A method, device, system, and joint module for detecting the position of an electric motor rotor.

Abstract

This application discloses a method, apparatus, system, and joint module for detecting the position of a motor rotor, relating to the field of motor control technology. It acquires the voltage values ​​of each Hall sensor. The Hall sensors are symmetrically distributed on the drive board of the motor under test, saving axial space and ensuring the parallelism between the drive board and the motor rotor magnets. In the circumferential direction, each Hall sensor is deployed between adjacent stator slots with opposite winding currents, canceling the influence of the armature magnetic field generated by the current on the Hall sensors. In the radial direction, each Hall sensor is separated from the motor rotor magnet by a set distance. The voltage values ​​of each Hall sensor are converted into Gaussian values ​​of magnetic field strength. The peak value of each Gaussian magnetic field strength is adjusted according to a peak normalization method. Based on the adjusted peak value of the Gaussian magnetic field strength and the phase difference value of each Hall sensor, the rotor electrical angle of the motor under test can be determined. This method reduces detection costs while ensuring the accuracy of motor rotor rotation position detection.

Description

Technical Field

[0001] This application relates to the field of motor control technology, and in particular to a method, device, system and joint module for detecting the position of a motor rotor. Background Technology

[0002] With the continuous development of humanoid robots, the use of joint modules is increasing. This also places demands on joint modules to achieve smaller size and lower cost. Joint modules are typically highly integrated with frameless motors, reducers, brakes, and position sensors. In the application of frameless motors, it is necessary to obtain the rotational position of the motor rotor in real time, generate a variable current based on the rotor's rotational position, and then generate a variable electromagnetic force through an electromagnetic coil to enable the motor rotor to float stably.

[0003] Current mainstream solutions use photoelectric encoders, rotary transformers, or magnetic encoders to detect the position of the motor rotor. While these solutions offer high accuracy, they often require additional code disks and suffer from weak interference resistance and high cost.

[0004] It is evident that how to reduce testing costs while ensuring the accuracy of motor rotor rotation position detection is a problem that needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this application is to provide a method, device, system, and joint module for detecting the position of a motor rotor, which can solve the problems of weak anti-interference and high cost in the position detection of motor rotors.

[0006] This application provides a method for detecting the position of a motor rotor, including:

[0007] The voltage values ​​of each Hall sensor are obtained; wherein, each Hall sensor is symmetrically distributed on the drive board of the motor under test, and each Hall sensor is deployed in the middle of adjacent stator slots with opposite winding currents in the circumferential direction, and each Hall sensor is separated from the motor rotor magnet by a set distance in the radial direction.

[0008] The voltage values ​​of each Hall sensor are converted into Gaussian values ​​of magnetic field strength;

[0009] Adjust the peak value of each magnetic field strength Gaussian value according to the peak value normalization method;

[0010] The rotor electrical angle of the motor under test is determined based on the peak value of the adjusted Gaussian magnetic field strength and the phase difference value of each Hall sensor.

[0011] On the one hand, regarding the determination of the circumferential deployment positions of each Hall sensor, the methods include:

[0012] Obtain the number of slots, number of pole pairs, and winding method of the motor under test;

[0013] The circumferential deployment position of each Hall sensor is determined based on the number of slots, number of pole pairs, winding method of the motor under test, and the total number of Hall sensors.

[0014] On the one hand, before determining the circumferential deployment position of each Hall sensor based on the number of slots, number of pole pairs, winding method, and total number of Hall sensors of the motor under test, the following steps are also included:

[0015] Determine whether the winding method of the motor under test satisfies the condition that the currents of adjacent stator windings are opposite;

[0016] If the winding method of the motor under test satisfies that the adjacent stator winding currents are opposite, determine whether the number of slots of the motor under test is an integer multiple of the total number of Hall sensors.

[0017] If the number of slots of the motor under test is an integer multiple of the total number of Hall sensors, determine whether the number of pole pairs of the motor under test meets the phase requirements.

[0018] If the number of pole pairs of the motor under test meets the phase requirements, the operation of determining the circumferential deployment position of each Hall sensor is performed based on the number of slots, number of pole pairs, winding method, and total number of Hall sensors of the motor under test.

[0019] On the one hand, the method for determining the set distance between each Hall sensor and the motor rotor magnet includes:

[0020] The magnetic field strength of the target Hall sensor and the motor rotor magnet at different distances was determined using magnetic field simulation; where the target Hall sensor is any one of the Hall sensors.

[0021] The distance corresponding to the magnetic field strength falling within the set strength range is taken as the set distance.

[0022] On the one hand, after obtaining the number of slots, number of pole pairs, and winding method of the motor under test, it also includes:

[0023] The included angle between adjacent Hall sensors is determined based on the number of slots in the motor under test and the total number of Hall sensors.

[0024] The phase difference between adjacent Hall sensors is determined based on the number of pole pairs and the angle between adjacent Hall sensors.

[0025] On the one hand, based on the number of slots in the motor under test and the total number of Hall sensors, the included angle between adjacent Hall sensors is determined, including:

[0026] Perform a division operation between the circumferential angle and the number of slots of the motor under test to obtain the included angle between adjacent positioning pins; perform a division operation between the number of slots of the motor under test and the total number of Hall sensors to obtain the upper limit value of the electrical angle.

[0027] Even numbers less than or equal to the upper limit of electrical angle are used as the number of electrical angles between adjacent Hall sensors;

[0028] The product of the angle between adjacent positioning pins and the number of electrical angles between adjacent Hall sensors is taken as the angle between adjacent Hall sensors.

[0029] On the one hand, based on the number of pole pairs and the angle between adjacent Hall sensors, the phase difference between adjacent Hall sensors is determined, including:

[0030] The phase difference calculation formula is used to analyze the number of pole pairs and the angle between adjacent Hall sensors to determine the phase difference between adjacent Hall sensors. The phase difference calculation formula is as follows:

[0031] ;

[0032] in, The value represents the phase difference between adjacent Hall sensors, α represents the angle between adjacent Hall sensors, A represents the number of electrical angles between adjacent Hall sensors, and P represents the number of pole pairs.

[0033] On the one hand, the peak values ​​of each magnetic field strength Gaussian value are adjusted according to the peak value normalization method, including:

[0034] The Gaussian values ​​of the magnetic field strength of each Hall sensor were obtained as multiple peak values ​​of the motor under test were obtained during multiple revolutions.

[0035] The peak values ​​corresponding to the Hall sensors with symmetrical relationships are normalized to determine the normalized peak value corresponding to the Hall sensors with symmetrical relationships.

[0036] On the one hand, based on the peak value of the adjusted Gaussian magnetic field strength and the phase difference values ​​of each Hall sensor, the rotor electrical angle of the motor under test is determined, including:

[0037] With a total of six Hall sensors, the sinusoidal signal of each Hall sensor is determined based on the peak value of the adjusted magnetic field strength Gaussian value and the phase difference of each Hall sensor.

[0038] Based on the principle of symmetry, the sinusoidal signals from the six Hall sensors are converted into three sinusoidal signals—a first sinusoidal signal, a second sinusoidal signal, and a third sinusoidal signal—that are 60 degrees out of phase.

[0039] Convert the first, second, and third sine signals into the fourth and fifth sine signals;

[0040] The fourth and fifth sine signals are processed by arctangent to determine the rotor electrical angle of the motor under test.

[0041] On the one hand, converting the first, second, and third sine signals into the fourth and fifth sine signals includes:

[0042] If the first sine signal is an unbiased sine signal, the first sine signal is taken as the fifth sine signal;

[0043] Subtract the second sine signal from the third sine signal to obtain the fourth sine signal.

[0044] This application embodiment also provides a motor rotor position detection device, including an acquisition unit, a conversion unit, an adjustment unit, and a determination unit;

[0045] The acquisition unit is used to acquire the voltage values ​​of each Hall sensor; wherein, each Hall sensor is symmetrically distributed on the drive board of the motor under test, and in the circumferential direction, each Hall sensor is deployed in the middle of adjacent stator slots with opposite winding currents, and in the radial direction, each Hall sensor is separated from the motor rotor magnet by a set distance.

[0046] The conversion unit is used to convert the voltage values ​​of each Hall sensor into Gaussian values ​​of magnetic field strength;

[0047] The adjustment unit is used to adjust the peak value of each magnetic field strength Gaussian value according to the peak value normalization method.

[0048] The determination unit is used to determine the rotor electrical angle of the motor under test based on the peak value of the adjusted magnetic field strength Gaussian value and the phase difference value of each Hall sensor.

[0049] This application embodiment also provides a motor rotor position detection system, including multiple Hall sensors and a processor; wherein, the multiple Hall sensors are symmetrically distributed on the drive board of the motor under test, and each Hall sensor is deployed in the middle of the stator slots with opposite stator winding currents in the circumferential direction, and each Hall sensor is separated from the motor rotor magnet by a set distance in the radial direction.

[0050] The processor communicates with each Hall sensor to acquire the voltage value of each Hall sensor; converts the voltage value of each Hall sensor into a Gaussian value of magnetic field strength; adjusts the peak value of each Gaussian value of magnetic field strength according to the peak normalization method; and determines the rotor electrical angle of the motor under test based on the peak value of the adjusted Gaussian value of magnetic field strength and the phase difference value of each Hall sensor.

[0051] This application also provides a joint module applicable to the above-described motor rotor position detection method.

[0052] As can be seen from the above technical solution, the voltage values ​​of each Hall sensor are obtained. The Hall sensors are symmetrically distributed on the drive board of the motor under test. Circumferentially, each Hall sensor is positioned between adjacent stator slots with opposite winding currents, and radially, each Hall sensor is separated from the motor rotor magnet by a set distance. The voltage values ​​of each Hall sensor are converted into Gaussian values ​​of magnetic field strength. Considering the axial movement of the motor rotor, which can cause inconsistencies in the peak values ​​of the Gaussian magnetic field strength of the Hall sensors, the peak values ​​of each Gaussian magnetic field strength can be adjusted using peak normalization. Based on the adjusted peak values ​​of the Gaussian magnetic field strength and the phase difference between each Hall sensor, the rotor electrical angle of the motor under test can be determined. In this technical solution, by symmetrically distributing multiple Hall sensors on the drive board, axial space length is saved, ensuring the parallelism between the drive board and the motor rotor magnet. Furthermore, the circumferential positioning of each Hall sensor between adjacent stator slots with opposite winding currents can counteract the influence of the armature magnetic field generated by the current on the Hall sensor. The radial separation of each Hall sensor from the motor rotor magnet ensures that the magnetic field strength is within a reasonable range detectable by the Hall sensor. Peak value normalization can further reduce the impact of axial movement of the motor rotor. This solution offers strong anti-interference capabilities, ensures the accuracy of the motor rotor's electrical angle, and relies solely on multiple Hall effect sensors to determine the rotor's electrical angle, thus saving hardware costs. Attached Figure Description

[0053] To more clearly illustrate the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 A flowchart of a motor rotor position detection method provided in an embodiment of this application;

[0055] Figure 2 A schematic diagram showing a Hall sensor uniformly and symmetrically arranged on a driver board, as provided in an embodiment of this application;

[0056] Figure 3 A schematic diagram of a Hall sensor deployed in a stator slot according to an embodiment of this application;

[0057] Figure 4 This is a schematic diagram of the structure of a motor rotor position detection device provided in an embodiment of this application. Detailed Implementation

[0058] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this application.

[0059] The terms "comprising" and "having," and any variations thereof, in the specification and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may include steps or units not listed.

[0060] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0061] Next, a method for detecting the position of a motor rotor provided in the embodiments of this application will be described in detail. Figure 1 A flowchart of a motor rotor position detection method provided in this application embodiment, the method including:

[0062] S101: Obtain the voltage values ​​of each Hall sensor.

[0063] In this embodiment of the application, the electrical angle of the motor rotor is detected based on a Hall sensor, thereby determining the rotor position.

[0064] The number of Hall sensors can be set to six. To save axial space and reduce rotor shaft movement caused by installation, the six Hall sensors can be symmetrically arranged on the drive board of the motor under test. To avoid interference between adjacent Hall sensors, the six Hall sensors can be evenly distributed on the drive board. The following descriptions will use a uniformly symmetrical distribution of Hall sensors as an example.

[0065] To counteract the effect of the armature magnetic field generated by the current on the Hall sensor, each Hall sensor needs to be deployed in the middle of an adjacent stator slot with opposite winding currents in the circumferential position. Figure 2 This is a schematic diagram showing a Hall sensor uniformly and symmetrically arranged on a driver board, according to an embodiment of this application. Figure 2 Taking six Hall sensors as an example, each Hall sensor is deployed in the middle of the stator slots of two adjacent stators.

[0066] In practical applications, the voltage values ​​of each Hall sensor can be obtained through ADC sampling.

[0067] The motor contains a large number of stator slots, and the specific location of the Hall sensor in which it is placed is affected by the number of slots, the number of pole pairs, and the winding method.

[0068] In practice, the number of slots, number of pole pairs, and winding method of the motor under test can be obtained; based on the number of slots, number of pole pairs, winding method of the motor under test and the total number of Hall sensors, the circumferential deployment position of each Hall sensor can be determined.

[0069] Figure 3 This is a schematic diagram illustrating the deployment of a Hall sensor in a stator slot according to an embodiment of this application. Figure 3 The example below uses 24 slots, 28 poles, and 6 Hall sensors. With 28 poles, the number of pole pairs is 28 / 2 = 14. Figure 3 Numbers ① to ⑥ represent the circumferential deployment positions of the six Hall sensors. Figure 3 As can be seen, the winding currents of the two adjacent stators of each Hall sensor are in opposite directions. The angle between the positioning pin and the Hall sensor numbered ① is (360° / 24) / 2 = 7.5°.

[0070] To ensure the magnetic field strength remains within the reasonable range of the Hall sensors, each Hall sensor is radially separated from the motor rotor magnet by a predetermined distance. The predetermined distance is determined based on the magnetic field strength between each Hall sensor and the motor rotor magnet. In practical applications, magnetic field simulation can be used to determine the distance between the Hall sensors and the motor rotor magnet, ensuring the magnetic field strength remains within the reasonable range of the Hall sensors. Taking any single Hall sensor (the target Hall sensor) as an example, magnetic field simulation can be used to determine the magnetic field strength between the target Hall sensor and the motor rotor magnet at different distances; the distance corresponding to the magnetic field strength falling within the predetermined range is then taken as the predetermined distance.

[0071] S102: Converts the voltage values ​​of each Hall sensor into Gaussian values ​​of magnetic field strength.

[0072] To calculate the rotor electrical angle, the voltage values ​​of each Hall sensor need to be converted into Gaussian values ​​of magnetic field strength. The conversion method is a relatively mature technology and will not be elaborated here.

[0073] S103: Adjust the peak value of each magnetic field strength Gaussian value according to the peak value normalization method.

[0074] By uniformly and symmetrically arranging multiple Hall sensors on the drive board, the parallelism between the drive board and the motor rotor magnet is ensured. However, axial movement of the motor rotor causes changes in the distance between them, resulting in inconsistent peak values ​​of the Gaussian magnetic field strength obtained by each Hall sensor. Therefore, even with symmetrical placement of the Hall sensors, two Hall sensors symmetrically arranged at 180 degrees will show different peak values: one side will have a larger peak value, while the other side will have a smaller peak value. To address the inconsistency in Hall sensor peak values ​​caused by distance variations, the peak values ​​of the Hall sensors can be normalized.

[0075] In practical applications, multiple peak values ​​of the magnetic field strength Gaussian value of each Hall sensor can be obtained when the motor under test rotates for multiple revolutions; the peak values ​​corresponding to the Hall sensors with symmetrical relationships are normalized to determine the normalized peak value corresponding to the Hall sensors with symmetrical relationships.

[0076] Combination Figure 3 The schematic diagram shows that Hall sensors ① and ④ are symmetrical, as are Hall sensors ② and ⑤, and Hall sensors ③ and ⑥. Through peak value normalization, Hall sensors ① and ④ have the same peak value, Hall sensors ② and ⑤ have the same peak value, and Hall sensors ③ and ⑥ have the same peak value. Ideally, through peak value normalization, the peak values ​​of Hall sensors ① through ⑥ should all be the same.

[0077] S104: Based on the peak value of the adjusted magnetic field strength Gaussian value and the phase difference value of each Hall sensor, the rotor electrical angle of the motor under test is determined.

[0078] In this embodiment of the application, the included angle between adjacent Hall sensors can be determined based on the number of slots of the motor under test and the total number of Hall sensors; the phase difference between adjacent Hall sensors can be determined based on the number of pole pairs and the included angle between adjacent Hall sensors.

[0079] To determine the angle between adjacent Hall sensors, in a specific implementation, the circumferential angle can be divided by the number of slots in the motor under test to obtain the angle between adjacent locating pins; the number of slots in the motor under test can be divided by the total number of Hall sensors to obtain the upper limit of the electrical angle. An even number less than or equal to the upper limit of the electrical angle is taken as the number of electrical angles between adjacent Hall sensors; the product of the angle between adjacent locating pins and the number of electrical angles between adjacent Hall sensors is taken as the angle between adjacent Hall sensors.

[0080] For example, if there are 6 Hall sensors in total and 24 slots in the motor under test, the angle between adjacent locating pins can be calculated to be 360° / 24 = 15°. The upper limit of the electrical angle is 24 / 6 = 4. Therefore, the number of electrical angles between adjacent Hall sensors can be either 2 or 4. Taking 4 electrical angles between adjacent Hall sensors as an example, the angle between them is 15° * 4 = 60°. Taking 2 electrical angles between adjacent Hall sensors as an example, the angle is 15° * 2 = 30°.

[0081] It should be noted that, since the Hall sensors are symmetrically distributed, it is only necessary to determine the angle between the first three Hall sensors, and the remaining three Hall sensors can be deployed directly according to the symmetrical distribution.

[0082] In addition to the methods described above, if all Hall sensors are evenly distributed, the circumference angle can be directly divided by the total number of Hall sensors to obtain the included angle between adjacent Hall sensors.

[0083] For example, if there are a total of 6 Hall sensors, and the 6 Hall sensors are evenly distributed, the included angle between adjacent Hall sensors is 360° / 6 = 60°.

[0084] In practical implementation, the phase difference calculation formula can be called to analyze the number of pole pairs and the angle between adjacent Hall sensors to determine the phase difference between adjacent Hall sensors; the phase difference calculation formula is as follows:

[0085] ;

[0086] in, The value represents the phase difference between adjacent Hall sensors, α represents the angle between adjacent Hall sensors, A represents the number of electrical angles between adjacent Hall sensors, and P represents the number of pole pairs.

[0087] by Figure 3 Taking the schematic diagram shown as an example, the number of pole pairs is 14, and the total number of Hall sensors is 6. The 6 Hall sensors are evenly and symmetrically distributed, so the included angle between adjacent Hall sensors is 360 / 6 = 60 degrees.

[0088] The number of electrical angles between adjacent Hall sensors can be determined based on the total number of complete locating pin pairs between adjacent Hall sensors. Figure 3 It can be seen that there are two pairs of complete positioning pins between adjacent Hall sensors, so the number of electrical angles is 2. Combining this with the phase difference calculation formula, the phase difference between adjacent Hall sensors can be determined: .

[0089] Based on this phase difference, the waveform of the Gaussian value of the magnetic field strength of each Hall sensor can be determined.

[0090] The waveform of the Hall sensor in serial number ① is: A1sin(θ);

[0091] The waveform of the Hall sensor in serial number ② is: A2sin(θ+120°);

[0092] The waveform of the Hall sensor in serial number ③ is: A3sin(θ+240°) = -A3sin(θ+60°);

[0093] The waveform of the Hall sensor in sequence ④ is: B1sin(θ+360°) = B1sin(θ);

[0094] The waveform of the Hall sensor in serial number ⑤ is: B2sin(θ+480°) = B2sin(θ+120°);

[0095] The waveform of the Hall sensor in serial number ⑥ is: B3sin(θ+600°) = -B3sin(θ+60°);

[0096] Among them, A1, A2, A3, B1, B2 and B3 are amplitude coefficients.

[0097] With a total of six Hall sensors, the sinusoidal signal of each Hall sensor is determined based on the peak value of the adjusted magnetic field strength Gaussian value and the phase difference of each Hall sensor. According to the principle of symmetry, the sinusoidal signals of the six Hall sensors are converted into three sinusoidal signals with a phase difference of sixty degrees: a first sinusoidal signal, a second sinusoidal signal, and a third sinusoidal signal.

[0098] Combining the waveforms of the six Hall sensors mentioned above, and through peak value normalization processing, the amplitude coefficients of each Hall sensor waveform are the same. At this time, the sinusoidal signals of the six Hall sensors will become three sinusoidal signals, namely the first sinusoidal signal A′sin(θ), the second sinusoidal signal A′sin(θ+120°), and the third sinusoidal signal -A′sin(θ+60°). A′ represents the adjusted amplitude coefficient.

[0099] The first, second, and third sine signals are converted into the fourth and fifth sine signals.

[0100] Combining the expressions for the first, second, and third sine signals above, it can be seen that the first sine signal is an unbiased sine signal, so the first sine signal can be used as the fifth sine signal; the second sine signal is subtracted from the third sine signal to obtain the fourth sine signal.

[0101] The fourth and fifth sine signals are processed by arctangent to determine the rotor electrical angle of the motor under test.

[0102] In practical applications, the second and third sine signals can be subtracted to obtain the fourth sine signal, i.e. Taking the first sine signal as the fifth sine signal, and then dividing the fourth and fifth sine signals, we get: .

[0103] Assuming, Where y can be obtained by the processor sampling calculation, then the following can be calculated: The value of θ is the rotor electrical angle of the motor under test.

[0104] In practical applications, the number of slots, pole pairs, and winding method of the motor under test must meet the requirements of the Hall sensor deployment to enable rotor position detection. Therefore, before determining the circumferential deployment position of each Hall sensor based on its slot number, pole pairs, winding method, and the total number of Hall sensors, it's necessary to determine if the winding method of the motor under test satisfies the condition that adjacent stator winding currents are opposite. If the winding method satisfies the condition that adjacent stator winding currents are opposite, it's then necessary to determine if the number of slots of the motor under test is an integer multiple of the total number of Hall sensors.

[0105] Taking a total of 6 Hall sensors as an example, the number of slots of the motor under test needs to be a multiple of 6, such as 12, 18, 24, etc.

[0106] If the number of slots of the motor under test is an integer multiple of the total number of Hall sensors, it can be further determined whether the number of pole pairs of the motor under test meets the phase requirements.

[0107] Phase requirements may include a phase calculated based on the number of pole pairs that satisfies the following formula:

[0108] ;

[0109] Assuming the number of pole pairs is 14 and A=2, substituting into the left side of the above formula, the phase is calculated to be 120°, indicating that it meets the requirements.

[0110] If the number of pole pairs of the motor under test meets the phase requirements, the operation of determining the circumferential deployment position of each Hall sensor is performed based on the number of slots, number of pole pairs, winding method, and total number of Hall sensors of the motor under test.

[0111] As can be seen from the above technical solution, the voltage values ​​of each Hall sensor are obtained. The Hall sensors are symmetrically distributed on the drive board of the motor under test. Circumferentially, each Hall sensor is positioned between adjacent stator slots with opposite winding currents, and radially, each Hall sensor is separated from the motor rotor magnet by a set distance. The voltage values ​​of each Hall sensor are converted into Gaussian values ​​of magnetic field strength. Considering the axial movement of the motor rotor, which can cause inconsistencies in the peak values ​​of the Gaussian magnetic field strength of the Hall sensors, the peak values ​​of each Gaussian magnetic field strength can be adjusted using peak normalization. Based on the adjusted peak values ​​of the Gaussian magnetic field strength and the phase difference between each Hall sensor, the rotor electrical angle of the motor under test can be determined. In this technical solution, by symmetrically distributing multiple Hall sensors on the drive board, axial space length is saved, ensuring the parallelism between the drive board and the motor rotor magnet. Furthermore, the circumferential positioning of each Hall sensor between adjacent stator slots with opposite winding currents can counteract the influence of the armature magnetic field generated by the current on the Hall sensor. The radial separation of each Hall sensor from the motor rotor magnet ensures that the magnetic field strength is within a reasonable range detectable by the Hall sensor. Peak value normalization can further reduce the impact of axial movement of the motor rotor. This solution offers strong anti-interference capabilities, ensures the accuracy of the motor rotor's electrical angle, and relies solely on multiple Hall effect sensors to determine the rotor's electrical angle, thus saving hardware costs.

[0112] Figure 4 A schematic diagram of the structure of a motor rotor position detection device provided in an embodiment of this application includes an acquisition unit 41, a conversion unit 42, an adjustment unit 43, and a determination unit 44;

[0113] The acquisition unit 41 is used to acquire the voltage values ​​of each Hall sensor; wherein, each Hall sensor is symmetrically distributed on the drive board of the motor under test, and each Hall sensor is deployed in the middle of adjacent stator slots with opposite winding currents in the circumferential direction, and each Hall sensor is separated from the motor rotor magnet by a set distance in the radial direction.

[0114] The conversion unit 42 is used to convert the voltage values ​​of each Hall sensor into Gaussian values ​​of magnetic field strength;

[0115] Adjustment unit 43 is used to adjust the peak value of each magnetic field strength Gaussian value according to the peak value normalization method;

[0116] The determining unit 44 is used to determine the rotor electrical angle of the motor under test based on the peak value of the adjusted magnetic field strength Gaussian value and the phase difference value of each Hall sensor.

[0117] In some embodiments, the apparatus includes a parameter acquisition unit and a position determination unit for determining the circumferential deployment position of each Hall sensor;

[0118] The parameter acquisition unit is used to acquire the number of slots, number of pole pairs, and winding method of the motor under test.

[0119] The position determination unit is used to determine the circumferential deployment position of each Hall sensor based on the number of slots, number of pole pairs, winding method of the motor under test, and the total number of Hall sensors.

[0120] In some embodiments, before determining the circumferential deployment position of each Hall sensor based on the number of slots, number of pole pairs, winding method of the motor under test and the total number of Hall sensors, a first judgment unit, a second judgment unit and a third judgment unit are further included.

[0121] The first judgment unit is used to determine whether the winding method of the motor under test satisfies the condition that the adjacent stator winding currents are opposite.

[0122] The second judgment unit is used to determine whether the number of slots of the motor under test is an integer multiple of the total number of Hall sensors when the winding method of the motor under test satisfies that the adjacent stator winding currents are opposite.

[0123] The third judgment unit is used to determine whether the number of pole pairs of the motor under test meets the phase requirement when the number of slots of the motor under test is an integer multiple of the total number of Hall sensors; when the number of pole pairs of the motor under test meets the phase requirement, the trigger position determination unit performs the operation of determining the circumferential deployment position of each Hall sensor according to the number of slots, number of pole pairs, winding method and total number of Hall sensors of the motor under test.

[0124] In some embodiments, the determination of the set distance between each Hall sensor and the motor rotor magnet further includes a distance determination unit;

[0125] The distance determination unit is used to determine the magnetic field strength of the target Hall sensor and the motor rotor magnet at different distances using magnetic field simulation; wherein, the target Hall sensor is any one of the Hall sensors; the distance corresponding to the magnetic field strength falling within the set strength range is taken as the set distance.

[0126] In some embodiments, after obtaining the number of slots, number of pole pairs, and winding method of the motor under test, the system further includes an angle determination unit and a phase difference determination unit.

[0127] Angle determination unit is used to determine the angle between adjacent Hall sensors based on the number of slots of the motor under test and the total number of Hall sensors;

[0128] The phase difference determination unit is used to determine the phase difference between adjacent Hall sensors based on the number of pole pairs and the angle between adjacent Hall sensors.

[0129] In some embodiments, the included angle determination unit is used to perform a division operation between the circumferential angle and the number of slots of the motor under test to obtain the included angle between adjacent positioning pins; perform a division operation between the number of slots of the motor under test and the total number of Hall sensors to obtain the upper limit value of the electrical angle; take an even number less than or equal to the upper limit value of the electrical angle as the number of electrical angles between adjacent Hall sensors; and take the product of the included angle between adjacent positioning pins and the number of electrical angles between adjacent Hall sensors as the included angle between adjacent Hall sensors.

[0130] In some embodiments, the phase difference determination unit is used to call the phase difference calculation formula to analyze the number of pole pairs and the angle between adjacent Hall sensors to determine the phase difference between adjacent Hall sensors; the phase difference calculation formula is as follows:

[0131] ;

[0132] in, The value represents the phase difference between adjacent Hall sensors, α represents the angle between adjacent Hall sensors, A represents the number of electrical angles between adjacent Hall sensors, and P represents the number of pole pairs.

[0133] In some embodiments, the adjustment unit is used to obtain multiple peak values ​​of the magnetic field strength Gaussian value of each Hall sensor when the motor under test rotates multiple times.

[0134] The peak values ​​corresponding to the Hall sensors with symmetrical relationships are normalized to determine the normalized peak value corresponding to the Hall sensors with symmetrical relationships.

[0135] In some embodiments, the determining unit is used to determine the sinusoidal signal of each Hall sensor based on the peak value of the adjusted magnetic field strength Gaussian value and the phase difference value of each Hall sensor when the total number of Hall sensors is six.

[0136] Based on the principle of symmetry, the sinusoidal signals from the six Hall sensors are converted into three sinusoidal signals—a first sinusoidal signal, a second sinusoidal signal, and a third sinusoidal signal—that are 60 degrees out of phase.

[0137] Convert the first, second, and third sine signals into the fourth and fifth sine signals;

[0138] The fourth and fifth sine signals are processed by arctangent to determine the rotor electrical angle of the motor under test.

[0139] In some embodiments, the determining unit is configured to, when the first sine signal is an unbiased sine signal, use the first sine signal as the fifth sine signal; and subtract the second sine signal from the third sine signal to obtain the fourth sine signal.

[0140] Figure 4 The description of the features in the corresponding embodiments can be found in [reference needed]. Figure 1 The relevant descriptions of the corresponding embodiments will not be repeated here.

[0141] As can be seen from the above technical solution, the voltage values ​​of each Hall sensor are obtained. The Hall sensors are symmetrically distributed on the drive board of the motor under test. Circumferentially, each Hall sensor is positioned between adjacent stator slots with opposite winding currents, and radially, each Hall sensor is separated from the motor rotor magnet by a set distance. The voltage values ​​of each Hall sensor are converted into Gaussian values ​​of magnetic field strength. Considering the axial movement of the motor rotor, which can cause inconsistencies in the peak values ​​of the Gaussian magnetic field strength of the Hall sensors, the peak values ​​of each Gaussian magnetic field strength can be adjusted using peak normalization. Based on the adjusted peak values ​​of the Gaussian magnetic field strength and the phase difference between each Hall sensor, the rotor electrical angle of the motor under test can be determined. In this technical solution, by symmetrically distributing multiple Hall sensors on the drive board, axial space length is saved, ensuring the parallelism between the drive board and the motor rotor magnet. Furthermore, the circumferential positioning of each Hall sensor between adjacent stator slots with opposite winding currents can counteract the influence of the armature magnetic field generated by the current on the Hall sensor. The radial separation of each Hall sensor from the motor rotor magnet ensures that the magnetic field strength is within a reasonable range detectable by the Hall sensor. Peak value normalization can further reduce the impact of axial movement of the motor rotor. This solution offers strong anti-interference capabilities, ensures the accuracy of the motor rotor's electrical angle, and relies solely on multiple Hall effect sensors to determine the rotor's electrical angle, thus saving hardware costs.

[0142] This application embodiment also provides a motor rotor position detection system, including multiple Hall sensors and a processor; wherein, the multiple Hall sensors are uniformly and symmetrically distributed on the drive board of the motor under test, and each Hall sensor is deployed in the middle of the stator slots with opposite stator winding currents in adjacent stators;

[0143] The processor communicates with each Hall sensor to acquire the voltage value of each Hall sensor; converts the voltage value of each Hall sensor into a Gaussian value of magnetic field strength; adjusts the peak value of each Gaussian value of magnetic field strength according to the peak normalization method; and determines the rotor electrical angle of the motor under test based on the peak value of the adjusted Gaussian value of magnetic field strength and the phase difference value of each Hall sensor.

[0144] For a description of the features in the embodiment of the motor rotor position detection system, please refer to the relevant description of the embodiment of the motor rotor position detection method, which will not be repeated here.

[0145] As can be seen from the above technical solution, multiple Hall sensors are symmetrically distributed on the drive board of the motor under test. Circumferentially, each Hall sensor is positioned between adjacent stator slots with opposite stator winding currents, and radially, each Hall sensor is separated from the motor rotor magnet by a set distance. The processor communicates with each Hall sensor to acquire its voltage value. The voltage values ​​of each Hall sensor are converted into Gaussian values ​​of magnetic field strength. Considering the axial movement of the motor rotor, which can cause inconsistencies in the peak values ​​of the Gaussian magnetic field strength of the Hall sensors, the peak values ​​can be adjusted using peak normalization. Based on the adjusted peak values ​​of the Gaussian magnetic field strength and the phase difference between the Hall sensors, the rotor electrical angle of the motor under test can be determined. In this technical solution, by symmetrically distributing multiple Hall sensors on the drive board, axial space length is saved, ensuring the parallelism between the drive board and the motor rotor magnet. Furthermore, the circumferential positioning of each Hall sensor between adjacent stator slots with opposite winding currents can counteract the influence of the armature magnetic field generated by the current on the Hall sensors. In the radial direction, each Hall sensor is spaced a predetermined distance from the motor rotor magnet to ensure that the magnetic field strength is within a reasonable range detectable by the Hall sensors. Peak value normalization further reduces the impact of axial movement of the motor rotor. This solution offers strong anti-interference capabilities, ensures the accuracy of the motor rotor's electrical angle, and relies on only multiple Hall sensors to determine the rotor's electrical angle, thus saving hardware costs.

[0146] An embodiment of this application also provides a joint module applicable to the above-described motor rotor position detection method.

[0147] Embodiments of this application also provide an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor is configured to run the computer program to perform the steps in any of the above embodiments of the motor rotor position detection method.

[0148] Embodiments of this application also provide a computer-readable storage medium storing a computer program, wherein the computer program is configured to execute the steps in any of the above embodiments of the motor rotor position detection method when running.

[0149] In one exemplary embodiment, the aforementioned computer-readable storage medium may include, but is not limited to, various media capable of storing computer programs, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard drive, magnetic disk, or optical disk.

[0150] The embodiments of this application also provide a computer program product, which includes a computer program that, when executed by a processor, implements the steps in any of the embodiments of the motor rotor position detection method described above.

[0151] Embodiments of this application also provide another computer program product, including a non-volatile computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps in any of the above embodiments of the motor rotor position detection method.

[0152] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0153] The foregoing has provided a detailed description of a method, apparatus, system, and joint module for detecting the position of a motor rotor. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and its core ideas. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from its principles, and these improvements and modifications also fall within the protection scope of this application.

Claims

1. A method for detecting the position of a motor rotor, characterized in that, include: The voltage values ​​of each Hall sensor are obtained; wherein, each Hall sensor is symmetrically distributed on the drive board of the motor under test, and each Hall sensor is deployed in the middle of adjacent stator slots with opposite winding currents in the circumferential direction, and each Hall sensor is separated from the motor rotor magnet by a set distance in the radial direction; The voltage values ​​of each Hall sensor are converted into Gaussian values ​​of magnetic field strength; Adjust the peak value of each Gaussian value of the magnetic field strength according to the peak normalization method; The rotor electrical angle of the motor under test is determined based on the peak value of the adjusted magnetic field strength Gaussian value and the phase difference value of each Hall sensor.

2. The method for detecting the position of a motor rotor according to claim 1, characterized in that, The method for determining the circumferential deployment positions of each of the Hall sensors includes: Obtain the number of slots, number of pole pairs, and winding method of the motor under test; The circumferential deployment position of each Hall sensor is determined based on the number of slots, number of pole pairs, winding method of the motor under test, and the total number of Hall sensors.

3. The method for detecting the position of a motor rotor according to claim 2, characterized in that, Before determining the circumferential deployment position of each Hall sensor based on the number of slots, number of pole pairs, winding method of the motor under test, and the total number of Hall sensors, the process further includes: Determine whether the winding method of the motor under test satisfies the condition that the adjacent stator winding currents are opposite; If the winding method of the motor under test satisfies that the adjacent stator winding currents are opposite, determine whether the number of slots of the motor under test is an integer multiple of the total number of Hall sensors; If the number of slots of the motor under test is an integer multiple of the total number of Hall sensors, determine whether the number of pole pairs of the motor under test meets the phase requirements. If the number of pole pairs of the motor under test meets the phase requirements, the operation of determining the circumferential deployment position of each Hall sensor is performed based on the number of slots, number of pole pairs, winding method of the motor under test, and the total number of Hall sensors.

4. The method for detecting the position of a motor rotor according to claim 2, characterized in that, The method for determining the set distance between each Hall sensor and the motor rotor magnet includes: The magnetic field strength of the target Hall sensor and the motor rotor magnet at different distances was determined using magnetic field simulation; where the target Hall sensor is any one of the Hall sensors. The distance corresponding to a magnetic field strength within a set strength range is taken as the set distance.

5. The method for detecting the position of a motor rotor according to claim 2, characterized in that, After obtaining the number of slots, number of pole pairs, and winding method of the motor under test, the process also includes: The included angle between adjacent Hall sensors is determined based on the number of slots in the motor under test and the total number of Hall sensors. The phase difference between adjacent Hall sensors is determined based on the number of pole pairs and the angle between adjacent Hall sensors.

6. The method for detecting the position of a motor rotor according to claim 5, characterized in that, Based on the number of slots in the motor under test and the total number of Hall sensors, the included angle between adjacent Hall sensors is determined, including: Perform a division operation between the circumferential angle and the number of slots of the motor under test to obtain the included angle between adjacent positioning pins; perform a division operation between the number of slots of the motor under test and the total number of Hall sensors to obtain the upper limit value of the electrical angle; An even number less than or equal to the upper limit of the electrical angle is taken as the number of electrical angles between adjacent Hall sensors; The product of the angle between the adjacent positioning pins and the number of electrical angles between the adjacent Hall sensors is taken as the angle between the adjacent Hall sensors.

7. The method for detecting the position of a motor rotor according to claim 5, characterized in that, Based on the number of pole pairs and the angle between adjacent Hall sensors, the phase difference between adjacent Hall sensors is determined, including: The phase difference calculation formula is used to analyze the angle between the number of pole pairs and adjacent Hall sensors to determine the phase difference between adjacent Hall sensors; the phase difference calculation formula is as follows: ； in, The value represents the phase difference between adjacent Hall sensors, α represents the angle between adjacent Hall sensors, A represents the number of electrical angles between adjacent Hall sensors, and P represents the number of pole pairs.

8. The method for detecting the position of a motor rotor according to claim 1, characterized in that, The peak values ​​of the Gaussian values ​​of the magnetic field strengths are adjusted according to the peak normalization method, including: The Gaussian values ​​of the magnetic field strength of each Hall sensor are obtained as multiple peak values ​​of the motor under test rotate multiple times. The peak values ​​corresponding to the Hall sensors with symmetrical relationships are normalized to determine the normalized peak value corresponding to the Hall sensors with symmetrical relationships.

9. The method for detecting the position of a motor rotor according to claim 1, characterized in that, Based on the peak value of the adjusted Gaussian magnetic field strength and the phase difference values ​​of each Hall sensor, the rotor electrical angle of the motor under test is determined, including: When the total number of Hall sensors is six, the sinusoidal signal of each Hall sensor is determined based on the peak value of the adjusted magnetic field strength Gaussian value and the phase difference value of each Hall sensor. Based on the principle of symmetry, the sinusoidal signals from the six Hall sensors are converted into three sinusoidal signals—a first sinusoidal signal, a second sinusoidal signal, and a third sinusoidal signal—that are 60 degrees out of phase. The first sine signal, the second sine signal, and the third sine signal are converted into a fourth sine signal and a fifth sine signal; The fourth and fifth sine signals are subjected to arctangent processing to determine the rotor electrical angle of the motor under test.

10. The method for detecting the position of a motor rotor according to claim 9, characterized in that, Converting the first sine wave signal, the second sine wave signal, and the third sine wave signal into a fourth sine wave signal and a fifth sine wave signal includes: If the first sine signal is an unbiased sine signal, the first sine signal is used as the fifth sine signal; Subtract the second sine signal from the third sine signal to obtain the fourth sine signal.

11. A position detection device for a motor rotor, characterized in that, It includes an acquisition unit, a conversion unit, an adjustment unit, and a determination unit; The acquisition unit is used to acquire the voltage values ​​of each Hall sensor; wherein, each Hall sensor is symmetrically distributed on the drive board of the motor under test, and in the circumferential direction, each Hall sensor is deployed in the middle of adjacent stator slots with opposite winding currents, and in the radial direction, each Hall sensor is separated from the motor rotor magnet by a set distance. The conversion unit is used to convert the voltage value of each Hall sensor into a Gaussian value of magnetic field strength; The adjustment unit is used to adjust the peak value of each Gaussian value of the magnetic field strength according to the peak value normalization method. The determining unit is used to determine the rotor electrical angle of the motor under test based on the peak value of the adjusted magnetic field strength Gaussian value and the phase difference value of each Hall sensor.

12. A position detection system for a motor rotor, characterized in that, It includes multiple Hall sensors and a processor; wherein, the multiple Hall sensors are symmetrically distributed on the drive board of the motor under test, and each Hall sensor is deployed in the middle of the stator slots with opposite stator winding currents in the circumferential direction, and each Hall sensor is separated from the motor rotor magnet by a set distance in the radial direction; The processor is communicatively connected to each of the Hall sensors to acquire the voltage values ​​of each Hall sensor; convert the voltage values ​​of each Hall sensor into Gaussian values ​​of magnetic field strength; adjust the peak value of each Gaussian value of magnetic field strength according to the peak value normalization method; and determine the rotor electrical angle of the motor under test based on the adjusted peak value of the Gaussian value of magnetic field strength and the phase difference value of each Hall sensor.

13. A joint module, characterized in that, The method for detecting the position of a motor rotor is applicable to any one of the claims 1 to 10 above.

Images