Switching permanent magnet energy-saving motor

Abstract

The application discloses a kind of switch permanent magnet energy-saving motor, which can control the rotating speed and torque of motor separately, comprising a DC power supply, a driving unit and a motor.The motor comprises a stator core, a magnetic pole winding, a rotor core and a rotor shaft, the inner ring of the stator core is provided with a stator magnetic pole, the magnetic pole winding is wound on the stator magnetic pole, the outer ring of the rotor core is provided with a rotor magnetic pole, and the rotor magnetic pole is composed of a rotor pole boss and two rotor pole inclined arcs on both sides.The application has low speed and high torque, high speed and low torque operation mode, and has the advantages of energy saving and high efficiency, which can be widely used in electric vehicles, power transmission, rotary machinery and other fields.

Description

Technical Field

[0001] This invention belongs to the field of electromechanical transmission, and relates to the field of electric motor technology, and in particular to a switching permanent magnet energy-saving motor. Background Technology

[0002] With the advancement of science and technology and the continuous development of the economy, the dependence on energy in various sectors has become increasingly apparent. Energy conservation and emission reduction have become important tools for enhancing the competitiveness of countries worldwide, and have been widely studied and implemented across different industries. Electricity, which accounts for a large proportion of various energy sources, is an indispensable energy source for industrial and commercial activities. How to improve the technological level of major energy-consuming equipment while simultaneously increasing electricity production has become a common research topic for experts and scholars in countries around the world.

[0003] According to relevant statistics, electric motors currently account for over 60% of my country's total electricity consumption. Electric motors are widely used in industries such as port cranes, petroleum, metallurgy, mining, and transportation. Traditional electric motors have significant drawbacks, including high energy consumption, high failure rates, and low transmission efficiency. Electric vehicles, in particular, rely on onboard power supplies, making high efficiency and energy saving crucial. Reducing electric motor energy consumption can directly improve the driving range of electric vehicles; therefore, there is an urgent need to develop new energy-efficient, high-performance electric motors. Summary of the Invention

[0004] To address the above problems, this invention provides a simple, low-energy-consumption, and high-efficiency switching permanent magnet energy-saving motor, comprising a DC power supply, a drive unit, and a motor, characterized in that: the DC power supply is connected to the motor via the drive unit;

[0005] The speed control of the drive unit adopts a square wave excitation control with a three-phase full-bridge circuit structure, and the torque control adopts thyristor chopper voltage regulation control.

[0006] The motor includes a stator core, pole windings, a rotor core, and a rotor shaft. The stator core includes a stator yoke and stator poles disposed on the inner ring of the stator yoke. Pole windings are wound on each stator pole, and the pole windings are connected to form a phase winding. The rotor core includes a rotor yoke, rotor poles, and permanent magnets. Rotor poles are disposed on the outer ring of the rotor yoke, and rotor slots are formed between adjacent rotor poles. Permanent magnets are embedded in the rotor slots in a manner where adjacent permanent magnets have the same polarity. The magnetized rotor poles are distributed in an NSNS… polarity pattern.

[0007] The rotor pole is composed of a rotor pole boss and two rotor pole oblique arcs on both sides. The radial cross-sectional width of the rotor pole boss is not greater than the radial cross-sectional width of the stator pole. The radial cross-sectional edge of the rotor pole oblique arc is a reverse parabola to highlight the rotor pole boss. The number of stator poles is a multiple of 3, and the number of rotor poles is an even number.

[0008] The torque control unit adjusts the duty cycle of the input pulse to the base of the thyristor by using the torque signal from the torque sensor mounted on the motor and the current and voltage signals fed back from the drive unit, thereby controlling the turn-on and turn-off time of the thyristor and the freewheeling diode to provide a continuously adjustable DC current to the system.

[0009] The speed control unit obtains a continuously adjustable motor rotation speed by controlling the commutation cycle time of the insulated gate bipolar transistor in the drive unit. Attached Figure Description

[0010] Figure 1 This is a radial cross-sectional view of the 12 / 8 motor in an embodiment of the present invention;

[0011] Figure 2 This is a circuit connection block diagram of the present invention;

[0012] Figure 3 This is a diagram showing the connection of the motor stator windings in an embodiment of the present invention;

[0013] Figure 4 This refers to the stator and rotor states when the insulated gate bipolar transistors T1 and T4 are turned on in an embodiment of the present invention.

[0014] Figure 5 This describes the stator and rotor states after the insulated gate bipolar transistors T1 and T4 are turned on in an embodiment of the present invention.

[0015] Figure 6 This refers to the stator and rotor states when the insulated gate bipolar transistors T1 and T6 are turned on in an embodiment of the present invention.

[0016] Figure 7 This describes the stator and rotor states after the insulated gate bipolar transistors T1 and T6 are turned on in an embodiment of the present invention.

[0017] Figure 8 This refers to the stator and rotor states when the insulated gate bipolar transistors T3 and T6 are turned on in an embodiment of the present invention.

[0018] Figure 9 This describes the stator and rotor states after the insulated gate bipolar transistors T3 and T6 are turned on in an embodiment of the present invention.

[0019] Figure 10 This refers to the stator and rotor states when the insulated gate bipolar transistors T2 and T3 are turned on in an embodiment of the present invention.

[0020] Figure 11 This describes the stator and rotor states after the insulated-gate bipolar transistors T2 and T3 are turned on in an embodiment of the present invention.

[0021] Figure 12 This refers to the stator and rotor states when the insulated gate bipolar transistors T2 and T5 are turned on in an embodiment of the present invention.

[0022] Figure 13 This describes the stator and rotor states after the insulated gate bipolar transistors T2 and T5 are turned on in an embodiment of the present invention.

[0023] Figure 14 This refers to the stator and rotor states when the insulated gate bipolar transistors T4 and T5 are turned on in an embodiment of the present invention.

[0024] Figure 15 This represents the stator and rotor states after the insulated gate bipolar transistors T4 and T5 are turned on in an embodiment of the present invention.

[0025] In the diagram: 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 sleeve, 10. Rotor shaft, 11. Permanent magnet, 12. Rotor pole boss, 13. Rotor pole slant, 14. Magnetic detector, C. Zener capacitor, D. Freewheeling diode, D1~D6. Fast recovery diode, T. Thyristor, T1~T6. Insulated gate bipolar transistor, k. Star point electronic switch, k1. Phase A electronic switch, k2. Phase B electronic switch, k3. Phase C electronic switch. Detailed Implementation

[0026] The technical solutions of this application will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "positive," "negative," "vertical," "horizontal," "top," "bottom," "inner," "outer," "one side," "one end," and "one side," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0028] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly; they can refer to mechanical connections or electrical connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0029] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0030] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is 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 the plural forms unless the context clearly indicates otherwise.

[0031] It should also be further understood that the term “and / or” as used in this specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0032] The accompanying drawings illustrate various structural schematics according to embodiments disclosed in this application. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0033] Referring to the accompanying drawings, this application discloses a switchable 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;

[0034] The speed control of the drive unit 2 adopts a square wave excitation control with a three-phase full-bridge circuit structure, and the torque control adopts thyristor T chopper voltage regulation control.

[0035] The motor 3 comprises a stator core 4, magnetic pole windings 7, a rotor core 5, and a rotor shaft 10. The stator core 4 includes a stator yoke and stator magnetic poles 6 arranged on the inner ring of the stator yoke, with magnetic pole windings 7 wound on each stator magnetic pole 6. The rotor core 5 includes a rotor yoke, rotor magnetic poles 8, and permanent magnets 11. Rotor magnetic poles 8 are arranged on the outer ring of the rotor yoke, and rotor slots are formed between adjacent rotor magnetic poles. The permanent magnets 11 are embedded in the rotor slots in such a way that adjacent permanent magnets have the same polarity. The magnetized rotor magnetic poles are distributed in an NSNS… magnetic polarity distribution.

[0036] The rotor pole is composed of rotor pole bosses 12 and rotor pole oblique arcs 13 on both sides. The radial cross-sectional width of the rotor pole bosses 12 is not greater than the radial cross-sectional width of the stator pole 6. The radial cross-sectional edge of the rotor pole oblique arcs 13 is a reverse parabola, highlighting the rotor pole bosses 12. The number of stator poles is a multiple of 3, and the number of rotor poles is an even number.

[0037] 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 by using the torque signal emitted by the torque sensor installed on the motor and the current and voltage signals fed back from the drive unit 2, thereby controlling the turn-on and turn-off time of the thyristor T and the freewheeling diode D to provide the system with a continuously adjustable DC current.

[0038] The speed control unit obtains a continuously adjustable motor rotation speed by controlling the commutation cycle time of the insulated gate bipolar transistor in the drive unit 2.

[0039] A voltage stabilizing capacitor C is also installed on the DC bus of the drive unit 2 to stabilize the DC bus when the AC power supply experiences a momentary power outage or voltage flicker.

[0040] The speed control of the drive unit 2 adopts a square wave excitation control with a three-phase full bridge as the main circuit structure, and the torque control adopts thyristor T chopper voltage regulation control.

[0041] An insulated-gate bipolar transistor (IGBT) T1 is connected in parallel with a reverse-connected fast recovery diode D1 and in series with an IGBT T2. It is also connected to the A-phase winding of motor 3 and via an A-phase electronic switch k1 to the A-phase terminal of the magnetic detector 14. IGBT T2 is connected in parallel with a reverse-connected fast recovery diode D2. Similarly, an IGBT T3 is connected in parallel with a reverse-connected fast recovery diode D3 and in series with an IGBT T4. It is also connected to the B-phase winding of motor 3 and via a B-phase electronic switch k2 to the B-phase terminal of the magnetic detector 14. IGBT T4 is connected in parallel with a reverse-connected fast recovery diode D4. Furthermore, an IGBT T5 is connected in parallel with a reverse-connected fast recovery diode D5 and in series with an IGBT T6. It is also connected to the C-phase winding of motor 3 and via a C-phase electronic switch k3 to the C-phase terminal of the magnetic detector 14. Finally, IGBT T6 is connected in parallel with a reverse-connected fast recovery diode D6.

[0042] The magnetic pole windings 7 are arranged in the order of A, B, C, A, B, C... and every three A, B, C are connected at their tail ends to form a short circuit of the magnetic pole windings. The short circuit tap of any group of magnetic pole windings is led to the star point terminal of the magnetic force detector 14 through the star point electronic switch k.

[0043] Each magnetic pole winding has the same number of 7 turns, the same wire diameter, and the same winding direction, according to... Figure 3 The diagram shows how the magnetic pole windings 7 are connected to form a phase winding.

[0044] Before the motor starts running, the magnetic force detector 14 sends pulse signals to the A, B, and C magnetic pole windings 7 via 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. The magnetic force and polarity of the three-phase windings are compared and detected. The phase stator magnetic pole 6 corresponding to the N-pole rotor magnetic pole is determined by the strongest detected N-pole magnetic force, and this position is set as the initial position.

[0045] When the motor is running, the stator magnetic pole 6, corresponding to the N-pole rotor magnetic pole 8, is not energized and does not establish a magnetic field. The adjacent magnetic pole winding 7 in the rotational direction is energized with a positive current, establishing the same magnetic field as the S-pole rotor magnetic pole 8, generating a repulsive electromagnetic force. Simultaneously, the adjacent magnetic pole winding 7 in the rotational direction is energized with a reverse current, establishing a magnetic field opposite to the S-pole rotor magnetic pole 8, generating an attractive electromagnetic force. The rotor deflects under the influence of the magnetic field, aligning the S-pole rotor magnetic pole 8 with the next stator magnetic pole 6 in the rotational direction. After reaching this position, the stator magnetic pole 6... To prevent the magnetic pole winding 7 corresponding to the S-pole rotor magnetic pole 8 from being energized and establishing a magnetic field, a reverse current is energized in the magnetic pole winding 7 adjacent to the N-pole rotor magnetic pole 8, establishing a magnetic field identical to that of the N-pole rotor magnetic pole 8, generating a repulsive electromagnetic force. Simultaneously, a forward current is energized in the magnetic pole winding 7 adjacent to the N-pole rotor magnetic pole 8, establishing a magnetic field opposite to that of the N-pole rotor magnetic pole 8, generating an attractive electromagnetic force. Under the action of the magnetic field, the rotor deflects and enters the N-pole rotor magnetic pole 8, aligning with the next stator magnetic pole 6 in the direction of rotation. This cycle is repeated to form an electromagnetic torque, converting electrical energy into mechanical energy.

[0046] Referring to the attached diagram, taking a 12 / 8 pole motor as an example: the motor's 3-phase windings are star-connected, and combined with square wave control, a continuous positive torque is generated to ensure that the motor 3 can operate normally. Every 90° is one energizing cycle of the motor, and the phase is commutated every 15°. Three-phase square wave control: this cycle repeats, and each cycle conducts 90° of mechanical angle.

[0047] The initial motor position of 0° is set as the alignment of the C-phase stator magnetic pole 6 and the N-phase rotor magnetic pole 8. When the insulated gate bipolar transistors (IGBTs) T1 and T4 are turned on, the rotor position is 0°→15°, and the motor winding current direction is A→B. When the IGBTs T1 and T6 are turned on, the rotor position is 15°→30°, and the motor winding current direction is A→C. When the IGBTs T3 and T6 are turned on, the rotor position is 30°→45°, and the motor winding current direction is B→C. When the IGBTs T2 and T3 are turned on, the rotor position is 45°→60°, and the motor winding current direction is B→A. When the IGBTs T2 and T5 are turned on, the rotor position is 60°→75°, and the motor winding current direction is C→A. When the IGBTs T4 and T5 are turned on, the rotor position is 75°→90°, and the motor winding current direction is C→B, and the motor rotates in the forward direction.

[0048] The initial motor position of 0° is set to the alignment of the C-phase stator magnetic pole 6 and the N-phase rotor magnetic pole 8. When insulated-gate bipolar transistors T2 and T3 are turned on, the rotor position changes from 0° to -15°, and the motor winding current direction is B to A. When insulated-gate bipolar transistors T3 and T6 are turned on, the rotor position changes from -15° to -30°, and the motor winding current direction is B to C. When insulated-gate bipolar transistors T1 and T6 are turned on, the rotor position changes from -30° to -45°. When the motor winding current direction is A→C; when the insulated gate bipolar transistors T1 and T4 are turned on, the rotor position is -45°→-60°, and the motor winding current direction is A→B; when the insulated gate bipolar transistors T5 and T4 are turned on, the rotor position is -60°→-75°, and the motor winding current direction is C→B; when the insulated gate bipolar transistors T5 and T2 are turned on, the rotor position is -75°→-90°, and the motor winding current direction is C→A, and the motor reverses direction.

[0049] Since the rotor position is not consistent before the motor starts, the following situations may occur:

[0050] In the first case, the N pole of the rotor magnetic pole 8 is aligned with the C pole of the stator magnetic pole 6. The magnetic force detector 14 outputs a pulse test voltage to the magnetic pole winding 7 and measures the degree of resistance of the current passing through the magnetic pole winding 7 to determine the corresponding position of the aligned rotor magnetic pole 8 and the stator magnetic 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. According to the direction requirement, the magnetic pole winding 7 is sequentially turned on with the corresponding current in the set insulated gate bipolar transistor switching sequence.According to the right-hand screw rule and the law of electromagnetic force, the current directions in each magnetic pole winding are as follows: stator magnetic pole A is always S-polarity, stator magnetic pole B is always N-polarity, and stator magnetic pole C is unenergized and has no polarity. Each stator magnetic pole A has the same polarity as each rotor magnetic pole S, generating a repulsive electromagnetic force. Simultaneously, the N-polarity stator magnetic pole B generates an attractive electromagnetic force on the rotor magnetic pole S. Due to the unbalanced structure of the stator and rotor magnetic poles, the rotor rotates in the predetermined direction of the stator magnetic pole current, aligning the S pole of rotor magnetic pole 8 with the B pole of stator magnetic pole 6. Then, the next step involves changing the conduction strategy of the insulated-gate bipolar transistor so that stator magnetic pole A is always S-polarity, stator magnetic pole C is always N-polarity, stator magnetic pole B is unenergized and has no polarity, and each stator magnetic pole C has the same polarity as each rotor magnetic pole N. Both poles of the same polarity generate a repulsive electromagnetic force. Simultaneously, the stator pole A, with its N polarity, generates an attractive electromagnetic force on the rotor pole S. The rotor rotates according to the predetermined direction of the stator pole current, aligning the N pole of rotor pole 8 with the A pole of stator pole 6. The next step involves changing the conduction strategy of the insulated-gate bipolar transistor, making all stator poles B S-polarized and all stator poles C N-polarized. Stator pole A is de-energized and has no polarity. Each stator pole B then interacts with its respective rotor pole. The stator poles S and B, being of the same polarity, generate a repulsive electromagnetic force. Simultaneously, the stator pole C, with its N polarity, generates an attractive electromagnetic force on the rotor pole S. The rotor rotates according to the predetermined direction of the stator pole current, aligning the S pole of rotor pole 8 with the C pole of stator pole 6. The next step involves changing the conduction strategy of the insulated-gate bipolar transistor (IGBT). All stator poles A are N polarity, all stator poles B are S polarity, and stator pole C is unenergized and has no polarity. Each stator pole A is then aligned with the N pole of each rotor pole. When the poles are of the same polarity, they all generate a repulsive electromagnetic force. At the same time, the stator pole B with the S polarity generates an attractive electromagnetic force on the rotor pole S. The rotor rotates in the predetermined direction of the stator pole current, aligning the N pole of the rotor pole 8 with the B pole of the stator pole 6. The next step involves changing the conduction strategy of the insulated gate bipolar transistor (IGBT), so that all stator poles C are S polarity, all stator poles A are N polarity, and stator pole B is unenergized and has no polarity. Each stator pole C has the same polarity as each rotor pole S, generating a repulsive electromagnetic force. At the same time, the stator pole A with the N polarity generates an attractive electromagnetic force on the rotor pole S. The rotor rotates in the predetermined direction of the stator pole current, aligning the N pole of the rotor pole 8 with the C pole of the stator pole 6. This process repeats continuously, and the motor continuously converts electrical energy into mechanical energy to drive the load and perform work.

[0051] In the second scenario, the S pole of rotor magnetic pole 8 aligns with the C pole of stator magnetic pole 6. Magnetic detector 14 outputs a pulse test voltage to the magnetic pole winding 7, measuring the degree of resistance encountered by the current passing through the magnetic pole winding 7 to determine the corresponding position and polarity of the aligned rotor magnetic pole 8 and stator magnetic pole. After confirmation, the star point electronic switch k, A-phase electronic switch k1, B-phase electronic switch k2, and C-phase electronic switch k3 are disconnected. Following the rotation requirements and the set switching sequence of the insulated gate bipolar transistor, the magnetic pole winding 7 is sequentially energized with the corresponding current. In each magnetic pole winding, the stator magnetic pole A is N-polarity, the stator magnetic pole B is S-polarity, and the stator magnetic pole C is unenergized and has no polarity. Each stator magnetic pole A is aligned with each rotor magnetic pole N-polarity. When stator poles of the same polarity are connected, they generate a repulsive electromagnetic force. Simultaneously, the stator pole B with the S polarity generates an attractive electromagnetic force on the rotor pole S. The rotor rotates in the predetermined direction of the stator current, aligning the N pole of rotor pole 8 with the B pole of stator pole 6. The next step involves changing the conduction strategy of the insulated-gate bipolar transistor (IGBT), so that all stator poles C are S polarity, all stator poles A are N polarity, and stator pole B is de-energized and has no polarity. Each stator pole C shares the same polarity with each rotor pole S, generating a repulsive electromagnetic force. Simultaneously, the stator pole A with the N polarity generates an attractive electromagnetic force on the rotor pole S. The rotor rotates in the predetermined direction of the stator current, aligning the N pole of rotor pole 8 with the C pole of stator pole 6. The next step involves changing the conduction strategy of the IGBT, so that all stator poles C are S polarity, all stator poles B are N polarity, and stator poles C are de-energized and have no polarity. Each stator pole A shares the same polarity with each rotor pole S. Both poles of the same polarity generate a repulsive electromagnetic force. Simultaneously, the stator pole B, with its 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 rotates in the predetermined direction of the stator pole current, aligning the S pole of rotor pole 8 with the B pole of stator pole 6. The next step involves changing the conduction strategy of the insulated-gate bipolar transistor so that all stator poles A are S polarity, all stator poles C are N polarity, and stator pole B is unenergized and has no polarity. Each stator pole C then aligns with the N pole of each rotor pole. When two poles are of the same polarity, they all generate a repulsive electromagnetic force. At the same time, the stator pole A, which has an N polarity, generates an attractive electromagnetic force on the rotor pole S. The rotor rotates in the predetermined direction of the stator pole current, aligning the N pole of rotor pole 8 with the A pole of stator pole 6. The next step involves changing the conduction strategy of the insulated-gate bipolar transistor (IGBT), so that all stator poles B are S polarity, all stator poles C are N polarity, and stator pole A is de-energized and has no polarity. Each stator pole B and each rotor pole S has the same polarity, generating a repulsive electromagnetic force. At the same time, the stator pole C, which has an N polarity, generates an attractive electromagnetic force on the rotor pole S. The rotor rotates in the predetermined direction of the stator pole current, aligning the S pole of rotor pole 8 with the C pole of stator pole 6. This process repeats continuously, and the motor continuously converts electrical energy into mechanical energy to drive the load and perform work.

[0052] In the third case, the N pole of the rotor magnetic pole 8 is aligned with the A pole of the stator magnetic pole 6. In the fourth case, the S pole of the rotor magnetic pole 8 is aligned with the A pole of the stator magnetic pole 6. In the fifth case, the N pole of the rotor magnetic pole 8 is aligned with the B pole of the stator magnetic pole 6. In the sixth case, the S pole of the rotor magnetic pole 8 is aligned with the B pole of the stator magnetic pole 6. The operating strategy is the same as that in the first and second cases, and will not be repeated.

[0053] In the seventh scenario, when the N pole of rotor pole 8 is aligned with the C pole of stator pole 6 by at least 50% and is offset in the opposite direction, forward current flows through the C-phase and A-phase pole windings, and reverse current flows through the B-phase pole winding. That is, insulated-gate bipolar transistors T1, T4, and T5 are turned on, making the electromagnetic polarity of stator pole A and stator pole B both S poles. The C pole of stator pole 6 and rotor pole N generate an attractive electromagnetic force, while the A pole of stator pole 6 and rotor pole S generate a repulsive electromagnetic force. The N pole of rotor pole 8 and the C pole of stator pole 6 are completely aligned. Thereafter, the magnetization sequence of the stator poles is repeated according to the above steps.

[0054] In the eighth scenario, when the N pole of rotor pole 8 is aligned with the C pole of stator pole 6 by at least 50% and is positively offset, reverse current flows through the C-phase and B-phase pole windings, while forward current flows through the A-phase pole winding. This means that insulated-gate bipolar transistors T1, T4, and T6 are turned on, making the electromagnetic polarity of stator poles C and B both N. The C pole of stator pole 6 and rotor pole N generate a repulsive electromagnetic force, while the B pole of stator pole 6 and rotor pole S generate an attractive electromagnetic force. The S pole of rotor pole 8 is completely aligned with the B pole of stator pole 6. Thereafter, the magnetization sequence of the stator poles is repeated according to the above steps.

[0055] In the ninth case, when the alignment of the N pole of the rotor magnetic pole 8 with the stator magnetic pole 6 is less than 50%, due to the asymmetry of the number of poles of the rotor and stator, the alignment of the S pole of the rotor magnetic pole 8 with the stator magnetic pole 6 will exceed 50%. The conduction sequence of the insulated gate bipolar transistor is adjusted according to the S pole alignment method as described above.

[0056] When the motor needs to reverse, the current flowing through the magnetic pole winding 7 is the opposite of the above situation.

[0057] 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 decreases, thereby decreasing the winding current of the motor 3. 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.

[0058] A magnetic shielding sleeve 9 is installed between the rotor shaft 10 and the rotor magnetic poles 8 and permanent magnets 11 to prevent magnetic leakage. At both ends of the rotor assembly, pressure plates made of non-magnetic material with a tensile strength of 500-700 MPa and a yield strength of 345-360 MPa are provided.

[0059] This invention application allows for separate control of the motor's speed and torque. During initial operation, the motor operates at high torque and low speed. As inertia increases, the torque output gradually decreases while the operating speed increases, eventually reaching full speed. Furthermore, during low-load operation, the torque output is further reduced without decreasing the operating speed. This invention application also features both low-speed, high-torque and high-speed, low-torque operating modes, offering advantages in energy efficiency and wide applicability in electric vehicles, power transmission, rotating machinery, and other fields.

Claims

1. A switching permanent magnet energy-saving motor, comprising a DC power supply (1), a drive unit (2), and a motor (3), characterized in that: DC power supply (1) is connected to motor (3) via drive unit (2); The speed control of the drive unit (2) adopts a square wave excitation control with a three-phase full-bridge circuit structure, and the torque control adopts a thyristor T-chopper voltage regulation 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) includes a stator yoke and stator magnetic poles (6) arranged on the inner ring of the stator yoke. Magnetic pole windings (7) are wound on each stator magnetic pole (6). The rotor core (5) includes a rotor yoke, rotor magnetic poles (8), and permanent magnets (11). Rotor magnetic poles (8) are arranged on the outer ring of the rotor yoke. Rotor slots are formed between two adjacent rotor magnetic poles. Permanent magnets (11) are embedded in the rotor slots in a manner where adjacent permanent magnets have the same polarity. The magnetized rotor magnetic poles are distributed in an NSNS… magnetic polarity distribution. The rotor pole (8) is composed of rotor pole bosses (12) and rotor pole oblique arcs (13) on both sides. The radial cross-sectional width of the rotor pole bosses (12) is not greater than the radial cross-sectional width of the stator poles (6). The radial cross-sectional edge of the rotor pole oblique arcs (13) is an inverse parabola. The number of stator poles (6) is a multiple of 3, and the number of rotor poles (8) is an even number. The magnetic pole windings (7) are arranged in the order of A, B, C, A, B, C..., and every three A, B, C are connected at the tail end to form a short circuit of the magnetic pole windings. The short circuit tap of any group of magnetic pole windings is led to the star point terminal of the magnetic detector (14) through the star point electronic switch k. Before the motor (3) starts running, the magnetic detector (14) sends pulse signals to the A, B, and C magnetic 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. The magnetic force and polarity of the three-phase windings are compared and detected. The phase magnetic pole winding (7) with the strongest detected N pole magnetic force is determined to be the stator magnetic pole (6) corresponding to the N pole rotor magnetic pole, and this position is set as the initial position. The magnetic detector (14) outputs a pulse test voltage to the magnetic pole winding (7) and measures the degree of resistance of the current passing through the magnetic pole winding (7) to determine the corresponding position of the aligned rotor magnetic pole (8) and the stator magnetic pole, as well as the corresponding polarity. After the determination is completed, the star point electronic switch k, A phase electronic switch k1, B phase electronic switch k2, and C phase electronic switch k3 are disconnected. According to the direction requirement, the magnetic pole winding (7) is turned on with the corresponding current in sequence according to the set insulated gate bipolar transistor switching sequence. When the motor is running, the stator windings corresponding to the N-pole rotor windings are not energized and do not establish a magnetic field. Instead, the windings adjacent to the N-pole rotor windings in the direction of rotation are energized with a forward current, establishing a magnetic field identical to that of the S-pole rotor windings, generating a repulsive electromagnetic force. Simultaneously, the windings energized with the forward current in the adjacent windings in the direction of rotation are energized with a reverse current, establishing a magnetic field opposite to that of the S-pole rotor windings, generating an attractive electromagnetic force. Under the influence of this magnetic field, the rotor deflects, aligning with the next stator winding in the direction of rotation from the S-pole rotor windings. After reaching this position... The stator magnetic poles are not energized in the magnetic pole windings corresponding to the S-pole rotor magnetic poles, and no magnetic field is established. The magnetic pole windings adjacent to the N-pole rotor magnetic poles are energized with reverse current, establishing the same magnetic field as the N-pole rotor magnetic poles, generating a repulsive electromagnetic force. At the same time, the magnetic pole windings energized with reverse current are energized with forward current in the magnetic pole windings adjacent to the N-pole rotor magnetic poles, establishing a magnetic field opposite to the N-pole rotor magnetic poles, generating an attractive electromagnetic force. The rotor deflects under the action of the magnetic field and enters the N-pole rotor magnetic poles and aligns with the next stator magnetic pole in the direction of rotation. This cycle is repeated to form electromagnetic torque. 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 by the torque signal emitted by the torque sensor installed on the motor and the current signal and voltage signal fed back from the drive unit (2), controls the turn-on and turn-off time of the thyristor T, and 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 commutation cycle time of the insulated gate bipolar transistor in the drive unit (2); The drive unit (2) uses a three-phase full-bridge main circuit structure for speed control and a square wave excitation control for torque control.

2. The switching permanent magnet energy-saving motor according to claim 1, 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.

3. The switching permanent magnet energy-saving motor according to claim 1, 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 decreases, thereby decreasing the winding current of the motor (3).

4. The switching permanent magnet energy-saving motor according to claim 1, characterized in that: A magnetic shielding sleeve (9) is installed between the rotor shaft (10) and the rotor magnetic pole (8) and permanent magnet (11) to prevent magnetic leakage. At both ends of the rotor assembly, pressure plates made of non-magnetic material with a tensile strength of 500-700 MPa and a yield strength of 345-360 MPa are provided.

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