CN107659006A - V-shaped groove generator stator core structure - Google Patents

Abstract

The present invention discloses a kind of V-shaped groove generator stator core structure, the tooth head surface (1) of stator core has the groove (2) of v-shaped structure, and the both sides of the groove (2) of v-shaped structure are the arc surface (4) overlapped with stator core inner circle (3).The present invention can change the distribution of the magnetic line of force in stator slot, harmonic wave intensity is set to decrease, reaching reduces the effect of harmonic loss, simultaneously, the structure of V-arrangement can reduce ventilation eddy-current loss, reduce windage, reaching reduces the miscellaneous consumption of generator, improves efficiency, improves generator performance index, improves the purpose of reliability.

Description

V-shaped groove generator stator core structure

Technical field：

The present invention relates to a kind of V-shaped groove generator stator core structure.

Background technology：

Generator stator core, which need to slot, inlays stator winding, because stator core tooth magnetic conductivity is good and groove inner part is led Magnetic difference, the air-gap field of former Sine distribution is set to addition of harmful flutter component, flutter component produces on generator amature surface Raw added losses, it is the important component of generator amature added losses；The phenomenon had both produced loss, declined generator efficiency, Also so that rotor surface heating increase even causes hot-spot, influence generator output and reduce insulation life；Flutter component The key parameters such as the added losses of initiation and generator rated speed, number of stator slots, void dimension are related, and these key parameters Often determined by generator master-plan, be related to the quality of generator techniques parameter so that generator techniques parameter and pulsation The added losses that component triggers are one group of difficult contradiction reconciled：By taking the design of large turbo-type generator as an example, particularly stator slot The less electromagnetic scheme of number, the added losses that flutter component triggers, which exceed, is expected, and reduces the efficiency of generator, and takes increase Number of stator slots or the technical scheme for increasing void dimension, although the loss of flutter component can be reduced, add and are manufactured into This increases excitation loss, also changes alternator performance parameter.

For the problem, magnetic slot-seal is often used on middle and small motor, magnetic slot-seal can increase stator slot oral area The magnetic property of position, it is lost to reduce the amplitude of air gap flutter component, reduce caused by flutter component.But magnetic slot-seal technology Shortcomings：First, although magnetic slot-seal can reduce the amplitude of flutter component in air-gap field, but leakage field point is added Amount, cause other added losses and reduce generator electric property, therefore the selection in magnetic slot-seal magnetic conductivity must be balanced against this and ask Topic, is otherwise difficult to produce a desired effect；Secondly, the selection of magnetic slot-seal and manufacturing technology are still immature, exist after practical application The risk to fall flat, and easily there is machine under the alternate stress effect that the effect of rotor magnetic pull triggers in magnetic slot-seal Tool fatigue, or even occur coming off cause damage generator cella accident；Particularly in terms of large turbo-type generator, magnetic pull is made It is more prominent with problem, so that still there is no applied magnetic slot wedge technology at present；Finally, although large turbo-type generator electromagnetism Load is very high, and structure is extremely compact, but by ventilating and cooling energy power restriction, reduces performance of the added losses to raising generator Index is particularly important, but the utilization of magnetic slot-seal technology is limited the problems such as reliability so that by using magnetic slot-seal technology Improve large turbo-type generator added losses to be difficult to break through.

The content of the invention：It is an object of the invention to provide a kind of V-shaped groove generator stator core structure, improvement gas can be reached The distribution in gap magnetic field, reduce the amplitude of air gap flutter component, reduce the purpose of flutter component loss, can apply in large-scale steamer On generator, stray loss is reduced, the potential safety hazard using magnetic slot-seal will not be brought, loss, the drop of generator can be reduced Low-temperature-rise, generator efficiency is improved, extend generator service life.

The technical scheme is that：A kind of V-shaped groove generator stator core structure, the tooth head surface (1) of stator core There is the groove (2) of v-shaped structure, the both sides of the groove (2) of v-shaped structure are the arc surface (4) overlapped with stator core inner circle (3).

Technique effect：

The technical program is provided with the groove of v-shaped structure in stator tooth head position, and the groove of the v-shaped structure makes tooth head center Missing sites part permeability magnetic material, the magnetic resistance of the position is added, forces the part magnetic line of force at this to be diverted to tooth head both sides position, The magnetic line of force degree of saturation at tooth head both sides position is caused to improve, the magnetic line of force degree of saturation at tooth head both sides position, which improves, can then change The distribution of the magnetic line of force in stator slot, makes the increase of magnetic flux in stator slot；So it is provided with v-shaped structure in stator tooth head position After groove, the magnetic flux distribution of stator tooth head position, stator rabbet position and corresponding air gap can change, i.e. script one Individual complete tooth head magnetic flux crest distribution can split into two magnetic flux crest distributions, play increase stator tooth slot number to a certain extent The effect of amount, in stator slot in the presence of magnetic flux increase, the magnetic flux crest of tooth head position and magnetic flux trough in stator slot Ratio can also reduce, i.e. harmonic wave intensity decreases, and equally also reach the effect for reducing harmonic loss；And the groove of v-shaped structure Both sides be the arc surface overlapped with stator core inner circle, uniform air gap can be formed between rotor surface, also can be with Slide plate forming face contact unshakable in one's determination, reduces pressure, meets the requirement for pulling and pushing rotor holding power, avoids damaging stator core inner surface by pressure； Meanwhile the structure of V-arrangement can make out of stator air duct flow into air gap cooling gas preferably spread, can also make from The cooling gas that air gap enters in stator core air duct is preferably guided, and is reduced ventilation eddy-current loss, is reduced windage, carries High hydro-generator ventilation cooling performance, reduce temperature rise, improve efficiency；The groove for setting v-shaped structure in stator tooth head position also makes original This complete stator tooth head surface becomes two faces, and width diminishes, and the eddy-current loss of stator tooth head surface is decreased；So Technical solution of the present invention, which has reached, to be reduced the amplitude of air gap flutter component using magnetic slot-seal, reduces the effect of flutter component loss Fruit, and the drawbacks of do not bring increase leakage magnetic flux component, also no magnetic slot-seal comes off the potential faults of damage, especially suitable for The Large Copacity or vast capacity steam turbine generator, nuclear power generator of large turbo-type generator, particularly internal water cooling, reach reduction hair The miscellaneous consumption of motor, efficiency is improved, improve generator performance index, improve the purpose of reliability.

Brief description of the drawings：

Fig. 1 is schematic diagram of the present invention.

Fig. 2 is conventional art stator tooth header structure flux pulsation and air gap magnetic line of force distribution schematic diagram.Fig. 3 is skill of the present invention Art scheme air-gap flux is pulsed and magnetic line of force distribution schematic diagram.

Fig. 4 is the present invention and conventional art air gap flux density fluctuating change trend contrast schematic diagram.

Embodiment：The tooth head all surfaces of the stator core of conventional art are the circles overlapped with stator core inner circle Uniform air gap is formed between cambered surface, with rotor surface, can also be contacted with slide plate forming face unshakable in one's determination, reduces pressure, meets branch Support pulls and pushes the requirement of rotor holding power, avoids damaging stator core inner surface by pressure；Because stator core is good by magnetic property Silicon steel sheet is formed, and the stator bar and stator slot wedge in stator slot are all nonmagnetic substances, and stator magnetic flux is concentrated in stator By the way that and the quantity passed through in stator slot is reduced, and equally distributed stator magnetic flux originally is formed with stator tooth, groove in tooth The magnetic flux of regularity of distribution change, as shown in Fig. 2 passing through air gap and rotor surface, rotor will cut arteries and veins relative to stator rotation Dynamic magnetic flux produces vortex, produces and is lost and generates heat；According to calculating and qualitative analysis, it is strong that the size of the loss depends on ripple harmonic Degree, i.e. width and the ratio of air gap value depending on stator tooth head, the width of stator tooth head and the more big then arteries and veins of the ratio of air gap value Dynamic harmonic wave intensity is higher, loss is bigger, and air gap value is determined by generator electromagnetic design and mechanical structure, although increase air gap value can To reduce stray loss, but excitation loss can be also increased, decline generator efficiency, temperature rise improves, or even can not meet maximum Contribute and require；Increase number of stator slots method can only be taken by reducing the width of stator tooth head, but number of stator slots is also dependent on generating electricity The electromagnetic design scheme of machine, for a kind of generator of the specific type of cooling, under certain classical insulation requirement, its Number of stator slots is exactly the numerical value of a determination, it is impossible to is arbitrarily changed, so the numerical value that the width of stator tooth head is just to determine substantially； , should although the purpose that number of stator slots reaches reduction stator tooth head width can be increased using the method for increase parallel branch number Way can increase the dosage of stator bar major insulation, reduce thorax effective rate of utilization in stator, and the increase of the loss brought can be offset The reduction of miscellaneous consumption, does not reach expected purpose；Increased stator bar quantity also increases considerably manufacturing cost, so only Purpose for increase cooling surface area will not generally use this way；The technical program is as shown in figure 1, the tooth of stator core Head surface 1 has the groove 2 of v-shaped structure, and the both sides of the groove 2 of v-shaped structure are the arc surface 4 overlapped with stator core inner circle 3；Should The groove 2 of v-shaped structure makes tooth head centre lack part permeability magnetic material, adds the magnetic resistance of the position, forces part at this The magnetic line of force is diverted to tooth head both sides position, causes the magnetic line of force degree of saturation at tooth head both sides position to improve, tooth head both sides position Magnetic line of force degree of saturation improves the distribution that can then change the magnetic line of force in stator slot, makes the increase of magnetic flux in stator slot；So Stator tooth head position is provided with after the groove 2 of v-shaped structure, stator tooth head position, stator rabbet position and corresponding air gap Magnetic flux distribution can change, as shown in figure 3, i.e. a complete tooth head magnetic flux crest is distributed and can split into two magnetic originally Logical crest distribution, the effect of increase stator tooth slot number amount is played to a certain extent, in stator slot in the presence of magnetic flux increase, The magnetic flux crest of tooth head position can also reduce with the ratio of magnetic flux trough in stator slot, i.e. harmonic wave intensity decreases, equally Reaching reduces the effect of harmonic loss；And the both sides of the groove 2 of v-shaped structure are the arc surfaces overlapped with stator core inner circle, energy It is enough that uniform air gap is formed between rotor surface, it can also be contacted with slide plate forming face unshakable in one's determination, reduce pressure, meet that support is taken out The requirement of rotor holding power is inserted, avoids damaging stator core inner surface by pressure；Meanwhile the structure of V-arrangement can make out of stator air duct The cooling gas for flowing into air gap is preferably spread, and can also make the cooling gas entered from air gap in stator core air duct Preferably guided, reduce ventilation eddy-current loss, reduce windage, improve hydro-generator ventilation cooling performance, reduce temperature rise, improve Efficiency；Setting the groove of v-shaped structure also to make originally in stator tooth head position, completely stator tooth head surface becomes two faces, width Diminish, the eddy-current loss of stator tooth head surface is decreased, reached conventional art and opened narrow slot reduction in side section core tooth head The effect of eddy-current loss, but the core tooth head narrow slot of conventional art can not meet that intensity will due to depth and width ratio limitation Ask, it is necessary to using the measure of bonding, can be only applied to the side iron leg heart, and be unable to reach the effect for changing air-gap field distribution；So Technical solution of the present invention, which has reached, to be reduced the amplitude of air gap flutter component using magnetic slot-seal, reduces the effect of flutter component loss Fruit, and the drawbacks of do not bring increase leakage magnetic flux component, also no magnetic slot-seal comes off the potential faults of damage, especially suitable for The Large Copacity or vast capacity steam turbine generator, nuclear power generator of large turbo-type generator, particularly internal water cooling, reach reduction hair The miscellaneous consumption of motor, efficiency is improved, improve generator performance index, improve the purpose of reliability；Comparison diagram 2 and Fig. 3, it can be seen that The air gap flux density vibration frequency of technical solution of the present invention is two times of conventional art, and fluctuating range decreases, and thus reaches drop The effect of low spurious loss, Fig. 4 is comparison diagram, and A is that air gap waveform, the B of conventional art structure are the air gap ripple of structure of the present invention Shape, it can more intuitively find out the variation tendency of air gap flux density vibration frequency and amplitude；

The present invention need not increase other accessory structures, form generator stator core punching basic structure can with it is past Technology is the same, it is only necessary to the punch die of stator punching is carried out into related change, the tooth head surface 1 of stator punching is formed v-shaped structure Groove 2, the size relationship of the groove 2 of v-shaped structure to miscellaneous consumption reduction degree, the more big then miscellaneous consumption reduction degree of size is also higher, It but the width dimensions of the groove 2 of v-shaped structure can not be excessive, can so cause the arc surface 4 of both sides undersized, be allowed to and iron The contact surface of heart slide plate reduces, and stator core inner surface can be damaged by pulling and pushing pressure caused by rotor, generally use v-shaped structure it is recessed The width dimensions of groove 2 account for the width of whole tooth head 1/2 to 1/3 between it is proper, can access significantly reduces miscellaneous consumption Effect, also disclosure satisfy that requirement of mechanical strength.

Claims (1)

1. a kind of V-shaped groove generator stator core structure, it is characterized in that：The tooth head surface (1) of stator core has the recessed of v-shaped structure Groove (2), the both sides of the groove (2) of v-shaped structure are the arc surface (4) overlapped with stator core inner circle (3).