CN105448389B - Low-impedance high-voltage coaxial cable - Google Patents

Abstract

The invention relates to a low-impedance high-voltage coaxial cable belonging to the technical field of pulse power. The invention is composed of N metal inner conductors, N inner insulating layers, a metal outer conductor, an outer insulating layer and metal connectors; N is more than or equal to 2; the N metal inner conductors and the N inner insulating layers form N high voltage wires; the N high voltage wires are arranged into n layers in the outer insulating layer; n is more than or equal to 2; the N inner insulating layers are mutually independent; the N metal inner conductors are respectively connected parallelly at two ends through two metal connectors so as to form the inner conductor of the low-impedance high-voltage coaxial cable; the N mutually independent inner insulating layers form the inner insulating layer of the low-impedance high-voltage coaxial cable; the outer insulating layer and the metal outer conductor are taken as the outer insulating layer and the outer conductor of the low-impedance high-voltage coaxial cable. Because the N high-voltage wires are connected parallelly, the impedance and the usage amount of the metal inner conductor are reduced, the problem of high turn radius resulted from directly increasing the diameters of the inner conductor and the outer conductor in the traditional low-impedance high-voltage coaxial cable is solved.

Description

A kind of low impedance, high voltage coaxial cable

Technical field

The present invention relates to a kind of low impedance, high voltage coaxial cable is and in particular to a kind of high voltage, tight-turning low-resistance Anti- coaxial cable, belongs to technical field of pulse power, is mainly used in pulse signal transmission and the generation of high-voltage square-wave pulse.

Background technology

In technical field of pulse power, high-pressure coaxial cable can be used for transferring high voltage pulse it is also possible to make pulse-forming line, For producing high-voltage square-wave pulse.Through the development of decades, high-pressure coaxial cable running voltage is promoted to number from tens kilovolts Hundred kilovolts, it has been applied in various types of pulse power device, such as line transformer, solid state pulse manipulator Deng.However, as the high-pressure coaxial cable of these devices, presently, there are the problems such as impedance is higher, radius of turn is big, device is made to hinder Anti- higher, volume more huge it would be highly desirable to solve.

Traditional high-pressure coaxial cable is typically by metallic inner conductor, inner insulating layer, metal outer conductor and external insulation layer four Divide layer overlaps to form, by adjusting the diameter of metallic inner conductor, inner insulating layer and metal outer conductor, coaxial cable can be adjusted Running voltage and impedance, in general, inner insulating layer is thinner, and running voltage is lower, and impedance is less.And it is certain in order to ensure Running voltage, in order to reduce impedance, needs to increase the diameter of metallic inner conductor, inner insulating layer and metal outer conductor simultaneously, causes High-pressure coaxial cable volume is larger, and radius of turn also larger [Chen Guoping, Luo Yi, " and the preparation of low-impedance coaxial cable with can Adjust the resis tance method of surveying ", digital communication, 2014, vol.41, no.6, pp.1-2].

Low impedance, high voltage coaxial cable generally existing on market is relatively large in diameter, and the larger problem of radius of turn is it is impossible to expire The demand of sufficient densification high power pulse power device, therefore, searching diameter is little, the little low impedance, high voltage coaxial electrical of radius of turn Cable is significant to the densification of high power pulse power device.

Content of the invention

The technical problem to be solved in the present invention is to overcome existing low impedance, high voltage coaxial cable to be relatively large in diameter, and radius of turn is relatively Wait greatly not enough it is proposed that one kind is by the parallel connection of multiply metallic inner conductor, the detached new low impedance, high voltage coaxial cable of inner insulating layer, It has structure simply, high pressure, and impedance is low, the little advantage of radius of turn.

The technical solution used in the present invention is:

A kind of Low ESR high voltage coaxial cable, by n root metallic inner conductor, n bar inner insulating layer, metal outer conductor, outer absolutely Edge layer and metal connector composition, n >=2, n root metallic inner conductor and n bar inner insulating layer constitute n root high-tension bus-bar, n root high-tension electricity Line is in that n-layer arranges in external insulation layer, n >=2, and n bar inner insulating layer is separate, and n root metallic inner conductor passes through respectively at two ends Two pieces of metal connectors are connected in parallel, and constitute the inner wire of Low ESR high voltage coaxial cable, the separate interior insulation of n bar Layer constitutes the inner insulating layer of low impedance, high voltage coaxial cable, and external insulation layer and metal outer conductor are as low impedance, high voltage coaxial cable External insulation layer and outer conductor；

For ensureing high-voltage resistance capability, Low ESR and the tight turn radius of Low ESR high voltage coaxial cable of the present invention, Need fully to design the size of each building block of low impedance, high voltage coaxial cable, need to consider following two aspects in design:

1. in low impedance, high voltage coaxial cable n root metallic inner conductor diameter d₁, the diameter d of n bar inner insulating layer₂, n root gold Largest outer diameter (the d being formed after belonging to inner wire arrangement_k+d₁) and metal outer conductor interior diameter d_iSelection to disclosure satisfy that in spy Will not puncture under fixed working voltage, meetWherein e_bFor inner insulating layer insulation The disruptive field intensity of material, is determined by the insulation characterisitic of insulant, v_cFor the running voltage of coaxial cable, k is to puncture safe system Number, 0 < k < 1, k is less, is less susceptible to puncture；

2. the impedance required for low impedance, high voltage coaxial cable is by the interior diameter d of metal outer conductor_i, metal outer conductor outer Diameter d_wDetermine, in general cable resistance is with the radical n of high-tension bus-barL is the electricity of cable unit length Sense, c is the electric capacity of cable unit length, and the circular of l and c is as follows:

Calculate l and c when, coaxial cable is respectively labeled as from inside to outside the 1st layer, the 2nd layer, the 3rd layer ..., until N-th layer, in general, high-tension bus-bar quantity n is bigger, and number of plies n is more, and wherein the 1st layer is made up of 1 high-tension bus-bar, with metal Outer conductor constitutes coaxial configuration；2nd layer is made up of i root high-tension bus-bar, the circumference that the metallic inner conductor center of i root high-voltage line surrounds A diameter of d₃；3rd layer is made up of j root high-tension bus-bar, and the circle diameter that the metallic inner conductor center of j root high-voltage line surrounds is d₄；……；N-th layer is made up of k root high-tension bus-bar, and the circle diameter that the metallic inner conductor center of k root high-voltage line surrounds is d_k, that The 1st layer of inductance constituting coaxial configuration with metal outer conductor can be calculated be respectively as follows: with electric capacity

$l_1=\frac{{\mathrm{\&mu;}}_0{\mathrm{\&mu;}}_r}{2\mathrm{\&pi;}}ln(d_i/d_1),c_1=\frac{2{\mathrm{\&pi;\&epsiv;}}_0{\mathrm{\&epsiv;}}_r}{ln(d_i/d_1)}---\left(1\right)$

Wherein μ₀For permeability of vacuum, ε₀For permittivity of vacuum, μ_rFor the relative permeability of insulating barrier insulant, ε_r For the relative dielectric constant of insulating barrier insulant, the 2nd layer of inductance being constituted with metal outer conductor is respectively as follows: with electric capacity

$\begin{array}{c}{l}_2=\frac{{\mathrm{\&mu;}}_0{\mathrm{\&mu;}}_r}{2\mathrm{\&pi;}}\&lsqb;\ln \left(\frac{d_i}{d_3}\right)+\frac{1}{3}\frac{d_w-d_i}{d_i}(1-\frac{1}{10}\frac{{(d_w-d_i)}^2}{{d_i}^2})+\frac{1}{4i}+\frac{1}{i}\ln \left(\frac{d_3}{i\&times;d_1}\right)\&rsqb;\\ c_2=\frac{2{\mathrm{\&pi;\&epsiv;}}_0{\mathrm{\&epsiv;}}_{r}i}{\ln (d_i/d_1)}\&lsqb;1-{\left(\frac{d_3}{d_1}\right)}^2\frac{5{(d_i/d_1)}^2-1}{8\&lsqb;{(d_i/d_1)}^2\&rsqb;\ln (d_i/d_1)}-{\left(\frac{d_3}{d_1}\right)}^4\frac{9{(d_i/d_1)}^4-1}{128\&lsqb;{(d_i/d_1)}^8-{(d_i/d_1)}^2\&rsqb;\ln (d_i/d_1)}\&rsqb;\end{array}---\left(2\right)$

The 3rd layer of inductance being constituted with metal outer conductor is respectively as follows: with electric capacity

$\begin{array}{c}{l}_3=\frac{{\mathrm{\&mu;}}_0{\mathrm{\&mu;}}_r}{2\mathrm{\&pi;}}\&lsqb;ln\left(\frac{d_i}{d_4}\right)+\frac{1}{3}\frac{d_w-d_i}{d_i}(1-\frac{1}{10}\frac{{(d_w-d_i)}^2}{{d_i}^2})+\frac{1}{4i}+\frac{1}{i}ln\left(\frac{d_4}{i\&times;d_1}\right)\&rsqb;\\ c_3=\frac{2{\mathrm{\&pi;\&epsiv;}}_0{\mathrm{\&epsiv;}}_{r}j}{\ln (d_i/d_1)}\&lsqb;1-{\left(\frac{d_4}{d_1}\right)}^2\frac{5{(d_i/d_1)}^2-1}{8\&lsqb;{(d_i/d_1)}^4-{(d_i/d_1)}^2\&rsqb;\ln (d_i/d_1)}-{\left(\frac{d_4}{d_1}\right)}^4\frac{9{(d_i/d_1)}^4-1}{128\&lsqb;{(d_i/d_1)}^8-{(d_i/d_1)}^4\&rsqb;\ln (d_i/d_1)}\&rsqb;\end{array}---\left(3\right)$

……

The inductance that n-th layer is constituted with metal outer conductor and electric capacity are respectively as follows:

$\begin{array}{c}{l}_n=\frac{{\mathrm{\&mu;}}_0{\mathrm{\&mu;}}_r}{2\mathrm{\&pi;}}\&lsqb;ln\left(\frac{d_i}{d_k}\right)+\frac{1}{3}\frac{d_w-d_i}{d_i}(1-\frac{1}{10}\frac{{(d_w-d_i)}^2}{{d_i}^2})+\frac{1}{4i}+\frac{1}{i}ln\left(\frac{d_k}{i\&times;d_1}\right)\&rsqb;\\ c_n=\frac{2{\mathrm{\&pi;\&epsiv;}}_0{\mathrm{\&epsiv;}}_{r}k}{\ln (d_i/d_1)}\&lsqb;1-{\left(\frac{d_k}{d_1}\right)}^2\frac{5{(d_i/d_1)}^2-1}{8\&lsqb;{(d_i/d_1)}^4-{(d_i/d_1)}^2\&rsqb;\ln (d_i/d_1)}-{\left(\frac{d_k}{d_1}\right)}^4\frac{9{(d_i/d_1)}^4-1}{128\&lsqb;{(d_i/d_1)}^8-{(d_i/d_1)}^4\&rsqb;\ln (d_i/d_1)}\&rsqb;\end{array}---\left(4\right)$

Therefore entirely the unit length inductance of coaxial cable is respectively as follows: with capacitance per unit length

$l=\frac{1}{\frac{1}{l_1}+\frac{1}{l_2}+\frac{1}{l_3}+...+\frac{1}{l_n}}---\left(5\right)$

C=c₁+c₂+c₃+…+c_n

Further, in order to improve the high-voltage resistance capability of coaxial cable of the present invention, can be between n root high-tension bus-bar Corresponding insulant is filled, such as transformer oil, politef etc. between gap.

Further, the inner insulating layer of coaxial cable of the present invention is politef.

Further, the metal outer conductor of coaxial cable of the present invention is wire sheathing.

Further, the external insulation layer of coaxial cable of the present invention is politef.

The operation principle of the present invention is: theoretical according to coaxial cable, metallic inner conductor, inner insulating layer, metal outer conductor and External insulation layer four part layer overlaps just constitute coaxial cable.Traditional metallic inner conductor and inner insulating layer are carried out by the present invention Improve, be changed to n bar high-tension bus-bar in parallel, such that it is able to reduce the impedance of coaxial cable, the radius of turn of reduction coaxial cable.By Can ensure that in this structure and lead outside the running voltage of coaxial cable, and quantity n by reasonable selection high-tension bus-bar and metal The diameter of body just can conveniently adjust the impedance of coaxial cable, meets compact, the application need of miniaturization high power pulse device Ask.

Compared with prior art, it is an advantage of the invention that by the parallel connection of n bar high-tension bus-bar, increasing in coaxial cable metal The diameter of conductor, thus reducing impedance, simultaneously because the n bar high-tension bus-bar adopting is in parallel, reduces metallic inner conductor Usage amount, it is to avoid traditional low impedance, high voltage coaxial cable directly increases internal and external conductor diameter and leads to the big problem of radius of turn.

Brief description

Fig. 1 is background technology [Chen Guoping, Luo Yi, " preparation of low-impedance coaxial cable and adjustable resistance method of testing ", number Word communicate, 2014, vol.41, no.6, pp.1-2] in conventional coaxial cable generalized section；

Fig. 2 is the low impedance, high voltage coaxial cable tomograph of the present invention；

Fig. 3 is the sectional view of the single high-tension bus-bar forming low impedance, high voltage coaxial cable of the present invention；

Fig. 4 is the low impedance, high voltage coaxial cable sectional view of the present invention；

Fig. 5 is the sectional view of the low impedance, high voltage coaxial cable designs example of the present invention；

Fig. 6 is the experiment test of low impedance, high voltage coaxial cable designs example and the simulation calculation waveform of the present invention；

Wherein 9 is experiment test waveform, and 10 is simulation calculation waveform.

Specific embodiment

Below in conjunction with the accompanying drawings the specific embodiment of the present invention is further described.

Fig. 1 is background technology [Chen Guoping, Luo Yi, " preparation of low-impedance coaxial cable and adjustable resistance method of testing ", number Word communicate, 2014, vol.41, no.6, pp.1-2] in conventional coaxial cable generalized section, from figure as can be seen that tradition Coaxial cable mainly by single piece of metal inner wire 1, inner insulating layer 2, metal outer conductor 3 and external insulation layer 4 form, in order to meet work Make the demand of voltage, need when reducing impedance to increase metallic inner conductor 1, inner insulating layer 2, metal outer conductor 3 and external insulation layer 4 Diameter, cause high-pressure coaxial cable radius of turn larger.

Fig. 2 is Low ESR high voltage coaxial cable tomograph of the present invention, and the Low ESR high voltage of the present invention is same Shaft cable is made up of high-tension bus-bar 5, metal outer conductor 6, external insulation layer 7 and metal clutch disk 8, every high-tension bus-bar 5 by Individually metallic inner conductor 501 and inner insulating layer 502 form, and metallic inner conductor 501 is connected by metal respectively two ends Disk 8 is in parallel.

Fig. 3 is the sectional view of the high-tension bus-bar 5 forming low impedance, high voltage coaxial cable of the present invention, described high-tension bus-bar 5 are made up of metallic inner conductor 501 and inner insulating layer 502, by the diameter d of reasonable selection metallic inner conductor 501₁And inner insulating layer 502 diameter d₂, high-tension bus-bar 5 can be made to be operated in specific voltage.

Fig. 4 is low impedance, high voltage coaxial cable sectional view of the present invention.The radical n of high-tension bus-bar, arranges as n-layer, and the 1st Layer is made up of 1 high-tension bus-bar, and it constitutes coaxial configuration with metal outer conductor；2nd layer is made up of i root high-tension bus-bar, i root high pressure The circle diameter that the metallic inner conductor center of line surrounds is d₃；3rd layer by j root high-tension bus-bar, the metallic inner conductor of j root high-voltage line The circle diameter that center surrounds is d₄；……；N-th layer is made up of k root high-tension bus-bar, in the metallic inner conductor of k root high-tension bus-bar The circle diameter that the heart surrounds is d_k；High-pressure coaxial cable metal outer conductor interior diameter d_i, the overall diameter d of metal outer conductor_w, coaxially Largest outer diameter d of cable_a；

The sectional view of the low impedance, high voltage coaxial cable that Fig. 5 designs for the National University of Defense technology.The design work of this coaxial cable Making voltage is 50kv, impedance 10 ω.The radical n=19 of high-tension bus-bar, point 3 layers of arrangement, high-tension bus-bar interior diameter d₁=0.4mm, Overall diameter d₂=4mm；The circle diameter that the metallic inner conductor center of the 2nd layer of 6 high-tension bus-bar surrounds is d₃=8mm；3rd layer 12 The circle diameter that the metallic inner conductor center of root high-tension bus-bar surrounds is d₄=16mm；Straight in high-pressure coaxial cable metal outer conductor Footpath d_i=20mm, the overall diameter d of metal outer conductor_w=21mm；Largest outer diameter d of coaxial cable_a=22mm, insulant is adopted With politef, its relative dielectric constant ε_r=2.3, according toAnd formula (1)-(5) calculate inductance and electricity The method held, the design impedance that can obtain cable is about 10 ohm.

Fig. 6 is the test experiments waveform of low impedance, high voltage coaxial cable designs example and the simulation calculation waveform of the present invention (in figure 9 is experimental waveform, and 10 is simulation waveform).Method using experiment and simulation comparison measures coax impedance, will be with Shaft cable is used as pulse and forms line, and load impedance is taken 50 ohm.By the pulse shaping function of coaxial cable, test Voltage waveform in load, resettles circuit simulating software, sets load impedance as 50 ohm, adjusts the resistance of coaxial cable Anti-, when simulation waveform is consistent with experimental waveform, the impedance of coaxial cable can be obtained, about 10 ohm, with design objective one Cause.

More than, provide description of the invention to those skilled in the art, so that they should be readily appreciated that and prevaricate this Invention.For those skilled in the art, the various changes that these are implemented are even more it will be apparent that and need not be creative Work.Therefore, the present invention is not to limit scheme described herein, but the scope consistent with described claim.

Claims (6)

1. a kind of Low ESR high voltage coaxial cable it is characterised in that: described coaxial cable by n root metallic inner conductor, n bar absolutely Edge layer, metal outer conductor, external insulation layer and metal connector composition, n >=2, n root metallic inner conductor and n bar inner insulating layer constitute n Root high-tension bus-bar, n root high-tension bus-bar is in that n-layer arranges in external insulation layer, n >=2, and n bar inner insulating layer is separate, n root metal Inner wire is connected in parallel by two pieces of metal connectors respectively at two ends, constitutes in Low ESR high voltage coaxial cable and leads Body, the separate inner insulating layer of n bar constitutes inner insulating layer, external insulation layer and the metal outer conductor of low impedance, high voltage coaxial cable External insulation layer as low impedance, high voltage coaxial cable and outer conductor；

The circular of the electric capacity c of the inductance l of the unit length of described coaxial cable and unit length is as follows:

Coaxial cable is respectively labeled as from inside to outside the 1st layer, the 2nd layer, the 3rd layer ..., until n-th layer, in general, high Piezoelectric wire quantity n is bigger, and number of plies n is more, and wherein the 1st layer is made up of 1 high-tension bus-bar, constitutes coaxial knot with metal outer conductor Structure；2nd layer is made up of i root high-tension bus-bar, and the circle diameter that the metallic inner conductor center of i root high-voltage line surrounds is d₃；3rd layer by J root high-tension bus-bar forms, and the circle diameter that the metallic inner conductor center of j root high-voltage line surrounds is d₄；……；N-th layer is high by k root Piezoelectric wire forms, and the circle diameter that the metallic inner conductor center of k root high-voltage line surrounds is d_k, then the 1st layer can be calculated The inductance constituting coaxial configuration with metal outer conductor is respectively as follows: with electric capacity

Wherein μ₀For permeability of vacuum, ε₀For permittivity of vacuum, μ_rFor the relative permeability of insulating barrier insulant, ε_rFor insulation The relative dielectric constant of layer insulant；

The 2nd layer of inductance being constituted with metal outer conductor is respectively as follows: with electric capacity

The 3rd layer of inductance being constituted with metal outer conductor is respectively as follows: with electric capacity

The inductance that n-th layer is constituted with metal outer conductor and electric capacity are respectively as follows:

Therefore entirely the inductance of unit length of coaxial cable is respectively as follows: with the electric capacity of unit length

C=c₁+c₂+c₃+…+c_n._.

2. according to claim 1 Low ESR high voltage coaxial cable it is characterised in that: in order to improve described coaxial cable High-voltage resistance capability, can between the gap of n root high-tension bus-bar fill insulant.

3. according to claim 2 Low ESR high voltage coaxial cable it is characterised in that: described insulant be transformer oil Or politef.

4. according to claim 1 Low ESR high voltage coaxial cable it is characterised in that: described inner insulating layer be polytetrafluoroethyl-ne Alkene.

5. according to claim 1 Low ESR high voltage coaxial cable it is characterised in that: described metal outer conductor be metal compile Tissue layer.

6. according to claim 1 Low ESR high voltage coaxial cable it is characterised in that: described external insulation layer be polytetrafluoroethyl-ne Alkene.