Method for judging and correcting Hall and winding phase sequence of brushless direct-current motor

Abstract

The invention relates to a brushless DC motor Hall and winding phase sequence determination and correction method, which comprises the following steps: establishing a circuit for interpretation and correction, including three resistors, two DC stabilized power supplies, an oscilloscope with more than three channels, a connecting cable and a manufactured three-phase brushless DC motor; power supplies of three Hall elements of the brushless direct current motor are connected to a positive electrode of the first direct current stabilized power supply, and ground ends of the three Hall elements are connected to a negative electrode of the first direct current stabilized power supply; the outputs Vout of the three-phase Hall elements HA, HB and HC are respectively connected with the positive electrode of the first direct-current stabilized power supply through a resistor, and the outputs HA, HB and HC of the three-phase Hall elements and the ground end are respectively connected to the positive electrode terminal and the negative electrode terminal of the oscilloscope probe; two of the outgoing lines A, B and C of the three-phase winding are connected to a second direct-current stabilized power supply; and judging and correcting the phase sequence and color of the three-phase winding and judging and correcting the phase sequence and color of the three-phase Hall through the built circuit. The method meets the requirements of a set Hall truth table.

Description

Technical Field

[0001] The invention belongs to the technical field of micro motor design and detection, and in particular relates to a method for determining and correcting the Hall and winding phase sequence of a brushless DC motor that is independent of a drive circuit. Background Art

[0002] Three-phase permanent magnet brushless DC motors have been widely used in servo control systems due to their simple control, easy implementation, high cost performance and high reliability. Permanent magnet brushless DC motors use position sensors to identify the position of the rotor poles and use electronic commutation to replace the mechanical friction commutation between the brushes and the commutator of the brushed DC motor. The components that perform the electronic commutation function are the rotor position sensor and the drive control circuit. The commonly used rotor position sensor is a switch-type Hall device, which identifies the N and S poles of the rotor permanent magnet and converts them into digital voltages 1 and 0. The three-phase permanent magnet brushless DC motor uses three Hall devices, so there are 2 3 = 8 states, of which (0, 0, 0) and (1, 1, 1) are unused states. According to the electromagnetic principle of the brushless DC motor, the installation position of the Hall device is shown in Table 1.

[0003] Table 1 Correspondence between the position of the Hall device and the magnetomotive force of the three-phase winding

[0004]

[0005] The installation position of the Hall device coincides with the positive direction of the axis of the three-phase winding magnetomotive force. Its mirror image positions HA′, HB′, and HC′ are the reverse positions of the three-phase magnetomotive force axis, and are also the correct positions of the Hall device, which logically present a "not" relationship. In general, the Hall device is placed at the positive coincidence position of the three-phase winding magnetomotive force. If installed in the mirror image position, it is necessary to perform a "not" operation on the drive circuit, or face the non-marked surface of the Hall circuit to the magnetic pole.

[0006] At present, most brushless DC motors operate in a three-phase full-wave six-state mode. In one working cycle, there are six winding switching states: AB, AC, BC, BA, CA, and CB. The task of the three Hall sensors is to obtain six commutation points. The output duty ratio of each Hall circuit is 1:1, and the three Hall circuits are distributed at an electrical angle of 120° in the circumferential space. For a three-phase permanent magnet brushless DC motor to work normally, its stator armature magnetomotive force axis is divided into six states within an electrical angle of 360°, and switches and jumps forward in sequence. The switching point is the commutation point identified by the Hall sensor. Therefore, the Hall sensor output and winding conduction phase sequence of the three-phase full-wave permanent magnet brushless motor need to be executed according to the requirements of a certain state truth table, so as to meet the continuous and orderly switching of the motor winding, drag the motor rotor magnetic poles to continuously track the motor stator winding magnetomotive force, and achieve the purpose of continuous rotation. An example of general significance is shown in Table 2.

[0007] Table 2 The power-on sequence of each phase winding and the truth table of the Hall position signal (viewed from the shaft extension end, the motor shaft rotates counterclockwise)

[0008]

[0009] Arrange the three-phase windings A, B, C and the Hall devices HA, HB, HC according to Table 1 and Table 2, and define the corresponding colors. Let's assume that the lead wire colors of the three-phase windings A, B, C are defined as S1, S2, S3, and the colors of the lead wires of the three Hall device outputs HA, HB, HC are defined as S4, S5, S6. The brushless DC motor made and connected to the drive circuit may not rotate correctly. This is because there are many factors that affect the phase sequence, such as the positive and negative directions of the winding, the forward and reverse directions, the color matching, the placement of the Hall sensitive surface, etc. The winding phase sequence or the Hall phase sequence needs to be replaced with the help of the drive circuit, and repeated tests are performed until the motor can rotate normally. At this moment, even if the motor rotates correctly, it does not mean that the Hall state triggering and the winding phase sequence switching are performed according to the requirements of the given truth table. Different design definitions of the drive circuit (winding phase sequence, Hall device level, etc.) will also affect whether the motor can rotate normally.

[0010] Starting from the needs of the motor drive control system, the specified rotation direction is given, and according to the requirements of the drive circuit, the winding switching phase sequence and order, and the Hall output state are given, that is, the required truth table and winding and Hall color definition requirements are given. How to judge whether the winding and Hall phase sequence and color of the brushless DC motor can meet the requirements of the truth table is the problem we need to solve. At present, the main solution is to conduct trial and error with the drive circuit, and repeated tests are required before the motor can rotate normally, but it is still difficult to judge whether the requirements of the truth table are truly met at this time. Most motor drive control systems will choose brushless DC motors or drive circuits from different manufacturers, or only require brushless DC motors, which also causes trouble for whether the manufactured brushless DC motors meet the overall technical requirements. Whether the winding phase sequence and Hall phase sequence of the motor can meet the established technical requirements is the problem we need to solve. Summary of the invention

[0011] In view of the deficiencies in the prior art, the present invention provides a method for determining and correcting the Hall and winding phase sequence of a brushless DC motor that is independent of a drive circuit.

[0012] The purpose of the present invention is achieved through the following technical means:

[0013] A method for determining and correcting the Hall and winding phase sequence of a brushless DC motor comprises the following steps: 1. constructing a circuit for determination and correction, wherein the circuit comprises three (1-10) kΩ resistors, a first DC regulated power supply, a second DC regulated power supply, an oscilloscope with more than three channels, connecting cables and a manufactured three-phase brushless DC motor; the power supply VCC of three Hall elements of the brushless DC motor is connected to the positive electrode of the first DC regulated power supply, the ground GND of the three Hall elements is connected to the negative electrode of the first DC regulated power supply, and the power supply is 5V-12V; the output Vout ends of the three-phase Hall elements HA, HB and HC are respectively connected to the positive electrode of the first DC regulated power supply through a 1 kΩ-10 kΩ resistor, and the output HA, HB and HC of the three-phase Hall elements and the ground GND are respectively connected to the positive and negative wiring terminals of the oscilloscope probe; two phases of the three-phase winding lead wires A, B and C are respectively connected to the positive and negative electrodes of the second DC regulated power supply.

[0014] Step 2: Determine and correct the phase sequence and color of the three-phase winding and the phase sequence and color of the three-phase Hall through the constructed determination and correction circuit.

[0015] According to the given A, B, C phase colors in the truth table, the second DC regulated power supply is used to supply power to the two-phase windings in sequence according to the specified switching order, and the motor rotates intermittently in the required direction of rotation according to the state sequence specified in the truth table, indicating that the motor A, B, C phases and colors meet the requirements of the truth table. Then, for any state m in the truth table (m is the value in the table), The two-phase winding of the next state m+1 (if m+1>6, then take m+1-6=m-5 state) is powered, and after the motor stops rotating, the power supply state is maintained, and the levels of HA (S4), HB (S5), and HC (S6) are detected, which are consistent with the Hall level corresponding to the next state m+2 (if m+2>6, then take m+2-6=m-4 state) in the truth table; continue to power the two-phase winding of the next state m+2, and after the motor stops rotating, detect the levels of HA (S4), HB (S5), and HC (S6), which are consistent with the Hall level corresponding to the next state m+3 (if m+3>6, then take m+3-6=m-3 state) in the truth table; proceed in sequence according to the above rules to complete the power supply of the two-phase winding corresponding to the six states. The Hall levels detected after stopping are consistent with the Hall levels of the next switching state in the truth table, indicating that the phase sequence of HA, HB, and HC and the corresponding colors meet the requirements of the truth table;

[0016] If the two-phase windings in the truth table are powered in sequence, and the direction of rotation of the motor is opposite to the requirements in the truth table, it is determined that the ABC phase sequence does not meet the requirements of the truth table; then swap any two phases in ABC, and the colors will be in accordance with the requirements of the truth table to form a new ABC; then power the two-phase windings in the truth table in sequence according to the new ABC, and the direction of rotation of the motor is the same as the requirements in the truth table. The two-phase winding of the next state m+1 (if m+1>6, then take m+1-6=m-5 state) is powered, and after the motor stops, the levels of HA (S4), HB (S5), and HC (S6) are detected, and the number of "0, 1" in the level should be equal to the number of "0, 1" in the next state m+2 (if m+2>6, then take m+2-6=m-4 state), and the different one of the three levels is assigned to the corresponding Hall and the corresponding color according to the next state m+2; continue to power the two-phase winding of the next state m+2 (if m+2>6, then take m+2-6=m-4 state), and after the motor stops, the levels of HA (S4), HB (S5), and HC (S6) are detected, and one of the levels with the same state as above has a jump. According to the truth table, the one with the jump level is assigned to the corresponding Hall and the corresponding color, and the remaining Hall and color are also determined, so that correction is achieved.

[0017] Moreover, first determine the winding phase sequence and set the power supply in sequence of B+C-, B+A-, C+A-, C+B-, A+B-, and A+C-. If the motor rotates to a fixed position in the first step and then commutates five times, the motor rotates counterclockwise, which meets the given requirements, indicating that the phase sequence of the three-phase winding is correct. Specifically, the B phase (S2) is connected to the positive pole of the power supply, and the C phase (S3) is connected to the negative pole of the power supply. The power supply is supplied by B(S2)+ and C(S3)-. The motor rotor rotates to a fixed position. The winding power supply phase is changed to B(S2)+ and A(S1)-. The motor should rotate counterclockwise and then stop. The power supply phase is changed to C(S3)+ and A(S1)-. The motor should continue to rotate counterclockwise and then stop. The power supply phase is changed to C(S3)+ and B(S2)-; A(S1)+ and B(S2)-; A(S1)+ and C(S3)-; B(S2)+ and C(S3)- in sequence. The motor should rotate counterclockwise and then stop. According to the winding power supply phase sequence and the corresponding power supply sequence specified in the truth table specified above, the motor rotates intermittently in the same direction according to the specified direction, which indicates that the phase sequence of the three-phase winding is correct. If the formed winding magnetomotive force rotates clockwise, the motor rotates clockwise, which does not meet the given requirements, then swap two phases of A, B, and C, and then set the power supply in order of B+C-, B+A-, C+A-, C+B-, A+B-, and A+C- according to the new A(S1), B(S2), and C(S3), and the motor rotates counterclockwise in the correct direction, completing the determination and correction of the phase sequence and color of the three-phase winding;

[0018] Determine the phase sequence of the three-phase Hall: At any position of the rotor, the stator winding B phase (S2) is connected to the positive pole of the power supply, and the C phase (S3) is connected to the negative pole of the power supply, that is, the power supply is B (S2) +, C (S3) -, and the motor rotor rotates to a fixed position; then the power supply phase is changed to B (S2) +, A (S1) -, the motor should rotate counterclockwise, and then stop, keeping the power supply state. At this time, the oscilloscope is used to measure the three-phase Hall HA (S4), HB (S5), HC (S6) levels should be (100). If the relationship does not correspond, the oscilloscope measures the three-phase Hall levels as two low levels "0" and one high level "1". The Hall corresponding to the high level is designated as HA, assuming that it is color Color S5, the Hall corresponding to the low level "0" is to be determined; change the power supply phase to C(S3)+, A(S1)-, the motor should rotate counterclockwise and then stop, then one of the two previously undefined 0s will jump to 1, and the Hall corresponding to the color that jumps to high level 1 will be designated as HB, assuming it is color S6, and the remaining one is HC, color S4; then color S5 represents HA, color S6 represents HB, and color S4 represents HC, which is inconsistent with the truth table. Based on the fact that HA, HB, and HC have been identified by the corresponding colors, replacement is performed to replace S5 (HA) with S4, and S6 (HB) with S5; color S4 (HC) is replaced with S6 to meet the requirements of the truth table.

[0019] Table 3 Power supply sequence and position signal discrimination table of each phase winding (viewed from the shaft extension end, the motor shaft rotates counterclockwise)

[0020]

[0021] The advantages and positive effects of the present invention are:

[0022] 1. The present invention does not rely on the driving control circuit, but relies on a simple circuit built with three resistors of (1-10) kΩ, an oscilloscope device with no less than three channels, two DC regulated power supplies, and connecting cables. The windings, Hall phase sequence, and color of the motor are independently identified and judged to see whether they meet the established technical requirements of the truth table, thus achieving isolation of technical problems and compliance with technical requirements;

[0023] 2. For the first motor prototype or the first batch of motors, the phase sequence and color of the winding and Hall are determined and corrected according to the method of the present invention, and specific color and phase sequence requirements are given for the motor stator winding, Hall circuit board or Hall pin welding to ensure that the phase sequence and color of the motor winding and Hall produced meet the overall design technical requirements. This avoids the need to match the manufactured motor with the drive circuit or hand it over to the overall system for the determination of the phase sequence and color of the winding and Hall, saves the development time of the motor project, avoids unnecessary coordination and communication, and even quality problems. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is the Hall, winding phase sequence and color detection test diagram of the present invention;

[0025] Figure 2 It is a flow chart of conformity detection of phase sequence and color of three-phase windings A, B and C of the present invention;

[0026] Figure 3 The following is a flow chart of the conformity detection of windings, Hall phase sequence and colors of the present invention;

[0027] Figure 4 The present invention is a flow chart of the correction and determination of the phase sequence and color of the winding and the Hall;

[0028] Figure 5 It is a schematic diagram of the phase sequence and color exchange of the winding and Hall of the present invention;

[0029] Figure 6 is an output characteristic diagram of the switch Hall device of the present invention;

[0030] Figure 7 The magnetomotive force and linear magnetomotive force distribution diagram of the three-phase windings A, B and C of the present invention;

[0031] Figure 8 It is a schematic diagram of the present invention with a driving circuit in switching states Ⅰ and Ⅱ;

[0032] Fig. 9 This is a state diagram of the present invention when the non-driving circuits B+ and C- are powered on without switching and continue to rotate and stop;

[0033] Fig.10 It is a schematic diagram of overshoot and reverse torque application after B+ and C- power supply stop of the present invention;

[0034] Fig.11 It is a schematic diagram of the alignment and rotation of the scoring lines between the stator and rotor of the present invention.

[0035] The names and part numbers of the components in the attached drawings are as follows:

[0036] A first DC regulated power supply 1; a second DC regulated power supply 2; a pull-up resistor 3-1; a pull-up resistor 3-2; a pull-up resistor 3-3; a channel 1 probe 4-1 of an oscilloscope; a channel 2 probe 4-2 of an oscilloscope; a channel 3 probe 4-3 of an oscilloscope; a brushless DC motor M 5; a HA Hall 5-1 of the brushless DC motor M; a HB Hall 5-2 of the brushless DC motor M; and a HC Hall 5-3 of the brushless DC motor M. DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. The following embodiments are only illustrative and not restrictive, and the protection scope of the present invention cannot be limited thereto.

[0038] In the specific embodiments of the present invention, in order to better describe the implementation method and process, a restrictive description is made for the brushless DC motor and its position sensor, which does not exclude other types of brushless DC motors and other types of position sensors. The present invention does not limit the detailed design and structure inside the brushless DC motor, but it should comply with the general electromagnetic principles of the brushless DC motor, and its structural type and technical solution only need to meet the relevant requirements of the embodiments of the present invention.

[0039] like Figure 1 As shown, the VCC power supplies of the HA Hall 5-1, HB Hall 5-2, and HC Hall 5-3 of the brushless DC motor 5 are connected to the positive electrode of the first DC regulated power supply 1; the ground GND of the HA Hall 5-1, HB Hall 5-2, and HC Hall 5-3 of the brushless DC motor 5 is connected to the negative electrode of the first DC regulated power supply 1; the pull-up resistors 3-1, 3-2, and 3-3 are connected in series between the output Vout of the HA Hall 5-1, HB Hall 5-2, and HC Hall 5-3 of the brushless DC motor 5 and the positive electrode of the first DC regulated power supply 1, respectively, the positive and negative electrodes of the oscilloscope probe 4-1 are connected to the Vout and GND of the HA Hall 5-1, the positive and negative electrodes of the oscilloscope probe 4-2 are connected to the Vout and GND of the HB Hall 5-2, and the positive and negative electrodes of the oscilloscope probe 4-3 are connected to the Vout and GND of the HC Hall 5-3. According to the general requirements of the current Hall device, the voltage of the first DC regulated power supply 1 is 5V to 12V, and the pull-up resistors 3-1, 3-2, and 3-3 have the same value, which is 1kΩ to 10kΩ. The three-phase windings A, B, and C of the brushless DC motor are connected to the positive and negative electrodes of the second DC regulated power supply 2 according to the needs and requirements of the test steps and processes.

[0040] For the sake of explanation, a Hall truth table technical requirement is taken as shown in Table 2, which has universal significance. The specific judgment and correction process is as follows Figure 2 , Figure 3 , Figure 4 shown.

[0041] exist Figure 2 In the process, the two-phase windings of the specified colors are powered in sequence according to the Ⅰ→Ⅵ→Ⅰ states specified in the truth table. If the motor rotors rotate in the same direction as required by the truth table, it indicates that the phase sequence and corresponding colors of the three-phase windings are correct.

[0042] exist Figure 3In the process, under the premise that the winding phase sequence and color are correct, the power supply is also provided in the specified Ⅰ→Ⅵ→Ⅰ state. When the power supply is completed and maintained, the rotor stops rotating and the Hall level is detected. According to the truth table, the Hall levels of the color and phase sequence are the same as the levels corresponding to the next state, indicating that the phase sequence and corresponding colors of the three-phase Hall are correct.

[0043] exist Figure 4 In the process, power is supplied according to the state Ⅰ→Ⅱ. If the rotation direction is found to be incorrect, the colors of B and C are swapped to form a new ABC. The motor rotation direction is correct. Under the premise that the motor rotation direction is correct, the Hall phase sequence and color are judged. According to the principle of Hall jump, the Hall corresponding to the color with different levels is first confirmed, and then the Hall with state jump is determined. After the three Halls are confirmed by the corresponding colors, they are replaced with the specified correct colors according to the requirements of the truth table.

[0044] It should be noted that:

[0045] a) The two-phase winding is powered. After the rotor stops, the power supply should continue. At this time, an oscilloscope is used to detect the Hall level.

[0046] b) When detecting the Hall level, in order to prevent false detection, a certain torque opposite to the rotor rotation direction can be manually applied to the rotating shaft. The applied torque can be manually maintained or slowly released manually. However, it is better to manually maintain the applied torque. At this time, the detection level is accurate.

[0047] c) Two-phase winding power supply, the power supply voltage should not be too large. Assuming the friction torque of the motor is f (Nm), the torque coefficient of the motor is km (Nm / A), and the line resistance of the motor is Rx (Ω), the applied voltage is recommended to be:

[0048]

[0049] d) The state of Ⅰ→VI in the truth table is forward-circulating, that is, the next state of Ⅰ is Ⅱ, and the next state of Ⅱ is

[0050] Ⅲ, the next state of Ⅲ is Ⅳ, the next state of Ⅳ is Ⅴ, the next state of Ⅴ is Ⅵ, and the next state of Ⅵ is Ⅰ.

[0051] e) The phase sequence swapping mentioned above should be processed at the source end, that is, swap the output end and the lead wire of the motor armature winding to form a new ABC phase specified by the truth table color; the same is true for the Hall phase sequence, which needs to be swapped at the output end of the Hall terminal board or the Hall pin to form a new HA, HB, HC phase specified by the truth table color. Figure 5 As shown, in this way, windings A, B, C and HA, HB, HC with the phase sequence and colors specified in the truth table can be formed.

[0052] f) The marking lines between the stator and rotor can be drawn with a marking pen or other means. The marking lines should be easy to observe, such as between the inner and outer rings of the bearing, between the housing and the shaft, and can logically represent the relative rotation direction between the stator and rotor on the observation side of the truth table.

[0053] g) The truth table of Example Table 2 is not unique and meets the Figure 7 The relationship between the phase winding magnetomotive force, the line magnetomotive force, and the Hall position in the embodiment of the present invention can be as long as it meets the requirements of the law of the truth table. This implementation process has universal significance.

[0054] The specific working principle of the present invention is:

[0055] First, let's explain the principle and meaning of the truth table in Table 2:

[0056] For a three-phase brushless DC motor, there are six conduction states, namely, the conduction phases BC, BA, CA, CB, AB, and AC in Table 2. The Hall output has six valid states. When the drive circuit recognizes a certain state, such as I (001), the drive circuit switches the winding B→C to conduct. When the Hall level state changes once, such as II (101), the drive circuit switches the winding to B→A. Following the requirements of Table 2, the Hall state changes are recognized in turn, and the corresponding two-phase windings are switched to conduct. The armature magnetic field jumps in one direction at an electrical angle of 60°, and the rotor is dragged to rotate continuously in one direction. Furthermore, state I→VI represents a cycle of winding power-on, with an electrical angle of 360°. The combination of the Hall level in each state can only be two "0", one "1" or two "1", one "0"; each Hall level "1" and "0" needs to maintain three working states, that is, 180° electrical angle. When switching from state I to state VI in turn, the Hall level in the previous state does not jump when the adjacent switching state is switched. For example, in the table, the HC level in state I is "1"; the HB level in state II is "0"; the HA level in state III is "1"; the HC level in state IV is "0"; the HB level in state V is "1"; and the HA level in state VI is "0".

[0057] For the provisions of the Hall level, such as Figure 6As shown. Currently, most mainstream manufacturers define that when the S pole of the permanent magnet faces the Hall integrated current sign surface, the magnetic flux density is defined as positive. When the permanent magnet magnetic flux density is positive and greater than the action value Bop, the Hall integrated circuit outputs Uout as a low level. When the magnetic flux density is negative and less than the return value Brp, the Hall integrated circuit outputs a high level. The output waveform duty cycle is close to 1:1. There is a hysteresis loop between Bop and Brp, and its value is very small. The values ​​of Bop and Brp are generally around tens of Gauss. It is generally believed that when the switch latch type Hall integrated circuit sign surface faces the S pole of the permanent magnet, its output is 0; when the switch latch type Hall integrated circuit sign surface faces the N pole of the permanent magnet, its output is 1.

[0058] For the manufactured motor, first assume that the three-phase windings of the motor are 120° electrical angle apart in the circumferential space, and the Hall is also arranged at 120° electrical angle apart in the circumferential space. The relative position relationship between the Hall and the winding is arranged on the magnetomotive force axis according to the requirements of Table 1. The abstract windings A, B, C and HA, HB, HC are represented by corresponding specified colors or logos.

[0059] like Figure 7 As shown in the figure, the three-phase permanent magnet brushless DC motor consists of a rotor and a stator. Any motor can be simplified into a physical model of a pair of poles and six slots. A, x; B, y; C, z represent three-phase windings, which are evenly distributed in the space at an electrical angle of 120°. When two phases of the three-phase winding are energized, the stator forms a linear magnetic motive force, as shown in Figure F. BC 、F BA 、F CA 、F CB 、F AB 、F AC There are only two ways for ABC to be distributed in space. Figure 7 (a), the space is distributed clockwise as Figure 7 (b) As shown in the truth table, the two-phase windings are switched in turn, which is essentially the switching process of the line magnetomotive force, as shown in Figure 7 In (a), when B+ and C- supply power, a linear magnetomotive force F is formed. BC Under the action of magnetomotive force, according to the principle of attraction between N and S poles, the magnetic poles of the permanent magnet rotor are directed to F BC Alignment, that is, the permanent magnet N pole is aligned F BC Axis, as shown Fig.11 When the switch is B+ and A-, the line magnetomotive force rotates 60° counterclockwise, and the permanent magnet rotor is forced to rotate counterclockwise until it is aligned with F. BA When the winding power supply is switched in sequence, the permanent magnet rotor will follow the jumping direction of the linear magnetomotive force and realize rotation. Figure 7(a), ABC is counterclockwise distributed, forming a corresponding linear magnetic motive force, and BCA is also counterclockwise distributed, forming a corresponding linear magnetic motive force. The two are equivalent, and CAB is also equivalent. Figure 7 (b), ACB, CBA, and BAC are also equivalent. For the manufactured motor, according to the established truth table switching requirements, such as Figure 7 In (a), F BC 、F BA 、F CA 、F CB 、F AB 、F AC The rotor rotates counterclockwise. Figure 7 (b), then it rotates clockwise. If the switching sequence given in Table 2 is followed, the motor rotates clockwise, which does not meet the requirements of the truth table. Figure 7 As shown in (b), we need to swap the two phases in ABC. Assuming it is BC, the resulting linear magnetomotive force is as follows: Figure 7 As shown in (a), the rotor will rotate counterclockwise, which meets the requirements of the truth table. The above is the basic principle of changing the rotation direction of the motor by swapping two of the phases ABC. Interestingly, for a given three-phase winding phase sequence and color, if the switching order in the truth table is changed, the rotation direction can also be changed, such as Figure 7 (b) Press F CB 、F CA 、F BA 、F BC 、F AC 、F AB , then counterclockwise rotation is achieved, such as Figure 7 (a), press F CB 、F CA 、F BA 、F BC 、F AC 、F AB , then clockwise rotation is achieved, but this requires changing the truth table design technical requirements.

[0060] The following is a detailed description of the Hall level correspondence between the switching with a drive circuit and the switching without a drive circuit when two-phase power supply is used. Figure 8 As shown in (a), when there is a driving circuit, when it is detected that HB jumps from 1 to 0, the three Hall levels are (001), and the driving circuit switches to B+ and C- to form a linear magnetomotive force F BC , which drags the rotor to rotate counterclockwise. After rotating 60° electrical angle, the level of HA will jump from 0 to 1. At this time, the drive circuit will switch to B+ and A- to be powered, and the Hall level is (101). Figure 8Assume that the drive circuit does not switch at this moment and keeps B+ and C- powered, the rotor will continue to rotate counterclockwise and the level will remain at (101), as shown in Fig. 9 (a) until the rotor poles meet F BC Aligned, the Hall level is always kept at (101), such as Fig. 9 (b) As shown. It can be seen that in state Ⅰ, power is supplied to B+ and C-, and there is no switching without a drive circuit. The rotor rotates in the required direction, and the level after stopping is consistent with the level of state Ⅱ with a drive circuit. In other words, if there is no drive circuit, the winding in state m is powered according to the corresponding phase sequence, and the Hall level after the rotor stops should be consistent with the level of state m+1 in the truth table, which provides a method for Hall level determination. It should be noted that when power is supplied to B+ and C-, the rotor poles are in contact with F BC After alignment, the rotor poles are aligned with F BC There is attraction between N and S, which means the rotor magnetic pole position is located and the Hall level remains unchanged. Fig. 9 In (b), the Hall HC is just at the junction of the N and S poles, and is about to jump and form a level (100), which is consistent with the level of state III in the truth table. This situation may also occur in actual operation. When B+ and C- are powered by a large current, the rotor may overshoot, such as Fig.10 As shown in (a), the Hall level is (100), which is consistent with the level of state III. This is an uncertain state. To avoid wrong judgment, in actual operation, the rotor can be manually torqued in the reverse direction of rotation, and the torque state can be maintained or released. Then the Hall level is (101), as shown in Fig.10 (b) As shown in the figure, for the "released" state, the explanation for the HC level being "1" is that the torque is applied in the reverse direction of rotation. After release, due to the friction torque (magnetic damping torque and mechanical friction torque) between the stator and the rotor, the rotor magnetic pole boundary line on the HC side is BCThe angle between the axis of the linear magnetomotive force is slightly larger than the 90° electrical angle, and HC is still under the N pole. Although the magnetic field is small, the sensitive magnetic field of the Hall is very small, so the level of HC is "1". The above shows that when the power is supplied according to the winding and phase sequence of the m state, after the rotor stops, the Hall level is consistent with the Hall level of the m+1 state. To ensure this result, the rotor can be torqued in the reverse direction of rotation manually and kept re-detected. If the levels detected by the colors corresponding to HA, HB, and HC in the truth table are inconsistent in combination (note that the number of "1" and "0" is consistent with the state m+1), the color with different levels is assigned to the corresponding Hall according to the state m+1. For example, for m=Ⅰ, power is supplied to B+ and C-, the rotor stops rotating and is positioned, power is supplied to the state (m+1=Ⅱ), that is, B(S2)+, A(S1)-, the motor should rotate counterclockwise, and then stop. Assuming that the corresponding levels of the color lead wires of S4, S5, and S6 are detected to be 0, 1, and 0 respectively, the color S5 is assigned to HA (level 1); continue to supply power to the winding of the state (m+2=Ⅲ), that is, C(S3)+, A(S1)-, after the rotation stops, one of S4 and S6 jumps from "0" to "1", assuming it is S6, then S6 is assigned to HB, and the remaining color S4 is assigned to HC. That is to say, color S5 represents HA, color S6 represents HB, and color S4 represents HC, which does not meet the requirements of the truth table. Replace according to the requirements of the truth table, S4→S5(HA); S5→S6(HB); S6→S4(HC). That is, the correction of the Hall color of the truth table is completed. According to the above determination method, the Hall phase sequence and color determination test verification can be carried out again according to the calibrated HA, HB, and HC.

[0061] The above description is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be applied to other combinations, modifications and environments. Changes and modifications made by those skilled in the art do not depart from the scope of the present invention and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A method for determining and correcting the Hall and winding phase sequence of a brushless DC motor, characterized in that: Step 1, build a circuit for determination and correction, the circuit includes three (1-10) kΩ resistors, a first DC regulated power supply, a second DC regulated power supply, an oscilloscope with more than three channels, connecting cables and a manufactured three-phase brushless DC motor; the power supply VCC of the three Hall elements of the brushless DC motor is connected to the positive electrode of the first DC regulated power supply, and the ground terminals GND of the three Hall elements are connected to the negative electrode of the first DC regulated power supply, and the power supply is 5V-12V; the output Vout terminals of the three-phase Hall HA, HB, and HC are respectively connected to the positive electrode of the first DC regulated power supply through a 1kΩ-10kΩ resistor, and the output HA, HB, HC and the ground terminal GND of the three-phase Hall are respectively connected to the positive terminal and the negative terminal of the oscilloscope probe; two phases of the three-phase winding lead wires A, B, and C are respectively connected to the positive and negative electrodes of the second DC regulated power supply; Step 2: Determine and correct the phase sequence and color of the three-phase winding and the phase sequence and color of the three-phase Hall through the constructed determination and correction circuit.

2. The method for determining and correcting the Hall and winding phase sequence of a brushless DC motor according to claim 1, characterized in that: Step 2 includes: According to the given A, B, C phase colors in the truth table, according to the specified switching order, the two-phase windings are powered in sequence through the second DC power supply, and according to the state sequence specified in the truth table, the motor rotates intermittently in the required rotation direction, which indicates that the motor A, B, C phases and colors meet the requirements of the truth table; then power is supplied to the two-phase windings of any state m in the truth table, and then power is supplied to the two-phase windings of the next state m+1. After the motor stops rotating, the power supply state is maintained, and the levels of HA, HB, and HC are detected, which are consistent with the Hall levels corresponding to the next state m+2 in the truth table; continue to power the two-phase windings of the next state m+2. After the motor stops rotating, the levels of HA, HB, and HC are detected, which are consistent with the Hall levels corresponding to the next state m+3 in the truth table; proceed in accordance with the above rules in sequence, complete the power supply of the two-phase windings corresponding to the six states, and the Hall levels detected after stopping are consistent with the Hall levels of the next switching state in the truth table, which indicates that the HA, HB, and HC phase sequence and the corresponding colors meet the requirements of the truth table; If the two-phase windings in the truth table are powered in sequence, the rotation direction of the motor is opposite to the requirement in the truth table, and it is determined that the requirements of the truth table are not met in the ABC phase sequence discrimination; then any two phases in ABC are swapped, and the colors are in accordance with the requirements of the truth table to form a new ABC; then the two-phase windings in the truth table are powered in sequence according to the new ABC, and the rotation direction of the motor is the same as the requirement in the truth table; power the two-phase windings in any state m in the truth table, and then power the two-phase windings in the next state m+1. After the motor stops, detect the levels of HA, HB, and HC. The number of "0, 1" in the level should be equal to the number of "0, 1" in the next state m+2. The different one of the three levels is assigned to the corresponding Hall and the corresponding color according to the next state m+2; continue to power the two-phase windings in the next state m+2. After the motor stops, detect the levels of HA, HB, and HC. If one of the levels in the same state has a jump, according to the truth table, the one with the jump is assigned to the corresponding Hall and the corresponding color, and the remaining Hall and color are also determined, and correction is achieved.

3. The method for determining and correcting the Hall and winding phase sequence of a brushless DC motor according to claim 2, characterized in that: First, determine the winding phase sequence, and set the power supply in sequence of B+C-, B+A-, C+A-, C+B-, A+B-, and A+C-. If the motor rotates to a fixed position in the first step, and then rotates counterclockwise for the next five commutations, it meets the given requirements, indicating that the phase sequence of the three-phase winding is correct. Specifically: Connect the B phase to the positive pole of the power supply, connect the C phase to the negative pole of the power supply, and supply power according to B+ and C-. When the motor rotor rotates to a fixed position, change the winding power supply phase to B+ and A-. The motor should rotate counterclockwise and then stop. Change the power supply phase to C+ and A-. The motor should continue to rotate counterclockwise and then stop. Change the power supply phase to C+ and B-; A+ and B-; A+ and C-; B+ and C- in sequence. The motor should rotate counterclockwise and then stop. According to the winding power supply phase sequence specified by the truth table above, and the corresponding In the power supply sequence, the motor rotates in the same direction intermittently according to the specified direction, which indicates that the phase sequence of the three-phase winding is correct; if the formed winding magnetomotive force rotates clockwise, the motor rotates clockwise, which does not meet the given requirements, then swap two phases of A, B, and C, and then set the power supply in order of B+C-, B+A-, C+A-, C+B-, A+B-, and A+C- according to the new A, B, and C. The motor rotates counterclockwise in the correct direction, and the determination and correction of the phase sequence and color of the three-phase winding are completed; Determine the phase sequence of the three-phase Hall: At any position of the rotor, the B phase of the stator winding is connected to the positive pole of the power supply, and the C phase is connected to the negative pole of the power supply, that is, the power supply is B+ and C-, and the motor rotor rotates to a fixed position; then the power supply phase is changed to B+ and A-, the motor should rotate counterclockwise, and then stop and keep the power supply state. At this time, the oscilloscope is used to measure the levels of the three-phase Hall HA, HB, and HC, which should be (100). If the relationship does not correspond, the oscilloscope measures the levels of the three-phase Hall as two low levels "0" and one high level "1". The Hall corresponding to the high level is designated as HA, assuming color S5, and the low level " The Hall corresponding to "0" is to be determined; change the power supply phase to C+ and A-, the motor should rotate counterclockwise and then stop. Then one of the two undefined 0s will jump to 1, and the Hall corresponding to the color that jumps to high level 1 is designated as HB, assuming color S6, and the remaining one is HC, color S4; then color S5 represents HA, color S6 represents HB, and color S4 represents HC, which is inconsistent with the truth table. Based on the fact that HA, HB, and HC have been identified by the corresponding colors, they are replaced, so that S5 is replaced by S4, S6 is replaced by S5; color S4 is replaced by S6, so as to meet the requirements of the truth table.

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