Single-chip motor driving system

Abstract

The utility model relates to the technical field of motor control, in particular to a single-chip motor driving system, which comprises a power supply module, a singlechip module, a pre-driving module and a three-phase bridge module, and is characterized in that the pre-driving module is used for converting a singlechip logic level into a mosfet driving signal and then sending the mosfet driving signal to the three-phase bridge module; the single-chip microcomputer module comprises a processor CPU, an incremental encoder module, a HALL input module, an AD peripheral and a digital IO. The incremental encoder module, the HALL input module, the AD peripheral and the digital IO are connected with the processor CPU through a data bus. Compared with the prior art, the single-chip motor driving system is high in integration level, can meet the requirements of small-size products, and is good in expansibility.

Description

[Technical field]

[0001] The utility model relates to the technical field of motor control, in particular to a single-chip motor drive system. [Background technology]

[0002] At present, the motor drive system is mainly realized by the following methods:

[0003] 1. Implement the algorithm in pure software based on single chip microcomputer or DSP, with external power supply module, pre-drive module and three-phase bridge module. This drive system has many discrete components, which not only makes the system cost high, but also has the disadvantages of low reliability and the driver board cannot be made small;

[0004] Second, the control algorithm is implemented based on pure hardware, and the power module, pre-driver module, and three-phase bridge module are integrated. Patent CN214480350U discloses a single-chip integrated brushless DC motor drive control system, but this motor drive system is highly integrated and the program is fixed, so it is only suitable for special occasions and cannot meet the application requirements of most users' customized functions.

[0005] 3. Implement the control algorithm based on pure hardware, and integrate the power module, pre-drive module, and 8-bit single-chip microcomputer module. Patent CN204696971U discloses a single-chip solution of this method. This solution integrates the FOC algorithm and can be used for application layer design through an 8-bit single-chip microcomputer. This solution is only for FOC applications and does not integrate a three-phase bridge circuit.

[0006] 4. Based on the integrated 32-bit MCU and motor vector control algorithm module, there is no power module, pre-drive module, or three-phase bridge circuit, and external discrete components are required to implement the entire system.

[0007] The existing single-chip microcomputers for motor control are all equipped with motor drive peripherals. Some commonly used algorithms such as Clark, Park, PI controller, and low-pass filter can be implemented through software. Moreover, after the main frequency is increased, the real-time performance is also met, but these all require external discrete components to realize the motor drive function. For some products with limited volume that need to be integrated into the tail end of the motor, this cannot be achieved. [Contents of the utility model]

[0008] In order to overcome the above problems, the utility model proposes a single-chip motor drive system that can effectively solve the above problems.

[0009] The utility model provides a technical solution to solve the above technical problems: a single-chip motor drive system is provided, comprising a power supply module, a single-chip microcomputer module, a pre-drive module and a three-phase bridge module, wherein the pre-drive module is connected to the single-chip microcomputer module, the three-phase bridge module is connected to the pre-drive module, the three-phase bridge module is connected to the motor, and the power supply module is respectively connected to the single-chip microcomputer module, the pre-drive module and the three-phase bridge module; the power supply module is used to provide power to the single-chip microcomputer module, the pre-drive module and the three-phase bridge module; the pre-drive module is used to convert the single-chip microcomputer logic level into a mosfet drive signal, and then send the mosfet drive signal to the three-phase bridge module; the single-chip microcomputer module comprises a processor CPU, an incremental encoder module, a HALL input module, an AD peripheral and a digital IO, and the incremental encoder module, the HALL input module, the AD peripheral and the digital IO are connected to the processor CPU through a data bus.

[0010] Preferably, the single chip microcomputer module comprises a communication module, an operational amplifier module, a comparator module RAM and a ROM, and the communication module, the operational amplifier module, the comparator module RAM and the ROM are connected to the processor CPU via a data bus.

[0011] Preferably, the single chip microcomputer module comprises a timer counter module and a clock module, and the timer counter and the clock module are respectively connected to the processor CPU.

[0012] Preferably, the single chip microcomputer module includes a Hall input module, and the Hall input module is connected to a processor CPU.

[0013] Preferably, the three-phase bridge module is composed of three NMOSFETs and three PMOSFETs, and is used to receive a pre-drive signal, output a high-voltage signal, and realize three-phase drive of the motor and operation of the motor.

[0014] Compared with the prior art, the single-chip motor drive system of the utility model solves the shortcoming of poor scalability of the existing motor drive integrated chip; it has high integration, can meet the demand for small-volume products, and has good scalability.

Brief Description of the Drawings

[0015] Figure 1 This is a framework diagram of the single-chip motor drive system of the utility model;

[0016] Figure 2 This is a framework diagram of a single-chip microcomputer module of a single-chip motor drive system of the utility model;

[0017] Figure 3 This is a framework diagram of a pre-drive module of a single-chip motor drive system of the utility model;

[0018] Figure 4It is a framework diagram of a three-phase bridge module of a single-chip motor drive system of the utility model;

[0019] Figure 5 A flow chart for realizing sensed FOC control for the single-chip motor drive system of the utility model;

[0020] Figure 6 The flow chart of realizing sensorless FOC control for the single-chip motor drive system of the utility model;

[0021] Figure 7 A flow chart of Hall square wave control is implemented for the single-chip motor drive system of the utility model;

[0022] Figure 8 The present invention is a flow chart for realizing sensorless square wave control of a single-chip motor drive system. [Specific implementation method]

[0023] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below with reference to the accompanying drawings and implementation examples. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0024] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are limited to relative positions on the specified view rather than absolute positions.

[0025] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0026] See also Figures 1 to 4 The single-chip motor drive system of the utility model includes a power supply module, a single-chip microcomputer module, a pre-drive module and a three-phase bridge module. The pre-drive module is connected to the single-chip microcomputer module, the three-phase bridge module is connected to the pre-drive module, the three-phase bridge module is connected to the motor, and the power supply module is respectively connected to the single-chip microcomputer module, the pre-drive module and the three-phase bridge module.

[0027] The power supply module is used to provide power to the single-chip microcomputer module, the pre-driver module and the three-phase bridge module. The pre-driver module is used to convert the single-chip microcomputer logic level into a mosfet drive signal, and then send the mosfet drive signal to the three-phase bridge module.

[0028] The single-chip microcomputer module includes a processor CPU, an incremental encoder module, a HALL input module, an AD peripheral and a digital IO, and the incremental encoder module, the HALL input module, the AD peripheral and the digital IO are connected to the processor CPU through a data bus. The single-chip microcomputer module can implement the FOC algorithm of the incremental encoder, the FOC algorithm of the linear Hall sensor, the non-sensing FOC algorithm, the Hall three-phase six-beat algorithm and the Hall-free back electromotive force detection algorithm through software.

[0029] The single chip microcomputer module also includes a communication module, an operational amplifier module, a comparator module RAM and a ROM. The communication module, the operational amplifier module, the comparator module RAM and the ROM are connected to the processor CPU via a data bus.

[0030] The single chip microcomputer module also includes a timer counter module and a clock module, and the timer counter and the clock module are respectively connected to the processor CPU.

[0031] The single chip microcomputer module also includes a Hall input module, and the Hall input module is connected to the processor CPU.

[0032] The three-phase bridge module is composed of 3 NMOSFETs and 3 PMOSFETs, which are used to receive the pre-drive signal and output a high-voltage signal to realize the three-phase drive of the motor and the operation of the motor. The PWM control of the 6 channels of the motor drive control is connected to the pre-drive by a single chip, and then drives the three-phase bridge through the pre-drive to power the motor and run the motor.

[0033] See also Figures 5 to 8 The motor control algorithm is implemented by software. The incremental encoder module includes a PI controller, a CLARK transformation module, a PARK transformation module, a PARK inverse transformation module, a CLARKE inverse transformation module, an SVPWM module, a drive output peripheral module, a current sampling module, a voltage sampling module, a position speed angle calculation module, a position speed angle estimation module, a Hall sampling module, a Hall commutation module, a back electromotive force zero-crossing detection module, etc.

[0034] The current sampling module samples the phase current I a , I b , reconstruct I C , using dual resistor sampling. By using CLARKE transformation, the current is converted from I a , I b Convert to I α , I β ;

[0035] The voltage sampling module collects the three-phase terminal voltage of the motor and reconstructs the voltage V in the α-β stator coordinate system. α , V β ;

[0036] The position, speed and angle calculation module calculates the position, speed and angle information through an algorithm based on the signal of the incremental encoder or linear Hall.

[0037] The speed angle estimation module uses the voltage V α , V β and current I α , I β Estimate the current rotor angular position and rotor speed;

[0038] The PARK transformation module converts the current from I in the α-β stator coordinate system to α , I β Transformed to the dq coordinate system I that rotates with the rotor flux d , I q ;

[0039] Adoption I d =0 control mode, through the PI operation of the d-axis, the D-axis voltage u is obtained d ;

[0040] The q-axis reference current is calculated by PI to obtain the q-axis voltage u q ;

[0041] PARK inverse transformation converts the voltage vector u according to the rotor angle d ,u q Transforming from the rotating dq rotor coordinate system to the stationary α-β stator coordinate system, the voltage component u is obtained α ,u β ; Voltage component u α ,u β The voltage is transformed from the α-β stator coordinate system to the three-phase stator coordinate system through the CLARKE inverse transformation;

[0042] The SVPWM module calculates the corresponding duty cycle of 3 according to the voltage component;

[0043] The Hall sampling module outputs the acquired Hall state to the commutation module to realize the brushless motor control with Hall.

[0044] Back EMF zero-crossing detection, the commutation point calculation module uses the Hall back EMF information to determine the zero crossing through zero-crossing comparison. The commutation point information is output to the commutation module to realize the commutation operation of the motor.

[0045] See also Figure 5 , to achieve sensored FOC control:

[0046] Position command input: The system receives a position command, which usually comes from an external control unit or user input.

[0047] CLARK transformation: Convert the current in the three-phase coordinate system to the α (alpha) and β (beta) stationary coordinate system.

[0048] PARK transformation: Convert the current in the α (alpha) and β (beta) stationary coordinate system to the d-axis and q-axis coordinate system in the rotating reference frame.

[0049] SVPWM: Space Vector Pulse Width Modulation, is a modulation technique used to generate control signals for motors.

[0050] Pre-driver: Convert the motor control signal output by the microcontroller into a level signal suitable for three-phase bridge drive.

[0051] Three-phase bridge: The pre-driven three-phase signal drives the three-phase bridge circuit to operate the motor.

[0052] PMSM / BLDC: Permanent Magnet Synchronous Motor (PMSM) or Brushless Direct Current Motor (BLDC), which is the type of motor controlled by the drive system.

[0053] Linear Hall / Incremental Encoders: These are position feedback sensors used to detect the rotational position and speed of the motor.

[0054] Current sampling: Measure the motor current to facilitate current control.

[0055] PARK inverse transformation: Convert the voltage in the d and q coordinate systems to the voltage in the α and β coordinate systems.

[0056] CLARK inverse transformation: Convert the voltage in the α and β coordinate systems back to the three-phase coordinate system.

[0057] Position, speed, and angle calculation: Based on sensor feedback and system internal calculations, the position, speed, and angle information of the motor are calculated.

[0058] Speed ​​PID controller: Proportional-Integral-Derivative controller, used to control the speed of the motor.

[0059] Q_PI controller: refers to the PI controller on the q-axis, which is used to control the q-axis current of the motor.

[0060] Id_ref=0: indicates that in the control strategy, the reference value of the direct-axis current is set to 0.

[0061] D_PI controller: refers to the PI controller on the d-axis, used to control the d-axis current of the motor.

[0062] Figure 5 The complete process of the motor drive system from receiving instructions to executing control is demonstrated, including signal conversion, modulation, drive, feedback and control.

[0063] See also Figure 6 , realize sensorless FOC control:

[0064] Speed ​​Command: The system receives a speed command, which usually comes from an external control unit or user input.

[0065] D_PI controller: refers to the PI controller on the d-axis, used to control the d-axis current of the motor.

[0066] PARK transformation: Convert the current in the α (alpha) and β (beta) stationary coordinate system to the d-axis and q-axis coordinate system in the rotating reference frame.

[0067] CLARK transformation: Convert the current in the three-phase coordinate system to the α (alpha) and β (beta) stationary coordinate system.

[0068] SVPWM: Space Vector Pulse Width Modulation, is a modulation technique used to generate control signals for motors.

[0069] Pre-driver: Convert the motor control signal output by the microcontroller into a level signal suitable for three-phase bridge drive.

[0070] Three-phase bridge: The pre-driven three-phase signal drives the three-phase bridge circuit to operate the motor.

[0071] PMSM / BLDC: Permanent Magnet Synchronous Motor (PMSM) or Brushless Direct Current Motor (BLDC), which is the type of motor controlled by the drive system.

[0072] PARK inverse transformation: Convert the voltage in the d and q coordinate systems to the voltage in the α and β coordinate systems.

[0073] CLARK inverse transformation: converts the voltage in the α and β coordinate systems back to the three-phase coordinate system. Speed ​​PID controller: Proportional-integral-derivative controller used to control the speed of the motor.

[0074] Q_PI controller: refers to the PI controller on the q-axis, which is used to control the q-axis current of the motor.

[0075] Ig: refers to the current feedback signal of the motor.

[0076] Angle, Id, Iq: These signals are related to the rotor position, direct-axis current, and quadrature-axis current of the motor.

[0077] Current sampling: Measure the motor current to facilitate current control.

[0078] Position speed estimation module: used to estimate the speed of the motor based on the motor's back EMF or other sensor information.

[0079] Voltage sampling: Measure the voltage of the motor to facilitate voltage control or feedback.

[0080] Figure 6 The complete process of the motor drive system from receiving speed instructions to executing control is demonstrated, including signal conversion, modulation, drive, feedback and control. Figure 5 compared to, Figure 6 More emphasis is placed on the details of speed control and current control.

[0081] See also Figure 7 , realize Hall square wave control:

[0082] Speed ​​command input: The system receives speed commands from an external control unit or user.

[0083] Pre-driver: Convert the motor control signal output by the microcontroller into a level signal suitable for three-phase bridge drive.

[0084] Commutation module: responsible for the commutation logic of the motor, ensuring that the phase of the motor is switched correctly to maintain rotation.

[0085] Output: The signal processed by the pre-drive and commutation modules is output to the motor drive part.

[0086] Three-phase bridge: The pre-driven three-phase signal drives the three-phase bridge circuit to operate the motor.

[0087] PMSM / BLDC: Permanent Magnet Synchronous Motor (PMSM) or Brushless Direct Current Motor (BLDC), the type of motor controlled by the drive system.

[0088] Speed ​​PID: Closed-loop control of speed, using a proportional-integral-derivative controller to adjust the speed of the motor to ensure it reaches the command speed.

[0089] Current PID: Closed-loop control of current, using a proportional-integral-derivative controller to regulate the current to the motor to improve efficiency and stability.

[0090] Switching Hall: Hall effect sensors are used to detect the position of the motor rotor for accurate commutation and speed control.

[0091] Current feedback: The actual current of the motor is measured through the current sampling circuit, and this information is fed back to the current PID controller.

[0092] Speed ​​feedback: By measuring the speed of the motor, the speed information is fed back to the speed PID controller.

[0093] Current sampling: measures the motor current and is used for current regulation by the current PID controller.

[0094] Speed ​​calculation: Calculate the actual speed of the motor based on the speed feedback signal.

[0095] Hall sampling module: Use Hall effect sensors to collect the position information of the motor rotor for use in the motor control algorithm.

[0096] See also Figure 8 , realize sensorless square wave control:

[0097] Speed ​​command input: This is the starting point of the control process. The user or system provides a speed command, which specifies the speed that the motor should reach.

[0098] Speed ​​PID module: Receives speed command and compares it with the actual speed of the motor. PID stands for Proportional, Integral, Derivative, and is a common feedback controller used to reduce the error between the system output and the desired value.

[0099] Current PID module: Similarly, this module receives the current command value and compares it with the actual current of the motor to adjust the current through PID control.

[0100] Pre-driver: Convert the motor control signal output by the microcontroller into a level signal suitable for three-phase bridge drive.

[0101] Three-phase bridge: The pre-driven three-phase signal drives the three-phase bridge circuit to operate the motor.

[0102] Phase commutation module: The motor needs to continuously change phases to maintain rotation during operation. The phase commutation module is responsible for managing this process and ensuring that the motor phases are switched correctly.

[0103] Output: Finally, after the above control process, the motor drive signal is output to the motor to drive the motor to run.

[0104] PMSM / BLDC: Permanent Magnet Synchronous Motor (PMSM) or Brushless Direct Current Motor (BLDC), which is the type of motor controlled by the drive system.

[0105] Current feedback: When the motor is running, the motor current is monitored in real time and this information is fed back to the current PID module.

[0106] Speed ​​Feedback: The real-time speed of the motor is also monitored and this information is fed back to the speed PID module.

[0107] Current sampling: This is a step of current feedback, which obtains the current information of the motor through sampling.

[0108] Back EMF zero-crossing point calculation: In a brushless DC motor (BLDC), the detection of the back EMF zero-crossing point is very important for determining the phase of the motor.

[0109] Back-EMF sampling: This is a step to obtain the motor's back-EMF information, which helps control the motor's commutation timing.

[0110] Speed ​​calculation point control module: This module may be responsible for calculating the speed of the motor and determining when phase switching is required to maintain stable operation of the motor.

[0111] Compared with the prior art, the single-chip motor drive system of the utility model has the following beneficial effects:

[0112] 1. The entire process of motor control can be directly realized through a single chip, with high integration, high reliability, and small size, and can be used in occasions where the PCB size is limited;

[0113] 2. The algorithm is implemented through software, with good scalability, the main frequency of the microcontroller is 48MHz, or higher main frequency 96MHz, 192MHz, and fast real-time performance;

[0114] 3. It can realize various motor control methods such as sensed FOC, senseless FOC, sensed square wave brushless and senseless square wave brushless motor control to meet the different needs of different users.

[0115] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any modifications, equivalent substitutions and improvements made within the concept of the present invention should be included in the patent protection scope of the present invention.

Claims

1. A single-chip motor drive system, characterized in that: It includes a power supply module, a single-chip computer module, a pre-driving module and a three-phase bridge module, wherein the pre-driving module is connected to the single-chip computer module, the three-phase bridge module is connected to the pre-driving module, the three-phase bridge module is connected to the motor, and the power supply module is respectively connected to the single-chip computer module, the pre-driving module and the three-phase bridge module; The power supply module is used to provide power to the single-chip microcomputer module, the pre-driver module, and the three-phase bridge module; The pre-driver module is used to convert the single-chip microcomputer logic level into a mosfet drive signal, and then send the mosfet drive signal to the three-phase bridge module; The single chip microcomputer module comprises a processor CPU, an incremental encoder module, a HALL input module, an AD peripheral and a digital IO, and the incremental encoder module, the HALL input module, the AD peripheral and the digital IO are connected to the processor CPU via a data bus.

2. The single-chip motor drive system according to claim 1, characterized in that: The single chip microcomputer module comprises a communication module, an operational amplifier module, a comparator module RAM and a ROM, and the communication module, the operational amplifier module, the comparator module RAM and the ROM are connected to a processor CPU via a data bus.

3. The single-chip motor drive system according to claim 1, characterized in that: The single chip microcomputer module comprises a timer counter module and a clock module, and the timer counter and the clock module are respectively connected to the processor CPU.

4. The single-chip motor drive system according to claim 1, characterized in that: The single chip microcomputer module comprises a Hall input module, and the Hall input module is connected to a processor CPU.

5. The single-chip motor drive system according to claim 1, characterized in that: The three-phase bridge module is composed of three NMOSFETs and three PMOSFETs, and is used to receive a pre-drive signal and output a high-voltage signal to realize three-phase drive of the motor and operation of the motor.

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