A control method for a brushless motor and an electronic commutator

Abstract

The present application provides a control method and an electronic commutator for a brushless motor, the control method comprising: collecting the input phase voltage of each motor winding in the brushless motor, and obtaining the state parameter of the brushless motor according to each input phase voltage; collecting the freewheeling voltage of each motor winding in the brushless motor, wherein the freewheeling voltage is an interference signal generated by the electronic commutator when commutating the input voltage in the motor winding; adjusting at least one state parameter of each motor winding according to the freewheeling voltage, so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively. The present application eliminates the influence of the freewheeling voltage on the operation of the brushless motor and greatly improves the rotation efficiency of the brushless motor.

Description

Technical Field

[0001] The present application relates to the technical field of control or regulation of electric motors, and in particular to a control method and an electronic commutator for a brushless motor. Background Art

[0002] The electronic commutator switches the voltage direction of the electronic winding in the brushless motor by turning on and off multiple switching elements. When the electronic commutator switches the voltage direction of the motor winding, due to the action of the switching elements, the current will not be interrupted immediately, but will continue to flow through the freewheeling path to generate a freewheeling voltage.

[0003] The freewheeling voltage will affect the voltage value and phase of the input phase voltage, thereby reducing the rotation efficiency of the brushless motor. Summary of the invention

[0004] The present application provides a control method for a brushless motor and an electronic commutator, which are used to solve the problem that the rotation efficiency of the brushless motor is reduced due to the freewheeling voltage affecting the input phase voltage.

[0005] In a first aspect, the present application provides a control method for a brushless motor, which operates in an electronic commutator of the brushless motor, comprising:

[0006] The input phase voltage of each motor winding in the brushless motor is collected, and the state parameter of the brushless motor is obtained according to each input phase voltage; wherein the input phase voltage is a sinusoidal wave voltage input to a phase motor winding in the brushless motor; the types of the state parameters include: the duty cycle of the input phase voltage received by the motor winding, the voltage value of the input phase voltage of the motor winding, the commutation point of the motor winding and the commutation lead angle of the motor winding; the commutation point is the phase in the input phase voltage used to change the voltage direction of the motor winding; the commutation lead angle is the angle difference between the commutation angle and the real-time angle of the rotor of the brushless motor; the commutation angle is the rotation angle of the rotor when the voltage direction in the motor winding changes; the real-time angle is the rotation angle of the rotor when the motor control signal is generated; the motor control signal is an electrical signal used to instruct the electronic commutator to change the voltage direction in the motor winding;

[0007] Collecting the freewheeling voltage of each motor winding in the brushless motor, wherein the freewheeling voltage is an interference signal generated by the electronic commutator when commutating the input voltage in the motor winding;

[0008] At least one state parameter of each motor winding is adjusted according to the freewheeling voltage, so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively.

[0009] In the above scheme, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0010] The duty cycle of the first input phase voltage is adjusted according to the first freewheeling voltage to obtain a first modified voltage; wherein the first freewheeling voltage is a freewheeling voltage corresponding to the first motor winding; the first motor winding is one of at least one of the motor windings; the first input phase voltage is an input phase voltage input to the first motor winding;

[0011] The brushless motor is driven by a first modified voltage of at least one of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

[0012] In the above scheme, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0013] The voltage value of the second input phase voltage is adjusted according to the second freewheeling voltage to obtain a second modified voltage; wherein the second freewheeling voltage is a freewheeling voltage corresponding to the second motor winding; the second motor winding is one of at least one of the motor windings; the second input phase voltage is an input phase voltage input to the second motor winding;

[0014] The brushless motor is driven by a second modified voltage of at least one of the motor windings so that a commutation angle of the rotor on each of the motor windings matches a commutation point of each of the motor windings.

[0015] In the above scheme, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0016] The phase of the third input phase voltage is adjusted according to the third freewheeling voltage to obtain a third modified voltage; wherein the third freewheeling voltage is a freewheeling voltage corresponding to a third motor winding; and the third motor winding is one of at least one of the motor windings;

[0017] The brushless motor is driven by a third modified voltage of at least one of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

[0018] In the above scheme, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0019] adjusting the commutation lead angle of the rotor to the fourth motor winding according to the fourth freewheeling voltage; wherein the fourth freewheeling voltage is a freewheeling voltage corresponding to the fourth motor winding; and the fourth motor winding is one of at least one of the motor windings;

[0020] The brushless motor is driven by an input phase voltage of at least one of the motor windings, and the voltage direction in each of the motor windings is controlled according to the adjusted commutation advance angle of each of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

[0021] In the above scheme, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0022] The duty cycle and / or voltage value of the fifth input phase voltage is adjusted according to the fifth freewheeling voltage to obtain a fifth initial correction voltage; wherein the fifth freewheeling voltage is a freewheeling voltage corresponding to the fifth motor winding; the fifth motor winding is one of at least one of the motor windings; the fifth input phase voltage is an input phase voltage input to the fifth motor winding;

[0023] The phase of the fifth initial modified voltage is adjusted according to the fifth freewheeling voltage to obtain a fifth modified voltage; wherein the fifth freewheeling voltage is a freewheeling voltage corresponding to a fifth motor winding; and the fifth motor winding is one of at least one of the motor windings;

[0024] The brushless motor is driven by a fifth modified voltage of at least one of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

[0025] In the above scheme, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0026] The duty cycle and / or voltage value of the sixth input phase voltage is adjusted according to the sixth freewheeling voltage to obtain a sixth modified voltage; wherein the sixth freewheeling voltage is a freewheeling voltage corresponding to the sixth motor winding; the sixth motor winding is one of at least one of the motor windings; and the sixth input phase voltage is an input phase voltage input to the sixth motor winding;

[0027] Adjusting the commutation lead angle of the rotor to the sixth motor winding according to the sixth freewheeling voltage; wherein the sixth freewheeling voltage is a freewheeling voltage corresponding to the sixth motor winding; and the sixth motor winding is one of at least one of the motor windings;

[0028] The brushless motor is driven by the sixth modified voltage of at least one of the motor windings and the modified commutation advance angle of each of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

[0029] In the above scheme, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0030] The phase of the seventh input phase voltage is adjusted according to the seventh freewheeling voltage to obtain a seventh modified voltage; wherein the seventh freewheeling voltage is a freewheeling voltage corresponding to the seventh motor winding; and the seventh motor winding is one of at least one of the motor windings;

[0031] adjusting the commutation lead angle of the rotor to the seventh motor winding according to the seventh freewheeling voltage; wherein the seventh freewheeling voltage is a freewheeling voltage corresponding to the seventh motor winding; and the seventh motor winding is one of at least one of the motor windings;

[0032] The brushless motor is driven by the seventh modified voltage of at least one of the motor windings and the modified commutation advance angle of each of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

[0033] In the above scheme, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0034] The duty cycle and / or voltage value of the eighth input phase voltage is adjusted according to the eighth freewheeling voltage to obtain an eighth primary correction voltage; wherein the eighth freewheeling voltage is a freewheeling voltage corresponding to the eighth motor winding; the eighth motor winding is one of at least one of the motor windings; the eighth input phase voltage is an input phase voltage input to the eighth motor winding;

[0035] The phase of the eighth primary modified voltage is adjusted according to the eighth freewheeling voltage to obtain an eighth modified voltage; wherein the eighth freewheeling voltage is a freewheeling voltage corresponding to the eighth motor winding; and the eighth motor winding is one of at least one of the motor windings;

[0036] adjusting the commutation lead angle of the rotor to the eighth motor winding according to the eighth freewheeling voltage; wherein the eighth freewheeling voltage is a freewheeling voltage corresponding to the eighth motor winding; and the eighth motor winding is one of at least one of the motor windings;

[0037] The brushless motor is driven by the eighth modified voltage of at least one of the motor windings and the modified commutation advance angle of each of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

[0038] In a second aspect, the present application provides an electronic commutator installed in a brushless motor, wherein the above-mentioned brushless motor control method is executed in the electronic commutator.

[0039] The present application provides a control method and electronic commutator for a brushless motor, which achieves the technical effect of comprehensively collecting the current operating status of the brushless motor by collecting the input phase voltage of each motor winding in the brushless motor and obtaining the state parameters of the brushless motor based on each input phase voltage.

[0040] By adjusting the state parameters according to the freewheeling voltage, the rotor of the brushless motor is matched with the commutation point of each motor winding when it rotates to the commutation angle on each motor winding. This makes the rotor exactly at the commutation point of the input phase current when it rotates to the commutation angle. At this time, the motor winding switches the voltage direction according to the commutation point, eliminating the influence of the freewheeling voltage on the operation of the brushless motor and achieving the technical effect of improving the rotation efficiency of the brushless motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0042] Figure 1 A flow chart of a method for controlling a brushless motor provided in the present application.

[0043] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0044] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the embodiments of the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the embodiments of the present application as detailed in the appended claims.

[0045] The following specific embodiments are used to describe in detail the technical solutions of the embodiments of the present application and how the technical solutions of the embodiments of the present application solve the current problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0046] The following embodiments are now provided:

[0047] Example 1: Please refer to Figure 1 The present application provides a control method for a brushless motor, which operates in an electronic commutator of the brushless motor, comprising:

[0048] S101: Collect the input phase voltage of each motor winding in the brushless motor, and obtain the state parameters of the brushless motor according to each input phase voltage; wherein the input phase voltage is a sinusoidal wave voltage input to a phase motor winding in the brushless motor; the types of state parameters include: the duty cycle of the input phase voltage received by the motor winding, the voltage value of the input phase voltage of the motor winding, the commutation point of the motor winding and the commutation lead angle of the motor winding; the commutation point is the phase in the input phase voltage used to change the voltage direction of the motor winding; the commutation lead angle is the angle difference between the commutation angle and the real-time angle of the rotor of the brushless motor; the commutation angle is the rotation angle of the rotor when the voltage direction in the motor winding changes; the real-time angle is the rotation angle of the rotor when the motor control signal is generated; the motor control signal is an electrical signal used to instruct the electronic commutator to change the voltage direction in the motor winding.

[0049] In this step, the current operation status of the brushless motor is comprehensively collected by collecting the input phase voltage of each motor winding in the brushless motor and obtaining the state parameters of the brushless motor according to each input phase voltage.

[0050] In a preferred embodiment, collecting the phase voltage of each motor winding in the brushless motor includes:

[0051] S11: If it is detected that the brushless motor receives voltage, the voltage at the input end of each motor winding in the brushless motor is collected through a sampling circuit to obtain the input phase voltage of each motor winding.

[0052] In this example, the input terminal of the brushless motor is detected by a voltmeter preset in the electronic commutator to determine whether the brushless motor is started.

[0053] The sampling circuit is used to measure the motor voltage, and the sampling circuit includes a voltage sensor.

[0054] The voltage sensor is used to convert the motor voltage into a measurable signal. In this embodiment, the measurable signal is a voltage signal. The voltage sensor is one or more of a Hall effect sensor, a resistive sensor, and a magnetoresistive sensor; the Hall effect sensor is used to convert the voltage into a voltage signal proportional to it using the Hall effect principle, and has the advantages of high precision, good linearity, and strong temperature stability, but the cost is relatively high. The resistive sensor is used to convert the voltage into a voltage drop across the resistor by connecting a low-resistance resistor in series in the motor line. It is simple to implement and has low cost, but it will introduce a certain amount of power loss, and has high requirements for the accuracy and temperature stability of the resistor. The magnetoresistive sensor is used to detect voltage using the magnetoresistive effect, and has the advantage of non-contact measurement, but may be affected by magnetic field interference.

[0055] The sampling circuit also has one or more of the voltage transformer, voltage transmitter and photoelectric coupler; isolation devices such as voltage transformer and voltage transmitter are used to isolate the sampling signal from the main circuit loop to reduce the interference caused by coupling. Photoelectric couplers (optical couplers) are used at the signal input and output ends to replace electrical signal transmission with optical signal transmission to achieve electrical isolation and further improve anti-interference capabilities.

[0056] In a preferred embodiment, the state parameters of the brushless motor are obtained according to each input phase voltage, including:

[0057] S12: conditioning and amplifying at least one input phase voltage to obtain at least one filtered voltage signal;

[0058] S13: Detecting a duty cycle and a voltage value of at least one filtered voltage signal;

[0059] S14: determining at least one line voltage of the brushless motor according to at least one filtered voltage signal, and using a point where the voltage value of the line voltage is zero as a commutation point of the motor winding corresponding to two phase voltages in the line voltage; wherein the line voltage is a voltage difference between two phase voltages in the brushless motor;

[0060] S15: obtaining a commutation advance angle preset in the electronic commutator for each electronic winding; wherein the commutation advance angle is parameter information preset in the electronic commutator;

[0061] S16: Summarize the duty cycle, voltage value and commutation point of the filtered voltage signal corresponding to the motor winding, and the commutation lead angle of the electronic winding to obtain the state parameters of the electronic winding.

[0062] In this example, the input phase voltage is conditioned and amplified to eliminate the stray current in the input phase voltage; the line voltage of the brushless motor is determined based on the filtered voltage signal, and the point where the line voltage value is zero is used as the natural commutation point of the motor winding corresponding to the two phase voltages in the line voltage, thereby ensuring the accuracy of the subsequent recognition of the natural commutation point and ensuring that the brushless motor can commutate the voltage in the motor winding in time when the line voltage is zero, thereby ensuring the smooth operation of the motor.

[0063] Exemplarily, the input phase voltage received by each motor winding has a voltage value of [-220V~+220V], and the phase difference of each input phase voltage is 120°.

[0064] If the input phase voltage is a continuous voltage, it means that the current duty cycle of the input phase voltage is 100%. If the input phase voltage is a pulse voltage, the duty cycle of the input voltage is in the range of (0,100%).

[0065] The commutation point of each motor winding of the brushless motor is the time point when the line voltage corresponding to the motor winding is 0, that is, the natural commutation point of each motor winding. The natural commutation point is the point where the two-phase input phase voltage waveforms intersect among the three input phase voltages, that is, the time point 30° after the input phase voltage of the motor winding passes through zero.

[0066] The commutation lead angle of each motor winding of the brushless motor is between (0~60°). In the motor control system, in order to predict and control the motion trajectory of the motor rotor, the position signal of the motor rotor is advanced by a certain angle. This control strategy aims to improve the speed control accuracy and performance of the motor. In the motor control system, the implementation of the lead angle usually relies on advanced control algorithms and sensor technology. The sensor monitors the position of the motor rotor in real time and feeds this information back to the control system. The control system calculates the lead angle based on this information and adjusts the control signal of the motor to achieve precise speed and position control. In other words, if the commutation lead angle is 30° and the commutation angle is 60°, that is, when the rotor rotates to 60°, the voltage direction of the motor winding needs to be changed. Therefore, when the sensor collects the real-time angle of the rotor as 30°, it is necessary to generate a motor control signal. The motor control signal controls the switch elements in the electronic commutator to open and / or close, changing the direction of the voltage in the motor winding. The process of fully opening and / or closing the switch elements requires time. Usually, under ideal conditions, this time is just enough for the rotor to rotate from 30° to 60°. That is, when the rotor rotates to 60°, the switch elements are fully opened or fully closed to change the direction of the voltage in the motor winding, thereby allowing the rotor to continue rotating.

[0067] At the same time, under ideal conditions, when the rotor rotates to 60°, the phase of the input phase voltage received by the corresponding motor winding is exactly 30° after the zero point (that is, the natural commutation point mentioned above), allowing the rotor to continue to rotate efficiently.

[0068] Specifically, conditioning and amplifying at least one input phase voltage to obtain at least one filtered voltage signal includes:

[0069] S121: Condition at least one input phase voltage signal to obtain at least one conditioned signal.

[0070] In this step, the phase voltage signal is conditioned by a signal conditioning circuit to obtain a conditioned signal. The signal conditioning circuit is used to further process the voltage signal output by the sensor to meet the requirements of subsequent acquisition and processing circuits.

[0071] In this embodiment, before the amplification process, the original phase voltage signal is usually conditioned to ensure the stability and reliability of the signal. The conditioning process of the signal conditioning circuit includes filtering, isolation and conversion.

[0072] Filtering is used to remove high-frequency noise and interference in the signal to ensure the purity of the signal. The type and parameters of the filter need to be determined based on the frequency characteristics and noise characteristics of the signal.

[0073] Isolation processing is used to prevent mutual influence between signals or protect subsequent circuits from the impact of high-voltage signals through isolation devices such as optocouplers and transformers.

[0074] Conversion processing is used to transform the properties of a signal through a resistor or an operational amplifier, for example: converting a current signal into a voltage signal; if the form of the original signal is not suitable for direct amplification (such as a current signal needs to be converted into a voltage signal), signal conversion is required.

[0075] Specifically, the signal conditioning circuit also includes: a conditioning filter circuit. The conditioning filter circuit is used to remove noise and interference in the sensor output signal and improve the quality and accuracy of the signal. The design of the filter circuit needs to consider the frequency characteristics and noise characteristics of the signal to ensure the filtering effect. Since the motor will generate large electromagnetic interference when working, the sampling circuit needs to have good anti-interference ability to ensure the accuracy of the measurement. The conditioning filter circuit includes: a low-pass filter and / or an active filter; low-pass filtering is used to add a low-pass filter to the sampling circuit to filter out high-frequency noise and interference signals. This can be achieved by connecting appropriate resistors, capacitors and inductors in series or in parallel in the circuit; active filtering is used to construct a filter using active devices such as operational amplifiers (op amps) to provide a more flexible and accurate filtering effect. Exemplarily, an active filter composed of an RC circuit combined with an op amp can more effectively suppress high-frequency noise.

[0076] The main purpose of filtering is to: Remove noise: Signals are often interfered by various noises during transmission or acquisition. Filtering can effectively remove these noises and improve the signal-to-noise ratio. Extract useful information: Through filtering, useful information in the signal can be selectively retained, and irrelevant or interfering information can be removed, thereby more accurately reflecting the characteristics of the signal. Improve signal quality: Filtering can make the signal smoother and more stable, reduce signal fluctuations and distortion, and improve signal quality.

[0077] The circuit used to condition the phase voltage signal in the conditioning filter circuit to obtain the conditioned signal is an analog filter circuit. The analog filter circuit (such as RC circuit, LC circuit or operational amplifier, etc.) is used to filter the signal. Analog filtering has the advantages of good real-time performance and low cost, but the filtering effect is greatly affected by the parameters of circuit components.

[0078] S122: Amplify at least one conditioned signal to obtain at least one conditioned amplified signal.

[0079] In this step, the signal conditioning circuit includes: a conditioning amplifier circuit; the conditioning amplifier circuit is used to increase the voltage signal output by the sensor so that it can better meet the requirements of the subsequent acquisition and processing circuit. The gain of the amplifier circuit needs to be adjusted according to the specific application scenario.

[0080] The conditioning amplifier circuit includes gain parameters and bandwidth parameters.

[0081] The gain parameter of the amplifier circuit needs to be determined according to the actual amplitude of the signal and the requirements of the subsequent processing circuit. Too large a gain may cause signal distortion, while too small a gain may not meet the requirements of subsequent processing.

[0082] The bandwidth parameter of the amplifier circuit needs to cover the frequency range of the signal to ensure that the signal is not distorted during the amplification process.

[0083] The conditioning amplifier circuit itself may also generate noise. Therefore, the noise power of the conditioning amplifier circuit is reduced by using metal film or thin film resistors in the conditioning amplifier circuit. Compared with traditional carbon film resistors, metal film or thin film resistors have lower noise power.

[0084] The conditioning amplifier circuit has a metal casing. For critical amplifier circuits, the metal casing can serve as a "shielding box" to effectively prevent the entry of external noise.

[0085] The conditioning amplifier circuit has a filter capacitor to eliminate noise in the power supply line. The filter capacitor can short-circuit high-frequency noise to ground, thereby reducing the possibility of it propagating to the operational amplifier.

[0086] The conditioning amplifier circuit has a heat sink and a fan, which are used to improve the heat dissipation efficiency of the conditioning amplifier circuit, thereby reducing the temperature of the conditioning amplifier circuit. Since the temperature increase will increase the thermal noise of the components and reduce the anti-noise performance of the circuit. Therefore, heat dissipation measures such as adding heat sinks and fans can control the temperature and reduce noise.

[0087] The circuit used to amplify the conditioned signal in the conditioning amplifier circuit to obtain the conditioned amplified signal is a differential amplifier circuit. The differential amplifier circuit has the effect of suppressing zero drift and can improve the stability and temperature resistance of the circuit. The differential amplifier circuit is a circuit that performs a differential operation on two input signals and then amplifies the difference and outputs it. Its working principle is based on the basic principle of the amplifier circuit. Through the differential input structure, the difference between the two input signals is used as an effective input signal, which is amplified by the internal circuit and then output. The core part of the differential amplifier circuit consists of two common-mode input parts and a differential input part. The two common-mode input parts are used to receive input signals and generate common-mode voltages; while the differential input part is used to extract the difference between the two input signals and amplify it as an effective signal. The differential amplifier circuit can offset common-mode interference (such as noise caused by power supply fluctuations, temperature changes, etc.) to the maximum extent, thereby improving the signal-to-noise ratio and anti-interference ability of the circuit. Since the differential amplifier circuit amplifies the difference of the input signal, it has higher accuracy and stability. Differential amplifier circuits are widely used in audio processing, detection and transmission, such as audio amplifiers, differential amplifiers, current measurement amplifiers, etc.

[0088] S123: Perform analog-to-digital conversion on at least one filtered processed signal to obtain at least one filtered voltage signal.

[0089] In this step, the analog-to-digital conversion (ADC) of the filtered signal is performed to obtain the filtered voltage signal, which is a key step in signal processing. Analog-to-digital conversion is the process of converting an analog signal (in this case, the filtered signal) into a digital signal, which is crucial for digital circuit processing and subsequent digital signal processing.

[0090] In this embodiment, an analog-to-digital converter is used to perform analog-to-digital conversion on the filtered processing signal to obtain a filtered voltage signal. The filtered processing signal is input into the analog-to-digital converter. The analog-to-digital converter samples the signal at a predetermined sampling frequency and quantizes and encodes the sampled value. Finally, the analog-to-digital converter outputs a series of digital codes, which represent the voltage value of the filtered processing signal, i.e., the filtered voltage signal. The filtered voltage signal is represented by a digital number and can be directly used for subsequent operations such as digital circuit processing, digital signal processing or storage.

[0091] Specifically, performing analog-to-digital conversion on at least one filtered processed signal to obtain at least one filtered voltage signal includes:

[0092] S1231: Perform sampling processing on at least one filtered signal to obtain at least one sampled signal.

[0093] In this step, sampling is the process of converting a continuous analog signal into a discrete signal. The sampling process is performed by a sampler, which reads the instantaneous value of the analog signal in each sampling period and stores it in a register. The choice of sampling frequency depends on the characteristics of the signal and the application requirements. It must satisfy the sampling theorem (Nyquist theorem), that is, the sampling frequency must be at least twice the highest frequency of the signal to avoid aliasing.

[0094] It should be noted that the filtered signal is an analog signal that has been filtered, and unnecessary frequency components and noise have been removed from the signal.

[0095] S1232: Perform quantization processing on at least one sampling signal to obtain at least one quantized signal.

[0096] In this step, quantization is the process of converting the sampled discrete signal into a finite number of digital values. The number of quantization bits determines the smallest signal change that the quantizer can distinguish. The higher the number of quantization bits, the smaller the quantization error, but the more storage space and processing power required.

[0097] S1233: Encode at least one quantized signal to obtain at least one filtered voltage signal.

[0098] In this step, encoding is the process of converting the quantized signal into digital code. Common encoding methods include binary encoding, Gray code encoding, and BCD encoding. The encoder is the hardware or software that completes the encoding process. Its design depends on the selected encoding method and application requirements.

[0099] S102: Collecting the freewheeling voltage of each motor winding in the brushless motor, wherein the freewheeling voltage is an interference signal generated when the electronic commutator performs phase switching on the input voltage in the motor winding.

[0100] In this step, the electronic commutator switches the voltage direction of the electronic winding in the brushless motor by opening and closing a plurality of switch elements, and the switch elements include: MOS tube, transistor, diode, capacitor, inductor, etc. When the electronic commutator switches the voltage direction of the motor winding, due to the effect of the MOS tube, transistor, diode, capacitor, and inductor, the current will not be interrupted immediately, but will continue to flow through the freewheeling path. The voltage generated in this process is the freewheeling voltage, and the magnitude and duration of the freewheeling voltage depend on the magnitude of the MOS tube, transistor, diode, capacitor, inductor, and the characteristics of the switch elements of the motor. The freewheeling voltage will affect the voltage value and / or phase of the input phase voltage, thereby affecting the operating efficiency of the brushless motor.

[0101] In a preferred embodiment, collecting the freewheeling voltage of each motor winding in the brushless motor includes:

[0102] S21: if it is determined that the speed of the brushless motor reaches a preset speed threshold and / or the running time of the brushless motor reaches a preset time threshold, collecting the element freewheeling voltage of the switching element corresponding to each motor winding in the brushless motor;

[0103] S22: Superimposing the freewheeling voltage of each switch element corresponding to the target motor winding to obtain the freewheeling voltage of the target motor winding; wherein the target motor winding is one of at least one motor winding in the brushless motor.

[0104] In this example, if the brushless motor does not reach the speed threshold and the time threshold, there is no need to adjust the commutation point of the motor winding to save computing power of the electronic commutator.

[0105] If the brushless motor reaches the speed threshold and / or time threshold, it means that the current operating condition of the brushless motor is worth consuming the computing power of the electronic commutator to adjust its commutation point. Therefore, the element freewheeling voltage of the switching element corresponding to each motor winding is collected, thereby achieving the technical effect of balancing the operating efficiency and stability of the brushless motor and the operating burden of the electronic commutator.

[0106] Since commutation of the input phase voltage in the motor winding may involve multiple switching elements, it is necessary to collect the freewheeling voltages generated by the multiple switching elements and then superimpose them to understand how much influence all the switching elements have on the input phase voltage in the motor winding when the motor winding is commutated. Therefore, accurate calculation of the real voltage of the motor winding under the influence of the switching elements is achieved.

[0107] S103: adjusting at least one state parameter of each motor winding according to the freewheeling voltage, so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively.

[0108] In this step, by adjusting the state parameters according to the freewheeling voltage, when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, so that when the rotor rotates to the commutation angle, it is exactly at the commutation point of the input phase current. At this time, the motor winding switches the voltage direction according to the commutation point, eliminating the influence of the freewheeling voltage on the operation of the brushless motor and greatly improving the rotation efficiency of the brushless motor.

[0109] In a preferred embodiment, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0110] S31: adjusting the duty cycle of the first input phase voltage according to the first freewheeling voltage to obtain a first modified voltage; wherein the first freewheeling voltage is a freewheeling voltage corresponding to the first motor winding; the first motor winding is one of at least one motor winding; and the first input phase voltage is an input phase voltage input to the first motor winding;

[0111] S32: driving the brushless motor through a first modified voltage of at least one motor winding, so that the commutation angle of the rotor on each motor winding matches the commutation point of each motor winding respectively.

[0112] In this example, since the first input phase voltage is affected by the first freewheeling voltage, the average voltage value of the first input phase voltage will decrease or increase, thereby causing the electronic commutator to commutate the voltage in the motor winding before the rotor of the brushless motor rotates to the commutation angle, or the voltage in the motor winding should have been commutated, but the rotor has already rotated beyond the commutation angle, resulting in the commutated electronic winding not only failing to provide power to drive the brushless motor, but instead providing resistance to the rotation of the brushless motor, resulting in low rotation efficiency of the brushless motor.

[0113] In this regard, this example obtains a first modified voltage by adjusting the duty cycle of the first input phase voltage according to the first freewheeling voltage to eliminate the enhancement or weakening of the first input phase voltage caused by the first freewheeling voltage, so that when the rotor rotates to the commutation angle, it is exactly at the commutation point of the input phase current, and then the electronic commutator commutates the voltage in the motor winding, thereby greatly improving the rotation efficiency of the brushless motor.

[0114] Specifically, adjusting the duty cycle of the first input phase voltage according to the first freewheeling voltage to obtain the first modified voltage includes:

[0115] S311: Obtain a first voltage value of a first freewheeling voltage;

[0116] S312: determining a first adjusted duty cycle corresponding to the first voltage value according to a preset freewheeling duty cycle mapping table; wherein the freewheeling duty cycle mapping table records at least one freewheeling voltage value and an adjusted duty cycle corresponding to each freewheeling voltage value; the adjusted duty cycle is used to define the duty cycle of the input phase voltage;

[0117] S313: adjusting the duty cycle of the first input phase voltage according to the first adjusted duty cycle to obtain a first modified voltage.

[0118] In this example, if the first freewheeling voltage has the same direction as the first input phase voltage, it means that the first freewheeling voltage will increase the voltage value of the first input phase voltage, and the adjusted duty cycle corresponding to the first freewheeling voltage in the freewheeling duty cycle mapping table will be used to reduce the duty cycle of the first input phase voltage.

[0119] If the first freewheeling voltage is in opposite directions to the first input phase voltage, it means that the first freewheeling voltage will reduce the voltage value of the first input phase voltage, and the adjusted duty cycle corresponding to the first freewheeling voltage in the freewheeling duty cycle mapping table will be used to increase the duty cycle of the first input phase voltage.

[0120] In a preferred embodiment, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0121] S33: adjusting the voltage value of the second input phase voltage according to the second freewheeling voltage to obtain a second modified voltage; wherein the second freewheeling voltage is a freewheeling voltage corresponding to the second motor winding; the second motor winding is one of the at least one motor winding; and the second input phase voltage is an input phase voltage input to the second motor winding;

[0122] S34: driving the brushless motor through the second modified voltage of at least one motor winding, so that the commutation angle of the rotor on each motor winding matches the commutation point of each motor winding respectively.

[0123] In this example, since the second input phase voltage is affected by the second freewheeling voltage, the average voltage value of the second input phase voltage will decrease or increase, which will cause the electronic commutator to commutate the voltage in the motor winding before the rotor of the brushless motor rotates to the commutation angle, or the voltage in the motor winding should be commutated, but the rotor has already rotated beyond the commutation angle, resulting in the commutated electronic winding not only failing to provide power to drive the brushless motor, but instead providing resistance to the rotation of the brushless motor, resulting in low rotation efficiency of the brushless motor.

[0124] In this regard, this example obtains a second modified voltage by adjusting the voltage value of the second input phase voltage according to the second freewheeling voltage to eliminate the enhancement or weakening of the second input phase voltage caused by the second freewheeling voltage, so that when the rotor rotates to the commutation angle, it is exactly at the commutation point of the input phase current, and then the electronic commutator commutates the voltage in the motor winding, thereby greatly improving the rotation efficiency of the brushless motor.

[0125] Specifically, adjusting the voltage value of the second input phase voltage according to the second freewheeling voltage to obtain the second modified voltage includes:

[0126] S331: Obtain a second voltage value of a second freewheeling voltage;

[0127] S332: determining a second adjustment voltage corresponding to the second voltage value according to a preset freewheeling voltage mapping table; wherein the freewheeling voltage mapping table records at least one freewheeling voltage value and an adjustment voltage corresponding to each freewheeling voltage value; and the adjustment voltage is used to define the value of the input phase voltage;

[0128] S333: adjusting the voltage value of the second input phase voltage according to the second adjustment voltage to obtain a second modified voltage.

[0129] In this example, if the second freewheeling voltage has the same direction as the second input phase voltage, it means that the second freewheeling voltage will increase the voltage value of the second input phase voltage, and the adjustment voltage corresponding to the second freewheeling voltage in the freewheeling voltage mapping table will be used to reduce the voltage value of the second input phase voltage.

[0130] If the second freewheeling voltage is in opposite directions to the second input phase voltage, it means that the second freewheeling voltage will reduce the voltage value of the second input phase voltage, and the adjustment voltage corresponding to the second freewheeling voltage in the freewheeling voltage mapping table will be used to increase the voltage value of the second input phase voltage.

[0131] In a preferred embodiment, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0132] S35: adjusting the phase of the third input phase voltage according to the third freewheeling voltage to obtain a third modified voltage; wherein the third freewheeling voltage is a freewheeling voltage corresponding to the third motor winding; and the third motor winding is one of the at least one motor winding;

[0133] S36: driving the brushless motor through the third modified voltage of at least one motor winding, so that the commutation angle of the rotor on each motor winding matches the commutation point of each motor winding respectively.

[0134] In this example, since the third input phase voltage is affected by the third freewheeling voltage, the phase of the third input phase voltage will be shifted forward or backward, which will cause the electronic commutator to commutate the voltage in the motor winding before the rotor of the brushless motor rotates to the commutation angle, or the voltage in the motor winding should be commutated, but the rotor has already rotated beyond the commutation angle, resulting in the commutated electronic winding not only failing to provide power to drive the brushless motor, but instead providing resistance to the rotation of the brushless motor, resulting in low rotation efficiency of the brushless motor.

[0135] In this regard, this example obtains a third modified voltage by adjusting the phase of the third input phase voltage according to the third freewheeling voltage, so that the third modified voltage can offset the influence of the third freewheeling voltage on the third input phase voltage in phase, thereby making the rotor exactly at the commutation point of the input phase current when it rotates to the commutation angle, and then the electronic commutator commutates the voltage in the motor winding, thereby greatly improving the rotation efficiency of the brushless motor.

[0136] Specifically, adjusting the phase of the third input phase voltage according to the third freewheeling voltage to obtain a third modified voltage includes:

[0137] S351: Obtain a third freewheeling phase of a third freewheeling voltage and a third input phase of a third input phase voltage;

[0138] S352: Determine a third adjustment phase corresponding to the third freewheeling phase and the third input phase according to a preset freewheeling phase mapping table; wherein the freewheeling phase mapping table records at least one freewheeling phase and an input phase corresponding to each freewheeling phase, and an adjustment phase corresponding to each freewheeling phase and input phase; the adjustment phase is used to adjust the phase of the input phase voltage;

[0139] S353: Adjust the phase of the third input phase voltage according to the third adjustment phase to obtain a third modified voltage.

[0140] In a preferred embodiment, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0141] S37: adjusting the commutation lead angle of the rotor to the fourth motor winding according to the fourth freewheeling voltage; wherein the fourth freewheeling voltage is a freewheeling voltage corresponding to the fourth motor winding; and the fourth motor winding is one of the at least one motor winding;

[0142] S38: Drive the brushless motor through the input phase voltage of at least one motor winding, and control the voltage direction in each motor winding according to the adjusted commutation advance angle of each motor winding, so that the commutation angle of the rotor on each motor winding matches the commutation point of each motor winding respectively.

[0143] In this example, since the fourth input phase voltage is affected by the fourth freewheeling voltage, the phase of the fourth input phase voltage may be advanced or delayed, or the voltage may increase or decrease, thereby causing the electronic commutator to commutate the voltage in the motor winding before the rotor of the brushless motor rotates to the commutation angle, or the voltage in the motor winding should have been commutated, but the rotor has already rotated beyond the commutation angle, resulting in the commutated electronic winding not only failing to provide power to drive the brushless motor, but instead providing resistance to the rotation of the brushless motor, resulting in low rotation efficiency of the brushless motor.

[0144] In this regard, this example adjusts the commutation angle of the fourth motor winding by adjusting the commutation lead angle of the rotor to the fourth motor winding according to the fourth freewheeling voltage, that is, if the rotor is not provided with a sufficiently large voltage under the influence of the fourth freewheeling voltage of the motor winding, resulting in the rotor not rotating to the commutation angle, the commutation lead angle can be reduced to make the commutation angle correspond to the commutation point. For example: when the rotor rotates to 30°, a motor control signal is generated, but due to insufficient rotor speed, within the time corresponding to the commutation lead angle originally reserved for the rotor, the rotor should have rotated to 60° at this time, but it rotated to 55°. If the motor winding is commutated at this time, it will bring resistance to the rotation of the rotor. Therefore, the method adopted in this example is to delay the time of generating the motor control signal, for example, reducing the commutation lead angle of 30° to 25°, that is, when it is detected that the rotor has rotated to 35°, the motor control signal is generated again. Then, when it is detected that the rotor has rotated to 35°, the motor control signal is generated again. Since the time required for the electronic commutator to generate the motor control signal and control the switching of the current direction of the motor winding through the switching element is constant, the time corresponding to the commutation lead angle will not change due to the change of the commutation lead angle. Furthermore, when the rotor rotates to 60°, the voltage direction of the motor winding is switched just right.

[0145] On the contrary, if the fourth freewheeling voltage of the motor winding provides an excessive voltage to the rotor, causing the rotor to rotate beyond the commutation angle, the commutation lead angle can be increased so that the commutation angle corresponds to the commutation point.

[0146] Specifically, adjusting the commutation advance angle of the rotor to the fourth motor winding according to the fourth freewheeling voltage includes:

[0147] S371: Obtain a fourth voltage value of a fourth freewheeling voltage;

[0148] S372: determining a fourth adjusted lead angle corresponding to a fourth voltage value according to a preset freewheeling lead angle mapping table; wherein the freewheeling lead angle mapping table records at least one freewheeling voltage value and an adjusted lead angle corresponding to each freewheeling voltage value;

[0149] S373: Adjust the commutation lead angle of the fourth motor winding according to the fourth adjustment lead angle.

[0150] In a preferred embodiment, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0151] S39: adjusting the duty cycle and / or voltage value of the fifth input phase voltage according to the fifth freewheeling voltage to obtain a fifth initial correction voltage; wherein the fifth freewheeling voltage is a freewheeling voltage corresponding to the fifth motor winding; the fifth motor winding is one of the at least one motor winding; and the fifth input phase voltage is an input phase voltage input to the fifth motor winding;

[0152] S310: adjusting the phase of the fifth primary modified voltage according to the fifth freewheeling voltage to obtain a fifth modified voltage; wherein the fifth freewheeling voltage is a freewheeling voltage corresponding to a fifth motor winding; and the fifth motor winding is one of the at least one motor winding;

[0153] S311: driving the brushless motor through a fifth modified voltage of at least one motor winding, so that the commutation angle of the rotor on each motor winding matches the commutation point of each motor winding respectively.

[0154] In this example, the effect of the freewheeling voltage on the speed of the brushless motor cannot be eliminated by only adjusting the phase. Also, only adjusting the duty cycle and voltage value will cause the voltage received by the motor winding to be unstable, or too high or too low, resulting in poor operating stability of the brushless motor. Therefore, by adjusting the duty cycle and / or voltage value of the input phase voltage, the brushless motor can have a relatively stable speed at the voltage level, eliminating the effect of the freewheeling voltage on the speed. At the same time, by adjusting the phase of the initial voltage, the commutation angle of the rotor on each motor winding can be matched with the commutation point, and unstable, excessive or too low voltage can be avoided.

[0155] In this embodiment, the fifth modified voltage is obtained according to the fifth freewheeling duty cycle mapping table, or the fifth modified voltage is obtained according to the fifth freewheeling voltage mapping table, or the fifth modified voltage is obtained according to the fifth freewheeling duty cycle voltage mapping table. According to the fifth freewheeling phase mapping table, the adjustment phase corresponding to the freewheeling phase of the freewheeling voltage and the input phase of the input phase voltage is determined.

[0156] The fifth freewheeling duty cycle mapping table records at least one freewheeling voltage value and an adjustment duty cycle corresponding to each freewheeling voltage value; the adjustment duty cycle is used to define the duty cycle of the input phase voltage to obtain a modified voltage;

[0157] The fifth freewheeling voltage mapping table records at least one freewheeling voltage value and an adjustment voltage corresponding to each freewheeling voltage value; the adjustment voltage is used to define the value of the input phase voltage to obtain a modified voltage;

[0158] The fifth freewheeling voltage mapping table records at least one freewheeling voltage duty cycle and voltage value, and an adjustment voltage corresponding to each freewheeling voltage duty cycle and voltage value; the adjustment voltage is used to define the value of the input phase voltage to obtain a modified voltage.

[0159] The fifth freewheeling phase mapping table records at least one freewheeling phase and an input phase corresponding to each freewheeling phase, and an adjustment phase corresponding to each freewheeling phase and input phase; the adjustment phase is used to adjust the phase of the input phase voltage to obtain a modified voltage.

[0160] In a preferred embodiment, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0161] S312: adjusting the duty cycle and / or voltage value of the sixth input phase voltage according to the sixth freewheeling voltage to obtain a sixth modified voltage; wherein the sixth freewheeling voltage is a freewheeling voltage corresponding to the sixth motor winding; the sixth motor winding is one of the at least one motor winding; and the sixth input phase voltage is an input phase voltage input to the sixth motor winding;

[0162] S313: adjusting the commutation lead angle of the rotor to the sixth motor winding according to the sixth freewheeling voltage; wherein the sixth freewheeling voltage is a freewheeling voltage corresponding to the sixth motor winding; and the sixth motor winding is one of the at least one motor winding;

[0163] S314: driving the brushless motor through the sixth modified voltage of at least one motor winding and the modified commutation advance angle of each motor winding, so that the commutation angle of the rotor on each motor winding matches the commutation point of each motor winding respectively.

[0164] In this example, the effect of the freewheeling voltage on the speed of the brushless motor cannot be eliminated by only adjusting the phase. Only adjusting the duty cycle and voltage value will cause the voltage received by the motor winding to be unstable, or too high or too low, resulting in poor operating stability of the brushless motor. Therefore, by adjusting the duty cycle and / or voltage value of the input phase voltage, the brushless motor can have a relatively stable speed at the voltage level, eliminating the effect of the freewheeling voltage on the speed. At the same time, by adjusting the commutation lead angle, the commutation angle of the rotor on each motor winding can be matched with the commutation point, and unstable, excessive or too low voltage can be avoided.

[0165] In this embodiment, the fifth modified voltage is obtained according to the fifth freewheeling duty cycle mapping table, or the fifth modified voltage is obtained according to the fifth freewheeling voltage mapping table, or the fifth modified voltage is obtained according to the fifth freewheeling duty cycle voltage mapping table. The fifth freewheeling lead angle mapping table determines the adjustment angle corresponding to the voltage value of the freewheeling voltage.

[0166] Among them, the sixth freewheeling duty cycle mapping table records at least one freewheeling voltage value and an adjustment duty cycle corresponding to the voltage value of each freewheeling voltage; the adjustment duty cycle is used to define the duty cycle of the input phase voltage to obtain a modified voltage.

[0167] The sixth freewheeling voltage mapping table records at least one freewheeling voltage value and an adjustment voltage corresponding to each freewheeling voltage value; the adjustment voltage is used to define the value of the input phase voltage to obtain a modified voltage.

[0168] The sixth freewheeling voltage mapping table records at least one freewheeling voltage duty cycle and voltage value, and an adjustment voltage corresponding to each freewheeling voltage duty cycle and voltage value; the adjustment voltage is used to define the value of the input phase voltage to obtain a modified voltage.

[0169] The sixth freewheeling lead angle mapping table records at least one freewheeling voltage value and an adjusted lead angle corresponding to each freewheeling voltage value.

[0170] In a preferred embodiment, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0171] S315: adjusting the phase of the seventh input phase voltage according to the seventh freewheeling voltage to obtain a seventh modified voltage; wherein the seventh freewheeling voltage is a freewheeling voltage corresponding to the seventh motor winding; and the seventh motor winding is one of the at least one motor winding;

[0172] S316: adjusting the commutation lead angle of the rotor to the seventh motor winding according to the seventh freewheeling voltage; wherein the seventh freewheeling voltage is a freewheeling voltage corresponding to the seventh motor winding; and the seventh motor winding is one of the at least one motor winding;

[0173] S317: driving the brushless motor through the seventh modified voltage of at least one motor winding and the modified commutation advance angle of each motor winding, so that the commutation angle of the rotor on each motor winding matches the commutation point of each motor winding respectively.

[0174] In this example, if the freewheeling voltage affects the voltage value of the input phase voltage and the phase of the input phase voltage, and if the speed requirement of the brushless motor is not high, then by adjusting the phase and the commutation advance angle, the commutation angle of the rotor on each motor winding can be ensured to match the commutation point.

[0175] In this embodiment, the adjustment phase corresponding to the freewheeling phase of the freewheeling voltage and the input phase of the input phase voltage is determined according to the seventh freewheeling phase mapping table. The seventh freewheeling lead angle mapping table determines the adjustment angle corresponding to the voltage value of the freewheeling voltage.

[0176] Among them, the seventh freewheeling phase mapping table records at least one freewheeling phase and an input phase corresponding to each freewheeling phase, and an adjustment phase corresponding to each freewheeling phase and input phase; the adjustment phase is used to adjust the phase of the input phase voltage to obtain a modified voltage.

[0177] The seventh freewheeling lead angle mapping table records at least one freewheeling voltage value and an adjusted lead angle corresponding to each freewheeling voltage value.

[0178] In a preferred embodiment, at least one state parameter of each motor winding is adjusted according to the freewheeling voltage so that when the rotor of the brushless motor rotates to the commutation angle on each motor winding, it matches the commutation point of each motor winding respectively, including:

[0179] S318: adjusting the duty cycle and / or voltage value of the eighth input phase voltage according to the eighth freewheeling voltage to obtain an eighth initially corrected voltage; wherein the eighth freewheeling voltage is a freewheeling voltage corresponding to the eighth motor winding; the eighth motor winding is one of the at least one motor winding; and the eighth input phase voltage is an input phase voltage input to the eighth motor winding;

[0180] S319: adjusting the phase of the eighth primary modified voltage according to the eighth freewheeling voltage to obtain an eighth modified voltage; wherein the eighth freewheeling voltage is a freewheeling voltage corresponding to the eighth motor winding; and the eighth motor winding is one of the at least one motor winding;

[0181] S320: adjusting the commutation lead angle of the rotor to the eighth motor winding according to the eighth freewheeling voltage; wherein the eighth freewheeling voltage is a freewheeling voltage corresponding to the eighth motor winding; and the eighth motor winding is one of the at least one motor winding;

[0182] S321: driving the brushless motor through the eighth modified voltage of at least one motor winding and the modified commutation advance angle of each motor winding, so that the commutation angle of the rotor on each motor winding matches the commutation point of each motor winding respectively.

[0183] In this example, if the freewheeling voltage affects the voltage value of the input phase voltage and the phase of the input phase voltage, if the speed requirement for the brushless motor is high, the duty cycle and / or voltage value of the input phase voltage can be adjusted to ensure that the brushless motor has a relatively stable speed at the voltage level and that the speed of the brushless motor will not be affected by the freewheeling voltage; by adjusting the phase and the commutation advance angle, the commutation angle of the rotor on each motor winding can be matched with the commutation point.

[0184] In this embodiment, the eighth modified voltage is obtained according to the eighth freewheeling duty cycle mapping table, or the eighth modified voltage is obtained according to the eighth freewheeling voltage mapping table, or the eighth modified voltage is obtained according to the eighth freewheeling duty cycle voltage mapping table. According to the eighth freewheeling phase mapping table, the adjustment phase corresponding to the freewheeling phase of the freewheeling voltage and the input phase of the input phase voltage is determined. The eighth freewheeling lead angle mapping table determines the adjustment angle corresponding to the voltage value of the freewheeling voltage.

[0185] Among them, the eighth freewheeling duty cycle mapping table records at least one freewheeling voltage value and an adjustment duty cycle corresponding to the voltage value of each freewheeling voltage; the adjustment duty cycle is used to define the duty cycle of the input phase voltage to obtain a modified voltage.

[0186] The eighth freewheeling voltage mapping table records at least one freewheeling voltage value and an adjustment voltage corresponding to each freewheeling voltage value; the adjustment voltage is used to define the value of the input phase voltage to obtain a modified voltage.

[0187] The eighth freewheeling voltage mapping table records at least one freewheeling voltage duty cycle and voltage value, and an adjustment voltage corresponding to each freewheeling voltage duty cycle and voltage value; the adjustment voltage is used to define the value of the input phase voltage to obtain a modified voltage.

[0188] The eighth freewheeling phase mapping table records at least one freewheeling phase and an input phase corresponding to each freewheeling phase, and an adjustment phase corresponding to each freewheeling phase and input phase; the adjustment phase is used to adjust the phase of the input phase voltage to obtain a modified voltage.

[0189] The eighth freewheeling lead angle mapping table records at least one freewheeling voltage value and an adjusted lead angle corresponding to each freewheeling voltage value.

[0190] Embodiment 2: The present application provides an electronic commutator, which is installed in a brushless motor, and the control method of the brushless motor described above is executed in the electronic commutator.

[0191] In this example, the electronic commutator is used to change the direction of the current so that the rotor of the motor can continue to rotate under the action of electromagnetic force.

[0192] The working principle of the electronic commutator in this example is to adjust the direction of the current in the motor coil through a control circuit. When a current passes through one coil of the motor, a magnetic field is generated, and due to electromagnetic induction, other coils also generate magnetic fields. These magnetic fields interact with each other, causing the motor to generate torque and rotate. In order to maintain continuous rotation, the direction of the current needs to be constantly changed so that the magnetic field generated by each coil is always perpendicular to the rotor magnetic field. The electronic commutator is usually composed of a group of semiconductor devices (such as transistors, diodes, etc.), which can adjust the direction of the current according to the signal of the control circuit.

[0193] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0194] Those skilled in the art will readily come to other embodiments of the present application embodiments after considering the specification and practicing the invention disclosed herein. The present application embodiments are intended to cover any variations, uses or adaptations of the present application embodiments, which follow the general principles of the present application embodiments and include common knowledge or customary technical means in the art that are not disclosed in the present application embodiments. The specification and embodiments are intended to be exemplary only, and the true scope and spirit of the present application embodiments are indicated by the following claims.

[0195] It should be understood that the embodiments of the present application are not limited to the precise structures described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the embodiments of the present application is limited only by the appended claims.

Claims

1. A method for controlling a brushless motor, characterized in that: Running in the electronic commutator of a brushless motor, including: The input phase voltage of each motor winding in the brushless motor is collected, and the state parameter of the brushless motor is obtained according to each input phase voltage; wherein the input phase voltage is a sinusoidal wave voltage input to a phase motor winding in the brushless motor; the types of the state parameters include: the duty cycle of the input phase voltage received by the motor winding, the voltage value of the input phase voltage of the motor winding, the commutation point of the motor winding and the commutation lead angle of the motor winding; the commutation point is the phase in the input phase voltage used to change the voltage direction of the motor winding; the commutation lead angle is the angle difference between the commutation angle and the real-time angle of the rotor of the brushless motor; the commutation angle is the rotation angle of the rotor when the voltage direction in the motor winding changes; the real-time angle is the rotation angle of the rotor when the motor control signal is generated; the motor control signal is an electrical signal used to instruct the electronic commutator to change the voltage direction in the motor winding; Collecting the freewheeling voltage of each motor winding in the brushless motor, wherein the freewheeling voltage is an interference signal generated by the electronic commutator when commutating the input voltage in the motor winding; adjusting at least one state parameter of each of the motor windings according to the freewheeling voltage so that when the rotor of the brushless motor rotates to a commutation angle on each of the motor windings, it matches the commutation point of each of the motor windings; Adjusting at least one state parameter of each motor winding according to the freewheeling voltage so that the rotor of the brushless motor rotates to a commutation angle on each motor winding and matches the commutation point of each motor winding respectively, including: The duty cycle of the first input phase voltage is adjusted according to the first freewheeling voltage to obtain a first modified voltage; wherein the first freewheeling voltage is a freewheeling voltage corresponding to the first motor winding; the first motor winding is one of at least one of the motor windings; the first input phase voltage is an input phase voltage input to the first motor winding; driving the brushless motor by a first modified voltage of at least one of the motor windings so that a commutation angle of the rotor on each of the motor windings matches a commutation point of each of the motor windings; The method further comprises: adjusting the duty cycle of the first input phase voltage according to the first freewheeling voltage to obtain a first modified voltage, comprising: Obtaining a first voltage value of the first freewheeling voltage; Determining a first adjusted duty cycle corresponding to the first voltage value according to a preset freewheeling duty cycle mapping table; wherein the freewheeling duty cycle mapping table records at least one freewheeling voltage value and an adjusted duty cycle corresponding to each freewheeling voltage value; the adjusted duty cycle is used to define the duty cycle of the input phase voltage; adjusting the duty cycle of the first input phase voltage according to the first adjusted duty cycle to obtain a first modified voltage; Adjusting at least one state parameter of each motor winding according to the freewheeling voltage so that the rotor of the brushless motor rotates to a commutation angle on each motor winding and matches the commutation point of each motor winding respectively, including: The voltage value of the second input phase voltage is adjusted according to the second freewheeling voltage to obtain a second modified voltage; wherein the second freewheeling voltage is a freewheeling voltage corresponding to the second motor winding; the second motor winding is one of at least one of the motor windings; the second input phase voltage is an input phase voltage input to the second motor winding; driving the brushless motor by a second modified voltage of at least one of the motor windings so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings; The method further comprises: adjusting the voltage value of the second input phase voltage according to the second freewheeling voltage to obtain a second modified voltage, comprising: Obtaining a second voltage value of the second freewheeling voltage; Determine a second adjustment voltage corresponding to the second voltage value according to a preset freewheeling voltage mapping table; wherein the freewheeling voltage mapping table records at least one freewheeling voltage value and an adjustment voltage corresponding to each freewheeling voltage value; the adjustment voltage is used to define the value of the input phase voltage; adjusting a voltage value of a second input phase voltage according to the second adjustment voltage to obtain a second modified voltage; Adjusting at least one state parameter of each motor winding according to the freewheeling voltage so that the rotor of the brushless motor rotates to a commutation angle on each motor winding and matches the commutation point of each motor winding respectively, including: The phase of the third input phase voltage is adjusted according to the third freewheeling voltage to obtain a third modified voltage; wherein the third freewheeling voltage is a freewheeling voltage corresponding to a third motor winding; and the third motor winding is one of at least one of the motor windings; driving the brushless motor by a third modified voltage of at least one of the motor windings so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings; The method further comprises: adjusting the phase of the third input phase voltage according to the third freewheeling voltage to obtain a third modified voltage, comprising: Acquire a third freewheeling phase of the third freewheeling voltage and a third input phase of the third input phase voltage; Determine a third adjustment phase corresponding to the third freewheeling phase and the third input phase according to a preset freewheeling phase mapping table; wherein the freewheeling phase mapping table records at least one freewheeling phase and an input phase corresponding to each freewheeling phase, and an adjustment phase corresponding to each freewheeling phase and input phase; the adjustment phase is used to adjust the phase of the input phase voltage; adjusting the phase of the third input phase voltage according to the third adjustment phase to obtain a third modified voltage; Adjusting at least one state parameter of each motor winding according to the freewheeling voltage so that the rotor of the brushless motor rotates to a commutation angle on each motor winding and matches the commutation point of each motor winding respectively, including: adjusting the commutation lead angle of the rotor to the fourth motor winding according to the fourth freewheeling voltage; wherein the fourth freewheeling voltage is a freewheeling voltage corresponding to the fourth motor winding; and the fourth motor winding is one of at least one of the motor windings; The brushless motor is driven by an input phase voltage of at least one of the motor windings, and the voltage direction in each of the motor windings is controlled according to the adjusted commutation advance angle of each of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings respectively; Adjusting the commutation advance angle of the rotor to the fourth motor winding according to the fourth freewheeling voltage includes: Obtaining a fourth voltage value of a fourth freewheeling voltage; Determining a fourth adjusted lead angle corresponding to a fourth voltage value according to a preset freewheeling lead angle mapping table; wherein the freewheeling lead angle mapping table records at least one freewheeling voltage value and an adjusted lead angle corresponding to each freewheeling voltage value; adjusting a commutation lead angle of a fourth motor winding according to a fourth adjustment lead angle; Adjusting the commutation lead angle of the fourth motor winding according to the fourth adjustment lead angle includes: Delaying the time of generating the motor control signal according to the fourth adjusted lead angle to reduce the commutation lead angle of the fourth motor winding; or The time for generating the motor control signal is advanced according to the fourth adjusted lead angle to increase the commutation lead angle of the fourth motor winding.

2. The control method of the brushless motor according to claim 1, characterized in that: Adjusting at least one state parameter of each motor winding according to the freewheeling voltage so that the rotor of the brushless motor rotates to a commutation angle on each motor winding and matches the commutation point of each motor winding respectively, including: The duty cycle and / or voltage value of the fifth input phase voltage is adjusted according to the fifth freewheeling voltage to obtain a fifth initial correction voltage; wherein the fifth freewheeling voltage is a freewheeling voltage corresponding to the fifth motor winding; the fifth motor winding is one of at least one of the motor windings; the fifth input phase voltage is an input phase voltage input to the fifth motor winding; The phase of the fifth initial modified voltage is adjusted according to the fifth freewheeling voltage to obtain a fifth modified voltage; wherein the fifth freewheeling voltage is a freewheeling voltage corresponding to a fifth motor winding; and the fifth motor winding is one of at least one of the motor windings; The brushless motor is driven by a fifth modified voltage of at least one of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

3. The control method of the brushless motor according to claim 1, characterized in that: Adjusting at least one state parameter of each motor winding according to the freewheeling voltage so that the rotor of the brushless motor rotates to a commutation angle on each motor winding and matches the commutation point of each motor winding respectively, including: The duty cycle and / or voltage value of the sixth input phase voltage is adjusted according to the sixth freewheeling voltage to obtain a sixth modified voltage; wherein the sixth freewheeling voltage is a freewheeling voltage corresponding to the sixth motor winding; the sixth motor winding is one of at least one of the motor windings; and the sixth input phase voltage is an input phase voltage input to the sixth motor winding; Adjusting the commutation lead angle of the rotor to the sixth motor winding according to the sixth freewheeling voltage; wherein the sixth freewheeling voltage is a freewheeling voltage corresponding to the sixth motor winding; and the sixth motor winding is one of at least one of the motor windings; The brushless motor is driven by the sixth modified voltage of at least one of the motor windings and the modified commutation advance angle of each of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

4. The control method of the brushless motor according to claim 1, characterized in that: Adjusting at least one state parameter of each motor winding according to the freewheeling voltage so that the rotor of the brushless motor rotates to a commutation angle on each motor winding and matches the commutation point of each motor winding respectively, including: The phase of the seventh input phase voltage is adjusted according to the seventh freewheeling voltage to obtain a seventh modified voltage; wherein the seventh freewheeling voltage is a freewheeling voltage corresponding to the seventh motor winding; and the seventh motor winding is one of at least one of the motor windings; adjusting the commutation lead angle of the rotor to the seventh motor winding according to the seventh freewheeling voltage; wherein the seventh freewheeling voltage is a freewheeling voltage corresponding to the seventh motor winding; and the seventh motor winding is one of at least one of the motor windings; The brushless motor is driven by the seventh modified voltage of at least one of the motor windings and the modified commutation advance angle of each of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

5. The control method of the brushless motor according to claim 1, characterized in that: Adjusting at least one state parameter of each motor winding according to the freewheeling voltage so that the rotor of the brushless motor rotates to a commutation angle on each motor winding and matches the commutation point of each motor winding respectively, including: The duty cycle and / or voltage value of the eighth input phase voltage is adjusted according to the eighth freewheeling voltage to obtain an eighth primary correction voltage; wherein the eighth freewheeling voltage is a freewheeling voltage corresponding to the eighth motor winding; the eighth motor winding is one of at least one of the motor windings; the eighth input phase voltage is an input phase voltage input to the eighth motor winding; The phase of the eighth primary modified voltage is adjusted according to the eighth freewheeling voltage to obtain an eighth modified voltage; wherein the eighth freewheeling voltage is a freewheeling voltage corresponding to the eighth motor winding; and the eighth motor winding is one of at least one of the motor windings; adjusting the commutation lead angle of the rotor to the eighth motor winding according to the eighth freewheeling voltage; wherein the eighth freewheeling voltage is a freewheeling voltage corresponding to the eighth motor winding; and the eighth motor winding is one of at least one of the motor windings; The brushless motor is driven by the eighth modified voltage of at least one of the motor windings and the modified commutation advance angle of each of the motor windings, so that the commutation angle of the rotor on each of the motor windings matches the commutation point of each of the motor windings.

6. An electronic commutator, characterized in that: Installed in a brushless motor, the electronic commutator runs the control method of the brushless motor described in any one of claims 1-5.

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