Power control circuit and heating equipment

Abstract

The utility model provides a power control circuit and a heating device. The power control circuit comprises an inductive module, a capacitive module, a current limiting module, a first switch module and a control module. The first end of the inductive module is connected with the first end of an input power supply, the second end of the inductive module is connected with the first end of the current limiting module and the first end of the heating module, the second end of the current limiting module is connected with the first end of the capacitive module, and the second end of the heating module is connected with the first end of the first switch module. The second end of the first switch module is connected with the second end of the capacitive module and the second end of the input power supply. The driving end of the first switch module is connected with the first end of the control module. The power control circuit can reduce the cost of power control.

Description

Technical Field

[0001] The embodiments of the present utility model relate to the technical field of electronic circuits, and particularly to a power control circuit and a heating device. Background Art

[0002] New energy water heaters refer to devices that use new renewable energy or high-efficiency energy for heating, such as solar energy, geothermal energy, etc. These heaters are usually designed with the concept of environmental protection and energy conservation to replace traditional heating devices that use fossil energy. New energy water heaters can reduce dependence on traditional energy, reduce energy consumption, and reduce environmental pollution, etc.

[0003] The existing power control method of new energy water heaters mainly controls the power by dividing the heating elements into multiple groups with different gears. For example, in the first gear, the first group of heating elements is turned on for heating, in the second gear, the second group of heating elements is turned on for heating, in the third gear, the third group of heating elements is turned on for heating, and in the fourth gear, the first and second groups of heating elements are turned on simultaneously for heating. However, this power control method requires multiple switching tubes and has a high cost. Summary of the Utility Model

[0004] The embodiments of the present utility model provide a power control circuit and a heating device, which can reduce the cost of power control.

[0005] In a first aspect, the embodiments of the present utility model provide a power control circuit applied to a heating device. The heating device includes a heating module for generating heat. The power control circuit includes an inductive module, a capacitive module, a current limiting module, a first switching module, and a control module. The first end of the inductive module is used to connect the first end of an input power supply. The second end of the inductive module is respectively connected to the first end of the current limiting module and the first end of the heating module. The second end of the current limiting module is connected to the first end of the capacitive module. The second end of the heating module is connected to the first end of the first switching module. The second end of the first switching module is respectively connected to the second end of the capacitive module and the second end of the input power supply. The driving end of the first switching module is connected to the first end of the control module. Among them, the control module is used to output a first pulse width modulation signal to the first switching module. The first switching module is used to alternately turn on and off according to the first pulse width modulation signal to control the heating power of the heating module. The inductive module is used to suppress the peak current generated by the power control circuit when the first switching module is turned on. The capacitive module is used to absorb the peak voltage generated by the power control circuit when the first switching module is turned off. The current limiting module is used to limit the charging and discharging current of the capacitive module.

[0006] In some embodiments, the power control circuit further includes a voltage acquisition module. The voltage acquisition module is respectively connected to the input power supply and the second end of the control module. The voltage acquisition module is configured to divide the voltage of the input power supply and output a divided voltage signal to the control module.

[0007] In some embodiments, the voltage acquisition module includes a resistor R5 and a resistor R6. The first end of the resistor R5 is respectively connected to the first end of the input power supply and the first end of the inductive module. The second end of the resistor R5 is respectively connected to the second end of the control module and the first end of the resistor R6. The second end of the resistor R6 is connected to the second end of the input power supply.

[0008] In some embodiments, the power control circuit further includes a sampling resistor. The first end of the sampling resistor is respectively connected to the second end of the first switch module and the third end of the control module. The second end of the sampling resistor is respectively connected to the fourth end of the control module, the second end of the capacitive module, and the second end of the input power supply.

[0009] In some embodiments, the inductive module includes a common mode inductor. The first end of the common mode inductor is configured to be connected to the first end of the input power supply. The second end of the common mode inductor is respectively connected to the first end of the current limiting module and the first end of the heating module. The third end of the common mode inductor is configured to be connected to the second end of the input power supply. The fourth end of the common mode inductor is connected to the second end of the capacitive module.

[0010] In some embodiments, the power control circuit further includes a diode. The anode of the diode is respectively connected to the second end of the inductive module, the first end of the current limiting module, and the first end of the heating module. The cathode of the diode is respectively connected to the second end of the current limiting module and the first end of the capacitive module.

[0011] In some embodiments, the power control circuit further includes a second switch module. The first end of the second switch module is respectively connected to the second end of the inductive module and the first end of the current limiting module. The second end of the second switch module is connected to the first end of the heating module. The driving end of the second switch module is connected to the fifth end of the control module. Wherein, the control module is further configured to output a second pulse width modulation signal to the second switch module to make the second switch module conduct or turn off alternately.

[0012] In some embodiments, the first switching module includes a first switching transistor and a first driving unit. A first end of the first switching transistor is connected to a first end of the heating module, a second end of the first switching transistor is connected to a second end of the capacitive module, a third end of the first switching transistor is connected to a first end of the first driving unit, and a second end of the first driving unit is connected to a first end of the control module.

[0013] In some embodiments, the second switching module includes a second switching transistor and a second driving unit. A first end of the second switching transistor is respectively connected to a second end of the inductive module and a first end of the current limiting module, a second end of the second switching transistor is connected to a first end of the heating module, a third end of the second switching module is connected to a first end of the second driving unit, and a second end of the second driving unit is connected to a fifth end of the control module.

[0014] In a second aspect, an embodiment of the present invention further provides a heating device, which includes a heating module for generating heat and a power control circuit as described in any one of the first aspects; the power control circuit is connected to the heating module.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: Different from the prior art, the present invention provides a power control circuit and a heating device. The power control circuit includes an inductive module, a capacitive module, a current limiting module, a first switching module and a control module. A first end of the inductive module is used to connect to a first end of an input power supply, a second end of the inductive module is respectively connected to a first end of the current limiting module and a first end of the heating module, a second end of the current limiting module is connected to a first end of the capacitive module, a second end of the heating module is connected to a first end of the first switching module, a second end of the first switching module is respectively connected to a second end of the capacitive module and a second end of the input power supply, and a driving end of the first switching module is connected to a first end of the control module. This power control circuit can adjust the power of the heating module by using the same set of switching modules, reducing the cost of power control. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In one or more embodiments, exemplary illustrations are provided through pictures in the corresponding drawings. These exemplary illustrations do not constitute limitations on the embodiments. Elements / modules and steps with the same reference numerals in the drawings represent similar elements / modules and steps. Unless otherwise stated, the drawings in the figures do not constitute a proportional limitation.

[0017] Figure 1 is a structural diagram of a power control circuit provided by an embodiment of the present invention;

[0018] Figure 2 is a structural block diagram of a power control circuit provided by an embodiment of the present invention;

[0019] Figure 3 It is the structural diagram of another power control circuit provided by the embodiment of the present utility model;

[0020] Figure 4 It is the structural diagram of yet another power control circuit provided by the embodiment of the present utility model;

[0021] Figure 5 It is the structural diagram of still another power control circuit provided by the embodiment of the present utility model;

[0022] Figure 6 It is the structural diagram of the fifth power control circuit provided by the embodiment of the present utility model;

[0023] Figure 7 It is the structural diagram of the sixth power control circuit provided by the embodiment of the present utility model. Specific embodiments

[0024] The present utility model will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present utility model, but do not limit the present utility model in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several modifications and improvements can still be made. These all fall within the protection scope of the present utility model.

[0025] To facilitate the understanding of this application, the following provides a more detailed description of this application in conjunction with the accompanying drawings and specific embodiments. Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not used to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0026] It should be noted that if there is no conflict, the various features in the embodiments of the present utility model can be combined with each other, and all are within the protection scope of this application. In addition, although the functional modules are divided in the device schematic diagram, in some cases, it can be different from the module division in the device. In addition, the terms "first", "second", etc. used herein do not limit the data and execution order, but only distinguish the same items or similar items with basically the same functions and roles.

[0027] To solve the cost problem of the power control method for adjusting the heating device by using multiple different heating elements, the embodiment of the present utility model provides a power control circuit. Please refer to Figure 1, the power control circuit includes devices such as an inductor L1, a capacitor C1, and a switching transistor Q1. In this circuit, a pulse width modulation signal can be used to control the conduction or cutoff of a group of switching transistors Q1 to control the heating resistor RT to continuously adjust the heating power. In Figure 1 In the shown circuit, the inductor L1 and the capacitor C1 form a traditional LC filter circuit. Although it can absorb the voltage spike generated when the switching transistor Q1 turns off, since the resistance value of the heating resistor RT is usually small, high-frequency oscillations will occur in the inductor L1 and the capacitor C1 when the switching transistor Q1 is conducting. When the capacitor C1 charges and discharges, a large spike current Ipk = C0 * dV / dt will be generated in the bus input, where C0 is the capacitance value of the capacitor C1 and V is the voltage across the capacitor C1. When this circuit is applied to a water heating device with a rated power of 5.5 kW and a working voltage of 350 V, at the moment when the switching transistor Q1 turns on, the current spike reaches 21.2 A. After the circuit stabilizes, the current amplitude is 11.3 A, and the difference between the two reaches 9.9 A. The current spike reaches 87% of the platform current, that is, the current spike is close to twice the normal working current.

[0028] The large spike current may damage the switching transistor and cause electromagnetic interference problems. In new energy devices, such as new energy vehicles, a large current spike is also likely to trigger over-power protection of the battery management system or the on-board charger in an electric vehicle during the device charging process. That is, in such a circuit, in order to improve safety, the device requires an on-board charger and switching transistors with a larger power specification, resulting in increased costs.

[0029] To solve the above technical problems, an embodiment of the present invention further provides another power control circuit and a heating device. In this circuit, the power can be continuously adjusted and the number of switching transistors used is small, which can reduce the cost of power control. Moreover, in the process of power adjustment, the spike current in the circuit is suppressed by an inductive element and a current limiting module, and at the same time, the spike voltage in the circuit can be suppressed by a capacitive module, improving the safety of the circuit.

[0030] In the first aspect, an embodiment of the present invention provides a power control circuit. This power control circuit is applied to a heating device, and the heating device includes a heating module 210 for generating heat. Refer to Figure 2 , the power control circuit includes an inductive module 110, a capacitive module 120, a current limiting module 130, a first switching module 140, and a control module 150.

[0031] The first end of the inductive module 110 is used to connect to the first end of the input power supply 300. The second end of the inductive module 110 is respectively connected to the first end of the current-limiting module 130 and the first end of the heating module 210. The second end of the current-limiting module 130 is connected to the first end of the capacitive module 120. The second end of the heating module 210 is connected to the first end of the first switching module 140. The second end of the first switching module 140 is respectively connected to the second end of the capacitive module 120 and the second end of the input power supply 300. The driving end of the first switching module 140 is connected to the first end of the control module 150.

[0032] Among them, the control module 150 is used to output a first pulse width modulation signal to the first switching module 140. The first switching module 140 is used to alternately conduct and turn off according to the first pulse width modulation signal to control the heating power of the heating module 210. The inductive module 110 is used to suppress the spike current generated by the power control circuit when the first switching module 140 is conducting. The capacitive module 120 is used to absorb the spike voltage generated by the power control circuit when the first switching module 140 is turned off. The current-limiting module 130 is used to limit the charging and discharging current of the capacitive module 120.

[0033] Please refer to Figure 3 , the heating module 210 may include devices such as a resistor RT that can be used to generate heat. The resistor RT can be a positive temperature coefficient thermistor, whose resistance value increases significantly with the increase in temperature, or it can be a metal ceramic heating tube, a thick film resistor or a thin film resistor. In a water heating device, the resistor RT can be used to heat water. The inductive module 110 may include devices such as an inductor L1 that can generate a back electromotive force; the capacitive module 120 may include devices such as a capacitor C1 that can store energy. The current-limiting module 130 may include devices such as a resistor R1 that can limit the magnitude of the current. The number and type of resistors in the heating module 210 and the current-limiting module 130, the inductor in the inductive module 110, and the capacitor in the capacitive module 120 can be set according to actual needs and are not limited here.

[0034] The control module 150 can adopt a microcontroller unit (MCU) or a digital signal processing (DSP) controller, etc.

[0035] The input power supply 300 can be a DC power supply, and its voltage amplitude can be set according to actual needs. The first end of the input power supply 300 can be the positive pole of the power supply, and the second end can be the negative pole of the power supply.

[0036] The first Pulse Width Modulation (PWM) signal is a periodic square wave signal, and its pulse width changes with the modulation signal. By changing the duty cycle of the first PWM signal (i.e., the ratio of the pulse width to the period), the conduction or cutoff of the loop among the input power supply 300, the inductive module 110, the heating module 210, and the first switch module 140 can be controlled. Thus, the working time of the heating module 210 can be effectively controlled to control the average power in the circuit, thereby achieving the power control of the heating module 210 in the circuit. That is to say, in the power control circuit provided by the present utility model, the magnitude of the heating power is continuously controlled by adjusting the duty cycle of the first PWM signal. Compared with controlling the heating power by using multiple heating elements with different powers, the present utility model can use the same set of switch modules to achieve different powers, reduce the number of switching tubes used, and thus reduce the cost of the power control circuit.

[0037] In addition, in this power control circuit, when the first switch module 140 is conducting, the inductive module 110, the heating module 210, the first switch module 140, the current limiting module 130, and the capacitive module 120 form a conducting loop, and the inductive module 110 and the current limiting module 130 can suppress the spike current on the DC bus; when the first switch module 140 is off, the inductive module 110, the heating module 210, the first switch module 140, the current limiting module 130, and the capacitive module 120 form an absorption loop, the capacitive module 120 can absorb the spike voltage, and the current limiting module 130 can limit the charging and discharging current of the capacitive module 120. That is to say, in the power control circuit provided by the present utility model, during the power adjustment process, the spike current in the circuit is suppressed by the inductive element and the current limiting module 130, and at the same time, the capacitive module 120 can suppress the spike voltage in the circuit, improving the safety of the circuit.

[0038] In some of the embodiments, please refer to Figure 3 , the first switch module 140 includes a first switching tube Q1 and a first driving unit 141. The first end of the first switching tube Q1 is connected to the first end of the heating module 210, the second end of the first switching tube Q1 is connected to the second end of the capacitive module 120, the third end of the first switching tube Q1 is connected to the first end of the first driving unit 141, and the second end of the first driving unit 141 is connected to the first end of the control module 150.

[0039] Specifically, the first switching transistor Q1 can be an N-type IGBT transistor. The first end of the first switching transistor Q1 is the collector of the IGBT transistor, the second end is the emitter, and the third end is the gate. The first driving unit 141 includes a resistor R2 and a resistor R3. Among them, the first end of the control module 150 is connected to the first end of the resistor R2. The second end of the resistor R2 is respectively connected to the first end of the resistor R3 and the first end of the first switching transistor Q1. The second end of the resistor R3 is connected to the second end of the first switching transistor Q1.

[0040] In this first switching module 140, the resistor R2 and the resistor R3 in the first driving unit 141 can provide appropriate voltage and current based on the first PWM signal to control the conduction and cut-off of the first switching transistor Q1, which helps to ensure the stability and reliability of the switching, and can avoid damage to the first switching transistor Q1 due to excessive voltage pulses.

[0041] In some of the embodiments, refer to Figure 3 , the power control circuit further includes a voltage acquisition module 160. The voltage acquisition module 160 is respectively connected to the input power supply 300 and the second end of the control module 150. The voltage acquisition module 160 is used to divide the voltage of the input power supply 300 and output a divided voltage signal to the control module 150.

[0042] In this embodiment, the control module 150 can monitor the input voltage through the voltage acquisition module 160, can be used to adjust the duty cycle of the PWM signal to adjust the required power, and can achieve overvoltage or undervoltage protection based on the monitored input voltage, improving the safety of the circuit.

[0043] In some of the embodiments, refer to Figure 3 , the voltage acquisition module 160 includes a resistor R5 and a resistor R6. The first end of the resistor R5 is respectively connected to the first end of the input power supply 300 and the first end of the inductive module 110. The second end of the resistor R5 is respectively connected to the second end of the control module 150 and the first end of the resistor R6. The second end of the resistor R6 is connected to the second end of the input power supply 300.

[0044] Specifically, the first end of the resistor R5 is respectively connected to the first end of the input power supply 300 and the first end of the inductor L1. In this circuit, the resistor R5 and the resistor R6 divide the voltage of the input power supply 300 and transmit the divided voltage signal to the control module 150. The control module 150 can determine the magnitude of the input voltage based on this signal. In this embodiment, through the divided voltage signal of the resistor R5 and R6, the control module 150 can determine the magnitude of the input voltage.

[0045] In some of the embodiments, refer to Figure 3, the power control circuit further includes a sampling resistor R4. The first end of the sampling resistor R4 is respectively connected to the second end of the first switch module 140 and the third end of the control module 150, and the second end of the sampling resistor R4 is respectively connected to the fourth end of the control module 150, the second end of the capacitive module 120, and the second end of the input power supply 300.

[0046] In this circuit, the control module 150 can calculate the voltage difference across the sampling resistor R4 to obtain the magnitude of the current flowing through the first switch module 140. For the specific calculation method, reference can be made to the prior art and will not be limited here. After obtaining the current, the control module 150 can subsequently adjust the duty cycle of the PWM signal based on the current to adjust the required power, and can implement overcurrent or undercurrent protection based on the monitored current to improve the safety of the circuit.

[0047] In some embodiments, refer to Figure 4 and Figure 5 , the inductor L1 is a common-mode inductor. The first end of the common-mode inductor is used to connect the first end HV+ of the input power supply 300, the second end of the common-mode inductor is respectively connected to the first end of the current-limiting module 130 and the first end of the heating module 210, the third end of the common-mode inductor is used to connect the second end HV- of the input power supply 300, and the fourth end of the common-mode inductor is connected to the second end of the capacitive module 120.

[0048] Specifically, the second end of the common-mode inductor is respectively connected to the first end of the resistor R1 and the first end of the resistor RT, and the fourth end of the common-mode inductor is connected to the second end of the capacitor C1. In this embodiment, the use of a common-mode inductor can effectively suppress electromagnetic interference from the power supply so that it will not spread to the load part, thus ensuring the stable operation of the load part. And by using a common-mode inductor, the noise caused by interference in the power supply can be reduced, thereby improving the stability and reliability of the entire system.

[0049] In some embodiments, refer to Figure 6 , the power control circuit further includes a diode D1. The anode of the diode D1 is respectively connected to the second end of the inductive module 110, the first end of the current-limiting module 130, and the first end of the heating module 210, and the cathode of the diode D1 is respectively connected to the second end of the current-limiting module 130 and the first end of the capacitive module 120.

[0050] Specifically, the anode of diode D1 is respectively connected to the second end of inductor L1, the first end of resistor RT, and the first end of resistor R1, and the cathode of diode D1 is respectively connected to the second end of resistor R1 and the first end of capacitor C1. In this power control circuit, when the first switching transistor Q1 is turned on and then off, diode D1 is turned on to short-circuit resistor R1, and capacitor C1 can quickly absorb the spike voltage generated by inductor L1 and the first switching transistor Q1 during the turn-off process of the first switching transistor Q1, preventing the spike voltage from breaking down the first switching transistor Q1 and improving the reliability and safety of the circuit operation.

[0051] In some of these embodiments, referring to Figure 5 and Figure 7 , the power control circuit further includes a second switching module 170. The first end of the second switching module 170 is respectively connected to the second end of the inductive module 110 and the first end of the current limiting module 130, the second end of the second switching module 170 is connected to the first end of the heating module 210, and the driving end of the second switching module 170 is connected to the fifth end of the control module 150. Among them, the control module 150 is further configured to output a second pulse width modulation signal to the second switching module 170 to alternately turn on or off the second switching module 170.

[0052] In this embodiment, the first switching module 140 and the second switching module 170 can jointly control the working time of the heating module 210, thereby adjusting the power.

[0053] Specifically, in some of these embodiments, referring to Figure 5 and Figure 7 , the second switching module 170 includes a second switching transistor Q2 and a second driving unit 171. The first end of the second switching transistor Q2 is respectively connected to the second end of the inductive module 110 and the first end of the current limiting module 130, the second end of the second switching transistor Q2 is connected to the first end of the heating module 210, the third end of the second switching module 170 is connected to the first end of the second driving unit 171, and the second end of the second driving unit 171 is connected to the fifth end of the control module 150.

[0054] Specifically, the second switching transistor Q2 can be an N-type IGBT transistor. The first end of the second switching transistor Q2 is the collector of the IGBT transistor, the second end is the emitter, and the third end is the gate. The second driving unit 171 includes resistor R7 and resistor R8. Among them, the fifth end of the control module 150 is connected to the first end of resistor R7, the second end of resistor R7 is respectively connected to the first end of resistor R8 and the first end of the second switching transistor Q2, and the second end of resistor R8 is connected to the second end of the second switching transistor Q2.

[0055] In the second switch module 170, the resistors R7 and R8 in the second driving unit 171 can provide appropriate voltage and current based on the second PWM signal to control the conduction and cut-off of the second switching transistor Q2, which helps to ensure the stability and reliability of the switch and can avoid damage to the second switching transistor Q2 due to excessive voltage pulses.

[0056] The following describes in detail the specific working process of the power control circuit provided by the embodiments of the present invention in combination with Figure 6 the embodiments shown.

[0057] In this power control circuit, by changing the duty cycle D of the first PWM signal, the working time of the heating module 210 can be controlled to control the average power P of the heating module 210. Among them, the average power P and the duty cycle D satisfy the following relationship:

[0058] P = Vin*(R5 + R6) / R6*(Is / R4)*D;

[0059] Wherein, Vin is the magnitude of the divided voltage signal output by the voltage acquisition module 160, R5 is the resistance value of the resistor R5, R6 is the resistance value of the resistor R6, R4 is the resistance value of the sampling resistor R4, and Is is the magnitude of the current when the first switching transistor Q1 is conducting. That is to say, in the power control circuit provided by the present invention, the duty cycle of the first PWM signal can be adjusted by obtaining the magnitude of the divided voltage signal and the magnitude of the current to continuously control the magnitude of the heating power. And compared with using multiple heating elements with different powers to control the heating power, the present invention uses the same set of switch modules to achieve different powers, reducing the number of switching transistors used, thereby reducing the cost of the power control circuit.

[0060] In addition, in this power control circuit, when the first switching transistor Q1 is conducting, the inductor L1, the resistor RT, the first switching transistor Q1, the resistor R1, and the capacitor C1 form a conducting loop. The inductor L1 can limit the degree of current change, and the charging and discharging current of the capacitor C1 can be limited through the resistor R1, and the oscillation generated by the inductor L1 and the capacitor C1 can be suppressed. When the first switching transistor Q1 is turned off, the diode D1 conducts to short-circuit the resistor R1, and the capacitor C1 can quickly absorb the spike voltage generated by the inductor L1 and the first switching transistor Q1, improving the safety of the circuit. After applying the power control circuit provided by the embodiments of the present invention to a water heating device with a rated power of 5.5 kW and a working voltage of 350 V, at the moment when the first switching transistor Q1 is turned on, the current spike reaches 18.3 A. After the circuit is stable, the current amplitude is 14.4 A. That is to say, the current spike is only 27% of the platform current. Compared with Figure 1 the traditional PWM control method shown, where the current spike is close to 2 times the normal working current when adjusting the power, this embodiment can effectively reduce the peak value of the spike current and improve the safety of the circuit.

[0061] In a second aspect, an embodiment of the present utility model further provides a heating device, which includes a heating module for generating heat and a power control circuit as described in any one of the first aspects. The power control circuit is connected to the heating module.

[0062] In this embodiment, the power control circuit has the same structure and function as the power control circuit described in any one of the first aspects, and will not be described in detail here. In this heating device, the power control circuit can control the heating power of the heating module.

[0063] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model and are not intended to limit them; under the idea of the present utility model, the technical features in the above embodiments or different embodiments can also be combined, and the steps can be implemented in any order, and there are many other changes in different aspects of the present utility model as described above. For the sake of brevity, they are not provided in detail; although the present utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or equivalently replace some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present utility model.

Claims

1. A power control circuit, characterized in that, Applied to a heating device, the heating device includes a heating module for generating heat, and the power control circuit includes an inductive module, a capacitive module, a current limiting module, a first switch module, and a control module; The first end of the inductive module is used to connect to the first end of the input power supply. The second end of the inductive module is respectively connected to the first end of the current limiting module and the first end of the heating module. The second end of the current limiting module is connected to the first end of the capacitive module. The second end of the heating module is connected to the first end of the first switch module. The second end of the first switch module is respectively connected to the second end of the capacitive module and the second end of the input power supply. The driving end of the first switch module is connected to the first end of the control module; Wherein, the control module is used to output a first pulse width modulation signal to the first switch module; The first switch module is used to alternately conduct and turn off according to the first pulse width modulation signal to control the heating power of the heating module; The inductive module is used to suppress the peak current generated by the power control circuit when the first switch module conducts; The capacitive module is used to absorb the peak voltage generated by the power control circuit when the first switch module disconnects; The current limiting module is used to limit the charging and discharging current of the capacitive module.

2. The power control circuit according to claim 1, wherein The power control circuit further includes a voltage acquisition module; The voltage acquisition module is respectively connected to the input power supply and the second end of the control module; The voltage acquisition module is used to divide the voltage of the input power supply and output a divided voltage signal to the control module.

3. The power control circuit according to claim 2, wherein The voltage acquisition module includes resistor R5 and resistor R6; The first end of resistor R5 is respectively connected to the first end of the input power supply and the first end of the inductive module. The second end of resistor R5 is respectively connected to the second end of the control module and the first end of resistor R6. The second end of resistor R6 is connected to the second end of the input power supply.

4. The power control circuit according to claim 2, wherein The power control circuit further includes a sampling resistor; The first end of the sampling resistor is respectively connected to the second end of the first switch module and the third end of the control module. The second end of the sampling resistor is respectively connected to the fourth end of the control module, the second end of the capacitive module, and the second end of the input power supply.

5. The power control circuit according to claim 4, wherein The inductive module includes a common mode inductor; The first end of the common mode inductor is used to connect to the first end of the input power supply. The second end of the common mode inductor is respectively connected to the first end of the current limiting module and the first end of the heating module. The third end of the common mode inductor is used to connect to the second end of the input power supply. The fourth end of the common mode inductor is connected to the second end of the capacitive module.

6. The power control circuit according to any one of claims 1-5, characterized in that, The power control circuit further includes a diode; The anode of the diode is respectively connected to the second end of the inductive module, the first end of the current limiting module, and the first end of the heating module. The cathode of the diode is respectively connected to the second end of the current limiting module and the first end of the capacitive module.

7. The power control circuit according to any one of claims 1-5, characterized in that, The power control circuit further includes a second switch module; The first end of the second switching module is respectively connected to the second end of the inductive module and the first end of the current limiting module, the second end of the second switching module is connected to the first end of the heating module, and the driving end of the second switching module is connected to the fifth end of the control module; Wherein, the control module is further configured to output a second pulse width modulation signal to the second switching module to alternately turn on or off the second switching module.

8. The power control circuit according to claim 7, wherein The first switching module includes a first switching tube and a first driving unit; The first end of the first switching tube is connected to the first end of the heating module, the second end of the first switching tube is connected to the second end of the capacitive module, the third end of the first switching tube is connected to the first end of the first driving unit, and the second end of the first driving unit is connected to the first end of the control module.

9. The power control circuit according to claim 8, wherein The second switching module includes a second switching tube and a second driving unit; The first end of the second switching tube is respectively connected to the second end of the inductive module and the first end of the current limiting module, the second end of the second switching tube is connected to the first end of the heating module, the third end of the second switching module is connected to the first end of the second driving unit, and the second end of the second driving unit is connected to the fifth end of the control module.

10. A heating device, characterized in that, It includes a heating module for generating heat and the power control circuit according to any one of claims 1-9; The power control circuit is connected to the heating module.

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