A stator partitioned direct current bias type hybrid excitation motor based on U-shaped permanent magnet

Abstract

This application discloses a stator-partitioned DC-biased hybrid excitation motor based on U-shaped permanent magnets, which can be widely used in the field of motor technology. By partitioning the outer and inner stators, this application ensures a reasonable spatial distribution of permanent magnets and armature windings, eliminating spatial conflicts between the armature windings and permanent magnets, and effectively improving the motor's torque density and operating efficiency. Simultaneously, the use of a U-shaped inner stator permanent magnet and a multi-excitation source hybrid excitation structure with DC components allows for flexible adjustment of the motor's air gap magnetic field, thereby effectively improving the motor's torque density and magnetic field regulation capability, and expanding the motor's speed range. Furthermore, the U-shaped stator permanent magnet structure enables magnetization and reduces magnetic leakage, effectively improving the motor's magnetic field regulation capability and torque density.

Description

Technical Field

[0001] This application relates to the field of motor technology, and in particular to a stator partitioned DC bias hybrid excitation motor based on U-shaped permanent magnets. Background Technology

[0002] In related technologies, with the continuous development of new energy vehicles, wind power generation, and servo drive fields, the requirements for drive systems have also been placed on low-speed high torque and wide speed range. Permanent magnet vernier motors, based on the principle of magnetic field modulation, possess inherent characteristics of low speed and high torque, making them one of the most promising options in the field of high torque density motors. However, traditional permanent magnet vernier motors, due to their single permanent magnet excitation source and fixed magnetic field, are difficult to adjust, limiting the expansion of the motor's speed range. Permanent magnet vernier motors using a hybrid excitation system of DC windings and permanent magnets can effectively broaden the motor's speed range; however, hybrid excitation permanent magnet vernier motors using armature windings to achieve AC / DC multiplexing have relatively low torque density due to the presence of only rotor permanent magnets. Furthermore, stator-rotor dual permanent magnet vernier motors based on DC bias current suffer from spatial conflicts between the stator permanent magnets and stator armature windings, which can affect the motor's operating efficiency.

[0003] In summary, the technical problems existing in the relevant technologies need to be improved. Summary of the Invention

[0004] The main objective of this application is to propose a stator partitioned DC bias hybrid excitation motor based on U-shaped permanent magnets, which can effectively improve the motor's torque density, operating efficiency, and magnetic field regulation capability.

[0005] To achieve the above objectives, this application proposes a stator-partitioned DC biased hybrid excitation motor based on a U-shaped permanent magnet, wherein the hybrid excitation motor includes an outer stator, an intermediate rotor, and an inner stator; An intermediate rotor is placed between the outer stator and the inner stator; There is an external air gap between the outer stator and the intermediate rotor, and there is an internal air gap between the intermediate rotor and the inner stator; The outer stator includes an armature winding and an outer stator core; the outer stator core is provided with an outer stator slot and stator teeth, and the outer stator slot is surrounded by the slot walls of adjacent stator teeth; the coil of the armature winding is wound on the stator teeth; the current input to the armature winding is obtained by combining a three-phase symmetrical AC component and a DC component in the same direction; The inner stator includes an inner stator core and a U-shaped inner stator permanent magnet. The inner stator core is provided with an inner stator slot, into which the U-shaped inner stator permanent magnet is inserted. The U-shaped inner stator permanent magnet includes a spoke-type permanent magnet and an alternating pole permanent magnet. Two adjacent spoke-type permanent magnets form a group, and the magnetic field lines of the spoke-type permanent magnets in the same group are in opposite directions. The magnetic field lines of the alternating pole permanent magnets are all oriented towards the outer stator. The intermediate rotor includes several rotor modulation magnetic blocks, which are used to modulate the electrically excited magnetic field generated on the outer stator or the permanent magnetic field generated by the spoke-type permanent magnet in the inner stator to obtain the target magnetic field component.

[0006] In some embodiments, the armature winding employs a non-overlapping concentrated winding based on a single-layer winding.

[0007] In some embodiments, the armature winding is a three-phase concentrated winding with a neutral point star connection.

[0008] In some embodiments, the intermediate rotor includes 11 rotor modulation magnetic blocks, each of which has a circular hole for fixing the rotor modulation magnetic block.

[0009] In some embodiments, the rotor modulation magnetic block is composed of silicon steel sheets.

[0010] In some embodiments, both the outer stator core and the inner stator core are composed of silicon steel sheets.

[0011] In some embodiments, the inner stator core is a salient polarity core.

[0012] In some embodiments, the U-shaped inner stator permanent magnet is composed of aluminum-iron-boron permanent magnets.

[0013] In some embodiments, the number of pole pairs of the armature winding P s The number of pole pairs of the intermediate rotor P r and the number of pole pairs of the U-shaped inner stator permanent magnet P is The following relationship must be satisfied: .

[0014] In some embodiments, the current input to the armature winding is output by a motor drive control system, which includes dual inverters.

[0015] The embodiments of this application include at least the following beneficial effects: This application provides a stator-partitioned DC biased hybrid excitation motor based on U-shaped permanent magnets. This scheme, by partitioning the outer stator and inner stator, can ensure that the permanent magnets and armature windings can be reasonably allocated in space, eliminating the conflict between the armature windings and permanent magnets in spatial installation, and effectively improving the torque density and operating efficiency of the motor; at the same time, by adopting a hybrid excitation structure of U-shaped inner stator permanent magnets and DC component multi-excitation sources, the air gap magnetic field of the motor can be flexibly adjusted, thereby effectively improving the torque density and magnetic field regulation capability of the motor and expanding the speed range of the motor; and the use of U-shaped stator permanent magnet structure can achieve magnetization and reduce magnetic leakage, effectively improving the magnetic field regulation capability and torque density of the motor. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a stator partitioned DC bias hybrid excitation motor based on a U-shaped permanent magnet according to an embodiment of this application; Figure 2 This is an application schematic diagram of a stator partitioned DC bias hybrid excitation motor based on a U-shaped permanent magnet according to an embodiment of this application; Figure 3 This is a planar schematic diagram of the outer stator provided in an embodiment of this application; Figure 4 This is a planar schematic diagram of the intermediate rotor provided in an embodiment of this application; Figure 5 This is a planar schematic diagram of the inner stator provided in an embodiment of this application; Figure 6 This is a plan view of the stator permanent magnet sub-motor provided in an embodiment of this application; Figure 7 This is a plan view of the DC biased sub-motor provided in the embodiments of this application. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0018] It is understood that the terms “first,” “second,” etc., used in this application may be used to describe various concepts herein, but unless otherwise stated, these concepts are not limited by these terms. These terms are used only to distinguish one concept from another.

[0019] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0021] Before providing a detailed description of the embodiments of this application, some of the nouns and terms used in the embodiments of this application will be explained first. The nouns and terms used in the embodiments of this application shall be interpreted as follows: The spoke-type permanent magnet is the core magnetic pole arrangement of the spoke-type permanent magnet synchronous motor (STPMSM), which is mainly used in scenarios requiring high torque density, such as coal mine tunneling robots and industrial equipment.

[0022] PWM (Pulse Width Modulation) is a technique that uses digital signals to control analog circuits, adjusting the pulse width to generate the desired waveform (such as a sine wave or a signal of a specific amplitude).

[0023] Among related technologies, permanent magnet vernier motors, based on the principle of magnetic field modulation, possess the inherent characteristics of low speed and high torque, making them one of the most promising options in the field of high torque density motors. However, traditional permanent magnet vernier motors, due to their single permanent magnet excitation source and fixed magnetic field, are difficult to adjust, limiting the expansion of the motor's speed range. Permanent magnet vernier motors employing hybrid excitation of DC windings and permanent magnets can effectively broaden the motor's speed range; however, hybrid excitation permanent magnet vernier motors using armature windings to achieve AC / DC multiplexing have relatively low torque density due to the presence of only rotor permanent magnets. Furthermore, dual permanent magnet vernier motors based on DC bias current suffer from spatial conflicts between the stator permanent magnets and stator armature windings, which negatively impact motor operating efficiency.

[0024] In view of this, this application provides a stator partitioned DC bias hybrid excitation motor based on U-shaped permanent magnets, which can effectively improve the motor's torque density, operating efficiency and magnetic field regulation capability.

[0025] The embodiments of this application will be described in detail below with reference to the accompanying drawings: Reference Figure 1 This application provides a stator partitioned DC bias hybrid excitation motor based on U-shaped permanent magnets. The hybrid excitation motor includes an outer stator 110, an intermediate rotor 120, and an inner stator 130; the intermediate rotor 120 is placed between the outer stator 110 and the inner stator 130; there is an outer air gap 140 between the outer stator 110 and the intermediate rotor 120, and an inner air gap 150 between the intermediate rotor 120 and the inner stator 130; the outer stator 110 includes an armature winding 111 and an outer stator core 112; the outer stator core 112 is provided with outer stator slots 113 and stator teeth, and the outer stator slots 113 are surrounded by the slot walls of adjacent stator teeth; the coils of the armature winding 111 are wound on the stator teeth; the current input to the armature winding is obtained by combining the three-phase symmetrical AC component and the DC component in the same direction, and finally forms a loop through the neutral line of the neutral point of the three-phase winding; the inner stator 130 includes an inner stator core 131 and an inner stator core 132. The U-shaped inner stator permanent magnet 132 has an inner stator iron slot on the inner stator core 131 into which the inner stator permanent magnet 132 is inserted. The U-shaped inner stator permanent magnet 132 includes a spoke-type permanent magnet 1321 and an alternating pole permanent magnet 1322. Two adjacent spoke-type permanent magnets 1321 form a group. The magnetic field lines of the spoke-type permanent magnets 1321 in the same group are opposite in direction. For example, the magnetic field lines of the spoke-type permanent magnets in the same group are to the left or right, while the magnetic field lines of the alternating pole permanent magnets 1322 are all towards the outer stator. The intermediate rotor 120 includes several rotor modulation magnetic guide blocks 121. The rotor modulation magnetic guide blocks 121 are used to modulate the electric excitation magnetic field generated on the outer stator or the permanent magnet magnetic field generated by the spoke-type permanent magnets in the inner stator to obtain the target magnetic field component.

[0026] Understandably, the armature winding adopts a non-overlapping concentrated winding based on a single-layer winding, thereby enabling the reuse of the magnetic winding and the armature winding.

[0027] like Figure 1 As shown, a single-layer armature winding is placed in the outer stator slot. This single-layer armature winding is a three-phase concentrated winding with a neutral point star connection, that is, a shared winding for three-phase symmetrical AC and DC. Therefore, the control circuit of this embodiment can adopt a three-phase four-wire inverter circuit with a neutral point, and use I... d =0 is used for control.

[0028] It is understandable that, such as Figure 3As shown, the outer stator core has 12 outer stator slots and 12 stator teeth. The armature winding is a three-phase symmetrical winding with one pole pair, consisting of six coils wound on the six stator teeth. Each phase has two coils connected in series, forming a star connection including the neutral wire. Simultaneously, the armature winding is also a current bias winding, comprising six coils, thus generating a DC excitation magnetic field with six pole pairs.

[0029] It is understandable that, such as Figure 4 As shown, the intermediate rotor includes 11 rotor modulation magnetic blocks, each with a circular hole for fixing it in place. Specifically, each rotor modulation magnetic block is composed of silicon steel sheets.

[0030] It is understandable that, such as Figure 1 and Figure 5 As shown, the inner stator includes an inner stator core and a U-shaped inner stator permanent magnet. The U-shaped inner stator permanent magnet is composed of two types of magnets: spoke-type permanent magnets and alternating pole permanent magnets. The U-shaped inner stator permanent magnet forms a permanent magnetic field with 6 pole pairs, primarily provided by the spoke-type permanent magnets. This magnetic field exhibits high air gap magnetic flux density, high material utilization, and a good magnetic circuit path. Specifically, the inner stator core is a salient-polarity core, and both the inner and outer stator cores are composed of silicon steel sheets. The U-shaped inner stator permanent magnet is composed of aluminum-iron-boron permanent magnets.

[0031] Understandable, Figure 1 The working principle of the motor shown is based on the magnetic field modulation effect; therefore, in this embodiment, the number of pole pairs of the armature winding is... P s Number of pole pairs of the intermediate rotor P r and the number of pole pairs of the U-shaped inner stator permanent magnet P is The following relationship must be satisfied: .

[0032] It is understandable that, such as Figure 2 As shown, the armature winding input current is output by the motor drive control system, which includes dual inverters, thus allowing the input of DC bias current without the need for additional excitation current. Specifically, taking... Figure 2 Taking the application scenario shown as an example, the current flowing into the armature winding is a combination of the three-phase symmetrical AC component and the DC bias current component in the same direction. Finally, the DC bias current in the three-phase winding forms a loop through the neutral line of the neutral point, and its expression is as follows: ; In the formula, I ac The effective value of the AC component.I dc The amplitude of the DC component. The rotor electrical angle is given.

[0033] Specifically, Figure 2 The DC bias current generated in the scenario shown can form a DC magnetic field with 6 pole pairs.

[0034] Understandable, Figure 1 The motor shown can be equivalent to an organic combination of two motors, namely... Figure 6 The stator permanent magnet sub-motor shown and Figure 7 The DC-biased sub-motor shown is an example. Among them, The excitation source of the stator permanent magnet sub-motor is a U-shaped inner stator permanent magnet. This U-shaped inner stator permanent magnet generates a 6-pole excitation magnetomotive force (MOMF), which, after being modulated by the magnetic field of 11 rotor magnetic blocks, forms a 1-pole air gap magnetic field with the same number of pole pairs as the armature winding, thus generating a stable output torque. The excitation source of the DC bias sub-motor is a DC bias current component. This DC bias current generates a 6-pole DC excitation MOMF, which, after being modulated by the magnetic field of 11 rotor magnetic blocks, forms a 1-pole air gap magnetic field with the same number of pole pairs as the armature winding, thus generating a stable output torque. Therefore, Figure 1 The electromagnetic torque of the motor shown is a nonlinear superposition of the output electromagnetic torques of the two sub-motors, which can effectively improve the torque density of the motor. At the same time, by changing the DC bias current component of the DC biased sub-motor, the output electromagnetic torque of the DC biased sub-motor can be effectively changed. Therefore, this embodiment can effectively improve the magnetic field regulation capability of the motor and broaden the speed regulation range of the motor.

[0035] In summary, the electrodes in this embodiment employ a stator partitioning structure to ensure a reasonable spatial distribution of permanent magnets and armature windings, eliminating spatial conflicts between the armature windings and permanent magnets, and effectively improving the motor's torque density and efficiency. By adopting a DC-biased winding structure, the AC armature winding and DC winding are reused, avoiding the need for additional DC windings and effectively reducing the motor's size and cost. Adjusting the DC bias current allows for flexible adjustment of the motor's electrical and magnetic load distribution, thereby improving the motor's torque density, power factor, and efficiency. The use of a U-shaped inner stator permanent magnet and a multi-excitation source hybrid excitation structure with DC components allows for flexible adjustment of the motor's air gap magnetic field, effectively improving the motor's torque density and magnetic field regulation capability, and expanding the motor's speed range. Simultaneously, the U-shaped stator permanent magnet structure enables magnetization and reduces leakage flux, effectively improving the motor's magnetic field regulation capability and torque density.

[0036] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0037] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0038] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0039] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0040] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0041] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0042] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0043] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0044] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A U-shape permanent magnet based stator partitioned DC bias type hybrid excitation machine, characterized in that, The hybrid excitation motor comprises an outer stator, an intermediate rotor and an inner stator; The intermediate rotor is arranged between the outer stator and the inner stator; The outer stator and the intermediate rotor have an outer air gap, and the intermediate rotor and the inner stator have an inner air gap; The outer stator comprises an armature winding and an outer stator core; the outer stator core is provided with outer stator slots and stator teeth, the outer stator slots are surrounded by slot walls of adjacent stator teeth; the coils of the armature winding are wound on the stator teeth; the current input by the armature winding is composed of three-phase symmetrical alternating current components and direct current components with the same direction; The inner stator comprises an inner stator core and U-shaped inner stator permanent magnets, the inner stator core is provided with inner stator slots, and the inner stator slots are inserted into the U-shaped inner stator permanent magnets; the U-shaped inner stator permanent magnets comprise spoke-type permanent magnets and alternating pole-type permanent magnets, two adjacent spoke-type permanent magnets form a group, the magnetic force lines of the spoke-type permanent magnets in the same group are opposite, and the magnetic force lines of the alternating pole-type permanent magnets all point to the outer stator; The intermediate rotor comprises a plurality of rotor modulation flux guiding blocks, which are used to modulate the electric excitation magnetic field generated on the outer stator or the permanent magnetic field generated by the spoke-type permanent magnets in the inner stator to obtain a target magnetic field component.

2. The hybrid excitation electric machine according to claim 1, characterized in that The armature winding adopts a non-overlapping concentrated winding based on a single-layer winding.

3. The hybrid excitation electric machine according to claim 1, characterized in that, The armature winding is a three-phase concentrated winding comprising a neutral point star connection.

4. The hybrid excitation machine of claim 1, wherein The intermediate rotor comprises 11 rotor modulation flux guiding blocks, each of which is provided with a circular hole for fixing the rotor modulation flux guiding block.

5. The hybrid excitation machine of claim 4, characterized in that The rotor modulation flux guiding blocks are composed of silicon steel sheets.

6. The hybrid excitation machine of claim 1, wherein The outer stator core and the inner stator core are both composed of silicon steel sheets.

7. The hybrid excitation machine of claim 6, characterized in that The inner stator core is a salient pole core.

8. The hybrid excitation machine of claim 1, wherein, The U-shaped inner stator permanent magnets are composed of aluminum-iron-boron permanent magnets.

9. The hybrid excitation machine of claim 3, wherein, a number of pole pairs of the armature winding P s a number of pole pairs of the intermediate rotor P r and a number of pole pairs of the U-shaped inner stator permanent magnet P is satisfies the following relation: 。 10. The hybrid excitation machine of claim 1, wherein, The current input by the armature winding is output by a motor drive control system, and the motor drive control system comprises a double inverter.

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