A power supply control and driving integrated system based on a dough mixer and a working method thereof

Abstract

The application discloses a power control and driving integrated system based on a flour mixing machine and a working method thereof. An AC-DC rectifier filter circuit of a main control board is connected with a DC-DC step-down circuit, a discrete IGBT three-phase bridge circuit and a bus voltage detection circuit of the main control board respectively, the discrete IGBT three-phase bridge circuit is connected with a pre-driving circuit and a driving board main control MCU respectively, the DC-DC step-down circuit of the main control board is connected with the pre-driving circuit, an LDO step-down circuit of the main control board and a cooling fan power supply circuit respectively, the LDO step-down circuit of the main control board is connected with serial communication, the driving board main control MCU and an external interface of the main control board respectively, and the driving board main control MCU is further connected with a sampling signal; the serial communication is connected with a main control MCU of a secondary board, the main control MCU of the secondary board is connected with an external interface of the secondary board and an LDO step-down circuit of the secondary board respectively, the LDO step-down circuit of the secondary board is connected with a DC-DC step-down circuit of the secondary board, and the DC-DC step-down circuit of the secondary board is connected with an AC-DC rectifier filter circuit of the secondary board. The application aims at the problem that a traditional flour mixing machine function circuit is long-term electrified and standby energy consumption is high.

Description

Technical Field

[0001] This invention belongs to the field of control circuit technology, specifically relating to an integrated power control and drive system for a dough mixer and its working method. Background Technology

[0002] As a typical high-power inductive load appliance in modern kitchens, the dough mixer's working mechanism is far more complex than that of ordinary small appliances. In actual operation, it not only has to cope with the drastic resistance changes in the initial stage of mixing dry and wet flour, but also needs to drive a load of hundreds of kilograms of highly viscous dough for extended periods. This special working condition places stringent industrial-grade requirements on the instantaneous burst of motor starting torque, the continuous output stability at rated power, the fatigue resistance of the transmission system, and the overall energy efficiency management of the machine.

[0003] However, most traditional dough mixers on the market today use outdated technologies, revealing numerous pain points: In standby mode, the power module and control system still exhibit high parasitic power consumption; under heavy loads with high-moisture or extra-high-gluten flour, the motor often stalls or even burns out due to insufficient starting torque; during prolonged mixing, the lack of effective thermal management and vector control leads to significant motor temperature rise and thermal decay; furthermore, under the non-linear load impact of dough folding and patting, traditional fixed-frequency drive solutions struggle to maintain a constant speed, resulting in significant speed fluctuations (surge), directly affecting the gluten network expansion rate. These problems not only significantly increase hidden electricity costs for households but also shorten the equipment's lifespan, severely restricting the user experience and the stability of baked goods quality. Summary of the Invention

[0004] This invention provides an integrated power control and drive system for dough mixers and its working method, addressing the problem of traditional dough mixers having long-term energization and high standby power consumption.

[0005] This invention is achieved through the following technical solution: A power control and drive integrated system based on a dough mixer, the system includes a main control board and a sub-board. The main control board provides power to the system and processes logic; the sub-board is connected to the left main control board through a communication interface to realize power distribution and local control. The main control board includes an AC-DC rectifier and filter circuit, a DC-DC step-down circuit, a discrete IGBT three-phase bridge circuit, and a driver board main control MCU. The AC-DC rectifier and filter circuit of the main control board is connected to the DC-DC step-down circuit, the discrete IGBT three-phase bridge circuit, and the bus voltage detection circuit of the main control board, respectively. The discrete IGBT three-phase bridge circuit is connected to the pre-drive circuit and the main control MCU of the driver board, respectively. The DC-DC step-down circuit of the main control board is connected to the pre-drive circuit, the LDO step-down circuit of the main control board, and the cooling fan power supply circuit, respectively. The LDO step-down circuit of the main control board is connected to the serial communication, the main control MCU of the driver board, and the external interface of the main control board, respectively. The main control MCU of the driver board is also connected to the sampling signal. The serial communication is connected to the main control MCU of the control board. The main control MCU of the control board is connected to the external interface of the sub-board and the LDO step-down circuit of the sub-board. The LDO step-down circuit of the sub-board is connected to the DC-DC step-down circuit of the sub-board. The DC-DC step-down circuit of the sub-board is connected to the AC-DC rectifier and filter circuit of the sub-board. The AC-DC rectifier and filter circuit of the main control board converts AC mains power into DC power as the main power source of the system. The DC-DC step-down circuit of the main control board is input to the LDO voltage regulator circuit to further regulate the voltage and output a stable low-voltage DC power. Direct output control circuit power supply: to power the subsequent control MCU and related circuits; The control signal from the LDO regulator circuit is either the feedback signal output by the LDO or the control command after being regulated by the LDO. External commands from the communication interface, feedback from the right sub-board, or commands from the host computer; After processing the signal, the function outputs a control signal to the DC-DC step-down circuit to adjust the output voltage / current, the backup battery circuit to control the charging / discharging logic, and interacts with the right sub-board through the communication interface.

[0006] The beneficial effects of this invention are: This invention revolves around the core design goals of "low power consumption, high reliability, and strong anti-interference." Using a main control MCU as the core, it constructs a complete closed-loop control system encompassing "power supply—drive control—state sampling—feedback adjustment." The overall solution addresses the practical application requirements of dough mixers, such as high load, high torque, and long-term operation. The system's most significant design highlight lies in its low-power optimization concept permeating all functional modules. Through differentiated low-power power supply control schemes, it achieves on-demand power management for non-essential functional modules, effectively reducing standby power consumption and ineffective energy consumption while ensuring functional integrity. Simultaneously, it reduces system heat generation, lowers thermal stress, improves EMC performance, and enhances the long-term operational stability of the entire system and the lifespan of components.

[0007] In terms of human-computer interaction and functional expansion, the system integrates multiple external functional interfaces, enabling functions such as operation status detection, gear adjustment, temperature protection, and auxiliary heat dissipation control, thereby improving the system's ease of operation and engineering adaptability. Simultaneously, the serial communication employs an optocoupler isolation structure, effectively suppressing electromagnetic interference generated during motor drive and improving data transmission stability and system anti-interference capabilities.

[0008] In terms of drive system design, the system adopts a three-phase full-bridge drive structure based on discrete IGBTs. Compared with traditional integrated drive solutions, it has advantages such as flexible component selection, low hardware cost, excellent heat dissipation performance, and easier EMC optimization. Through distributed layout, large-area heat dissipation copper foil, and temperature detection-linked cooling fan control design, local heat concentration can be effectively reduced, improving the long-term reliability of power devices. At the same time, it is more convenient for later maintenance, which helps to reduce system maintenance costs.

[0009] Furthermore, the system employs a multi-stage power supply architecture, combining AC-DC rectification and filtering, DC-DC isolation step-down, and LDO linear regulation modules to achieve a stable, safe, and low-noise power supply. Through dual-resistor differential sampling, independent overcurrent protection sampling, and multi-dimensional status monitoring, it achieves real-time closed-loop control and fault protection of the motor's operating status. Overall, this system demonstrates good comprehensive performance in terms of low power consumption and energy saving, EMC optimization, drive reliability, human-machine interaction, and engineering practicality. It also boasts advantages such as clear structure, controllable cost, convenient maintenance, and ease of mass production, making it highly valuable for practical applications. Attached Figure Description

[0010] Figure 1 This is an overall system block diagram of the present invention.

[0011] Figure 2 This is a circuit diagram of the AC-DC rectifier and filter circuit of the main control board of this invention.

[0012] Figure 3 This is a step-down diagram of the present invention, wherein (a) is the DC-DC step-down circuit of the main control board, and (b) is the LDO step-down circuit of the main control board.

[0013] Figure 4 This is the discrete IGBT three-phase bridge circuit diagram of the present invention.

[0014] Figure 5 This is the pre-drive circuit diagram of the present invention.

[0015] Figure 6 This is the motor interface circuit diagram of the present invention.

[0016] Figure 7 This is a diagram of the main control MCU of the driver board of the present invention.

[0017] Figure 8 This is a circuit diagram of the main control MCU driver detection circuit of the driver board of the present invention, wherein (a) is the programming port circuit, (b) is the cooling fan power supply circuit, (c) is the bus voltage detection circuit, (d) is the IGBT temperature detection circuit, (e) is the motor temperature detection circuit, (f) is the magnetic sensor acquisition circuit, (g) is the serial communication circuit, and (h) is the conditioning circuit.

[0018] Figure 9 This is a circuit diagram of the AC-DC rectifier and filter circuit of the sub-board of the present invention.

[0019] Figure 10 This is the zero-crossing detection circuit diagram of the present invention.

[0020] Figure 11 This is the LDO step-down circuit diagram of the sub-board of the present invention.

[0021] Figure 12 This is a diagram of the subplate of the present invention.

[0022] Figure 13 This is a circuit diagram of the main control MCU driver detection circuit of the secondary board of the present invention, wherein (a) is a Hall switch circuit, (b) is a start switch circuit, (c) is a potentiometer circuit, (d) is a serial communication lamp board 1 circuit, (e) is a serial communication lamp board 2 circuit, (f) is a programming port circuit, and (g) is a serial communication motor board circuit.

[0023] Figure 14 This is the optical coupler isolation diagram for serial communication of the present invention. Detailed Implementation

[0024] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of this application with unnecessary detail.

[0025] It should be understood that, when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0026] It should also be understood that the terminology used in this application specification is for the purpose of describing particular embodiments only and is not intended to limit the application. As used in this application specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0027] The following is in conjunction with the appendix to this application specification. Figure 1-14 The technical solutions in the embodiments of this application are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0028] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0029] Implementation Method 1 This embodiment provides an integrated power control and drive system based on a dough mixer. The system includes a main control board and a sub-board. The main control board provides power to the system and processes logic. The sub-board is connected to the left main control board through a communication interface to realize power distribution and local control. The main control board includes an AC-DC rectifier and filter circuit, a DC-DC step-down circuit, a discrete IGBT three-phase bridge circuit, and a driver board main control MCU. The AC-DC rectifier and filter circuit of the main control board is connected to the DC-DC step-down circuit, the discrete IGBT three-phase bridge circuit, and the bus voltage detection circuit of the main control board, respectively. The discrete IGBT three-phase bridge circuit is connected to the pre-drive circuit and the main control MCU of the driver board, respectively. The DC-DC step-down circuit of the main control board is connected to the pre-drive circuit, the LDO step-down circuit of the main control board, and the cooling fan power supply circuit, respectively. The LDO step-down circuit of the main control board is connected to the serial communication, the main control MCU of the driver board, and the external interface of the main control board, respectively. The main control MCU of the driver board is also connected to the sampling signal. The serial communication is connected to the main control MCU of the sub-board. The main control MCU of the sub-board is connected to the external interface of the sub-board and the LDO step-down circuit of the sub-board. The LDO step-down circuit of the sub-board is connected to the DC-DC step-down circuit of the sub-board. The DC-DC step-down circuit of the sub-board is connected to the AC-DC rectifier and filter circuit of the sub-board.

[0030] The AC-DC rectifier and filter circuit of the main control board converts AC mains power into DC power as the main power source of the system. The DC-DC step-down circuit of the main control board is input to the LDO voltage regulator circuit to further regulate the voltage and output a stable low-voltage DC power. Direct output control circuit power supply: to power the subsequent control MCU and related circuits; The control signal from the LDO voltage regulator circuit is either the feedback signal output by the LDO or the control command after being regulated by the LDO.

[0031] External commands from the communication interface, feedback from the right sub-board, or commands from the host computer.

[0032] After processing the signal, the function outputs a control signal to the DC-DC step-down circuit to adjust the output voltage / current, the backup battery circuit to control the charging / discharging logic, and interacts with the right sub-board through the communication interface.

[0033] As a typical high-power household kitchen appliance, dough mixers require prolonged operation to drive high-viscosity loads, placing high demands on motor starting torque, continuous output capacity, system stability, and overall energy consumption. Traditional dough mixers commonly suffer from high standby power consumption, difficulty starting the motor under heavy loads, overheating during operation, and significant speed fluctuations under complex working conditions. These issues not only increase household electricity consumption but also affect the long-term stability and user experience of the equipment. To address these problems, this system features a specially designed high-voltage, high-power motor drive control system focused on low power consumption and energy saving. This system meets the high-load driving requirements of dough mixers while comprehensively improving system energy efficiency, stability, and reliability.

[0034] This system prioritizes low-power design as its core innovation, with this concept permeating all key functional modules. Addressing the issue of traditional dough mixers' circuitry being constantly powered and consuming high standby power, the system proposes a low-power design approach of "on-demand power supply, tiered control, and power-off when not in operation," and designs differentiated low-power switching control schemes. Specifically, for low-frequency, high-current loads such as head switches, a functional power supply control circuit based on NPN transistors and relays is used to achieve reliable power on / off and low-power management on the load side. For low-voltage, low-power peripherals such as external light boards, a low-power power supply control circuit based on PMOS transistors is used to achieve rapid start / stop of peripheral power supply and near-zero standby power consumption control. The system can dynamically adjust the power supply path according to the operating status of different modules, effectively reducing overall standby power consumption and ineffective energy loss while ensuring normal function operation. This design not only aligns with the current development trend of energy conservation and intelligence in household kitchen appliances but also balances system performance and user experience, achieving a balanced optimization between energy consumption and performance. From a user perspective, low-power design effectively reduces energy consumption in standby, no-load, and light-load conditions, minimizing unnecessary power consumption during long-term use and thus lowering household electricity costs. Simultaneously, lower system power consumption reduces component heating, mitigating the risk of component aging, insulation failure, and abnormal overheating caused by excessive localized temperature rise, further enhancing product safety and long-term operational stability. From a product application and market perspective, low-power design effectively reduces energy consumption, aligning with green, low-carbon, and energy-saving development trends. Furthermore, high energy efficiency and low power consumption have become crucial competitive indicators for home appliances, contributing to enhanced product market competitiveness and solution application value.

[0035] In terms of human-machine interaction and external interface design, the system integrates multiple functional interfaces, including a Hall effect / magnetic sensor interface, a potentiometer level adjustment interface, a start switch interface, a motor temperature detection interface, and a cooling fan power supply interface, to achieve functions such as motor status detection, level adjustment, fixed-point shutdown, temperature protection, and auxiliary heat dissipation. Specifically, the Hall effect / magnetic sensor interface is used for stirring paddle position detection, precise homing, and fixed-point shutdown control, effectively improving user convenience; the potentiometer interface is used for level adjustment, automatically adjusting the motor speed and kneading intensity according to different levels to meet the kneading needs of different doughs; the motor temperature detection interface is used to monitor the motor operating temperature in real time and, combined with protection strategies, improve system operational safety; and the cooling fan interface is used for overall thermal management control, reducing the operating temperature rise of power devices. The overall interface design balances functionality, ease of operation, and engineering adaptability, meeting the human-machine interaction and functional expansion needs of the dough mixer under different operating conditions.

[0036] In terms of drive system design, the system adopts a three-phase full-bridge drive structure based on discrete IGBTs. The power drive unit consists of discrete IGBT power devices and independent pre-drive circuits, enabling precise control of the motor's operation. Compared to traditional integrated power modules, the discrete solution offers greater flexibility in cost control, device selection, heat dissipation layout, and EMC optimization. It allows for targeted configuration of the IGBT's withstand voltage, conduction capability, and switching characteristics based on the actual load characteristics of the dough mixer motor, meeting drive performance requirements while effectively reducing hardware costs. Furthermore, the discrete structure supports distributed power device layout, and combined with large-area heat dissipation copper foil, thermal vias, and independent temperature detection design, it effectively improves system heat dissipation. When the IGBT temperature is detected to be too high, the main control MCU can activate an auxiliary cooling fan via the cooling fan interface to reduce the temperature rise of the power devices and improve system stability. Regarding electromagnetic compatibility, the system can optimize the IGBT switching transient process by adjusting the gate drive resistance and switching speed, reducing voltage and current spikes and high-frequency oscillations, thereby improving EMC rectification flexibility and system anti-interference capabilities. In addition, the system is equipped with comprehensive overcurrent and short-circuit mechanisms, which can provide stable torque output under conditions such as high dough resistance, difficulty in starting, and sudden load changes, ensuring motor starting performance and operational stability, and meeting the high-load operation requirements of the dough mixer.

[0037] Furthermore, in terms of communication design, the system is equipped with multiple serial communication interfaces and incorporates optocoupler isolation technology in the communication link to achieve stable and reliable data interaction between the main control MCU and devices such as the upper control board and host computer. The system can complete functions such as issuing operation commands, providing operation status feedback, and uploading fault information. At the same time, by utilizing the "electrical-optical-electrical" isolation transmission characteristics of optocouplers, electrical isolation between the control end and the peripheral end is achieved, effectively suppressing the impact of electromagnetic interference and voltage spikes generated during motor drive on the communication link, reducing the risk of communication errors and data anomalies, improving the system's communication stability, anti-interference capability, and the safety of the core control circuit, making it more suitable for the long-term stable operation requirements of dough mixers in high-power drive environments.

[0038] The entire system is centered around a main control MCU, constructing a complete closed-loop control system encompassing power supply, drive control, signal acquisition, and feedback adjustment. The main control MCU is responsible for motor drive control, operational data acquisition, algorithm processing, and serial communication. Through internal control algorithms, it performs real-time closed-loop adjustment of motor speed and output status, and combines multi-dimensional sampling data such as phase current and bus voltage to achieve stable and efficient system operation. The hardware architecture focuses on low-power power management and highly reliable motor drive, integrating AC-DC rectification and filtering units, DC-DC isolation buck units, LDO linear regulator units, discrete IGBT three-phase full-bridge drive units, multi-dimensional sampling units, and multi-serial communication units. It covers key functional modules such as dual-resistor differential sampling, independent overcurrent protection sampling, and optocoupler-isolated communication.

[0039] In terms of power supply design, the system supports a wide input range of 100VAC–240VAC, adapting to the operating requirements of different power grid environments. The AC-DC power supply section adopts a dual magnetic ring and dual X capacitor combination structure, combined with varistors and dual NTC thermistors, effectively improving the system's EMC performance and surge protection capabilities. The DC-DC circuit adopts a high-efficiency BUCK architecture, providing stable power supply to peripheral functional modules while reducing PCB footprint. The LDO regulator section provides low-ripple, low-noise power to the MCU and sampling circuit, ensuring stable operation of the control system and signal acquisition system. The overall system combines a comprehensive protection mechanism, low-power architecture, and multi-level power supply design, achieving a balance between overall energy consumption optimization and engineering practicality while ensuring system safety, stability, and anti-interference capabilities.

[0040] Furthermore, the AC-DC rectifier and filter circuit of the main control board includes a fuse F1. One end of the fuse F1 is connected to terminal 1 of interface CN1. The other end of the fuse F1 is connected to the live wire AC-L, one end of resistor RX1, one end of varistor RV1, one end of safety capacitor CX1, and terminal 2 of boost inductor LL1. Terminal 1 of boost inductor LL1 is connected to one end of safety capacitor CX2, one end of resistor RX4, and terminal 2 of boost inductor LL2. The other end of resistor RX4 is connected to one end of resistor RX6, and the other end of resistor RX6 is connected to one end of resistor RX7. Terminal 1 of boost inductor LL2 is connected to one end of safety capacitor CX3, one end of capacitor CY2, one end of resistor RX3, terminal 1 of thermistor NTC2, and the other end of the thermistor CY2. Terminal 1 of resistor NTC1 is connected to the circuit. The other end of resistor RX3 is connected to one end of resistor RX5. The other end of resistor RX5 is connected to one end of resistor RX2. Terminal 2 of the thermistor NTC2 is connected to terminal 2 of the thermistor NTC1 and terminal 2 of the bridge circuit. Terminal 3 of the bridge circuit is connected to the other end of resistor RX2, one end of capacitor CY1, the other end of safety capacitor CX3, and terminal 4 of boost inductor LL2. Terminal 3 of boost inductor LL2 is connected to the other end of safety capacitor CX2, the other end of resistor RX7, and terminal 4 of boost inductor LL1. Terminal 3 of boost inductor LL1 is connected to the other end of safety capacitor CX1, the other end of varistor RV1, the other end of resistor RX1, neutral terminal AC-N, and terminal 2 of interface CN1. Terminal 1 of the bridge circuit is connected to the positive terminals of output capacitors EC4, EC5, and EC6, one end of capacitor CBB1, one end of resistor R65, one end of capacitor CY3, and the operating voltage 310V. Terminal 4 of the bridge circuit is connected to the negative terminals of output capacitors EC4, EC5, and EC6, the other end of capacitor CBB1, one end of resistor R55, and one end of capacitor CY4, and then grounded. The other ends of resistors R65 and R55 are connected. The other end of capacitor CY2 is connected to the other end of capacitor CY1, terminal 3 of interface CN1, and one end of differential mode inductor LL4, respectively. The other end of capacitor CY3 is connected to the other end of capacitor CY4 and the other end of differential mode inductor LL4, respectively.

[0041] Furthermore, the GUH terminals of the discrete IGBT three-phase bridge circuit are respectively connected to one end of resistor R72, one end of capacitor C27, one end of resistor R75, and the G terminal of MOSFET Q4 in the pre-drive circuit. The other end of capacitor C27 is respectively connected to the other end of resistor R75, the S terminal of MOSFET Q4, the D terminal of MOSFET Q8, the 3rd terminal of motor interface L3, the 6th terminal of chip U8 in the pre-drive circuit, and one end of capacitor C15 in the pre-drive circuit. The GUL terminals of the discrete IGBT three-phase bridge circuit are respectively connected to one end of resistor R73, one end of capacitor C32, one end of resistor R67, and the G terminal of MOSFET Q8 in the pre-drive circuit. The other end of capacitor C32 is respectively connected to the other end of resistor R67, the S terminal of MOSFET Q8, and one end of resistor R36. The GVH terminals of the discrete IGBT three-phase bridge circuit are respectively connected to one end of resistor R70, one end of capacitor C21, one end of resistor R61, and the G terminal of MOSFET Q6 in the pre-drive circuit. The other end of capacitor C21 is respectively connected to the other end of resistor R61, the S terminal of MOSFET Q6, the D terminal of MOSFET Q9, terminal 2 of motor interface L3, terminal 6 of chip U9 in the pre-drive circuit, and one end of capacitor C16 in the pre-drive circuit. The GVL terminals of the discrete IGBT three-phase bridge circuit are respectively connected to one end of resistor R71, one end of capacitor C31, one end of resistor R66, and the G terminal of MOSFET Q9 in the pre-drive circuit. The other end of capacitor C31 is respectively connected to the other end of resistor R66, the S terminal of MOSFET Q9, and one end of resistor R35. The GWH terminal of the discrete IGBT three-phase bridge circuit is connected to one end of resistor R68, one end of capacitor C22, one end of resistor R74, and the gate terminal of MOSFET Q7 in the pre-drive circuit. The other end of capacitor C22 is connected to the other end of resistor R75, the source terminal of MOSFET Q7, the drain terminal of MOSFET Q10, terminal 1 of motor interface L3, terminal 6 of chip U10 in the pre-drive circuit, and one end of capacitor C17 in the pre-drive circuit. The GWL terminal of the discrete IGBT three-phase bridge circuit is connected to one end of resistor R69, one end of capacitor C34, one end of resistor R56, and the gate terminal of MOSFET Q10 in the pre-drive circuit. The other end of capacitor C34 is connected to the other end of resistor R56, the source terminal of MOSFET Q10, one end of resistor R39, the other end of resistor R36, and the other end of resistor R35. The other end of resistor R39 is grounded.

[0042] Furthermore, terminal 4 of the motor interface L3 is connected to one end of capacitor C23 and terminal 1 of the MOTO interface, terminal 5 of the motor interface L3 is connected to one end of capacitor C20 and terminal 3 of the MOTO interface, terminal 6 of the motor interface L3 is connected to one end of capacitor C19 and terminal 5 of the MOTO interface, and the other end of capacitor C23 is connected to the other ends of capacitor C20 and capacitor C19 and then grounded.

[0043] Furthermore, the other end of resistor R72 in the pre-drive circuit is connected to terminal 7 of chip U8, the other end of resistor R73 in the pre-drive circuit is connected to terminal 5 of chip U8, and the other end of capacitor C15 in the pre-drive circuit is connected to terminal 8 of chip U8; terminal 1 of chip U8 is connected to one end of capacitor C43 and the 15VOUT terminal respectively, the other end of capacitor C43 is grounded, terminal 2 of chip U8 is connected to terminal 3 of the main control MCU of the driver board after series resistor R22, terminal 3 of chip U8 is connected to terminal 4 of the main control MCU of the driver board after series resistor R23, and terminal 4 of chip U8 is grounded; The other end of resistor R70 in the pre-drive circuit is connected to terminal 7 of chip U9; the other end of resistor R71 in the pre-drive circuit is connected to terminal 5 of chip U9; the other end of capacitor C16 in the pre-drive circuit is connected to terminal 8 of chip U9; terminal 1 of chip U9 is connected to one end of capacitor C33 and the 15VOUT terminal respectively; the other end of capacitor C33 is grounded; terminal 2 of chip U9 is connected to terminal 5 of the main control MCU of the driver board after series connection with resistor R26; terminal 3 of chip U9 is connected to terminal 6 of the main control MCU of the driver board after series connection with resistor R27; and terminal 4 of chip U9 is grounded. The other end of resistor R68 in the pre-drive circuit is connected to terminal 7 of chip U10, the other end of resistor R69 in the pre-drive circuit is connected to terminal 5 of chip U10, and the other end of capacitor C17 in the pre-drive circuit is connected to terminal 8 of chip U10. Terminal 1 of chip U10 is connected to one end of capacitor C11 and the 15VOUT terminal, respectively. The other end of capacitor C11 is grounded. Terminal 2 of chip U10 is connected to terminal 7 of the main control MCU of the driver board after being connected in series with resistor R28. Terminal 3 of chip U10 is connected to terminal 8 of the main control MCU of the driver board after being connected in series with resistor R29. Terminal 4 of chip U10 is grounded.

[0044] Furthermore, terminal 2 of the main control MCU of the driver board is connected to one end of resistor R58, one end of resistor R48, and one end of capacitor C36 of the bus voltage detection circuit, respectively. The other end of resistor R58 and capacitor C36 of the bus voltage detection circuit are connected to ground. The other end of resistor R48 is connected to one end of resistor R44 of the bus voltage detection circuit. The other end of resistor R44 is connected to a voltage of +310V. The 9th terminal of the main control MCU of the driver board is connected to one end of resistor R38 and one end of capacitor C24 respectively. The 10th terminal of the main control MCU of the driver board is connected to one end of resistor R32 and the other end of capacitor C24 respectively. The other end of resistor R32 is connected to one end of resistor R39 of the discrete IGBT three-phase bridge circuit. The 11th terminal of the main control MCU of the driver board is connected to one end of resistor R63 and one end of capacitor C26 respectively. The 12th terminal of the main control MCU of the driver board is connected to one end of resistor R64 and the other end of capacitor C26 respectively. The other end of resistor R63 is connected to one end of resistor R39 of the discrete IGBT three-phase bridge circuit. The 13th terminal of the main control MCU of the driver board is connected to one end of resistor R40, one end of the thermistor NTC and one end of capacitor C38 respectively. The other end of resistor R40 is connected to the working voltage 5V, and the other end of the thermistor NTC and the other end of capacitor C38 are connected to ground. The 14th terminal of the main control MCU of the driver board is connected to the 4th terminal of interface CN2, the 15th terminal of the main control MCU of the driver board is connected to the 3rd terminal of interface CN2, the 2nd terminal of interface CN2 is grounded, and the 1st terminal of interface CN2 is connected to the working voltage of 5V. The 16th pin of the main control MCU of the driver board is connected to one end of the resistor R53 of the programming port, and the other end of the resistor R53 is connected to the 2nd pin of the JATG1 interface of the programming port. The 17th pin of the main control MCU of the driver board is connected to one end of the resistor R59 of the programming port, and the other end of the resistor R59 is connected to the 3rd pin of the JATG1 interface of the programming port. The 1st pin of the JATG1 interface is connected to the working voltage of 5V, and the 4th pin of the JATG1 interface is grounded. The 18th terminal of the main control MCU of the driver board is connected to one end of capacitor C30, the 20th terminal of the main control MCU of the driver board is connected to one end of capacitor C29, the 22nd terminal of the main control MCU of the driver board is connected to one end of capacitor C28, and the other end of capacitor C30 is connected to the other end of capacitor C29, the other end of capacitor C28, the 19th terminal of the main control MCU of the driver board, and the 21st terminal of the main control MCU of the driver board and then grounded. The 20th terminal of the main control MCU on the driver board is also connected to the LDO step-down circuit of the main control board. The LDO step-down circuit of the main control board includes a capacitor C12. The positive terminal of the capacitor C12 is connected to one end of the capacitor C14 and the 1st terminal of the chip Z1. The 3rd terminal of the chip Z1 is connected to one end of the capacitor C13, one end of the resistor R50, and one end of the resistor R54. The other end of the capacitor C13 is connected to the 2nd terminal of the chip Z1, the other end of the capacitor C14, and the negative terminal of the capacitor C12 and then grounded. The other end of the resistor R50 is connected to the other end of the resistor R54 and then connected to the DC-DC step-down circuit of the main control board. The 21st pin of the main control MCU of the driver board is also connected to one end of the motor temperature detection resistor R7 and one end of the motor temperature detection capacitor C3. The other end of the motor temperature detection resistor R7 is connected to one end of the motor temperature detection resistor R6 and the 2nd pin of the motor temperature detection interface CN4. The other end of the motor temperature detection capacitor C3 is connected to the 1st pin of the motor temperature detection interface CN4 and then grounded. The other end of the motor temperature detection resistor R6 is connected to the working voltage 5V. The 22nd pin of the main control MCU of the driver board is connected to one end of the resistor R8 of the electromagnetic sensor, the other end of the resistor R8 of the electromagnetic sensor is connected to the 2nd pin of interface CN3, the 1st pin of interface CN3 is connected to the working voltage 5V, and the 3rd pin of interface CN2 is grounded. The 24th terminal of the main control MCU on the driver board is connected to one end of resistor R3 and one end of capacitor C2, respectively. The other end of capacitor C2 is grounded, and the other end of resistor R3 is connected to one end of resistor R39 of the discrete IGBT three-phase bridge circuit.

[0045] Furthermore, the DC-DC step-down circuit of the main control board includes chip U2. Terminals 5-8 of chip U2 are connected to one end of resistor R2 and the positive terminal of capacitor EC1. The other end of resistor R2 is connected to 310V. The negative terminal of capacitor EC1 is connected to the positive terminal of diode D2, the positive terminal of Zener diode ZD1, one end of resistor R5, the negative terminal of capacitor EC2, and one end of capacitor C1. The negative terminal of diode D2 is connected to terminal 1 and terminal 2 of chip U2 and one end of differential mode inductor L1. The other end of differential mode inductor L1 is connected to the positive terminal of capacitor EC2, the other end of resistor R5, one end of resistor R4, the negative terminal of Zener diode ZD1, the positive terminal of diode D1, and 15V. The negative terminal of diode D1 is connected to terminal 4 of chip U2. The other end of resistor R4 is connected to the other end of capacitor C1 and the 15VOUT terminal.

[0046] Furthermore, the AC-DC rectifier and filter circuit of the sub-board includes a fuse F2. One end of the fuse F2 is connected to the ACL terminal, and the other end of the fuse F2 is connected to one end of the varistor RV2, one end of the capacitor CX5, one end of the resistor RX8, and terminal 2 of the common-mode inductor LL3. The other end of the resistor RX8 is connected to one end of the resistor RX10, and the other end of the resistor RX10 is connected to one end of the resistor RX12. The other end of the resistor RX12 is connected to terminal 3 of the common-mode inductor LL3, the other end of the capacitor CX5, the other end of the varistor RV2, and the ACN terminal. Terminal 1 of the common-mode inductor LL3 is connected to one end of resistor R51 of the zero-crossing detection module, terminal 5 of relay K1, one end of resistor CY5, and terminal 1 of the thermistor NTC3. Terminal 6 of relay K1 is connected to terminal 3 of head-up switch CN13. Terminal 1 of head-up switch CN13 is connected to terminal 3 of head-up switch CN6. Terminal 2 of head-up switch CN6 is connected to terminal 3 of relay K1. Terminal 1 of head-up switch CN6 is connected to the other end of resistor CY5, one end of resistor CY6, and the PE terminal. The other end of resistor CY6 is connected to terminal 4 of the common-mode inductor LL3. The circuit consists of: terminal 1 of the circuit, terminal 4 of the relay K1, one end of the capacitor CX4, one end of the resistor RX13, and terminal 3 of the bridge circuit BD2; terminal 2 of the thermistor NTC3, which is connected to the other end of the capacitor CX4, one end of the resistor RX9, and terminal 2 of the bridge circuit BD2; the other end of the resistor RX13, which is connected to one end of the resistor RX11; the other end of the resistor RX11, which is connected to the other end of the resistor RX9; terminal 1 of the bridge circuit BD2, which is connected to one end of the resistor R1 of the LDO step-down circuit on the sub-board and the positive terminal of the capacitor EC3; and terminal 4 of the bridge circuit BD2, which is connected to the negative terminal of the capacitor EC3 and then grounded. Terminal 8 of relay K1 is connected to the anode of diode D3 and the collector of transistor Q1. The emitter of transistor Q1 is connected to one end of resistor R13 and then grounded. The base of transistor Q1 is connected to the other end of resistor R13 and one end of resistor R12. The other end of resistor R12 is connected to terminal 4 of the main control MCU on the sub-board. Terminal 1 of relay K1 is connected to the 5V operating voltage and the cathode of diode D3.

[0047] Furthermore, the other end of resistor R51 in the zero-crossing detection module is connected to one end of resistor R52, the other end of resistor R52 is connected to one end of resistor R49, the other end of resistor R49 is connected to one end of resistor R60, one end of capacitor C35, and the B end of transistor Q3, the C end of transistor is connected to one end of resistor R47 and one end of resistor R46, the other end of resistor R46 is connected to the 5V operating voltage, the E end of transistor is connected to the other end of resistor R60, the other end of capacitor C35, and one end of capacitor C25 and then grounded, and the other end of resistor R47 is connected to the other end of capacitor C25 and the 28th terminal of the main control MCU of the sub-board. The main control MCU of the sub-board is connected to terminal 6 of the serial communication light board 1, terminal 20 of the main control MCU of the sub-board is connected to the serial communication light board 1, and terminal 21 of the main control MCU of the sub-board is connected to the serial communication light board 1. The 9th terminal of the main control MCU of the sub-board is connected to the LED board 2 for serial communication, the 10th terminal of the main control MCU of the sub-board is connected to the LED board 2 for serial communication, and the 15th terminal of the main control MCU of the sub-board is connected to the LED board 2 for serial communication. The main control MCU of the sub-board is connected to a potentiometer at pin 11; the main control MCU of the sub-board is connected to a Hall switch at pin 16; the main control MCU of the sub-board is connected to a power switch at pin 17; the main control MCU of the sub-board is connected to a programming port at pin 25; and the main control MCU of the sub-board is also connected to a programming port at pin 26. The 25th pin of the main control MCU on the sub-board is also connected to the serial communication optical isolation, and the 26th pin of the main control MCU on the sub-board is also connected to the serial communication optical isolation. Furthermore, the serial communication optocoupler isolation is connected to the electrode plate serial communication.

[0048] Low-power switching control: In traditional dough mixer control systems, problems such as functional modules being constantly powered, high standby power consumption, and the inability to supply power to external loads on demand are common. These issues not only increase overall energy consumption but also easily lead to long-term overheating and reduced lifespan of components. Therefore, this paper takes low-power design as the core innovation direction of the system and proposes a low-power switching control scheme with differentiated load management to achieve on-demand power supply and dynamic power management for system functional modules. The overall design adopts the concept of "on-demand power supply, hierarchical control, and power-off when not in operation," achieving precise low-power control of load circuits according to the power supply needs of different loads. In traditional small household appliance systems, some functional circuits remain powered even when not in operation, easily generating continuous standby power consumption. This not only increases energy waste but also causes long-term overheating of components, affecting the stability and lifespan of the entire machine. To address these problems, this system designs differentiated low-power switching control circuits based on the operating characteristics of different loads, achieving dynamic management of power supply to functional modules and peripherals, effectively reducing overall system energy consumption while ensuring normal operation. Specifically, it is divided into two parts: low-power control of head-up switches based on NPN transistors and relays, and low-power control of external lamp boards based on PMOS transistors.

[0049] In the head-up switch control section, the system uses an NPN transistor as the core driver device, paired with a relay to form a switch control circuit, specifically for controlling the on / off state of the head-up switch of the dough mixer, achieving low-power start / stop of the load circuit. The NPN transistor, as the control-level driver device, is driven to conduct and cut off by the MCU output control signal; the relay is responsible for the actual on / off control of the load power supply. The main control unit (MCU) outputs a control signal to the base of the NPN transistor. When the base receives a high-level signal, the transistor saturates and conducts, forming a stable voltage difference across the relay coil. The coil is energized, generating electromagnetic attraction, driving the relay contacts to close, thus providing stable power to the load circuit corresponding to the head-up switch. When the main control unit outputs a low-level signal, the transistor cuts off, the relay coil is de-energized, the electromagnetic attraction disappears, the contacts reset and open, and the load circuit is de-energized, achieving low-power shutdown of the head-up switch and minimizing energy consumption.

[0050] Compared to solutions that directly use an MCU to drive the load or use a regular MOSFET to keep it continuously conducting, this structure can completely cut off the load power supply in the system standby state, reducing static power consumption from the source. Meanwhile, the NPN transistor requires a lower drive voltage to turn on and can be directly driven by the MCU I / O port without the need for an additional boost circuit, further reducing power consumption in the control loop. Furthermore, the relay has strong immunity to electromagnetic interference generated by the internal motor drive of the dough mixer, improving system stability and reliability, and is suitable for control scenarios with low-frequency, high-current loads.

[0051] In the external lamp board control section, the system uses a PMOS transistor as the core switching device, specifically for power supply control of the external lamp board of the dough mixer, realizing low-power start / stop and stable power supply for the lamp board. The MCU outputs a control signal to the gate of the PMOS transistor. When the gate receives a low-level signal, the PMOS transistor turns on, and the 5V power supply voltage is delivered to the external lamp board through the PMOS transistor, and the lamp board lights up normally. When the gate of the PMOS transistor receives a high-level control signal from the MCU, the PMOS transistor turns off, the power supply circuit is disconnected, and the external lamp board is powered off and turns off, realizing low-power shutdown of the external lamp board and adapting to the intermittent lighting characteristics of the dough mixer lamp board.

[0052] Compared to traditional PNP transistors, PMOS transistors offer advantages such as low on-resistance, low voltage drop, and low leakage current. Since external lamp boards are low-voltage, low-power loads, they require high power supply stability. The extremely low voltage drop of a PMOS transistor when turned on ensures a stable power supply to the lamp board, preventing abnormal brightness or instability caused by excessive voltage drop. Simultaneously, the extremely low leakage current of a PMOS transistor when turned off effectively avoids residual power consumption after power failure, better meeting low-power design requirements. Furthermore, PMOS transistors are voltage-controlled devices with fast switching speeds and no mechanical contact losses, meeting the frequent start-stop requirements of lamp boards and reducing power supply disturbances and noise interference during switching.

[0053] Through the two differentiated low-power control schemes described above, the system achieves hierarchical power supply and on-demand management for different functional modules, enabling the equipment to dynamically adjust the power supply path according to the actual operating status, thereby effectively reducing standby power consumption and ineffective energy consumption. Simultaneously, the low-power design also reduces system heat generation and thermal stress, minimizes high-frequency noise and electromagnetic interference, and improves the overall thermal stability, electromagnetic compatibility performance, and long-term operational reliability, providing a solid hardware foundation for the energy-saving and highly reliable operation of the dough mixer system.

[0054] External Interfaces: Based on the optimization of low power consumption of the system, in order to further improve the human-machine interaction capability, operation control accuracy and functional expandability of the dough mixer, the system is designed with a variety of external functional interfaces to realize functions such as motor status detection, gear adjustment, temperature monitoring and auxiliary heat dissipation control, so as to meet the actual application needs of the dough mixer under different operating conditions.

[0055] The Hall effect sensor interface and magnetic sensor interface serve as the core position detection modules of the dough mixer, used for motor rotor position detection and stirring paddle angle return control, respectively. During motor operation, the Hall effect sensor collects the motor rotor position signal in real time, providing commutation and speed feedback to the main control MCU. Simultaneously, the magnetic sensor detects the current angle state of the stirring paddle and feeds the position information back to the main control unit. When the dough mixing process ends or the user triggers a stop command, the main control MCU uses the angle signal fed back from the magnetic sensor to precisely decelerate and stop the motor at a fixed point, ensuring the stirring paddle remains stably in the preset position. This design effectively solves the problem of random stopping angles in traditional dough mixers, facilitating subsequent equipment cleaning and dough removal, while avoiding operational inconvenience or mechanical interference caused by the non-fixed position of the stirring paddle, thus improving the overall human-machine interface and control precision.

[0056] The motor temperature detection interface is used to monitor the motor's operating temperature in real time. It continuously samples the temperature of the motor windings and casing and feeds the temperature signal back to the main control system. When the detected temperature exceeds a preset safety threshold, the system automatically triggers an over-temperature protection strategy. This strategy prevents the motor from suffering insulation aging, performance degradation, or even component damage due to prolonged heavy-load operation by reducing output power or stopping operation, thereby improving the operational safety and long-term reliability of the motor and the entire system.

[0057] The potentiometer interface uses a rotary knob adjustment structure, serving as the core input interface for adjusting the dough mixer's operating speed and kneading intensity. Users rotate the potentiometer to change the output analog voltage signal. The main control MCU identifies the corresponding operating speed based on the sampled signal and automatically adjusts the motor speed and output torque. Different speeds correspond to different kneading intensities and operating speeds: higher speeds result in higher motor speeds and stronger kneading, suitable for high-gluten doughs or rapid kneading scenarios; lower speeds provide gentler motor operation, suitable for low-gluten doughs or fine kneading needs. This design can meet the diverse kneading intensity and softness requirements of different types of dough, improving the machine's adaptability and user operational flexibility.

[0058] The cooling fan power supply interface provides stable power to the auxiliary cooling fan, enabling overall thermal management control. During prolonged operation or high-load conditions, the main control MCU can control the cooling fan to start via this interface based on the motor temperature and power device temperature rise status. This accelerates heat dissipation from the equipment, reduces the operating temperature of the motor and power devices, thereby improving system stability and extending device lifespan. Once the system temperature returns to a safe range, the fan automatically stops, ensuring effective heat dissipation while maintaining low power consumption.

[0059] This invention introduces the design of multiple external interfaces for a dough mixer system, realizing functions such as motor position detection, fixed-point stop of the mixing paddle, gear adjustment, temperature protection, and auxiliary heat dissipation. Through the coordinated operation of multiple interfaces, the system not only improves the convenience of human-machine interaction and the precision of operation control, but also enhances functional expansion capabilities and engineering adaptability, providing a solid hardware foundation for the stable, efficient, and reliable operation of the dough mixer.

[0060] Three-phase bridge circuit based on discrete IGBTs: Besides low-power control and human-machine interface design, the stability and power output capability of the motor drive system are also important components of the dough mixer control system. Considering the characteristics of the dough mixer—high starting load, high operating torque requirements, and long-term operation—this paper adopts a three-phase full-bridge drive scheme based on discrete IGBTs to improve the system's drive capability, heat dissipation performance, and EMC optimization flexibility.

[0061] This system employs a three-phase bridge drive circuit based on discrete IGBTs as the core of the motor power drive, consisting of six discrete IGBT power devices and three pre-drive units. After the main control MCU outputs a PWM control signal, the pre-drive circuit amplifies the drive capability, performs level conversion, and isolates the upper and lower bridge arm drives. Then, it precisely controls the on / off state of the IGBTs in the upper and lower bridge arms of the three-phase bridge, thereby achieving stable adjustment of the speed and output torque of the dough mixer motor, meeting the high load, high torque, and wide speed range operation requirements of the dough mixer.

[0062] The pre-drive circuit, as a crucial interface unit between the MCU and power devices, serves two main purposes. First, it enhances the driving capability of the PWM drive signal, ensuring sufficient gate drive current for the IGBT during switching and improving turn-on and turn-off speeds. Second, it regulates the IGBT's switching speed, optimizing the switching transient process in conjunction with the gate resistor. This reduces switching losses and electromagnetic interference, improving system stability and EMC performance. Furthermore, the pre-drive circuit strengthens the anti-interference capability between the MCU control and power drive terminals, preventing high-frequency noise from the power circuit from affecting the main control system.

[0063] Compared to traditional integrated power module solutions, discrete IGBT structures offer significant advantages in cost control. Under the same voltage level, rated current, and drive topology, the overall cost of a discrete solution is typically lower than that of an integrated module. The voltage withstand capability, current capacity, and switching characteristics of the IGBT can be specifically selected based on the actual operating parameters of the power supply, avoiding the cost waste caused by redundant parameters in integrated modules, thus effectively reducing system hardware costs. Furthermore, the discrete structure offers greater ease of maintenance. When a power device fails due to abnormal operating conditions, it is not necessary to replace the entire drive module; only the corresponding IGBT device needs to be replaced to restore system operation, significantly reducing subsequent maintenance costs and repair complexity.

[0064] In terms of thermal management design, discrete IGBT solutions offer greater layout flexibility. The system can be distributed according to the heat generation of each power device, and the heat conduction path can be optimized by combining large-area heat dissipation copper foil, thermal vias, and external heat dissipation structures. This reduces local heat accumulation, decreases device temperature rise, and improves the thermal stability and reliability of the system under long-term heavy-load operation. This design is more suitable for the continuous thermal load conditions caused by the long-term high-torque operation of dough mixers.

[0065] Most importantly, in terms of electromagnetic compatibility (EMC) optimization, the discrete IGBT drive structure offers superior parameter adjustment capabilities. The system can precisely control the IGBT's switching transients by adjusting the gate drive resistor, drive current, and switching speed, effectively suppressing voltage spikes, current surges, and high-frequency oscillations generated during switching, reducing electromagnetic radiation and conducted interference, and improving the flexibility and controllability of system EMC remediation. Combined with a reasonable PCB power layout and drive circuit design, the overall system's anti-interference capability and operational stability in complex motor drive environments can be further enhanced.

[0066] Overall, this discrete IGBT three-phase bridge drive solution has advantages such as controllable cost, excellent heat dissipation performance, strong EMC adjustability and convenient maintenance. While meeting the high power drive requirements of the dough mixer, it further improves the system's engineering implementation capability and long-term operational reliability.

[0067] Optical isolation for serial communication: Because the dough mixer contains a motor drive unit, high-power switching devices, and a high-voltage power supply module, it is prone to strong electromagnetic interference during system operation. To improve the stability of the communication link and the safety of the control system, this paper introduces optical isolation design into the serial communication circuit to achieve electrical isolation and interference-resistant transmission between the main control MCU and peripherals.

[0068] The core principle of this design is to utilize the "electric-to-optical-to-electrical" conversion characteristics of optocouplers to achieve electrical-free transmission of communication signals. This design uses optical signals as an intermediate medium to electrically isolate the main control MCU from external serial communication devices, retaining only the signal transmission function. This avoids the formation of a direct electrical loop between the two circuits, improving system communication reliability and anti-interference capabilities.

[0069] The operation of optocoupler-isolated communication mainly consists of three stages. The first stage is the electro-optical conversion stage: the serial communication signal output from the main control MCU is connected to the LED at the input of the optocoupler. When the input signal level changes, the LED correspondingly turns on or off, converting the input electrical signal into an optical signal. The second stage is the optical signal isolation transmission stage: the optocoupler uses a sealed optical coupling structure, with no direct electrical connection between the light-emitting and receiving devices. Information is transmitted only through internal optical signals, achieving complete electrical isolation between the control end and the peripheral end, while reducing the impact of external electromagnetic interference on the communication link. The third stage is the photoelectric conversion stage: the phototransistor at the output of the optocoupler conducts after receiving the optical signal and restores the corresponding level signal output; when there is no optical signal input, the phototransistor turns off, thus completing the conversion from optical signal to electrical signal and achieving synchronous transmission of serial data. Throughout the entire process, the input and output signals remain consistent, without affecting the baud rate and data integrity of the serial communication.

[0070] Compared to traditional unisolated serial communication solutions, optocoupler isolation design significantly improves the system's anti-interference capability and electrical safety. Because the dough mixer contains a motor drive unit, discrete IGBT power devices, and high-voltage switching circuits, it is prone to generating strong electromagnetic interference and voltage spikes during operation. If the communication link is not isolated, interference signals may couple to the MCU control terminal through the serial port line, leading to communication errors, data anomalies, or even system malfunctions. Using optocoupler isolation effectively cuts off the electrical coupling path between the control terminal and peripheral devices, reducing the risk of electromagnetic interference being conducted to the main control system through the communication line, and ensuring the stable transmission of critical data such as operating commands, speed data, and temperature sampling information.

[0071] Furthermore, optocoupler isolation can effectively improve system hardware security. Under complex operating conditions, peripheral devices may experience transient overvoltages, current surges, or ground potential differences. Traditional direct-connect communication methods can easily couple abnormal voltages directly to the MCU or serial port chip, increasing the risk of damage to core components. Optocoupler isolation, on the other hand, blocks abnormal current paths through physical isolation, effectively protecting the main control system, reducing the probability of hardware failure, and improving the long-term reliability of the entire machine. It is more suitable for the complex working environment of high-power kitchen appliances such as dough mixers.

[0072] Main Control MCU: After completing low-power control, external interface design, and drive system design, the system also needs to have unified data processing and control capabilities. Therefore, this paper uses the main control MCU as the core control unit of the whole machine, responsible for motor drive control, operation status acquisition, closed-loop algorithm calculation, and communication data interaction, so as to realize the coordinated operation between various functional modules.

[0073] The system employs serial communication to achieve bidirectional data interaction between the main control MCU and the upper control board. The main control MCU receives operating commands from the upper control board in real time, decodes and processes these commands, and precisely controls the motor's running time, speed, and operating status according to the set parameters, ensuring that the motor output remains consistent with the user's settings. Simultaneously, the main control MCU continuously collects key status parameters during system operation, including motor phase current, bus voltage, real-time motor speed, motor output power, and power module temperature, and feeds back the operating status data and fault codes to the upper control board in real time. This enables system operation status monitoring, anomaly alarms, and fault diagnosis, thereby ensuring the stable and safe operation of the dough mixer.

[0074] In terms of motor control, the main control MCU outputs PWM drive signals through internal control algorithms to perform closed-loop regulation of motor speed and output torque. The system sampling section adopts a design scheme that combines dual-resistor differential sampling with independent overcurrent protection sampling. R35 and R36 form a dual-resistor differential sampling circuit for real-time acquisition of motor phase current; R39 serves as an independent sampling resistor, specifically used for overcurrent and short-circuit fault detection, achieving independence between control sampling and protection sampling, thus improving system safety and reliability.

[0075] In the specific operation process, the main control MCU collects the differential voltage signal across R35 and R36. This signal is amplified by the MCU's internal operational amplifier and then input to the ADC module for analog-to-digital conversion. Subsequently, the MCU calculates and processes the sampled data using its internal algorithm to obtain the actual phase current value of the motor. Combined with the current bus voltage and the set speed parameters, the MCU dynamically closes the motor output to achieve stable motor operation. The formula for calculating the differential sampling current of the dual resistors is shown in equation (1): (1) in, This represents the actual value of the motor phase current. The AD value is obtained by ADC sampling; This is the ADC reference voltage; This represents the maximum sampled value of the ADC at the reference voltage. This represents the amplification factor of the operational amplifier. This is the equivalent resistance value after the two resistors R35 and R36 are connected in parallel.

[0076] Compared to traditional single-resistor sampling, dual-resistor differential sampling offers higher sampling accuracy and better anti-interference capabilities. Differential sampling effectively suppresses common-mode noise interference and reduces the impact of high-frequency noise during motor drive on the sampling signal, thereby improving phase current detection accuracy and making it more suitable for operating environments with large load fluctuations, such as dough mixers. Simultaneously, the parallel dual-resistor structure distributes sampling power consumption across the two resistors, reducing temperature rise and thermal stress in a single resistor and improving the long-term operational stability of the sampling circuit. Furthermore, control sampling and overcurrent protection sampling are independent, preventing a single sampling fault from simultaneously affecting control and protection functions, further enhancing system safety redundancy.

[0077] The bus voltage sampling section employs a resistor divider circuit design. Resistors R44, R48, and R58 together form a bus voltage divider network, converting the high-voltage bus voltage into a low-voltage signal compatible with the MCU ADC input range. The main control MCU samples the divided voltage signal using the ADC and calculates the actual bus voltage value internally, providing reliable data support for system closed-loop control, undervoltage protection, and overvoltage protection functions. The bus voltage calculation formula is shown in equation (2): (2) in, This is the actual value of the bus voltage; The bus voltage divider AD value obtained from ADC sampling; This is the ADC reference voltage; It is the maximum sampled value of the ADC; is the bus voltage divider resistor, where is the sampling voltage divider resistor closest to ground. To be connected in series at the bus end with The voltage divider resistors between the three components are connected in series to form a complete voltage divider circuit.

[0078] Power Supply Circuit: To ensure the stable operation of the main control system, drive system, and peripheral functional modules, a complete multi-stage power supply architecture is designed to achieve stable conversion from AC input to multiple DC power supplies. The power supply section not only provides power to the entire unit but also needs to meet design requirements such as EMC suppression, surge protection, low power consumption, and long-term operational reliability. The power supply circuit of this system mainly consists of three parts: an AC-DC rectifier and filter circuit, a DC-DC isolation step-down circuit, and an LDO linear regulator circuit, which together complete the power conversion, voltage regulation, and system protection functions of the entire unit.

[0079] The first part is the AC-DC rectifier and filter circuit, whose core function is to convert the externally input AC power into stable DC power, providing reliable power supply support for the entire load of the dough mixer. This circuit adopts a combination design of dual magnetic rings and dual X capacitors. The dual magnetic ring inductors are used to suppress common-mode interference in the circuit, while the dual X capacitors are connected in parallel across the two ends of the input circuit to further absorb high-frequency interference signals in the line. This design significantly improves the circuit's EMC test pass rate and effective suppression of electromagnetic interference. This circuit also uses a combination of varistors and thermistors to resist input voltage surges and ensure the safety of the core components of the circuit, building a solid first line of defense for the power supply circuit. The design of the dual NTC thermistor parallel structure effectively reduces the power loss of a single NTC thermistor, significantly reduces the operating temperature rise of the NTC thermistor, and significantly improves the long-term reliability of the circuit. Simultaneously, placing the dual NTC thermistor parallel structure on the AC input side at the front end of the rectifier bridge directly suppresses surge current on the AC input side, preventing surge current from flowing through the rectifier bridge and subsequent filter components, further enhancing the circuit's surge protection capability. Furthermore, this circuit also features multiple discharge resistors connected in parallel at the rear ends of the X capacitor and the large electrolytic capacitor in the filter module. This quickly releases the residual charge stored at the ends of the X capacitor and the large electrolytic capacitor, preventing device damage and electric shock hazards caused by residual charge. It also prevents residual charge from interfering with the surge suppression effect during the next power-on, further improving the circuit's safety and operational stability, making it suitable for the safe use of a dough mixer as a household kitchen appliance.

[0080] The second part is a DC-DC isolated step-down circuit, employing a high-efficiency BUCK architecture design. The selected chips have high integration, and the peripheral components are simplified, effectively optimizing the overall cost and reducing external interference, resulting in a cleaner and more stable output power supply. Simultaneously, the simple circuit structure significantly saves PCB space, adapting to the installation layout requirements of multiple components within the dough mixer, such as the internal motor drive unit, control module, and various detection interfaces. Even in the complex internal space of large devices like dough mixers, flexible placement is possible, reducing the complexity of the overall structural design. Despite its simple structure and small footprint, this circuit can stably output 450mA current, providing ample and convenient power support for external control boards, various detection interfaces, and other peripherals such as cooling fans.

[0081] The third part is the LDO step-down circuit, which, combined with the low-current operating characteristics of its power supply load, adopts a more cost-competitive linear power supply design. This circuit uses an LDO chip as its core and achieves precise power supply through a stepped-down method: the LDO chip stably steps down the voltage output from the auxiliary winding to 5V, providing stable power to the MCU core control unit and various sampling signal circuits, effectively ensuring the stable operation of the core control module for normal instruction output and the signal acquisition module for high-precision data acquisition.

[0082] A working method based on a dough mixer power control and drive integrated system, wherein the working method uses the aforementioned dough mixer power control and drive integrated system, wherein the working method is to control the U3 chip of the main control MCU on the sub-board to cut off the power supply to the motor bus and the power supply to lamp board 1 and lamp board 2, thereby entering a low power consumption mode; when entering the low power consumption mode, the standby power consumption can be reduced to 0.3W; In the motor drive circuit, the main control MCU of the drive board, the pre-drive circuit, and the discrete IGBT three-phase bridge circuit are divided into three parts, which greatly improves the motor debugging and heat dissipation.

[0083] To ensure the safe and smooth operation of the entire machine, a large number of sampling devices are set up, such as IGBT temperature sampling and motor temperature sampling. These devices are responsible for transmitting the temperature of the IGBT three-phase bridge circuit and the motor to the MCU. When the temperature exceeds the MCU's set value, the MCU can quickly stop the motor from working to prevent the machine from crashing or catching fire.

Claims

1. A power control and drive integrated system based on a dough mixer, characterized in that, The system includes a main control board and a sub-board. The main control board provides power to the system and processes logic. The sub-board is connected to the main control board on the left side through a communication interface to realize power distribution and local control. The main control board includes an AC-DC rectifier and filter circuit, a DC-DC step-down circuit, a discrete IGBT three-phase bridge circuit, and a driver board main control MCU. The AC-DC rectifier and filter circuit of the main control board is connected to the DC-DC step-down circuit, the discrete IGBT three-phase bridge circuit, and the bus voltage detection circuit of the main control board, respectively. The discrete IGBT three-phase bridge circuit is connected to the pre-drive circuit and the main control MCU of the driver board, respectively. The DC-DC step-down circuit of the main control board is connected to the pre-drive circuit, the LDO step-down circuit of the main control board, and the cooling fan power supply circuit, respectively. The LDO step-down circuit of the main control board is connected to the serial communication, the main control MCU of the driver board, and the external interface of the main control board, respectively. The main control MCU of the driver board is also connected to the sampling signal. The serial communication is connected to the main control MCU of the sub-board. The main control MCU of the sub-board is connected to the external interface of the sub-board and the LDO step-down circuit of the sub-board. The LDO step-down circuit of the sub-board is connected to the DC-DC step-down circuit of the sub-board. The DC-DC step-down circuit of the sub-board is connected to the AC-DC rectifier and filter circuit of the sub-board. The AC-DC rectifier and filter circuit of the main control board converts AC mains power into DC power as the main power source of the system. The DC-DC step-down circuit of the main control board is input to the LDO voltage regulator circuit to further regulate the voltage and output a stable low-voltage DC power. Direct output control circuit power supply: to power the subsequent control MCU and related circuits; The control signal from the LDO regulator circuit is either the feedback signal output by the LDO or the control command after being regulated by the LDO. External commands from the communication interface, feedback from the right sub-board, or commands from the host computer; After processing the signal, the function outputs a control signal to the DC-DC step-down circuit to adjust the output voltage / current, the backup battery circuit to control the charging / discharging logic, and interacts with the right sub-board through the communication interface.

2. The system according to claim 1, characterized in that, The AC-DC rectifier and filter circuit of the main control board includes a fuse F1. One end of the fuse F1 is connected to terminal 1 of interface CN1. The other end of the fuse F1 is connected to the live wire AC-L, one end of resistor RX1, one end of varistor RV1, one end of safety capacitor CX1, and terminal 2 of boost inductor LL1. Terminal 1 of boost inductor LL1 is connected to one end of safety capacitor CX2, one end of resistor RX4, and terminal 2 of boost inductor LL2. The other end of resistor RX4 is connected to one end of resistor RX6, and the other end of resistor RX6 is connected to one end of resistor RX7. Terminal 1 of boost inductor LL2 is connected to one end of safety capacitor CX3, one end of capacitor CY2, one end of resistor RX3, terminal 1 of thermistor NTC2, and thermistor... The first terminal of NTC1 is connected to the second terminal of NTC2. The other end of resistor RX3 is connected to one end of resistor RX5. The other end of resistor RX5 is connected to one end of resistor RX2. The second terminal of the thermistor NTC2 is connected to the second terminal of the thermistor NTC1 and the second terminal of the bridge circuit. The third terminal of the bridge circuit is connected to the other end of resistor RX2, one end of capacitor CY1, the other end of safety capacitor CX3, and the fourth terminal of boost inductor LL2. The third terminal of boost inductor LL2 is connected to the other end of safety capacitor CX2, the other end of resistor RX7, and the fourth terminal of boost inductor LL1. The third terminal of boost inductor LL1 is connected to the other end of safety capacitor CX1, the other end of varistor RV1, the other end of resistor RX1, the neutral terminal AC-N, and the second terminal of interface CN1. Terminal 1 of the bridge circuit is connected to the positive terminals of output capacitors EC4, EC5, and EC6, one end of capacitor CBB1, one end of resistor R65, one end of capacitor CY3, and the operating voltage 310V. Terminal 4 of the bridge circuit is connected to the negative terminals of output capacitors EC4, EC5, and EC6, the other end of capacitor CBB1, one end of resistor R55, and one end of capacitor CY4, and then grounded. The other ends of resistors R65 and R55 are connected. The other end of capacitor CY2 is connected to the other end of capacitor CY1, terminal 3 of interface CN1, and one end of differential mode inductor LL4, respectively. The other end of capacitor CY3 is connected to the other end of capacitor CY4 and the other end of differential mode inductor LL4, respectively.

3. The system according to claim 1, characterized in that, The GUH terminals of the discrete IGBT three-phase bridge circuit are connected to one end of resistor R72, one end of capacitor C27, one end of resistor R75, and the G terminal of MOSFET Q4 in the pre-drive circuit. The other end of capacitor C27 is connected to the other end of resistor R75, the S terminal of MOSFET Q4, the D terminal of MOSFET Q8, terminal 3 of motor interface L3, terminal 6 of chip U8 in the pre-drive circuit, and one end of capacitor C15 in the pre-drive circuit. The GUL terminals of the discrete IGBT three-phase bridge circuit are connected to one end of resistor R73, one end of capacitor C32, one end of resistor R67, and the G terminal of MOSFET Q8 in the pre-drive circuit. The other end of capacitor C32 is connected to the other end of resistor R67, the S terminal of MOSFET Q8, and one end of resistor R36. The GVH terminals of the discrete IGBT three-phase bridge circuit are respectively connected to one end of resistor R70, one end of capacitor C21, one end of resistor R61, and the G terminal of MOSFET Q6 in the pre-drive circuit. The other end of capacitor C21 is respectively connected to the other end of resistor R61, the S terminal of MOSFET Q6, the D terminal of MOSFET Q9, terminal 2 of motor interface L3, terminal 6 of chip U9 in the pre-drive circuit, and one end of capacitor C16 in the pre-drive circuit. The GVL terminals of the discrete IGBT three-phase bridge circuit are respectively connected to one end of resistor R71, one end of capacitor C31, one end of resistor R66, and the G terminal of MOSFET Q9 in the pre-drive circuit. The other end of capacitor C31 is respectively connected to the other end of resistor R66, the S terminal of MOSFET Q9, and one end of resistor R35. The GWH terminal of the discrete IGBT three-phase bridge circuit is connected to one end of resistor R68, one end of capacitor C22, one end of resistor R74, and the G terminal of MOSFET Q7 in the pre-drive circuit. The other end of capacitor C22 is connected to the other end of resistor R75, the S terminal of MOSFET Q7, the D terminal of MOSFET Q10, terminal 1 of motor interface L3, terminal 6 of chip U10 in the pre-drive circuit, and one end of capacitor C17 in the pre-drive circuit. The GWL terminal of the discrete IGBT three-phase bridge circuit is connected to one end of resistor R69, one end of capacitor C34, one end of resistor R56, and the G terminal of MOSFET Q10 in the pre-drive circuit. The other end of capacitor C34 is connected to the other end of resistor R56, the S terminal of MOSFET Q10, one end of resistor R39, the other end of resistor R36, and the other end of resistor R35. The other end of resistor R39 is grounded. Terminal 4 of the motor interface L3 is connected to one end of capacitor C23 and terminal 1 of the MOTO interface. Terminal 5 of the motor interface L3 is connected to one end of capacitor C20 and terminal 3 of the MOTO interface. Terminal 6 of the motor interface L3 is connected to one end of capacitor C19 and terminal 5 of the MOTO interface. The other end of capacitor C23 is connected to the other ends of capacitor C20 and capacitor C19 and then grounded.

4. The system according to claim 3, characterized in that, The other end of resistor R72 in the pre-drive circuit is connected to terminal 7 of chip U8; the other end of resistor R73 in the pre-drive circuit is connected to terminal 5 of chip U8; the other end of capacitor C15 in the pre-drive circuit is connected to terminal 8 of chip U8; terminal 1 of chip U8 is connected to one end of capacitor C43 and the 15VOUT terminal respectively; the other end of capacitor C43 is grounded; terminal 2 of chip U8 is connected to terminal 3 of the main control MCU of the driver board after series with resistor R22; terminal 3 of chip U8 is connected to terminal 4 of the main control MCU of the driver board after series with resistor R23; terminal 4 of chip U8 is grounded. The other end of resistor R70 in the pre-drive circuit is connected to terminal 7 of chip U9; the other end of resistor R71 in the pre-drive circuit is connected to terminal 5 of chip U9; the other end of capacitor C16 in the pre-drive circuit is connected to terminal 8 of chip U9; terminal 1 of chip U9 is connected to one end of capacitor C33 and the 15VOUT terminal respectively; the other end of capacitor C33 is grounded; terminal 2 of chip U9 is connected to terminal 5 of the main control MCU of the driver board after series connection with resistor R26; terminal 3 of chip U9 is connected to terminal 6 of the main control MCU of the driver board after series connection with resistor R27; and terminal 4 of chip U9 is grounded. The other end of resistor R68 in the pre-drive circuit is connected to terminal 7 of chip U10, the other end of resistor R69 in the pre-drive circuit is connected to terminal 5 of chip U10, and the other end of capacitor C17 in the pre-drive circuit is connected to terminal 8 of chip U10. Terminal 1 of chip U10 is connected to one end of capacitor C11 and the 15VOUT terminal, respectively. The other end of capacitor C11 is grounded. Terminal 2 of chip U10 is connected to terminal 7 of the main control MCU of the driver board after being connected in series with resistor R28. Terminal 3 of chip U10 is connected to terminal 8 of the main control MCU of the driver board after being connected in series with resistor R29. Terminal 4 of chip U10 is grounded.

5. The system according to claim 4, characterized in that, The second terminal of the main control MCU of the driver board is connected to one end of resistor R58, one end of resistor R48, and one end of capacitor C36 of the bus voltage detection circuit. The other end of resistor R58 and capacitor C36 of the bus voltage detection circuit are connected to ground. The other end of resistor R48 is connected to one end of resistor R44 of the bus voltage detection circuit. The other end of resistor R44 is connected to a voltage of +310V. The 9th terminal of the main control MCU of the driver board is connected to one end of resistor R38 and one end of capacitor C24 respectively. The 10th terminal of the main control MCU of the driver board is connected to one end of resistor R32 and the other end of capacitor C24 respectively. The other end of resistor R32 is connected to one end of resistor R39 of the discrete IGBT three-phase bridge circuit. The 11th terminal of the main control MCU of the driver board is connected to one end of resistor R63 and one end of capacitor C26 respectively. The 12th terminal of the main control MCU of the driver board is connected to one end of resistor R64 and the other end of capacitor C26 respectively. The other end of resistor R63 is connected to one end of resistor R39 of the discrete IGBT three-phase bridge circuit. The 13th terminal of the main control MCU of the driver board is connected to one end of resistor R40, one end of the thermistor NTC and one end of capacitor C38 respectively. The other end of resistor R40 is connected to the working voltage 5V, and the other end of the thermistor NTC and the other end of capacitor C38 are connected to ground. The 14th terminal of the main control MCU of the driver board is connected to the 4th terminal of interface CN2, the 15th terminal of the main control MCU of the driver board is connected to the 3rd terminal of interface CN2, the 2nd terminal of interface CN2 is grounded, and the 1st terminal of interface CN2 is connected to the working voltage of 5V. The 16th pin of the main control MCU of the driver board is connected to one end of the resistor R53 of the programming port, and the other end of the resistor R53 is connected to the 2nd pin of the JATG1 interface of the programming port. The 17th pin of the main control MCU of the driver board is connected to one end of the resistor R59 of the programming port, and the other end of the resistor R59 is connected to the 3rd pin of the JATG1 interface of the programming port. The 1st pin of the JATG1 interface is connected to the working voltage of 5V, and the 4th pin of the JATG1 interface is grounded. The 18th terminal of the main control MCU of the driver board is connected to one end of capacitor C30, the 20th terminal of the main control MCU of the driver board is connected to one end of capacitor C29, the 22nd terminal of the main control MCU of the driver board is connected to one end of capacitor C28, and the other end of capacitor C30 is connected to the other end of capacitor C29, the other end of capacitor C28, the 19th terminal of the main control MCU of the driver board, and the 21st terminal of the main control MCU of the driver board and then grounded. The 20th terminal of the main control MCU on the driver board is also connected to the LDO step-down circuit of the main control board. The LDO step-down circuit of the main control board includes a capacitor C12. The positive terminal of the capacitor C12 is connected to one end of the capacitor C14 and the 1st terminal of the chip Z1. The 3rd terminal of the chip Z1 is connected to one end of the capacitor C13, one end of the resistor R50, and one end of the resistor R54. The other end of the capacitor C13 is connected to the 2nd terminal of the chip Z1, the other end of the capacitor C14, and the negative terminal of the capacitor C12 and then grounded. The other end of the resistor R50 is connected to the other end of the resistor R54 and then connected to the DC-DC step-down circuit of the main control board. The 21st pin of the main control MCU of the driver board is also connected to one end of the motor temperature detection resistor R7 and one end of the motor temperature detection capacitor C3. The other end of the motor temperature detection resistor R7 is connected to one end of the motor temperature detection resistor R6 and the 2nd pin of the motor temperature detection interface CN4. The other end of the motor temperature detection capacitor C3 is connected to the 1st pin of the motor temperature detection interface CN4 and then grounded. The other end of the motor temperature detection resistor R6 is connected to the working voltage 5V. The 22nd pin of the main control MCU of the driver board is connected to one end of the resistor R8 of the electromagnetic sensor, the other end of the resistor R8 of the electromagnetic sensor is connected to the 2nd pin of interface CN3, the 1st pin of interface CN3 is connected to the working voltage 5V, and the 3rd pin of interface CN2 is grounded. The 24th terminal of the main control MCU on the driver board is connected to one end of resistor R3 and one end of capacitor C2, respectively. The other end of capacitor C2 is grounded, and the other end of resistor R3 is connected to one end of resistor R39 of the discrete IGBT three-phase bridge circuit.

6. The system according to claim 5, characterized in that, The DC-DC step-down circuit of the main control board includes chip U2. Terminals 5-8 of chip U2 are connected to one end of resistor R2 and the positive terminal of capacitor EC1. The other end of resistor R2 is connected to 310V. The negative terminal of capacitor EC1 is connected to the positive terminal of diode D2, the positive terminal of Zener diode ZD1, one end of resistor R5, the negative terminal of capacitor EC2, and one end of capacitor C1. The negative terminal of diode D2 is connected to terminal 1 and terminal 2 of chip U2 and one end of differential mode inductor L1. The other end of differential mode inductor L1 is connected to the positive terminal of capacitor EC2, the other end of resistor R5, one end of resistor R4, the negative terminal of Zener diode ZD1, the positive terminal of diode D1, and 15V. The negative terminal of diode D1 is connected to terminal 4 of chip U2. The other end of resistor R4 is connected to the other end of capacitor C1 and the 15VOUT terminal.

7. The system according to claim 1, characterized in that, The AC-DC rectifier and filter circuit of the sub-board includes a fuse F2. One end of the fuse F2 is connected to the ACL terminal, and the other end of the fuse F2 is connected to one end of the varistor RV2, one end of the capacitor CX5, one end of the resistor RX8, and terminal 2 of the common mode inductor LL3. The other end of the resistor RX8 is connected to one end of the resistor RX10, and the other end of the resistor RX10 is connected to one end of the resistor RX12. The other end of the resistor RX12 is connected to terminal 3 of the common mode inductor LL3, the other end of the capacitor CX5, the other end of the varistor RV2, and the ACN terminal. Terminal 1 of the common-mode inductor LL3 is connected to one end of resistor R51 of the zero-crossing detection module, terminal 5 of relay K1, one end of resistor CY5, and terminal 1 of the thermistor NTC3. Terminal 6 of relay K1 is connected to terminal 3 of head-up switch CN13. Terminal 1 of head-up switch CN13 is connected to terminal 3 of head-up switch CN6. Terminal 2 of head-up switch CN6 is connected to terminal 3 of relay K1. Terminal 1 of head-up switch CN6 is connected to the other end of resistor CY5, one end of resistor CY6, and the PE terminal. The other end of resistor CY6 is connected to terminal 4 of the common-mode inductor LL3. The circuit consists of: terminal 1 of the circuit, terminal 4 of the relay K1, one end of the capacitor CX4, one end of the resistor RX13, and terminal 3 of the bridge circuit BD2; terminal 2 of the thermistor NTC3, which is connected to the other end of the capacitor CX4, one end of the resistor RX9, and terminal 2 of the bridge circuit BD2; the other end of the resistor RX13, which is connected to one end of the resistor RX11; the other end of the resistor RX11, which is connected to the other end of the resistor RX9; terminal 1 of the bridge circuit BD2, which is connected to one end of the resistor R1 of the LDO step-down circuit on the sub-board and the positive terminal of the capacitor EC3; and terminal 4 of the bridge circuit BD2, which is connected to the negative terminal of the capacitor EC3 and then grounded. Terminal 8 of relay K1 is connected to the anode of diode D3 and the collector of transistor Q1. The emitter of transistor Q1 is connected to one end of resistor R13 and then grounded. The base of transistor Q1 is connected to the other end of resistor R13 and one end of resistor R12. The other end of resistor R12 is connected to terminal 4 of the main control MCU on the sub-board. Terminal 1 of relay K1 is connected to the 5V operating voltage and the cathode of diode D3.

8. The system according to claim 1, characterized in that, The other end of resistor R51 in the zero-crossing detection module is connected to one end of resistor R52. The other end of resistor R52 is connected to one end of resistor R49. The other end of resistor R49 is connected to one end of resistor R60, one end of capacitor C35, and the B terminal of transistor Q3. The C terminal of transistor is connected to one end of resistor R47 and one end of resistor R46. The other end of resistor R46 is connected to the 5V operating voltage. The E terminal of transistor is connected to the other end of resistor R60, the other end of capacitor C35, and one end of capacitor C25 and then grounded. The other end of resistor R47 is connected to the other end of capacitor C25 and the 28th terminal of the main control MCU on the sub-board. The main control MCU of the sub-board is connected to terminal 6 of the serial communication light board 1, terminal 20 of the main control MCU of the sub-board is connected to the serial communication light board 1, and terminal 21 of the main control MCU of the sub-board is connected to the serial communication light board 1. The 9th terminal of the main control MCU of the sub-board is connected to the LED board 2 for serial communication, the 10th terminal of the main control MCU of the sub-board is connected to the LED board 2 for serial communication, and the 15th terminal of the main control MCU of the sub-board is connected to the LED board 2 for serial communication. The main control MCU of the sub-board is connected to a potentiometer at pin 11; the main control MCU of the sub-board is connected to a Hall switch at pin 16; the main control MCU of the sub-board is connected to a power switch at pin 17; the main control MCU of the sub-board is connected to a programming port at pin 25; and the main control MCU of the sub-board is also connected to a programming port at pin 26. The 25th pin of the main control MCU on the secondary board is also connected to the serial communication optical isolation device, and the 26th pin of the main control MCU on the secondary board is also connected to the serial communication optical isolation device.

9. The system according to claim 8, characterized in that, The serial communication optocoupler isolation is connected to the serial communication of the electrode plate.

10. A working method based on an integrated power control and drive system for a dough mixer, characterized in that, The working method uses an integrated power control and drive system for a dough mixer as described in any one of claims 1-9. The working method is as follows: the main control MCU U3 chip on the sub-board controls the cutting off of the motor bus voltage power supply and the cutting off of the power supply to lamp board 1 and lamp board 2 to enter a low power mode; when entering the low power mode, the standby power consumption can be reduced to 0.3W. In the motor drive circuit, the main control MCU of the drive board, the pre-drive circuit, and the discrete IGBT three-phase bridge circuit are divided into three parts, which greatly improves the motor debugging and heat dissipation.

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