CN204244042U - Wound-rotor type induction-type bearingless motor - Google Patents

Abstract

A kind of Wound-rotor type induction-type bearingless motor, comprise stators and rotators, described stator setting pilot trench, install three-phase torque winding and three-phase suspending windings in stator slot, rotor established by described rotor, installs three-phase rotor windings in rotor, the number of poles of every phase torque winding is 4, the number of poles of every phase suspending windings is 2, and the number of poles of every phase rotor windings is 4, and in stator, in three-phase torque winding and rotor, three-phase rotor windings uses the electric current of same frequency characteristic frequency to input.Compared with squirrel-cage induction-type bearingless motor, the present embodiment can produce larger radial load and more stable torque.The present embodiment can make double-fed type induction-type bearingless motor, be used in wind power generation field, adopt Wound-rotor type structure, frequency converter can be added in Wound-rotor type winding automatically to regulate, unit can realize constant frequency generation under different rotating speeds, satisfied electric loading and grid-connected requirement, energy-conserving and environment-protective, efficiency are high.

Description

Wound Bearingless Asynchronous Motor

technical field

The utility model relates to an asynchronous motor, in particular to a bearingless asynchronous motor.

Background technique

In recent years, domestic and foreign scholars' research on bearingless motors is basically based on the structure of the squirrel-cage rotor. The rotor magnetic field of the squirrel-cage motor is composed of two parts, one part is generated by the driving magnetic field induction, and the other part is generated by the levitation magnetic field. produced by induction. The interaction between the rotor magnetic field and the suspension magnetic field will generate additional torque, which will have a bad influence on the rotor torque performance. Usually, it is shown that the rotor magnetic field and the levitation magnetic field of the squirrel-cage bearingless asynchronous motor are coupled with each other. This is mainly because the rotor induced current of the conventional squirrel-cage bearingless asynchronous motor not only generates a magnetic field corresponding to the torque winding but also generates a magnetic field corresponding to the suspension winding, which can interact with the suspension magnetic field to generate another torque component, That is, the torque of the squirrel-cage asynchronous motor consists of two parts. One is generated by the torque winding current and the other by the levitation winding current, which makes the torque dependent on the levitation winding current. It will make the system control part more complicated.

Utility model content

The purpose of the utility model is to provide a winding type bearingless asynchronous motor, which solves the technical problem that the induced magnetic field of the torque winding and the suspension winding in the existing bearingless asynchronous motor cannot decouple the control of the rotor.

The winding type bearingless asynchronous motor of the utility model includes a stator and a rotor. The stator is provided with a sub-slot, and a three-phase torque winding and a three-phase suspension winding are installed in the stator slot. The rotor is provided with a rotor slot. Install the three-phase rotor winding, the number of poles of each phase torque winding is 4, the number of poles of each phase suspension winding is 2, the number of poles of each phase rotor winding is 4, the three-phase torque winding in the stator and the three-phase rotor in the rotor The windings use a current input of the same frequency characteristic frequency.

The number of stator slots is 36, and the number of rotor slots is 24.

The u-phase torque windings (u1, u2, u3, u4) of the three-phase torque windings in the stator are arranged in stator slots 1, 10, 19, and 28, and the v-phase torque of the three-phase torque windings in the stator The windings (v1, v2, v3, v4) are set in the stator slots 4, 13, 22, 31, and the w-phase torque windings (w1, w2, w3, w4) of the three-phase torque windings in the stator are set in the stator slots Bits 7, 16, 25, 34.

The u-phase torque windings (u9, u0) of the three-phase suspension windings in the stator are arranged in the stator slots 8 and 26, and the v-phase torque windings (v9, v0) of the three-phase suspension windings in the stator are arranged in the stator slots 14, 32, the w-phase torque winding (w9, w0) of the three-phase suspension winding in the stator is set in the slot 20, 2 of the stator.

The u-phase rotor windings (u5, u6, u7, u8) of the three-phase rotor windings in the rotor are arranged in stator slots 1, 7, 13, and 19, and the v-phase rotor windings (v5, v6) of the three-phase rotor windings in the rotor , v7, v8) are set in stator slots 3, 9, 15, 21, and the w-phase rotor windings (w5, w6, w7, w8) of the three-phase rotor windings in the rotor are set in stator slots 5, 11, 17, 23 middle.

In the winding type bearingless asynchronous motor of the utility model, the torque is only produced by the interaction between the quadrupole torque magnetic field and the quadrupole rotor induced current. The levitation field does not produce a steady torque because the rotor field and the levitation field have different numbers of pole pairs. The utility model introduces the structure of the wound rotor into the bearingless asynchronous motor, and through the design of the winding structure, the structure of the wound rotor has the advantages that the squirrel-cage structure does not have. The rotor winding is connected to the power grid through a frequency converter, and the frequency, voltage, amplitude and phase of the power supply of the rotor winding are automatically adjusted by the frequency converter according to the operation requirements. Require. Due to the use of AC excitation, the generator and the power system constitute a "flexible connection", that is, the excitation current can be adjusted according to the grid voltage, current and generator speed, and the output voltage of the generator can be precisely adjusted to meet the control requirements.

The setting method of the utility model has a good effect on reducing the complexity of the control system for calculating the rotor eccentricity, and can obviously reduce the cost of the control system while ensuring the thickness of the air gap between the stator and the rotor.

Embodiments of the utility model will be further described below in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is the structural representation of the utility model winding type bearingless asynchronous motor;

Fig. 2 is a schematic diagram of the effect of the winding type bearingless asynchronous motor of the present invention on improving the radial force of the rotor;

Fig. 3 is a schematic diagram of the effect of improving the torque response of the rotor of the winding type bearingless asynchronous motor of the present invention.

Detailed ways

As shown in Figure 1, this embodiment includes torque windings and suspension windings installed in the stator slots, and the rotor windings installed in the rotor slots, the number of stator slots is 36, the number of rotor slots is 24, and the stator uses Three-phase torque windings, the number of poles of each phase torque winding is 4 (number of pole pairs is 2), and three-phase suspension windings are also used in the stator, the number of poles of each phase suspension winding is 2 (number of pole pairs is 1), Three-phase rotor windings are used in the rotor, and the number of poles of each phase rotor winding is 4 (the number of pole pairs is 2).

Slots parallel to the axis on the circumference of the stator and rotor are evenly distributed along the corresponding circumference.

The u-phase torque windings (u1, u2, u3, u4) of the three-phase torque windings in the stator are arranged in slots 1, 10, 19, and 28 of the stator, and the v-phase torque windings of the three-phase torque windings in the stator ( v1, v2, v3, v4) are set in the stator slots 4, 13, 22, 31, and the w-phase torque winding (w1, w2, w3, w4) of the three-phase torque winding in the stator is set in the stator slot 7 , 16, 25, 34;

The u-phase torque windings (u9, u0) of the three-phase suspension windings in the stator are arranged in stator slots 8 and 26, and the v-phase torque windings (v9, v0) of the three-phase suspension windings in the stator are arranged in stator slots 14 and 26. 32. The w-phase torque winding (w9, w0) of the three-phase suspension winding in the stator is set in the stator slot 20, 2;

The u-phase rotor windings (u5, u6, u7, u8) of the three-phase rotor windings in the rotor are arranged in stator slots 1, 7, 13, and 19, and the v-phase rotor windings (v5, v6, v7) of the three-phase rotor windings in the rotor , v8) are arranged in stator slots 3, 9, 15, 21, and the w-phase rotor windings (w5, w6, w7, w8) of the three-phase rotor windings in the rotor are arranged in stator slots 5, 11, 17, 23;

The three-phase torque winding in the stator and the three-phase rotor winding in the rotor use the current input of the same frequency characteristic frequency, and the three-phase suspension winding in the stator and the three-phase rotor winding in the rotor use the current input of different frequency characteristic frequency.

The windings of each phase are connected through corresponding collector loops.

This embodiment can generate a stable levitation force to keep the rotor in a stable levitation. The rotor magnetic field generated by the rotor current of a wound bearingless asynchronous motor can enhance the radial force. At the same time, the rotating magnetic field generated by the levitation winding and the rotating magnetic field generated by the torque winding have different speeds. The rotor magnetic field generated by the induced rotor current is uniformly distributed and has the same rotational speed as the torque field. Therefore, it is able to force a radial force. In addition, the torque can only be produced by the interaction of the four-pole torque magnetic field and the four-pole rotor induced current. The suspension magnetic field does not interact with the rotor magnetic field to generate torque, because the rotor magnetic field and the suspension magnetic field have different numbers of pole pairs, therefore, in the wound type bearingless asynchronous motor, the magnetic field coupling relationship is smaller than that of the squirrel cage type bearingless asynchronous motor structure Keep it simple. This is of great significance to the decoupling control of bearingless asynchronous motors.

As shown in Figure 2, using the characteristics of this embodiment, the model of the three-phase two-degree-of-freedom winding bearingless asynchronous motor established by using the Ansoft/Maxwell3D tool, compared with the squirrel-cage bearingless asynchronous motor, this embodiment Can generate larger radial force and more stable torque. This embodiment can be made into a double-fed bearingless asynchronous motor, which is used in the field of wind power generation. It adopts a winding structure, and a frequency converter can be added to the winding winding for automatic adjustment. The unit can realize constant frequency power generation at different speeds , meet the requirements of electric load and grid connection, energy saving, environmental protection, and high efficiency. This embodiment has the characteristics of no friction, long life, low maintenance, high reliability, large torque, and more stable radial force. It is applied to wind power generators, which can effectively improve the service life of wind power generators and greatly reduce maintenance costs. Improve reliability.

As shown in Figure 3, after the present embodiment adopts the three-phase alternating current of the same current frequency as the input current of the torque winding and the rotor winding, the same current frequency is used as the main control factor, the coupling between the two is tight, and the torque is stable, so that the stator and rotor winding The torque response between the rotors is more sensitive.

The levitation control method of the wound bearingless asynchronous motor adopted in the structure of the above embodiment mainly includes the following steps:

Winding type asynchronous motor is adopted, the torque winding and suspension winding are set on the stator, and the rotor winding is set on the rotor;

The number of pole pairs of the torque winding and the rotor winding is the same, the number of pole pairs of the torque winding - the number of pole pairs of the suspension winding = 1;

The frequency characteristics of the three-phase AC current input to the torque winding and the rotor winding are set to be the same;

The frequency characteristics of the three-phase AC current input into the suspension winding are different from those of the torque winding.

Specifically, the number of stator slots is set to 36, the number of rotor slots is set to 24, the number of poles of the torque winding of each phase is 4, the number of poles of the suspension winding of each phase is 2, and the number of poles of the rotor winding of each phase is 4;

The u-phase torque windings (u1, u2, u3, u4) of the three-phase torque windings in the stator are arranged in slots 1, 10, 19, and 28 of the stator, and the v-phase torque windings of the three-phase torque windings in the stator ( v1, v2, v3, v4) are set in the stator slots 4, 13, 22, 31, and the w-phase torque winding (w1, w2, w3, w4) of the three-phase torque winding in the stator is set in the stator slot 7 , 16, 25, 34;

The u-phase torque windings (u9, u0) of the three-phase suspension windings in the stator are arranged in stator slots 8 and 26, and the v-phase torque windings (v9, v0) of the three-phase suspension windings in the stator are arranged in stator slots 14 and 26. 32. The w-phase torque winding (w9, w0) of the three-phase suspension winding in the stator is set in the stator slot 20, 2;

The u-phase rotor windings (u5, u6, u7, u8) of the three-phase rotor windings in the rotor are arranged in stator slots 1, 7, 13, and 19, and the v-phase rotor windings (v5, v6, v7) of the three-phase rotor windings in the rotor , v8) are arranged in stator slots 3, 9, 15, 21, and the w-phase rotor windings (w5, w6, w7, w8) of the three-phase rotor windings in the rotor are arranged in stator slots 5, 11, 17, 23;

It is verified by simulation software that the rotor is under the control of the suspension winding, the shape of the air gap between the rotor and the stator is good, the concentricity is good, and the offset of the rotor axis to the stator axis is very low.

The above-mentioned embodiments are only described to the preferred implementation of the utility model, and are not limited to the scope of the utility model. Various modifications and improvements made should fall within the scope of protection determined by the claims of the utility model.

Claims (5)

1. A wound type bearingless asynchronous motor, comprising a stator and a rotor, is characterized in that: the stator is provided with a sub-slot, and a three-phase torque winding and a three-phase suspension winding are installed in the stator slot, and the rotor is provided with a rotor slot , the three-phase rotor winding is installed in the rotor slot, the number of poles of each phase torque winding is 4, the number of poles of each phase suspension winding is 2, the number of poles of each phase rotor winding is 4, the three-phase torque winding in the stator is connected with the rotor The three-phase rotor windings in the middle use the current input of the same frequency characteristic frequency. the 2. The wound-type bearingless asynchronous motor according to claim 1, characterized in that: the number of stator slots is 36, and the number of rotor slots is 24. the 3. The wound type bearingless asynchronous motor according to claim 2, characterized in that: the u-phase torque winding (u1, u2, u3, u4) of the three-phase torque winding in the stator is arranged in the stator slot In (1, 10, 19, 28), the v-phase torque windings (v1, v2, v3, v4) of the three-phase torque windings in the stator are set in the stator slots (4, 13, 22, 31), and the stator The w-phase torque windings (w1, w2, w3, w4) of the middle three-phase torque windings are arranged in the stator slots (7, 16, 25, 34). the 4. The wound type bearingless asynchronous motor according to claim 3, characterized in that: the u-phase torque winding (u9, u0) of the three-phase suspension winding in the stator is arranged in the stator slot (8, 26) , the v-phase torque winding (v9, v0) of the three-phase suspension winding in the stator is set in the stator slot (14, 32), and the w-phase torque winding (w9, w0) of the three-phase suspension winding in the stator is set in the stator slot Bit (20, 2). the 5. The wound-type bearingless asynchronous motor according to claim 4, characterized in that: the u-phase rotor winding (u5, u6, u7, u8) of the three-phase rotor winding in the rotor is arranged in the stator slot (1 , 7, 13, 19), the v-phase rotor windings (v5, v6, v7, v8) of the three-phase rotor windings in the rotor are set in the stator slots (3, 9, 15, 21), and the three-phase rotor windings in the rotor The w-phase rotor windings (w5, w6, w7, w8) are arranged in the stator slots (5, 11, 17, 23). the