Brushless wiper motor control method, system and device based on sine and cosine position signals

Abstract

The invention discloses a method, a system and a device for controlling a brushless wiper motor based on sine and cosine position signals. The method comprises the following steps: acquiring the sine and cosine position signals of an angle sensor arranged at a rotor of the brushless wiper motor; performing arc tangent calculation on the sine and cosine position signals to obtain a real-time angle; the method comprises the following steps: acquiring a back electromotive force signal of a brushless wiper motor, calculating to obtain an estimated angle, and calculating to obtain an angle error value according to a real-time angle and the estimated angle; calculating a current angle value according to the real-time angle and the angle compensation amount; according to the method, the sine and cosine position signals of the angle sensor at the rotor of the brushless wiper motor are obtained, the back electromotive force signal of the brushless wiper motor is combined to carry out estimation angle calculation, and the accurate current angle value is finally obtained through complex compensation and correction processes. The multi-signal fusion mode effectively improves the precision of motor angle measurement, and the actual position of the brushless wiper motor rotor can be reflected more accurately.

Description

Technical Field

[0001] The present invention belongs to the field of vehicle signal processing, and in particular relates to a brushless wiper motor control method, system and device based on sine and cosine position signals. Background Art

[0002] Brushless wiper motors are a new type of motor technology that has been widely used in the automotive field in recent years. Traditional wiper motors mostly use brushed DC motors, most of which have the following problems: Wear and short life: There is mechanical friction between the brushes and commutator of the brushed motor, which causes the brushes to wear faster and need to be replaced regularly, increasing maintenance costs. Noise problem: The friction between the brush and the commutator will produce obvious noise, affecting driving comfort. Unstable speed: The speed control accuracy of traditional motors is low, and it is difficult to achieve precise speed regulation. High energy consumption: The efficiency of brushed motors is relatively low and the energy consumption is high. Compared with brushed DC motors, brushless wiper motors have improved many of the above shortcomings.

[0003] However, the measurement accuracy of the rotation of the brushless wiper motor directly affects its control performance and application effect. High-precision rotation measurement can achieve precise position control, stable speed control, and optimized dynamic performance. The measurement of the rotation of the existing brushless wiper motor mainly sets a Hall sensor on the motor stator to detect the position of the rotor magnetic pole. When the rotor rotates, the Hall sensor outputs a pulse signal. By counting the number of pulses and calculating the pulse frequency, the speed and position information of the motor can be obtained. However, the accuracy of this method is limited by the resolution of the Hall sensor. In addition, there is bound to be energy loss when the motor transmits power to the output end at the driving end. In the prior art, only the rotation of the motor is measured, and the actual rotation of the output end is lower than the detection value. This error will directly affect the rotation measurement value of the brushless wiper motor, and then affect the high-precision control of the brushless wiper motor. Therefore, it is urgent to design a brushless wiper motor control method, system and device based on sine and cosine position signals. Summary of the invention

[0004] The technical purpose of the present invention is to provide a brushless wiper motor control method, system and device based on sine and cosine position signals to measure the rotation amount of the brushless wiper motor.

[0005] To solve the above problems, the technical solution of the present invention is: A brushless wiper motor control method based on sine and cosine position signals is applied to real-time detection of the rotor position in the brushless wiper motor, comprising the following steps: Obtain the sine and cosine position signals corresponding to the motor rotor angle position at any time; Perform arc tangent calculation on the sine and cosine position signals to obtain the real-time angle of the motor; The back electromotive force signal of the brushless wiper motor is collected and calculated to obtain an estimated angle, and the real-time angle is compared with the estimated angle to calculate the angle error value; The optimized and updated angle value is calculated based on the real-time angle and the angle compensation amount; The calculation of angle compensation is: Based on the real-time angle table lookup, the sector number of the current rotor is obtained, and whether the sector sequence changes; If there is a change, the current angle base value corresponding to the current sector is read, and the previous angle base value corresponding to the previous sector is determined. The cumulative angle is calculated based on the previous angle base value and the estimated angle, and the error value between the cumulative angle and the real-time angle is obtained. The error value is determined to be abnormal based on whether it exceeds the error threshold. If it exceeds the error threshold, the estimated angle is determined to be abnormal and the angle compensation is cleared; if it does not exceed the error threshold, the angle compensation is obtained by weighted calculation based on the real-time angle and the estimated angle. If there is no change, determine whether the estimated angle satisfies or is greater than or equal to the estimated threshold; if not, jump back to the sine and cosine position signal acquisition step; if satisfied, update the real-time angle to the estimated angle, and calculate the angle compensation amount based on the angle error value and the estimated angle.

[0006] Further preferably, the obtained sine and cosine position signals are low-pass filtered and normalized before arc tangent calculation, and the calculation formula for arc tangent calculation is: ; in, is a sinusoidal signal, is a cosine signal.

[0007] The back electromotive force signal at the stator of the brushless wiper motor is collected, and the average rotation time of 60° is calculated based on the time of 360° rotation of the stator of the brushless wiper motor in one electrical cycle, and the angular velocity of the rotor is calculated based on the average rotation time of 60°, and the estimated angle is obtained through the angular velocity calculation of the rotor; The angle error value is calculated as the estimated angle minus the actual angle.

[0008] Specifically, the sector in which the rotor rotates is divided into 6 sectors, each sector is 60° apart, the relationship between each sector and the angle is marked in advance, and the sector number of the rotor at the real-time angle is obtained by looking up the angle table.

[0009] After determining that the sector has changed, the cumulative angle is calculated by adding the previous angle base value to the estimated angle, and the error value is calculated by subtracting the real-time angle from the cumulative angle, and it is determined whether the error value exceeds the error threshold, where the error threshold is set to 30°; If the error threshold is exceeded, the brushless wiper motor is determined to be fluctuating, the estimated angle is abnormal data, and the angle compensation is cleared, and the current angle value is equal to the real-time angle; If the error threshold is not exceeded, the angle compensation is calculated by subtracting the weighted estimated angle from the real-time angle to obtain the current angle value.

[0010] Specifically, after determining that the sector has not changed, further determine whether the estimated angle satisfies or is greater than or equal to an estimated threshold; wherein the estimation threshold selection range is 60 to 180°; If not satisfied, jump back to the sine and cosine position signal acquisition step; If the conditions are met, the real-time angle is forced to be updated, the estimated angle is identified as the rotor position, and the angle compensation is calculated. The angle compensation is calculated by subtracting the angle error value from the estimated angle and then multiplying it by the gain coefficient.

[0011] A brushless wiper motor control system based on sine-cosine position signals is adapted to the above-mentioned brushless wiper motor control method based on sine-cosine position signals, comprising: Interface module, main control module, drive circuit, detection module and brushless wiper motor; The interface module is electrically connected to the main control module, and includes a power supply interface, a communication interface, and an angle detection interface. The interface module provides power support to the main control module, the drive circuit, and the brushless wiper motor via the power supply interface, transmits control instructions to the main control module via the communication interface, and transmits angle detection signals to the main control module via the angle detection interface; wherein the angle detection signals include sine and cosine position signals of an angle sensor at a rotor of the brushless wiper motor, and analog signals of an angle sensor at a gear of the brushless wiper motor; The main control module is also electrically connected to the drive circuit, and is configured to send a control signal to the drive circuit according to the control instruction, and receive an angle detection signal to perform real-time detection of the rotation angle of the rotor and gear of the brushless wiper motor; The driving circuit is electrically connected to the brushless wiper motor and is configured to receive a control signal to drive the brushless wiper motor to rotate; The detection module is electrically connected to the main control module and the driving circuit respectively, and is configured to detect and transmit a motor current detection signal and a motor temperature detection signal to the main control module.

[0012] Specifically, the main control module includes a power module, a boost unit, a clock unit, a PWM generator, a wake-up unit, a communication unit, a storage unit, a microcontroller, a transceiver, an analog-to-digital converter, and a drive protection unit; The power module is electrically connected to the power supply interface and is configured to provide power management for the main control module; The boost unit is configured to provide a high voltage to the gate of the H-bridge high-side MOS tube of the driving circuit; The clock unit is configured to provide a clock signal to the main control module; The PWM generator is configured to generate a PWM signal to be input to the driving circuit; The wake-up unit is configured to wake up the microcontroller from a low power mode to a normal working mode; The transceiver is configured to receive control instructions; The communication unit is configured to perform signal processing on the received control instruction and transmit the signal to the microcontroller; The storage unit is configured to store relevant instructions for execution by the microcontroller; The microcontroller is configured to control the PWM generator according to the control command, the motor current detection signal, the motor temperature detection signal and the angle detection signal to adjust the operation of the brushless wiper motor; The analog-to-digital converter is configured to convert the motor current detection signal, the motor temperature detection signal and the angle detection signal into digital signals recognizable by the microcontroller; The driving protection unit is configured to achieve over-current protection by turning off the MOS tube in the driving circuit.

[0013] A brushless wiper motor control device based on sine-cosine position signals, adapted to the brushless wiper motor control method based on sine-cosine position signals as described above; The brushless wiper motor comprises: an outer shell, a driving mechanism and an output mechanism, wherein the driving mechanism and the output mechanism are arranged in the outer shell; a transmission rod is arranged in the driving mechanism, one end of the transmission rod extends into the driving mechanism and realizes transmission connection, and the other end of the transmission rod is transmission connected with the output mechanism; A measuring assembly connected to the transmission rod is also provided, the measuring assembly includes a magnetic ring and a Hall sensor, the magnetic ring is sleeved on the transmission rod and arranged close to one side of the driving mechanism, the Hall sensor is arranged close to the magnetic ring, the Hall sensor and the magnetic ring cooperate with each other, and are configured to measure the rotation angle of the transmission rod in real time to generate a sine and cosine position signal for measuring the rotation of the brushless wiper motor rotor; An output rod, a rotating gear and an angle sensor are arranged in the output mechanism. The rotating gear is in transmission connection with the transmission rod, and the rotating gear is sleeved on the output rod. The angle sensor is configured to measure the rotation angle of the rotating gear in real time.

[0014] Further preferably, the driving mechanism further comprises a stator, a rotor, an iron core and a magnet; The iron core is connected to the transmission rod; A first circular through hole is opened at the center of the rotor, and the iron core is arranged in the first circular through hole; The magnets are wrapped around and fit on the side of the rotor; The stator is surrounded and fitted on the inner wall of the outer shell and is arranged corresponding to the magnet.

[0015] Specifically, a mounting frame is provided inside the outer shell and on the path of the transmission rod, the mounting frame is fixed inside the outer shell, and the mounting frame is configured to install a Hall sensor circuit board; a Hall sensor is installed on the Hall sensor circuit board, and an inwardly recessed notch is opened on the top of the Hall sensor circuit board, and the transmission rod passes through the notch for transmission connection with the output mechanism; the magnetic ring is sleeved on the transmission rod, located between the Hall sensor circuit board and the iron core, and is arranged close to the Hall sensor circuit board.

[0016] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art: The present invention obtains the sine and cosine position signals of the angle sensor at the rotor of the brushless wiper motor, and estimates the angle calculation in combination with the back-EMF signal of the brushless wiper motor. After a complex compensation and correction process, the accurate current angle value is finally obtained. This multi-signal fusion method effectively improves the accuracy of motor angle measurement and can more accurately reflect the actual position of the brushless wiper motor rotor.

[0017] The present invention not only provides a rotation measurement method, but also designs a complete rotation measurement system and device, covering multiple key parts such as interface module, main control module, drive circuit, detection module, etc., realizing integrated integration from signal acquisition and processing to motor drive control, which is convenient for installation and deployment in practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the following detailed description of the preferred embodiment.The drawings are only for the purpose of illustrating the preferred embodiments and are not to be construed as limiting the invention.

[0019] Figure 1 A schematic flow chart of a brushless wiper motor control method based on sine and cosine position signals of the present invention; Figure 2 It is a structural block diagram of a brushless wiper motor control system based on sine and cosine position signals of the present invention; Figure 3 The present invention is a schematic structural diagram of a brushless wiper motor control device based on sine and cosine position signals.

[0020] Description of Reference Numerals 1: Hall sensor; 2: Magnetic ring; 3: Mounting frame; 4: Stator; 5: Rotor; 6: Magnet; 7: Transmission rod; 8: Output rod; 9: Rotating gear. DETAILED DESCRIPTION

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0022] In order to simplify the drawings, only the parts related to the present invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0023] The following is a further detailed description of a brushless wiper motor control method, system and device based on sine and cosine position signals proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description and claims.

[0024] Example 1 See also Figure 1 This embodiment provides a brushless wiper motor control method based on sine and cosine position signals, comprising the following steps: First, obtain the signal of the angle sensor arranged at the rotor of the brushless wiper motor. In this embodiment, the angle sensor adopts a Hall sensor, and a magnetic ring corresponding to the Hall sensor is arranged near the brushless wiper motor. The motor and the magnetic ring cooperate with each other, and the magnetic field changes when the motor rotates. The changing magnetic field is detected in real time by the Hall sensor, and then the signal of the Hall sensor is collected in real time, so that two signals can be obtained, namely a sine signal and a cosine signal.

[0025] After sampling, the obtained sine and cosine position signals will be low-pass filtered and normalized for preprocessing. After preprocessing, the inverse tangent calculation will be performed to obtain the real-time angle. The calculation formula for the inverse tangent calculation is: ; in, is a sinusoidal signal, is a cosine signal.

[0026] Then, the angular velocity, estimated angle and angular error value are calculated respectively.

[0027] Specifically, the back electromotive force signal of the brushless wiper motor is obtained by sampling the suspended phase line voltage through hardware, and the average rotation time of 60° is calculated based on the time of 360° rotation of the stator of the brushless wiper motor, so as to achieve the filtering effect. The angular velocity of the rotor is then calculated based on the average rotation time of 60°, and the estimated angle is obtained by integrating the angular velocity of the rotor. The calculation formula is: ; in, represents the angular acceleration, represents the angular velocity, Indicates time.

[0028] The angle error is calculated by subtracting the actual angle from the estimated angle.

[0029] Then, the current angle value is calculated based on the real-time angle and the angle compensation amount, and the current angle value is the final value to be solved in this embodiment. The calculation of the angle compensation amount is now explained: Based on the real-time angle, the sector number of the current rotor is obtained by angle table lookup, and it is determined whether the sector has undergone a sequence change. Among them, the sectors rotated by the rotor are artificially divided into 6 blocks, each sector is 60° apart, and the relationship between each sector and the angle is marked in advance. After obtaining the real-time angle, the sector number of the rotor can be obtained by angle table lookup.

[0030] If the table is checked and it is found that the sector has changed, the current angle base value corresponding to the current sector is read, and the previous angle base value corresponding to the previous sector is determined, wherein each sector corresponds to an angle base value, and in this embodiment, the angle base values ​​are 30°, 90°, 150°, 210°, 270°, and 330°, respectively. The cumulative angle is calculated based on the previous angle base value and the estimated angle. The cumulative angle is calculated by adding the previous angle base value to the estimated angle. The cumulative angle ranges from 0 to 360°, and the estimated angle is theoretically 60°. Further, the error value between the cumulative angle and the real-time angle is obtained, and whether the error value exceeds the error threshold is determined, wherein the error value is calculated by subtracting the real-time angle from the cumulative angle, and the error threshold is set to 30°. If the error threshold is exceeded, it means that the surface motor position has a large fluctuation, and the estimated angle is determined to be abnormal and unreliable, and the angle compensation amount is cleared. At this time, the current angle value is equal to the real-time angle. If the error threshold is not exceeded, the angle compensation is obtained by weighted calculation based on the real-time angle and the estimated angle. Specifically, compensation angle = (real-time angle * A + estimated angle * B) / (A + B), where A and B are artificially assigned weights. At this time, the current angle value is equal to the real-time angle plus the angle compensation obtained in this step.

[0031] If the table query finds that the sector has not changed, it is further determined whether the estimated angle satisfies or is greater than or equal to the estimated threshold; wherein the estimated threshold is equal to 60° + A, and the selection range of A is 0 to 2 times of 60°. If not satisfied, jump back to the sine and cosine position signal acquisition step. If satisfied, the real-time angle is forced to be updated, and the estimated angle is identified as the rotor position. It can be understood that when the sensor angle has not changed for a long time, the current rotor position is forced to be the estimated angle to promote the motor to commutate. Then, the estimated angle is subtracted from the angle error value, and then multiplied by the gain coefficient to calculate the angle compensation amount, where the gain coefficient is an artificially assigned value, which is 0.5 in this embodiment.

[0032] Example 2 See also Figure 2 This embodiment provides a rotation measurement system for a brushless wiper motor, which is adapted to a brushless wiper motor control method based on sine and cosine position signals as in Embodiment 1, and mainly includes an interface module, a main control module, a drive circuit, a detection module and a brushless wiper motor.

[0033] Among them, the interface module is electrically connected to the main control module, and the interface module includes a power supply interface, a communication interface and an angle detection interface. Specifically, the external power supply current will provide power support to the main control module, the drive circuit and the brushless wiper motor through the power supply interface. Among them, the interface KL30 is connected to the positive pole of the power supply, and the interface KL31 is connected to the negative pole of the power supply. After the power supply current passes through the interface KL30, it is filtered by the filter circuit, and the anti-reverse circuit enters the main control module and the energy storage capacitor respectively, and the power supply current enters the drive circuit after the energy storage capacitor. Interface KL31 is connected to the negative pole of the power supply and grounded. The external control instructions are input to the main control module through the CAN communication interface and another filter circuit in turn. The sine and cosine position signals collected by the Hall sensor in Example 1 are transmitted to the main control module through the angle detection interface (angle detection b). The angle detection a transmits the analog signal of the angle sensor set at the gear of the brushless wiper motor to the main control module, and the angle sensor can identify the rotation angle of the gear.

[0034] Furthermore, the main control module is also electrically connected to the drive circuit, and can send control signals to the drive circuit according to the received control instructions, and receive angle detection signals to perform real-time detection of the rotation angles of the rotor and gears of the brushless wiper motor. Specifically, the main control module includes a power module, a boost unit, a clock unit, a PWM generator, a wake-up unit, a communication unit, a storage unit, a microcontroller, a transceiver, an analog-to-digital converter, and a drive protection unit.

[0035] The power current mentioned above will enter the power module in the main control module, which can provide power management for the entire main control module. The boost unit is used to provide a high voltage to the gate of the MOS tube in the anti-reverse circuit, and also to provide a high voltage to the gate of the H-bridge high-side MOS tube of the drive circuit. The clock unit is used to provide a clock signal to the main control module. The PWM generator is used to generate a PWM signal and input it to the drive circuit. The wake-up unit is used to wake up the microcontroller from a low power mode to a normal working mode according to the control instruction. The transceiver is used to receive the control instruction input from the CAN interface. The communication unit is used to perform signal processing on the received control instruction and pass it to the microcontroller. The storage unit stores relevant instructions for the microcontroller to run. The microcontroller controls the PWM generator according to the control instruction, the motor current detection signal, the motor temperature detection signal and the angle detection signal to adjust the operation of the brushless wiper motor, wherein the microcontroller can execute a brushless wiper motor control method based on a sine-cosine position signal as described in Example 1. The analog-to-digital converter converts the motor current detection signal, the motor temperature detection signal and the angle detection signal into digital signals recognizable by the microcontroller, wherein the motor current detection signal is obtained through the current detection circuit of the detection module, and the motor temperature detection signal is obtained through the temperature detection circuit of the detection module. The drive protection unit is used to achieve overcurrent protection by shutting down the MOS tube in the drive circuit. Specifically, overcurrent detection is performed on the upper MOS or lower MOS of the H-bridge of the drive circuit, and the voltage drop of the MOS tube VDS is set and detected to determine whether the MOS tube has overcurrent. If it exceeds the preset threshold, the system determines that it is overcurrent and shuts down the corresponding channel MOS. If it does not exceed the threshold, the system works normally. The drive circuit is electrically connected to the brushless wiper motor, and drives the brushless wiper motor to rotate according to the received control signal.

[0036] Example 3 See also Figure 3 The present embodiment provides a rotation measurement device for a brushless wiper motor, which is adapted to the brushless wiper motor control method based on sine and cosine position signals as in Embodiment 1.

[0037] From a structural point of view, the brushless wiper motor includes: an outer shell, a driving mechanism and an output mechanism, and the driving mechanism and the output mechanism are arranged in the outer shell. Figure 3 As shown, part of the outer shell is hidden so that the internal structure can be seen intuitively.

[0038] See also Figure 3, the driving mechanism is now described: a transmission rod 7 is arranged in the driving mechanism, one end of the transmission rod 7 extends into the driving mechanism and realizes a transmission connection, and the other end of the transmission rod 7 is in transmission connection with the output mechanism. The measuring assembly is connected to the transmission rod 7, and the measuring assembly includes a magnetic ring 2 and a Hall sensor 1. The magnetic ring 2 is sleeved on the transmission rod 7 and arranged close to one side of the driving mechanism, and the Hall sensor 1 is arranged close to the magnetic ring 2. The Hall sensor 1 cooperates with the magnetic ring 2 to measure the rotation angle of the transmission rod 7 (equivalent to the rotation angle of the rotor 5) in real time, so as to generate a sine-cosine position signal for measuring the rotation of the brushless wiper motor rotor 5, that is, the sine-cosine position signal to be collected in Example 1.

[0039] Preferably, the driving mechanism further includes a stator 4, a rotor 5, an iron core and a magnet 6. The rotor 5 is arranged inside the driving mechanism, a first circular through hole is opened at the center of the rotor 5, the iron core is arranged in the first circular through hole, and one end of the iron core is connected to the transmission rod 7. The magnet 6 surrounds and fits the side of the rotor 5, and the stator 4 surrounds and fits on the inner wall of the outer shell and is arranged corresponding to the magnet 6. One end of the transmission rod 7 extends into the interior of the driving mechanism and is transmission-connected to the iron core, and the other end of the transmission rod 7 is transmission-connected to the output mechanism. The stator 4 of the driving mechanism is a coil winding armature, and the magnet 6 and the rotor 5 form a permanent magnet rotor 5. During implementation, the rotor 5 drives the iron core to make the transmission rod 7 rotate around its own axis.

[0040] See also Figure 3 Furthermore, a mounting frame 3 is provided in the outer shell and on the path of the transmission rod 7. The mounting frame 3 is fixed inside the outer shell. The mounting frame 3 is used to install the circuit board of the Hall sensor 1, and the Hall sensor 1 is installed on the circuit board. The top of the circuit board is provided with an inwardly recessed notch, and the transmission rod 7 passes through the notch and is connected to the output mechanism. Specifically, the magnetic ring 2 is sleeved on the transmission rod 7, located between the circuit board and the iron core, and is arranged close to the circuit board.

[0041] An output rod 8, a rotating gear 9 and an angle sensor are provided in the output mechanism. The rotating gear 9 is connected to the transmission rod 7 in transmission connection. The rotating gear 9 is sleeved on the output rod 8. The angle sensor is provided at one end of the transmission rod 7 for real-time measurement of the rotation angle of the rotating gear 9. The signal collected by the angle sensor is input to the main control module via the angle detection a in Example 2.

[0042] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A brushless wiper motor control method based on sine and cosine position signals, applied to real-time detection of rotor position in a brushless wiper motor, characterized in that: The steps include: Obtain the sine and cosine position signals corresponding to the motor rotor angle position at any time; Performing arc tangent calculation on the sine and cosine position signals to obtain the real-time angle of the motor; An estimated angle is obtained by collecting a back electromotive force signal of a brushless wiper motor and calculating the estimated angle, and the real-time angle is compared with the estimated angle to calculate an angle error value; Calculate an optimized and updated angle value based on the real-time angle and the angle compensation amount; The angle compensation amount is calculated as follows: Obtaining the sector number of the current rotor based on the real-time angle table lookup, and determining whether the sector has undergone sequence changes; If there is a change, the current angle base value corresponding to the current sector is read, and the previous angle base value corresponding to the previous sector is determined, the cumulative angle is calculated according to the previous angle base value and the estimated angle, the error value between the cumulative angle and the real-time angle is obtained, and whether the error value exceeds an error threshold is determined. If it exceeds the error threshold, the estimated angle is determined to be abnormal, and the angle compensation amount is cleared; if it does not exceed the error threshold, a weighted calculation is performed according to the real-time angle and the estimated angle to obtain the angle compensation amount; If there is no change, determine whether the estimated angle satisfies or is greater than or equal to the estimation threshold; if not, jump back to the sine and cosine position signal acquisition step; if satisfied, update the real-time angle to the estimated angle, and calculate the angle compensation amount based on the angle error value and the estimated angle.

2. The brushless wiper motor control method based on sine and cosine position signals according to claim 1, characterized in that: The obtained sine and cosine position signals are low-pass filtered and normalized before arc tangent calculation. The calculation formula for arc tangent calculation is: ； in, is a sinusoidal signal, is a cosine signal.

3. The brushless wiper motor control method based on sine and cosine position signals according to claim 1, characterized in that: By collecting the back electromotive force signal at the stator of the brushless wiper motor, the average rotation time of 60° is calculated based on the time of 360° rotation of the stator of the brushless wiper motor, the angular velocity of the rotor is calculated based on the average rotation time of 60°, and the estimated angle is obtained through the angular velocity calculation of the rotor; The angle error value is calculated by subtracting the real-time angle from the estimated angle.

4. The brushless wiper motor control method based on sine and cosine position signals according to claim 1, characterized in that: The sector in which the rotor rotates is divided into 6 sectors, each sector is 60° apart, the relationship between each sector and the angle is marked in advance, and the sector number of the rotor at the real-time angle is obtained by looking up the angle table.

5. The brushless wiper motor control method based on sine and cosine position signals according to claim 1, characterized in that: After determining that the sector has changed, the cumulative angle is calculated by adding the previous angle base value to the estimated angle, the error value is calculated by subtracting the real-time angle from the cumulative angle, and it is determined whether the error value exceeds the error threshold, wherein the error threshold is set to 30°; If the error threshold is exceeded, it is determined that the brushless wiper motor fluctuates, the estimated angle is abnormal data, and the angle compensation amount is cleared, and the current angle value is equal to the real-time angle; If the error threshold is not exceeded, the angle compensation amount is calculated by subtracting the estimated angle after weighting from the real-time angle to obtain the current angle value.

6. The brushless wiper motor control method based on sine and cosine position signals according to claim 1, characterized in that: After determining that the sector has not changed, further determining whether the estimated angle satisfies or is greater than or equal to an estimated threshold; wherein the estimation threshold selection range is 60 to 180°; If not satisfied, jump back to the step of acquiring the sine and cosine position signals; If the conditions are met, the real-time angle is forced to be updated, the estimated angle is identified as the rotor position, and the angle compensation is calculated. The angle compensation is calculated by subtracting the angle error value from the estimated angle and then multiplying the result by a gain coefficient.

7. A brushless wiper motor control system based on sine-cosine position signals, adapted to the brushless wiper motor control method based on sine-cosine position signals as claimed in any one of claims 1 to 6, characterized in that: include: Interface module, main control module, drive circuit, detection module and brushless wiper motor; The interface module is electrically connected to the main control module, and the interface module includes a power supply interface, a communication interface, and an angle detection interface. The interface module provides power support to the main control module, the drive circuit, and the brushless wiper motor via the power supply interface, transmits control instructions to the main control module via the communication interface, and transmits an angle detection signal to the main control module via the angle detection interface; wherein the angle detection signal includes a sine and cosine position signal of an angle sensor at a rotor of the brushless wiper motor, and an analog signal of an angle sensor at a gear of the brushless wiper motor; The main control module is also electrically connected to the drive circuit, and is configured to send a control signal to the drive circuit according to a control instruction, and receive an angle detection signal to perform real-time detection of the rotation angle of the rotor and gear of the brushless wiper motor; The driving circuit is electrically connected to the brushless wiper motor and is configured to receive a control signal to drive the brushless wiper motor to rotate; The detection module is electrically connected to the main control module and the driving circuit respectively, and is configured to detect and transmit a motor current detection signal and a motor temperature detection signal to the main control module.

8. The brushless wiper motor control system based on sine and cosine position signals according to claim 7, characterized in that: The main control module includes a power module, a boost unit, a clock unit, a PWM generator, a wake-up unit, a communication unit, a storage unit, a microcontroller, a transceiver, an analog-to-digital converter and a drive protection unit; The power supply module is electrically connected to the power supply interface and is configured to provide power management for the main control module; The boost unit is configured to provide a high voltage to the gate of the H-bridge high-side MOS tube of the driving circuit; The clock unit is configured to provide a clock signal to the main control module; The PWM generator is configured to generate a PWM signal to be input to the driving circuit; The wake-up unit is configured to wake up the microcontroller from a low power consumption mode to a normal working mode; The transceiver is configured to receive a control instruction; The communication unit is configured to perform signal processing on the received control instruction and transmit the signal to the microcontroller; The storage unit is configured to store relevant instructions for the microcontroller to execute; The microcontroller is configured to control the PWM generator according to the control instruction, the motor current detection signal, the motor temperature detection signal and the angle detection signal to adjust the operation of the brushless wiper motor; The analog-to-digital converter is configured to convert the motor current detection signal, the motor temperature detection signal and the angle detection signal into digital signals recognizable by the microcontroller; The driving protection unit is configured to achieve over-current protection by turning off the MOS tube in the driving circuit.

9. A brushless wiper motor control device based on sine-cosine position signals, adapted to the brushless wiper motor control method based on sine-cosine position signals as claimed in any one of claims 1 to 6, characterized in that: The brushless wiper motor comprises: an outer shell, a driving mechanism and an output mechanism, wherein the driving mechanism and the output mechanism are arranged in the outer shell; a transmission rod is arranged in the driving mechanism, one end of the transmission rod extends into the driving mechanism and realizes transmission connection, and the other end of the transmission rod is transmission connected with the output mechanism; A measuring assembly connected to the transmission rod is also provided, the measuring assembly includes a magnetic ring and a Hall sensor, the magnetic ring is provided on the transmission rod and is arranged close to one side of the driving mechanism, the Hall sensor is arranged close to the magnetic ring, the Hall sensor cooperates with the magnetic ring, and is configured to measure the rotation angle of the transmission rod in real time to generate a sine and cosine position signal for measuring the rotation of the brushless wiper motor rotor; The output mechanism is provided with an output rod, a rotating gear and an angle sensor. The rotating gear is in transmission connection with the transmission rod, and the rotating gear is sleeved on the output rod. The angle sensor is configured to measure the rotation angle of the rotating gear in real time.

10. The brushless wiper motor control device based on sine and cosine position signals according to claim 9, characterized in that: The driving mechanism also includes a stator, a rotor, an iron core and a magnet; The iron core is connected to the transmission rod; A first circular through hole is opened at the center of the rotor, and the iron core is arranged in the first circular through hole; The magnet surrounds and fits on the side surface of the rotor; The stator is circumferentially attached to the inner wall of the outer shell and is arranged corresponding to the magnet.

11. The brushless wiper motor control device based on sine and cosine position signals according to claim 10, characterized in that: A mounting frame is provided in the outer shell and on the path of the transmission rod, the mounting frame is fixed to the inside of the outer shell, and the mounting frame is configured to install a Hall sensor circuit board; the Hall sensor is installed on the Hall sensor circuit board, and an inwardly recessed notch is provided on the top of the Hall sensor circuit board, and the transmission rod passes through the notch to be transmission-connected to the output mechanism; the magnetic ring is sleeved on the transmission rod, located between the Hall sensor circuit board and the iron core, and is arranged close to the Hall sensor circuit board.

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