CN1767316A - Mixed excitation synchronous motor with radial structure - Google Patents

Abstract

The invention relates to a radial structure mixed exciter synchronic motor which comprises: a stator formed by armature core 2 inside the casing 1 and the armature coil group 3 and a rotor formed by rotating shaft 11, rotor core 10, N-pole permanent magnet 4 and S-pole permanent magnet 6; the radial structure permanent magnet synchronic motor is formed by the stator and the rotor; the N-pole permanent magnet and the S-pole permanent magnet of the rotor are separately adhered 5 and 7 and makes the N-pole annex magnet and the S-pole annex magnet to extent with the same direction. The extent part of the rotor arranges an exciting coil group 9 and a ring-type exciting magnetic bridge 8.

Description

Mixed excitation synchronous motor with radial structure

One, technical field

The present invention relates to a kind of hybrid exciting synchronous motor.

Two, technical background

Permagnetic synchronous motor has been eliminated the excitation loss of electric excitation synchronous motor with permanent magnet excitation, and has eliminated the Mechanical Contact device, has remarkable advantage simple in structure, reliable and that power density is big, efficient is high.But the intrinsic permanent magnetic field of magneto is regulated difficulty has become the bottleneck that it is used and promote aspect generator and adjustable-speed motor.Existing permanent magnet has excitation winding again in the hybrid exciting synchronous motor, two magnetic potential sources exist simultaneously, combine advantages such as the convenient and permagnetic synchronous motor efficient height of electric excitation synchronous motor adjustable magnetic, torque/mass ratio are big, overcome simultaneously permagnetic synchronous motor magnetic field again and regulated difficult defective, had broad application prospects at many industrial circles and military fields such as Aero-Space, naval vessel.

The B.A. Б а л а г у р о в of Moscow aeronautical engineering institute professor proposed the structure of magnetic potential mixed excitation synchronous generator in parallel in 1988.Stator is identical with common synchronous machine, and rotor is divided into two parts, and a part is a permanent magnet excitation, and another part is electric excitation.The electric excitation division of this motor is divided into claw-pole structure, and additional air gap is many, axial magnetic circuit, and leakage field is big, and electric excitation function is restricted.

The nineties in last century, Japanese doctor T.Mizuno has proposed rotor Splittable hybrid exciting synchronous motor.The stator armature winding of this motor is common three-phase symmetric winding, and stator core is divided into two sections by stator ring DC excitation winding, and this two iron legs heart mechanically with on the magnetic is connected by its outer back of the body yoke (casing that is used for axial magnetic conduction); Rotor is separated into two parts also: N is extreme and S is extreme, and every interpole that is extremely formed by same polarity permanent-magnet pole and iron core is staggered, and the N at two ends, S permanent-magnet pole and interpole also are staggered.One solid flux sleeve letter (rotor back of the body yoke) is arranged between rotor core and rotating shaft, be used for the axial magnetic conduction of rotor, have the axial/radial magnetic circuit, electric machine structure optimization is tied, and field ampere-turns is bigger.

Professor Lipo of Wisconsin-Madison university waits and has proposed a kind of axial magnetic field rotor Splittable hybrid exciting synchronous motor structure.It is made of the annular stator core (wherein being embedded with the polyphase armature winding) of two flutings, two disk rotors, a DC excitation winding.At the rotor surface interpole that permanent-magnet pole and iron core form that is being staggered.This motor adds that the stator and rotor iron core all is divided into two sections owing to adopted interpole, and additional air gap is many, and required field ampere-turns is big.

The old clear spring of Hong Kong University, professor Jiang Jianzhong of Shanghai Polytechnic Univ etc. have proposed a kind of Lundell hybrid exciting synchronous motor.The external stator of this motor and the stator of common electric machine are similar, are embedded with heterogeneous symmetric winding in the groove, and rotor adopts claw-pole structure, places permanent magnet between two adjacent pawl utmost points.Because the DC excitation winding places in the formed zone, inside and outside unit by the pawl utmost point, space availability ratio height, compact conformation.But owing to there is axial magnetic circuit, electric excitation efficiency is low.

Three, summary of the invention

The objective of the invention is at above-mentioned the deficiencies in the prior art, provide a kind of simple in structure, the mixed excitation synchronous motor with radial structure that electric excitation efficiency is high with permanent magnet magnetic shunt.

The formation of mixed excitation synchronous motor with radial structure of the present invention is on the basis of radial structure permagnetic synchronous motor, placement tile shape magnetic conductor is close in every utmost point permanent magnet outside on the rotor core outer surface more respectively, will extend to same direction vertically corresponding to the tile shape magnetic conductor of the N utmost point and the S utmost point.Stationary annular magnetic conduction bridge is arranged between the magnetic conductor extension, the two poles of the earth, and the embedding of excitation control winding is around in the annular magnetic bridge.Armature winding on the stator is identical with the armature winding structure of common permagnetic synchronous motor.

This mixed excitation synchronous motor with radial structure is as follows, the stator be made up of armature core and armature winding is housed in casing and the rotor core of rotor shaft is housed and radial tile N utmost point permanent magnet and S utmost point permanent magnet are formed places the radial structure synchronous machine that rotor constituted in the stator, the N utmost point permanent magnet outside that is characterized at rotor is glued with tile shape N utmost point additional guide magnet, the S utmost point permanent magnet outside is glued with tile shape S utmost point additional guide magnet, N utmost point additional guide magnet and S utmost point additional guide magnet extend to same direction vertically, the N utmost point (or S utmost point) additional guide magnet is horn-like expansion, assembles the bigger hollow cylinder N utmost point (or the S utmost point) annular magnetizer of internal diameter; The S utmost point or N utmost point magnetic conductor are the bottleneck shape and shrink, and assemble the less hollow cylinder S utmost point (or the N utmost point) annular magnetizer of external diameter.Be placed with the annular magnetic conduction bridge of embedding between the hollow cylinder magnetic conductor of the two poles of the earth magnetic conductor elongated end around excitation winding.

This mixed excitation synchronous motor with radial structure has following characteristics:

1. overcome the shortcoming that the permagnetic synchronous motor air gap flux density is difficult to regulate, can regulate air gap flux density easily by exciting current.

2. can control the adjustable range of air-gap field by the ratio of adjusting electric excitation and permanent magnetism part rotor length and main air gap and additional gas length.

When 3. not having exciting current in the magnet exciting coil, motor is compared with common radial structure permagnetic synchronous motor and is in weak magnetic state, and air gap flux density is little.Along with exciting current increases, the corresponding increase of air gap flux density.

4. air-gap flux is not that exciting current magnetic field is set up, and mainly is to be generated by the radial magnetizing permanent magnetism body, and having avoided exciting current to set up air-gap field needs the big shortcoming of field ampere-turns, and less field ampere-turns just can obtain the wide range regulation of air-gap field.

5. compare with rotor Splittable hybrid exciting synchronous motor, the axial magnetic circuit of motor significantly shortens, and volume, the size of motor are little, simple in structure.

When 6. this hybrid exciting synchronous motor is as brushless AC generator, compare, saved exciter and rotating rectifier, thereby simplify electric machine structure, improved functional reliability with three grades of formula rotating rectifier formula no-brush synchronous generators.

When 7. motor is made electric operation, can work in two zones of permanent torque and permanent power, the wide ranges of Heng Gongshuaiqu and controlled.

Four, description of drawings

Fig. 1 is 2 pairs of utmost point mixed excitation synchronous motor with radial structure structural representations.

Fig. 2 is rotor part A-A sectional view among Fig. 1.

Fig. 3 is the additional guide magnet and the extension structure chart thereof of rotor.

Above-mentioned number in the figure title: 1, casing; 2, armature core; 3, armature winding; 4, N utmost point permanent magnet; 5, N utmost point additional guide magnet and extension thereof; 6, S utmost point permanent magnet; 7, S utmost point additional guide magnet and extension thereof; 8, annular magnetic bridge; 9, excitation winding; 10, rotor core; 11, rotating shaft.

Fig. 4 is a mixed excitation synchronous motor with radial structure equivalent magnetic circuit schematic diagram.

Designation among Fig. 4: R _{δ N}The air-gap reluctance that-N is extremely relative; R _{δ S}The air-gap reluctance that-S is extremely relative; R _A-armature tooth portion and yoke portion magnetic resistance; R _PMN-N utmost point permanent magnet magnetic resistance; R _PMS-S utmost point permanent magnet magnetic resistance; R _{δ 11}-N the utmost point extends additional air-gap reluctance between magnetic conductor and annular magnetic bridge; R _{δ 12}-annular the magnetic bridge and the S utmost point extend additional air-gap reluctance between magnetic conductor; R _FE-annular magnetic bridge magnetic resistance; U _N-N utmost point permanent magnet magnetic potential; U _S-S utmost point permanent magnet magnetic potential.

Five, embodiment

By Fig. 1, Fig. 2 and Fig. 3 as can be known, the composition of mixed excitation synchronous motor with radial structure of the present invention is, the magnetic conductor that closely links to each other by the radial structure permagnetic synchronous motor and with its rotor surface permanent magnet and the electric excitation division of a side are grouped into.Promptly the stator of forming by armature winding 3, armature core 2 and rotating shaft 11 is housed and the basis of the radial structure permagnetic synchronous motor that rotor constituted formed by rotor core 10 and the surface-type N utmost point and S utmost point permanent magnet 4 and 6 on, all be close to a tile shape additional guide magnet 5 and 7 in the outside of each utmost point surface permanent magnetic body of rotor, extend to same direction vertically corresponding to the additional guide magnet of N utmost point permanent magnet with corresponding to the additional guide magnet of S utmost point permanent magnet.As shown in figures 1 and 3, the N utmost point (or S utmost point) additional guide magnet is horn-like expansion, assembles the bigger hollow cylinder N utmost point (or the S utmost point) magnetic guiding loop of internal diameter; Correspondingly the S utmost point (or N utmost point) additional guide magnet is the contraction of bottleneck shape, assembles the less hollow cylinder S utmost point (or the N utmost point) magnetic guiding loop of external diameter.On the additional guide magnet magnet isolation tank can be set, to reduce the quadrature axis armature reaction reactance.Be placed with between the cylindrical magnetic conductor of the two poles of the earth magnetic conductor elongated end can embedding around the annular magnetic conduction bridge 8 of excitation winding 9.Said structure all is loaded in the casing 1, and casing is common hardware.

The operation principle of mixed excitation synchronous motor with radial structure:

A. mixed excitation synchronous motor with radial structure of the present invention is owing to the magnetic shunt effect of annular magnetic bridge, additional guide magnet and additional air gap, and magnetic field of permanent magnet provides radial flux and axial magnetic flux simultaneously.The radial flux path is: N utmost point magnet → main air gap → stator teeth and yoke portion → main air gap → S utmost point magnet → rotor core → N utmost point magnet; The axial magnetic flux path is: N utmost point magnet → N utmost point additional guide magnet and extension thereof → additional air gap → annular magnetic bridge → additional air gap → S utmost point additional guide magnet and extension → S utmost point magnet → rotor core → N utmost point magnet thereof.

When the excitation winding in the annular magnetic bridge did not have exciting current, because additional air gap is less with respect to main air gap, magnetic field of permanent magnet mainly provided axial magnetic flux, and motor is in weak magnetic state.

When excitation winding fed a certain direction exciting current, excitation field can hinder the axial magnetic flux that permanent magnet produces, thereby increases main air-gap flux; When excitation winding feeds in the other direction electric current, can further weak magnetic, be zero until air-gap flux.

B. mixed excitation synchronous motor with radial structure both can be used as generator, also can be used as motor.Can analyze the operation principle of this motor according to equivalent magnetic circuit shown in Figure 4.

The air-gap reluctance that N is extremely relative is labeled as R _{δ N}The air-gap reluctance that S is extremely relative is labeled as R _{δ S}Magnetic resistance such as the armature tooth portion that will connect with main air gap and yoke are labeled as R _AThe magnetic resistance of N utmost point permanent magnet is labeled as R _PMN, the magnetic resistance of S utmost point permanent magnet is labeled as R _PMSThe magnetic potential that N utmost point permanent magnet provides is U _N, the magnetic potential that S utmost point permanent magnet provides is U _SThe magnetic resistance that extends additional air gap between magnetic conductor 1 and annular magnetic bridge is labeled as R _{δ 11}, the magnetic resistance of annular magnetic bridge and 2 additional air gaps of extension magnetic conductor is labeled as R _{δ 12}The magnetic resistance of annular magnetic bridge is labeled as R _FE

Generally speaking, R _{δ N}=R _{δ S}=R _δR _PMN=R _PMS=R _PM

During the excitation winding excitation-free current, excitation magnetic potential does not exist.Can derive the air gap main flux from equivalent magnetic circuit is:

${\mathrm{\Φ}}_S=\frac{R_{\mathrm{\δ}11}+R_{\mathrm{FE}}+R_{\mathrm{\δ}12}}{({2R}_{\mathrm{\δ}}+R_A)(R_{\mathrm{\δ}11}+R_{\mathrm{FE}}+R_{\mathrm{\δ}12})+{2R}_{\mathrm{PM}}({2R}_{\mathrm{\δ}}+R_A+R_{\mathrm{\δ}11}+R_{\mathrm{FE}}+R_{\mathrm{\δ}12})}\×(U_N+U_S)$

$=\frac{1}{({2R}_{\mathrm{\δ}}+R_A)+{2R}_{\mathrm{PM}}+\frac{{2R}_{\mathrm{PM}}({2R}_{\mathrm{\δ}}+R_A)}{R_{\mathrm{\δ}11}+R_{\mathrm{FE}}+R_{\mathrm{\δ}12}}}\×(U_N+U_S)$

By electromagnetism knowledge, with respect to air-gap reluctance, R _AAnd R _FEIt is less,

R in addition _{δ 12}＜R _{δ 11}＜＜R _δ＜＜R _PMSo:

$\frac{{2R}_{\mathrm{pm}}({2R}_{\mathrm{\δ}}+R_A)}{R_{\mathrm{\δ}11}+R_{\mathrm{FE}}+R_{\mathrm{\δ}12}}>>1$

As seen, during excitation-free current, since the effect of magnetic shunt, main air-gap flux Φ _sLess, motor is in weak magnetic state.

When feeding exciting current in the excitation winding, the required excitation magnetic potential value of permanent magnetic potential in the magnetic shunt is offset in derivation fully below.

Excitation magnetic potential is offset the permanent magnetic potential in the magnetic shunt fully, and then permanent magnet flux is all by main air gap.

${\mathrm{\Φ}}_S=\frac{U_N{+U}_S}{{2R}_{\mathrm{PM}}+{2R}_{\mathrm{\δ}}+R_A}$

So required excitation magnetic potential is

$U_F=\frac{{2R}_{\mathrm{\δ}}+R_A}{{2R}_{\mathrm{PM}}+{2R}_{\mathrm{\δ}}+R_A}\×(U_N+U_S)$

As seen, exciting current is done the time spent, and less excitation magnetic potential just can be offset the magnetic shunt effect, and controlling main air-gap flux increases.That is to say that less excitation magnetic potential just can be realized the wide range regulation to main air-gap flux.

Suitably design the physical dimension of motor, can be so that R _PM, R _δAnd R _FERational numerical is arranged, thereby change the power of air-gap field under the weak magnetic state, change the power that exciting current can be controlled air-gap field effectively.

The advantage of mixed excitation synchronous motor with radial structure,

1. overcome the shortcoming that common Air-gap Flux Density in Permanent Magnet Machines is difficult to regulate, can transfer easily by exciting current Air gap magnetic is close.

2. the adjustable range of air-gap field can by adjust electric excitation and permanent magnetism part rotor length and main air gap with The ratio of additional air gap length is controlled, the design of electrical motor requirement of the different performance that is content with very little.

3. when not adding excitation, the magnetic field under the main pole is in weak magnetic state, reduces the possibility that permanent magnet is demagnetized. Exciting current is done the time spent, has hindered the magnetic flux of additional air gap, the magnetic flux of main air gap is increased, and plays to increase magnetic Effect. Field ampere-turns required when regulating air-gap field is much smaller compared with the common electrical excitation magnetic synchronization motor, Reduced excitation loss, more energy-conservation.

4. because annular magnetic bridge and electric excitation division divide a side that arranges with the permanent magnetism part, so that the axial magnetic circuit of motor ratio Rotor Splittable hybrid exciting synchronous motor shortens, and can reduce volume, the size of motor, and is simple in structure.

5. both can be used as generator and also can make motor. As generator, excitation is adjustable, and compares electric excitation Brushless AC motor has been saved exciter and rotating rectifier, greatly simplifies electric machine structure; As motor, Can work in permanent power and Heng Zhuanjuqu, permanent power bracket is wide and controlled.

Claims (2)

1. mixed excitation synchronous motor with radial structure, be included in the rotor core (10) of the stator of being made up of armature core (2) and armature winding (3) being housed in the casing (1) and rotating shaft (11) being housed, and diametrical magnetization N utmost point permanent magnet (4) and S utmost point permanent magnet (6) form place the radial structure synchronous machine that rotor constituted in the stator, it is characterized in that: N utmost point additional guide magnet and extension (5) thereof in axial direction are close in the outside that also is included in the N utmost point permanent magnet (4) of rotor, in axial direction be close to S utmost point additional guide magnet and extension (7) thereof in the outside of S utmost point permanent magnet (6), the bearing of trend of the two poles of the earth additional guide magnet is identical, and the hollow cylinder magnetic conductor space between N utmost point additional guide magnet elongated end and S utmost point additional guide magnet elongated end is provided with the circular excitation magnetic bridge (8) of embedding around excitation winding (9).

2. mixed excitation synchronous motor with radial structure according to claim 1, it is characterized in that, the N utmost point or S utmost point additional guide magnet elongated end are horn-like expansion, assemble the bigger hollow cylinder N utmost point of internal diameter or S polar ring shape magnetic conductor, correspondingly the S utmost point or N utmost point additional guide magnet elongated end are the contraction of bottleneck shape, assemble external diameter than the former the less hollow cylinder S utmost point or N polar ring shape magnetic conductor.

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