CN203289210U - A mixed excitation-type stator surface mounting-type double-salient-pole motor - Google Patents

Abstract

A mixed-excitation stator surface-mounted double salient pole motor with a modular rotor. On the one hand, the stator part adopts a centralized armature winding and a centralized excitation winding. The stator teeth are divided into two groups, which are respectively attached with permanent magnets The stator teeth and the stator teeth covered with armature winding coils, and the armature teeth and permanent magnet teeth are alternately distributed. The radially alternately magnetized permanent magnets are respectively attached to the surface of a stator permanent magnet tooth facing the rotor. Each coil of the armature winding is respectively sleeved on a stator armature tooth, and each coil of the centralized excitation winding is respectively sleeved on a stator permanent magnet tooth. The utility model retains the advantages of the stator surface-mounted double-salient pole permanent magnet motor in terms of structure, such as compact structure and easy heat dissipation, and can realize the mixed excitation function without additionally increasing the volume of the motor, ensuring that the motor has a strong torque output capability and relatively High power density, especially suitable for applications that require small size and high output, and can realize large torque in the constant torque area and wide speed regulation in the constant power area.

Description

A Mixed Excitation Stator Surface Mount Type Double Salient Pole Motor

technical field

The utility model relates to a double-salient pole brushless motor with armature coil turn chain and bipolar permanent magnet flux chain, which has high utilization rate of permanent magnet and adopts modular rotor, especially a motor with mixed excitation function, which belongs to the motor The technical field of manufacture. the

Background technique

With the intensification of the energy crisis, it has become the consensus of the world to use permanent magnet excitation instead of electric excitation to save energy consumption. At the same time, since my country is the country with the richest rare earth resources in the world, it is necessary to develop, research and promote the application of new structure rare earth permanent magnets. Motor has important theoretical significance and practical value. Especially for hybrid electric vehicles, which are widely studied at present, the motor drive system is required to be small in size, light in weight, high in efficiency, strong in reliability, free of maintenance, large in torque output, and wide in speed regulation range. However, the permanent magnet motor itself has the bottleneck that the air gap magnetic field cannot be adjusted, which limits its application in hybrid electric vehicles. The vast majority of permanent magnet motor no-load permanent magnet flux linkage is greater than the product of direct axis inductance and rated current, the maximum torque of permanent magnet motor in the constant torque region and the maximum operating speed in the constant power region are a pair that cannot Reconcile the contradiction: on the one hand, increasing the permanent magnet flux linkage can certainly improve the maximum torque output capability of the motor, but at the same time limit the high-speed operation of the motor (due to the increasing no-load back electromotive force); on the other hand, when the inverter When the current limit of the motor and the direct axis inductance of the motor are fixed, reducing the permanent magnet flux linkage is beneficial to improve the constant power operating range of the motor but will limit the torque output. Therefore, the above-mentioned shortcoming of the permanent magnet motor has become a bottleneck restricting its application and popularization. Most of the current hybrid excitation motors based on rotor permanent magnet motors place the DC excitation winding on the stator. In order to provide a path parallel to the permanent magnet flux in the radial or axial direction for the electric excitation flux, the proposed motor structure is very complicated, and it faces huge challenges in terms of manufacturing process and mass production of finished products. challenge. If a hybrid excitation motor needs to make a significant sacrifice in terms of structural complexity in order to achieve magnetic field adjustment, its competitiveness will be greatly reduced.

On the other hand, in the 1990s, three types of stator permanent magnet motors with new structures appeared successively in the world, namely flux pulsating permanent magnet motors, flux switching permanent magnet motors and flux reversing permanent magnet motors. The common feature is that both the permanent magnet and the armature winding are placed in the stator, and the rotor is only composed of soft magnetic materials such as silicon steel sheets. Among them, the structural principle of the flux reversal motor is to install two permanent magnets with opposite polarities side by side on each salient pole stator tooth. The purpose is to obtain a bipolar permanent magnet flux linkage, but this structure directly leads to two The magnetic steel and the stator teeth form a short circuit, and the magnetic flux leakage is serious, which reduces the utilization rate of the unit magnetic steel. In the traditional stator surface-mounted motor, the armature flux chain changes in unipolarity, which reduces the utilization rate of the permanent magnet. The utility model is based on the structure of the stator surface-mounted permanent magnet motor. A hybrid excitation stator surface mount brushless motor with a modular rotor, trying to achieve the hybrid excitation function without major modifications on the basis of maintaining a pure permanent magnet motor.

Contents of the invention

The purpose of this utility model is to propose a hybrid excitation stator surface-mounted double-salient pole brushless motor with a modular rotor, which can reasonably arrange the space of the electric excitation winding without additionally increasing the volume of the original pure permanent magnet motor Under certain conditions, the power density of the motor can be further improved, and at the same time, various performances can be improved in all aspects through flexible adjustment of the electric excitation current and armature current, including maximum torque, constant power maximum operating speed and high efficiency in the entire operating range.

The technical scheme that the utility model adopts is:

A hybrid excitation stator surface-mounted double salient pole motor with a modular rotor, the motor includes: a stator, a concentrated armature winding, a rotor core, a permanent magnet, a single-phase concentrated excitation winding and a magnetic isolation mechanism; its characteristics In that: both the stator core and the rotor core are of salient pole structure; the stator teeth are divided into two groups, namely permanent magnet teeth attached with permanent magnets and armature teeth covered with armature winding coils, and the armature teeth Alternately distributed with the permanent magnet teeth; the coils of the concentrated armature winding are respectively sleeved on a stator armature tooth; the permanent magnets are respectively mounted on the surface of a stator permanent magnet tooth facing the rotor, and each permanent magnet is radial Magnetization, and the magnetization directions of two adjacent permanent magnets are opposite; each coil of the concentrated excitation winding is respectively sleeved on a stator excitation tooth, and each excitation coil is connected in series to form a single-phase excitation winding; the rotor consists of a U-shaped The magnetically permeable rotor core and the magnetically isolated mechanism are composed, and each U-shaped magnetically permeable rotor core is respectively embedded in the magnetically isolated mechanism; the U-shaped magnetically permeable core units of the rotor can be connected together through the connecting bridge, because the internal magnetic field of the connecting bridge High saturation, large magnetic resistance, can effectively prevent magnetic flux leakage.

Both the stator core and the rotor core are salient pole structures, the stator includes a stator core, a centralized armature winding, permanent magnets and a concentrated field winding, and the rotor includes a U-shaped rotor core and a magnetic isolation mechanism .

The direction of the current flowing into the excitation winding is different, and the direction of the electric excitation flux is the same as or opposite to that of the permanent magnet flux. The direction of the permanent magnetic flux generated by the permanent magnet mounted on the lower part is the same, and the electric excitation reaches the magnetization effect; The direction of the permanent magnetic flux generated by the mounted permanent magnet is opposite, and the electric excitation to demagnetization effect.

The armature winding coils that make up one phase have winding complementarity, and the armature induced potential is a sine wave or a square wave.

According to the specific cogging of the stator and rotor, each coil of the centralized armature winding can be connected into a single-phase or multi-phase armature winding; the centralized armature winding can be in the form of a distributed winding.

Each of the permanent magnets is radially magnetized, and the magnetization directions of two adjacent permanent magnets are opposite; the permanent magnets are ferrite or NdFeB permanent magnet materials.

The rotor cores can be connected as a whole through connecting bridges.

The rotor core and magnetic isolation mechanism are located outside the stator, forming an outer rotor structure.

The materials of the stator core, the rotor core and the connecting bridge are all magnetically permeable materials of silicon steel sheets.

The material of the magnetic isolation mechanism is non-magnetic material such as copper and aluminum.

The electrical machine can be operated as a generator or as an electric motor.

On the other hand, due to the characteristics of the double salient pole structure of the motor stator and rotor, the hybrid excitation stator surface mount brushless motor can easily obtain the permanent magnet flux linkage very close to the trapezoidal wave or sine wave, no-load In addition, a more sinusoidal counter electromotive force can be obtained through a certain angle of the rotor chute, so that the utility model is suitable as an AC speed regulation system component in a brushless AC drive mode.

In addition, the characteristics of the structure of the motor lead to a large no-load air gap flux density, and the motor has a strong torque output capability and a high power density; at the same time, the armature winding and the field winding are concentrated windings, and the end Short, small resistance, high efficiency.

The beneficial effects obtained by the technical solution of the utility model;

1. In the motor of the present utility model, the centralized armature winding, the centralized excitation winding and the permanent magnet are all located on the stator side, which is beneficial to improve the cooling conditions during the operation of the motor and facilitate the heat dissipation of the motor;

2. The motor of this utility model retains the characteristic that the stator and rotor of the traditional double-salient motor are salient pole structures, and can easily obtain the induced potential waveform of each phase winding close to a square wave or a sine wave through the cooperation of different stator and rotor slots. The control method is more flexible, adapting to different AC speed regulation and servo drive occasions;

3. A set of electric excitation windings added to the motor of the utility model can be placed without increasing the volume of the motor;

4. In the double-salient pole permanent magnet motor with magnetic flux reversal, two permanent magnets with opposite magnetization directions are pasted under each stator tooth, and the magnetic flux leakage between the permanent magnets is relatively serious. However, in the motor of the utility model, each stator permanent magnet Only one permanent magnet is pasted on the magnetic tooth, which significantly weakens the magnetic flux leakage of the permanent magnet and improves the utilization rate of the permanent magnet;

5. Compared with the traditional stator surface-mounted double salient pole permanent magnet motor, the motor of this invention adopts a modular rotor, and only half of the stator teeth are attached with permanent magnets, and the permanent magnets of each coil of the armature winding are The magnetic flux is bipolar, which has a high utilization rate of permanent magnets;

6. Since the armature and excitation windings of the motor of the utility model both adopt centralized windings, the ends of the windings are relatively short, which is beneficial to improving the efficiency of the motor and reducing the manufacturing cost. the

Description of drawings

Fig. 1 is a transverse sectional view of the motor of the present invention.

Fig. 2 is a transverse cross-sectional view of the motor of the present invention with a connecting bridge added.

Fig. 3 is the working principle diagram of the motor of the present utility model;

Fig. 4 is the single-turn flux linkage waveform diagram of the A-phase armature winding of the motor of the present invention under different excitation conditions;

Fig. 5 is the waveform diagram of the single-turn induced potential of the A-phase armature winding of the motor of the present invention under different excitation conditions;

Reference signs: 1 - stator core, 2 - concentrated armature winding, 3 - rotor core, 4 - permanent magnet, 5 - concentrated excitation winding, 6 - magnetic isolation mechanism, 7 - connecting bridge.

Detailed ways

The utility model will be described below with reference to the accompanying drawings.

As shown in Figure 1, the utility model discloses a hybrid excitation stator surface-mounted double salient pole motor with a modular rotor, including a stator core 1, a three-phase centralized armature winding 2, a rotor core 3, and a permanent magnet 4. Single-phase centralized excitation winding 5 and magnetic isolation mechanism 6. The hybrid excitation stator surface mount double salient pole motor adopting the modularized rotor of the utility model includes two parts, the stator and the rotor, which can be in the form of an inner rotor or an outer rotor according to different application occasions. Both the stator core 1 and the rotor core 3 are salient pole structures, and the stator 1 is provided with a concentrated armature winding 2 , a permanent magnet 4 and a concentrated field winding 5 . The stator teeth are divided into two groups, namely the stator teeth with permanent magnets (called permanent magnet teeth) and the stator teeth with armature coils (called armature teeth), and the armature teeth and permanent magnet teeth Alternate distribution. The permanent magnets are all radially magnetized, and each permanent magnet is mounted on the surface of a stator permanent magnet tooth facing the rotor, and the magnetization direction of two adjacent permanent magnets is opposite, that is, the first stator permanent magnet tooth If the polarity distribution of the permanent magnets is N-S, then the polarity of the permanent magnets under the adjacent permanent magnet teeth of the stator after one armature tooth is separated is S-N, and they are staggered and distributed on the surface of the stator in turn. The material of the permanent magnet is other permanent magnet materials such as ferrite or NdFeB. The rotor is composed of a U-shaped rotor core 3 and a magnetic isolation mechanism 6, and the lower ends of each U-shaped magnetic core are respectively embedded in the magnetic isolation mechanism, and the rotor part has neither permanent magnets nor windings. The rotor core 3 is made of magnetically conductive materials such as silicon steel sheets, and the magnetic isolation mechanism may be made of nonmagnetically conductive materials such as copper and aluminum.

The coils of the three-phase centralized armature winding 2 are respectively sleeved on a stator armature tooth, and the coil 201 and the coil 204 are connected in series to form an A-phase armature winding; the coil 202 and the coil 205 are connected in series to form a B-phase armature winding; The coil 203 and the coil 206 are connected in series to form a C-phase armature winding. As the rotor of the motor rotates, the flux linkage with bipolar changes will be turned in each coil of the armature winding, thereby generating an alternating induced electromotive force.

The concentrated excitation winding 5 has a total of six concentrated coils, which are respectively placed on the six permanent magnet teeth of the stator. Wherein the first excitation winding coil 501, the second excitation winding coil 502, the third excitation winding coil 503, the fourth excitation winding coil 504, the fifth excitation winding coil 505, and the sixth excitation winding coil 506 are centralized coils connected in series, Form a single-phase field winding. Therefore, two coils of the armature winding 2 and the field winding 5 are distributed in each stator slot, and each has a coil edge. It should be noted that, in the motor of the present invention, only one permanent magnet is pasted under each permanent magnet tooth of the stator, and the armature flux linkage changes in bipolarity, so that the utilization rate of the permanent magnet is significantly higher than that of the reverse double-convex magnetic flux pole permanent magnet motors and conventional stator surface mount permanent magnet motors.

The rotor composed of U-shaped rotor core 3 and magnetic isolation mechanism 6 can be a straight slot rotor, which ensures that the motor of the utility model can obtain permanent magnet flux linkage and no-load induced potential of each phase very close to trapezoidal wave or sine wave distribution. static features. In addition, the rotor chute can also be angled to obtain a more sinusoidal armature induction potential, which makes the control mode of the motor of the present invention more flexible and adapts to different AC speed regulation and servo drive occasions.

As shown in FIG. 2 , the rotor U-shaped iron cores 3 can be connected together through a connecting bridge 7 , so that the motor rotor iron cores are integrated. The internal magnetic field of the connecting bridge 7 is highly saturated, so that the magnetic permeability of the connecting bridge is close to air, which can significantly weaken the magnetic flux leakage, so that the connecting bridge has no magnetic conduction effect, and only plays the role of connecting the rotor U-shaped magnetically permeable core unit as a whole .

3A and 3B are working principle diagrams of the motor of the present invention. It can be seen from Figure 3A and Figure 3B that at the position of the rotor shown in the figure, after the excitation current is passed into the excitation winding, the excitation flux chain generated by each excitation coil and the permanent magnet mounted under the permanent magnet tooth where it is located are generated. When the direction of the permanent magnet flux linkage is the same, the electric excitation magnetic field plays the role of enhancing the permanent magnet excitation magnetic field at this time, thereby increasing the excitation flux linkage and induced electromotive force of the turn chain in the armature winding, which is the electric excitation magnetism of the magnetization property. chain; after changing the current direction of the excitation winding, the excitation flux chain generated by each excitation coil is opposite to the permanent magnet flux chain generated by the permanent magnet mounted under the permanent magnet tooth, and the electric excitation magnetic field can weaken the permanent magnet. The action of the excitation magnetic field further reduces the excitation flux linkage and induced electromotive force of the turn chain in the armature winding, which is the electric excitation flux linkage of demagnetization property. By changing the direction and magnitude of the current passed into the excitation winding, the effect of adjusting the excitation magnetic field can be achieved, which is the principle of hybrid excitation. Magnetization direction 4-1, permanent magnet flux linkage 8, magnetization property electric excitation flux linkage 9, demagnetization property electric excitation flux linkage 10. When the electric excitation winding in Fig. 3A is fed with the current of magnetization property, the electric excitation flux generated by each centralized excitation coil is in the same direction as the permanent magnet flux generated by the permanent magnet mounted on the permanent magnet teeth of the stator. The electric excitation magnetic field strengthens the permanent magnet magnetic field, and the direction of the excitation current is changed in Fig. 3B, then the electric excitation flux generated by each concentrated excitation coil is opposite to the permanent magnet flux generated by the permanent magnet mounted on the permanent magnet tooth of the stator. At this time, the electric excitation magnetic field weakens the permanent magnetic field.

Figure 4 and Figure 5 respectively show the phase A armature winding in pure permanent magnet (that is, pure permanent magnet excitation), magnetization (that is, the joint action of magnetization property electric excitation and permanent magnet excitation) and demagnetization (that is, demagnetization property electric excitation The no-load single-turn flux linkage waveform and the induced potential waveform under the three excitation conditions. With the direction of the current flowing into the excitation winding, the direction of the electric excitation flux is the same as or opposite to that of the permanent magnet excitation flux, which respectively enhance the excitation field (that is, magnetization) or weaken the excitation field (that is, demagnetization).

The above are only preferred embodiments of the present utility model, and the protection scope of the present utility model is not limited to the above-mentioned embodiments, but any equivalent modification or change made by those of ordinary skill in the art according to the content disclosed in the present utility model, All should be included in the scope of protection described in the claims.

Claims (11)

1. A hybrid excitation stator surface mount double salient pole motor with a modular rotor, the motor includes: stator (1), concentrated armature winding (2), rotor core (3), permanent magnet (4 ), a single-phase concentrated excitation winding (5) and a magnetic isolation mechanism (6); it is characterized in that: the stator core (1) and the rotor core (3) are salient pole structures; the stator teeth are divided into two groups, namely Permanent magnet teeth attached with permanent magnets and armature teeth covered with armature winding coils, and the armature teeth and permanent magnet teeth are alternately distributed; the coils of the concentrated armature winding (2) are respectively sleeved on a stator on the pivot teeth; the permanent magnets (4) are respectively mounted on the surface of a stator permanent magnet tooth facing the rotor, and each permanent magnet is radially magnetized, and the magnetization direction of two adjacent permanent magnets is opposite; the said The coils of the concentrated excitation winding (5) are respectively set on a stator excitation tooth, and each excitation coil is connected in series to form a single-phase excitation winding; the rotor is composed of a U-shaped magnetically permeable rotor core (3) and a magnetic isolation mechanism (6) , and each U-shaped magnetically permeable rotor core (3) is respectively embedded in the magnetic isolation mechanism (6); the U-shaped magnetically permeable core units of the rotor can be connected together through the connecting bridge (7), because the connecting bridge (7 ) The internal magnetic field is highly saturated and the magnetic resistance is large, which can effectively prevent magnetic flux leakage. 2. The hybrid excitation stator surface mount type double salient pole motor according to claim 1, characterized in that the stator core (1) and the rotor core (3) are both salient pole structures, and the stator It includes a stator core (1), a concentrated armature winding (2), a permanent magnet (4) and a concentrated field winding (5), and the rotor includes a U-shaped rotor core (3) and a magnetic isolation mechanism (6) . 3. The hybrid excitation stator surface-mounted double salient pole motor according to claim 1, characterized in that the direction of the current flowing into the excitation winding is different, and the direction of the electric excitation flux is the same as or opposite to that of the permanent magnet flux, wherein, When the excitation current of the magnetization property is passed in, the electric excitation flux generated by each excitation coil is in the same direction as the permanent magnet flux generated by the permanent magnet mounted under the permanent magnet tooth of the stator, and the electric excitation achieves the magnetization effect; when When the excitation current of demagnetization property is passed through, the electric excitation flux generated by each excitation coil is opposite to the permanent magnet flux generated by the permanent magnet mounted under the permanent magnet tooth of the stator, and the electric excitation reaches the demagnetization effect. 4. The hybrid excitation stator surface mount type double salient pole motor according to claim 1, characterized in that, there is winding complementarity between the armature winding coils forming one phase, and the armature induced potential is a sine wave or a square Wave. 5. The hybrid excitation stator surface mount double salient pole motor according to claim 1, characterized in that, according to the specific stator and rotor cogging fit, each coil of the centralized armature winding (2) can be Connected into a single-phase or multi-phase armature winding; the centralized armature winding (2) can be in the form of a distributed winding. 6. The hybrid excitation stator surface mount type double salient pole motor according to claim 1, characterized in that, each of the permanent magnets (4) is radially magnetized, and the charge of two adjacent permanent magnets The magnetic directions are opposite; the permanent magnet (4) is ferrite or NdFeB permanent magnet material. 7. The hybrid excitation stator surface mount double salient pole motor according to claim 1, characterized in that the rotor core (3) can be connected as a whole through a connecting bridge (7). 8. The hybrid excitation stator surface mount double salient pole motor according to claim 1, characterized in that the rotor core (3) and the magnetic isolation mechanism (6) are located outside the stator (1) and become the outer rotor structure. 9. The hybrid excitation stator surface mount double salient pole motor according to any one of claims 1-8, characterized in that the stator core (1), the rotor core (3) and the connecting bridge (7) All materials are magnetically permeable materials of silicon steel sheets. 10. The hybrid excitation stator surface mount double salient pole motor according to any one of claims 1-8, characterized in that the material of the magnetic isolation mechanism (6) is non-magnetic materials such as copper and aluminum . 11. The hybrid excitation stator surface mount double salient pole motor according to any one of claims 1-8, characterized in that the motor can operate as a generator or a motor.

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