherein the first resistor, the second resistor, the third resistor and the fourth resistor are connected in sequence.

5. The control circuit of claim 2, wherein the voltage regulator block comprises a zener diode and a second capacitor connected in parallel.

6. The control circuit of claim 1, wherein the voltage detection module comprises a first voltage dividing resistor, a second voltage dividing resistor, a third voltage dividing resistor and a fourth voltage dividing resistor connected in series in sequence.

7. The control circuit of claim 1, wherein the switching module includes an access switch, a freewheeling unit, and an amplification unit; wherein,

a first contact of the access switch is connected with the output end of the rectification module, a second contact of the access switch is connected with the input end of the noise reduction module, and the access switch is connected with the follow current unit;

one end of the amplifying unit is connected with the follow current unit, and the other end of the amplifying unit is connected with the control module.

8. The control circuit according to claim 7, wherein the freewheeling unit comprises a fifth resistor, a sixth resistor and a freewheeling diode, and the fifth resistor and the sixth resistor are connected in parallel and then connected in series with the freewheeling diode.

9. The control circuit of claim 7, wherein the amplification unit comprises: the triode, the seventh resistor and the eighth resistor; and the collector of the triode is connected with the follow current unit, the base and the emitter of the triode are connected in parallel with a seventh resistor, and the triode and the seventh resistor are connected in parallel and then connected in series with the eighth resistor.

10. The control circuit according to any one of claims 1 to 9, further comprising a temperature detection module, wherein the temperature detection module is connected to the control module and is configured to detect a temperature of the electromagnetic cooking appliance, and the control module controls the switch module to be turned on when the temperature of the electromagnetic cooking appliance reaches a preset value.

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