CN201594495U - Bistable permanent magnet mechanism capable of reducing switching and tripping current - Google Patents

Abstract

The invention relates to a bistable permanent magnet mechanism capable of reducing the switching and tripping current. The permanent magnet mechanism comprises a static iron core (1), a movable iron core (3), a switching coil (2), a tripping coil (5), ring-shaped permanent magnets (4), magnetic-conductive sleeves (7) and a drive rod (6); a magnetic-conductive rib (8) is arranged on the inner side of the middle part of the static iron core (1) and divides the static iron core (1) into to two chambers; the switching coil (2) and the tripping coil (5) are respectively arranged in the two chambers; the ring-shaped permanent magnets (4) are respectively arranged on the inner sides of the two end surfaces of the static iron core (1); the magnetic-conductive sleeves (7) are arranged on the inner sides of the ring-shaped permanent magnets (4); the drive rod (6) connected with the magnetic-conductive sleeves in a sliding manner is arranged in inner holes of the magnetic-conductive sleeves; the movable iron core (3) is fixed on the outer side of the drive rod (6); and a space allowing the movable iron core to move is left between end caps of the movable iron core (3) and the static iron core (1). The permanent magnet mechanism can reduce the switching and tripping current remarkably under the condition of outputting the same electromagnetic force.

Description

Can reduce the bistable-state permanent magnet mechanism of on/off switch electric current

Technical field

The present invention relates to a kind of bistable-state permanent magnet mechanism of parallel circuits structure, belong to switchgear manufacturing technology field in the electro-engineering.

Background technology

Traditional operating mechanism that is applicable to vacuum circuit-breaker can be divided into two kinds of electromagnetic operating mechanism and spring operating mechanisms.Simple in structure, the low cost of manufacture of electromagnetic operating mechanism, but the electromagnetic operating mechanism closing operation needs DC power supply that very big operating current was provided in the short time, and electromagnetic operating mechanism need keep the snap close of closing position.Spring operating mechanism is with the energy storage of AC/DC low-power machine, and the small-power tripping coil carries out breaking-closing operating, and is very little to the capacity requirement of power supply, do not have impulse current substantially, but the spring mechanism number of spare parts is more, has unreliable factor.

Along with the continuous development of vacuum circuit-breaker in middle pressure field, and the raising day by day of permanent magnetic material performance, permanent-magnet manipulating mechanism has more and more caused people's attention.Permanent-magnet manipulating mechanism is a kind of dependence solenoid suction branch, combined floodgate, and a kind of novel mechanism that permanent-magnet keeps because the permanent-magnet manipulating mechanism part is few, simple in structure, develops over more than 10 year rapidly in release.But, the on/off switch operation of permanent magnet mechanism, particularly closing operation necessary operations electric current is still bigger, this makes that the investment on DC power supply device greatly increases in the transformer substation construction, and the on/off switch of the big electric current of permanent magnet mechanism operation also reduced the reliability of DC power system, and this may be that the permanent magnet mechanism large tracts of land is promoted the use of the main cause that suffers from difficulty.

At present, rise to national strategy along with building intelligent grid strong, high flexible, the reliability of raising vacuum circuit-breaker, the demand of controllability become more urgent.Therefore, reforming the operating mechanism of vacuum circuit-breaker, further improve the performance of permanent magnet mechanism, promote the application of permanent magnet mechanism in intelligent vacuum circuit-breaker, is an important goal of switch industry.

At present common bistable-state permanent magnet mechanism as shown in Figure 1, it is made up of static iron core 1, moving iron core 3, closing coil 2, switching winding 5 and the permanent magnet 4 that is positioned at the middle part.The combined floodgate of this bistable-state permanent magnet mechanism (or separating brake) coil and permanent magnet form the series circuit structure, owing in the magnetic circuit of (or separating brake) coil that closes a floodgate, be in series with permanent magnet, and the magnetic permeability of permanent magnet is very low, its magnetic permeability approaches permeability of vacuum, therefore, combined floodgate (or separating brake) magnetic potential that coil produced mainly drops on working gas gap and the permanent magnet.As seen, the bigger magnetic potential of the combined floodgate of the permanent magnet mechanism of series circuit structure (or separating brake) action need is to overcome the magnetic circuit process potential drop that permanent magnet was produced.Because the bigger magnetic potential of traditional permanent magnet mechanism on/off switch action need, if the coil turn of permanent magnet mechanism is fixed, then DC power supply need provide bigger short-term operation electric current, causes the direct current system investment to increase, and reliability reduces.Therefore, design that a kind of on/off switch electric current permanent-magnet manipulating mechanism little, that dynamic response is fast has and the significance of reality.

Summary of the invention

Technical problem: the objective of the invention is to: the bistable-state permanent magnet mechanism on/off switch electric current at traditional series circuit is big, the situation that on/off switch operation reliably is difficult to guarantee, a kind of bistable-state permanent magnet mechanism that reduces the on/off switch electric current is provided, under the condition of the equal electromagnetic force of output, can significantly reduce the on/off switch electric current.

Technical scheme: the object of the present invention is achieved like this: this permanent magnet mechanism comprises static iron core, moving iron core, closing coil, switching winding, annular permanent magnet, flux sleeve and drive rod; Be provided with the magnetic conduction muscle in the inboard at static iron core middle part static iron core is divided into two intervals, in two intervals closing coil and switching winding are set respectively, in end face inboard, described static iron core two ends one annular permanent magnet is set respectively, in described annular permanent magnet inboard flux sleeve is set, the drive rod that is slidingly connected mutually with described flux sleeve is set in the endoporus of flux sleeve, the fixing moving iron core in the outside of described drive rod leaves the space that moving iron core moves between moving iron core and the static iron core end cap.

The cross section of described moving iron core and static iron core contact-making surface is the frustum shape that matches; The static iron core end is the boss shape, and relative therewith moving iron core end is a recess.The magnetic circuit of described closing coil and switching winding and the magnetic path parallel connection of permanent magnet.The contact-making surface of described moving iron core and static iron core end face can adopt the sloping platform shape of differing heights at switching winding end and closing coil end.

Described static iron core, moving iron core and flux sleeve adopt permeability magnetic material to make, and drive rod adopts non-magnet material.

Beneficial effect: the invention has the advantages that: annular permanent magnet is fixed in the end face inboard of static iron core, there is not permanent magnet in the path, magnetic field that closing coil or switching winding excitation are produced, the magnetic circuit of permanent magnetic circuit and coil is in parallel, because the magnetic permeability of permanent magnet approaches the magnetic permeability of air, therefore coil magnetic circuit is parallel to permanent magnetic circuit, make the magnetic resistance on the coil magnetic circuit greatly reduce, and then reduction closing coil or the required excitation magnetic potential of switching winding, under the situation of identical coil turn, can effectively reduce the operating current of permanent magnet mechanism, reduce permanent magnet mechanism to DC power supply at capacity with export requirement aspect the short time current, guarantee that permanent magnet mechanism can reliably working, and can suitably reduce the investment of transformer station aspect DC power supply.Static iron core and moving core ends adopt the contact-making surface of sloping platform shape, can under the certain situation of static iron core wall thickness, effectively increase the sectional area of permanent magnet, thereby permanent magnetic field is enhanced, increase the confining force of permanent magnet in combined floodgate or separating brake position, and can be according to the design needs of permanent magnet mechanism, rationally adjust the height of close a floodgate end or separating brake end sloping platform shape, obtain suitable closing position permanent magnetism confining force and separating brake position permanent magnetism confining force respectively.Coil magnetic circuit is mainly by moving the inclined-plane of iron core and static iron core sloping platform shape contact-making surface, under moving iron core and the constant situation of static iron core slide relative distance, gas length in the coil magnetic circuit reduces to some extent, long-pending the obtaining of the cross-section of air gap increases, according to the electromagnetism principle as can be known, moving iron core can be under the prerequisite that obtains identical switching force or separating brake power with the oblique contact-making surface of static iron core in the coil magnetic circuit, further reduce the on/off switch electric current, also can be under the prerequisite that does not reduce the on/off switch electric current, improve the initial velocity of on/off switch operation, improve the dynamic property of permanent magnet mechanism, thereby improve the combination property of vacuum circuit-breaker.

Description of drawings

Fig. 1 is a series circuit bistable-state permanent magnet mechanism sectional view;

Fig. 2 is a parallel circuits bistable-state permanent magnet mechanism sectional view;

Fig. 3 is the magnetic circuit schematic diagram of parallel circuits bistable-state permanent magnet mechanism;

Fig. 4 is moving iron core and the oblique contact-making surface schematic diagram of static iron core, and wherein Fig. 4 (a) is the contact-making surface magnetic line of force; Fig. 4 (b) is the size of contact-making surface.

Have among the figure: static iron core 1, closing coil 2, moving iron core 3, permanent magnet 4, switching winding 5, drive rod 6, flux sleeve 7, magnetic conduction muscle 8, permanent magnetic circuit 9, closing coil magnetic circuit 10, air gap 11, the magnetic line of force 12.A is the magnetic circuit shortest path length on the moving relative static iron core of iron core inclined-plane, and x is the iron core width.

Embodiment

Accompanying drawing discloses the concrete structure of the embodiment of the invention without limitation, and the invention will be further described below in conjunction with accompanying drawing.

As seen from Figure 2, can reduce the bistable-state permanent magnet mechanism of on/off switch electric current, comprise moving iron core, static iron core, coil and permanent magnet, the magnetic conduction muscle at static iron core middle part is divided into two intervals with static iron core, in two intervals closing coil and switching winding are set respectively, in static iron core end face inboard annular permanent magnet is set, in the annular permanent magnet inboard flux sleeve is set, the drive rod that is slidingly connected mutually with flux sleeve is set in the endoporus of flux sleeve, fixing moving iron core on drive rod leaves the space that moving iron core moves between moving iron core and the static iron core end cap.The contact-making surface of moving iron core and static iron core end face is set to the sloping platform shape, and the static iron core end is a boss shape, and relative therewith moving iron core end is depression shape, and permanent magnet is installed on the plane of static iron core boss, and the permanent magnet two ends are concordant with the surfaces externally and internally of static iron core boss.

As seen from Figure 3, permanent magnetic circuit and closing coil magnetic path parallel connection mainly pass the inclined-plane of sloping platform at air gap place coil magnetic circuit.In coil magnetic circuit, do not have permanent magnet, under the certain condition of the mobile space between static iron core and the moving iron core, thereby can effectively reduce the on/off switch electric current that the needed total magnetic potential of coil magnetic circuit reduces permanent magnet mechanism.By Fig. 4 (a) as seen, when static iron core and moving iron core were contact-making surface with 45 inclined-planes, the magnetic line of force was sentenced shortest path perpendicular to the inclined-plane by air gap at air gap, at the air gap two ends since the edge effect magnetic circuit can prolong to some extent.By Fig. 4 (b) as seen, when the relative static iron core movable distance of moving iron core be

The time, the magnetic circuit shortest path length on inclined-plane is amm, when moving iron core and static iron core when being straight plane contact shown in dotted line the iron core movable distance equal air-gap magnetic circuit length, it is constant suppose that the electromagnetic attraction of iron core direction is moved in maintenance, then has following relational expression

$F=\frac{1}{\sqrt{2}}\frac{{10}^7}{8\mathrm{\π}}{B}^{\′2}{S}^{\′}=\frac{{10}^7}{8\mathrm{\π}}{B}^{2}S---\left(1\right)$

F is the electromagnetic attraction component along moving iron core moving direction in the formula; B ' and S ' are respectively inclined-plane gap density and contact area; B and S are respectively and face gap density and contact area directly.Can get by Fig. 4 (b)

$S^{\′}=\sqrt{2}S---\left(2\right)$

Wushu (2) substitution formula (1) can get

B＝B′ (3)

If ignore the iron core potential drop, then the combined floodgate of parallel circuits permanent magnet mechanism or switching winding excitation magnetic potential all drops on the air gap, and the magnetic circuit of facing contact-making surface so directly satisfies

$\mathrm{NI}=H\sqrt{2}a=\frac{B}{{\mathrm{\μ}}_0}\sqrt{2}a---\left(4\right)$

N is a coil turn in the formula; I is for facing contact-making surface situation lower coil exciting curent directly; H is for facing air-gap field intensity directly; μ ₀Be permeability of vacuum.The magnetic circuit of inclined-plane contact-making surface satisfies

${\mathrm{NI}}^{\′}=H^{\′}\mathrm{ka}=\frac{B^{\′}}{{\mathrm{\μ}}_0}\mathrm{ka}---\left(5\right)$

I ' is an inclined-plane contact-making surface situation lower coil exciting curent in the formula; H ' is an inclined-plane air-gap field intensity; K is a prolongation coefficient of considering edge effect inclined-plane magnetic circuit path, gets that to prolong coefficient k be 1.1, can be got by formula (3) and comparison expression (4) and formula (5) so

$I^{\&prime;}=\frac{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="HSA00000032280800011.png,HSA00000032280800012.png"\; state="\{\{state\}\}">k</figure-callout>}}{\sqrt{2}}\&CenterDot;\frac{B}{{\mathrm{\&mu;}}_0}\sqrt{2}a=\frac{\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="HSA00000032280800011.png,HSA00000032280800012.png"\; state="\{\{state\}\}">k</figure-callout>}}{\sqrt{2}}\&CenterDot;I=0.78I---\left(6\right)$

This shows, after the parallel circuits bistable-state permanent magnet mechanism adopts sloping platform shape contact-making surface, can further reduce the electric current of closing coil or switching winding, also can be under same current, obtain bigger electromagnetic attraction, thereby increase permanent magnet mechanism initial motion speed, improve the dynamic response performance of permanent magnet mechanism.

Claims (3)

1. the bistable-state permanent magnet mechanism that can reduce the on/off switch electric current is characterized in that this permanent magnet mechanism comprises static iron core (1), moving iron core (3), closing coil (2), switching winding (5), annular permanent magnet (4), flux sleeve (7) and drive rod (6); Be provided with magnetic conduction muscle (8) in the inboard at static iron core (1) middle part static iron core (1) is divided into two intervals, closing coil (2) and switching winding (5) are set respectively in two intervals, in end face inboard, described static iron core (1) two ends one annular permanent magnet (4) is set respectively, in described annular permanent magnet (4) inboard flux sleeve (7) is set, the drive rod (6) that is slidingly connected mutually with described flux sleeve is set in the endoporus of flux sleeve (7), the fixing moving iron core (3) in the outside of described drive rod (6) leaves the space that moving iron core moves between moving iron core (3) and static iron core (1) end cap.

2. the bistable-state permanent magnet mechanism that reduces the on/off switch electric current according to claim 1 is characterized in that the described moving iron core (3) and the cross section of static iron core (1) contact-making surface are the frustum shape that matches; Static iron core (1) end is the boss shape, and relative therewith moving iron core (3) end is recess.

3. the bistable-state permanent magnet mechanism that reduces the on/off switch electric current according to claim 1 and 2 is characterized in that the magnetic circuit of described closing coil (2) and switching winding (5) and the magnetic path parallel connection of permanent magnet (4).

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