CN100511931C - Magnetic flux compression pulse straight line generator - Google Patents

Abstract

A flux compressed pulse linear generator utilizes the gas generated from the burning of a propellant to propel the drive piston and further to drive the armature to carry out linear movement for flux compression to generate pulse large current characterizing in separating the drive section and compress section to solve the problem of pollution of the propellant combustion gas to the compress section and the non-conforming design requirement to said two sections.

Description

A kind of magnetic flux compression pulse linear electric generator

Technical field

Magnetic flux compression pulse linear electric generator belongs to the Pulse Power Techniques field.

Background technology

Magnetic flux compression generator is the device that utilizes magnetic field freezing effect principle compression magnetic flux generation high power pulse electric current in the magnetohydrodynamics.

Nineteen forty-two, Alpha has reported magnetic field freezing effect in the magnetohydrodynamics, is conservation by the magnetic flux in any closed-loop path of ideal (conductor fluid) of motion promptly.This conclusion is equally applicable to the good solid conductor of electric conductivity.

The magnetic flux phi that electric current produces in a single turn closed-loop path can be expressed as Φ=LI, wherein L is the inductance in loop, I is the electric current in loop, according to the magnetic confinement equation, (constant) electric current increase under perfect condition if the external force acting reduces inductance, magnetic flux compression generator utilizes this principle that electric current is amplified exactly, is electric energy with other forms of power conversion.

Utilizing electric energy to come the accelerating load device is a development trend of lift-off technology, at aspects such as high-pressure physics experimental technique, aeronautical technology, transportation and thermonuclear fusion technology important application prospects is arranged.Key wherein is a pulse power technology, and it requires the pulse power not only to have high energy storage density, also needs high maneuverability and be easy to reuse.Although obtaining many gratifying achievements aspect the electromagnetic emission research both at home and abroad in recent years, aspect high-power pulse source, still there are many technical problems, limited ELECTROMAGNETIC LAUNCH TECHNOLOGY and moved to maturity and use.

Doctor R.A.Marshall proposed to utilize the burning of propellant to promote armature compresses magnetic flux generation pulse current along the track rectilinear motion contrary railgun magnetic flux compression generator [document 1:R.A.Marshall in 1981, Railgunenergy stores and system, Proceeding of 3 ^RdIEEE International Pulsed PowerConference, June 1981].Fig. 1 is a magnetic flux compression generator theory structure schematic diagram, and it mainly comprises propellant, and one can be along the armature of generating admittance inwall slip, insulation is isolated, and sets up the coil of magnetic flux, steam vent, set up the capacitor group and the switch of seed current, and central conductor leader.Drive section, armature and conducting rod and constitute, at first to the charging of capacitor group, Closing Switch by good conductor, drive section, armature, central conductor leader and inductance coil form the loop and flow through electric current I o, this seed current produces a magnetic field at inductance coil, and can use Φ this moment ₀=L ₀I ₀Calculate the magnetic flux in the inductance coil, be expressed as and the inductance value of inductance coil can be similar to $L={\mathrm{\μ}}_0{N}^2\frac{S}{l},$ Wherein N is a coil turn, and S is a sectional area, and l is a length, square being directly proportional of the inductance value that is to say coil and coil turn.When propellant combustion promotes armature to inductance coil, armature short circuited inductance coil, inductance value reduces, and realizes the amplification of electric current.

Subsequently nearly 20 years, U.S.'s high-tech research the imagination of this power supply has been carried out repeatedly computational analysis and improvement [document 2:R.A.Marshall, The resuable inverse railgun magnetic fluxcompression generator to suit the earth-to space-rail-launch, IEEE Trans.on Mag.vol.20, March 1984; Document 3:R.A.Marshal, IRFC Generators:DesignConsiderations, 3rd European EML Symposium, London 1991; Document 4:R.A.Marshal, The Distributed Energy Store Railgun, Its Effience, and Its Store Implications, IEEE Trans.on Mag.No.1, Janunary 1997], think that rail mounted magnetic flux compression linear electric generator is the ideal source of electromagnetic emission.But this generator inductance gradient is little, and the magnetic flux compression ratio is little, has limited current amplification factor.

The people such as G.G.Kapustjanenko of Ukraine in 1993 propose a kind of coil type magnetic flux compression pulse linear electric motors [document 5:G.G.Kapustjanenko, S.S.Pignasty and S.N.Shevjakin, The LinearElectromechanical generator as Power Source for Rail ElectromagneticLaunchers, 9 ^ThPulsed Power Conference, 1993], he utilizes the magnetic flux in the armature compression inductance coil and produces pulse high current.

It is principle conception [the document 6 Peter Mongeau of the coil type magnetic flux compression linear electric motors of propellant that U.S. Kaman electromagnetism company in 1996 has also provided with diesel oil gas, Combustion Driven Pulsed LinearGenerators for Electric Gun Applications, IEEE Trans.on Mag.Vol.33No.1, Janunary 1997], its operation principle is similar substantially to Fig. 1, different is to have connected a transformer device structure in the coil rear end, is used for the coupling of power output and load.

AUS experimental study chamber and University of Texas's high-tech research support under, three unit consolidations such as doctor's Ed.Goldman leadership system technology and analysis and research group have been developed the reciprocating type magnetic flux compression generator that a kind of heat chemistry big gun of powering uses.[document 7:Edward B.Goldman et al, Development of a FluxCompression Power Unit for Millsecond ETC Pulsed Power Applications, IEEETrans.on Mag.Vol.35, No.1, Janunary 1999].Fig. 2 is a Goldman magnetic flux compression generator structural representation, mainly forms by driving section and compression section, directly connect by flange, and internal diameter equates.Its course of work is as follows: after special armature is accelerated to certain initial velocity by the M256 cannon of 120mm bore, enter in the inductance coil of the uniform pitch of making by stainless steel, at armature with before inductance coil contacts, to the loop charging, in the loop, set up the initial seed electric current by seed excitation power supply (high-voltage energy storage capacitor device group).Document [7] has carried out theoretical simulation to principle model, and simulation result shows: this device can produce the pulse current of electrothermal gun needs, and armature can remain in the loop under the effect of magnetic energy, with the speed correcting action of 3.5m/s.Simultaneously, people such as Ed.Goldman utilize the above-mentioned magnetic flux compression generator of development to carry out experimental study, the result is unsatisfactory, the main cause of analyzing may drive section directly to be connected with the compression section and cause, and exists the matching problem of the armature of high-speed cruising and coil channel and propellant to the pollution problem of coil channel etc.

Because there is resistance in actual system circuit, calculating shows, wants to realize that the amplification of electric current must have bigger inductance gradient, promptly $\frac{\mathrm{dL}}{\mathrm{dt}}\&GreaterEqual;R,$ Wherein R is a loop resistance.Want to satisfy the energy loss that this critical condition should reduce loop resistance as far as possible and brought, should improve the variation inductance rate simultaneously.Know from top analysis, $L={\mathrm{\&mu;}}_0{N}^2\frac{S}{l}={\mathrm{\&mu;}}_0{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="C200310100173E00091.png,C200310100173E00092.png"\; state="\{\{state\}\}">n</figure-callout>}}^2\mathrm{Sl},$ Wherein n is the unit length coil turn, then $\frac{\mathrm{dL}}{\mathrm{dt}}={\mathrm{\&mu;}}_0{n}^{2}S\frac{\mathrm{dl}}{\mathrm{dt}}={\mathrm{\&mu;}}_0{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="C200310100173E00091.png,C200310100173E00092.png"\; state="\{\{state\}\}">n</figure-callout>}}^2\mathrm{Sv},$ Wherein v is an armature speed.Theoretically, under the certain situation of physical dimension, the speed that improves armature is unusual valid approach, yet the problem that runs in the actual engineering design is the restriction that armature speed is activated mode, and armature at a high speed is very difficult with cooperating of coil.

The existence of the problems referred to above has influenced the conversion of this technology of piston type magnetic flux compression generator from notion to application.

Summary of the invention

At the problem that above-mentioned prior art exists, the present invention proposes a kind of novel magnetic flux compression linear electric generator, and its feature is to have solved pollution and the influence of propellant to power channel, and the inductance gradient is big, and current amplification factor is big, and technical being easy to realized.

Basic structure of the present invention comprises 3 parts, drives section, accelerating sections and compression section.Drive section and separate, between driving section and compression section, accelerating sections is housed, drive section, accelerating sections and compression section three parts and adopt flange to be connected with the compression section.Drive section by propellant, driven plunger, connecting rod, steam vent, insulating barrier, buffer spring constitutes, and driven plunger and connecting rod are rigidly connected, with a driving section urceolus tight fit.Steam vent is positioned at the afterbody that drives section, is used for relieving pressure, and buffer spring is positioned at the bottom that drives section, is used to cushion the piston system of high-speed motion.Armature is positioned at accelerating sections, is rigidly connected with driven plunger, and the compression section is made of inductance coil and composite insulating material, and its internal diameter is identical with accelerating sections, and armature can slide in accelerating sections and compression section.

The course of work of the present invention is as follows: driven plunger is in original position.Light propellant during work, propellant combustion produces high-temperature high-pressure fuel gas and makes that driving the section internal pressure sharply rises, promote driven plunger to previous crops accelerated motion, drive with the rigidly connected armature of piston and in accelerating sections, quicken, this moment Closing Switch, the capacitor group is by the coil of compression section, load, central conductor leader, armature and accelerating sections metal outer wall form the loop, flow through initial current I0, in the inductance coil of compression section, form magnetic flux Φ, armature enters the compression section and contacts with the inductance coil that initial current is arranged after reaching certain speed, this moment, the capacitor group was disconnected, inductance coil, central conductor leader, load forms the loop, along with the motion short circuited inductance of armature carries out the magnetic flux compression, realize the amplification of electric current.In the course of work, driven plunger, armature system are when being subjected to burning gases thrust, and armature also is subjected to Ampere force, and driven plunger stops after buffer spring drives piston, armature system slowdown.

Characteristics of the present invention are:

1. drive section and separate, be connected by accelerating sections with the compression section.This design can improve winding inductance quantity by increasing the compression section diameter, makes compression process obtain bigger inductance gradient, inductance rate of change and current amplification factor;

2. avoided the erosion of propellant and burning gases to the compression section, solved the technical barrier that driving section and compression section structural strength are difficult to mate simultaneously, main consideration combustion characteristics and mechanical strength in the design that drives section, and in the design of compression section, mainly consider current characteristics and electrically contact problem.

3. solved and promptly be damaged or contaminated shortcoming after prior art makes compression section work once, reusable.

Description of drawings

Fig. 1 is the magnetic flux compression generator principle assumption diagram, among the figure: 1 propellant, 2 armatures, 3 insulating material, 4 inductance coils, 5 composite insulating materials, 6 steam vents, 7 capacitor groups, 8 switches, 9 central conductor leaders, 10 drive section;

Fig. 2 is a prior art Goldman magnetic flux compression generator structure chart, among the figure: 1 propellant, 2 armatures, 4 inductance coils, 9 central conductor leaders, 11 strutting pieces, 12 coil support, 13 end caps, 14 urceolus;

Fig. 3 is a specific embodiment of the invention structural representation, among the figure: 1 propellant, 2 armatures, 3 insulating material, 4 inductance coils, 5 composite insulating materials, 6 steam vents, 7 capacitor groups, 8 switches, 9 central conductor leaders, 15 driven plunger, 16 connecting rods, 17 insulating barriers, 18 loads, 19 bracing frames, 20 buffer springs;

Fig. 4 is a compression section of the present invention schematic diagram, among the figure: 4 inductance coils, 21 flanges, 22 insulation are supported, and 23 central conductor leaders support;

Fig. 5 is an armature structure schematic diagram of the present invention, among the figure: 9 central conductor leaders, 16 connecting rods, 24 springs, 25 contact slippers, 26 armature bodies.

Embodiment

Describe content of the present invention in detail below in conjunction with drawings and the specific embodiments.

Referring to accompanying drawing 3: driving section of the present invention adopts metal material, and for example stainless steel cylinder is made, and adopts flange to be connected with accelerating sections.Drive section by propellant 1, driven plunger 15, connecting rod 16, steam vent 6, insulating barrier 17, buffer spring 20 constitutes.Driven plunger 15 is in driving section, and employing connecting rod 16 is rigidly connected between the armature in accelerating sections 2, with a driving section urceolus tight fit.Connecting rod 16 adopts metal material, and for example stainless steel is made.Steam vent is used for relieving pressure at the afterbody that drives section, and buffer spring 20 is used to cushion the piston system of high-speed motion in the bottom that drives section.Accelerating sections is by metal material, and for example red copper is made.The compression section by metal material for example copper and insulating material for example the inductance coil 4 that processes of glass cloth constitute, internal diameter is identical with the accelerating sections internal diameter, accelerating sections adopts flange to be connected with the compression section on the right.One end of central conductor leader 9 extend in armature 2 centre bores, and the other end is fixed on the end of accelerating sections, and driven plunger 15 is being with connecting rod 16 and armature to slide along central conductor leader 9.Switch 8, capacitor group 7 is used to provide initial current.Bracing frame 19 is used for supporting generator system, guarantees to drive section, accelerating sections, compression section three's center on same horizontal axis.

The course of work of the present invention is as follows: light propellant 1 in driving section, propellant 1 burning produces high-temperature high-pressure fuel gas and makes that driving the section internal pressure sharply rises, promote driven plunger 15 to previous crops accelerated motion, drive with driven plunger 15 rigidly connected armatures 2 and in accelerating sections, quicken, the motion of armature 2 is except the thrust that is subjected to propellant 1 burning and is provided, also be compressed the various resistances that resistance that the rear end air produced and electric current move and produced in magnetic field, before armature 2 enters the compression section and inductance coil 4 contacts, give by inductance coil 4 with outside small-power DC power supply, the series circuit that load 18 and central conductor leader 9 are formed provides seed current I ₀, in the loop, set up the seed magnetic flux.After armature 2 enters the compression section and inductance coil 4 contacts, driven plunger 15 moves forward under the promotion of combustion gas, and armature 2 keeps continuous electric to contact with inductance coil 4, and the coil turn of armature 2 back is thrown out of current circuit, along with travelling forward of armature 2, the inductance in the loop constantly reduces.Ideally, because magnetic flux conservation in good conductor, promptly the product of inductance and electric current remains unchanged, and inductance reduces, and electric current must increase, and will obtain amplified current in the load 18.Driven plunger 15 stops after buffer spring 20 slows down.In this process, armature is gone through acceleration, deceleration and static three kinds of motion states.

Fig. 4 is a compression section of the present invention schematic diagram.Referring to accompanying drawing 4, inductance coil 4 adopts copper column type material, beats positioning through hole in the axis and two end flanges are installed.Inductance coil 4 is formed by the whole car system of metal material, its manufacture method is: twine the thick epoxy cloth of 10-20mm outside car is made externally threaded copper coin cylinder, and between screw thread closely knit filling epoxy cloth, get through the hole at the cylinder central shaft then, the car interior diameter is to the screw thread place, constitute screwed pipe shape inductance coil, its turn-to-turn has the insulation of epoxy cloth to support.According to through-current capability and the outer cutting thread of insulating requirements, the electric current lead-out wire is installed.Because inductance coil not only will bear big electric current, also will bear big turn-to-turn voltage, therefore to guarantee the sectional area of inductance coil.

Fig. 5 is an armature structure schematic diagram of the present invention.Referring to accompanying drawing 5, armature body 26 adopts metal material, for example aluminium is made, contact slipper 25 adopts metal material, and for example copper becomes, along armature body 26 axially even distribute 6 or 8 holes, be used for mounting spring 24 and contact slipper 25, spring 24 and contact slipper 25 adopts welding manners to be connected, and contact slipper 25 constitutes slip rings, guarantees that armature 2 is after moving to the compression section and be positioned at the excellent electric contact of the inductance coil 4 of compression section.

The driving section of the specific embodiment of the invention is made of stainless steel cylinder, 82 millimeters of internal diameters, can be according to concrete rate request design internal diameter between the 80mm to 500mm, the heavy 7kg of driven plunger, armature, connecting rod and center conductive lever system, accelerating sections is made of red copper, long 1m, internal diameter requires to change at 100mm to 1000mm according to output, and armature enters compression section initial velocity 300m/s, the long 600mm of coil, internal diameter 160mm, winding wire cross section 12mm ², insulation thickness 3mm, the inductance number of turn 100, inductance value $L={\mathrm{\&mu;}}_0{N}^2\frac{S}{l}=420\mathrm{\&mu;H},$ The remaining inductance in loop after the compression is 2uH, and the loop adopts the bigger good conductor of conductivity loop resistance can be controlled in the 60m Ω.

Connecting rod between piston and the armature is that stainless steel material is made.The present invention need can be applicable to the occasion of pulse high current.

Claims (3)

1, a kind of magnetic flux compression pulse linear electric generator comprises driving section and compression section, it is characterized in that driving section and separates with the compression section, between driving section and compression section accelerating sections is housed, and drives section, accelerating sections and compression section three parts and adopts flange to be connected; The internal diameter of accelerating sections and compression section equates, armature [2] is positioned at accelerating sections, be rigidly connected by connecting rod [16] with driven plunger [15], accelerating sections and central conductor leader [9] are made by metal material, central conductor leader [9] one ends extend in the armature centre bore, the other end is fixed on the end of accelerating sections, and connecting rod by the driven plunger band and armature slides along central conductor leader.

2, magnetic flux compression pulse linear electric generator as claimed in claim 1 is characterized in that said compression section is by flange [21], and [22] are supported in insulation, and inductance coil [4] and central conductor leader support [23] and form; Inductance coil [4] is formed by the whole car system of metal material, its manufacture method is: twine the thick epoxy cloth of 10-20mm outside car is made externally threaded copper coin cylinder, and between screw thread closely knit filling epoxy cloth, get through the hole at the cylinder central shaft then, the interior diameter car is to the screw thread place, constitute screwed pipe shape inductance coil, its turn-to-turn has the insulation of epoxy cloth to support.

3, magnetic flux compression pulse linear electric generator as claimed in claim 1, it is characterized in that said armature is by armature body [26], spring [24], contact slipper [25] is formed, spring [24] adopts welding manner to be connected with contact slipper [25], constitute slip ring by contact slipper [25], assurance armature [2] is realized excellent electric contact with the inductance coil [4] that is positioned at the compression section after moving to the compression section.

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