CN102055258B - Magnetic pole shoe of salient pole synchronous motor - Google Patents

Abstract

The invention relates to a magnetic pole shoe shape of a salient pole synchronous motor, wherein the magnetic pole consists of a dove tail, a pole body, a pole shoe, a damping winding and an exciting winding. The invention has the advantages that: by changing the shape of the pole shoe, the flux leakage and the air gap magnetomotive force can be reduced, the exiting current can be reduced, the exiting efficiency can be improved and the temperature rise of the exciting winding can be reduced; and the air gap flux density waveform and the no-load voltage waveform can be improved, the aim of improving the quality of electric energy can be achieved and the motor efficiency can be improved. The magnetic pole shoe shape is suitable for the salient pole synchronous motor and is especially suitable for the field of large-sized hydraulic generators.

Description

The magnetic pole pole shoe of salient pole synchronous electric machine

Technical field

The present invention relates to a kind of magnetic pole pole shoe of salient pole synchronous electric machine.

Background technology

As shown in Figure 1, existing magnetic pole pole shoe shape BE is one section circular arc, and AB is parallel with pole body with EF.Motor mainly is made up of stator and rotor two big parts.The rotor of salient pole synchronous electric machine mainly is made up of rotating shaft, support, yoke, magnetic pole, damping winding and excitation winding.Damping winding is installed on the pole shoe, and excitation winding is installed on the magnetic pole pole body.Rotor magnetic pole links to each other with holder part through yoke and together constitutes rotor with rotating shaft.The main effect of rotor is for motor provides constant magnetic flux, in the process of rotation, makes stator winding produce electric energy.The change of magnetic pole pole shoe shape can reduce leakage field and air-gap mmf, reduces exciting current, improves electric efficiency, reduces the excitation winding temperature rise; Improve air gap flux density waveform and floating voltage waveform, improve the quality of power supply.

At present, the magnetic pole pole shoe of salient pole machine generally adopts one section arc structure of non-uniform gap, and maximum air gap is 1.5: 1 with the minimal air gap ratio; Also have minority to adopt three sections arcs of even air gap or five sections arc structures (not providing the sketch map of this kind pole shoe structure among this report).Though the former air gap flux density Waveform sine is better, the air gap gross area is big and leakage field is big, and the exciting current that needs is big, electric efficiency is low; Though the latter can reduce exciting current, the sine property of air gap flux density waveform is relatively poor.

Summary of the invention

The objective of the invention is to disclose a kind of magnetic pole pole shoe shape of salient pole synchronous electric machine, related position is the pole shoe of salient pole machine rotor magnetic pole, through changing pole shoe shape, reduces leakage field and air-gap mmf, reduces exciting current, reduces the excitation winding temperature rise; Improve air gap flux density waveform and floating voltage waveform, improve the purpose of the quality of power supply, and improve electric efficiency.Technical scheme of the present invention is: a kind of magnetic pole pole shoe of salient pole synchronous electric machine; Magnetic pole is made up of dove tail, excitation winding, pole body and pole shoe and damping winding, and the shape on magnetic pole pole shoe surface is that line segment AB connection line segment BC connects circular arc C D again, and circular arc C D connects line segment DE and connects five sections formations of line segment EF again; The angle of said pole shoe shape line segment BC and AB is the obtuse angle; The chord length of circular arc C D is about 0.9 times of width of pole shoe, and the length of line segment AB and EF is 10mm-20mm, and the angle of line segment DE and EF equals the angle of line segment BC and AB; The radius of circular arc C D is to confirm the definite formula of circular arc C D radius R at 1.35: 1 according to maximum air gap and minimal air gap ratio:

$R=\frac{D_i}{2+\frac{{8D}_i({\mathrm{\δ}}_{\max }-{\mathrm{\δ}}_{\min })}{b_p^2}}\left(\mathrm{cm}\right)$

Wherein: D _i---diameter of stator bore (cm);

δ _Max---maximum air gap length (cm);

δ _Min---minimal air gap length (cm);

b _p---the chord length (cm) of circular arc C D.

The present invention is applicable to salient pole synchronous electric machine, especially is fit to the large-sized water turbine generator field.Pole shoe shape of the present invention not only can make the sine property of air gap flux density waveform good, and voltage-form distortion rate is little, improves the quality of power supply, and the loss that can also reduce power consumption equipment reaches the interference to communication; And because the air gap gross area and polar leakage minimizing etc. can make the exciting current of motor reduce, thereby reduce the excitation winding loss, reduce the excitation winding temperature rise, improve efficiency of motor further.The minimizing of the loss of motor own and the raising of the quality of power supply are the important indicators of high-performance motor.

On the rotor magnetic pole of salient pole synchronous electric machine excitation winding is arranged, wherein is connected with direct current, produce excitation field, in the process of rotor rotation, this magnetic field of stator winding cutting, thus in stator winding induced voltage, accomplish the conversion of mechanical energy to electric energy.The pole shoe shape of distribution situation and the magnetic pole of excitation field in air gap is closely related.The present invention improves the air gap flux density Waveform sine just through changing the shape of pole shoe, reduces the air gap gross area and polar leakage, and exciting current is reduced, and reduces the wastage, and realizes improving the target of the electric efficiency and the quality of power supply.

Adopt the magnetic pole of pole shoe shape of the present invention; Can make exciting current reduce about 3.5%; The air gap flux density Waveform sine is greatly improved, and the loss of high order harmonic component on stator and rotor cores reduced, and therefore can make electric efficiency improve 0.1%; For the hydraulic generator of the vast capacity as Three Gorges, this economic benefit is very huge.In addition, the improvement of air gap flux density waveform sine property can also improve voltage waveform, makes voltage-form distortion rate less than 0.85%, and telephone harmonic form factor improves the quality of power supply greatly less than 0.8%.

Magnetic pole pole shoe of the present invention is one section arc of non-uniform gap and both sides top rake structure; Maximum air gap is 1.35: 1 with the minimal air gap ratio; This pole shoe structure combines the advantage of above-mentioned two kinds of pole shoe structure; Not only reduce exciting current but also guaranteed the sine property of air gap flux density waveform, especially be fit to large-scale generating equipment.

Description of drawings

Fig. 1 has the magnetic pole pole shoe shape now

Fig. 2 magnetic pole pole shoe shape of the present invention

Embodiment:

The magnetic pole pole shoe of a kind of salient pole synchronous electric machine as shown in Figure 2; Magnetic pole is made up of dove tail 1, pole body 2, excitation winding 3 and pole shoe 4 and damping winding 5; The shape on magnetic pole pole shoe surface is that line segment AB connection line segment BC connects circular arc C D again, and circular arc C D connects line segment DE and connects five sections formations of line segment EF again, and the angle of said pole shoe shape line segment BC and AB is the obtuse angle; The chord length of circular arc C D is about 0.9 times of width of pole shoe; The length of line segment AB and EF is 10mm-20mm, and the angle of line segment DE and EF equals the angle of line segment BC and AB, and the radius of circular arc C D is to confirm at 1.35: 1 according to maximum air gap and minimal air gap ratio.

Definite formula of circular arc C D radius R:

$R=\frac{D_i}{2+\frac{{8D}_i({\mathrm{\δ}}_{\max }-{\mathrm{\δ}}_{\min })}{b_p^2}}\left(\mathrm{cm}\right)$

Wherein: D _i---diameter of stator bore (cm);

δ _Max---maximum air gap length (cm);

δ _Min---minimal air gap length (cm);

b _p---the chord length (cm) of circular arc cd.

Claims (1)

1. the magnetic pole pole shoe of a salient pole synchronous electric machine; It is characterized in that: magnetic pole is made up of dove tail (1), pole body (2), excitation winding (3) and pole shoe (4) and damping winding (5), and the shape on magnetic pole pole shoe surface is that line segment AB connection line segment BC connects circular arc C D again, and circular arc C D connects line segment DE and connects five sections formations of line segment EF again; The angle of said pole shoe shape line segment BC and AB is the obtuse angle; The chord length of circular arc C D is about 0.9 times of width of pole shoe, and the length of line segment AB and EF is 10mm-20mm, and the angle of line segment DE and EF equals the angle of line segment BC and AB; The radius of circular arc C D is to confirm the definite formula of circular arc C D radius R at 1.35: 1 according to maximum air gap and minimal air gap ratio:

$R=\frac{D_i}{2+\frac{{8D}_i({\mathrm{\δ}}_{\max }-{\mathrm{\δ}}_{\min })}{b_p^2}}\left(\mathrm{cm}\right)$

Wherein: D _i---diameter of stator bore (cm);

δ _Max---maximum air gap length (cm);

δ _Min---minimal air gap length (cm);

b _p---the chord length (cm) of circular arc C D.

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