CN-114696674-B - Brushless motor control method and device, electric control device and storage medium

CN114696674BCN 114696674 BCN114696674 BCN 114696674BCN-114696674-B

Abstract

The application discloses a brushless motor control method, a brushless motor control device, an electric control device and a storage medium, and belongs to the technical field of circuit control. The method is applied to an electric control device and comprises the steps of obtaining a first duty ratio, wherein the first duty ratio is the duty ratio of a driving signal, obtaining a reversing coefficient according to the first duty ratio and a reversing function, wherein the reversing function is used for indicating a coefficient curve between the reversing coefficient and the first duty ratio when the electric angle of the brushless motor reverses, calculating the electric angle reversing time of the brushless motor according to the reversing coefficient, and controlling the brushless motor to reverse according to the electric angle reversing time and an idle signal. The application can flexibly acquire the reversing coefficients under different conditions based on the duty ratio and the reversing function, thereby calculating the electric angle reversing time of the brushless motor, reversing without setting fixed electric angle reversing time, and improving the reversing effect of the electric control device for controlling the brushless motor.

Inventors

XU CHAO

Assignees

未来穿戴健康科技股份有限公司
未来穿戴健康科技股份有限公司

Dates

Publication Date: 20260421
Application Date: 20220303
Priority Date: 20220303

Claims (13)

1. The method is applied to an electric control device, the electric control device comprises a brushless motor and a power supply control unit, a reversing function is preset in the power supply control unit, when the electric control device works, the power supply control unit generates a driving signal and an idle signal, the driving signal is used for driving the brushless motor to work, the waveform of the driving signal is the same as that of the idle signal, the frequency of the idle signal is the same as that of the driving signal, and the control method comprises the following steps: acquiring a first duty cycle, wherein the first duty cycle is the duty cycle of the driving signal; Acquiring a reversing coefficient according to the first duty cycle and a reversing function, wherein the reversing function is used for indicating a coefficient curve between the reversing coefficient and the first duty cycle when the electric angle of the brushless motor reverses; According to the reversing coefficient, calculating the electric angle reversing time of the brushless motor; and controlling the brushless motor to commutate according to the electric angle commutation time and the idle signal.
2. The method of claim 1, further comprising, prior to said obtaining a commutation coefficient from said first duty cycle and a commutation function: determining a sampling period for sampling back electromotive force of the brushless motor according to the first duty ratio; collecting the back electromotive force of the brushless motor according to the sampling period; Detecting whether a zero-crossing event occurs after the back electromotive force of the brushless motor is acquired; and if the zero crossing event occurs, executing the step of acquiring the reversing coefficient according to the first duty ratio and the reversing function.
3. The method of claim 2, wherein determining a sampling period for sampling back emf of the brushless motor based on the first duty cycle comprises: Determining a second duty cycle according to the first duty cycle, wherein the second duty cycle is the duty cycle of the idle signal; And determining a sampling period for sampling the back electromotive force of the brushless motor according to the second duty ratio.
4. A method according to claim 3, wherein said determining a second duty cycle from said first duty cycle comprises: If the first duty cycle is greater than a first preset threshold, determining the second duty cycle based on a first standard; and if the first duty ratio is smaller than or equal to the first preset threshold value, determining the second duty ratio based on a second standard.
5. The method of claim 2, wherein detecting whether a zero-crossing event occurs after the back emf of the brushless motor is collected comprises: Acquiring an occurrence mark of a zero crossing event of the brushless motor; and detecting whether a zero crossing event occurs according to the occurrence identification.
6. The method of claim 5, wherein said controlling the commutation of the brushless motor based on the electrical angle commutation time and the idle signal comprises: Detecting whether the electrical angle commutation time is reached; If the current value reaches the preset value, controlling the brushless motor to commutate; And if the zero crossing event does not arrive, executing the step of acquiring the occurrence identification of the zero crossing event of the brushless motor.
7. The method of any of claims 1 to 6, further comprising, prior to said obtaining the first duty cycle: acquiring operation parameters of the electric control device; According to the operation parameters of the electric control device, adjusting the operation parameters of the driving signals; the obtaining the first duty cycle includes: And acquiring the duty ratio corresponding to the adjusted driving signal.
8. The method according to any one of claims 1 to 6, wherein the commutation function comprises a first function and a second function, and wherein the obtaining the commutation coefficients from the first duty cycle and the commutation function comprises: if the first duty ratio is larger than a second preset threshold value, acquiring the reversing coefficient according to the first duty ratio and the first function; and if the first duty ratio is smaller than or equal to the second preset threshold value, acquiring the reversing coefficient according to the first duty ratio and the second function.
9. The method according to any one of claims 1 to 6, wherein said calculating an electrical angle commutation time of said brushless motor based on said commutation coefficients comprises: acquiring a time difference between the last reversing time of the brushless motor and the current time; And determining the electric angle reversing time of the brushless motor according to the time difference and the reversing coefficient.
10. The method according to any one of claims 1 to 6, wherein prior to said obtaining the first duty cycle, the method further comprises: Determining a plurality of test values; Adjusting the first duty ratio to each test value, and obtaining the electric angle reversing time corresponding to each test value; determining the reversing coefficients corresponding to the test values according to the electric angle reversing time corresponding to the test values; Acquiring the reversing function according to each testing value and the reversing coefficient corresponding to each testing value; and storing the reversing function to the power supply control unit.
11. The utility model provides a brushless motor's controlling means, its characterized in that, the device is applied to electric control device, electric control device includes brushless motor and power control unit, preset the switching-over function in the power control unit, when electric control device works, power control unit produces drive signal and idle running signal, drive signal is used for driving brushless motor work, drive signal's wave form is the same with idle running signal wave form, idle running signal's frequency is the same with drive signal's frequency, controlling means includes: a first acquisition module configured to acquire a first duty cycle, the first duty cycle being a duty cycle of the driving signal; the second acquisition module is used for acquiring a reversing coefficient according to the first duty cycle and a reversing function, wherein the reversing function is used for indicating a coefficient curve between the reversing coefficient and the first duty cycle when the electric angle of the brushless motor is reversed; the first calculation module is used for calculating the electric angle reversing time of the brushless motor according to the reversing coefficient; and the steering control module is used for controlling the brushless motor to commutate according to the electric angle commutation time and the idle signal.
12. An electronic control device, characterized in that the electronic control device comprises a memory and a processor, wherein the memory stores a computer program, and the computer program, when executed by the processor, causes the processor to implement the method for controlling a brushless motor according to any one of claims 1 to 10.
13. A computer-readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements a method for controlling a brushless motor according to any one of claims 1 to 10.

Description

Brushless motor control method and device, electric control device and storage medium Technical Field The embodiment of the application relates to the technical field of circuit control, in particular to a brushless motor control method, a brushless motor control device, an electric control device and a storage medium. Background Along with the progress of scientific technology, many electric control devices used in daily life are equipped with brushless motors, and the electric control devices realize control of different functions through switching of the brushless motors. Currently, in most electronic control devices, the rotor position of the motor needs to be precisely known for controlling the brushless motor, and a central processing unit (Central Processing Unit, CPU) of the electronic control device can precisely control the brushless motor to perform commutation. In general, the electric control device uses some sensors such as hall elements and encoders to detect the mechanical angle of the motor, and there is no sensing (i.e. no sensor) brushless motor. For a brushless motor without sense, three counter electromotive forces of the motor are generally detected to calculate a mechanical angle and then the calculated electrical angle is delayed by 30 electrical angles according to a theoretical value to perform fixed commutation, namely, the brushless motor is commutated by adopting a fixed delay electrical angle, but because of the difference in commutation time of different design circuits and different motor performances, the brushless motor is commutated according to the fixed delay electrical angle at different rotating speeds, and the problems of poor effect and low flexibility of the obtained commutation result exist. Disclosure of Invention The embodiment of the application provides a brushless motor control method, a brushless motor control device, an electric control device and a storage medium, which can flexibly calculate the reversing coefficients under different conditions and improve the reversing effect of the electric control device on the brushless motor. In one aspect, an embodiment of the present application provides a method for controlling a brushless motor, where the method is applied to an electronic control device, the electronic control device includes a brushless motor and a power control unit, a commutation function is preset in the power control unit, when the electronic control device works, the power control unit generates a driving signal and an idle signal, the driving signal is used for driving the brushless motor to work, a waveform of the driving signal is the same as a waveform of the idle signal, a frequency of the idle signal is the same as a frequency of the driving signal, and the control method includes: acquiring a first duty cycle, wherein the first duty cycle is the duty cycle of the driving signal; Acquiring a reversing coefficient according to the first duty cycle and a reversing function, wherein the reversing function is used for indicating a coefficient curve between the reversing coefficient and the first duty cycle when the electric angle of the brushless motor reverses; According to the reversing coefficient, calculating the electric angle reversing time of the brushless motor; and controlling the brushless motor to commutate according to the electric angle commutation time and the idle signal. Optionally, before the step of obtaining the commutation coefficient according to the first duty cycle and the commutation function, the method further includes: determining a sampling period for sampling back electromotive force of the brushless motor according to the first duty ratio; collecting the back electromotive force of the brushless motor according to the sampling period; Detecting whether a zero-crossing event occurs after the back electromotive force of the brushless motor is acquired; and if the zero crossing event occurs, executing the step of acquiring the reversing coefficient according to the first duty ratio and the reversing function. Optionally, the determining, according to the first duty cycle, a sampling period for sampling a back electromotive force of the brushless motor includes: Determining a second duty cycle according to the first duty cycle, wherein the second duty cycle is the duty cycle of the idle signal; And determining a sampling period for sampling the back electromotive force of the brushless motor according to the second duty ratio. Optionally, determining the second duty cycle according to the first duty cycle includes: If the first duty cycle is greater than a first preset threshold, determining the second duty cycle based on a first standard; and if the first duty ratio is smaller than or equal to the first preset threshold value, determining the second duty ratio based on a second standard. Optionally, after the back electromotive force of the brushless motor is collected, detecting whether a zero-crossing event oc