Switch permanent magnet energy-saving motor

Abstract

The switch permanent magnet energy-saving motor comprises a direct current power supply, a driving unit and a motor, the motor comprises a stator iron core, a magnetic pole winding, a rotor iron core and a rotor shaft, an inner ring of the stator iron core is provided with a stator magnetic pole, the magnetic pole winding is wound on the stator magnetic pole, and the rotor shaft is wound on the rotor iron core. The low-rotation-speed high-torque and high-rotation-speed low-torque running mode has the low-rotation-speed high-torque running mode and the high-rotation-speed low-torque running mode at the same time, has the advantages of energy conservation and high efficiency, and can be widely applied to the fields of electric automobiles, power transmission, rotating machinery and the like.

Description

Technical Field

[0001] The invention belongs to the category of electromechanical transmission, relates to the technical field of electric motors, and in particular to a switch permanent magnet energy-saving motor. Background Art

[0002] With the advancement of science and technology and the continuous development of the economy, the dependence of various fields on energy has become more and more obvious. Energy conservation and emission reduction have become an important tool to improve the competitiveness of countries around the world, and have been widely studied and implemented in different industries. Electricity, which accounts for a large proportion of many energy sources, is an indispensable energy source in industrial and commercial activities. How to improve the technical level of major energy-consuming equipment and increase electricity production has become a common research topic for experts and scholars from all over the world.

[0003] According to relevant statistics, the electric energy consumption of electric motors currently accounts for more than 60% of my country's electric energy consumption. Electric motors are widely used in port lifting, petroleum, metallurgy, mining, transportation and other industries. Traditional electric motors have obvious disadvantages such as high energy consumption, high failure rate and low transmission efficiency. Especially for electric vehicles, which are powered by on-board power supply, high efficiency and energy saving are particularly important. Reducing the electric energy consumption of electric motors can also directly improve the endurance of electric vehicles. Therefore, it is urgent to develop new energy-saving, high-efficiency and high-performance motors. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a switch permanent magnet energy-saving motor with simple structure, low energy consumption and high operating efficiency, which includes a DC power supply, a drive unit and a motor, and is characterized in that: the DC power supply is connected to the motor through the drive unit; The speed control of the drive unit adopts square wave excitation control of a three-phase full-bridge circuit structure, and the torque control adopts thyristor chopper voltage stabilization control; The motor comprises a stator core, a magnetic pole winding, a rotor core and a rotor shaft. The stator core comprises a stator yoke and a stator magnetic pole arranged on the inner ring of the stator yoke. A magnetic pole winding is wound on each stator magnetic pole, and the magnetic pole windings are connected to form a phase winding. The rotor core comprises a rotor yoke, a rotor magnetic pole and a permanent magnet. A rotor magnetic pole is arranged on the outer ring of the rotor yoke. A rotor slot is formed between two adjacent rotor magnetic poles. The permanent magnets are embedded in the rotor slots in a method that the polarities of adjacent permanent magnets are the same. The magnetized rotor magnetic poles are distributed in NSNS… magnetic polarity. The rotor magnetic poles are composed of a rotor pole boss and rotor pole skew arcs on both sides. The radial section width of the rotor pole boss is not greater than the radial section width of the stator magnetic pole. The radial section edge of the rotor pole skew arc is formed into an inverse parabola to highlight the rotor pole boss. The number of stator magnetic poles is a multiple of 3, and the number of rotor magnetic poles is an even number. The torque control unit adjusts the duty cycle of the input pulse to the thyristor base through the torque signal sent by the torque sensor installed on the motor and the current signal and voltage signal fed back from the drive unit, controls the on and off time of the thyristor, and the freewheeling of the freewheeling diode to provide the system with continuously adjustable DC current; The speed control unit obtains a continuously adjustable motor rotation speed by controlling the switching cycle time of the insulated gate bipolar transistor of the drive unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 It is a radial cross-sectional view of a 12 / 8 motor in an embodiment of the present invention; Figure 2 This is a circuit connection block diagram of the present invention; Figure 3 This is a connection diagram of the stator winding of a motor in an embodiment of the present invention; Figure 4 The stator and rotor states of the insulated gate bipolar transistors T1 and T4 when they are turned on in the embodiment of the present invention; Figure 5 The stator and rotor states of the insulated gate bipolar transistors T1 and T4 after they are turned on in the embodiment of the present invention; Figure 6 The stator and rotor states when the insulated gate bipolar transistors T1 and T6 are turned on in the embodiment of the present invention; Figure 7 The stator and rotor states of the insulated gate bipolar transistors T1 and T6 after they are turned on in the embodiment of the present invention; Figure 8 The stator and rotor states when the insulated gate bipolar transistors T3 and T6 are turned on in the embodiment of the present invention; Fig. 9 The stator and rotor states of the insulated gate bipolar transistors T3 and T6 after they are turned on in the embodiment of the present invention; Fig.10 The stator and rotor states when the insulated gate bipolar transistors T2 and T3 are turned on in the embodiment of the present invention; Fig.11 The stator and rotor states of the insulated gate bipolar transistors T2 and T3 after they are turned on in the embodiment of the present invention. Fig.12 The stator and rotor states when the insulated gate bipolar transistors T2 and T5 are turned on in the embodiment of the present invention; Fig.13 The stator and rotor states of the insulated gate bipolar transistors T2 and T5 after they are turned on in the embodiment of the present invention; Fig.14 The stator and rotor states when the insulated gate bipolar transistors T4 and T5 are turned on in the embodiment of the present invention; Fig.15 This is the state of the stator and rotor after the insulated gate bipolar transistors T4 and T5 are turned on in the embodiment of the present invention.

[0006] In the figure: 1. DC power supply, 2. speed control unit, 3. motor, 4. stator core, 5. rotor core, 6. stator pole, 7. pole winding, 8. rotor pole, 9. magnetic isolation sleeve, 10. rotor shaft, 11. permanent magnet, 12. rotor pole boss, 13. rotor pole skew arc, 14. magnetic detector, C. voltage stabilizing capacitor, D. freewheeling diode, D1~D6. fast recovery diode, T. thyristor, T1~T6 insulated gate bipolar transistors, k. star point electronic switch, k1. A phase electronic switch, k2. B phase electronic switch, k3. C phase electronic switch. DETAILED DESCRIPTION

[0007] The following will be combined with the drawings of the present application to clearly and completely describe the technical solution of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0008] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "positive", "negative", "vertical", "horizontal", "top", "bottom", "inside", "outside", "one side", "one end", "one side" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.

[0009] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense; they can be mechanical connections or electrical connections; they can be directly connected or indirectly connected through an intermediate medium, and they can be internal connections between two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0010] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0011] It should also be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this specification and the appended claims, the singular forms "a", "an" and "the" are intended to include plural forms unless the context clearly indicates otherwise.

[0012] It should be further understood that the term "and / or" used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0013] The accompanying drawings show various schematic diagrams of structures according to the embodiments disclosed in the present application. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may further design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0014] Referring to the drawings, the present application discloses a switch permanent magnet energy-saving motor, comprising a DC power supply 1, a drive unit 2, and a motor 3, wherein the DC power supply 1 is connected to the motor 3 via the drive unit 2; The speed control of the drive unit 2 adopts square wave excitation control of a three-phase full-bridge circuit structure, and the torque control adopts thyristor T chopper voltage stabilization control; The motor 3 comprises a stator core 4, a magnetic pole winding 7, a rotor core 5 and a rotor shaft 10. The stator core 4 comprises a stator yoke and a stator magnetic pole 6 arranged on the inner ring of the stator yoke, and each stator magnetic pole 6 is wound with a magnetic pole winding 7; the rotor core 5 comprises a rotor yoke, a rotor magnetic pole 8 and a permanent magnet 11. The rotor magnetic pole 8 is arranged on the outer ring of the rotor yoke, and a rotor slot is formed between two adjacent rotor magnetic poles. The permanent magnet 11 is embedded in the rotor slot in a method that the polarities of adjacent permanent magnets are the same, and the magnetized rotor magnetic poles are distributed in NSNS... magnetic polarity; The rotor poles are composed of a rotor pole boss 12 and rotor pole skew arcs 13 on both sides. The radial section width of the rotor pole boss 12 is not greater than the radial section width of the stator pole 6. The radial section edge of the rotor pole skew arc 13 is an inverted parabola, highlighting the rotor pole boss 12. The number of stator poles is a multiple of 3, and the number of rotor poles is an even number.

[0015] The torque control of the drive unit 2 is controlled by the torque control unit. The torque control unit adjusts the duty cycle of the input pulse to the base of the thyristor T through the torque signal sent by the torque sensor installed on the motor and the current signal and voltage signal fed back from the drive unit 2, controls the on and off time of the thyristor T, and the freewheeling of the freewheeling diode D to provide the system with a continuously adjustable DC current; The speed control unit obtains a continuously adjustable motor rotation speed by controlling the switching cycle time of the insulated gate bipolar transistor of the drive unit 2 .

[0016] The speed control of the drive unit 2 adopts square wave excitation control with a three-phase full-bridge as the main circuit structure, and the torque control adopts thyristor T chopper voltage stabilization control.

[0017] The insulated gate bipolar transistor T1 is connected in parallel with the reverse-connected fast recovery diode D1, and in series with the insulated gate bipolar transistor T2, and is connected to the A-phase winding of the motor 3, and is connected to the A-phase terminal of the magnetic detector 14 via the A-phase electronic switch k1, and the insulated gate bipolar transistor T2 is connected in parallel with the reverse-connected fast recovery diode D2; the insulated gate bipolar transistor T3 is connected in parallel with the reverse-connected fast recovery diode D3, and is connected in series with the insulated gate bipolar transistor T4, and is connected to the B-phase winding of the motor 3, and is connected to the B-phase terminal of the magnetic detector 14 via the B-phase electronic switch k2, and the insulated gate bipolar transistor T4 is connected in parallel with the reverse-connected fast recovery diode D4; the insulated gate bipolar transistor T5 is connected in parallel with the reverse-connected fast recovery diode D5, and is connected in series with the insulated gate bipolar transistor T6, and is connected to the C-phase winding of the motor 3, and is connected to the C-phase terminal of the magnetic detector 14 via the C-phase electronic switch k3, and the insulated gate bipolar transistor T6 is connected in parallel with the reverse-connected fast recovery diode D6.

[0018] The pole windings 7 are arranged in the order of A, B, C, A, B, C..., and each three A, B, C are connected at the tail ends to form a short-circuited pole winding, and the short-circuited tap of any group of pole windings is led to the star point terminal of the magnetic detector 14 through the star point electronic switch k.

[0019] Each pole winding has the same number of turns, wire diameter, and winding direction. Figure 3 As shown, the pole windings 7 are connected to form phase windings.

[0020] Before the motor starts running, the magnetic detector 14 sends pulse signals to the A, B, and C pole windings 7 through the star point electronic switch k, the A phase electronic switch k1, the B phase electronic switch k2, and the C phase electronic switch k3 respectively, and compares and detects the magnetic force and polarity of the three-phase windings. The stator pole 6 of the phase with the strongest detected N pole magnetic force is determined to correspond to the N pole rotor pole, and this position is set as the initial position.

[0021] When the motor is running, the stator magnetic pole 6 is the magnetic pole winding 7 corresponding to the N-pole rotor magnetic pole 8, and no power is supplied, and no magnetic field is established. The magnetic pole winding 7 adjacent to the rotation direction conducts a positive current, and establishes the same magnetic field as the S-pole rotor magnetic pole 8, generating a repulsive electromagnetic force. At the same time, the magnetic pole winding 7 adjacent to the rotation direction conducts a reverse current, and establishes a magnetic field opposite to the S-pole rotor magnetic pole 8, generating an attractive electromagnetic force. The rotor deflects under the action of the magnetic field, enters the S-pole rotor magnetic pole 8 and aligns with the next stator magnetic pole 6 in the rotation direction. After entering this position, the stator magnetic pole 6 The magnetic pole winding 7 corresponding to the S-pole rotor magnetic pole 8 is not energized and does not establish a magnetic field. The magnetic pole winding 7 adjacent to the rotating direction conducts a reverse current to establish a magnetic field identical to the N-pole rotor magnetic pole 8, generating a repulsive electromagnetic force. At the same time, the magnetic pole winding 7 adjacent to the rotating direction conducts a positive current to establish a magnetic field opposite to the N-pole rotor magnetic pole 8, generating an attractive electromagnetic force. The rotor deflects under the action of the magnetic field and enters the N-pole rotor magnetic pole 8 to align with the next stator magnetic pole 6 in the rotating direction. This cycle is repeated to form an electromagnetic torque, converting electrical energy into mechanical energy. Combined with the attached drawings, take a 12 / 8-pole motor as an example: the 3-phase winding of the motor is star-connected, combined with square wave control, to generate continuous positive torque to ensure the normal operation of the motor 3, every 90° is a power-on cycle of the motor, every 15° phase change, three-phase square wave control: such a cycle, each cycle conducts 90° mechanical angle; Among them, the motor initial position 0° is set to the position where the C-phase stator pole 6 is aligned with the N-pole rotor pole 8. When the insulated gate bipolar transistors T1 and T4 are turned on, the rotor position is 0°→15°, and the motor winding current direction is A→B; when the insulated gate bipolar transistors T1 and T6 are turned on, the rotor position is 15°→30°, and the motor winding current direction is A→C; when the insulated gate bipolar transistors T3 and T6 are turned on, the rotor position is 30°→45°, and the motor winding current direction is B→C; when the insulated gate bipolar transistors T2 and T3 are turned on, the rotor position is 45°→60°, and the motor winding current direction is B→A; when the insulated gate bipolar transistors T2 and T5 are turned on, the rotor position is 60°→75°, and the motor winding current direction is C→A; when the insulated gate bipolar transistors T4 and T5 are turned on, the rotor position is 75°→90°, the motor winding current direction is C→B, and the motor rotates forward; The initial position of the motor 0° is set to the position where the C-phase stator pole 6 is aligned with the N-pole rotor pole 8. When the insulated gate bipolar transistors T2 and T3 are turned on, the rotor position is 0°→-15°, and the motor winding current direction is B→A; when the insulated gate bipolar transistors T3 and T6 are turned on, the rotor position is -15°→-30°, and the motor winding current direction is B→C; when the insulated gate bipolar transistors T1 and T6 are turned on, the rotor position is -30°→-45°, The direction of the motor winding current is A→C; when the insulated gate bipolar transistors T1 and T4 are turned on, the rotor position is -45°→-60°, and the direction of the motor winding current is A→B; when the insulated gate bipolar transistors T5 and T4 are turned on, the rotor position is -60°→-75°, and the direction of the motor winding current is C→B; when the insulated gate bipolar transistors T5 and T2 are turned on, the rotor position is -75°→-90°, the direction of the motor winding current is C→A, and the motor reverses.

[0022] Since the rotor position is not consistent before the motor starts, there are several situations: In the first case, the N pole of the rotor pole 8 is aligned with the C pole of the stator pole 6, and the magnetic detector 14 outputs a pulse test voltage to the pole winding 7, measures the degree of obstruction of the current passing through the pole winding 7, and determines the corresponding position of the aligned rotor pole 8 and the stator pole, as well as the corresponding polarity. After the determination is completed, the star point electronic switch k, the A phase electronic switch k1, the B phase electronic switch k2, and the C phase electronic switch k3 are disconnected, and the pole winding 7 is turned on in turn according to the steering requirements with the set insulated gate bipolar transistor switching sequence.The direction of the current in each pole winding can be known according to the right-hand screw rule and the law of electromagnetic force: the stator pole A is all S polarity, the stator pole B is all N polarity, the stator pole C is not energized and has no polarity, each stator pole A is the same polarity as each rotor pole S, and all generate repulsive electromagnetic force. At the same time, the stator pole B with N polarity generates an attractive electromagnetic force on the rotor pole S. Due to the unbalanced structure of the stator and rotor poles, the rotor rotating body rotates in the predetermined direction of the stator pole current, so that the S pole of the rotor pole 8 is aligned with the B pole of the stator pole 6; then proceed to the next step, change the conduction strategy of the insulated gate bipolar transistor so that the stator pole A is all S polarity, the stator pole C is all N polarity, the stator pole B is not energized and has no polarity, and each stator pole C is respectively aligned with each rotor pole N The same polarity generates repulsive electromagnetic force. At the same time, the stator pole A with N polarity generates attractive electromagnetic force on the rotor pole S. The rotor rotating body rotates in the predetermined direction of the stator pole current, so that the N pole of the rotor pole 8 is aligned with the A pole of the stator pole 6. Then, the next step is to change the conduction strategy of the insulated gate bipolar transistor so that the stator poles B are all S polarity, the stator poles C are all N polarity, the stator pole A is not energized and has no polarity, and each stator pole B is respectively aligned with each rotor pole S have the same polarity, and both produce repulsive electromagnetic force. At the same time, the stator pole C with N polarity produces attractive electromagnetic force on the rotor pole S. The rotor rotating body rotates in the predetermined direction of the stator pole current, so that the S pole of the rotor pole 8 is aligned with the C pole of the stator pole 6; then the next step is carried out to change the conduction strategy of the insulated gate bipolar transistor, the stator pole A is all N polarity, the stator pole B is all S polarity, the stator pole C is not energized and has no polarity, and each stator pole A is respectively aligned with each rotor pole N The same polarity generates repulsive electromagnetic force. At the same time, the stator pole B with S polarity generates attractive electromagnetic force on the rotor pole S. The rotor rotating body rotates in the predetermined direction of the stator pole current, so that the N pole of the rotor pole 8 is aligned with the B pole of the stator pole 6. Then, the next step is to change the conduction strategy of the insulated gate bipolar transistor, so that the stator poles C are all S polarity, the stator poles A are all N polarity, the stator poles B are not energized and have no polarity, and the stator poles C are respectively the same polarity as the rotor poles S, and all generate repulsive electromagnetic force. At the same time, the stator pole A with N polarity generates attractive electromagnetic force on the rotor pole S. The rotor rotating body rotates in the predetermined direction of the stator pole current, so that the N pole of the rotor pole 8 is aligned with the C pole of the stator pole 6. The above process is repeated, and the motor continuously converts electrical energy into mechanical energy, driving the load to do work.

[0023] In the second case, the S pole of the rotor pole 8 is aligned with the C pole of the stator pole 6, and the magnetic detector 14 outputs a pulse test voltage to the pole winding 7, measures the degree of obstruction of the current passing through the pole winding 7, and determines the corresponding position of the aligned rotor pole 8 and the stator pole, as well as the corresponding polarity. After the determination is completed, the star point electronic switch k, the A phase electronic switch k1, the B phase electronic switch k2, and the C phase electronic switch k3 are disconnected, and the pole winding 7 is turned on in turn according to the steering requirements with the set insulated gate bipolar transistor switching sequence; the current direction in each pole winding is that the stator pole A is N polarity, the stator pole B is S polarity, the stator pole C is not energized and has no polarity, and each stator pole A is respectively connected to each rotor pole N The same polarity generates repulsive electromagnetic force. At the same time, the stator pole B with S polarity generates attractive electromagnetic force on the rotor pole S. The rotor rotating body rotates in the predetermined direction of the stator pole current, so that the N pole of the rotor pole 8 is aligned with the B pole of the stator pole 6; then proceed to the next step, change the conduction strategy of the insulated gate bipolar transistor, so that the stator poles C are all S polarity, the stator poles A are all N polarity, the stator poles B are not powered and have no polarity, and each stator pole C is respectively the same polarity as each rotor pole S, and all generate repulsive electromagnetic force. At the same time, the stator pole A with N polarity generates attractive electromagnetic force on the rotor pole S, and the rotor rotating body rotates in the predetermined direction of the stator pole current, so that the N pole of the rotor pole 8 is aligned with the C pole of the stator pole 6; then proceed to the next step, the stator poles A are all S polarity, the stator poles B are all N polarity, the stator poles C are not powered and have no polarity, and each stator pole A is respectively aligned with each rotor pole S The same polarity generates repulsive electromagnetic force. At the same time, the stator pole B with N polarity generates attractive electromagnetic force on the rotor pole S. Due to the unbalanced structure of the stator and rotor poles, the rotor rotating body rotates in the predetermined direction of the stator pole current, so that the S pole of the rotor pole 8 is aligned with the B pole of the stator pole 6; then the next step is to change the conduction strategy of the insulated gate bipolar transistor so that the stator pole A is all S polarity, the stator pole C is all N polarity, the stator pole B is not energized and has no polarity, and each stator pole C is respectively aligned with each rotor pole N The same polarity generates repulsive electromagnetic force. At the same time, the stator pole A with N polarity generates attractive electromagnetic force on the rotor pole S. The rotor rotating body rotates in the predetermined direction of the stator pole current, so that the N pole of the rotor pole 8 is aligned with the A pole of the stator pole 6. Then, the next step is to change the conduction strategy of the insulated gate bipolar transistor, so that the stator poles B are all S polarity, the stator poles C are all N polarity, the stator pole A is not energized and has no polarity, and each stator pole B has the same polarity as each rotor pole S, and generates repulsive electromagnetic force. At the same time, the stator pole C with N polarity generates attractive electromagnetic force on the rotor pole S. The rotor rotating body rotates in the predetermined direction of the stator pole current, so that the S pole of the rotor pole 8 is aligned with the C pole of the stator pole 6. The above process is repeated, and the motor continuously converts electrical energy into mechanical energy, driving the load to do work.

[0024] In the third case, the N pole of the rotor pole 8 is aligned with the A pole of the stator pole 6. In the fourth case, the S pole of the rotor pole 8 is aligned with the A pole of the stator pole 6. In the fifth case, the N pole of the rotor pole 8 is aligned with the B pole of the stator pole 6. In the sixth case, the S pole of the rotor pole 8 is aligned with the B pole of the stator pole 6. The working strategy refers to the first and second cases and will not be repeated.

[0025] In the seventh case, when the N pole of the rotor pole 8 is aligned with the C pole of the stator pole 6 by not less than 50% and is offset in the opposite direction, the C phase pole winding and the A phase pole winding are passed through a positive current, and the B phase pole winding is passed through a reverse current, that is, the insulated gate bipolar transistors T1, T4, and T5 are turned on, so that the electromagnetic polarities of the stator pole A and the stator pole B are both S poles, and the C pole of the stator pole 6 and the rotor pole N generate an attractive electromagnetic force, while the A pole of the stator pole 6 and the rotor pole S generate a repulsive electromagnetic force, and the N pole of the rotor pole 8 is completely aligned with the C pole of the stator pole 6, and thereafter the magnetization sequence of the stator poles is cycled according to the above steps.

[0026] In the eighth case, when the N pole of the rotor pole 8 is aligned with the C pole of the stator pole 6 by not less than 50% and is offset in the positive direction, the C phase pole winding and the B phase pole winding are passed through the reverse current, and the A phase pole winding is passed through the forward current, that is, the insulated gate bipolar transistors T1, T4, and T6 are turned on, so that the electromagnetic polarities of the stator pole C and the stator pole B are both N poles, and the C pole of the stator pole 6 and the rotor pole N generate a repulsive electromagnetic force. At the same time, the B pole of the stator pole 6 and the rotor pole S generate an attractive electromagnetic force, and the S pole of the rotor pole 8 is completely aligned with the B pole of the stator pole 6. Thereafter, the magnetization sequence of the stator poles is cycled according to the above steps.

[0027] In the ninth case, when the alignment of the N pole of the rotor pole 8 with the stator pole 6 is less than 50%, due to the asymmetry of the number of stator and rotor poles, the alignment of the S pole of the rotor pole 8 with the stator pole 6 will exceed 50%. According to the above method, the conduction sequence of the insulated gate bipolar transistor is adjusted according to the S pole alignment method.

[0028] When the motor needs to be reversed, the current flowing through the pole winding 7 is opposite to the above situation.

[0029] The speed control of the motor 3 is achieved by controlling the switching cycle of the insulated gate bipolar transistor; the torque output of the motor 3 is controlled by the thyristor T and is independent of the speed of the motor 3. When the load torque fed back by the torque sensor increases, the thyristor T increases the system voltage, thereby increasing the current of the motor 3 winding. Conversely, the system voltage is reduced to reduce the current of the motor 3 winding. The current signal and voltage signal collected from the drive unit 2 are used to ensure that the voltage and current of the system are within a safe range.

[0030] A magnetic isolation sleeve 9 is installed between the rotor shaft 10 and the rotor pole 8 and the permanent magnet 11 to prevent magnetic leakage; pressure plates formed by non-magnetic processing with a tensile strength of 500-700Mpa and a yield strength of 345-360Mpa are provided at both ends of the rotor assembly.

[0031] The invention application can separately control the speed and torque of the motor. When the equipment is in the initial operating state, it operates at high torque and low speed. As the inertia increases, the torque output is gradually reduced, the operating speed is increased, and the full-speed operation state is entered. When operating at low load, the torque output will be further reduced without reducing the operating speed. The invention application has both low-speed and high-torque and high-speed and low-torque operating modes, which has the advantages of energy saving and high efficiency, and can be widely used in electric vehicles, power transmission, rotating machinery and other fields.

Claims

1. A switched permanent magnet energy-saving motor, comprising a DC power supply (1), a drive unit (2), and a motor (3), characterized in that: The DC power supply (1) is connected to the motor (3) via the drive unit (2); The speed control of the drive unit (2) adopts square wave excitation control of a three-phase full-bridge circuit structure, and the torque control adopts thyristor T chopper voltage stabilization control; The motor (3) comprises a stator core (4), a magnetic pole winding (7), a rotor core (5) and a rotor shaft (10), wherein the stator core (4) comprises a stator yoke and stator magnetic poles (6) arranged on the inner ring of the stator yoke, and the magnetic pole winding (7) is wound around each stator magnetic pole (6); the rotor core (5) comprises a rotor yoke, a rotor magnetic pole (8) and a permanent magnet (11), wherein the rotor yoke outer ring is provided with a rotor magnetic pole (8), and a rotor slot is formed between two adjacent rotor magnetic poles, and the permanent magnet (11) is embedded in the rotor slot in a manner that adjacent permanent magnets have the same polarity, and the magnetized rotor magnetic poles are distributed in an NSNS… magnetic polarity pattern; The rotor magnetic pole (8) is composed of a rotor pole boss (12) and rotor pole skew arcs (13) on both sides; the radial cross-sectional width of the rotor pole boss (12) is no greater than the radial cross-sectional width of the stator magnetic pole (6); and the radial cross-sectional edges of the rotor pole skew arc (13) are in the shape of an inverse parabola; the number of the stator magnetic poles (6) is a multiple of 3, and the number of the rotor magnetic poles (8) is an even number.

2. According to claim 1, a switch permanent magnet energy-saving motor, characterized in that: The torque control of the drive unit (2) is controlled by a torque control unit, which adjusts the duty cycle of the input pulse to the base of the thyristor T through the torque signal sent by the torque sensor installed on the motor and the current signal and voltage signal fed back from the drive unit (2), thereby controlling the on and off time of the thyristor T and the freewheeling of the freewheeling diode D to provide a continuously adjustable direct current to the system; The speed control unit obtains a continuously adjustable motor rotation speed by controlling the switching cycle time of the insulated gate bipolar transistor of the drive unit (2); The speed control of the drive unit (2) adopts square wave excitation control with a three-phase full-bridge as the main circuit structure, and the torque control adopts thyristor T chopper voltage stabilization control.

3. According to claim 1, a switch permanent magnet energy-saving motor, characterized in that: The magnetic pole windings (7) are arranged in the order of A, B, C, A, B, C..., and each group of three A, B, C are connected at their tail ends to form a short-circuited magnetic pole winding, and the short-circuited tap of any group of magnetic pole windings is led to the star point terminal of the magnetic detector (14) via a star point electronic switch k.

4. According to claim 1, a switch permanent magnet energy-saving motor, characterized in that: Each of the magnetic pole windings (7) has the same number of turns, the same wire diameter, and the same winding direction.

5. According to claim 1, a switch permanent magnet energy-saving motor, characterized in that: Before the motor (3) starts running, the magnetic force detector (14) sends pulse signals to the A, B, and C pole windings 7 respectively through the star point electronic switch k, the A phase electronic switch k1, the B phase electronic switch k2, and the C phase electronic switch k3, and compares and detects the magnetic force and polarity of the three-phase windings, and determines that the stator magnetic pole 6 of the phase with the strongest detected N pole magnetic force corresponds to the N pole rotor magnetic pole, and sets this position as the initial position; When the motor is running, the magnetic pole winding (7) corresponding to the stator magnetic pole (6) and the N-pole rotor magnetic pole (8) is not energized and does not establish a magnetic field. The magnetic pole winding (7) adjacent to the stator magnetic pole (6) in the rotation direction conducts a positive current to establish a magnetic field identical to the S-pole rotor magnetic pole (8), generating a repulsive electromagnetic force. At the same time, the magnetic pole winding (7) adjacent to the stator magnetic pole (6) in the rotation direction conducts a reverse current to establish a magnetic field opposite to the S-pole rotor magnetic pole (8), generating an attractive electromagnetic force. The rotor deflects under the action of the magnetic field and enters the S-pole rotor magnetic pole (8) to align with the next stator magnetic pole (6) in the rotation direction. After entering this position, The stator magnetic pole (6) is a magnetic pole winding (7) corresponding to the S-pole rotor magnetic pole (8), and no power is supplied to establish a magnetic field. The magnetic pole winding (7) adjacent to the stator magnetic pole (6) in the rotation direction conducts a reverse current to establish a magnetic field identical to that of the N-pole rotor magnetic pole (8), thereby generating a repulsive electromagnetic force. At the same time, the magnetic pole winding (7) adjacent to the stator magnetic pole (6) in the rotation direction conducts a forward current to establish a magnetic field opposite to that of the N-pole rotor magnetic pole (8), thereby generating an attractive electromagnetic force. The rotor is deflected under the action of the magnetic field, and enters the N-pole rotor magnetic pole (8) to align with the next stator magnetic pole (6) in the rotation direction. This cycle is repeated to form an electromagnetic torque.

6. According to claim 1, a switch permanent magnet energy-saving motor, characterized in that: The speed control of the motor (3) is achieved by controlling the switching cycle of the insulated gate bipolar transistor; the torque output of the motor (3) is controlled by the thyristor T and is independent of the speed of the motor (3); when the load torque fed back by the torque sensor increases, the thyristor T increases the system voltage, thereby increasing the winding current of the motor (3); conversely, the system voltage is reduced, thereby reducing the winding current of the motor (3).

7. According to claim 1, a switch permanent magnet energy-saving motor, characterized in that: A magnetic isolation sleeve (9) is installed between the rotor shaft (10) and the rotor magnetic poles (8) and the permanent magnets (11) to prevent magnetic leakage; and pressure plates formed by non-magnetic processing with a tensile strength of 500-700Mpa and a yield strength of 345-360Mpa are provided at both the front and rear ends of the rotor assembly.

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