A DC brushless motor drive circuit

Abstract

The present invention discloses a DC brushless motor drive circuit, including a motor state detection module, a monitoring module, a control module and a drive module. The motor state detection module is used to detect the current state of the DC brushless motor; the monitoring module is connected to the motor state detection module, and is used to receive the current state of the DC brushless motor and / or an external signal, and output a corresponding execution command according to the current state of the DC brushless motor and / or the external signal; the control module is connected to the monitoring module, and is used to receive and process the execution command, and generate a corresponding control signal; the drive module is connected to the control module, and is used to output a drive signal to the DC brushless motor according to the control signal, so that the DC brushless motor performs a corresponding action. The present invention replaces the software control scheme in the existing controller, and selects a hardware scheme in which the monitoring module and the hardware decoding chip jointly drive the DC brushless motor, bypassing the existing software control loopholes and solving the jamming problem in the application scenario.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and in particular to a direct current brushless motor drive circuit. Background Art

[0002] Fitness mirror is a new type of lightweight fitness equipment. Figure 1 As shown, it specifically includes a mirror module 1, a display 2 and a strength training mechanism 3. Specifically, the display 2 is arranged behind the mirror module 1, and the mirror module 1 can superimpose and display the reflected motion posture image of the user and the video content played by the display 2 thereon, and the strength training mechanism 3 includes a controller, a DC brushless motor, a winding drum and a tension steel cable 31, the output shaft of the DC brushless motor is connected to the winding drum, and the fixed end of the tension steel cable 31 is arranged on the winding drum. When the motor is running, the motor drives the winding drum to roll, thereby applying motion resistance to the tension steel cable 31, and the user stretches the free end of the tension steel cable 31 to perform strength training. Its working principle is: in the starting stage, when the force applied by the user to the tension cable 31 is greater than the motion resistance, the tension ring can be pulled; in the stable stage, when the force applied by the user to the tension cable 31 is less than the motion resistance, for example, the user relaxes the tension cable 31, since the DC brushless motor continues to output motion resistance to the tension cable 31, the tension cable 31 will retract until the user applies a force greater than the motion resistance again, and the tension cable 31 will be pulled out, and so on, so that the user can continue to exercise.

[0003] In existing fitness mirror products, the controller usually uses an STM32 microcontroller, and the STM32 microcontroller directly uses software to control the DC brushless motor. The advantage is that the circuit structure is simple, but the inventor found in the research that the defects and instability in the software will be directly reflected in the movement of the DC brushless motor, that is, the STM32 microcontroller directly performs FOC soft decoding and directly outputs. From the output results, the DC brushless motor has obvious output jamming (phase control error) during the process of stalling and reversing. No matter how the program is programmed or the software is modified, the jamming problem will still occur. Summary of the invention

[0004] The present invention aims to provide a brushless DC motor drive circuit to solve the problem that STM32 directly performs FOC soft decoding, resulting in obvious output jamming (phase control error) of the brushless DC motor during the process of stalling and reversing.

[0005] To achieve the above object, an embodiment of the present invention provides a brushless DC motor drive circuit, comprising:

[0006] The motor status detection module is used to detect the current status of the brushless DC motor;

[0007] A monitoring module, connected to the motor state detection module, for receiving the current state of the brushless DC motor and / or an external signal, and outputting a corresponding execution command according to the current state of the brushless DC motor and / or the external signal;

[0008] A control module, connected to the monitoring module, configured to receive and process the execution command and generate a corresponding control signal;

[0009] The driving module is connected to the control module and is used to output a driving signal to the brushless DC motor according to the control signal, so that the brushless DC motor performs a corresponding action.

[0010] In one embodiment, a half-bridge driving chip is further included, the control module is connected to the half-bridge driving chip, the half-bridge driving chip is connected to the driving module, and the control signal output by the control module is input to the driving module through the half-bridge driving chip, so that the driving module drives the brushless DC motor to perform corresponding actions.

[0011] In a certain embodiment, it further includes a PWM generating module, the monitoring module is connected to the PWM generating module, and the PWM generating module is connected to the driving module and is used to generate a PWM signal to the driving module.

[0012] In a certain embodiment, the half-bridge drive chip includes a FAN7888 chip; the PWM generation module includes a field effect transistor, the ENPWM end of the field effect transistor is connected to the PWM end of the monitoring module, the control end of the field effect transistor is connected to the power supply, and the output end of the field effect transistor is connected to the control end of the drive module.

[0013] In one embodiment, the control module includes a control chip of model MC33035.

[0014] In one embodiment, the monitoring module includes a Raspberry Pi or an STM32 microcontroller.

[0015] In one embodiment, the Raspberry Pi includes a Pyco control chip.

[0016] In a certain embodiment, the motor state detection module includes a Hall sensing circuit, and the Hall sensing circuit is used to detect the rotor position of the brushless DC motor;

[0017] The driving module includes a plurality of field effect transistors, and the plurality of field effect transistors are respectively used to output driving signals to the brushless DC motor.

[0018] In a certain embodiment, the monitoring module is further used to calculate the real-time power and the total output power of the brushless DC motor according to the current state of the brushless DC motor.

[0019] In one embodiment, it further includes a power supply interface and a voltage conversion module, and the motor state detection module, the monitoring module, the control module and the drive module are connected to the power supply through the voltage conversion module and the power supply interface respectively.

[0020] Compared with the existing controller that controls the brushless DC motor through software, which causes the brushless DC motor to freeze when repeatedly overloaded in reverse, the brushless DC motor drive circuit of the embodiment of the present invention uses a monitoring module and a hardware decoding chip (control module) to jointly drive the brushless DC motor to replace the software control solution in the existing controller, bypassing the existing software control loopholes and solving the freezing problem in the application scenario. Specifically, the embodiment of the present invention classifies the motion logic of the brushless DC motor into the monitoring module for processing, which is simple and transparent to program and consumes little computing power. The control module is used as the execution chip, and the execution command of the monitoring module is analyzed by hardware to improve the stability of the brushless DC motor output, avoid the freezing problem caused by repeated reverse overload of the brushless DC motor, and improve the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a structural schematic diagram of a fitness mirror in the prior art;

[0023] Figure 2 is a structural schematic diagram of a brushless DC motor drive circuit provided by an embodiment of the present invention;

[0024] Figure 3 is a structural schematic diagram of a brushless DC motor drive circuit provided by another embodiment of the present invention;

[0025] Figure 4 It is a structural diagram of a brushless DC motor position feedback interface provided by a certain embodiment of the present invention;

[0026] Figure 5 It is a schematic diagram of a power interface and a voltage conversion circuit provided by a certain embodiment of the present invention;

[0027] Figure 6 It is a circuit diagram of a FAN7888 control chip provided by an embodiment of the present invention;

[0028] Figure 7 is a circuit diagram of a PWM generation module provided by a certain embodiment of the present invention;

[0029] Figure 8 is a circuit diagram of a driving module provided by an embodiment of the present invention;

[0030] Fig. 9 It is a circuit diagram of the MC33035 control chip provided by a certain embodiment of the present invention;

[0031] Fig.10 is a circuit diagram of a Pyco control chip provided by an embodiment of the present invention;

[0032] Fig.11 The diagram is a circuit diagram of a brushless DC motor provided in one embodiment of the present invention.

[0033] Description of the main components and symbols of the present invention:

[0034] 100. DC brushless motor drive circuit; 10. Motor state detection module; 11. Hall sensing circuit; 20. Monitoring module; 30. Control module; 40. Drive module; 50. Half-bridge drive chip; 60. PWM generation module; 200. DC brushless motor; 300. Other data acquisition modules. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be understood that the step numbers used in this article are only for the convenience of description and are not intended to limit the order in which the steps are executed.

[0037] It should be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0038] The terms “include” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0039] The term "and / or" means and includes any and all possible combinations of one or more of the associated listed items.

[0040] The embodiment of the present invention provides a DC brushless motor drive circuit 100, which can be applied to any product that needs to use a DC brushless motor 200, such as an electric bicycle, a fitness mirror, etc. The present invention is described in detail using a fitness mirror as an example. Figure 1 Taking the fitness mirror product as an example, the brushless DC motor 200 mainly provides the user with preset motion resistance for the user's strength training. If the existing controller STM32 microcontroller is used, it is easy to cause the user to be stuck due to reverse overload output when performing strength training with a constant large torque, which seriously affects the user's precise strength training and the user experience is poor.

[0041] To do this, see Figure 2 The brushless DC motor driving circuit 100 of the embodiment of the present invention includes: a motor state detection module 10 , a monitoring module 20 , a control module 30 and a driving module 40 .

[0042] The motor state detection module 10 is used to detect the current state of the brushless DC motor 200;

[0043] The monitoring module 20 is connected to the motor state detection module 10, and is used to receive the current state of the brushless DC motor 200 and / or an external signal, and output a corresponding execution command according to the current state of the brushless DC motor 200 and / or the external signal;

[0044] The control module 30 is connected to the monitoring module 20 and is used to receive and process execution commands and generate corresponding control signals;

[0045] The driving module 40 is connected to the control module 30 and is used for outputting a driving signal to the DC brushless motor 200 according to the control signal, so that the DC brushless motor 200 performs a corresponding action.

[0046] In the embodiment of the present invention, the motor state detection module 10 is connected to the monitoring module 20, the monitoring module 20 is connected to the control module 30, and the control module 30 is connected to the driving module 40. The motor state detection module 10 detects the current state of the brushless DC motor 200 and sends the state to the monitoring module 20. The monitoring module 20 receives the current state of the brushless DC motor 200, or receives an external signal, or receives both at the same time, and outputs the execution command to be executed by the corresponding brushless DC motor 200 according to the internal preset algorithm.

[0047] Among them, the state of the brushless DC motor 200 includes the current position of the rotor, speed, stall state, etc., and the corresponding execution commands include forward and reverse control, speed adjustment, start and stop control, etc. The external signals include some auxiliary signals for use of the brushless DC motor 200 applied to the product, user motion signals, expected control signals, etc.

[0048] In one embodiment, the monitoring module 20 is also used to connect with other data acquisition modules 300 , and the other data acquisition modules 300 generate external signals and send the external signals to the monitoring module 20 .

[0049] Please combine Figure 1 Taking the fitness mirror product as an example, the DC brushless motor 200 mainly provides the user with a preset motion resistance for the user to perform strength training, and the external signal includes the use of auxiliary signals, user physiological state data, training setting parameters, etc. Through the human body detection function of the fitness mirror, it can be determined whether the user is using the fitness mirror. If there is a user, the current use signal is sent to the monitoring module 20, so that the monitoring module 20 outputs a command to control the operation of the DC brushless motor 200 according to the current use signal and the state of the DC brushless motor 200. Through the physiological state data input and acquisition function of the fitness mirror, the user's physiological state data is obtained, so that the monitoring module 20 generates a corresponding execution command for the DC brushless motor 200 according to the internal preset algorithm.

[0050] In one embodiment, the monitoring module 20 is further configured to calculate the real-time power and the total output power of the brushless DC motor 200 according to the current state of the brushless DC motor 200 .

[0051] By acquiring the real-time power and total output power of the brushless DC motor 200 , in addition to understanding the operating parameters of the brushless DC motor 200 , other data can be further obtained based on the real-time power and total output power for different products.

[0052] Taking the fitness mirror as an example, the pulling stroke of the tension cable 31 corresponding to a stretching exercise can be accurately calculated according to the real-time power of the brushless DC motor 200, and the calories consumed by the user in the stretching exercise can be calculated. In addition, the pulling stroke of the tension cable 31 corresponding to a whole set of strength training can be accurately calculated according to the total output power consumed by the brushless DC motor 200, and the calories consumed by the user in the whole set of strength training can be calculated as a reference for the user's exercise.

[0053] It should be noted that how the monitoring module 20 outputs the corresponding execution command according to the current state of the brushless DC motor 200 and / or the external signal is programmed accordingly according to the specific product. The present invention does not limit the algorithm stored in the monitoring module 20 after the monitoring module 20 is specifically programmed.

[0054] In summary, compared with the existing controller that controls the brushless DC motor 200 through software, which causes the brushless DC motor 200 to freeze when repeatedly overloaded in reverse, the embodiment of the present invention uses a hardware solution that uses the monitoring module 20 and the hardware decoding chip (control module 30) to drive the brushless DC motor 200 to replace the software control solution in the existing controller, bypassing the existing software control loopholes and solving the freeze problem in the application scenario. Specifically, the embodiment of the present invention assigns the motion logic of the brushless DC motor 200 to the monitoring module 20 for processing, which is simple and transparent in programming and consumes little computing power. The control module 30 is used as the execution chip, and the execution command of the hardware parsing monitoring module 20 can improve the stability of the output of the brushless DC motor 200, avoid the freeze problem caused by repeated reverse overload of the brushless DC motor 200, and improve the user experience.

[0055] See also Figure 3 In one embodiment, the motor state detection module 10 includes a Hall sensing circuit 11 , and the Hall sensing circuit 11 is used to detect the rotor position of the brushless DC motor 200 .

[0056] like Figure 4 As shown, the Hall sensor circuit 11 detects the rotor position of the brushless DC motor 200 , and the detection result is fed back to the monitoring module 20 through the SC, SB, and SA terminals.

[0057] See also Figure 5 In one embodiment, the brushless DC motor driving circuit 100 further includes a power supply interface and a voltage conversion module, and the motor state detection module 10, the monitoring module 20, the control module 30 and the driving module 40 are respectively connected to the power supply through the voltage conversion module and the power supply interface.

[0058] In an embodiment of the present invention, Figure 5 (a) is a power interface circuit diagram in a certain embodiment, Figure 5 (b) and 5(c) are respectively a 12V to 5V circuit diagram and a 12V to 3.3V circuit diagram in a certain embodiment. The power supply is inserted into the power interface, and the voltage conversion module converts the high voltage into a voltage suitable for electronic components, such as converting the 12V voltage into a 5V or 3.3V voltage, so as to power the electronic components such as the motor state detection module 10, the monitoring module 20, the control module 30 and the drive module 40.

[0059] See also Figure 3In a certain embodiment, the DC brushless motor driving circuit 100 also includes a half-bridge driving chip 50, the control module 30 is connected to the half-bridge driving chip 50, and the half-bridge driving chip 50 is connected to the driving module 40. The control signal output by the control module 30 is input to the driving module 40 through the half-bridge driving chip 50, so that the driving module 40 drives the DC brushless motor 200 to perform corresponding actions.

[0060] In the embodiment of the present invention, the function of the half-bridge driver chip 50 is mainly to generate an AC trigger signal through a power tube, thereby generating a large current to further drive the DC brushless motor 200. The difference between the half-bridge driver and the single-chip microcomputer driver is that the single-chip microcomputer has limited driving capability and is generally only used as a driving signal.

[0061] See also Figure 3 In one embodiment, the brushless DC motor driving circuit 100 further includes a PWM generating module 60 , the monitoring module 20 is connected to the PWM generating module 60 , and the PWM generating module 60 is connected to the driving module 40 and is used to generate a PWM signal to the driving module 40 .

[0062] In the embodiment of the present invention, the PWM generation module 60 is used to adjust the excitation current of the brushless DC motor 200, so that the torque output of the brushless DC motor 200 can be adjusted to achieve the purpose of precise control.

[0063] Specifically, the monitoring module 20 collects the current real-time rotational speed of the brushless DC motor 200, and compares the real-time rotational speed of the brushless DC motor 200 with the preset rotational speed (i.e., the expected rotational speed). When the real-time rotational speed of the brushless DC motor 200 is different from the preset rotational speed, the monitoring module 20 performs calculations through a closed-loop PID algorithm (i.e., a preset closed-loop control adjustment algorithm), and then generates a PWM signal through the PWM generation module 60, and sends it to the drive module 40. The drive module 40 adjusts the rotational speed of the brushless DC motor 200 according to the PWM signal, thereby achieving the purpose of accurately maintaining the speed of the brushless DC motor 200 at the preset rotational speed, thereby achieving the purpose of accurately rotating the brushless DC motor 200 at a constant speed.

[0064] See also Figure 6 and Figure 7 In one embodiment, the half-bridge driver chip 50 includes a control chip of model FAN7888. The PWM generation module 60 includes a field effect transistor QPower (Field Effect Transistor, FET), the ENPWM terminal of the field effect transistor QPower is connected to the PWM terminal of the monitoring module 20, the control terminal of the field effect transistor QPower is connected to the power supply, and the output terminal of the field effect transistor QPower is connected to the control terminal of the driver module 40.

[0065] like Figure 6 As shown, the FAN7888 control chip is a chip that integrates three half-bridge gate driver integrated circuits. It is designed for high-voltage, high-speed driving MOSFET and IGBT and can operate at a voltage of up to +200V.

[0066] like Figure 7 As shown, the field effect transistor Q of the PWM generation module 60 Power It is a chip outside the control module 30 for adjusting the excitation current of the brushless DC motor 200, and specifically includes three pins, namely, an ENPWM terminal 1, a control terminal 2 and an output terminal 3.

[0067] Specifically, the ENPWM terminal 1 of the field effect transistor QPower is connected to the PWM terminal of the monitoring module 20 , the control terminal 2 is connected to the high level output terminal (such as the +200V output terminal), and the output terminal 3 is connected to the control terminal of the driving module 40 .

[0068] See also Figure 8 In a specific embodiment, the driving module 40 includes a plurality of field effect transistors, and the plurality of field effect transistors are respectively used to output driving signals to the brushless DC motor 200 .

[0069] like Figure 8 As shown, the driving module 40 includes 6 field effect transistors Q1-6, and the 6 field effect transistors Q1-6 are used to directly output high voltage to the DC brushless motor 200. Each field effect transistor includes three pins, namely an input terminal 1, a control terminal 2 and an output terminal 3.

[0070] Specifically, field effect transistors Q1-3 output three high-end drive signals, and field effect transistors Q4-6 output three low-end drive signals. By adjusting the frequencies and pulse widths of the six drive signals, the voltage-frequency ratio can be adjusted to adjust the speed of the brushless DC motor 200.

[0071] The input terminals 1 of the field effect transistors Q1-3 are connected to the HO1, HO2, and HO3 terminals of the half-bridge driver chip 50, respectively, and the control terminals 2 of the field effect transistors Q1-3 are connected to the HO1, HO2, and HO3 terminals of the half-bridge driver chip 50, respectively. Power The output terminal 3 of the field effect transistor Q1-3 is connected to the three high-level input terminals of the DC brushless motor 200. The input terminal 1 of the field effect transistor Q4-6 is connected to the LO1, LO2, and LO3 terminals of the half-bridge driver chip 50, the control terminal 2 of the field effect transistor Q4-6 is connected to the three low-level input terminals of the DC brushless motor 200, and the output terminal 3 of the field effect transistor Q4-6 is grounded.

[0072] See also Fig. 9In one embodiment, the control module 30 includes a control chip of model MC33035.

[0073] The MC33035 control chip is a highly integrated electronic chip. The control system of the three-phase brushless DC motor based on it has the advantages of simple circuit, strong anti-interference, high reliability and good stability.

[0074] Its main components include rotor position sensor decoder circuit, internal reference power supply with temperature compensation, frequency-adjustable sawtooth oscillator, error amplifier, pulse width modulation (PWM) comparator, output drive circuit, undervoltage lockout protection, chip overheat protection and other fault outputs and current limiting circuits.

[0075] In the embodiment of the present invention, the MC33035 control chip can control the forward and reverse rotation, braking, and start and stop control of the brushless DC motor 200 .

[0076] The pin arrangement of the MC33035 control chip is as follows Fig. 9 As shown, the function definition of each pin is shown in Table 1.

[0077] Table 1

[0078]

[0079]

[0080]

[0081] The working principle of the MC33035 control chip is as follows: after the monitoring module 20 outputs corresponding execution commands (such as forward and reverse commands, braking commands, start and stop commands, etc. of the DC brushless motor 200) according to the current state of the DC brushless motor 200 and / or external signals, the MC33035 control chip performs logical analysis on the execution commands and outputs corresponding control commands to the drive module 40, so that the DC brushless motor 200 performs corresponding actions.

[0082] Specifically, when the monitoring module 20 outputs a forward / reverse command, the forward / reverse output of the MC33035 control chip can change the direction of the DC brushless motor 200 by flipping the voltage on the stator winding: when the input state changes, the specified sensor input code will change from a high level to a low level, thereby changing the rectification timing to cause the DC brushless motor 200 to change its rotation direction.

[0083] When the monitoring module 20 outputs a start / stop command, the on / off control of the brushless DC motor 200 can be realized by the output enable of the MC33035 control chip. When the OUT EN pin of the MC33035 control chip is open, the built-in pull-up resistor connected to the positive power supply will start the top drive (Output Enable) output and the bottom drive (Vc) output timing. When the OUT EN pin of the MC33035 control chip is grounded, the top drive output (Output Enable) will be turned off and the bottom drive (Vc) will be forced to be low, thereby stopping the brushless DC motor 200.

[0084] In one embodiment, the monitoring module 20 includes a Raspberry Pi or an STM32 microcontroller.

[0085] Raspberry Pi is an ARM-based microcomputer motherboard that uses an SD / MicroSD card as its memory hard drive. There are 1 / 2 / 4 USB ports and a 10 / 100 Ethernet port (Type A does not have a network port) around the card motherboard. It has many GPIO ports and has all the basic functions of a PC. It is small in size and easy to program.

[0086] As a commonly used single-chip microcomputer, STM32 single-chip microcomputer has the advantages of high performance, real-time performance, digital signal processing, low power consumption and low voltage, while maintaining high integration and easy development.

[0087] See also Fig.10 In one embodiment, the Raspberry Pi includes a Pyco control chip.

[0088] The PYCO control chip is a single-chip microcomputer that can be directly programmed with Python. It is an extension of the Raspberry Pi. The programming is simple and transparent, and the computing power consumption is small.

[0089] In the embodiment of the present invention, the main components of the Pyco control chip include a rotor position sensor decoder circuit, a pulse width modulation (PWM) comparator and an output drive circuit.

[0090] The Pyco control chip is mainly used to output the execution commands that the corresponding DC brushless motor 200 needs to execute according to the current state of the DC brushless motor 200 and / or receive external signals, according to the internal preset algorithm, such as controlling the forward and reverse rotation, braking, start and stop of the DC brushless motor 200.

[0091] The pin arrangement of the Pyco control chip is as follows Fig.10 As shown, the function definition of each pin is shown in Table 2.

[0092] Table 2

[0093]

[0094] The working principle of the Pyco control chip is as follows: the rotor position signal input output by the motor state detection module 10 is received through the three sensor input terminals SC, SB, and SA, and then the execution command is sent to the MC33035 control chip according to the internal preset algorithm requirements. The MC33035 control chip is used to logically analyze the relevant commands and output the driving logic to the half-bridge drive chip 50. The half-bridge drive chip 50 will generate an AC trigger signal through the power tube, thereby generating a large current to the drive module 40. The drive module 40 outputs a large current to the DC brushless motor 200, so that the DC brushless motor 200 performs the corresponding action. At the same time, the Pyco control chip also generates a PWM signal through the PWM generation module 60 and sends it to the drive module 40. The drive module 40 adjusts the speed of the DC brushless motor 200 according to the PWM signal, so as to achieve the speed of the DC brushless motor 200 to be kept at the preset speed, so as to achieve the purpose of making the DC brushless motor 200 rotate at a constant speed.

[0095] To better understand the DC brushless motor drive circuit 100 of the present invention, please refer to Figure 2-11 Now, the working principle of the brushless DC motor driving circuit 100 is described with reference to a specific embodiment.

[0096] The Pyco control chip receives the rotor position signal input output by the motor state detection module 10 through the three sensor input terminals SC, SB, and SA, and then sends the execution command to the MC33035 control chip through the Tx terminal according to the internal preset algorithm. The MC33035 control chip is used to logically parse the relevant commands, and output the driving logic to the BT, AT, and CT terminals of the FAN7888 control chip through the three open-collector top drive output terminals BT, AT, and CT. The FAN7888 control chip will generate an AC trigger signal through the power tube, which is input to the input terminal 1 of the field effect transistor Q1-3 through the HO1 terminal, HO2 terminal, and HO3 terminal, and is input to the input terminal 1 of the field effect transistor Q4-6 through the LO1 terminal, LO2 terminal, and LO3 terminal. One group of VS1, VS2, and VS3 terminals of the DC brushless motor 200 respectively receives the driving signal output by the output terminal 3 of the field effect transistor Q1-3, and another group of VS1, VS2, and VS3 terminals of the DC brushless motor 200 respectively receives the driving signal output by the output terminal 3 of the field effect transistor Q1-6, so that the DC brushless motor 200 performs corresponding actions.

[0097] At the same time, the Pyco control chip also operates through a closed-loop PID algorithm (i.e., a preset closed-loop control adjustment algorithm) to input the command for adjusting the speed of the brushless DC motor 200 through its PWM terminal to the field effect transistor Q Power ENPWM terminal 1, field effect transistor Q PowerThe PWM signal is input to the control terminals of the field effect transistors Q1 - 3 through the output terminal 3 , thereby adjusting the speed of the brushless DC motor 200 .

[0098] Therefore, compared with the existing controller that controls the brushless DC motor 200 through software, which causes the brushless DC motor 200 to freeze when repeatedly overloaded in reverse, the embodiment of the present invention uses a hardware solution that uses a Pyco control chip and a hardware decoding chip (MC33035 control chip) to drive the brushless DC motor 200 to replace the software control solution in the existing controller, bypassing the existing algorithm control loopholes and solving the freeze problem in the application scenario. Specifically, the embodiment of the present invention assigns the motion logic of the brushless DC motor 200 to the Pyco control chip for processing, which is simple and transparent to program and consumes little computing power. The MC33035 control chip is used as the execution chip. The hardware parsing of the execution command of the Pyco control chip can improve the stability of the output of the brushless DC motor 200, avoid the freeze problem caused by repeated reverse overload of the brushless DC motor 200, and improve the user experience.

[0099] The above are preferred embodiments of the present invention. It should be noted that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A brushless DC motor drive circuit, used in a fitness mirror, characterized in that: It includes a motor status detection module, a monitoring module, a control module and a drive module connected in series in sequence: The motor status detection module is used to detect the current status of the brushless DC motor; A monitoring module, connected to the motor state detection module, for receiving the current state of the brushless DC motor and / or an external signal, and outputting a corresponding execution command according to the current state of the brushless DC motor and / or the external signal based on an internal preset algorithm; The external signal includes auxiliary signals and user physiological status data, and the execution command includes forward and reverse control, speed control, start and stop control, etc.; The monitoring module is also used to calculate the real-time power and total output power of the brushless DC motor according to the current state of the brushless DC motor; The monitoring module includes a Raspberry Pi or an STM32 microcontroller; A control module, connected to the monitoring module, for receiving and processing the execution command and generating a corresponding control signal, wherein the control module includes a control chip of model MC33035; The monitoring module and the control module jointly drive the brushless DC motor; wherein the motion logic of the brushless DC motor is processed by the monitoring module and outputs an execution command, and the control module acts as an execution chip to perform hardware analysis on the execution command output by the monitoring module; The driving module is connected to the control module and is used to output a driving signal to the brushless DC motor according to the control signal, so that the brushless DC motor performs a corresponding action.

2. The brushless DC motor drive circuit according to claim 1, characterized in that: It also includes a half-bridge drive chip, the control module is connected to the half-bridge drive chip, the half-bridge drive chip is connected to the drive module, and the control signal output by the control module is input to the drive module through the half-bridge drive chip, so that the drive module drives the DC brushless motor to perform corresponding actions.

3. The brushless DC motor drive circuit according to claim 2, characterized in that: It also includes a PWM generating module, the monitoring module is connected to the PWM generating module, and the PWM generating module is connected to the driving module and is used to generate a PWM signal to the driving module.

4. The brushless DC motor drive circuit according to claim 3, characterized in that: The half-bridge driving chip includes a FAN7888 chip; the PWM generating module includes a field effect transistor, the ENPWM terminal of the field effect transistor is connected to the PWM terminal of the monitoring module, the control terminal of the field effect transistor is connected to a power supply, and the output terminal of the field effect transistor is connected to the control terminal of the driving module.

5. The brushless DC motor drive circuit according to claim 1, characterized in that: The Raspberry Pi includes a Pyco control chip.

6. The brushless DC motor drive circuit according to any one of claims 1 to 5, characterized in that: The motor state detection module includes a Hall sensing circuit, and the Hall sensing circuit is used to detect the rotor position of the brushless DC motor; The driving module includes a plurality of field effect transistors, and the plurality of field effect transistors are respectively used to output driving signals to the brushless DC motor.

7. The brushless DC motor drive circuit according to any one of claims 1 to 5, characterized in that: It also includes a power supply interface and a voltage conversion module, and the motor state detection module, the monitoring module, the control module and the drive module are connected to the power supply through the voltage conversion module and the power supply interface respectively.

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