CN102769406B - A connection structure of ring series loading line - Google Patents

Abstract

The invention relates to a connection structure of an annular series loading line, comprising an annular series loading line, a plexiglass support cylinder, a grounding support, and an outer cylinder; it is characterized in that it also includes a tapered paper cylinder and a copper mesh; the connection between the annular series loading line and the outer There is a cone-shaped paper tube between the tubes, and copper mesh is wound on the cone-shaped paper tube. The small-diameter end of the cone-shaped paper tube is connected to the lowest stage of the annular series loading line, and the large-diameter end is connected to the outer cylinder. Since the size of the additional inductance when the loading lines are connected in series depends on the area enclosed by the internal and external discharge channels during discharge, the tapered grounding cylinder of the present invention changes the external discharge channel, thereby reducing the area enclosed by the internal and external discharge channels during discharge , can significantly reduce the additional inductance of the load line series structure and improve its high frequency performance. Therefore, the output voltage waveform of this loading line series structure is better.

Description

A connection structure of ring series loading line

technical field

The invention belongs to the technical field of pulse power, and relates to a connection structure of ring-shaped series loading lines, which is a series structure of loading lines of high-power microwave driving sources for generating long pulses.

Background technique

In order to study the generation of high-power long-pulse electron beams, it is necessary to develop high-power long-pulse source-related technologies. At present, the high-voltage long pulse generation device mainly adopts several fast pulse forming technologies such as pulse forming network (PFN), helical pulse line (Helical Forming Line) or composite medium forming line with high dielectric constant, and PFN is used in generating hundreds of nanosecond pulses. Compared with the other two technologies, the technology has advantages in terms of device volume weight and implementation difficulty.

[Title] A Long-Pulse Generator Based on Tesla Transformer and Pulse-FormingNetwork. Su J.C., Zhang X.B. IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL.37, NO.10, OCT.2009:1954-1958, disclosed a capacitor The Tesla-PFN type long pulse power source connected to the loading plate line after the forming line. [Title] Structural Design of Tesla-PFN Type Long Pulse Power Source Loading Line (Li Rui, Zhang Xibo, Su Jiancang. Intense Laser and Particle Beams, 2011, 23 (11): 2893-2896), published Tesla-PFN type long pulse power source The specific structure of the series connection of multiple capacitively loaded double-conductor planar transmission lines of the pulse power source. In order to improve the working voltage, when the above-mentioned loading lines are used in series, on the one hand, the pulse propagation direction is the same after series connection, which will cause problems such as shortened pulse width, reduced impedance and waveform degradation. When the number of series series increases, these problems will become It is particularly prominent and not easy to solve; on the other hand, no matter what structure the series loading line adopts, there will be an additional inductance. The additional inductance depends on the number and structure of the series series. The existence of the additional inductance will affect the high frequency response of the loading line. And as the number of series connection increases, the high-frequency characteristics will be worse, which will affect the output pulse quality.

Contents of the invention

In order to avoid the deficiencies of the prior art, the present invention proposes a connection structure of ring-shaped series loading lines to solve the problem of mutual electromagnetic interference when the Tesla-PFN type long pulse drive source capacitively loads flat plate lines in series and discharges them, and reduces the loading line The additional inductance of the series structure improves the flatness of the output pulse top of the series loaded line.

A connection structure of a ring-shaped series loading line, including a ring-shaped series loading line 4, a plexiglass support cylinder 9, a ground support 8, and an outer cylinder 7; it is characterized in that it also includes a tapered paper tube 5 and a copper mesh 6; A cone-shaped paper tube 5 is arranged between the wire 4 and the outer cylinder 7, and a copper mesh 6 is wound on the cone-shaped paper tube 5. It is connected with the outer cylinder 7; the shielding ring at the front end is removed from the ring-shaped series loading line 4 .

The diameter of the small end of the tapered paper tube 5 is the same as the outer diameter of the annular series loading line 4 , and the diameter of the larger end is the same as the inner diameter of the outer cylinder 7 .

The connection structure of a ring-shaped series loading line proposed by the present invention, on the one hand, because the pulse propagation direction is opposite when the adjacent loading line is discharged, the induced current caused by the mutual inductance is opposite to the conduction current direction of the plate, which can just offset the loop to a certain extent. Due to the tendency of the output current to increase due to the decrease of the impedance along the angular direction of the loading line, the total output current tends to be stable, and it has good demagnetic coupling characteristics. On the other hand, since the size of the additional inductance when the loading line is connected in series depends on the area enclosed by the inner and outer discharge channels during discharge, the tapered grounding cylinder changes the outer discharge channel, thereby reducing the area enclosed by the inner and outer discharge channels during discharge. The area can significantly reduce the additional inductance of the load line series structure and improve its high frequency performance. Therefore, the output voltage waveform of this loading line series structure is better.

Description of drawings

Figure 1: It is a schematic diagram of the overall structure of the series loading line;

Figure 2: It is a schematic diagram of the structure of a single-stage capacitively loaded double-conductor flat plate transmission line;

Figure 3: It is a schematic diagram of the series structure of multi-stage loading lines connected in reverse;

1-capacitor bank, 2-double conductor plate, 3-electrical cardboard, 4-ring loading line, 5-conical paper tube, 6-copper mesh, 7-outer tube, 8-ground support, 9-plexiglass support tube , 10-screw.

Detailed ways

Now in conjunction with embodiment, accompanying drawing, the present invention will be further described:

Referring to the accompanying drawing 2, firstly, four high-voltage ceramic capacitors are connected in series according to the withstand voltage design requirements, and then the capacitor bank 1 is fastened between the double-conductor plates 2 to form a ring-shaped loading line 4 . The number of capacitor banks is determined by design parameters, and the interval between capacitor banks can be adjusted. The plate material of the annular loading line is copper, and the copper tube is bent to have the same profile as the plate. In order to make the structure compact, the copper tube is welded inside the edge of the plate, which plays the role of transition and shielding the strong electric field. The capacitors and the capacitors and plates are connected by bolts and screws.

Again as accompanying drawing 3 a plurality of annular loading lines 4 are connected in series with the plexiglass support cylinder 9 as the axis, the main function of the plexiglass support cylinder is to provide mechanical support for the series loading lines, and its diameter is slightly smaller than the inner diameter of the annular loading line. Two adjacent loading lines are only connected by screws 10 at one end of the loading line, and the rest are electrically insulated from each other using electrical cardboard 3 to ensure that all connection points are on the same dotted line as shown in Figure 3 , and make the direction of two adjacent loading lines opposite from the connected end of the loading line to the other unconnected end, that is, the discharge of each level of the series loading line is carried out in the order of clockwise-counterclockwise-clockwise..., such as As shown by the arrow in Figure 3.

With reference to accompanying drawing 1, electrical paperboard is made into cone 5, and the small end diameter of cone tube is identical with annular loading line 4 external diameters, and large end diameter is identical with outer tube 7 internal diameters. Copper mesh 6 is wound on the cone, and the cone-shaped paper cylinder 5 acts as a support. The copper mesh 6 wound on it is used for grounding and discharges the current. It is necessary to ensure that the wound copper mesh is even and flat, without burrs and peak. The small-diameter end of the conical grounding cylinder 5 is connected to the lowest-level conductor copper plate of the annular series loading line 4 to ensure good contact; the large-diameter end and the outer cylinder 7 are fastened with screws.

Before adding the conical grounding cylinder, the discharge channel returns along the annular loading line 4 through the supporting grounding 8 and the connected outer cylinder 7, as shown in the path II in the figure. The area surrounded by the discharge channel is a rectangle; the conical grounding is added After the cylinder, the discharge channel returns directly from the conical grounded cylinder 5 to the connected outer cylinder 7 along the annular loading line 4, as shown in path I in the figure, and the area surrounded by the discharge channel is a triangle. It can be seen that the area enclosed by path I is about half of that of path II.

The series load line proposed by the present invention is continuously connected to the end of the forming line. When the Tesla transformer charges the forming line, it is regarded as a large capacitor, and the voltage gradually decreases along the axial direction; when the main switch is turned on and discharged, it is regarded as a transmission line. Propagates along the angular direction. On the one hand, due to this reverse connection method, the pulse propagation direction is opposite when the adjacent loading line is discharged, and the induced current caused by mutual inductance is opposite to the direction of the plate conduction current, which can just offset to a certain extent the ring-shaped loading line due to the impedance along the angular direction. The trend of increasing the output current due to the reduction of the output current makes the total output current tend to be stable, so the output voltage waveform is better than that of the discharge waveform when connected in the same direction; The discharge channel reduces the area surrounded by the internal and external discharge channels during discharge, which can significantly reduce the additional inductance of the series structure of the loading line, thereby improving the high-frequency performance of the series loading line and making its output voltage waveform better.

Claims (2)

1. A connection structure of an annular series loading line, comprising an annular series loading line (4), a plexiglass support cylinder (9), a grounding support (8), and an outer cylinder (7); it is characterized in that it also includes a tapered paper cylinder (5) and copper mesh (6); a tapered paper tube (5) is provided between the annular series loading line (4) and the outer cylinder (7), and the copper mesh (6) is wound on the tapered paper tube (5) , the small diameter end of the tapered paper tube is connected to the lowest stage of the annular series loading line (4), and the large diameter end is connected to the outer cylinder (7); the connection structure does not include the shielding at the front end of the annular series loading line (4) ring. 2. The connection structure of the annular series loading line according to claim 1, characterized in that: the diameter of the small end of the tapered paper tube (5) is the same as the outer diameter of the annular series loading line (4), and the diameter of the large end is the same as the outer diameter of the annular series loading line (4). Outer cylinder (7) internal diameter is identical.