A Dynamic Phase Permanent Magnet Brushless DC Motor and Its Drive Control Method

Abstract

The present invention relates to a dynamic-phase permanent magnet brushless DC motor and its drive control method. The characteristics are as follows: the rotor of the motor is composed of an even number of arc-shaped permanent magnets with different magnetic polarities butt-jointed, and the stator is composed of an even number of tooth poles. Two tooth poles on a diameter line form an excitation pole pair. The single-chip microcomputer controls the switch drive circuit in real time according to the position of the rotating rotor, combines the stator excitation pole pairs into a current-maintaining pole pair unit and a current-commutating pole pair unit, and provides forward or reverse current to these two types of units in real time. In the present invention, the number of excitation pole pairs of the two types of units can be changed, and the coordinate positions of the magnetic polarities of the tooth poles of the two types of units are also changed, thereby forming a rotating magnetic field. The motor of the present invention eliminates negative torque, has continuous torque and small pulsation, is highly reliable and fault-tolerant, can meet the requirements of matching with the technical parameters of the operating equipment, and can also realize intelligent closed-loop automatic adjustment of the motor to meet the operating requirements of the equipment for speed, torque, etc.

Description

Technical Field

[0001] The present invention relates to a permanent magnet direct current brushless motor, and particularly to a dynamic phase permanent magnet direct current brushless motor and its drive control method. Background Art

[0002] The motor is the most effective power equipment for converting electrical energy into mechanical energy. It covers and penetrates into various industries and has now become the basic equipment for industrial modernization. In our country, due to the low application and popularization level of advanced motors, the efficiency is generally low. Among all power-consuming equipment, the power consumption of motors is particularly prominent. Currently, only motors consume about 70% of the total annual power generation in the country. It can be seen that it is important and urgent to improve the performance of motors. In the nearly 200-year development history of motors, various types of traditional motors have their own advantages and disadvantages. The matching degree of these motors with various different equipment is not ideal, and the comprehensive performance and versatility of motors are not high. Moreover, as the world enters the era of intelligent high-speed development, many new types of equipment put forward many newer and higher requirements for the matching power and control technologies.

[0003] The permanent magnet direct current brushless motor is a newly developed type of motor. It has been widely used in various industries due to its unique advantages such as energy conservation and high efficiency. The stator winding of the permanent magnet direct current brushless motor is structured based on phases, which can be two-phase, three-phase, four-phase, five-phase, or even twelve-phase, etc. The operation control of the motor is also to conduct and turn off in a strict logical sequence, commutate and reverse the windings of each phase at each stator coordinate position, so as to form a rotating magnetic field in the air gap of the motor and drive the rotor to rotate. However, during the commutation process, there are torque missing angles and negative torque conditions in the air gap between the rotor and the stator, which will affect the torque ripple and efficiency improvement of the motor. Therefore, in order to increase the torque of the motor and reduce the pulsation, more efforts are made to improve the motor control circuit, such as adopting vector control technology with complex operations, etc.

[0004] The object of the present invention is to provide a dynamic phase permanent magnet direct current brushless motor with a simple drive control device, an editable combination of the excitation poles of the motor with respect to the windings, and a variable coordinate position of the magnetic polarity of the excitation poles with respect to the tooth poles.

[0005] Another object of the present invention is to provide a drive control method for a dynamic phase permanent magnet direct current brushless motor. This method changes the fixed phase structure of the stator winding of the traditional permanent magnet direct current brushless motor into a dynamic phase structure, thereby generating a rotating magnetic field and making the rotor rotate synchronously.

[0006] To achieve the above object, the technical solution of the present invention is a dynamic-phase permanent magnet DC brushless motor, which comprises a motor body and a drive control device. It is characterized in that: the rotor of the motor body is composed of an even number of arc-shaped permanent magnets. Among the even number of arc-shaped permanent magnets, the inner arc surfaces of half of the arc-shaped permanent magnets are N poles and the outer arc surfaces are S poles, and the inner arc surfaces of the other half of the arc-shaped permanent magnets are S poles and the outer arc surfaces are N poles. The permanent magnets with N-pole inner arc surfaces are butt-jointed with the permanent magnets with S-pole inner arc surfaces to form a circular ring and are fixed on the magnetic conductor rotor frame; the stator of the motor body is composed of a stator base, tooth poles, excitation windings and a position sensor. An even number of tooth poles are evenly distributed in a circular shape on the stator base. Tooth slots are provided between the tooth poles. The central angles between the center lines of adjacent tooth poles are the same. Two tooth poles with a central angle of 180° are wound with the same excitation winding to form an excitation pole pair. The drive control device includes a stator excitation pole pair winding connection port, a switch drive circuit, a single-chip microcomputer and a power supply. The stator excitation pole pair winding connection port is electrically connected to both the switch drive circuit and the stator excitation pole pair winding. The single-chip microcomputer is electrically connected to both the switch drive circuit and the position sensor. The single-chip microcomputer receives the rotor rotation angle signal given by the position sensor and, through the switch drive circuit, edits and combines the stator excitation pole pair windings into two types of excitation pole pair units, one is a current-maintaining excitation pole pair unit and the other is a current-commutating excitation pole pair unit. At the same time, the single-chip microcomputer also controls the switch drive circuit to continuously provide a forward drive current to the current-maintaining excitation pole pair unit in real time, and provide a reverse drive current to the current-commutating excitation pole pair unit. Every time the single-chip microcomputer receives a signal from the position sensor, it immediately re-edits and combines the stator excitation pole pair windings through the drive switch circuit, and continuously provides a forward drive current to the newly combined current-maintaining excitation pole pair unit and a reverse drive current to the newly combined current-commutating excitation pole pair unit.

[0007] In the above technical solution of the dynamic-phase permanent magnet DC brushless motor, the number of stator tooth poles and tooth slots is both twenty-four. The central angle between the radial center lines of adjacent tooth poles is 15°. An excitation winding is arranged in the tooth slots of two tooth poles whose radial center line central angles are 180° to each other, that is, twelve excitation pole pairs are formed; the outer rotor of the motor body is composed of two arc-shaped permanent magnets, or four arc-shaped permanent magnets, or six arc-shaped permanent magnets, or eight arc-shaped permanent magnets and a cylindrical magnetic conductor rotor frame. The arc-shaped permanent magnets are butt-jointed with each other to form a cylindrical shape and are fixed on the inner surface of the cylindrical magnetic conductor rotor frame. The magnetic polarities of adjacent permanent magnets in the cylindrical permanent magnet are different, that is, the arc-shaped permanent magnet with an N-pole inner arc surface and an S-pole outer arc surface is butt-jointed with the arc-shaped permanent magnet with an S-pole inner arc surface and an N-pole outer arc surface.

[0008] In the above technical solution of the dynamic-phase permanent magnet brushless DC motor, the position sensor is a plurality of Hall position sensors. The Hall position sensors are installed on the stator base, and the Hall position sensors are arranged near the butt joint of two rotor permanent magnets with different magnetic polarities.

[0009] In the above technical solution of the dynamic-phase permanent magnet brushless DC motor, the position sensor is an encoder. The encoder is arranged on a shaft that rotates synchronously with the output shaft of the motor rotor, and outputs coordinate angle position pulse signals of each permanent magnet pole pair on the rotor.

[0010] In the above technical solution of the dynamic phase permanent magnet DC brushless motor, the drive control device further includes a display operation device, and the display operation control device includes a display screen and an operation panel. The power supply includes a control power supply and a drive power supply. The switch drive circuit is composed of a number of H-bridge DC solid state drive relays. The H-bridge DC solid state drive relays are electrically connected to the lead-out terminals of each excitation pole pair winding of the motor body stator through the lead-out terminals of the excitation pole pair windings. Each excitation pole pair winding of the motor body stator is connected to an H-bridge DC solid state drive relay. The single-chip microcomputer is divided into an excitation pole pair logic editing single-chip microcomputer and a logic operation control single-chip microcomputer. There are two control signal lines between the excitation pole pair ratio logic editing single-chip microcomputer and each H-bridge DC solid state drive relay circuit. One is the control positive current signal line and the other is the control negative current signal line. The excitation pole pair ratio logic editing single-chip microcomputer is also electrically connected to the display operation control device and the logic operation single-chip microcomputer. The logic operation single-chip microcomputer is also electrically connected to the display operation control device. The control power supply provides low-voltage weak electricity for the single-chip microcomputer and the display operation device. The drive power supply provides drive electric energy for the excitation pole pair windings through the H-bridge DC solid state drive relays. The excitation pole pair ratio logic editing single-chip microcomputer, according to the manual editing combination instruction issued by the display control device, combines all the excitation pole pair windings of the stator into two types of excitation pole pair winding units. One type is the current-maintaining excitation pole pair winding unit, and the other type is the current-reversing excitation pole pair winding unit. The excitation pole pair ratio logic editing single-chip microcomputer also receives the pre-compiled operation program instruction issued by the logic operation control single-chip microcomputer, and continuously provides a positive drive current to the current-maintaining excitation pole pair winding unit and a negative drive current to the current-reversing excitation pole pair winding unit in real time through the H-bridge DC solid state drive relays. The timing of providing the negative drive current to the current-reversing excitation pole pair winding unit is associated with the rotor rotation angle. The position sensor sends the rotor rotation angle information to the logic operation control single-chip microcomputer, so as to realize the closed-loop control between the rotor rotation angle and the editing combination of the excitation pole pair windings and the provision of the drive current. Every time the position sensor sends a signal, the single-chip microcomputer re-edits and combines each excitation pole pair winding, and the coordinate positions of the teeth of the newly edited and combined current-maintaining excitation pole pair winding unit and current-reversing excitation pole pair winding unit will deflect.

[0011] To achieve another object of the invention, the present invention also provides a driving and controlling method for a dynamic-phase permanent magnet brushless DC motor, which is characterized in that: the dynamic-phase permanent magnet brushless DC motor comprises a motor body and a driving and controlling device. The rotor of the motor body is composed of an even number of arc-shaped permanent magnets. For half of the even number of arc-shaped permanent magnets, the inner arc surface is an N pole and the outer arc surface is an S pole; for the other half of the arc-shaped permanent magnets, the inner arc surface is an S pole and the outer arc surface is an N pole. The permanent magnets with the inner arc surface being an N pole are butted against the permanent magnets with the inner arc surface being an S pole to form a circular ring and are fixed on a magnetic conductor rotor frame. The stator of the motor body is composed of a stator base, an exciting winding and a position sensor. An even number of tooth poles are evenly distributed in a circular ring on the stator base. Tooth slots are arranged between the tooth poles. The central angle degrees between the center lines of adjacent tooth poles are the same. Two tooth poles with a central angle degree of 180° wind the same exciting winding to form an exciting pole pair. The driving and controlling device comprises a stator exciting pole pair winding connection port, a switch driving circuit, a single-chip microcomputer, a position sensor and a power supply. The stator exciting pole pair winding connection port is electrically connected to both the switch driving circuit and the stator exciting pole pair winding. The single-chip microcomputer is electrically connected to both the switch driving circuit and the position sensor. The single-chip microcomputer receives the rotor rotation angle signal given by the position sensor and, through the switch driving circuit, edits and combines the stator exciting pole pairs into two types of exciting pole pair units, one type being a current-maintaining exciting pole pair unit and the other type being a current-reversing exciting pole pair unit. At the same time, the single-chip microcomputer also controls the switch driving circuit to continuously provide a forward driving current to the current-maintaining exciting pole pair unit in real time and provide a reverse driving current to the current-reversing exciting pole pair unit. Each time the position sensor sends a signal, the single-chip microcomputer and the switch driving circuit re-edit and combine the stator exciting pole pairs, and the coordinate positions of the tooth poles of the newly edited and combined current-maintaining exciting pole pair unit and current-reversing exciting pole pair unit also change once.

[0012] When a forward current is simultaneously input into the current-maintaining exciting pole pair winding unit and the current-reversing exciting pole pair unit with the same central angle within the central angle range corresponding to each permanent magnet, the magnetic polarities presented by the tooth poles of the current-maintaining exciting pole pair winding unit and the current-reversing exciting pole pair unit are different from the magnetic polarities of the permanent magnets they face. The tooth poles of the current-maintaining exciting pole pair unit and the current-reversing exciting pole pair unit form the shortest closed magnetic circuit with the permanent magnets they face, the rotor permanent magnets and the stator tooth poles reach magnetic balance, and the relative positions between the rotor and the stator remain unchanged.

[0013] When the exciting pole pair unit closest to the butt joint of adjacent permanent magnets in the counterclockwise direction is set as the current commutation exciting pole pair unit, during the current commutation of this current commutation exciting pole pair unit, the magnetic polarity of the teeth and poles of this current commutation exciting pole pair unit will change. And for the current maintaining exciting pole pair units within the central angle range corresponding to the same permanent magnet, since the current direction remains unchanged, the magnetic polarity of their teeth and poles is different from that of the teeth and poles of the current commutation exciting pole pair unit closest to the rear end in the counterclockwise direction, and is the same as that of the teeth and poles of the current commutation exciting pole pair unit closest to the front end in the counterclockwise direction. At this moment, the coordinate positions of the teeth and poles with the same magnetic polarity are deflected counterclockwise compared to the coordinate positions of the teeth and poles with the same magnetic polarity in the previous magnetic balance state. The magnetic balance between the rotor permanent magnet and the stator teeth and poles is broken, and the magnetic force lines are distorted and elongated. Since the magnetic force lines follow the shortest closed loop law, it forces the rotor permanent magnet to rotate counterclockwise to achieve the magnetic balance between the rotor permanent magnet and the stator teeth and poles again;

[0014] Once the magnetic balance between the rotor permanent magnet and the stator teeth and poles is achieved again, the position sensor sends a signal to the single-chip microcomputer and the switch drive circuit. The single-chip microcomputer and the switch drive circuit re-edit and combine the stator exciting pole pairs again, and once again set the exciting pole pair unit closest to the butt joint of adjacent permanent magnets in the counterclockwise direction as the new current commutation exciting pole pair unit, and set the other exciting pole pairs within the central angle range corresponding to the same permanent magnet as the new current maintaining exciting pole pair units. After the current of this current commutation exciting pole pair unit is commutated, the above process is repeated. The coordinate positions of the teeth and poles with the same magnetic polarity are deflected counterclockwise again. The magnetic balance between the rotor permanent magnet and the stator teeth and poles is broken, and the magnetic force lines are distorted and elongated. Since the magnetic force lines follow the shortest closed loop law, it forces the rotor to rotate counterclockwise, and the magnetic balance between the rotor permanent magnet and the stator teeth and poles is achieved again;

[0015] By continuously repeating the above process, the teeth and poles of the stator exciting pole pairs form a rotating magnetic field in the counterclockwise direction, thereby driving the rotor permanent magnet to rotate synchronously counterclockwise;

[0016] Similarly, when the single-chip microcomputer and the switch drive circuit set the exciting pole pair unit closest to the butt joint of the permanent magnet in the clockwise direction as the current commutation exciting pole pair unit, and set the other exciting pole pairs within the central angle range corresponding to the same permanent magnet as the current maintaining exciting pole pair units, under this setting condition, the rotor rotates in the clockwise direction;

[0017] The number of exciting pole pairs combined by each current maintaining exciting pole pair unit and current commutation exciting pole pair unit facing each other within the central angle range corresponding to each permanent magnet of the rotor can be manually set and corrected, or can be preset by single-chip microcomputer programming, or can be automatically adjusted in real-time closed-loop by the single-chip microcomputer according to the operating state of the motor.

[0018] In the above-mentioned dynamic phase permanent magnet brushless DC motor drive control method, the method in which the single chip microcomputer makes real-time adjustments according to the running state of the motor is that, first, when the motor starts, the number of excitation pole pairs set by the excitation pole pair unit closest to the permanent magnet docking point is relatively small, that is, within the corresponding central angle range of the same permanent magnet, the ratio of the number of excitation pole pairs set by the current maintaining excitation pole pair unit to the number of excitation pole pairs set by the current commutation excitation pole pair unit is relatively large. After the motor starts, as the motor load changes or the speed increases, the single chip microcomputer gradually adjusts the excitation pole pairs set by the current commutation excitation pole pair commutation unit closest to the permanent magnet docking point. The number of magnetic pole pairs is optimized so that the ratio of the number of excitation pole pairs set by the current maintaining excitation pole pair unit to the number of excitation pole pairs set by the current commutation excitation pole pair unit is optimal, until the motor reaches the best matching state with the running equipment; secondly, according to the coordinate angular position of the current maintaining excitation pole pair unit and the current commutation excitation pole pair unit and the permanent magnets on the rotor, the magnitude of the positive and negative currents input to the current maintaining excitation pole pair unit and the current commutation excitation pole pair unit are closed or adjusted in real time to achieve the goal of minimizing the input current, saving energy and improving the working efficiency of the motor while meeting the conditions required for the operation of the motor equipment.

[0019] In order to meet the urgent needs of modern intelligent development for power sources, the present invention has gone beyond the traditional motor structure and control technology form, and has developed a motor that is compatible with and absorbs the advantages of traditional induction motors, DC motors, permanent magnet DC brushless motors and switched reluctance motors, while avoiding and making up for their respective defects and deficiencies as much as possible, so that the motor can have the unique performance of higher efficiency, energy saving, large torque output at low speed, high safety and reliability, and intelligent regulation, and can better meet the needs of new equipment for the development of new power in the development of science and technology.

[0020] The present invention breaks through the existing mode in motors where a "phase" is composed of a fixed number of exciting pole pairs, and the coordinate positions of the tooth poles of each "phase" exciting pole pair are also fixed and unchangeable. The present invention divides the stator exciting pole pairs into two types of exciting pole pair units. One type is the current-maintaining exciting pole pair unit, and the other type is the current-commutating exciting pole pair unit. This is similar to the "two poles" in the traditional sense. However, although the sum of the number of exciting pole pairs included in the two types of exciting pole pair units set by the present invention is a constant number, the ratio of the number of exciting pole pairs included in the two types of exciting pole pair units is changeable. And as the motor starts and runs, the two types of units will continuously consist of different exciting pole pairs, and the coordinate positions of the tooth poles of the exciting pole pairs included in the newly formed two types of exciting pole pair units will also change gradually. If using the concept of "phase" in the traditional sense to describe, both the number of exciting pole pairs combined in the "phase" of the present invention and the coordinate position of the "phase" tooth poles are dynamic. Through a single-chip microcomputer and a switch driving circuit, independent control is carried out on each stator exciting pole pair winding to achieve the splitting and recombination required to form a "dynamic phase", so as to generate a rotating magnetic field through the "dynamic phase" structure, enabling the motor to obtain large torque and small pulsation output.

[0021] The technical effects and advantages of the present invention are as follows:

[0022] (1) The present invention adopts a dynamic phase transitional commutation method. Only a part of the exciting pole pair windings for each current commutation is the entire exciting pole pair windings, and the other part still maintains the original current direction, thus reducing the impact of the commutation current.

[0023] (2) The commutation inductance of the present invention is reduced, the reverse voltage is decreased, and the commutation speed is increased.

[0024] (3) During the operation of the motor of the present invention, the current direction in the winding of the current-maintaining exciting pole pair unit is always maintained unchanged. The tooth poles of these current-maintaining exciting pole pair units maintain continuous torque with the rotor permanent magnet poles, which not only improves the torque output but also greatly reduces the torque pulsation.

[0025] (4) The present invention eliminates the negative torque in the air gap between the stator and the rotor, making the torque force in the air gap all in the same direction.

[0026] (5) Once a traditional motor is finalized, the parameters of each motor are fixed and unchangeable and cannot be corrected, which results in a low matching degree between the motor and the equipment. However, the present invention can control the splitting and recombination of each stator exciting pole pair winding through a logic editing control program to meet the technical parameter matching requirements of the operating equipment, and can also achieve the closed-loop automatic adjustment of an intelligent motor to meet the operating requirements of the equipment for speed, torque, etc.

[0027] (6) The present invention has high reliability and high fault tolerance. When a fault occurs in a certain field pole pair in the motor, the remaining field pole pairs can continue to operate normally, which has extremely high value for the safe use in high-risk areas with high reliability requirements.

[0028] (7) The present invention can achieve constant torque output. This motor with low-speed and high-torque output is particularly suitable for equipment that requires heavy-load starting and frequent speed changes, such as electric vehicles, high-speed rails, ships, etc.

[0029] (8) The present invention eliminates the strict logic control of phase sequence commutation. As long as the commutation control of each unit is carried out according to the position signal, the reliability is greatly improved. Description of the Drawings

[0030] Figure 1 It is the structure of the motor body and the magnetic polarity state diagram (magnetic balance) before starting in the first embodiment of the present invention.

[0031] Figure 2 It is the magnetic polarity state diagram when the field pole pair unit closest to the permanent magnet docking is turned off in the first embodiment of the present invention.

[0032] Figure 3 It is the magnetic polarity state diagram when the current of the field pole pair unit closest to the permanent magnet docking is reversed in the first embodiment of the present invention.

[0033] Figure 4 It is the magnetic polarity state diagram when the motor rotor rotates 60°, and the rotor permanent magnet and the stator field pole pair reach magnetic balance in the first embodiment of the present invention.

[0034] Figure 5 It is the magnetic polarity state diagram when the current of the field pole pair unit closest to the permanent magnet docking is turned off in the first embodiment of the present invention.

[0035] Figure 6 It is the magnetic polarity state diagram when the current of the field pole pair unit closest to the permanent magnet docking is reversed in the first embodiment of the present invention.

[0036] Figure 7 It is the magnetic polarity state diagram when the motor rotor rotates 120°, and the rotor permanent magnet and the stator field pole pair reach magnetic balance in the first embodiment of the present invention.

[0037] Figure 8 It is the magnetic polarity state diagram when the current of the field pole pair unit closest to the permanent magnet docking is turned off in the first embodiment of the present invention.

[0038] Figure 9 It is the magnetic polarity state diagram when the current of the field pole pair unit closest to the permanent magnet docking is reversed in the first embodiment of the present invention.

[0039] Figure 10It is the first embodiment of the present invention. The motor rotor rotates 180°, and the rotor permanent magnet and the stator excitation pole pair reach the magnetic balance magnetic polarity state diagram.

[0040] Figure 11 It is the first embodiment of the present invention. The magnetic polarity state diagram when the current of the excitation pole pair unit closest to the permanent magnet docking place is turned off.

[0041] Figure 12 It is the first embodiment of the present invention. The magnetic polarity state diagram when the current of the excitation pole pair unit closest to the permanent magnet docking place is reversed.

[0042] Figure 13 It is the first embodiment of the present invention. The motor rotor rotates 240°, and the rotor permanent magnet and the stator excitation pole pair reach the magnetic balance magnetic polarity state diagram.

[0043] Figure 14 It is the first embodiment of the present invention. The magnetic polarity state diagram when the current of the excitation pole pair unit closest to the permanent magnet docking place is turned off.

[0044] Figure 15 It is the first embodiment of the present invention. The magnetic polarity state diagram when the current of the excitation pole pair unit closest to the permanent magnet docking place is reversed.

[0045] Figure 16 It is the first embodiment of the present invention. The motor rotor rotates 300°, and the rotor permanent magnet and the stator excitation pole pair reach the magnetic balance magnetic polarity state diagram.

[0046] Figure 17 It is the first embodiment of the present invention. The magnetic polarity state diagram when the current of the excitation pole pair unit closest to the permanent magnet docking place is turned off.

[0047] Figure 18 It is the first embodiment of the present invention. The magnetic polarity state diagram when the current of the excitation pole pair unit closest to the permanent magnet docking place is reversed.

[0048] Figure 19 It is the first embodiment of the present invention. The motor rotor rotates 360°, and the rotor permanent magnet and the stator excitation pole pair reach the magnetic balance magnetic polarity state diagram.

[0049] Figure 20 It is the first embodiment of the present invention. The circuit principle block diagram of the motor drive control device.

[0050] Figure 21 It is the second embodiment of the present invention. The schematic diagram of the magnetic polarity state when the current maintains eleven excitation pole pairs in the excitation pole pair unit (A unit) and one excitation pole pair in the current commutation excitation pole pair unit (B unit), and the current of the B unit is turned off.

[0051] Figure 22This is the second embodiment of the present invention. It is a schematic diagram of the magnetic polarity state when the current of the current-maintaining excitation pole pair unit (Unit A) has ten excitation pole pairs and the current of the current-reversing excitation pole pair unit (Unit B) has two excitation pole pairs, and the current of Unit B is turned off.

[0052] Figure 23 This is the second embodiment of the present invention. It is a schematic diagram of the magnetic polarity state when the current of the current-maintaining excitation pole pair unit (Unit A) has nine excitation pole pairs and the current of the current-reversing excitation pole pair unit (Unit B) has three excitation pole pairs, and the current of Unit B is turned off.

[0053] Figure 24 This is the second embodiment of the present invention. It is a schematic diagram of the magnetic polarity state when the current of the current-maintaining excitation pole pair unit (Unit A) has eight excitation pole pairs and the current of the current-reversing excitation pole pair unit (Unit B) has four excitation pole pairs, and the current of Unit B is turned off.

[0054] Figure 25 This is the second embodiment of the present invention. It is a schematic diagram of the magnetic polarity state when the current of the current-maintaining excitation pole pair unit (Unit A) has seven excitation pole pairs and the current of the current-reversing excitation pole pair unit (Unit B) has five excitation pole pairs, and the current of Unit B is turned off.

[0055] Figure 26 This is the second embodiment of the present invention. It is a schematic diagram of the magnetic polarity state when the current of the current-maintaining excitation pole pair unit (Unit A) has six excitation pole pairs and the current of the current-reversing excitation pole pair unit (Unit B) has six excitation pole pairs, and the current of Unit B is turned off.

[0056] Figure 27 This is the second embodiment of the present invention. It is a schematic diagram of the magnetic polarity state when the current of the current-maintaining excitation pole pair unit (Unit A) has five excitation pole pairs and the current of the current-reversing excitation pole pair unit (Unit B) has seven excitation pole pairs, and the current of Unit B is turned off.

[0057] Figure 28 This is the second embodiment of the present invention. It is a schematic diagram of the magnetic polarity state when the current of the current-maintaining excitation pole pair unit (Unit A) has four excitation pole pairs and the current of the current-reversing excitation pole pair unit (Unit B) has eight excitation pole pairs, and the current of Unit B is turned off.

[0058] Figure 29 This is the second embodiment of the present invention. It is a schematic diagram of the magnetic polarity state when the current of the current-maintaining excitation pole pair unit (Unit A) has three excitation pole pairs and the current of the current-reversing excitation pole pair unit (Unit B) has nine excitation pole pairs, and the current of Unit B is turned off.

[0059] Figure 30 This is the second embodiment of the present invention. It is a schematic diagram of the magnetic polarity state when the current of the current-maintaining excitation pole pair unit (Unit A) has two excitation pole pairs and the current of the current-reversing excitation pole pair unit (Unit B) has ten excitation pole pairs, and the current of Unit B is turned off.

[0060] Figure 31It is Embodiment 2 of the present invention. The current-maintaining excitation pole pair unit (Unit A) has one excitation pole pair, and the current-reversing excitation pole pair unit (Unit B) has eleven excitation pole pairs. This is a schematic diagram of the magnetic polarity state when the current in Unit B is turned off.

[0061] Figure 32 It is Embodiment 3 of the present invention. The outer rotor of the motor body is composed of four permanent magnets butt-jointed, and the stator is composed of twenty-four teeth and twelve excitation pole pairs. This is a schematic diagram of the structure and the magnetic balance state diagram before the motor starts.

[0062] Figure 33 It is Embodiment 3 of the present invention. The current-maintaining excitation pole pair unit (Unit A) has four excitation pole pairs, and the current-reversing excitation pole pair unit (Unit B) has two excitation pole pairs. This is a schematic diagram of the magnetic polarity state when the current in Unit B is turned off.

[0063] Figure 34 It is Embodiment 3 of the present invention. This is a diagram of the magnetic polarity state when the current in the current-reversing excitation pole pair unit (Unit B) is reversed.

[0064] Figure 35 It is Embodiment 3 of the present invention. When the motor rotor rotates 30°, this is a diagram of the magnetic polarity state where the rotor permanent magnet and the stator excitation pole pair reach magnetic balance.

[0065] Figure 36 It is Embodiment 4 of the present invention. The outer rotor of the motor body is composed of six permanent magnets butt-jointed, and the stator is composed of twenty-four teeth and twelve excitation pole pairs. This is a schematic diagram of the structure and the magnetic balance state diagram before the motor starts.

[0066] Figure 37 It is Embodiment 4 of the present invention. The current-maintaining excitation pole pair unit (Unit A) has three excitation pole pairs, and the current-reversing excitation pole pair unit (Unit B) has one excitation pole pair. This is a schematic diagram of the magnetic polarity state when the current in Unit B is turned off.

[0067] In the above figures, 100 is the display control device, 101 is the rectifier circuit, 102 is the inverter circuit, 103 is the drive power supply, 104 is the control power supply, 105 is the logic operation control single-chip microcomputer, 106 is the single-chip microcomputer for editing and combining the excitation pole pairs into two types of units, 107 is one of the H-bridge DC solid-state drive relays, 108 is the second H-bridge DC solid-state drive relay, 109 is the eleventh H-bridge DC solid-state drive relay, 110 is the twelfth H-bridge DC solid-state drive relay, 111 is the wiring port of the stator excitation pole pair winding, 112 is the position sensor, 113 is the fault protection circuit, and 114 is the motor body. Detailed Embodiments

[0068] The following describes the specific embodiments of the present invention with reference to the accompanying drawings.

[0069] For a concise and accurate description of the embodiments of the present invention, the following briefly explains the terms and nouns involved in the embodiments of the present invention.

[0070] First, permanent magnet pole pair: It refers to an even number of annular permanent magnets connected end to end. Two permanent magnets that are relatively arranged, that is, two permanent magnets located on the same diameter line and relatively arranged, form a permanent magnet pole pair. The magnetic polarities of the two permanent magnets in the same permanent magnet pole pair can be different or the same.

[0071] Second, permanent magnet docking location: It refers to the seam where annular permanent magnets with different magnetic polarities are docked with each other, and it is also the part where the magnetic polarities of adjacent permanent magnets change.

[0072] Third, central angle corresponding to the permanent magnet: It refers to the angle between the radial rays drawn from the axis of rotation of the motor to both ends of the same arc-shaped permanent magnet. The rotor permanent magnets are annular. When the annular is composed of two permanent magnets, the central angle corresponding to each permanent magnet is 180°; when it is composed of four permanent magnets, the central angle corresponding to each permanent magnet is 90°; when it is composed of six permanent magnets, the central angle corresponding to each permanent magnet is 60°; when it is composed of eight permanent magnets, the central angle corresponding to each permanent magnet is 45°.

[0073] Fourth, exciting pole pair: The tooth poles wound by the same exciting winding form an exciting pole pair. The two tooth poles of the same exciting pole pair are located at both ends of the same diameter line, and the central angle between the two tooth poles of the same exciting pole pair is 180°. The magnetic polarities of the tooth poles of the same exciting pole pair change simultaneously with the change of the direction of the exciting current. The magnetic polarities of the two tooth poles of the same exciting pole pair can be different or the same.

[0074] Fifth, exciting pole pair unit: It refers to a combination of exciting pole pairs controlled by the same driving current. The exciting pole pair unit can be composed of different numbers of exciting pole pairs (not limited to one exciting pole pair). The exciting pole pair unit with the driving current direction remaining unchanged is the current-maintaining exciting pole pair unit, and the magnetic polarities of all the tooth poles of this unit remain unchanged. While the exciting pole pair unit with the driving current direction reversing is the current-reversing exciting pole pair unit, and the magnetic polarities of all the tooth poles of this unit will change due to the reversal of the driving current.

[0075] Sixth, exciting pole pair tooth pole coordinate position: The polar angle concept in polar coordinates is used to represent the specific positions of the exciting pole pair tooth poles evenly distributed on the stator base.

[0076] Seventh, magnetic balance: It means that the magnetic polarities of the rotor permanent magnet pole pairs are different from those of the stator exciting pole pair tooth poles, and the closed magnetic circuit is the shortest. Embodiment 1

[0077] The cross-sectional structure of the motor body in this embodiment is as shown in the appendix Figure 1As shown, the outer rotor is composed of two semi-circular permanent magnets butt-jointed. The joints of the two permanent magnets are located at the due north and due south positions (the 0 o'clock and 6 o'clock positions of the clock). The stator has twenty-four tooth poles, which are respectively marked as tooth pole 1 - tooth pole 24 , the central angle of the center lines of adjacent tooth poles is 15°, and the tooth poles with a central angle of 180° to each other wind an exciting winding to form twelve exciting pole pairs. Three Hall position sensors AX, BX, and CX are respectively set at 0°, 60°, and 120°.

[0078] The circuit principle block diagram of the motor drive control device in this embodiment is as shown in the appendix Figure 20 .

[0079] Appendix Figure 20 In it, the rectifier circuit 101 and the inverter circuit 102 convert alternating current into a drive current 103 and a control power supply 104. The drive power supply 103 provides a drive current for the exciting pole pair windings through twelve H-bridge DC solid-state drive relays. The control power supply 104 provides a working power supply for the display operation control device 100, the logic operation single-chip microcomputer 105, and the exciting pole pair editing combined into two types of unit single-chip microcomputers 106. The twelve pairs of control signal lines of the exciting pole pair editing combined into two types of unit single-chip microcomputers 106 are respectively electrically connected to the twelve H-bridge DC solid-state drive relays. In each pair of control signal lines, one signal line controls the presence or absence of a forward current, and the other signal line controls the presence or absence of a reverse current. The twelve H-bridge DC solid-state drive relays are respectively electrically connected to the twelve exciting pole pair windings of the stator of the motor body 114 through the stator exciting pole pair winding connection ports 111, that is, the H-bridge DC solid-state drive relay (1) is connected to the tooth pole 1 and the tooth pole 13 pole pair winding, the H-bridge DC solid-state drive relay (2) is connected to the tooth pole 2 and the tooth pole 14 pole pair winding, and so on. The H-bridge DC solid-state drive relay (11) is connected to the tooth pole 11 and the tooth pole 23 pole pair winding, and the H-bridge DC solid-state drive relay (12) is connected to the tooth pole 12 and the tooth pole 24 pole pair winding. The position sensor (signal sampling) 112 is arranged in the motor body 114. The position sensor 112 transmits the sampling signal to the logic operation single-chip microcomputer 105, and at the same time transmits the sampling signal to the fault protection circuit 113. The fault protection circuit 113 respectively transmits the circuit protection signal to the logic operation single-chip microcomputer 105 and the twelve H-bridge DC solid-state drive relays.

[0080] In this embodiment, the display control device 100 and the excitation pole pair are edited and combined into two types of unit single-chip microcomputers 106. The twelve excitation pole pairs of the stator are edited and combined into two types of excitation pole pair units. One type is the current-maintaining excitation pole pair unit, and the other type is the current-reversing excitation pole pair unit. It is determined that the current-maintaining excitation pole pair unit is composed of eight excitation pole pairs, and the current-reversing excitation pole pair unit is composed of four excitation pole pairs. As shown in the attached Figure 2 and the attached Figure 3 figure, the initial current-reversing excitation pole pair unit is composed of tooth pole 1 - tooth pole 4 and tooth pole 13 - tooth pole 16 combined. The initial current-maintaining excitation pole pair unit is composed of tooth pole 5 - tooth pole 8 and tooth pole 17 - tooth pole 20 , tooth pole 9 - tooth pole 12 and tooth pole 21 - tooth pole 24 combined.

[0081] Before the motor starts, the logic operation single-chip microcomputer 105 and the excitation pole pair are edited and combined into two types of unit single-chip microcomputers 106 to control the drive power supply 103 to input positive current (1+, 2+,... 11+, 12+) to all twelve H-bridge DC solid-state drive relays at the same time. At this moment, tooth poles 1 to tooth pole 12 all show as N poles, and tooth pole 13 to tooth pole 24 all show as S poles. Refer to the attached Figure 1 figure. At this moment, the magnetic force lines between the permanent magnet and the excitation pole pair are the shortest, and the rotor and the stator reach magnetic balance, and the relative positions of the rotor and the stator remain unchanged.

[0082] When the motor starts, the logic operation single-chip microcomputer 105 and the excitation pole pair are edited and combined into two types of unit single-chip microcomputers 106 to control the drive power supply 103 and the H-bridge DC solid-state drive relays (1) to H-bridge DC solid-state drive relays (4) to turn off the drive current of the current-reversing excitation pole pair unit (tooth poles 1 to tooth pole 4 and tooth pole 13 to tooth pole 16 excitation pole pair unit) closest to the permanent magnet docking points (0° position and 180° position). At the same time, the H-bridge DC solid-state drive relays (5) to H-bridge DC solid-state drive relays (12) continue to supply the drive current in the original direction to the current-maintaining excitation pole pair unit (tooth poles 5 to tooth pole 12 and tooth pole 17 to tooth pole 24 ). At this moment, the magnetic polarities of tooth poles 1 to tooth pole 4 and tooth pole 13 to tooth pole 16 disappear, and the magnetic polarities of tooth poles 5 to tooth pole 12 and tooth pole 17 to tooth pole 24The magnetic polarity remains unchanged, and the magnetic balance before motor startup is broken. See the appendix Figure 2 .

[0083] Instantaneously, the H-bridge DC solid-state drive relays (1) to (4) input reverse drive current to the current commutation excitation pole pair unit (pole teeth 1 to 4 and pole teeth 13 to pole teeth 16 ). The magnetic polarities of pole teeth 1 to 4 change to the S pole, and the magnetic polarities of pole teeth 13 to pole teeth 16 change to the N pole. See the appendix Figure 3 . At this moment, the magnetic polarities of pole teeth 5 to pole teeth 12 and pole teeth 13 to pole teeth 16 are all N poles, while the magnetic polarities of pole teeth 17 to pole teeth 24 and pole teeth 1 to 4 are all S poles. The permanent magnet on the inner arc surface of the outer rotor with the S pole is subjected to the magnetic attraction from the N poles of pole teeth 5 to pole teeth 12 and the N poles of pole teeth 13 to pole teeth 16 . At the same time, the permanent magnet on the inner arc surface of the outer rotor with the S pole is also subjected to the magnetic repulsion from the S-pole pole teeth 1 to 4. Relatively, the permanent magnet on the inner arc surface of the outer rotor with the N pole is subjected to the magnetic attraction from the S poles of pole teeth 17 to pole teeth 24 and pole teeth 1 to 4. At the same time, the permanent magnet on the inner arc surface of the outer rotor with the N pole is also subjected to the magnetic repulsion from the N-pole pole teeth 13 to pole teeth 16 . Comparing appendix Figure 1 with appendix Figure 2 , it can be seen that the coordinate position of the pole teeth with the N magnetic polarity has a deflection of a 60-degree central angle. At this moment, the magnetic torque formed by the stator pole teeth with the deflected magnetic polarity on the rotor permanent magnet causes the outer rotor permanent magnet to obtain a magnetic torque for counterclockwise rotation, forcing the rotor to rotate counterclockwise by a 60-degree step angle. After the outer rotor rotates counterclockwise by a 60° step angle, the magnetic force lines between the rotor permanent magnet and the stator excitation pole pair teeth are the shortest, and the rotor permanent magnet and the stator excitation teeth reach magnetic balance again. See the appendix Figure 4 . Once magnetic balance is achieved, the Hall position sensor BX captures the change in magnetic polarity at the permanent magnet docking location and sends a signal to the logic operation single-chip microcomputer 105. The excitation pole pair is edited and combined into two types of unit single-chip microcomputers 106, which then combine pole teeth 5 to 8 and pole teeth 17 to pole teeth 20 closest to the permanent magnet docking seam (60° and 240°) into a new current commutation excitation pole pair unit, and pole teeth 9 to pole teeth 16 and pole teeth 21 to pole teeth 24, the tooth poles 1 to 4 are combined into a new current-maintaining excitation pole pair unit. This time, the H-bridge DC solid-state drive relays (5) to (8) turn off the drive current of the current-commutating excitation pole pair unit (tooth poles 5 to 8 and tooth poles 17 to tooth poles 20 winding), see Appendix Figure 5 , the magnetic polarities of tooth poles 5 to 8 and tooth poles 17 to tooth poles 20 disappear. The H-bridge DC solid-state drive relays (1) to (4) and the H-bridge DC solid-state drive relays (9) to (12) continuously supply the drive current in the original direction to the current-maintaining excitation pole pair unit (tooth poles 9 to tooth poles 16 and tooth poles 21 to tooth poles 24 and tooth poles 1 to 4). The magnetic polarities of tooth poles 9 to tooth poles 16 and tooth poles 21 to tooth poles 24 and tooth poles 1 to 4 remain unchanged. Instantaneously, the H-bridge DC solid-state drive relays (5) to (8) input a reverse drive current to the current-commutating excitation pole pair unit (tooth poles 5 to 8 and tooth poles 17 to tooth poles 20 ). The magnetic polarity of tooth poles 5 to 8 is the S pole, and the magnetic polarity of tooth poles 17 to tooth poles 20 is the N pole, see Appendix Figure 6 . For the newly combined current-maintaining excitation pole pair unit group, the magnetic polarities of tooth poles 9 to tooth poles 16 and tooth poles 17 to tooth poles 20 are all the N pole, forming a magnetic attraction to the permanent magnet with the S pole on the inner arc surface of the outer rotor. At the same time, the permanent magnet with the S pole on the inner arc surface of the outer rotor is also magnetically repelled by the tooth poles 5 to 8 with the S pole magnetic polarity. In terms of relative position, the magnetic polarities of tooth poles 21 to tooth poles 24 and tooth poles 1 to 8 are the S pole, forming a magnetic attraction to the permanent magnet with the N pole on the inner arc surface, while the magnetic polarities of tooth poles 17 to tooth poles 20 are the N pole, forming a magnetic repulsion to the permanent magnet with the N pole on the inner arc surface. The outer rotor permanent magnet obtains a magnetic torque for counterclockwise rotation again, causing the outer rotor to continue rotating counterclockwise by a 60° step angle to reach another magnetic balance, see Appendix Figure 7 . At this moment, the Hall position sensor CX captures the change in the magnetic polarity at the docking position of the permanent magnet and sends a signal to the logic operation single-chip microcomputer 105 again, causing the excitation pole pair editing to be combined into two types of unit single-chip microcomputers 106 to recombine the new current-maintaining excitation pole pair unit and the current-commutating excitation pole pair unit, see Appendix Figure 8, and the drive current of the newly combined current commutation excitation pole pair unit is turned off by the H-bridge DC solid-state drive relays from (9) to (12). Immediately afterwards, the drive current is commutated, and the drive current is continuously input to the newly combined current maintenance excitation pole pair unit by the H-bridge DC solid-state drive relays from (1) to (8). See Appendix Figure 9 . Repeat the above steps to continue rotating the outer rotor counterclockwise by a step angle of 60°. See Appendix Figure 10 . Cycle in this way, and the outer rotor rotates counterclockwise by 360°. See Appendix Figure 11 to Appendix Figure 19 . The motor rotor rotates one week, completing a drive control cycle. The outer rotor permanent magnet rotates synchronously under the action of the stator tooth pole rotating magnetic field.

[0084] In this embodiment, during the two magnetic balance periods of the motor rotor permanent magnet and the stator excitation tooth poles, an editing combination of the current maintenance excitation pole pair unit and the current commutation excitation pole pair unit is completed, and the current commutation of the current commutation excitation pole pair unit is also completed. The rotor rotates by a central angle of sixty degrees. In short, this embodiment generates a rotating magnetic field through the splitting and recombination of the excitation pole pair windings and current commutation. Embodiment 2

[0085] The motor body structure of this embodiment is the same as that of Embodiment 1. The outer rotor is composed of two semi-circular permanent magnets butt-jointed. The joints of the two permanent magnets are respectively located at the due north and due south positions (the zero o'clock and six o'clock positions of the clock). The stator has twenty-four tooth poles, which are respectively marked as tooth pole 1 to tooth pole 24 . The central angle between the center lines of adjacent tooth poles is 15°. Tooth poles with a central angle of 180° to each other wind an excitation winding to form twelve excitation pole pairs. The encoder is used as the position sensor for the rotation of the motor rotor. See Appendix Figure 21 .

[0086] The circuit principle block diagram of the motor drive control device in this embodiment is as shown in Appendix Figure 20 . Any of the twelve H-bridge DC solid-state drive relays can be replaced by twelve H-bridge DC drive chips.

[0087] The twelve excitation pole pair windings of the stator are electrically connected to the twelve H-bridge DC solid-state drive relays respectively through the wiring port 111.

[0088] In this embodiment, two types of unit single-chip microcontrollers 106 combine the twelve field pole pairs of the stator into a current-maintaining field pole pair unit (hereinafter referred to as Unit A) and a current-reversing field pole pair unit (hereinafter referred to as Unit B). In this embodiment, at different times, the combination ratio of the number of field pole pairs included in Unit A and the number of field pole pairs included in Unit B is variable and controllable. The specific ratio of Unit A to Unit B is shown in the following table:

[0089]

[0090] When Unit A is (11), eleven field pole pair windings maintain the current, and Unit B is (1), one field pole pair winding reverses the current. Eleven H-bridge DC solid-state drive relays continuously input drive current to Unit A, and one H-bridge DC solid-state drive relay reverses the current of Unit B. See Appendix Figure 21 , the rotor permanent magnet and the stator field teeth poles achieve magnetic balance twice before and after, and the rotation step angle of the motor rotor is 15°.

[0091] When Unit A is (10), ten field pole pair windings maintain the current, and Unit B is (2), two field pole pair windings reverse the current. Ten H-bridge DC solid-state drive relays continuously input drive current to Unit A, and two H-bridge DC solid-state drive relays reverse the current of Unit B. See Appendix Figure 22 , the rotation step angle of the motor rotor is 30°.

[0092] When Unit A is (9), nine field pole pair windings maintain the current, and Unit B is (3), three field pole pair windings reverse the current. Nine H-bridge DC solid-state drive relays continuously input drive current to Unit A, and three H-bridge DC solid-state drive relays reverse the current of Unit B. See Appendix Figure 23 , the rotation step angle of the motor rotor is 45°.

[0093] When Unit A is (8), eight field pole pair windings maintain the current, and Unit B is (4), four field pole pair windings reverse the current. Eight H-bridge DC solid-state drive relays continuously input drive current to Unit A, and four H-bridge DC solid-state drive relays reverse the current of Unit B. See Appendix Figure 24 , the rotation step angle of the motor rotor is 60°.

[0094] When Unit A is (7), seven field pole pair windings maintain the current, and Unit B is (5), five field pole pair windings reverse the current. Seven H-bridge DC solid-state drive relays continuously input drive current to Unit A, and five H-bridge DC solid-state drive relays reverse the current of Unit B. See Appendix Figure 25 , the rotation step angle of the motor rotor is 75°.

[0095] When the A unit is (6), the winding currents of six exciting pole pairs are maintained, and the B unit is (6), where the winding currents of six exciting pole pairs are commutated. Six H-bridge DC solid-state drive relays continuously input drive current to the A unit, and six H-bridge DC solid-state drive relays commutate the current of the B unit. See the appendix Figure 26 , the stepping angle of the motor rotor rotation is 90°.

[0096] When the A unit is (5), the winding currents of five exciting pole pairs are maintained, and the B unit is (7), where the winding currents of seven exciting pole pairs are commutated. Five H-bridge DC solid-state drive relays continuously input drive current to the A unit, and seven H-bridge DC solid-state drive relays commutate the current of the B unit. See the appendix Figure 27 , the stepping angle of the motor rotor rotation is 105°.

[0097] When the A unit is (4), the winding currents of four exciting pole pairs are maintained, and the B unit is (8), where the winding currents of eight exciting pole pairs are commutated. Four H-bridge DC solid-state drive relays continuously input drive current to the A unit, and eight H-bridge DC solid-state drive relays commutate the current of the B unit. See the appendix Figure 28 , the stepping angle of the motor rotor rotation is 120°.

[0098] When the A unit is (3), the winding currents of nine exciting pole pairs are commutated, and the B unit is (9), where the winding currents of three exciting pole pairs are maintained. Three H-bridge DC solid-state drive relays continuously input drive current to the A unit, and nine H-bridge DC solid-state drive relays commutate the current of the B unit. See the appendix Figure 29 , the stepping angle of the motor rotor rotation is 135°.

[0099] When the A unit is (2), the winding currents of two exciting pole pairs are maintained, and the B unit is (10), where the winding currents of ten exciting pole pairs are commutated. Two H-bridge DC solid-state drive relays continuously input drive current to the A unit, and ten H-bridge DC solid-state drive relays commutate the current of the B unit. See the appendix Figure 30 , the stepping angle of the motor rotor rotation is 150°.

[0100] When the A unit is (1), the winding current of one exciting pole pair is maintained, and the B unit is (11), where the winding currents of eleven exciting pole pairs are commutated. One H-bridge DC solid-state drive relay continuously inputs drive current to the A unit, and eleven H-bridge DC solid-state drive relays commutate the current of the B unit. See the appendix Figure 31 , the stepping angle of the motor rotor rotation is 165°.

[0101] In this embodiment, the number of exciting pole pairs in Unit A and Unit B is a variable, and different combinations of the numbers of Unit A and Unit B correspond to different step angles. Through the display operation device 100, the logic operation single-chip microcomputer 105, and the exciting pole pair editing combination in the motor drive control device to form two types of unit single-chip microcomputers 106, the quantitative relationship between Unit A and Unit B can be programmed or manually adjusted, so as to select and change the motor rotation step angle. Usually, when the motor starts, the step angle gradually increases from small, which can make the motor start smoothly and improve the torque. When the motor speed increases, the step angle also relatively increases. When the motor speed is stable, the step angle also remains relatively unchanged.

[0102] In this embodiment, the encoder serves as the position sensor 112 of the motor rotor, and this encoder is arranged on the shaft that rotates synchronously with the output shaft of the motor rotor. The encoder can be selected with a model of 360 (or an integral multiple) pulses per week. During the rotation of the motor rotor, the encoder outputs equally spaced pulses to the logic operation single-chip microcomputer 105. The logic operation single-chip microcomputer 105 controls the exciting pole pair editing combination to form two types of unit single-chip microcomputers 106 to edit and combine new current-maintaining exciting pole pairs and new current-commutating exciting pole pairs in real time according to the number of encoder pulses received and the pre-set program, and simultaneously controls the driving current to continue in the new current-maintaining exciting pole pairs and commutate in the new current-commutating exciting pole pairs, performing self-closed-loop correction control on the operating state of the equipment.

[0103] In this embodiment, according to the coordinate angular positions of the current-maintaining exciting pole pairs and the current-commutating exciting pole pairs and each permanent magnet on the rotor, the magnitudes of the positive and negative currents input to the current-maintaining exciting pole pairs and the current-commutating exciting pole pairs can be closed and adjusted in real time, so as to minimize the input current, save energy, and improve the working efficiency of the motor under the condition of meeting the operating requirements of the motor equipment.

[0104] The driving principle and operation mechanism of the motor in this embodiment are similar to those in Embodiment 1, and will not be elaborated here. Embodiment 3

[0105] The outer rotor of this embodiment is formed by butt-jointing four arc-shaped permanent magnets. Refer to the appendix Figure 32 , the number of stator teeth is twenty-four, there are a total of twelve exciting pole pairs, each exciting pole pair is wound with an exciting winding, the central angle corresponding to each arc-shaped permanent magnet is 90°, and the number of stator teeth in the central angle range corresponding to each arc-shaped permanent magnet is six. Three position sensors AX, BX, and CX are arranged at intervals of 30° central angle.

[0106] When the motor drive control circuit inputs positive current to all exciting windings, the magnetic polarities of the stator teeth are as shown in the appendix Figure 32 , and the rotor and the stator are in magnetic balance, that is, the magnetic circuit is in the shortest state.

[0107] In this embodiment, six excitation pole pairs within the central angle range corresponding to the same permanent magnet are grouped. Four excitation pole pairs are combined into a current-maintaining excitation pole pair unit, and two excitation pole pairs are combined into a current-reversing excitation pole pair unit. In this way, a total of two current-maintaining excitation pole pair units and two current-reversing excitation pole pair units are formed. Refer to the appendix Figure 33 , and the step angle of the motor rotor is 30°.

[0108] In this embodiment, there are six excitation pole pairs within the central angle range corresponding to the same permanent magnet. Four excitation pole pairs are combined into a current-maintaining excitation pole pair unit, and two excitation pole pairs are combined into a current-reversing excitation pole pair unit. In this way, a total of two current-maintaining excitation pole pair units and two current-reversing excitation pole pair units are formed.

[0109] The motor drive principle and operation mechanism of this embodiment are similar to those of Embodiment 1. The difference is that in this embodiment, since the magnetic polarities of the rotor permanent magnet pairs are the same, that is, the inner arc surfaces of the arc-shaped permanent magnets are all S poles or all N poles, the magnetic polarities of the tooth poles of the same excitation pole pair on the stator are also the same.

[0110] The steps of the motor in this embodiment from startup to the rotor rotating a 30° step angle are as shown in the appendix Figure 31 to the appendix Figure 35 as shown.

[0111] The motor drive control device of this embodiment is as shown in the appendix Figure 20 as shown.

[0112] The motor drive principle and operation mechanism of this embodiment are similar to those of Embodiment 1 and will not be elaborated here. Embodiment 4

[0113] The outer rotor of this embodiment is formed by butt-jointing six arc-shaped permanent magnets. Refer to the appendix Figure 36 . The number of stator tooth poles is twenty-four, and there are a total of twelve excitation pole pairs. Each excitation pole pair is wound with an excitation winding. The central angle corresponding to each arc-shaped permanent magnet is 60°, and the number of stator tooth poles within the central angle range corresponding to each arc-shaped permanent magnet is four. Four excitation pole pairs within the central angle range corresponding to the same permanent magnet are grouped. Three excitation pole pairs are combined into a current-maintaining excitation pole pair unit, and one excitation pole pair is a current-reversing excitation pole pair unit. In this way, a total of three current-maintaining excitation pole pair units and three current-reversing excitation pole pair units are formed. Four position sensors AX, BX, CX, and DX are arranged at intervals of 15° central angle.

[0114] When the motor drive control circuit inputs positive current to all excitation windings, the magnetic polarities of the stator tooth poles are as shown in the appendix Figure 36 , and the rotor and the stator are in magnetic balance, that is, the magnetic path is in the shortest state.

[0115] In this embodiment, there are four excitation pole pairs within the central angle range corresponding to the same permanent magnet. Three excitation pole pairs are combined into a current-maintaining excitation pole pair unit, and one excitation pole pair is a current-commutating excitation pole pair unit. In this way, a total of three current-maintaining excitation pole pair units and three current-commutating excitation pole pair units are formed. See Appendix Figure 37 , tooth poles 2 to 4 and tooth poles 14 to tooth poles 16 , tooth poles 6 to 8 and tooth poles 18 to tooth poles 20 , tooth poles 10 to tooth poles 12 and tooth poles 22 to tooth poles 24 are combined into a current-maintaining excitation pole pair unit, and tooth poles 1 and tooth poles 13、 tooth poles 5 and tooth poles 17 , tooth poles 9 and tooth poles 21 are combined into a current-commutating excitation pole pair unit.

[0116] The first two steps of the motor in this embodiment from startup to the rotor rotating a 15° step angle are shown in Appendix Figure 36 to Appendix Figure 37 . Step 3 is the magnetic polarity state when the current of the current-commutating excitation pole pair unit (B unit) reverses, similar to Appendix Figure 34 . Step 4 is that the motor rotor rotates 15°, and the rotor permanent magnet and the stator excitation pole pair reach the magnetic balance magnetic polarity state, similar to Appendix Figure 35 .

[0117] The motor drive control device of this embodiment is shown in Appendix Figure 20 .

[0118] The motor drive principle and operation mechanism of this embodiment are similar to those of Embodiment 1 and will not be elaborated here.

[0119] The above embodiments are only partial embodiments of the technical solution of the present invention. When the motor has a large volume, the number of rotor permanent magnet pole pairs and the number of stator excitation pole pairs (the number of tooth poles) also increase accordingly; when the motor has a small volume, the number of rotor permanent magnet pole pairs and the number of stator excitation pole pairs also decrease accordingly, but the drive principle and operation mechanism of the motor are the same as those of the above embodiments. When the motor is an inner rotor and the stator excitation pole pair tooth poles surround the permanent magnet pole pairs, when the magnetic polarity of the stator excitation pole pair tooth poles within the central angle range corresponding to the rotor permanent magnet is different from the magnetic polarity of the outer arc surface of the permanent magnet, magnetic balance is achieved, and the drive principle and operation mechanism of the motor are still similar to those of the above embodiments.

Claims

1. A dynamic-phase permanent magnet brushless DC motor, which comprises a motor body and a drive control device, is characterized in that: The rotor of the motor body is composed of an even number of arc-shaped permanent magnets. For the even number of arc-shaped permanent magnets, the inner arc surfaces of half of the arc-shaped permanent magnets are N poles and the outer arc surfaces are S poles, while the inner arc surfaces of the other half of the arc-shaped permanent magnets are S poles and the outer arc surfaces are N poles. The permanent magnets with N-pole inner arc surfaces are butt-jointed with the permanent magnets with S-pole inner arc surfaces to form a circular ring and are fixed to the magnetic-conductive rotor frame. The stator of the motor body is composed of a stator base, tooth poles, excitation windings, and a position sensor. An even number of tooth poles are evenly distributed in a circular shape on the stator base. Tooth slots are provided between the tooth poles, and the central angles between the center lines of adjacent tooth poles are the same. Two tooth poles with a central angle of 180° are wound with the same excitation winding to form an excitation pole pair. The drive control device includes a stator excitation pole pair winding connection port, a switch drive circuit, a single-chip microcomputer, and a power supply. The stator excitation pole pair winding connection port is electrically connected to both the switch drive circuit and the stator excitation pole pair winding. The single-chip microcomputer is electrically connected to both the switch drive circuit and the position sensor. The single-chip microcomputer receives the rotor rotation angle signal given by the position sensor and, through the switch drive circuit, combines and edits the stator excitation pole pair windings into two types of excitation pole pair units. One type is the current-maintaining excitation pole pair unit, and the other type is the current-reversing excitation pole pair unit. At the same time, the single-chip microcomputer also controls the switch drive circuit to continuously provide a forward drive current to the current-maintaining excitation pole pair unit in real time, while providing a reverse drive current to the current-reversing excitation pole pair unit. Each time the single-chip microcomputer receives a signal from the position sensor, it immediately re-combines and edits the stator excitation pole pair windings through the drive switch circuit and continuously provides a forward drive current to the newly combined current-maintaining excitation pole pair unit and a reverse drive current to the newly combined current-reversing excitation pole pair unit.

2. The dynamic-phase permanent magnet brushless DC motor according to claim 1, wherein: The number of stator tooth poles and tooth slots is both twenty-four. The central angle between the radial center lines of adjacent tooth poles is 15°. An excitation winding is arranged in the tooth slots of two tooth poles whose radial center line central angles are 180° to each other, thus forming twelve excitation pole pairs. The outer rotor of the motor body is composed of two arc-shaped permanent magnets, or four arc-shaped permanent magnets, or six arc-shaped permanent magnets, or more than eight even numbers of arc-shaped permanent magnets and a cylindrical magnetic-conductive rotor frame. The arc-shaped permanent magnets are butt-jointed with each other to form a cylindrical shape and are fixed on the inner surface of the cylindrical magnetic-conductive rotor frame. The magnetic polarities of adjacent permanent magnets in the cylindrical permanent magnet are different, that is, the arc-shaped permanent magnet with an N-pole inner arc surface and an S-pole outer arc surface is butt-jointed with the arc-shaped permanent magnet with an S-pole inner arc surface and an N-pole outer arc surface.

3. A dynamic-phase permanent magnet brushless DC motor according to claim 1, characterized in that: The position sensor is a number of Hall position sensors. The Hall position sensors are installed on the stator base and are arranged near the butt joint of two permanent magnets with different magnetic polarities on the rotor.

4. A dynamic-phase permanent magnet brushless DC motor according to claim 1, characterized in that: The position sensor is an encoder, and the encoder is arranged on the shaft that rotates synchronously with the output shaft of the motor rotor.

5. A dynamic-phase permanent magnet brushless DC motor according to claim 1, characterized in that: The drive control device further includes a display operation device, which includes a display screen and an operation panel. The power supply includes a control power supply and a drive power supply. The switch drive circuit is composed of several H-bridge DC solid-state drive relays. The H-bridge DC solid-state drive relays are electrically connected to the lead-out wires of each field pole pair winding of the motor body stator through the lead-out wire connection ports of the field poles. Each field pole pair winding of the motor body stator is connected to an H-bridge DC solid-state drive relay. The single-chip microcomputer is divided into a field pole pair ratio logic editing single-chip microcomputer and a logic operation single-chip microcomputer. There are two control signal lines between the field pole pair ratio logic editing single-chip microcomputer and each H-bridge DC solid-state drive relay circuit. One is the control positive current signal line, and the other is the control negative current signal line. The field pole pair ratio logic editing single-chip microcomputer is also electrically connected to the display operation device and the logic operation single-chip microcomputer. The logic operation single-chip microcomputer is also electrically connected to the display operation device. The control power supply provides low-voltage weak electricity for the single-chip microcomputer and the display operation device. The drive power supply provides drive electric energy for the field pole pair windings through the H-bridge DC solid-state drive relays. The field pole pair ratio logic editing single-chip microcomputer, in accordance with the manual editing combination instruction issued by the display control device, combines all the field pole pair windings of the stator into two types of field pole pair winding units. One type is the current-maintaining field pole pair winding unit, and the other type is the current-reversing field pole pair winding unit. The field pole pair ratio logic editing single-chip microcomputer also receives the instruction of the logic operation control single-chip microcomputer and continuously provides a positive drive current to the current-maintaining field pole pair winding unit and a negative drive current to the current-reversing field pole pair winding unit in real time through the H-bridge DC solid-state drive relays. The timing of providing the negative drive current to the current-reversing field pole pair winding unit is associated with the rotor rotation angle. The position sensor sends the rotor rotation angle information to the logic operation control single-chip microcomputer, thereby realizing the closed-loop control between the rotor rotation angle and the editing combination of the field pole pair windings and the provision of the drive current. Each time the position sensor sends a signal, the single-chip microcomputer re-edits and combines each field pole pair winding, and the coordinate positions of the teeth of the newly edited and combined current-maintaining field pole pair winding unit and current-reversing field pole pair winding unit will deflect to the new coordinate positions.

6. A driving control method for a dynamic-phase permanent magnet DC brushless motor, characterized in that: The described dynamic-phase permanent magnet DC brushless motor comprises a motor body and a drive control device, and is characterized in that: the rotor of the motor body is composed of an even number of arc-shaped permanent magnets. For half of the even number of arc-shaped permanent magnets, the inner arc surface is an N pole and the outer arc surface is an S pole; for the other half of the arc-shaped permanent magnets, the inner arc surface is an S pole and the outer arc surface is an N pole. The permanent magnets with the inner arc surface being an N pole are butted against the permanent magnets with the inner arc surface being an S pole to form a circular ring and are fixed to the magnetic conductor rotor frame. The stator of the motor body is composed of a stator base, tooth poles, excitation windings and a position sensor. An even number of tooth poles are evenly distributed in a circular ring on the stator base. Tooth slots are arranged between the tooth poles. The central angle degrees between the center lines of adjacent tooth poles are the same. Two tooth poles with a central angle degree of 180° are wound with the same excitation winding to form an excitation pole pair. The drive control device includes a stator excitation pole pair winding connection port, a switch drive circuit, a single-chip microcomputer, a position sensor and a power supply. The stator excitation pole pair winding connection port is electrically connected to both the switch drive circuit and the stator excitation pole pair winding. The single-chip microcomputer is electrically connected to both the switch drive circuit and the position sensor. The single-chip microcomputer receives the rotor rotation angle signal given by the position sensor and, through the switch drive circuit, edits and combines the stator excitation pole pairs into two types of excitation pole pair units, one type is the current-maintaining excitation pole pair unit and the other type is the current-reversing excitation pole pair unit. At the same time, the single-chip microcomputer also controls the switch drive circuit to continuously provide a forward drive current to the current-maintaining excitation pole pair unit in real time, and provide a reverse drive current to the current-reversing excitation pole pair unit. Each time the position sensor sends a signal, the single-chip microcomputer and the switch drive circuit re-edit and combine the stator excitation pole pairs, and the coordinate positions of the tooth poles of the newly edited and combined current-maintaining excitation pole pair unit and current-reversing excitation pole pair unit will also change once; When a forward current is simultaneously input to the current-maintaining excitation pole pair winding unit and the current-reversing excitation pole pair unit with the same central angle within the central angle range corresponding to each permanent magnet, the magnetic polarities presented by the tooth poles of the current-maintaining excitation pole pair winding unit and the current-reversing excitation pole pair unit are different from the magnetic polarities of the permanent magnets they face. The tooth poles of the current-maintaining excitation pole pair unit and the current-reversing excitation pole pair unit form the shortest closed magnetic circuit with the permanent magnets they face. The rotor permanent magnets and the stator tooth poles reach magnetic balance, and the relative positions between the rotor and the stator remain unchanged; When the exciting pole pair unit closest to the counterclockwise direction of the butt joint of adjacent permanent magnets is set as the current commutation exciting pole pair unit, when the current of this current commutation exciting pole pair unit is commutated, the magnetic polarity of the teeth and poles of this current commutation exciting pole pair unit will change. And for the current-maintaining exciting pole pair units within the corresponding central angle range of the same permanent magnet, since the current direction remains unchanged, the magnetic polarity of their teeth and poles is different from that of the teeth and poles of the current commutation exciting pole pair unit closest to the rear end in the counterclockwise direction, and is the same as that of the teeth and poles of the current commutation exciting pole pair unit closest to the front end in the counterclockwise direction. At this moment, the coordinate positions of the teeth and poles with the same magnetic polarity are deflected counterclockwise compared to the coordinate positions of the teeth and poles with the same magnetic polarity in the previous magnetic balance state. The magnetic balance between the rotor permanent magnet and the stator teeth and poles is broken, and the magnetic force lines are distorted and elongated. Since the magnetic force lines follow the law of the shortest closed loop, it forces the rotor permanent magnet to rotate counterclockwise to achieve the magnetic balance between the rotor permanent magnet and the stator teeth and poles again; Once the magnetic balance is achieved again between the rotor permanent magnet and the stator teeth and poles, the position sensor sends a signal to the single-chip microcomputer and the switch drive circuit. The single-chip microcomputer and the switch drive circuit re-edit and combine the stator exciting pole pairs again, and once again set the exciting pole pair unit closest to the counterclockwise direction of the butt joint of adjacent permanent magnets as the new current commutation exciting pole pair unit, and set the other exciting pole pairs within the corresponding central angle range of the same permanent magnet as the new current-maintaining exciting pole pair units. After the current of this current commutation exciting pole pair unit is commutated, the above process is repeated. The coordinate positions of the teeth and poles with the same magnetic polarity are deflected counterclockwise again. The magnetic balance between the rotor permanent magnet and the stator teeth and poles is broken, and the magnetic force lines are distorted and elongated. Since the magnetic force lines follow the law of the shortest closed loop, it forces the rotor to rotate counterclockwise, and the magnetic balance is achieved again between the rotor permanent magnet and the stator teeth and poles; By continuously repeating the above process, a rotating magnetic field in the counterclockwise direction is formed on the teeth and poles of the stator exciting pole pairs, thereby driving the rotor permanent magnet to rotate synchronously counterclockwise; Similarly, when the single-chip microcomputer and the switch drive circuit set the exciting pole pair unit closest to the clockwise direction of the butt joint of the permanent magnet as the current commutation exciting pole pair unit, and set the other exciting pole pairs within the corresponding central angle range of the same permanent magnet as the current-maintaining exciting pole pair units, under this setting condition, the rotor rotates in the clockwise direction; The number of exciting pole pairs combined by the current-maintaining exciting pole pair units and the current commutation exciting pole pair units respectively facing each other within the corresponding central angle range of each permanent magnet of the rotor is manually set and corrected, or preset by the single-chip microcomputer programming, or automatically adjusted in real-time closed-loop by the single-chip microcomputer according to the operating state of the motor.

7. A dynamic-phase permanent magnet DC brushless motor drive control method according to claim 6, characterized in that: The method for the single-chip microcomputer to make real-time adjustment according to the operating state of the motor is as follows: First, when the motor starts, the number of exciting pole pairs set for the exciting pole pair unit closest to the permanent magnet docking point is small. That is, within the central angle range corresponding to the same permanent magnet, the ratio of the number of exciting pole pairs set for the exciting current maintaining pole pair unit to the number of exciting pole pairs set for the current commutation exciting pole pair unit is relatively large. After the motor starts, as the motor load changes or the speed increases, the single-chip microcomputer gradually adjusts the number of exciting pole pairs set for the current commutation exciting pole pair commutation unit closest to the permanent magnet docking point, so that the ratio of the number of exciting pole pairs set for the exciting current maintaining pole pair unit to the number of exciting pole pairs set for the current commutation exciting pole pair unit reaches the best matching state with the operating equipment until the motor reaches it. Second, according to the coordinate angular positions of the exciting current maintaining pole pair unit and the current commutation exciting pole pair unit and each permanent magnet on the rotor, the magnitude of the positive and negative currents input to the exciting current maintaining pole pair unit and the current commutation exciting pole pair unit is turned off or adjusted in real time, so as to minimize the input current, save energy and improve the working efficiency of the motor under the condition of meeting the operating requirements of the motor equipment.

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