Power mainboard based on intermittent heating technology

Abstract

The utility model relates to the technical field of electromagnetic oven discloses power mainboard based on intermittent heating technology, include: switching power supply, surge protection circuit, IGBT drive circuit, the MCU control circuit of responsible data acquisition, the pot bottom sensor detection circuit of responsible collection pot bottom temperature data, the burning mouth, communication interface, the utility model discloses when low -power operation, electromagnetic oven enters intermittent working mode (high -frequency switch alternative open -close), avoids the equipment overheating problem caused by continuous conduction, can effectively solve the problem of IGBT high temperature, both energy -conserving, reduce invalid power consumption, reduce the whole machine energy consumption, reduce the failure rate caused by high temperature, when appearing instantaneous high pressure, MCU immediately cuts off power output, avoids the surge current impact IGBT and rectifier bridge, plays accurate real -time protection to equipment, through thermistor real -time feedback pot bottom temperature, and MCU dynamic adjustment heating power, avoid the energy waste when empty burning or overheating, improve heating efficiency.

Description

Technical Field

[0001] This utility model relates to the field of induction cooker technology, and more particularly to the field of power motherboards for induction cookers, specifically a power motherboard based on intermittent heating technology. Background Technology

[0002] The power mainboard of an induction cooker is one of its core components, primarily responsible for the high-frequency conversion of electrical energy and controlling the heating process. The power mainboard of an induction cooker mainly includes an IGBT module, drive circuit, control chip, resonant capacitor, protection circuit, and power supply module.

[0003] A search revealed that patent application number CN202222986659.1 discloses an induction cooker control board circuit, including an MCU microprocessor electrically connected to an isolated communication interface module. The isolated communication interface module is used for communication between the CPU microprocessor and the induction cooker's power board. The isolated communication interface module includes a CN1 interface, a CN2 interface, and a CN8 interface. The CN2 interface is electrically connected to an optocoupler circuit, which includes a first optocoupler U3 and a second optocoupler. This circuit, by using optocoupler isolation at the communication port between the MCU microprocessor and the power board, prevents interference between the control board and different power boards, greatly improving the overall stability of the machine.

[0004] Traditional induction cookers use continuous PWM modulation, and the IGBTs are still frequently turned on in the low power range (such as the heat preservation mode), resulting in high heat generation and easy to cause failures and risks due to high temperature. They also lack a fast-response high voltage protection mechanism, which can easily damage the IGBTs or rectifier bridge. Therefore, we need to propose a power motherboard based on intermittent heating technology. Utility Model Content

[0005] The purpose of this invention is to provide a power mainboard based on intermittent heating technology. During low-power operation, the induction cooker enters an intermittent working mode (high-frequency switch alternately opening and closing), avoiding overheating caused by continuous conduction. This effectively solves the problem of high IGBT temperature, saving energy, reducing ineffective power consumption, lowering overall energy consumption, and reducing the failure rate caused by high temperatures. When a sudden high voltage occurs, the MCU immediately cuts off the power output to prevent surge current from impacting the IGBT and rectifier bridge, providing precise real-time protection for the equipment. Through real-time feedback of the pot bottom temperature via a thermistor, the MCU dynamically adjusts the heating power, avoiding energy waste during dry burning or overheating, improving heating efficiency, and thus solving the problems mentioned in the background technology.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a power mainboard based on intermittent heating technology, comprising:

[0007] A switching power supply that converts alternating current to direct current and powers the motherboard;

[0008] A surge protection circuit that shuts down power output when there is a momentary high voltage in the power grid;

[0009] An IGBT drive circuit that receives PWM control signals from the MCU and drives the IGBT module to operate at high frequency.

[0010] The MCU control circuit responsible for data acquisition;

[0011] The bottom-of-the-pot sensor detection circuit is responsible for collecting bottom-of-the-pot temperature data.

[0012] Provides a programming port for programming MCU programs;

[0013] Communication interface used to connect the power mainboard and the control board;

[0014] The switching power supply, MCU control circuit, and IGBT drive circuit are connected in sequence. The programming port, MCU control circuit, and communication interface are connected in sequence. The bottom sensor detection circuit is electrically connected to the MCU control circuit. The surge protection circuit is electrically connected to the MCU control circuit.

[0015] Preferably, the MCU control circuit includes a chip U3. Pin 5 of the chip U3 is connected to a resistor R26 for receiving data, pin 6 of the chip U3 is connected to a resistor R27 for transmitting data, one end of the resistor R26 is connected to a jumper interface J12, one end of the resistor R27 is connected to a jumper interface J13, pin 13 of the chip U3 is connected to a resistor R127 and a diode D9, and pin 18 of the chip U3 is connected to a capacitor EC105, a capacitor C121, and a resistor R125 connected in parallel.

[0016] Preferably, the switching power supply includes a chip U2, a transformer T1, a voltage regulator U5 and a voltage regulator U6 that convert DC voltage to 5V output. Pin 5 of the chip U2 is connected to pin 1 of the transformer T1. Diodes D16 and D17 are connected between pin 4 of the chip U2 and pin 5 of the transformer T1. Diodes D15 and ZD2 are connected between pin 3 of the chip U2 and pin 5 of the transformer T1.

[0017] The voltage regulator U5 has capacitors EC2, C3 and EC5 connected in parallel between pin 1 and pin 2, and capacitors C102, EC31 and EC6 connected in parallel between pin 2 and pin 3.

[0018] A capacitor C3A and a capacitor EC4 are connected in parallel between pin 1 and pin 2 of the voltage regulator U6, and a capacitor EC3 and a capacitor 4 are connected in parallel between pin 2 and pin 3 of the voltage regulator U6.

[0019] A diode D4 is connected to pin 6 of the transformer T1, a resistor R4 is connected to pin 1 of the voltage regulator U5, and a resistor R30 is connected to pin 1 of the voltage regulator U6. The resistors R4 and R30 and the diode D4 are connected together.

[0020] Preferably, the surge protection circuit includes a rectifier bridge DB1. A capacitor C11 is connected between pins 1 and 2 of the rectifier bridge DB1. A diode D1 and a diode D2 are also connected between pins 1 and 2 of the rectifier bridge DB1. The terminals of diodes D1 and D2 are respectively connected to a resistor R9, a capacitor C13 connected in parallel, and a resistor R10. One end of the resistor R9 is connected to a resistor R13, a capacitor EC1, a capacitor C888, and a capacitor C12 connected in parallel. The terminals of C13 and resistor R10 are connected to a resistor R15. One end of the resistor R15 is connected to a capacitor C15, a diode ZD4, and a series resistor R17 and a resistor R20. The resistor R15 is connected to pin 13 of the chip U3, and pin 3 of the rectifier bridge DB1 is connected to pin 17 of the chip U3.

[0021] Preferably, the IGBT driving circuit includes transistors Q7, Q16, and Q103. The emitter of transistor Q7 is connected to the emitter of transistor Q16, the base of transistor Q7 is connected to the base of transistor Q16, the emitter of transistor Q103 is connected to the collector of transistor Q16, and the collector of transistor Q103 is connected to the bases of transistors Q7 and Q16.

[0022] A resistor R105 and a resistor R126 are connected between the base and collector of the transistor Q7. One end of the resistor R105 is connected to a capacitor EC102 and a capacitor C122 connected in parallel. A resistor R112 is connected to the base of the transistor Q103. A resistor R111 is connected between the resistor R112 and the resistor R105. The resistor R112 is connected to pin 7 of the chip U3.

[0023] Preferably, the pot bottom sensor detection circuit includes a connector CN19, with resistors R156 and R22 connected in series on pin 3 of the connector CN19. A resistor R45 and a capacitor C27 are connected in parallel on the connection terminals of resistors R156 and R22. The pot bottom sensor detection circuit also includes a thermistor RT2, with resistor R8 and capacitor C9 connected to its two ends respectively.

[0024] The bottom sensor detection circuit also includes jumper interface J8 connected to pin 10 of chip U3, jumper interfaces J9 and J13 connected in parallel to pin 12 of chip U3, and jumper interfaces J10 and J16 connected in parallel to pin 11 of chip U3.

[0025] Preferably, the programming port includes a connector CN103, pin 2 of the connector CN103 is connected to a 5V power supply, pin 3 of the connector CN103 is connected to pin 3 of the chip U3, and pin 4 of the connector CN103 is connected to pin 4 of the chip U3.

[0026] Preferably, the communication interface includes a connector CN5 and a transistor Q6. Pin 2 of the connector CN5 is connected to the collector of the transistor Q6. A resistor R16 is connected to the base of the transistor Q6. The resistor R16 is connected to a resistor R27. An inductor L2 is connected to pin 3 of the connector CN5. The inductor L2 is connected to a resistor R26. A capacitor C10 is connected between the collector and emitter of the transistor Q6. Pin 2 of the connector CN5 is connected to the collector of the transistor Q6.

[0027] Compared with the prior art, the beneficial effects of this utility model are:

[0028] 1. When the induction cooker is running at low power, it enters an intermittent working mode (the high-frequency switch alternately turns on and off), which avoids the problem of overheating caused by continuous conduction. This can effectively solve the problem of high IGBT temperature, save energy, reduce ineffective power consumption, reduce overall energy consumption, and reduce the failure rate caused by high temperature.

[0029] 2. When a sudden high voltage occurs, the MCU immediately cuts off the power output to prevent the surge current from impacting the IGBT and rectifier bridge, thus providing precise real-time protection for the equipment. The MCU dynamically adjusts the heating power by providing real-time feedback on the bottom temperature of the pot through a thermistor, avoiding energy waste during dry burning or overheating and improving heating efficiency. Attached Figure Description

[0030] Figure 1 This is a system block diagram of the present invention;

[0031] Figure 2 This is the circuit diagram of the switching power supply of this utility model;

[0032] Figure 3 This is a circuit diagram of the surge protection circuit of this utility model;

[0033] Figure 4 This is a circuit diagram of the IGBT drive circuit of this utility model;

[0034] Figure 5 This is a circuit diagram of the MCU control circuit of this utility model;

[0035] Figure 6 This is a circuit diagram of the detection circuit for the bottom sensor of this utility model;

[0036] Figure 7 This is the circuit diagram of the programming port of this utility model;

[0037] Figure 8 This is a circuit diagram of the communication interface of this utility model. Detailed Implementation

[0038] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0039] Please see Figure 1-8 This utility model provides a technical solution: a power mainboard based on intermittent heating technology, comprising:

[0040] A switching power supply that converts alternating current to direct current and powers the motherboard;

[0041] The switching power supply includes a chip U2, a transformer T1, a voltage regulator U5 and a voltage regulator U6 that convert DC voltage to 5V output. Pin 5 of the chip U2 is connected to pin 1 of the transformer T1. Diodes D16 and D17 are connected between pin 4 of the chip U2 and pin 5 of the transformer T1. Diodes D15 and ZD2 are connected between pin 3 of the chip U2 and pin 5 of the transformer T1.

[0042] The voltage regulator U5 has capacitors EC2, C3 and EC5 connected in parallel between pin 1 and pin 2, and capacitors C102, EC31 and EC6 connected in parallel between pin 2 and pin 3.

[0043] A capacitor C3A and a capacitor EC4 are connected in parallel between pin 1 and pin 2 of the voltage regulator U6, and a capacitor EC3 and a capacitor 4 are connected in parallel between pin 2 and pin 3 of the voltage regulator U6.

[0044] A diode D4 is connected to pin 6 of the transformer T1, a resistor R4 is connected to pin 1 of the voltage regulator U5, and a resistor R30 is connected to pin 1 of the voltage regulator U6. The resistors R4 and R30 and the diode D4 are connected together.

[0045] The rectifier diode D3 rectifies the input AC voltage into pulsating DC voltage. Connectors (CN1, CN2) are used for circuit connection. Resistor R3 is the input current limiting resistor to protect subsequent circuit components. Capacitor C8 is the input filter capacitor to smooth the DC voltage and reduce ripple.

[0046] Chip U2 is a switching power supply controller IC that controls the power supply's operating state and timing. Transformer T1 provides electrical isolation and energy transfer. Diode D14 converts the AC output from transformer T1 into DC. Diode D16 improves rectification efficiency, and diode D17 is used for protection or control. Zener diode ZD2 provides voltage reference or overvoltage protection.

[0047] Capacitors (EC2, EC3, EC5) are used for filtering and stabilizing the output voltage. Capacitors (C3A, C3, C4, EC4) further reduce the output ripple. Regulator U5 converts the higher DC voltage into a stable 5V output. Resistor R23 is used to set the output voltage or as a bias resistor.

[0048] A surge protection circuit that shuts down power output when there is a momentary high voltage in the power grid;

[0049] The surge protection circuit includes a rectifier bridge DB1. A capacitor C11 is connected between pins 1 and 2 of the rectifier bridge DB1. A diode D1 and a diode D2 are also connected between pins 1 and 2 of the rectifier bridge DB1. The terminals of diodes D1 and D2 are respectively connected to a resistor R9, a capacitor C13 connected in parallel, and a resistor R10. One end of the resistor R9 is connected to a resistor R13, a capacitor EC1, a capacitor C888, and a capacitor C12 connected in parallel. The terminals of C13 and resistor R10 are connected to a resistor R15. One end of the resistor R15 is connected to a capacitor C15, a diode ZD4, and a series resistor R17 and a resistor R20. The resistor R15 is connected to pin 13 of chip U3. Pin 3 of the rectifier bridge DB1 is connected to pin 17 of chip U3.

[0050] L and N are the input terminals for AC power, namely the live wire and the neutral wire, respectively. Capacitor C11 is used to filter out high-frequency interference signals on the power line. Rectifier bridge DB1 converts AC power to DC power. Diodes D1 and D2 are used as rectifier elements to convert AC power to pulsating DC power.

[0051] Resistor R9 is used for current limiting or voltage division, resistor R10 is used for RC filter network or discharge circuit, capacitor C13 is used for filtering and energy storage, resistor R15 is used for current limiting or voltage division, and resistor R17 is used for precise current limiting or voltage division.

[0052] Capacitor EC1 is used to smooth DC voltage, diode ZD4 provides a stable reference voltage and overvoltage protection, and capacitor C16 is used for filtering or preventing high-frequency interference. The jumper is a jumper connector used to set the circuit's operating mode or configuration parameters.

[0053] An IGBT drive circuit that receives PWM control signals from the MCU and drives the IGBT module to operate at high frequency.

[0054] The IGBT driving circuit includes transistors Q7, Q16, and Q103. The emitter of transistor Q7 is connected to the emitter of transistor Q16, the base of transistor Q7 is connected to the base of transistor Q16, the emitter of transistor Q103 is connected to the collector of transistor Q16, and the collector of transistor Q103 is connected to the bases of transistors Q7 and Q16.

[0055] A resistor R105 and a resistor R126 are connected between the base and collector of the transistor Q7. One end of the resistor R105 is connected to a capacitor EC102 and a capacitor C122 connected in parallel. A resistor R112 is connected to the base of the transistor Q103. A resistor R111 is connected between the resistor R112 and the resistor R105. The resistor R112 is connected to pin 7 of the chip U3.

[0056] Transistor Q7 is used for level shifting and signal inversion, forming part of the Darlington transistor structure. Transistor Q16 works in conjunction with transistor Q7 to form a driver stage, providing sufficient current drive capability. Transistor Q103 is used for signal transmission and power amplification. Diode D15 is used as a freewheeling diode to protect the IGBT from reverse voltage spikes.

[0057] Resistor R105 limits the base current of transistor Q7, resistor R111 is used to set the bias voltage, resistor R112 is used to precisely control the output current, resistor R126 is used for current detection or limiting, and capacitor C122 is used to eliminate high-frequency noise and stabilize the signal.

[0058] The MCU control circuit responsible for data acquisition;

[0059] The MCU control circuit includes a chip U3. Pin 5 of the chip U3 is connected to a resistor R26 for receiving data, and pin 6 of the chip U3 is connected to a resistor R27 for transmitting data. One end of the resistor R26 is connected to a jumper interface J12, and one end of the resistor R27 is connected to a jumper interface J13. Pin 13 of the chip U3 is connected to a resistor R127 and a diode D9. Pin 18 of the chip U3 is connected to a capacitor EC105, a capacitor C121, and a resistor R125 arranged in parallel.

[0060] Resistors (R26, R27) are used as pull-up or pull-down resistors to determine the default level of the pins, enhance signal stability, and prevent signal lines from floating. Resistor R127 is used for voltage division and current limiting. Capacitor C12 is used for filtering, removing high-frequency noise from power supplies or signal lines, making the circuit more stable. Diode D9 is a fast-switching diode, commonly used to protect circuits from reverse voltage surges. For example, in inductive load circuits such as relays, it is used for freewheeling to protect other components from damage by induced electromotive force. Jumper interfaces in the MCU control circuit allow for different connection states by inserting jumper caps or shorting pins, which can be used to configure circuit parameters, select different operating modes, or perform circuit debugging. Capacitor EC105 is an electrolytic capacitor mainly used for power supply filtering, storing and releasing electrical energy, stabilizing power supply voltage, and reducing the impact of power supply ripple on the circuit.

[0061] The bottom-of-the-pot sensor detection circuit is responsible for collecting bottom-of-the-pot temperature data.

[0062] The bottom sensor detection circuit includes a connector CN19, with resistors R156 and R22 connected in series at pin 3 of the connector CN19. Resistors R45 and capacitor C27 are connected in parallel at the connection terminals of resistors R156 and R22. The bottom sensor detection circuit also includes a thermistor RT2, with resistors R8 and capacitor C9 connected at its two ends respectively.

[0063] The bottom sensor detection circuit also includes jumper interface J8 connected to pin 10 of chip U3, jumper interfaces J9 and J13 connected in parallel to pin 12 of chip U3, and jumper interfaces J10 and J16 connected in parallel to pin 11 of chip U3.

[0064] CS is the chip select signal, used to select a specific chip or module for communication; DAT is the data signal line, used to transmit data; CLK is the clock signal line, used to synchronize data transmission; resistors (R8, R13, R16) are pull-up resistors, used to keep the signal lines at a high level until an external device pulls them low.

[0065] Thermistor RT2 is used to detect changes in the temperature of the pot bottom. Its resistance changes with temperature. Resistors R15 and R16 are used to maintain a high level on the signal line. Pin GUOUT is the output signal used to transmit the detection result.

[0066] Provides a programming port for programming MCU programs;

[0067] The programming port includes connector CN103, pin 2 of connector CN103 is connected to a 5V power supply, pin 3 of connector CN103 is connected to pin 3 of chip U3, and pin 4 of connector CN103 is connected to pin 4 of chip U3.

[0068] DSDA and DSCL are I 2 The C-channel communication bus is used as the serial data line (DSDA) and serial clock line (DSCL) for communication between chips. GU01 T and IGBT T1 are signals associated with the IGBT (Insulated Gate Bipolar Transistor). IGBT T1 is the main power switching element, while GU01 T is its drive control signal.

[0069] Communication interface used to connect the power mainboard and the control board;

[0070] The communication interface includes a connector CN5 and a transistor Q6. Pin 2 of the connector CN5 is connected to the collector of the transistor Q6. A resistor R16 is connected to the base of the transistor Q6. The resistor R16 is connected to a resistor R27. An inductor L2 is connected to pin 3 of the connector CN5. The inductor L2 is connected to a resistor R26. A capacitor C10 is connected between the collector and emitter of the transistor Q6. Pin 2 of the connector CN5 is connected to the collector of the transistor Q6.

[0071] Transistor Q6 acts as a switch in the circuit. When there is a suitable electrical signal at its base, transistor Q6 conducts, pulling the RXD signal low; when there is no signal at the base of transistor Q6, transistor Q6 is cut off, and the RXD signal is kept high through the pull-up resistor.

[0072] Resistor R14 serves to limit current and protect the transistor, preventing excessive current from damaging it. Resistor R16 is a pull-up resistor, keeping the RXD signal at a high level when there is no transmission signal.

[0073] Inductors (L1, L2, L3) are used to suppress high-frequency interference and act as filters to ensure the purity of communication signals.

[0074] When there is a high-level signal at the TX terminal, transistor Q6 is turned on, pulling the RXD signal low, thus sending a low-level signal to the external device; when the TX terminal is low, transistor Q6 is turned off, and RXD is pulled up to a high level through R16, thus sending a high-level signal to the external device.

[0075] Signals sent by external devices enter the circuit through the CN5 connector. After passing through a filter circuit composed of inductors L1 and L2 and capacitor C10, further signal processing may be performed.

[0076] The TEST jumper allows you to short-circuit certain test points when needed, facilitating circuit debugging and testing.

[0077] The switching power supply, MCU control circuit, and IGBT drive circuit are connected in sequence. The programming port, MCU control circuit, and communication interface are connected in sequence. The bottom sensor detection circuit is electrically connected to the MCU control circuit. The surge protection circuit is electrically connected to the MCU control circuit.

[0078] When using:

[0079] The switching power supply converts the input 220V AC power to 5V (for the MCU, sensors, etc.) and 15V (for the IGBT driver) to power the entire system. The MCU starts a self-test program, initializes various peripherals (such as ADC and PWM modules), and waits for user input commands.

[0080] The bottom sensor detection circuit monitors the bottom temperature of the pot in real time. If a valid pot (iron and within a reasonable temperature range) is detected, a signal is sent to the MCU to allow entry into heating mode. If no pot is available or the pot is non-compliant, the MCU notifies the control board of an error (e.g., E1) via the communication interface.

[0081] The MCU dynamically adjusts the PWM signal based on the temperature data fed back by the sensor at the bottom of the pot to maintain the stability of the set power. If a voltage fluctuation (such as a surge) is detected in the mains voltage, the MCU quickly cuts off the IGBT drive signal through the surge protection circuit to protect the hardware.

[0082] The surge protection circuit monitors the grid voltage in real time. If a momentary high voltage (such as a lightning strike) is detected, it immediately sends an interrupt signal to the MCU. The MCU triggers the protection logic: shuts down the IGBT drive output → reports a fault code through the communication interface → waits for the grid to recover and then restarts.

[0083] The bottom sensor continuously monitors the temperature of the cookware. If the temperature exceeds the limit (e.g., dry burning), the MCU immediately reduces the frequency or stops heating. The MCU has built-in over-temperature protection: if the temperature of the MCU or the IGBT temperature sensor (requires additional circuitry) exceeds the limit, the power output is forcibly shut off.

[0084] The IGBT driver circuit has a built-in current sampling resistor to detect the IGBT current in real time. If the current is abnormal (such as a short circuit), the driver circuit triggers a soft shutdown and sends an alarm signal to the MCU to trigger the shutdown protection.

[0085] The bottom sensor works in conjunction with the MCU to input temperature data for power regulation and protection decisions; the MCU and IGBT drive circuit work together to control the IGBT switching with PWM signals; and the MCU and communication interface work together to send real-time data (temperature, power, etc.) or fault codes to the control board.

[0086] After the user issues a command, the communication interface receives the command and transmits it to the MCU to set parameters such as power and mode.

[0087] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A power motherboard based on intermittent heating technology, characterized in that, include: A switching power supply that converts alternating current to direct current and powers the motherboard; A surge protection circuit that shuts down power output when there is a momentary high voltage in the power grid; An IGBT drive circuit that receives PWM control signals from the MCU and drives the IGBT module to operate at high frequency. The MCU control circuit responsible for data acquisition; The bottom-of-the-pot sensor detection circuit is responsible for collecting bottom-of-the-pot temperature data. Provides a programming port for programming MCU programs; Communication interface used to connect the power mainboard and the control board; The switching power supply, MCU control circuit, and IGBT drive circuit are connected in sequence. The programming port, MCU control circuit, and communication interface are connected in sequence. The bottom sensor detection circuit is electrically connected to the MCU control circuit. The surge protection circuit is electrically connected to the MCU control circuit.

2. The power motherboard based on intermittent heating technology according to claim 1, characterized in that: The MCU control circuit includes a chip U3. Pin 5 of the chip U3 is connected to a resistor R26 for receiving data, and pin 6 of the chip U3 is connected to a resistor R27 for transmitting data. One end of the resistor R26 is connected to a jumper interface J12, and one end of the resistor R27 is connected to a jumper interface J13. Pin 13 of the chip U3 is connected to a resistor R127 and a diode D9. Pin 18 of the chip U3 is connected to a capacitor EC105, a capacitor C121, and a resistor R125 arranged in parallel.

3. The power motherboard based on intermittent heating technology according to claim 2, characterized in that: The switching power supply includes a chip U2, a transformer T1, a voltage regulator U5 and a voltage regulator U6 that convert DC voltage to 5V output. Pin 5 of the chip U2 is connected to pin 1 of the transformer T1. Diodes D16 and D17 are connected between pin 4 of the chip U2 and pin 5 of the transformer T1. Diodes D15 and ZD2 are connected between pin 3 of the chip U2 and pin 5 of the transformer T1. The voltage regulator U5 has capacitors EC2, C3 and EC5 connected in parallel between pin 1 and pin 2, and capacitors C102, EC31 and EC6 connected in parallel between pin 2 and pin 3. A capacitor C3A and a capacitor EC4 are connected in parallel between pin 1 and pin 2 of the voltage regulator U6, and a capacitor EC3 and a capacitor 4 are connected in parallel between pin 2 and pin 3 of the voltage regulator U6. A diode D4 is connected to pin 6 of the transformer T1, a resistor R4 is connected to pin 1 of the voltage regulator U5, and a resistor R30 is connected to pin 1 of the voltage regulator U6. The resistors R4 and R30 and the diode D4 are connected together.

4. The power motherboard based on intermittent heating technology according to claim 3, characterized in that: The surge protection circuit includes a rectifier bridge DB1. A capacitor C11 is connected between pins 1 and 2 of the rectifier bridge DB1. A diode D1 and a diode D2 are also connected between pins 1 and 2 of the rectifier bridge DB1. The terminals of diodes D1 and D2 are respectively connected to a resistor R9, a capacitor C13 connected in parallel, and a resistor R10. One end of the resistor R9 is connected to a resistor R13, a capacitor EC1, a capacitor C888, and a capacitor C12 connected in parallel. The terminals of C13 and resistor R10 are connected to a resistor R15. One end of the resistor R15 is connected to a capacitor C15, a diode ZD4, and a series resistor R17 and a resistor R20. The resistor R15 is connected to pin 13 of chip U3. Pin 3 of the rectifier bridge DB1 is connected to pin 17 of chip U3.

5. The power motherboard based on intermittent heating technology according to claim 4, characterized in that: The IGBT driving circuit includes transistors Q7, Q16, and Q103. The emitter of transistor Q7 is connected to the emitter of transistor Q16, the base of transistor Q7 is connected to the base of transistor Q16, the emitter of transistor Q103 is connected to the collector of transistor Q16, and the collector of transistor Q103 is connected to the bases of transistors Q7 and Q16. A resistor R105 and a resistor R126 are connected between the base and collector of the transistor Q7. One end of the resistor R105 is connected to a capacitor EC102 and a capacitor C122 connected in parallel. A resistor R112 is connected to the base of the transistor Q103. A resistor R111 is connected between the resistor R112 and the resistor R105. The resistor R112 is connected to pin 7 of the chip U3.

6. The power motherboard based on intermittent heating technology according to claim 5, characterized in that: The bottom sensor detection circuit includes a connector CN19, with resistors R156 and R22 connected in series at pin 3 of the connector CN19. Resistors R45 and capacitor C27 are connected in parallel at the connection terminals of resistors R156 and R22. The bottom sensor detection circuit also includes a thermistor RT2, with resistors R8 and capacitor C9 connected at its two ends respectively. The bottom sensor detection circuit also includes jumper interface J8 connected to pin 10 of chip U3, jumper interfaces J9 and J13 connected in parallel to pin 12 of chip U3, and jumper interfaces J10 and J16 connected in parallel to pin 11 of chip U3.

7. The power motherboard based on intermittent heating technology according to claim 6, characterized in that: The programming port includes connector CN103, pin 2 of connector CN103 is connected to a 5V power supply, pin 3 of connector CN103 is connected to pin 3 of chip U3, and pin 4 of connector CN103 is connected to pin 4 of chip U3.

8. The power motherboard based on intermittent heating technology according to claim 7, characterized in that: The communication interface includes a connector CN5 and a transistor Q6. Pin 2 of the connector CN5 is connected to the collector of the transistor Q6. A resistor R16 is connected to the base of the transistor Q6. The resistor R16 is connected to a resistor R27. An inductor L2 is connected to pin 3 of the connector CN5. The inductor L2 is connected to a resistor R26. A capacitor C10 is connected between the collector and emitter of the transistor Q6. Pin 2 of the connector CN5 is connected to the collector of the transistor Q6.

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