A high power density dual-stator interleaved pole hybrid excitation synchronous machine

Abstract

The application discloses a high-power-density double-stator staggered-pole hybrid excitation synchronous motor, wherein permanent magnets one are embedded in the inner surface of a rotor, and permanent magnets two are embedded in the outer surface of the rotor; the permanent magnets one and the permanent magnets two are single polarity, and the number of the permanent magnets one and the permanent magnets two is same as the pole number of control windings, and the number is 2p c ; the polarity of the permanent magnets one and the permanent magnets two on the same side of the rotor is same, and the polarity of the permanent magnets one and the permanent magnets two on the different side of the rotor is opposite; the mechanical angle of the small ferromagnetic magnetic pole between the adjacent two permanent magnets is 180° / p p ; and the axis angle between the adjacent two permanent magnets on the different side is 60°. The application can simultaneously realize the enhancement or weakening of the ferromagnetic magnetic pole on the inner and outer surfaces of the rotor, thereby adjusting the magnetic field intensity of the air gap; the motor has a brushless structure on the rotor side, and the reliability of the motor is high.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a high power density dual-stator staggered magnetic pole hybrid excitation synchronous motor. Background Technology

[0002] Rare-earth permanent magnet motors possess numerous advantages such as fast dynamic response, high power density, and high efficiency, making them widely used in wind power generation, electric vehicles, and other fields. However, their single permanent magnet excitation source makes it difficult to adjust the air gap magnetic field. Electrically excited synchronous motors can adjust the air gap magnetic field strength by changing the excitation current, achieving wide speed range operation. However, the presence of excitation losses results in lower motor efficiency, making it difficult to achieve high power density and high efficiency operation, thus limiting their application.

[0003] To combine the advantages of permanent magnet synchronous motors and electrically excited synchronous motors while overcoming their respective disadvantages, some scholars have proposed a hybrid excitation synchronous motor. In this motor, the permanent magnet generates the main magnetic flux, and the electrical excitation generates the auxiliary magnetic flux. The magnetic flux generated by the permanent magnet is adjusted by increasing and decreasing the magnetization, and the electromagnetic energy conversion is achieved through their interaction.

[0004] Existing hybrid-excitation synchronous motors can be categorized into three types based on the placement of the permanent magnet and excitation winding: those with both permanent magnets and excitation windings located in the rotor or stator, and those with permanent magnets in the rotor and excitation windings in the stator. Motors with both permanent magnets and excitation windings in the rotor require additional devices to achieve brushless operation. The introduction of these additional devices reduces motor reliability and limits further improvements in speed and power density. Motors with both permanent magnets and excitation windings in the stator have a simple structure and high rotor reliability, but their power density and efficiency are relatively low. Motors with permanent magnets in the rotor and excitation windings in the stator offer advantages such as high power density and efficiency, and a wide magnetic adjustment range. Currently, these motors often employ a pole-segmented structure, but they suffer from drawbacks such as complex topology manufacturing processes, high processing difficulty, high manufacturing costs, and low material utilization. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings in the above-mentioned background technology and provide a high-power-density dual-stator staggered magnetic pole hybrid excitation synchronous motor with high reliability and efficiency.

[0006] To achieve the above objectives, this invention proposes a high power density dual-stator staggered pole hybrid excitation synchronous motor, comprising a rotor, an outer stator, and an inner stator, wherein the outer stator has p pole pairs. p The power winding has p pole pairs arranged on the inner stator. c The control winding, wherein a power winding is provided on the outer stator, characterized in that:

[0007] A first permanent magnet is embedded inside the rotor, and a second permanent magnet is embedded outside the rotor. Both the first and second permanent magnets are of single polarity, and their number is the same as the number of pole pairs in the control winding, which is 2p. c ;

[0008] The permanent magnets one and two rotors have the same polarity on the same side and opposite polarity on opposite sides. Furthermore, the mechanical angle between the smaller circumference of the ferromagnetic poles of adjacent permanent magnets is 180° / p. p The included angle between the axes of two adjacent permanent magnets on opposite sides is 60°.

[0009] Furthermore, the number of pole pairs of the power winding and the control winding satisfies p p =3p c The thickness of permanent magnet one and permanent magnet two is the same as the thickness of the rotor.

[0010] Furthermore, the outer stator has two sets of windings, and the inner stator has one set of windings; the number of pole pairs of the two sets of windings of the outer stator satisfies p. p =3p c The inner stator has a set of windings with the same number of pole pairs as the outer stator power windings, both being p. p .

[0011] Furthermore, the rotational speeds at which the magnetic fields are generated by the two sets of windings of the inner and outer stators satisfy the following relationship with the rotor speed:

[0012] 60f p / p p =60f c / p c =n, meaning the frequencies of the control winding and the power winding satisfy f p =3f c .

[0013] Furthermore, the magnetic field formed by the control winding is oriented directly towards the axis of the ferromagnetic pole, and the air gap magnetic field is adjusted by changing the magnitude of the excitation of the control winding; the number of slots in the outer stator and the inner stator may be equal or unequal, and the rotor adopts axial lamination.

[0014] Compared with the prior art, the present invention has the following technical advantages:

[0015] The high-power-density dual-stator staggered-pole hybrid excitation synchronous motor of this invention, compared with existing hybrid excitation synchronous motors, adopts a concentric coaxial arrangement of the two stators. Permanent magnets are staggered on the inner and outer sides of the rotor. There is no magnetic shielding layer inside the rotor. The permanent magnets on the inner or outer sides of the rotor, while inducing the ferromagnetic poles on the same side, can also enhance the corresponding ferromagnetic poles on the opposite side through the rotor core, thereby improving the utilization rate of the permanent magnets. Furthermore, the amount of permanent magnets used is only 1 / 3 of that in traditional permanent magnet motors, resulting in lower motor costs. The internal space of the rotor is effectively utilized, and the axial length is arbitrary. The magnetic field formed by the outer stator control windings is aligned with the axis of the inner and outer ferromagnetic poles of the rotor, allowing for simultaneous enhancement or weakening of the ferromagnetic poles on both sides, thereby adjusting the magnetic field strength in the air gap. There is no brush structure on the rotor side, resulting in higher motor reliability. Attached Figure Description

[0016] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings:

[0017] Figure 1 This invention presents a novel high-power-density dual-stator interleaved magnetic pole hybrid excitation synchronous motor.

[0018] Figure 2 This is a structural diagram of the outer stator of the novel high power density dual-stator interlaced magnetic pole hybrid excitation synchronous motor of the present invention when the number of outer stator slots is 36.

[0019] Figure 3 This is a diagram of the inner stator structure of a novel high-power-density dual-stator interlaced magnetic pole hybrid excitation synchronous motor when the number of inner stator slots is 36.

[0020] Figure 4 This invention provides a rotor structure diagram of a novel high-power-density dual-stator staggered magnetic pole hybrid excitation synchronous motor when the number of permanent magnets on both the inner and outer sides of the rotor is 2.

[0021] Figure 5 The magnetic field distribution of a novel high-power-density dual-stator staggered-pole hybrid excitation synchronous motor at a certain moment when the rotor speed n = 1000 rpm;

[0022] Figure 6 Output voltage waveforms of power windings one and two of the new high power density dual-stator interlaced magnetic pole hybrid excitation synchronous motor at a rotor speed n = 1000 rpm;

[0023] Figure 7 The relationship between the excitation current of the control winding and the output voltage of power winding one and two of the novel high power density dual-stator staggered magnetic pole hybrid excitation synchronous motor when the rotor speed n = 1000 rpm. Detailed Implementation

[0024] To further illustrate the features of the present invention, please refer to the following detailed description and accompanying drawings. The drawings are for reference and illustration only and are not intended to limit the scope of protection of the present invention.

[0025] like Figure 1-7 As shown, this invention discloses a high power density dual-stator interleaved pole hybrid excitation synchronous motor, comprising: an outer stator 7, an inner stator 2, and a rotor 1. Two sets of windings are arranged on the outer stator, one set having p pole pairs. p The power winding has 8 pole pairs, with a total of p pole pairs. c The control winding 4; a power winding 2 3 with the same number of pole pairs as the outer stator is arranged on the inner stator, and the frequency of the current flowing through the power winding 1 8 and the power winding 2 3 is f. p The frequency of the current flowing through the control winding 4 is f. c .

[0026] Two p are arranged on both the inner and outer sides of the rotor. c Two single-polarity permanent magnets, 5 and 6, have a rotor speed of n, and the two sets of outer stator windings have a pole pair number satisfying p. p =3p c The inner stator has one set of windings with the same number of pole pairs as the outer stator power windings, both being p. p The permanent magnets on the same side of the rotor have the same polarity, while those on opposite sides have opposite polarities; the rotational speeds at which the magnetic fields are generated by the control winding and power windings one and two satisfy a 60° interval with the rotor speed. p / p p =60f c / p c =n, meaning the frequencies of the control winding and power winding one / two satisfy f p =3f c .

[0027] In this embodiment, a stator control winding with p pole pairs is selected. c =1, the number of pole pairs of power windings one and two is p p =3, in this embodiment, the number of external stator slots is selected as 36, and its structure is as follows: Figure 2 As shown, the number of internal stator slots is 36, and its structure is as follows: Figure 3 As shown. Two permanent magnets are selected for the inner and outer sides of the rotor. These permanent magnets are magnetized in parallel and embedded on the inner and outer surfaces of the rotor. The mechanical angle between permanent magnets on opposite sides of the rotor is 60°. The mechanical angle between the smaller ferromagnetic poles of two adjacent permanent magnets on the same side is 180° / p. p The rotor permanent magnets are distributed as follows Figure 4 As shown.

[0028] In this embodiment, the initial position of the magnetic field direction of the outer stator control winding is directly opposite the axis of the inner and outer ferromagnetic poles of the rotor. When the rotor speed is n = 1000 rpm, in order to keep the direction of the magnetic field of the control winding 4 constant with the axis of the inner and outer ferromagnetic poles of the rotor, the frequency of the control winding 4 must satisfy f c =np1 / 60 = 50 / 3Hz, the output frequency of power windings one and two is f p =np p / 60=50Hz, meaning the rotational speed at which the magnetic field is generated by the control winding and power winding one / two satisfies 60f / Hz with the rotor speed. p / p p =60f c / p c =n. When the effective value of the excitation current of the motor control winding is 6A, and the motor is operating in the magnetization state, the magnetic field line distribution at a certain moment is as follows: Figure 5 As shown, Figure 6 The output voltage waveforms of power windings one and two when connected to different external loads are shown in the figure. It can be seen from the figure that the output voltage waveforms of power windings one and two have good positive linearity and the frequency is 50Hz, which verifies the correctness of the above theory. Figure 7 The relationship between the excitation current of the control winding and the output voltage of power winding one and two of the high power density dual-stator staggered magnetic pole hybrid excitation synchronous motor is given when the rotor speed n = 1000 rpm. As can be seen from the figure, the output voltage of power winding one and two increases with the increase of excitation current, indicating that the motor has good voltage regulation performance.

[0029] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high power density dual-stator staggered pole hybrid excitation synchronous motor, comprising a rotor, an outer stator, and an inner stator, wherein the outer stator has a number of pole pairs arranged thereon. The power winding has a number of pole pairs arranged on the outer stator. The control winding, wherein the number of pole pairs of the power winding and the control winding satisfies The inner stator is provided with a set of power windings, characterized in that: A first permanent magnet is embedded inside the rotor, and a second permanent magnet is embedded outside the rotor. Both the first and second permanent magnets are of single polarity, and their number is the same as the number of pole pairs in the control winding. ; The first permanent magnet has the same polarity, and the second permanent magnet has the same polarity. The polarities of the first and second permanent magnets are opposite, forming a sequential arrangement of first permanent magnet, second ferromagnetic pole, third permanent magnet, fourth permanent magnet, and fifth permanent magnet along the rotor circumference. The first and second ferromagnetic poles do not have permanent magnets, and their circumferential mechanical angles are all... The included angle between the axes of the two adjacent permanent magnets in the circumferential direction is 60°.

2. The high power density dual-stator interleaved magnetic pole hybrid excitation synchronous motor according to claim 1, characterized in that, The outer stator has two sets of windings, and the inner stator has one set of windings; the number of pole pairs of the two sets of windings of the outer stator satisfies the following condition. The inner stator has a set of windings with the same number of pole pairs as the outer stator power windings. .

3. The high power density dual-stator interleaved magnetic pole hybrid excitation synchronous motor according to claim 1, characterized in that, The rotational speed at which the magnetic field is generated by the two sets of windings of the inner and outer stators satisfies the following relationship with the rotor speed: ， That is, the frequencies of the control winding and the power winding satisfy... .

4. The high power density dual-stator interleaved magnetic pole hybrid excitation synchronous motor according to claim 1, characterized in that, The magnetic field formed by the control winding is oriented directly towards the axis of the ferromagnetic pole, and the air gap magnetic field is adjusted by changing the magnitude of the excitation of the control winding.

5. The high power density dual-stator staggered magnetic pole hybrid excitation synchronous motor according to claim 1, characterized in that, The number of slots in the outer stator may be equal to or unequal to the number of slots in the inner stator, and the rotor uses axial lamination.

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