CN112104126B - Three-phase 24/20-pole distributed electro-magnetic doubly salient wind driven generator - Google Patents

Abstract

The invention relates to a three-phase 24/20-pole distributed electric excitation doubly salient wind driven generator, which comprises a 24/20-pole distributed electric excitation doubly salient motor and a three-phase uncontrolled rectifying diode, wherein the electric excitation doubly salient motor comprises a stator and a rotor, a plurality of stator poles are arranged on the stator, exciting coils are wound on the stator poles, the exciting coils are mutually connected to form exciting coils, armature coils are further wound on the stator poles, the armature coils on the front and rear two stator poles which are separated into two stator poles are mutually connected to form armature windings, the number of the armature windings is 3, the 3 armature windings form three-phase armature windings, one end of each three-phase armature winding is led out and combined together to form a negative pole of the wind driven generator, and the other end of each three-phase armature winding is connected with the three-phase uncontrolled rectifying diode to form a positive pole of the wind driven generator. Compared with the prior art, the invention has the advantages of reducing the voltage fluctuation rate and the torque fluctuation rate of the generator, improving the output capacity of the motor and the like.

Description

A three-phase 24/20 pole distribution electric excitation double salient pole wind power generator

technical field

The invention relates to the technical field of special motors, in particular to a three-phase 24/20 pole distribution electric excitation double salient pole wind power generator.

Background technique

At present, the main types of wind power generators are cage-type asynchronous generators, doubly-fed generators and permanent magnet synchronous generators. and high power density, but the air gap magnetic field cannot be adjusted. High reliability, low-speed direct drive, and high efficiency are the development trends of wind turbines. Electric excitation double salient pole is a new type of brushless motor, its stator and rotor are salient pole cogging structure, armature winding and excitation winding are installed on the stator, and there is no winding on the rotor. The excitation winding on the stator is wound around the armature winding to provide an excitation magnetic field. This structure can easily realize the magnetic field adjustment of the electrically excited double salient pole motor. Since the electric excitation double salient pole motor does not need to use permanent magnets and has no windings, brushes and commutators on the rotor, it has the outstanding advantages of simple structure, high reliability, low cost and easy fault de-excitation. Moreover, the motor and an external rectification circuit can constitute an electrically excited double salient pole brushless DC generator system, and its successful application in a wind power generation system is expected to reduce the cost of the power generation system and improve the reliability of the system.

At present, in the research of wind power generation, electric excitation doubly salient pole generators usually choose multiple stator poles and multiple rotor poles to reduce torque ripple and improve material utilization. Satisfying 6N/4N or 6N/8N (N is an integer), the common stator and rotor poles are 24/16 and 24/32. However, the currently used electrically excited doubly salient pole generators generally adopt a concentrated excitation method, that is, the excitation winding spans multiple stator poles, and each stator pole is wound with an armature winding, which leads to different magnetic circuits of each phase. Symmetry further leads to higher rectified output voltage fluctuation rate and higher torque fluctuation rate, which increases the vibration and noise of the motor.

Contents of the invention

The purpose of the present invention is to provide a three-phase 24/20 pole distribution electric excitation double salient pole in order to overcome the defects of the above-mentioned prior art that the rectification output voltage fluctuation rate and torque fluctuation rate of the electric excitation double salient pole generator are relatively high Wind Turbines.

The purpose of the present invention can be achieved through the following technical solutions:

A three-phase 24/20 pole distribution electrically excited double salient pole wind power generator, comprising a 24/20 pole distributed electrically excited double salient pole motor and a three-phase uncontrolled rectifier diode, the electrically excited double salient pole motor includes a stator and The rotor, the stator is provided with a plurality of stator poles, and the excitation coils are wound on the stator poles, and the excitation coils are connected to each other to form an excitation winding, and the armature coils are also wound on the stator poles, with an interval of two The armature coils on the front and rear two stator poles of a stator pole are connected to each other to form an armature winding. The number of the armature windings is 3, and the 3 armature windings form a three-phase armature winding. The three-phase armature winding One end of the pivot winding is combined to form the negative pole of the wind generator, and the other end is connected to the three-phase uncontrolled rectifier diode as the positive pole of the wind generator to form a full-bridge rectifier circuit.

The electrically excited double salient pole motor is a double salient pole motor with inner rotor or outer rotor structure.

The current applied in the excitation winding is direct current.

The number of the stator poles is 24, and the armature winding includes 8 stator poles.

Further, the electrical angle between two adjacent stator poles in the armature winding is 180°.

The winding directions of the excitation coils adjacent to the stator poles are opposite, so that the excitation windings generate 12 pairs of pole excitation magnetic fields in the air-gap magnetic field, and present distributed excitation magnetic potentials in the air-gap circumferential direction.

The exciting coils are concentrated non-overlapping exciting coils.

The excitation coils are connected in series.

The armature coils are connected in series in the same direction, so that the synthesized electromotive force of the two armature coils is the largest.

Further, the method of connecting in series with each other in the same direction is specifically to connect the head of a single armature coil among the two adjacent armature coils to the tail of the other armature coil.

Compared with the prior art, the present invention has the following beneficial effects:

1. In the present invention, the excitation windings are concentratedly wound on each stator pole, and distributed evenly around the circumference of the stator, so that the magnetic circuits of each phase are symmetrical, and the torque fluctuation and rectified output voltage ripple are reduced.

2. The present invention connects two armature coils in series in the same direction, and the phase difference of the electromotive force vectors of the two armature coils on the stator poles separated by 2 stator poles is 180°, which eliminates the even harmonics and the second harmonic in the back EMF The third harmonic reduces the electromagnetic torque fluctuation rate of the motor.

3. The three-phase armature winding of the present invention adopts a full-bridge rectification circuit, which improves the output capacity of the motor.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the schematic diagram of coil electric potential vector of the present invention;

Fig. 3 is the schematic diagram of full-bridge rectifier circuit of the present invention;

Fig. 4 is the schematic diagram of generator no-load flux linkage of the present invention;

Fig. 5 is the schematic diagram of the no-load back EMF of the generator of the present invention;

Fig. 6 is the schematic diagram of the harmonic component of the generator of the present invention;

Fig. 7 is a schematic diagram of the no-load rectified output voltage of the generator of the present invention.

Reference signs:

1-stator; 2-rotor; 3-stator pole; 4-rotor pole; 5-excitation winding; 6-armature winding; 7-armature coil; L _f+ - the inflow end of excitation current, L _f- - excitation current The outflow end; the first part of the AA phase armature winding; the tail of the XA phase armature winding.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is carried out on the premise of the technical solution of the present invention, and detailed implementation and specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

As shown in Figure 1, a three-phase 24/20 pole distribution electrically excited double salient pole wind turbine includes an electrically excited double salient pole motor with 24/20 pole distribution and a three-phase uncontrolled rectifier diode, and the electrically excited double salient pole The motor includes a stator 1 and a rotor 2. The stator 1 is provided with a plurality of stator poles 3, and the stator poles 3 are wound with field coils. , the armature coils 7 on the two stator poles 3 before and after the two stator poles 3 are connected to each other to form the armature winding 6, the number of the armature winding 6 is 3, and the 3 armature windings 6 form a three-phase electric Armature winding, as shown in Figure 3, one end of the three-phase armature winding is combined together to form the negative pole of the wind turbine, and the other end is connected to the three-phase uncontrolled rectifier diode as the positive pole of the wind turbine to form a full-bridge rectifier circuit.

As shown in Figure 2, the three-phase armature winding includes an A-phase armature winding, a B-phase armature winding and a C-phase armature winding, and the angle between the armature windings is 120°.

The electrically excited doubly salient motor is a doubly salient motor with an inner or outer rotor structure.

The three-phase uncontrolled rectifier diode includes 3 groups of diodes connected in parallel, which are respectively connected to the winding resistance and inductance of the A-phase armature winding, the B-phase armature winding and the C-phase armature winding. A load resistor is provided to form a full-bridge rectifier circuit as a whole.

The current applied in the excitation winding 5 is direct current, the inflow end of the direct current is L _f+ , and the outflow end is L _f− .

The number of stator poles 3 is 24, and the armature winding 6 includes 8 stator poles 3, wherein the A-phase armature winding has a head A and a tail X.

When the rotor pole 4 slides in and out of the stator pole 3, the phase corresponding to the stator pole 3 can supply power to the load, increasing the output power.

The electrical angle between two adjacent stator poles 3 in the armature winding 6 is 180°.

The winding directions of the excitation coils on the adjacent stator poles 3 are opposite, so that the excitation winding 4 generates 12 pairs of pole excitation magnetic fields in the air gap magnetic field, and presents a distributed excitation magnetic potential in the circumferential direction of the air gap, reducing torque fluctuation and rectified output Voltage pulsation.

The excitation coil is a concentrated non-overlapping excitation coil.

The excitation coils are connected in series with each other.

The armature coils 7 are connected in series in the same direction, so that the combined electromotive force of the two armature coils 7 is the largest, and the connection mode in series in the same direction is specifically the head of a single armature coil 7 in two adjacent armature coils 7 It is connected with the tail of another armature coil 7 to eliminate the even harmonic and the third harmonic of the back EMF, and reduce the torque ripple and the harmonic distortion rate of the back EMF.

The no-load flux linkage of the armature windings of the three phases A, B, and C is shown in Figure 4, and the results show that the flux waveforms of each phase are symmetrical; the no-load back EMF of the armature windings of the three phases A, B, and C is shown in the figure As shown in Figure 5, the harmonic components of the no-load back EMF of the armature winding of phase A are shown in Figure 6, there are only odd harmonics in the harmonic components of the no-load back EMF of phase A, and there are no even harmonics, And there are mainly fundamental waves and fifth harmonics, indicating that the present invention can reduce torque ripple and harmonic distortion; the unfiltered no-load rectified output voltage waveform is shown in Figure 7, and the output voltage is only between 140V and 160V fluctuate, and the volatility is low.

In addition, it should be noted that the specific implementation examples described in this specification may have different names, and the above content described in this specification is only an illustration of the structure of the present invention. All equivalent changes or simple changes made according to the structure, features and principles of the concept of the present invention are included in the protection scope of the present invention. Those skilled in the art to which the present invention belongs can make various modifications or supplements or adopt similar methods to the described specific examples, as long as they do not deviate from the structure of the present invention or exceed the scope defined in the claims, all should Belong to the protection scope of the present invention.

Claims (10)

1. The utility model provides a three-phase 24/20 pole distribution electricity excitation doubly salient aerogenerator, its characterized in that includes 24/20 pole distribution's electricity excitation doubly salient motor and three-phase uncontrolled rectifier diode, electricity excitation doubly salient motor includes stator (1) and rotor (2), be equipped with a plurality of stator poles (3) on stator (1), every stator pole is all wound and is had excitation coil, excitation coil interconnect constitutes excitation winding (5), and each excitation coil evenly distributes around stator circumference, makes each looks magnetic circuit symmetry, reduces torque ripple and rectification output voltage pulsation, still winds armature coil (7) on every stator pole (3), and the interval is armature coil interconnect on two stator poles (3) in front and back of two stator poles (3), forms armature winding (6), the quantity of armature winding (6) is 3, and 3 armature winding (6) form three-phase armature winding, the one end of three-phase armature winding draws forth and combines together, constitutes aerogenerator's negative pole, and the other end is connected with three-phase uncontrolled rectifier diode, constitutes the positive bridge of aerogenerator.

2. The three-phase 24/20-pole distributed electro-magnetic doubly salient wind generator of claim 1, wherein the electro-magnetic doubly salient motor is an inner rotor or an outer rotor structure doubly salient motor.

3. A three-phase 24/20 pole distributed electro-magnetic doubly salient wind generator as claimed in claim 1, wherein said current applied in said field winding (5) is dc.

4. A three-phase 24/20 pole distributed electro-magnetic doubly salient wind generator as claimed in claim 1 wherein said number of stator poles (3) is 24 and said armature winding (6) comprises 8 stator poles (3).

5. A three-phase 24/20 pole distributed electro-magnetic doubly salient wind-generator as claimed in claim 4, wherein an electrical angle between two adjacent stator poles (3) in said armature winding (6) is 180 °.

6. A three-phase 24/20 pole distributed electro-magnetic doubly salient wind generator as defined in claim 1 wherein said field coils on adjacent stator poles (3) are wound in opposite directions.

7. The three-phase 24/20 pole distributed electro-magnetic doubly salient wind generator of claim 1 wherein said field coils are concentrated non-overlapping field coils.

8. The three-phase 24/20-pole distributed electro-magnetic doubly salient wind generator according to claim 1, wherein the exciting coils are connected in series.

9. The three-phase 24/20-pole distributed electro-magnetic doubly salient wind generator according to claim 1, wherein the armature coils (7) are connected in series in the same direction.

10. The three-phase 24/20-pole distributed electro-magnetic doubly salient wind generator according to claim 9, wherein the connection mode of mutual homodromous series connection is that the head part of a single armature coil (7) in two adjacent armature coils (7) is connected with the tail part of the other armature coil (7).

Images