Digital control device of resonance circuit and induction cooker

Abstract

The embodiment of the present application provides a digital control device and an induction cooker of a resonant circuit, which relate to the field of electronic technology. The digital control device of the resonant circuit includes: a digital control module, an inverter module, a resonant module and a DC power supply module; the DC power supply module is connected to the resonant module and is used to supply power to the resonant module; the resonant module is grounded through the inverter module; the digital control module is connected to the inverter module and is used to send a control pulse signal to the inverter module, and the control pulse signal is used to control the opening and closing of the inverter module, so that the resonant module generates a resonant current. Through the control of the inverter module by the digital control module, the output power of the device can be more accurately controlled, while avoiding damage to the device due to overload.

Description

Technical Field

[0001] The present application relates to the field of electronic technology, and in particular to a digital control device for a resonant circuit and an induction cooker. Background Art

[0002] At present, the control circuit of the induction cooker generally includes devices such as MCU (Microcontroller Unit), RC filter, oscillator, synchronization circuit, IGBT (Insulated Gate Bipolar Transistor). The MCU outputs a pulse signal, which reaches the oscillator after passing through the RC filter circuit. The oscillator then outputs a pulse signal, and the pulse signal of the oscillator is used to control the operation of the IGBT (Insulated Gate Bipolar Transistor). However, this process may cause the following problems. For example, the pulse signal output by the MCU will be deformed after RC filtering, and the pulse width of the pulse signal is no longer a constant value; the delay of the synchronization signal of the synchronization circuit to the oscillator cannot be adjusted; and the pulse signal controlling the IGBT is limited by the amplitude and frequency of the oscillator.

[0003] It can be seen from this that the output power of the induction cooker in the prior art is difficult to adjust and control. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide a digital control device and an induction cooker for a resonant circuit, so as to achieve a technical effect of more accurately controlling the output power of the equipment while avoiding damage to the equipment due to overload.

[0005] To this end, the present application provides the following technical solutions:

[0006] In a first aspect, an embodiment of the present application provides a digital control device for a resonant circuit, including a digital control module, an inverter module, a resonant module, and a DC power supply module;

[0007] The DC power supply module is connected to the resonance module and is used to supply power to the resonance module;

[0008] The resonance module is grounded through the inverter module;

[0009] The digital control module is connected to the inverter module and is used to send a control pulse signal to the inverter module. The control pulse signal is used to control the on and off of the inverter module so that the resonance module generates a resonance current.

[0010] In the above implementation process, the control pulse signal of the digital control module is used to control the opening and closing of the inverter module, so that the inverter module always operates in a zero voltage state, thereby more accurately controlling the output power of the device and avoiding damage to the device due to overload.

[0011] Furthermore, the digital control module is connected to the DC power supply, and the digital control module is used to:

[0012] Obtaining the voltage of the DC power supply module;

[0013] Determining whether the voltage of the DC power supply module is less than a first voltage setting value;

[0014] If the voltage of the DC power supply module is less than the first voltage setting value, controlling the inverter module to work normally;

[0015] If the voltage of the DC power supply module is not less than the first voltage setting value, the inverter module is stopped and the pulse width of the control pulse signal is reduced. When the voltage of the DC power supply module is less than the first voltage setting value, the inverter module is started and the pulse width of the control pulse signal is restored to a preset value.

[0016] In the above implementation process, since the DC power supply module may have surge voltage, and the inverter module will be damaged when the voltage is too high, it needs to be protected. When the voltage of the DC power supply module reaches the preset value, the inverter module stops working and the inverter module is disconnected, thereby protecting the inverter module. At the same time, the digital control module reduces the pulse width of the control pulse signal, which can make the inverter module less impacted when it is turned on next time, thereby better protecting the inverter module; then, the pulse width of the control pulse signal is restored to the preset value, so that the inverter module works normally.

[0017] Furthermore, the digital control module includes a circuit detection unit, which is connected to the inverter module and the resonance module respectively, and is used for:

[0018] Sending a detection pulse signal to the inverter module, wherein the pulse width of the detection pulse signal is determined according to the voltage of the DC power supply module;

[0019] Receiving the detection pulse signal transmitted back through the resonance module;

[0020] Whether the inverter module and the resonance module can work normally is determined according to the returned detection pulse signal.

[0021] In the above implementation process, before the device starts working, it is also necessary to check whether the device has faults and whether it can work normally, so the device needs to be tested. The digital control module may include a circuit detection unit, which sends a detection pulse signal to the inverter module. The detection pulse signal passes through the inverter module and then is transmitted to the resonance module and finally transmitted back to the circuit detection unit. According to the returned detection pulse signal, it is judged whether the inverter module and the cointegration module can work normally. At the same time, the pulse width of the detection pulse signal is determined according to the voltage of the DC power supply module to further ensure the accuracy of the detection result.

[0022] Furthermore, the calculation formula of the pulse width of the detection pulse signal is: PulseWidth=PulseWidthNormal+(V real -V std )·G, wherein PulseWidth is the pulse width of the detection pulse signal, PulseWidthNormal is the standard pulse width of the detection pulse signal, V real is the voltage of the DC power supply module, V std is the standard voltage of the DC power supply module, and G is the set parameter.

[0023] In the above implementation process, since the voltage of the DC power module fluctuates, it cannot be guaranteed that the voltage of the DC power module remains consistent each time the circuit detection unit detects; and the voltage fluctuation of the DC power module may affect the accuracy of the detection result. Therefore, determining the pulse width of the detection pulse signal according to the voltage of the DC power module can effectively improve the accuracy of the detection result. According to the results of multiple tests, the formula of the pulse width of the detection pulse signal and the voltage of the DC power module is obtained; determining the pulse width of the detection pulse signal according to the formula can effectively improve the accuracy of the detection result.

[0024] Furthermore, the device further comprises a time-limited protection module, which is connected to the digital control module and the inverter module respectively, and is used for:

[0025] Obtaining the start time of the inverter module;

[0026] Determining whether the on-time of the inverter module is greater than a first set time;

[0027] If the on time of the inverter module is greater than the first set time, the inverter module is stopped, and after the second set time, the inverter module is started;

[0028] If the on-time of the inverter module is not greater than the first set time, the inverter module is controlled to work normally.

[0029] In the above implementation process, the inverter module may have an opening time exceeding the maximum opening time in actual operation, resulting in overload and damage to the inverter module. Therefore, a time-limited protection module is added between the digital control module and the inverter module to limit the opening time of the inverter module to prevent the opening time of the inverter module from exceeding the maximum opening time, thereby protecting the inverter module.

[0030] Furthermore, the time-limited protection module includes a first voltage comparator, an AND gate circuit, a first battery and a capacitor, the inverting input of the first voltage comparator is connected to the digital control module, the inverting input of the first voltage comparator is grounded after passing through the capacitor, and the non-inverting input of the first voltage comparator is grounded through the first battery; the input of the AND gate circuit is respectively connected to the output of the first voltage comparator and the digital control module, and the output of the AND gate circuit is connected to the inverter module.

[0031] In the above implementation process, the first set time is determined by the first battery and the capacitor: when the control pulse signal is at a high level, the first voltage comparator outputs a high level, the AND gate circuit outputs a high level, the inverter module is turned on, and the capacitor of the time-limited protection module is charged at the same time; after the first set time, the voltage on the capacitor is greater than the first battery voltage, the first voltage comparator outputs a low level, the AND gate circuit outputs a low level, and the inverter module is turned off. It can be seen that the first set time is the time for the capacitor to charge from zero voltage to the first battery voltage; after the inverter module is turned on, the first set time is reached, regardless of whether the control pulse signal is high or low, the output of the AND gate circuit is low, and the inverter module is controlled to be turned off, thereby avoiding damage to the inverter module due to too long an opening time.

[0032] Furthermore, the device further comprises a zero voltage failure detection module, which is connected to the digital control module and the inverter module, and is used for:

[0033] Obtaining the voltage of the inverter module;

[0034] When the voltage of the inverter module is greater than a second voltage setting value, a zero voltage state failure signal is sent to the digital control module.

[0035] In the above implementation process, when the pulse width of the control pulse signal is small, it may cause the inverter module to deviate from the zero voltage state when working, that is, the voltage of the inverter module increases when working, and the excessively high voltage will shorten the life of the inverter module. Therefore, a zero voltage failure detection module is set to detect whether the inverter module is in a zero voltage state, and send the detection result to the digital control module so that the digital control module adjusts the pulse width of the control pulse signal to make the inverter module work in a zero voltage state.

[0036] Further, the digital control module includes a zero voltage adjustment unit, the zero voltage adjustment unit is connected to the zero voltage failure detection module, and the zero voltage adjustment unit is used to:

[0037] Receiving the zero voltage state failure signal;

[0038] The pulse width of the control pulse signal is adjusted so that the inverter module operates in a zero voltage state, and the pulse width of the control pulse signal at this time is set to a minimum value.

[0039] In the above implementation process, after receiving the zero voltage state failure signal, the zero voltage adjustment unit adjusts the pulse width of the control pulse signal to make the inverter module work in the zero voltage state, thereby avoiding damage to the inverter module due to excessive voltage during operation.

[0040] Furthermore, the zero voltage failure detection module includes a second voltage comparator, a NAND gate circuit, a second battery and a resistor, the inverting input end of the second voltage comparator is connected to the inverter module, the inverting input end of the second voltage comparator is grounded after passing through the resistor, and the non-phase input end of the second voltage comparator is grounded through the second battery; the input end of the NAND gate circuit is respectively connected to the output end of the second voltage comparator and the digital control module, and the output end of the NAND gate circuit is connected to the digital control module.

[0041] In the above implementation process, the digital control module sends a high level signal to the input end of the NAND gate circuit. When the voltage of the resistor is lower than the voltage of the second battery, the second voltage comparator outputs a high level and the NAND gate circuit outputs a low level, indicating that the inverter module is working in a zero voltage state; when the voltage of the resistor is higher than the voltage of the second battery, the second voltage comparator outputs a low level and the NAND gate circuit outputs a high level, indicating that the inverter module is not working in a zero voltage state.

[0042] In a second aspect, an embodiment of the present application provides an induction cooker, comprising a digital control device for the resonant circuit of the first aspect.

[0043] In the above-mentioned implementation process, the digital control device of the resonant circuit of the embodiment of the present application controls the opening and closing of the inverter module through the control pulse signal of the digital control module, so that the inverter module always operates in a zero voltage state, thereby more accurately controlling the output power of the equipment and avoiding damage to the equipment due to overload; on this basis, a time-limited protection module and a zero-voltage failure detection module are added to better protect the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 A schematic structural diagram of a digital control device for a resonant circuit provided in Embodiment 1 of the present application;

[0046] Figure 2 A circuit diagram of a digital control device for a resonant circuit provided in Embodiment 1 of the present application;

[0047] Figure 3 A schematic structural diagram of a digital control device for a resonant circuit provided in Embodiment 2 of the present application;

[0048] Figure 4 A schematic structural diagram of a digital control module provided in Embodiment 2 of the present application;

[0049] Figure 5a A circuit diagram of a time-limited protection module provided in Embodiment 2 of the present application;

[0050] Figure 5b A circuit diagram of a time-limited protection module provided in Embodiment 2 of the present application;

[0051] Figure 6a A circuit diagram of a zero voltage failure detection module provided in Embodiment 2 of the present application;

[0052] Figure 6b A circuit diagram of a zero voltage failure detection module provided in Embodiment 2 of the present application.

[0053] Icons: 110-digital control module; 120-DC power supply module; 130-resonance module; 140-inversion module; 210-digital control module; 220-DC power supply module; 230-resonance module; 240-inversion module; 250-zero voltage failure detection module; 260-time-limited protection module; 310-pulse sending unit; 320-circuit detection unit; 330-zero voltage adjustment unit. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0055] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0056] Embodiment 1

[0057] See also Figure 1 , Figure 1 A schematic structural diagram of a digital control device for a resonant circuit provided in Embodiment 1 of the present application.

[0058] A digital control device for a resonant circuit in the first embodiment of the present application can be applied to the control circuit of an induction cooker. By controlling the inverter module through the digital control module, the output power of the device can be more accurately controlled, while avoiding damage to the device due to overload.

[0059] The above-mentioned device includes: a digital control module 110, a DC power supply module 120, a resonance module 130 and an inverter module 140, wherein: the DC power supply module 120 is connected to the resonance module 130, the resonance module 130 is connected to the inverter module 140, the inverter module 140 is grounded, and the DC power supply module 120, the resonance module 130 and the inverter module 140 form a closed loop; the digital control module 110 is connected to the inverter module 140, the digital control module sends a control pulse signal to the inverter module 140, and the control pulse signal controls the opening and closing of the inverter module 140.

[0060] Exemplarily, the functions of the above modules are: the DC power module 120 supplies power to the resonance module 130; when the inverter module 140 is turned on, the DC power module 120, the resonance module 130, and the inverter module 140 form a closed loop, and the DC power module 120 charges the resonance module 130; when the inverter module 140 is turned off, the closed loop formed by the DC power module 120, the resonance module 130, and the inverter module 140 is disconnected, and the DC power module 120 no longer supplies power to the resonance module 130, and the resonance module 130 generates a resonance current. The inverter module is continuously turned on and off to drive the device to work.

[0061] Optionally, in order to prevent the above-mentioned device from being damaged by surge voltage, the working voltage of the above-mentioned device can be limited, and when the voltage is too high, the operation of the above-mentioned device is stopped. The embodiment of the present application provides an implementation method as follows: the digital control module 110 is connected to the DC power module 120, and the digital control module 110 obtains the voltage of the DC power module 120. When the voltage of the DC power module 120 reaches the maximum allowable value, in order to avoid the device being damaged by the large voltage, the digital control module 110 stops the operation of the inverter module 140, and at the same time reduces the pulse width of the control pulse signal, the inverter module 140 is disconnected, and the entire device stops working, thereby protecting the entire device; thereafter, when it is detected that the voltage of the DC power module 120 drops below the maximum allowable value, the inverter module 140 is started. Since the pulse width of the control pulse signal has been reduced, the impact on the inverter module 140 when it is turned on is relatively small, thereby better protecting the inverter module 140; thereafter, the pulse width of the control pulse signal is restored to the preset value to ensure the normal operation of the device.

[0062] See also Figure 2 , Figure 2 A circuit diagram of a digital control device for a resonant circuit provided in Embodiment 1 of the present application.

[0063] A circuit diagram of a control device for a resonant circuit according to a first embodiment of the present application includes:

[0064] The digital control module 110 includes an MCU (Microcontroller Unit). The MCU is a single-chip microcomputer with programming functions, which can meet various control needs and perform different combination controls for different applications. Exemplarily, the MCU used in the digital control module 110 can be of various models, such as: MCS-51 series, 61 single-chip microcomputer series, AVR series, MSP430 series, all of which can be used as the MCU of the digital control module. Exemplarily, the MCU sends a control pulse signal to the input end of the inverter module, and the control pulse signal controls the opening and closing of the inverter module. Exemplarily, when the control pulse signal is at a high level, the inverter module is turned on; when the control pulse signal is at a low level, the inverter module is turned off.

[0065] The DC power supply module 120 includes a DC power supply DC and a DC side capacitor C2, and the DC power supply DC and the DC side capacitor C2 are connected in parallel. For example, the DC power supply can be a power supply after rectification of the mains, the positive electrode of the DC power supply is connected to the resonance module 230, and the negative electrode is grounded; the DC side capacitor C2 protects the circuit from damage caused by instantaneous large current.

[0066] The resonance module 130 includes a coil L1, a resistor R1 and a resonance capacitor C1. The coil L1 is connected in series with the resistor R1, and the coil L1 and the resistor R1 are connected in parallel with the resonance capacitor C1. When the inverter module 140 is turned on, the DC power module 120, the resonance module 130, and the inverter module 140 form a closed loop. At this time, the DC power supply DC charges the coil L1, and the capacitor C1 is disconnected; when the inverter module 140 is turned off, the closed loop formed by the DC power module 120, the resonance module 130, and the inverter module 140 is disconnected. At this time, the DC power supply DC no longer charges the coil L1, and the coil L1, the resistor R1 and the capacitor C1 form a resonance circuit, and a resonance current is generated in the process of continuous charging and discharging of the coil L1 and the capacitor C1.

[0067] The inverter module 140 includes an IGBT (Insulated Gate Bipolar Transistor) and a diode D1. The drain and source of the IGBT are connected in reverse parallel with the diode D1. The gate of the IGBT is connected to the digital control module 110. Exemplarily, the opening and closing of the IGBT is controlled by the digital control module 210.

[0068] Optionally, the digital control module 110 is also connected to the resonance module 130 to collect the voltage value of the resonance module, and the collection position is one end where the resonance module is connected to the inverter module. When the collected voltage value is zero, the control pulse signal sent by the digital control module is high level, and the IGBT is turned on to ensure that the IGBT works in a zero voltage state.

[0069] The key point of the embodiment of the present application is to use the pulse signal output by the MCU of the digital control module as the control signal to control the opening and closing of the IGBT, so that the IGBT always operates in a zero voltage state, thereby more accurately controlling the output power of the device and avoiding damage to the device due to overload.

[0070] Embodiment 2

[0071] See also Figure 3 , Figure 3 A schematic structural diagram of a digital control device for a resonant circuit provided in Embodiment 2 of the present application.

[0072] In order to better enable the inverter module to operate in a zero voltage state and protect the inverter module, a digital control device for a resonant circuit in the second embodiment of the present application mainly adds two modules compared with the first embodiment: a zero voltage failure detection module 250 and a time-limited protection module 260, wherein the zero voltage failure detection module 250 is used to better enable the inverter module 240 to operate in a zero voltage state; the time-limited protection module 260 is used to limit the opening time of the inverter module 240 to avoid overloading of the inverter module 240.

[0073] The device of the second embodiment includes: a digital control module 210, a DC power supply module 220, a resonance module 230, an inverter module 240, a zero voltage failure detection module 250 and a time-limited protection module 260, wherein: the DC power supply module 220 is connected to the resonance module 230, the resonance module 230 is connected to the inverter module 240, the inverter module 240 is grounded, and the DC power supply module 220, the resonance module 230 and the inverter module 240 form a closed loop; the digital control module 210 is connected to the inverter module 240 through the time-limited protection module 260, and the digital control module 210 sends a control pulse signal After passing through the time-limited protection module 260, it is transmitted to the inverter module 240, and the control pulse signal controls the opening and closing of the inverter module 240; the digital control module 210 is connected to the DC power supply module 220 to collect the voltage value of the DC power supply module 220; the digital control module 210 is connected to the resonance module 230; the zero voltage failure detection module 250 is respectively connected to the digital control module 210 and the inverter module 240, and the zero voltage failure detection module 240 collects the voltage value of the inverter module 240, detects whether the voltage value of the inverter module 240 reaches the preset value, and sends the detection result to the digital control module 210.

[0074] The digital control module 210 , the DC power supply module 220 , the resonance module 230 , and the inverter module 240 have the same structure and function as the modules in the first embodiment of the present application, and will not be described in detail here.

[0075] For example, if the pulse width of the control pulse signal is too small, the inverter module may be caused to operate in a non-zero voltage state, thereby damaging the inverter module. To solve the above problem, the embodiment of the present application provides an implementation method: a zero voltage failure detection module 250 is provided, and the zero voltage failure detection module 250 can detect whether the inverter module 240 operates in a zero voltage state. When the inverter module 240 does not operate in a zero voltage state, a zero voltage failure signal is sent to the digital control module 310. The digital control module 210 adjusts the control pulse signal to be sent next according to the zero voltage failure signal so that the inverter module operates in a zero voltage state.

[0076] For example, if the pulse width of the control pulse signal is too large, the inverter module is turned on for too long, and eventually the inverter module is damaged due to overload. To solve the above problem, the embodiment of the present application provides an implementation method: a time-limited protection module 260 is set, and the digital control module 210 is connected to the inverter module 240 through the time-limited protection module 260. The time-limited protection module 260 can monitor the turn-on time of the inverter module in real time. When the turn-on time of the inverter module 340 is greater than the maximum turn-on time, the inverter module 240 is forced to stop, thereby avoiding the inverter module 240 from being damaged due to overload.

[0077] See also Figure 4 , Figure 4 A schematic structural diagram of a digital control module provided in Example 2 of the present application.

[0078] In order to better realize the function of the digital control device of the resonant circuit of the second embodiment of the present application, the digital control module of the second embodiment of the present application specifically includes: a pulse sending unit 310, a circuit detection unit 320 and a zero voltage adjustment unit 330.

[0079] The pulse sending unit 310 is connected to the inverter module 240, or when there is a time-limited protection module 260, the inverter module 240 is connected through the time-limited protection module 260. The pulse sending unit 310 sends a control pulse signal to the inverter module 240. When the signal is at a high level, the inverter module 240 is turned on; when the signal is at a low level, the inverter module 240 is turned off. At the same time, the pulse sending unit 310 can adjust the pulse width of the control pulse signal to meet the requirements for output power, or make the inverter module 240 work in a zero voltage state.

[0080] The circuit detection unit 320 is connected to the inverter module 240 and the resonance module 230 respectively, and the circuit detection unit 320 is used to:

[0081] Sending a detection pulse signal to the inverter module 240, wherein the pulse width of the detection pulse signal is determined according to the voltage of the DC power supply module 220;

[0082] Receive the detection pulse signal transmitted back through the resonance module 230;

[0083] According to the returned detection pulse signal, it is determined whether the inverter module 240 and the resonance module can work normally.

[0084] Exemplarily, before the resonant module 230 and the inverter module 240 start working, they can be tested to detect whether the resonant module 230 and the inverter module 240 can work normally. The embodiment of the present application provides an implementation as follows: the digital control module 210 includes a circuit detection unit 320, and the circuit detection unit 320 is connected to the resonant module 230 and the inverter module 240 respectively. The circuit detection unit 320 sends a detection pulse signal, and the detection pulse signal passes through the inverter module 240 and the resonant module 230, and is finally transmitted back to the circuit detection unit 320. The circuit detection unit 320 determines whether the resonant module 130 and the inverter module 140 can work normally according to the returned detection pulse signal.

[0085] Exemplarily, the voltage of the DC power supply module 220 may affect the detection result of the circuit detection unit 320. In order to solve this problem, the second embodiment of the present application provides a calculation formula, which can effectively improve the accuracy of the detection result. The calculation formula of the pulse width of the detection pulse signal is: PulseWidth=PulseWidthNormal+(V real -V std )·G, where PulseWidth is the pulse width of the detection pulse signal, PulseWidthNormal is the standard pulse width of the detection pulse signal, V real is the voltage of the DC power module, V std is the standard voltage of the DC power module, and G is the setting parameter.

[0086] The zero voltage adjustment unit 330 is connected to the zero voltage failure detection module 250, and the zero voltage adjustment unit 330 is used to:

[0087] receiving a zero voltage state failure signal;

[0088] The pulse width of the control pulse signal is adjusted so that the inverter module 240 operates in a zero voltage state, and the pulse width of the control pulse signal at this time is set to a minimum value.

[0089] Exemplarily, after receiving the zero voltage state failure signal, the zero voltage adjustment unit 330 sends an instruction to the pulse sending unit 310 ; after receiving the instruction, the pulse sending unit 310 adjusts the pulse width of the control pulse signal according to the instruction.

[0090] Exemplarily, the output power of the device is determined by the pulse width of the control pulse signal. The smaller the pulse width, the lower the output power. However, if the pulse width is too small, the inverter module 240 will work in a non-zero voltage state. In order to achieve low output power while making the inverter module 240 work in a zero voltage state, the embodiment of the present application provides an implementation method: setting a minimum pulse width of the control pulse signal, which is determined by the zero voltage adjustment unit 330, and the above minimum value is a pulse width that just makes the inverter module 240 work in a zero voltage state.

[0091] See also Figure 5a , Figure 5a A circuit diagram of a time-limited protection module provided in Example 2 of the present application.

[0092] A circuit of a time-limited protection module provided in Embodiment 2 of the present application includes: a first voltage comparator VC1, an AND gate circuit, a first battery B1 and a capacitor C3, wherein the inverting input terminal of the first voltage comparator VC1 is connected to a digital control module, the inverting input terminal of the first voltage comparator VC1 is grounded after passing through the capacitor C3, and the non-inverting input terminal of the first voltage comparator VC1 is grounded through the first battery B1; the input terminal of the AND gate circuit is respectively connected to the output terminal of the first voltage comparator VC1 and the digital control module, and the output terminal of the AND gate circuit is connected to the inverter module.

[0093] Optionally, see Figure 5b The circuit of the time-limited protection module may also include a resistor R2, a resistor R3 and a diode D2, wherein the resistor R2 is connected in series with the resistor R3, and the resistor R2 is connected in reverse parallel with the diode D2. At this time, the reverse input end of the first voltage comparator VC1 is connected to the digital control module through the resistor R2, the resistor R3 and the diode D2, the resistor R2 and the resistor R3 play a voltage dividing role, the diode D2 prevents current backflow, and the resistor R2, the resistor R3 and the diode D2 play a protective role in the circuit.

[0094] Exemplarily, the first battery B1 and the capacitor C3 jointly determine the maximum turn-on time of the inverter module: when the control pulse signal is at a high level, the first voltage comparator VC1 outputs a high level, the AND gate circuit outputs a high level, the inverter module is turned on, and the capacitor C3 of the time-limited protection module is charged at the same time; after a period of time, the voltage of the capacitor C3 is greater than the voltage of the first battery B1, the first voltage comparator VC1 outputs a low level, the AND gate circuit outputs a low level, and the inverter module is turned off. It can be seen that the above maximum turn-on time is the time for the capacitor C3 to charge from zero voltage to the voltage of the first battery B1; after the turn-on time of the inverter module reaches the maximum turn-on time, regardless of whether the control pulse signal is high or low, the output of the AND gate circuit is low, and the inverter module is controlled to be turned off, thereby avoiding damage to the inverter module due to too long turn-on time.

[0095] See also Figure 6a , Figure 6a A circuit diagram of a zero voltage failure detection module provided in Embodiment 2 of the present application.

[0096] A circuit of a zero voltage failure detection module provided in Example 2 of the present application includes a second voltage comparator VC2, a NAND gate circuit, a second battery B2 and a resistor R4, wherein the inverting input terminal of the second voltage comparator VC2 is connected to the inverter module, the inverting input terminal of the second voltage comparator VC2 is grounded after passing through the resistor R4, and the non-phase input terminal of the second voltage comparator VC2 is grounded through the second battery B2; the input terminal of the NAND gate circuit is respectively connected to the output terminal of the second voltage comparator VC2 and the digital control module, and the output terminal of the NAND gate circuit is connected to the digital control module.

[0097] Exemplarily, the pulse sending unit of the digital control module is connected to the input end of the NAND gate circuit, and the pulse sending unit can also send a failure detection pulse signal to the NAND gate circuit to detect whether the inverter module is in a zero voltage state; the zero voltage adjustment unit is connected to the output end of the NAND gate circuit, and the zero voltage adjustment unit receives the output signal of the NAND gate circuit to determine whether the inverter module is in a zero voltage state.

[0098] Optionally, see Figure 6b The zero voltage failure detection module may further include a resistor R5. The inverter module is connected to the inverting input terminal of the second voltage comparator VC2 via the resistor R5. The inverter module is grounded via the resistors R4 and R5. The resistor R5 acts as a voltage divider and is used to protect the circuit.

[0099] For example, the working mode of the circuit of a zero voltage failure detection module provided in the second embodiment of the present application is as follows: the digital control module sends a high level signal to the input end of the NAND gate circuit. When the voltage of the resistor R4 is lower than the voltage of the second battery B2, the second voltage comparator VC2 outputs a high level, and the NAND gate circuit outputs a low level, indicating that the inverter module is working in a zero voltage state; when the voltage of the resistor R4 is higher than the voltage of the second battery B2, the second voltage comparator VC2 outputs a low level, and the NAND gate circuit outputs a high level, indicating that the inverter module is not working in a zero voltage state.

[0100] To sum up, based on the first embodiment, the second embodiment of the present application solves the problem that the inverter module may be turned on for too long and the inverter module may operate in a non-zero voltage state by adding a time-limited protection module and a zero voltage failure detection module, thereby achieving better technical effects.

[0101] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0102] In addition, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0103] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0104] The above description is only an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0105] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0106] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

Claims

1. A digital control device for a resonant circuit, characterized in that: It includes a digital control module, an inverter module, a resonance module and a DC power supply module; The DC power supply module is connected to the resonance module and is used to supply power to the resonance module; The resonance module is grounded through the inverter module; The digital control module is connected to the inverter module and is used to send a control pulse signal to the inverter module, wherein the control pulse signal is used to control the on and off of the inverter module so that the resonance module generates a resonance current; The digital control module is connected to the DC power supply, and the digital control module is used for: Obtaining the voltage of the DC power supply module; Determining whether the voltage of the DC power supply module is less than a first voltage setting value; If the voltage of the DC power supply module is less than the first voltage setting value, controlling the inverter module to work normally; If the voltage of the DC power module is not less than the first voltage setting value, the inverter module is stopped and the pulse width of the control pulse signal is reduced; when the voltage of the DC power module is less than the first voltage setting value, the inverter module is started and the pulse width of the control pulse signal is restored to a preset value; The digital control module includes a circuit detection unit, which is connected to the inverter module and the resonance module respectively, and is used to: Sending a detection pulse signal to the inverter module, wherein the pulse width of the detection pulse signal is determined according to the voltage of the DC power supply module; Receiving the detection pulse signal transmitted back through the resonance module; According to the returned detection pulse signal, judging whether the inverter module and the resonance module can work normally; The calculation formula of the pulse width of the detection pulse signal is: PulseWidth=PulseWidthNormal+(V real -V std )·G, wherein PulseWidth is the pulse width of the detection pulse signal, PulseWidthNormal is the standard pulse width of the detection pulse signal, V real is the voltage of the DC power supply module, V std is the standard voltage of the DC power supply module, and G is the set parameter.

2. The device according to claim 1, characterized in that It also includes a time-limited protection module, which is connected to the digital control module and the inverter module respectively, and is used to: Obtaining the start time of the inverter module; Determining whether the on-time of the inverter module is greater than a first set time; If the on time of the inverter module is greater than the first set time, the inverter module is stopped, and after the second set time, the inverter module is started; If the on-time of the inverter module is not greater than the first set time, the inverter module is controlled to work normally.

3. The device according to claim 2, characterized in that The time-limited protection module includes a first voltage comparator, an AND gate circuit, a first battery and a capacitor. The inverting input of the first voltage comparator is connected to the digital control module, the inverting input of the first voltage comparator is grounded after passing through the capacitor, and the non-inverting input of the first voltage comparator is grounded through the first battery; the input of the AND gate circuit is respectively connected to the output of the first voltage comparator and the digital control module, and the output of the AND gate circuit is connected to the inverter module.

4. The device according to claim 1, characterized in that It also includes a zero voltage failure detection module, which is connected to the digital control module and the inverter module, and is used to: Obtaining the voltage of the inverter module; When the voltage of the inverter module is greater than a second voltage setting value, a zero voltage state failure signal is sent to the digital control module.

5. The device according to claim 4, characterized in that The digital control module includes a zero voltage adjustment unit, which is connected to the zero voltage failure detection module, and is used to: Receiving the zero voltage state failure signal; The pulse width of the control pulse signal is adjusted so that the inverter module operates in a zero voltage state, and the pulse width of the control pulse signal at this time is set to a minimum value.

6. The device according to claim 4, characterized in that The zero voltage failure detection module includes a second voltage comparator, a NAND gate circuit, a second battery and a resistor. The inverting input end of the second voltage comparator is connected to the inverter module, the inverting input end of the second voltage comparator is grounded after passing through the resistor, and the non-inverting input end of the second voltage comparator is grounded through the second battery; the input end of the NAND gate circuit is respectively connected to the output end of the second voltage comparator and the digital control module, and the output end of the NAND gate circuit is connected to the digital control module.

7. An induction cooker, characterized in that: A digital control device comprising the resonant circuit according to any one of claims 1 to 6.

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