CN1945958A - Driving method and device for permanent magnetic motor rotor - Google Patents

Abstract

This invention relates to a drive method for permanent magnet motor rotors and a device including a rotor and a stator relatively fixed to the shell, in which, the rotor is a pair of axial polar magnets inserted on a plate, the N and S poles of two adjacent magnets are opposite, the stator is made of magnet-conduction materials and set with two sets of same number of convex poles at either side of the plate, the corresponding salient poles of the two sets of salient poles are staggered on the circle direction, so that the central axes of the magnets at the balance state between the two poles and coupled with them is staggered with that of the stator salient pole with a winding connected with the controller on it, the controller is connected with the sensor sensing the rotation angle of the rotor.

Description

Method and device for driving rotor of permanent magnet motor

technical field

The invention belongs to the technical field of motors, in particular to permanent magnet motors.

Background technique

Existing permanent magnet motors and switched reluctance motors that use permanent magnets as rotors have difficulty in starting. Generally, the starting current is about 5-6 times the rated current, while the starting torque is only about 0.8-1.2 times the rated torque. Therefore, it consumes a lot of energy, and has the disadvantages of large volume and weight, many consumables, and complex structure.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method and device for driving the rotor of a permanent magnet motor. The permanent magnet motor designed by this method has the advantages of easy starting, small starting current, strong overload capacity, energy saving, simple structure and small volume. , light weight and long service life.

The driving method of the permanent magnet motor rotor of the present invention is (referring to embodiment figure): be provided with stator (4), rotor (5), permanent magnet (6) is set on rotor, described stator is made of magnetically conductive material , and there are salient pole pairs (4a, 4b) that can be coupled with each rotor permanent magnet (6), and it is characterized in that: the stator salient poles (4a), (4b) that make up each stator salient pole pair are along the rotor The circumferential direction of operation is staggered by an angle, so that the central axis of the rotor permanent magnet balanced between the two is staggered from the central axis of the salient pole of the stator, and the salient pole of the stator is provided with a winding (13) electrically connected to the controller. When the rotor permanent magnet and the stator salient poles attract each other and move to the equilibrium position between the two salient poles corresponding to the stator salient poles with a circumferential staggered angle, the energization of the stator winding will generate a tangential force on the rotor permanent magnet, and turn out of the equilibrium position. The next permanent magnet of opposite polarity is drawn in, thereby keeping the rotor in continuous rotation.

Adopt the permanent magnet motor structure of the inventive method as (referring to embodiment figure): be provided with casing (8), be provided with the rotor (5) that is contained on the main shaft (1) in the casing, relatively fixed stator with casing (4) It is characterized in that: the rotor (5) is a disc of non-magnetic material with a distance in the circumferential direction and embedded with no less than a pair of permanent magnets (6) with axial polarity, The N and S poles of two adjacent permanent magnets are arranged in opposite polarities, and the stator (4) is made of magnetically permeable material, and is provided with two groups of salient poles (4a, 4b) with the same number, and the two groups of salient poles are respectively Located on both sides of the disc body of the rotor (5), the corresponding salient poles of the two sets of salient poles form a salient pole pair, and the two salient poles of each salient pole pair are staggered at an angle in the circumferential direction, so that the The two salient poles are coupled in balance, and the central axis of the permanent magnet is staggered from the central axis of the stator salient pole. The stator salient pole is provided with a winding (13) electrically connected to a controller, and the controller is electrically connected to a sensor capable of sensing the rotation angle of the rotor.

The working principle of the device of the present invention is: when static, the permanent magnet installed on the rotor and the stator made of magnetically permeable material attract each other, and turn between the two salient poles (4a, 4b) of the stator salient pole pair, and the axial permanent The N and S poles of the magnet attract each other and are in balance with the two salient poles located on both sides of the rotor disc. Since the two stator salient poles are staggered by an angle in the circumferential direction, the central axis of the permanent magnet and the center of the two stator salient poles The axis is staggered to avoid the "dead point" where the circumferential torque cannot be generated when the permanent magnet coincides with the central axis of the salient pole. The electromagnetic field force (circumferential torque) makes the permanent magnet rotate out of the equilibrium position, and at the same time, the stator salient pole winding attracts the next-level permanent magnet with opposite polarity between the salient pole pairs, and then energizes through the stator winding The tangential force of the permanent magnet is rotated out of this equilibrium position, thus completing the continuous rotation of the rotor.

The present invention can make the permanent magnet always be in the position of staggered angle with the central axis of the salient pole of the stator when the stator winding is energized, so as to ensure that the circumferential torque can be generated between the salient pole of the stator and the rotor, so that the rotor can rotate, and it is easy to start , the advantage of small start-up current, since the rotor of the present invention does not have a winding, there is no armature reaction, which reduces the operating current. The start-up current of the present invention can be 50% of the operating current after load, and in addition, during the above-mentioned rotation process of the rotor, a part The work is performed intermittently by the magnetic attraction force between the permanent magnet and the stator, and part of the work is performed intermittently by the energized electromagnetic field, which can make full use of the magnetic field force, so it has obvious energy-saving effects, and has high working efficiency and large starting torque. The salient poles of the stator of the device are arranged on both sides of the axial direction of the rotor, which reduces the radius and has the advantages of simple structure, small size, light weight and long service life.

Description of drawings

Fig. 1, the schematic diagram of the structure of the embodiment of the device of the present invention

Figure 2, Figure 1 A-A structural schematic diagram of the rotor 5

Fig. 3 and Fig. 1 are schematic diagrams of the relative positions of the stator salient poles 4a and 4b coupled with the permanent magnet 6 on both sides of the rotor in the H direction

Figure 4, schematic diagram of the working process of the rotor permanent magnet 6 and the stator salient poles 4a, 4b in the embodiment of Figure 1 (this figure is to rotate the actual positions of the permanent magnet 6 and the stator salient pole 4 to the center of the circle by 90 degrees to intuitively illustrate The change of the relative angle between them during the working process)

1-Spindle 2-End plate 3-Adjusting disc 4-Stator 4a, 4b-Salient pole of stator 5-Rotor 6-Permanent magnet 7-Positioning sleeve 8-Case 9-Adjusting rod 10-Sensor 11-Fan 12-Dustproof Cover 13-Winding

Specific implementation plan:

The structure of the permanent magnet motor adopting the method of the present invention is as follows: referring to Fig. 1 , the two ends of the casing 8 are equipped with end plates 2 through screws, and the main shaft 1 is connected with the end plates 2 at the two ends of the casing 8 through bearings. Two sets of rotors 5 and stators 4 with the same structure are mounted on both sides of the main shaft 1 and separated by positioning sleeves 7 .

The structure of each group of rotors and stators is: the rotor 5 fixed on the main shaft 1 through a keyway is a disc body, which is potted with reinforced fiber resin, as shown in Figure 2, and the permanent magnet 6 is evenly embedded in the rotor circle in the circumferential direction. On the disk body, the directions of N and S poles of the permanent magnets are parallel to the direction of the main axis, and the polarities of adjacent permanent magnets are opposite. The stator 4 is a salient pole structure formed by lamination of double-sided insulated cold-rolled silicon steel sheets. , windings 13 are wound on the salient poles, and the salient poles of the stator are divided into two groups 4a, 4b with the same number, which are respectively fixed on both sides of the disc rotor 5 by screws, which are relatively fixed with the casing 8 and facing the On the adjusting disk 3 on the surface of the rotor disk, the windings of two groups of salient poles are respectively connected in series or in parallel. In this example, six permanent magnets are evenly arranged on the upper circumference of the rotor 5, and each group of stators located on both sides of the rotor has three salient poles, separated by 120 degrees, and the windings 13 on each group of three salient poles are connected in series or in parallel. The two stator salient poles corresponding to each other on both sides of the rotor disk are staggered by 20 degrees in the circumferential direction (see Figure 3). The salient poles 4a, 4b can be respectively coupled with the two poles of the permanent magnet 6 rotating therebetween, and the permanent magnet can be balanced between the two stator salient poles 4a, 4b under the magnetic attraction force with the two salient poles.

In this example, two sets of four adjustment discs 3 are respectively connected to the casing 8 through screws, and an angle adjustment rod 9 is connected between the adjustment discs 3 at both ends, and the stator fixed on it can be adjusted synchronously by adjusting the angles of the adjustment discs at both ends. The angular size of the circumferential stagger between the salient poles and the corresponding stator salient poles on the inner adjustment disk.

In the present invention, the angular size of the circumferential stagger of the corresponding stator salient poles located on both sides of the rotor disk body cannot be too large, so that the permanent magnet 6 located between the two salient poles can be balanced by the magnetic field force generated by coupling with the two salient poles Between the two salient poles, on the other hand, it cannot be too small, so that the central axis of the permanent magnet balanced therebetween and the central axis of the two salient poles are staggered by a certain distance, so that a circumferential torque can be generated. For the rotor in which 3 pairs of 6 permanent magnets are evenly provided in this example, the staggered angle of corresponding stator salient poles on both sides of the rotor is preferably 18°-25°.

The sensor 10 that can sense the rotation angle of the rotor 5 is installed on the end plate of the casing 8, the sensor signal output end is connected to the CPU controller, the stator winding 13 is connected to the power supply through the CPU controller, and the main shaft of the end plate 2 on one side is extended 1 is equipped with a fan 11, and the fan 11 is provided with a dust cover 12 relatively fixed with the end plate.

The installation procedure of this permanent magnet motor is: first install the salient poles of the stator on the adjusting disc 3, then fix the two inner adjusting discs and positioning sleeve screws in the middle of the axial direction of the casing, and then install the main shaft rotor and the outer There are two adjustment plates, and the main shaft is fixed on the end plates on both sides through the bearing seat. An angle adjustment rod 9 is connected between the two outer adjustment plates, which can be used to synchronously adjust the salient poles on the two outer adjustment plates to correspond to the two inner adjustment plates. The salient poles are staggered at an angle in the circumferential direction, and then the adjusting plate with the adjusted angle is relatively fixed with the casing by screws.

See Figure 4 for a schematic diagram of the working process of the permanent magnet 6 of the permanent magnet motor rotor and the salient poles of the stator in this example. Angle, the stator salient pole 4a on the outer ring in the figure represents the salient pole located outside the rotor disc, the stator salient pole 4b on the inner ring represents the salient pole located on the inner side of the rotor disc, and the salient poles 4a and 4b on both sides of the rotor are circumferentially staggered by about 20 degrees, in the static state of no power, the rotor permanent magnets 61, 63, 65 and the corresponding stator salient pole pairs made of magnetically permeable materials attract each other, generate torque, and move to the salient pole pairs that are circumferentially staggered. Between the poles 4a and 4b (as shown in Figure 4-1), the two poles of the permanent magnet are attracted to the two salient poles respectively, and are in a balanced state. At this time, a positive pulse current is added to the three outer stator windings 4a to form an N pole , through mutual attraction with the outer S poles of the permanent magnets 61, 63, 65, a leftward tangential force pulse is generated on the rotor, causing it to rotate leftward and turn to the position in Figure 4-2 through inertia, and then the permanent magnets 62, 64 , 66 are attracted to the equilibrium position between the corresponding salient pole pairs shown in Figure 4-3 by the magnetic attraction force with the salient poles of the stator. At this time, a negative pulse current is added to the inner stator winding 4b to form an S pole. By repelling the S pole inside the permanent magnet, the permanent magnet can be rotated to the left, and this cycle realizes the continuous rotation of the rotor.

The power-on moment is controlled by the CPU controller, and the controller obtains the signal of the rotor rotation angle through the sensor. Whenever the rotor turns to the set angle (between the stator salient pole pairs with staggered angles), the controller controls the set inner or outer winding Power on to realize the function of pushing the rotor. If the rotor can be turned to the left according to the aforementioned energization direction, then changing the energization direction can make the rotor turn to the right, all of which can be controlled by the CPU controller.

In this example, the rotor rotates once every 6 steps, and the inner and outer windings are energized 3 times each time, each step turns 60 degrees, and the work is done by the permanent magnet for about 30 degrees, and the work is done by the energized electromagnetic field for about 30 degrees, and the starting current is small. , so the energy-saving effect is remarkable, and the two rotors of this machine are driven by four sets of windings, the controller can choose to energize one or more windings according to the size of the load, for example, when the load is heavy, the controller controls the four windings Power on to realize full-load drive, and when the load is light (such as when the electric vehicle is going downhill), part or all of the windings can be controlled to become power generation windings to charge the storage battery, so as to realize energy complementarity under two working environments of light load and heavy load, and make reasonable use of them. Energy, avoid the waste of electric energy at light load like other motors, and further achieve the purpose of high efficiency and energy saving.

This example has good energy saving effect, and has the characteristics of small size, light weight, simple structure, high working efficiency and large starting torque.

Claims (8)

1, the driving method of permanent magnet motor rotor, be provided with stator (4), rotor (5), permanent magnet (6) is set on rotor, described stator is made of magnetic material, and is provided with and can be connected with each A rotor permanent magnet (6) corresponding to coupled salient pole pairs (4a, 4b), characterized in that: the stator salient poles (4a), (4b) forming each stator salient pole pair are staggered by angle along the circumferential direction of the rotor, To make the central axis of the permanent magnet of the rotor balanced between the two and the central axis of the salient pole of the stator stagger, the salient pole of the stator is provided with a winding (13) electrically connected to the controller, whenever the permanent magnet of the rotor and the salient pole of the stator When the mutual attraction moves to the equilibrium position between the two salient poles corresponding to the circumferential staggered angle of the stator salient pole pair, energizing the stator winding will generate a tangential force on the rotor permanent magnet, turn out of the equilibrium position, and at the same time suck in the next pole with the opposite polarity. Permanent magnets to keep the rotor turning continuously. 2. The permanent magnet motor is provided with a casing (8), a rotor (5) mounted on the main shaft (1) and a stator (4) relatively fixed to the casing are arranged in the casing, and it is characterized in that: The rotor (5) of the rotor (5) is a permanent magnet (6) with not less than a pair of axial polarity embedded in the circumferential direction on the disk body of the non-magnetic material, and the N and S poles of the two adjacent permanent magnets The polarities are oppositely arranged, the stator (4) is made of magnetically permeable material, and is provided with two sets of salient poles (4a, 4b) with the same number, and the two sets of salient poles are respectively arranged on the two sides of the rotor (5) disc body. On the side, the corresponding salient poles of the two sets of salient poles form a salient pole pair, and the two salient poles of each salient pole pair are staggered at an angle in the circumferential direction, so that the permanent magnet that enters between the two salient poles and is coupled with the two salient poles in a balanced state The central axis is staggered with the central axis of the salient poles of the stator, and the salient poles of the stator are provided with windings (13) electrically connected to a controller, and the controller is electrically connected to a sensor capable of sensing the rotation angle of the rotor. 3. The permanent magnet motor according to claim 2, characterized in that: the rotor (5) is a disc body, and the permanent magnets (6) are evenly embedded in the rotor disc body in the circumferential direction, permanently The directions of N and S poles of the magnets are parallel to the direction of the main shaft, and the polarities of the adjacent permanent magnets are opposite. The stator salient poles are divided into two groups (4a) and (4b) with the same number, which are respectively fixed on the disc rotor (5 ) on both sides of the adjusting disc (3) which is relatively fixed to the casing (8) and faces the rotor disc surface, the windings of the two sets of salient poles are respectively connected in series or in parallel. 4. The permanent magnet motor according to claim 2, characterized in that six permanent magnets are evenly arranged on the upper circumference of the rotor (5), and each set of stators located on both sides of the rotor has three salient poles, separated by 120 degrees. 5. The permanent magnet motor according to claim 4, wherein each pair of salient poles of the stator corresponding to each other on both sides of the rotor are staggered by 18-25 degrees in the circumferential direction. 6. The permanent magnet motor according to claim 2, characterized in that: the sensor (10) capable of sensing the rotation angle of the rotor is installed on the end plate of the casing (8). 7. The permanent magnet motor according to any one of claims 2-6, characterized in that: there are two sets of rotors (5) and stators (4) with the same structure, which are respectively mounted on the main shaft (1) The two sides are separated by positioning sleeves (7). 8. The permanent magnet motor according to claim 3, characterized in that: there are two sets of rotors (5) and stators (4) with the same structure, which are installed on both sides of the main shaft (1) respectively, and are fixed with positioning sleeves (7) separates, and is connected with adjusting rod (9) between the adjusting discs (3) at both ends.

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