High-reliability axial magnetic field permanent magnet brushless motor

Abstract

The high-reliability axial magnetic field permanent magnet brushless motor provided by the utility model theoretically and technically solves the problem of motor burnout caused by phase loss of a three-phase permanent magnet brushless motor, and the reliability of the three-phase permanent magnet brushless motor is greatly improved. For a widely used axial magnetic field three-phase permanent magnet brushless motor, in the on-load operation process of the brushless motor driven by the high-reliability axial magnetic field permanent magnet brushless motor provided by the invention, when phase loss occurs, the input power is automatically reduced, the rotating speed is reduced, and the brushless motor cannot be burnt out after long-time operation; and in addition, the system can be restarted after phase loss and rotation stop, and original performance can be recovered when phase loss is avoided. The motor manufacturing process, cost and performance are the same as those of an original motor. The method has wide application prospects in military, aviation, spaceflight, new energy ships, new energy automobiles and other places requiring high reliability.

Description

[0001] The invention discloses a high-reliability axial magnetic field permanent magnet brushless motor, which comprises a brushless motor and a brushless motor driver circuit. Technical Field

[0002] The present invention relates to the technical field of brushless motors and brushless motor driver circuits. Background Art

[0003] The brushless motor consists of a motor body and a driver circuit and is a typical mechatronics product.

[0004] In the past, three-phase permanent magnet brushless motors, like three-phase AC induction motors, typically burned out when a phase loss occurred in the motor windings. Data from major brushless motor manufacturers indicates that phase loss accounts for approximately 20% of brushless motor burnouts. However, in the military, aviation, and aerospace industries, high reliability demands necessitate the use of six-phase brushless motors to mitigate performance degradation in the event of a phase loss. However, six-phase brushless motors introduce new challenges in both manufacturing and driver development, and the increased number of phases in the motor also reduces the desired speed. Summary of the Invention

[0005] The present invention provides a high-reliability axial magnetic field permanent magnet brushless motor, which theoretically and technically solves the problem of motor burnout caused by phase loss in axial magnetic field three-phase permanent magnet brushless motors, and greatly improves the reliability of axial magnetic field three-phase permanent magnet brushless motors. For the widely used double-slot and single-slot axial magnetic field three-phase permanent magnet brushless motors, the brushless motor driven by the high-reliability axial magnetic field permanent magnet brushless motor provided by the present invention will not burn out even if a phase loss occurs during long-term operation during load operation, and can restart after stopping rotation and restore its original performance when there is no phase loss. Its motor manufacturing process, cost and motor performance are the same as those of the original motor. The magnetic fields of the motor stator and rotor are parallel to the motor shaft, so it is named a high-reliability axial magnetic field permanent magnet brushless motor.

[0006] The high-reliability axial magnetic field permanent magnet brushless motor of the present invention adopts a mode in which the magnetic force lines of the stator and rotor are parallel to the motor shaft, and the plane on which the permanent magnets on the rotor are installed is perpendicular to the rotor shaft.

[0007] The driver circuit of the high-reliability axial magnetic field permanent magnet brushless motor of the present invention is composed of a PWM pulse width modulator with adjustable speed control, which is implemented by a microcontroller MCU, and an H-bridge power driver (generally a high-power MOS tube or IGBT composite fully controlled voltage-driven power semiconductor device module) that drives the winding coils of each phase. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1It is a schematic diagram of the motor structure of the high-reliability axial magnetic field permanent magnet brushless motor of the present invention.

[0009] Figure 2 This is a stator winding diagram of a double-slot motor with 4 rotor poles and 24 stator slots. The arrows on the line represent the winding direction of the coils on the winding.

[0010] Figure 3 This is a stator winding diagram of a single-slot motor with 4 rotor poles and 12 stator slots. The arrows on the line represent the winding direction of the coil on the winding.

[0011] Figure 4 yes Figure 2 Another stator winding diagram of a double-slot motor made with a 24-slot stator, which is located on the other side of the rotor.

[0012] Figure 5 yes Figure 3 Another stator winding diagram of a single-slot motor made with a 12-slot stator, which is located on the other side of the rotor.

[0013] Figure 6 For clarity only Figure 2 The winding diagram of the U-phase winding above shows the magnetic pole magnetism on each armature tooth when the current is input by A+ and output by A-.

[0014] Figure 7 For clarity only Figure 3 The winding diagram of the U-phase winding above shows the magnetic pole magnetism on each armature tooth when the current is input by A+ and output by A-.

[0015] Figure 8 This is a schematic diagram of a 4-pole motor rotor.

[0016] Figures 9 to 20 This is a driving diagram of a high-reliability axial magnetic field permanent magnet brushless motor in various normal driving states.

[0017] Figures 21 to 32 This is a driving diagram of a high-reliability axial magnetic field permanent magnet brushless motor in various driving states when the U-phase winding is missing.

[0018] Figure 33 This is the main control diagram of the driver circuit for a high-reliability axial-field permanent magnet brushless motor.

[0019] Figure 34 This is the power output circuit diagram of the driver circuit of a high-reliability axial magnetic field permanent magnet brushless motor. DETAILED DESCRIPTION

[0020] A high-reliability axial magnetic field permanent magnet brushless motor comprises a motor and its driver circuit. Its characteristics are as follows: the stator plane of the high-reliability axial magnetic field permanent magnet brushless motor is perpendicular to the motor shaft. The stator, made of magnetic conductive material, is radially structured with armature teeth for winding stator coils. The plane formed by the armature teeth is perpendicular to the motor shaft. Armature slots for winding three-phase physical windings are located between the armature teeth on the stator. When powered, an axial magnetic field is generated. The mounting plane of the permanent magnets on the rotor is also perpendicular to the motor shaft. Its magnetic lines of force are distributed axially along the motor shaft. The north and south poles of the permanent magnets are arranged adjacent to each other, generating an axial magnetic field. The stator coils are wound in a distributed manner with a certain number of armature tooth slots spaced apart. Adjacent coils of the same phase winding are wound in opposite directions, and the windings of each phase are placed a certain distance apart. Its driver circuit uses three sets of H-bridge power drivers, and the two ends of each phase winding on the stator are respectively connected to their own H-bridge power drivers.

[0021] The relationship between the number of magnetic poles on the permanent magnet rotor of the high-reliability axial magnetic field permanent magnet brushless motor, the number of phases of the stator winding, and the number of armature slots on the stator per side is: the number of armature slots on the stator per side is equal to the sum of the south poles and north poles of the permanent magnets on the rotor per side multiplied by the number of phases of the stator winding 3 and then multiplied by the slot number K. When the slot number K is equal to 1, it is a single-slot structure, and when the slot number K is equal to 2, it is a double-slot structure.

[0022] In a single-slot structure with a slot multiplication number K equal to 1, in a high-reliability axial magnetic field permanent magnet brushless motor, when the number of armature slots on a single side of the stator is equal to the sum of the north and south magnetic poles on a single side of the permanent magnet rotor multiplied by the number of phases, the two adjacent coils of the same phase winding of the stator are wound in opposite directions, and when the armature teeth at the centers of the two adjacent coils are ignored, the centers of the two adjacent coils are separated by two armature teeth; when the armature teeth at the centers of the coils of the adjacent two-phase winding are ignored, the centers of the adjacent two-phase winding coils are separated by one armature tooth, and the starting end and the ending end of each phase winding are respectively connected to their own H-bridge power drivers.

[0023] In a double-slot structure with a slot multiplier K equal to 2, the number of armature slots on a single side of the stator of the high-reliability axial magnetic field permanent magnet brushless motor is equal to the sum of the north and south magnetic poles on a single side of the permanent magnet rotor multiplied by twice the number of phases. The two adjacent coils of the same phase winding of the stator are wound in opposite directions. When the armature teeth at the centers of the two adjacent coils are not counted, the centers of the two adjacent coils are separated by 5 armature teeth; when the armature teeth at the centers of the coils of the adjacent two-phase winding are not counted, the centers of the adjacent two-phase winding coils are separated by 3 armature teeth. The starting end and the ending end of each phase winding are respectively connected to their own H-bridge power drivers.

[0024] The installation plane of the permanent magnet on the rotor of the high-reliability axial magnetic field permanent magnet brushless motor is perpendicular to the motor shaft. The magnetic lines of force of the installed permanent magnet are distributed along the axial direction of the motor shaft, and the south and north poles of the permanent magnet are arranged adjacent to each other.

[0025] This high-reliability radial-field permanent magnet brushless motor features a driver circuit in which each phase winding's power driver consists of an H-bridge power driver consisting of two series-connected, fully-controlled, voltage-driven IGBT power semiconductor devices on the left arm and another series-connected, fully-controlled, voltage-driven IGBT power semiconductor device on the right arm. The starting and ending points of each phase winding are connected to the midpoints of the left and right arms of the H-bridge power driver. The upper and lower control terminals of each H-bridge power driver are controlled by four different signals. High-power MOS field-effect transistors and other high-power semiconductor devices can also be used as the power driver. The motor's rotor speed is regulated by a pulse-width modulated signal.

[0026] The high-reliability axial magnetic field permanent magnet brushless motor of the present invention has a stator slot count that is a multiple of the number of north and south magnetic poles of the permanent magnet rotor multiplied by the number of phases. When the single slot count K = 1, taking a three-phase winding with two pairs of four poles as an example, the number of slots is equal to 3 times 4 poles, which is 12 slots; if six pairs of 12 poles are used, the number is 36 slots. When the double slot count K = 2, taking a three-phase winding with two pairs of four poles as an example, the number of slots is equal to 3 times 4 poles, which is 12 slots, which is 24 slots; if six pairs of 12 poles are used, the number is 72 slots.

[0027] The stator windings of the high-reliability axial magnetic field permanent magnet brushless motor of the present invention are distributedly wound on a stator made of a magnetically conductive material, such as silicon steel sheets. The stator coils are wound between three armature teeth spanning at least two tooth slots, with adjacent coils of the same phase winding wound in opposite directions. This pattern of windings is maintained until the winding is complete. The two ends of each phase winding are connected to respective H-bridge power driver components of the high-reliability axial magnetic field permanent magnet brushless motor driver.

[0028] The power driving device that drives the winding to energize is composed of an IGBT composite fully controlled voltage driven power semiconductor device IGBT, and can also use high-power MOS field effect tubes and other high-power semiconductor power devices.

[0029] In brushless motors, the magnetic pole position on the rotor with permanent magnets is often detected by Hall elements. Alternatively, a disc with holes installed on the rotor shaft can be used in conjunction with a photoelectric element for detection. Alternatively, a rotary transformer can be used for detection. These are all commonly used detection technologies for the magnetic pole position on the permanent magnet rotor in brushless motors. Even Hall elements are divided into three types: latching, non-latching, and linear characteristics. For ease of understanding, the following is a brief introduction to the detection of the magnetic pole position on the rotor with permanent magnets. Figures 9 to 32The driving working principle and specific implementation method of the common Hall element with latch are explained.

[0030] Figure 1 This is a schematic diagram of the motor structure of an axial magnetic field DC permanent magnet brushless motor according to the present invention. 1 is a rotor, whose permanent magnet mounting plane is perpendicular to the motor shaft 7. The magnetic lines of force are distributed axially. S and N on 1 are the south and north poles of the permanent magnets, which are arranged with alternating north and south poles on the mounting plane. 2 is a stator made of a magnetically conductive material, whose stator plane is perpendicular to the motor shaft. The stator is constructed with armature teeth for winding stator coils. The plane formed by the armature teeth is also perpendicular to the motor shaft. Armature slots for winding the stator windings are located between the armature teeth. 3 are the end caps at both ends of the motor. 4 are bearings connecting the motor shaft and the end caps. 5 is the motor housing. 6 is the winding coil wound around the armature teeth on the stator.

[0031] Figure 2 It is a double-slot distributed winding. The coil is wound around 5 armature teeth. When the armature teeth in the middle of the winding coil are ignored, the distance between two adjacent winding coils of the same phase is 5 armature teeth. The distance between the centers of two adjacent phase windings is 3 armature teeth.

[0032] Figure 3 It is a single-slot distributed winding. The coil is wound around three armature teeth. When the armature tooth at the center of the winding coil is ignored, the centers of two adjacent winding coils of the same phase are separated by two armature teeth. The centers of two adjacent phase windings are separated by one armature tooth.

[0033] The arrows on the lines in these two figures indicate the winding direction, both of which are three-phase and four-pole.

[0034] Figure 4 and Figure 5 Another and Figure 2 and Figure 3 The schematic diagram of the stator on the other side of the rotor is opposite. Figure 1 It can be seen that it is located on the other side of the rotor, Figure 2 and Figure 3 The stator produces different magnetism under the same power-on driving state, driving the other side of the rotor to have different magnetism. The arrow in the figure also indicates the winding direction. For the sake of clarity, this part of the other side of the rotor will not be described later.

[0035] Figure 6 yes Figure 2 The double slot distributed winding only shows the winding method of the U phase. Figure 6It can be seen that the U-phase physical winding starts from U1, passes through the armature slot between the armature teeth 1 and 24 to the armature slot between the armature teeth 5 and 6, and is wound clockwise. Then, it goes to the armature slot between the armature teeth 11 and 12 to the armature slot between the armature teeth 6 and 7, and is wound counterclockwise (when the armature teeth 3 and 9 at the center of the coil are ignored, the centers of these two adjacent coils are separated by armature teeth 4, 5, 6, 7 and 8, totaling 5 armature teeth). Then, it goes to the armature slot between the armature teeth 12 and 13 to the armature slot between the armature teeth 17 and 18, and is wound clockwise (when the armature teeth 9 and 15 at the center of the coil are ignored, the centers of these two adjacent coils are separated by armature teeth 10, 11, 12, 13 and 14, totaling 5 armature teeth). In this way, the next coil is wound by ignoring the armature tooth at the center of the coil and with a spacing of 5 armature teeth, and in the opposite winding direction of the two adjacent coils of the same phase physical winding, until the winding is completed, and the tail end is U2. When current flows from the positive terminal A+ of U1 to the negative terminal A- of U2, magnetic fields US and UN are generated.

[0036] from Figure 2 It can be seen that the physical winding of phase V starts from V1, passes through the armature slot between armature teeth 4 and 5, and is wound clockwise to the armature slot between armature teeth 9 and 10, and then to the armature slot between armature teeth 15 and 16, and is wound counterclockwise to the armature slot between armature teeth 10 and 11 (excluding the armature teeth 7 and 13 at the center of the coil, there are a total of 5 armature teeth between the centers of these two adjacent coils, namely armature teeth 8, 9, 10, 11 and 12), and then to the middle of armature teeth 16 and 17. The winding is carried out clockwise from the armature slot at the center of the coil to the armature slot between teeth 21 and 22 (excluding teeth 13 and 19 at the center of the coil, there are five teeth between the centers of these two adjacent coils: teeth 14, 15, 16, 17, and 18). This process is repeated, ignoring the armature tooth at the center of the coil and winding the next coil in the opposite direction of the two adjacent coils of the same phase until the winding is completed. The end is V2. The W phase is wound in the same way to form ends W1 and W2.

[0037] The first coil of the U-phase winding is wound around teeth 1 and 5, with its center on tooth 3. The first coil of the V-phase winding is wound around teeth 5 and 9, with its center on tooth 7. Ignoring teeth 3 and 7, the centers of the two-phase windings are separated by teeth 4, 5, and 6. The same relationship exists between the V-phase and W-phase windings.

[0038] Figure 7 yes Figure 3 The single-slot distributed winding only shows the winding method of the U phase. Figure 7It can be seen that the U-phase physical winding starts from U1, passes through the armature slot between the armature teeth 1 and 24 to the armature slot between the armature teeth 3 and 4, and is wound clockwise. Then it goes to the armature slot between the armature teeth 6 and 7 to the armature slot between the armature teeth 3 and 4, and is wound counterclockwise (when the armature teeth 2 and 5 in the center of the coil are ignored, the centers of these two adjacent coils are separated by armature teeth 3 and 4, totaling 2 armature teeth). Then it goes to the armature slot between the armature teeth 6 and 7 to the armature slot between the armature teeth 9 and 10, and is wound clockwise (when the armature teeth 5 and 8 in the center of the coil are ignored, the centers of these two adjacent coils are separated by armature teeth 6 and 7, totaling 2 armature teeth). In this way, the next coil is wound by ignoring the armature tooth in the center of the coil and with a spacing of 2 armature teeth, and in the opposite winding direction of the two adjacent coils of the same phase physical winding, until the winding is completed, and the tail end is U2. When current flows from the positive terminal A+ of U1 to the negative terminal A- of U2, magnetic fields S and N are generated as shown in the figure.

[0039] Depend on Figure 3 As can be seen, the V-phase physical winding starts at V1, passes through the armature slot between teeth 2 and 3, and is wound clockwise to the slot between teeth 5 and 6. Then, it passes through the slot between teeth 8 and 9 and the slot between teeth 5 and 6, and is wound counterclockwise (ignoring teeth 4 and 7 at the center of the coil, the gap between these two adjacent coils is two teeth, 5 and 6). Then, it passes through the slot between teeth 8 and 9 and the slot between teeth 11 and 12, and is wound clockwise (ignoring teeth 7 and 10 at the center of the coil, the gap between these two adjacent coils is two teeth, 8 and 9). This continues, ignoring the center of the coil and winding in the opposite direction of the adjacent coils of the same phase, until the next coil is wound, ending at V2. The W-phase is wound in the same way, forming ends W1 and W2.

[0040] The first coil of the U-phase winding is wound around teeth 1 and 3, with its center on tooth 2. The first coil of the V-phase winding is wound around teeth 3 and 5, with its center on tooth 4. If teeth 2 and 4, where the center is located, are ignored, the center of the two-phase winding is separated by tooth 3. The same relationship applies to the V-phase and W-phase.

[0041] The two ends of each phase winding of the stator are connected to their own H-bridge power driver devices, see Figure 34T1 and T2 form the left arm of the first H-bridge U-phase, with the midpoint connected to U1; T3 and T4 form the right arm of the first H-bridge U-phase, with the midpoint connected to U2; T5 and T6 form the left arm of the second H-bridge V-phase, with the midpoint connected to V1; T7 and T8 form the right arm of the second H-bridge V-phase, with the midpoint connected to V2; T9 and T10 form the left arm of the third H-bridge W-phase, with the midpoint connected to W1; T11 and T12 form the right arm of the third H-bridge W-phase, with the midpoint connected to W2; they are controlled on and off by 12 input signals respectively, and each H-bridge group is controlled by four different control signals.

[0042] The above describes the structure of the single-slot distributed winding and the double-slot distributed winding of the invention. The following describes the driving mechanism of the motor and driver of the present invention in various driving states and the operation in the phase loss state.

[0043] Figures 9 to 32 The arrows on the outer wire ends of the stator above represent the direction of current flow in each driving state. US, UN, VS, VN, WS and WN in the figure represent the magnetism generated by the U-phase winding, V-phase winding and W-phase winding on the armature tooth at this time.

[0044] Drive circuit reference Figure 33 and Figure 34 , Figure 33 SW1 is the forward / reverse switch and SW2 is the run / stop switch. IC4 generates a circuit voltage +15V higher than the operating voltage V. Figure 34 IGBT used in Figure 33 IC1 is the MCU. Its built-in program makes the three Hall sensors HA, HB and HC give the corresponding drive as shown below when they are in different states. V1 is the speed control. Changing it makes the MCU give the pulse width modulation signal PWM wave with different duty cycle to adjust the motor speed. Figure 34 It can be seen that the power driver device of each phase winding is composed of an H-bridge power driver consisting of a left arm composed of two groups of composite fully controlled voltage-driven power semiconductor devices IGBTs connected in series, and a right arm composed of another two groups of composite fully controlled voltage-driven power semiconductor devices IGBTs connected in series. The starting and ending ends of each phase winding are connected to the midpoint of the left and right arms of their respective H-bridge power drivers. The upper and lower control terminals of the left and right arms of each group of H-bridge power drivers are respectively controlled by four different signals. The power driver device can also use high-power MOS field-effect transistors and other high-power semiconductor power devices.

[0045] The following is a combination of each driving state Figures 9 to 20 and Figure 33 , Figure 34 Describe:

[0046] When driving state 1, if Figure 9 Figure 10 As shown in the figure, the output states of the three Hall sensors are HA=L, HB=H and HC=H; there is no current flowing through the U phase, so it is hidden in the figure. Figure 33 SH3=L,SH5=L,SL3 and SL5 output PWM wave. Figure 34 In the middle, T7, T6, T9, and T12 are turned on, and the current flows in from W1 and V2, and flows out from W2 and V1. Figure 9 Figure 10 The magnetic poles and strengths shown, Figure 9 The south pole of the stator is synthesized on armature teeth 12 and 24, and the north pole is synthesized on armature teeth 18 and 6, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise: Figure 10 The south pole of the stator is synthesized between armature teeth 6 and 7 and between armature teeth 12 and 1, and the north pole is synthesized between armature teeth 9 and 10 and between armature teeth 3 and 4, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0047] In driving state 2, if Figure 11 and Figure 12 As shown in the figure, the output states of the three Hall sensors are HA=L, HB=L and HC=H; there is no current flowing through the W phase, so it is hidden in the figure. Figure 33 SH1=L,SH5=L,SL1 and SL5 output PWM wave to make Figure 34 In the middle, T7, T6, T1, and T4 are turned on, and the current flows in from U1 and V2, and flows out from U2 and V1. Figure 11 Figure 12 The magnetic poles and strengths shown, Figure 11 The south pole of the stator is synthesized on armature tooth 14 and armature tooth 2, and the north pole is synthesized on armature tooth 20 and armature tooth 8, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 12 The south pole of the stator is synthesized between armature teeth 7 and 8 and between armature teeth 1 and 2, and the north pole is synthesized between armature teeth 10 and 11 and between armature teeth 4 and 5, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0048] In driving state 3, if Figure 13 and Figure 14 As shown in the figure, the output states of the three Hall sensors are HA=H, HB=L and HC=H; there is no current flowing through the V phase, so it is hidden in the figure. Figure 33 SH1=L,SH6=L,SL1 and SL6 output PWM wave to make Figure 34 In the middle, T1, T4, T11, and T10 are turned on, and the current flows into U1 and W2, and flows out of U2 and W1. Figure 13 Figure 14The magnetic poles and strengths shown, Figure 13 The south pole of the stator is synthesized on armature tooth 16 and armature tooth 4, and the north pole is synthesized on armature tooth 22 and armature tooth 10, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 14 The south pole of the stator is synthesized between armature teeth 8 and 9 and between armature teeth 2 and 3, and the north pole is synthesized between armature teeth 11 and 12 and between armature teeth 5 and 6, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0049] When driving state 4, such as Figure 15 and Figure 16 As shown in the figure, the output states of the three Hall sensors are HA=H, HB=L and HC=L; there is no current flowing through the U phase, so it is hidden in the figure. Figure 33 SH2=L,SH6=L,SL2 and SL6 output PWM wave to make Figure 34 In the middle, T5, T8, T11, and T10 are turned on, and the current flows in from V1 and W2, and flows out from V2 and W1. Figure 15 Figure 16 The magnetic poles and strengths shown, Figure 15 The south pole of the middle stator is synthesized on armature tooth 18 and armature tooth 6, and the north pole is synthesized on armature tooth 24 and armature tooth 12, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 16 The south pole of the stator is synthesized between armature teeth 9 and 10 and between armature teeth 3 and 4, and the north pole is synthesized between armature teeth 12 and 1 and between armature teeth 6 and 7, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0050] When driving state 5, if Figure 17 and Figure 18 As shown in the figure, the output states of the three Hall sensors are HA=H, HB=H and HC=L; there is no current flowing through the W phase, so it is hidden in the figure. Figure 33 SH2=L,SH4=L,SL2 and SL4 output PWM wave to make Figure 34 In the middle, T5, T8, T3, and T2 are turned on, and the current flows in from V1 and U2, and flows out from V2 and U1. Figure 17 Figure 18 The magnetic poles and strengths shown, Figure 17 The south pole of the stator is synthesized on armature tooth 20 and armature tooth 8, and the north pole is synthesized on armature tooth 2 and armature tooth 14, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 18 The south pole of the stator is synthesized between armature teeth 10 and 11 and between armature teeth 4 and 5, and the north pole is synthesized between armature teeth 1 and 2 and between armature teeth 7 and 8, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0051] When driving state 6, if Figure 19 and Figure 20 As shown in the figure, the output states of the three Hall sensors are HA=L, HB=H and HC=L; there is no current flowing through the V phase, so it is hidden in the figure. Figure 33 SH3=L, SH4=L, SL3 and SL4 output PWM wave to make Figure 34 In the middle, T9, T12, T3, and T2 are turned on, and the current flows into W1 and U2, and flows out of W2 and U1. Figure 19 Figure 20 The magnetic poles and strengths shown, Figure 19 The south pole of the stator is synthesized on armature tooth 22 and armature tooth 10, and the north pole is synthesized on armature tooth 4 and armature tooth 16, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 20 The south pole of the stator is synthesized between armature teeth 11 and 12 and between armature teeth 5 and 6, and the north pole is synthesized between armature teeth 2 and 3 and between armature teeth 8 and 9, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0052] After driving state 6, the south pole of S2 on the rotor reaches Figure 2 The upper S1 is in the south pole position, and the process from drive state 1 to drive state 6 is repeated to form continuous operation of the motor rotor.

[0053] The above describes the operating state of the motor during normal driving. Figures 21 to 32 and Figure 33 , Figure 34 Description: Explain the operating state when one phase of the motor stator is missing. We take the U phase as an example. Due to the symmetry of the three-phase stator winding, the missing V phase and W phase are the same. The same conclusion is also obtained in our test. The U phase and its drive are removed below.

[0054] When driving state 1, if Figure 21 Figure 22 As shown, the output states of the three Hall sensors are HA=L, HB=H and HC=H; Figure 33 SH3=L,SH5=L,SL3 and SL5 output PWM wave. Figure 34 In the middle, T7, T6, T9, and T12 are turned on, and the current flows in from W1 and V2, and flows out from W2 and V1. Figure 21 Figure 22 The magnetic poles and strengths shown, Figure 21 The south pole of the stator is synthesized on armature teeth 12 and 24, and the north pole is synthesized on armature teeth 18 and 6, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 22The south pole of the stator is synthesized between armature teeth 6 and 7 and between armature teeth 12 and 1, and the north pole is synthesized between armature teeth 9 and 10 and between armature teeth 3 and 4, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0055] In driving state 2, if Figure 23 and Figure 24 As shown in the figure, the output states of the three Hall sensors are HA=L, HB=L and HC=H; there is no current flowing through the W phase, so it is hidden in the figure. Figure 33 SH5=L, SL5 outputs PWM wave to make Figure 34 In the middle, T7 and T6 are turned on, current flows into V2 and out of V1. Figure 23 Figure 24 The magnetic poles and strengths shown, Figure 23 The south pole of the stator is synthesized on armature tooth 13 and armature tooth 1, and the north pole is synthesized on armature tooth 19 and armature tooth 7, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 24 The south pole of the stator is synthesized on armature tooth 7 and armature tooth 1, and the north pole is synthesized on armature tooth 10 and armature tooth 4, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0056] In driving state 3, if Figure 25 and Figure 26 As shown in the figure, the output states of the three Hall sensors are HA=H, HB=L and HC=H; there is no current flowing through the V phase, so it is hidden in the figure. Figure 33 SH6=L, SL6 outputs PWM wave to make Figure 34 In the middle, T11 and T10 are turned on, current flows into W2 and out of W1. Figure 25 Figure 26 The magnetic poles and strengths shown, Figure 25 The south pole of the stator is synthesized on armature tooth 17 and armature tooth 5, and the north pole is synthesized on armature tooth 23 and armature tooth 11, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 26 The south pole of the stator is synthesized on armature teeth 9 and armature teeth 3, and the north pole is synthesized on armature teeth 12 and armature teeth 6, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0057] When driving state 4, such as Figure 27 and Figure 28 As shown, the output states of the three Hall sensors are HA=H, HB=L and HC=L; Figure 33 SH2=L,SH6=L,and SL2 and SL6 output PWM wave to make Figure 34 In the middle, T5, T8, T11, and T10 are turned on, and the current flows in from V1 and W2, and flows out from V2 and W1. Figure 27 Figure 28 The magnetic poles and strengths shown, Figure 27 The south pole of the stator is synthesized on armature tooth 18 and armature tooth 6, and the north pole is synthesized on armature tooth 24 and armature tooth 12, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 28 The south pole of the stator is synthesized between armature teeth 9 and 10 and between armature teeth 3 and 4, and the north pole is synthesized between armature teeth 12 and 1 and between armature teeth 6 and 7, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0058] When driving state 5, if Figure 29 and Figure 30 As shown in the figure, the output states of the three Hall sensors are HA=H, HB=H and HC=L; there is no current flowing through the W phase, so it is hidden in the figure. Figure 33 SH2=L, SL2 outputs PWM wave to make Figure 34 In the middle, T5 and T8 are turned on, current flows into V1 and out of V2. Figure 29 Figure 30 The magnetic poles and strengths shown, Figure 29 The south pole of the stator is synthesized on armature tooth 19 and armature tooth 7, and the north pole is synthesized on armature tooth 1 and armature tooth 13, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 30 The south pole of the stator is synthesized on armature tooth 10 and armature tooth 4, and the north pole is synthesized on armature tooth 1 and armature tooth 7, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0059] When driving state 6, if Figure 31 and Figure 32 As shown in the figure, the output states of the three Hall sensors are HA=L, HB=H and HC=L; there is no current flowing through the V phase, so it is hidden in the figure. Figure 33 SH3=L, SL3 outputs PWM wave to make Figure 34 In the middle, T9 and T12 are turned on, current flows into W1 and out of W2. Figure 31 Figure 32 The magnetic poles and strengths shown, Figure 31 The south pole of the stator is synthesized on armature tooth 23 and armature tooth 11, and the north pole is synthesized on armature tooth 5 and armature tooth 17, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise; Figure 32 The south pole of the stator is synthesized on armature teeth 12 and armature teeth 6, and the north pole is synthesized on armature teeth 3 and armature teeth 9, pushing and attracting the magnetic poles on the rotor to make the rotor rotate counterclockwise.

[0060] After driving state 6, the south pole of S2 on the rotor reaches Figure 2Upper S1 is in the south pole position, and the process from drive state 1 to drive state 6 is repeated to form the continuous operation of the motor rotor. It can be seen that the motor can also fully operate in the phase loss state. And it can restart normally in the phase loss state, that is, the phase loss will reduce the output power, but it will not damage the motor. When the broken phase winding is connected, the motor recovers its original performance. This is the same conclusion as the high-reliability radial magnetic field permanent magnet brushless motor we developed earlier, but due to the different physical structure and magnetic field mode, it is completely different from the patent perspective. At the same time, it can be seen that the high-reliability axial magnetic field permanent magnet brushless motor of the present invention is not only a study of the motor but also a study and reconstruction of its driver. Only the combination of the two can realize the functional characteristics of the present invention.

[0061] The present invention provides a high-reliability axial magnetic field permanent magnet brushless motor, which together constitute the present invention.

[0062] It will be apparent to those skilled in the art that the present invention encompasses, but is not limited to, the details of the exemplary embodiments described above, and that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations that come within the meaning and scope of equivalents of the claims are intended to be encompassed within the present invention. Any reference numerals in the claims should not be construed as limiting the claims to which they relate. It should be noted that magnetic position sensors come in a variety of forms, all of which function to accurately signal the rotor magnetic poles and do not alter the drive method of the motor phase windings. Similarly, microcontrollers (MCUs) come in a variety of models and can be constructed using components such as FPGAs (Field Programmable Gate Arrays), but these components are not the core of this patent. Generally speaking, for ease of production, the three-phase windings are wound in the same manner. Using different winding methods for some phase windings to achieve the same rotational result by simply changing the direction of the current drive is also encompassed by the present invention. Changing the starting slot position of the winding to adjust the current drive direction is also encompassed by the present invention.

Claims

1. High reliability axial magnetic field permanent magnet brushless motor, consisting of a motor and its driver circuit, is characterized by: The high-reliability axial magnetic field permanent magnet brushless motor has a stator plane perpendicular to the motor shaft. The stator, made of magnetic conductive material, is radially structured with armature teeth for winding the stator coils. The plane formed by the armature teeth is perpendicular to the motor shaft. Between the armature teeth on the stator are armature slots for winding three-phase physical windings. When powered, an axial magnetic field is generated. The mounting plane of the permanent magnets on the rotor is also perpendicular to the motor shaft. Its magnetic lines of force are distributed axially along the motor shaft. The north and south poles of the permanent magnets are arranged adjacent to each other, generating an axial magnetic field. The stator coils are wound in a distributed manner with a certain number of armature tooth slots separated. The adjacent coils of the same phase winding are wound in opposite directions, and the windings of each phase are placed a certain distance apart. Its driver circuit uses three groups of H-bridge power drivers, and the two ends of each phase winding on the stator are respectively connected to their own H-bridge power drivers.

2. The high-reliability axial magnetic field permanent magnet brushless motor according to claim 1 is characterized in that the relationship between the number of magnetic poles on the permanent magnet rotor of the high-reliability axial magnetic field permanent magnet brushless motor, the number of phases of the stator winding, and the number of armature slots on the stator per side is: the number of armature slots on the stator per side is equal to the sum of the number of south poles and north poles of the permanent magnets on the rotor per side multiplied by the number of phases of the stator winding 3 and then multiplied by the slot number K. When the slot number K is equal to 1, it is a single-slot structure, and when the slot number K is equal to 2, it is a double-slot structure.

3. The high-reliability axial magnetic field permanent magnet brushless motor according to claim 1 or claim 2, wherein the motor is characterized in that: in a single-slot structure with a slot multiplication number K equal to 1, when the number of armature slots on a single side of the stator is equal to the sum of the number of north and south magnetic poles on a single side of the permanent magnet rotor multiplied by the number of phases, two adjacent coils of the same phase winding of the stator are wound in opposite directions, and when the armature teeth on which the centers of the two adjacent coils are located are ignored, the centers of the two adjacent coils are separated by two armature teeth; when the armature teeth on which the centers of the coils of the two adjacent phase windings are ignored, the centers of the coils of the two adjacent phase windings are separated by one armature tooth, and the starting end and the ending end of each phase winding are respectively connected to their own H-bridge power drivers on the driver circuit.

4. The high-reliability axial magnetic field permanent magnet brushless motor according to claim 1 or claim 2, wherein the motor is characterized in that: in a double-slot structure with a slot multiplier K equal to 2, the number of armature slots on a single side of the stator of the high-reliability axial magnetic field permanent magnet brushless motor is equal to twice the number of phases multiplied by the sum of the north and south magnetic poles on a single side of the permanent magnet rotor; two adjacent coils of the same phase winding of the stator are wound in opposite directions; when the armature teeth at which the centers of the two adjacent coils are located are ignored, the centers of the two adjacent coils are separated by 5 armature teeth; when the armature teeth at which the centers of the coils of the two adjacent phase windings are ignored, the centers of the coils of the two adjacent phase windings are separated by 3 armature teeth; and the starting end and the ending end of each phase winding are respectively connected to their respective H-bridge power drivers on the driver circuit.

5. The high-reliability axial magnetic field permanent magnet brushless motor according to claim 1 or claim 2, wherein the motor is characterized in that: the mounting plane of the permanent magnets on the rotor of the high-reliability axial magnetic field permanent magnet brushless motor is perpendicular to the motor shaft, the magnetic lines of force of the mounted permanent magnets are distributed along the axial direction of the motor shaft, and the south pole and north pole of the permanent magnets are arranged adjacent to each other.

6. The high-reliability axial magnetic field permanent magnet brushless motor according to claim 1, wherein the driver circuit is characterized in that: the power driver device of each phase winding comprises an H-bridge power driver consisting of a left arm composed of two groups of composite fully-controlled voltage-driven power semiconductor devices (IGBTs) connected in series, and a right arm composed of another two groups of composite fully-controlled voltage-driven power semiconductor devices (IGBTs) connected in series, the starting end and the ending end of each phase winding are respectively connected to the midpoint of the left and right arms of the respective H-bridge power drivers, the upper and lower control terminals of the left and right arms of each group of H-bridge power drivers are respectively controlled by four different signals, and the power driver devices can also be high-power MOS field-effect transistors and other high-power semiconductor power devices.

7. The high-reliability radial magnetic field permanent magnet brushless motor according to claim 1, wherein the driver circuit thereof is characterized in that the rotation speed of the motor rotor is regulated by a pulse width modulation signal.

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