JP2667024B2 - Pulse power supply - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention is used as a power source for a particle accelerator, a high-frequency pulse generator, or the like, has a fast rise time, and has a small fluctuation of a wave front value. The present invention relates to a pulse power supply device capable of generating a rectangular pulse.

(Prior Art) Conventionally, as a method of generating a rectangular wave pulse, a pulse shaping circuit (PFN) in which a coil and a capacitor are connected in a ladder shape as shown in FIG. 5 has been mainly used. Also,
In recent years, a particle acceleration power source used for a free electron laser or a particle accelerator using a high frequency has been required to have a peak value fluctuation of about 1% in order to obtain a high-quality particle beam. Quality improvement has been required. However, in the pulse shaping circuit as shown in FIG. 5, the peak value is changed by the time variation of the value of the load 6, the high-voltage pulse transformer 4, other characteristics, and the stray capacitance and stray inductance of the high-voltage portion. It is not always easy to reduce the fluctuation. Therefore, in such a pulse shaping circuit, as shown in FIG. 5, the value of the inductance of the coil is finely adjusted by making the coil 1 variable, and the fluctuation of the peak value is reduced, so that high quality is achieved. Attempts have been made to obtain a square wave.

(Problems to be Solved by the Invention) However, recently, the accelerating voltage of the particle beam has been increasingly increased, and accordingly, the pulse power supply has also been increased in voltage. became. Therefore, in such a situation, it is necessary to prevent dielectric breakdown of the accelerating portion, and the pulse width is extremely short.
Moreover, a pulse having a steep rise is required. However, in the conventional pulse shaping circuit as shown in FIG. 5, since the lumped elements are used, both the rising steepness and the pulse width are restricted, and the desired one cannot be obtained.

As the switch 5, a magnetic switch using a saturable reactor can be applied in addition to a switch element such as a thyratron. Such a magnetic switch is
The switch does not have a finite life like a thyratron or the like, and is a switch very suitable for a power supply for generating a high repetition pulse (a power supply that generates tens to thousands of pulses per second). However, in the conventional magnetic switch, the timing of turning on the switch cannot be controlled, and only the transition from the OFF state to the ON state is automatically performed when transitioning from the unsaturated state to the saturated state. However, in order to generate a high-quality rectangular wave pulse, it is necessary to turn on the switch at the wave front of the voltage waveform for charging the distributed constant line. At this time, if the frequency of charging the distributed constant line is constant, the voltage at which the magnetic switch is turned on at the wave front is determined, and if an attempt is made to generate a high-quality rectangular wave, the output voltage is always There was a disadvantage that it became constant.

Furthermore, in the related art, there is no countermeasure for “temporal fluctuation of load”, and when a load with temporal fluctuation is connected,
The desired performance could not be exhibited. That is, as an example, when the load is a vacuum tube such as a thyratron,
When an anode voltage is pulsed to a vacuum tube heated by a heater or the like to emit electrons from the cathode,
As the time elapses, the temperature of the vacuum tube increases. This is heating due to the loss of the anode voltage, which can occur very generally. Due to this temperature change, the value of the load resistance of the vacuum tube as the load changes. In general, it is known that the value of the load resistance gradually decreases.
However, when such a load resistance fluctuates with time, the conventional technology cannot cope with this, and there is a drawback that the fluctuation occurs when applied to the load.

The present invention has been made in order to solve the above-described problems, and an object of the present invention is to generate a rectangular wave pulse having an extremely steep rising edge, a short pulse width, and a small fluctuation of a peak value. It is an object of the present invention to provide a pulse power supply device that can perform the above-described operations. Another object of the present invention is to keep the voltage applied to the load constant even when the value of the load resistance changes as described above.

[Structure of the Invention] (Means for Solving the Problems) The pulse power supply device according to claim 1 of the present invention forms a distributed constant line by disposing a conductor in a grounded metal container. In a pulse power supply device in which a switch element is connected to one end, a conductor is formed by coaxially arranging two conductors consisting of a center conductor with a middle conductor formed in a spiral shape, and a conductor per unit length in each conductor. Of the spiral conductor are equal in length, a plurality of electrodes of ground potential are arranged inside the ground metal container, and the inner surface of each electrode of ground potential is substantially cylindrical and Are coaxially provided, and the electrode of ground potential is configured to be movable in the direction orthogonal to the axial direction of the ground metal container while holding the electrode coaxial with the conductor, and the plurality of ground electrodes adjacent to each other are grounded. Place a grounded metal container between the electrodes. Wherein the constant has been partition member is attached.

(Operation) In the pulse power supply device of the present invention having the above-described configuration, the ground electrode movably disposed in the ground metal container is moved in response to the time variation of the load, and the By partially adjusting the characteristic impedance, the output waveform can be adjusted, and a desired rectangular pulse can be obtained. In addition, since the specific impedance of the distributed constant line can be increased by forming the conductor in a spiral shape, it can be applied to a load having a relatively high resistance. Furthermore, by arranging the partition member between the ground electrodes, the electrical connection between the ground electrodes can be kept constant regardless of the position of the ground electrode, so that the characteristic impedance is continuously changed. And the waveform can be finely adjusted.

(Example) Hereinafter, an example of the present invention will be specifically described with reference to FIGS. 1 to 4. The same members as those of the conventional type shown in FIG. 5 are denoted by the same reference numerals, and description thereof will be omitted.

(1) Configuration of the embodiment As shown in FIG. 1, the configuration of the embodiment is such that the center conductor 22 and the intermediate conductor 23 are coaxially arranged in the grounded metal container 10 to form the distributed constant line 24. The distributed constant line 24 is operated as a bloom line. Where the center conductor
The intermediate conductor 22 and the intermediate conductor 23 are formed in a spiral cylindrical shape as shown in FIG. In this case, the center conductor 22 and the intermediate conductor
In order to make the surge propagation speed of 23 equal, the length of the spiral conductor per unit length must be equal, and the center conductor
The spiral structure of 22 is formed more densely than the spiral structure of the intermediate conductor 23.

A pulse transformer 3 and a switch 5 for supplying a high-voltage pulse are connected to one end of the line, and a load 6 is connected to the other end. In addition, the grounded metal container
A plurality of grounding electrodes 13 are provided inside 10, and a support rod 14 that penetrates the container 10 is attached to each of the grounding electrodes 13. By operating the support rod 14 by a driving device (not shown) provided outside the container 10, the ground electrode 13 is moved in a direction orthogonal to the axial direction of the container 10 while maintaining the ground potential. It is configured to be movable. That is, as shown in FIG.
Is substantially cylindrical and provided coaxially with the two conductors 22 and 23. Further, the electrode 13 at the ground potential is
It is configured to be movable in a direction orthogonal to the axial direction of the grounded metal container 10 while holding coaxially with the conductors 22 and 23, the present invention is not limited to the above-described embodiment, The type of the driving device connected to each support rod is not particularly limited, and the driving device may be configured to be capable of remote operation and automatic operation.

In addition, a ground metal container 10 is provided between adjacent ground electrodes 13 and 13.
A partition plate 15, which is a partition member fixed to the partition, is mounted. Note that the partition plate 15 may be made of metal or an insulator.

(2) Operation of Embodiment The pulse power supply device configured as described above operates as described below. That is, the characteristic impedance of the distributed constant line 12 is different from that of each ground electrode 13
Since it is determined by the relative position of 22, 23, the distributed constant line 12
By moving each ground electrode 13 according to the time variation of the load 6 connected to the container, the characteristic impedance at each part inside the container can be adjusted. As a result, a rectangular wave pulse with a small fluctuation of the peak value is obtained. In addition, the operation of moving each ground electrode 13 in a direction orthogonal to the axial direction of the container 10 is performed by driving a support rod 14 attached to each ground electrode 13 by a driving device (not shown) provided outside the container 10. Since the adjustment can be performed by driving, the adjustment work is easy. In addition, from experiments by the present inventors,
It has been clarified that by appropriately adjusting the position of each ground electrode 13 by the above-described method, a rectangular wave pulse with a small fluctuation of the peak value can be obtained.

Further, in the present embodiment, by providing the partition plate 15 between the ground electrodes 13, it is possible to always keep the electrical connection state between the ground electrodes 13 constant regardless of the position of the ground electrode 13. As a result, the characteristic impedance can be changed continuously, and the waveform can be finely adjusted. As a result, if the electrical connection between the ground electrodes 13 is different, the current distribution is different, which has conventionally been a problem, and the characteristic impedance is slightly different. As a result, the characteristic impedance can be continuously changed. The disadvantage that it becomes impossible can be eliminated. When the partition plate 15 is made of metal, the electrical connection between the ground electrodes 13 is always maintained. Also, the partition plate 15
In the case where is made of an insulating material, the ground electrodes 13 are not electrically connected to each other, but are electrically connected to the ground metal container 10, so that the ground electrodes 13 are electrically connected indirectly. It will be.

As described above, according to the present embodiment, the ground electrode movably arranged in the ground metal container is moved in response to the time variation of the load, and the specific impedance of the distributed constant line is partially adjusted. By doing so, the input waveform can be adjusted and a desired rectangular pulse can be obtained. Also, by driving a support rod disposed through the grounded metal container,
Since the waveform can be adjusted from outside the container, it is possible to easily obtain a high-quality rectangular wave pulse with little fluctuation in the peak value. Further, since the partition plate is provided between the ground electrodes, the electrical connection state between the ground electrodes can be kept constant at all times, so that the characteristic impedance can be continuously changed.

Further, in the present embodiment, since the conductor is formed in a spiral shape, the characteristic impedance of the distributed constant line 24 can be increased, so that the present invention can be applied to a load having a relatively high resistance. In particular, in the present embodiment, the center conductor 22
In order to equalize the surge propagation speed of the intermediate conductor 23, it is necessary to make the length of the spiral conductor per unit length equal, and the spiral structure of the central conductor 22 is formed more densely than the spiral structure of the central conductor 23. I have. This is for the reason described below.
That is, in general, a distributed constant line in which two substantially cylindrical structures having different radii formed by using spiral conductors are coaxially arranged in a grounded metal container having a substantially cylindrical inner surface. It is known that when operating as a bloom line, the output waveform is disturbed unless the propagation speed of the electric signal in the axial direction is made equal. However, according to experiments by the present inventors,
By making the total length of the two spiral conductors equal,
It has been found that the axial propagation speed of the electric signal can be equalized. That is, assuming that the radius of the center conductor 22 is r1, the number of turns per unit length is N1, the radius of the intermediate conductor 23 is r2, and the number of turns per unit length is N2, r1 · N1 = r2 · N2.

(3) Modification According to the experiments by the present inventors, in the present invention having the above-described configuration, the characteristic impedance of the distributed constant line formed by the combination of the spiral central conductor 22 and the intermediate conductor 23,
By equalizing the characteristic impedance of the distributed constant line formed by the combination of the spiral intermediate conductor 23 and the grounded metal container 10, it is less affected by the disturbance of the electromagnetic field at the end of the distributed constant line, It has been clarified that a bloom line capable of generating a high-quality rectangular wave can be formed. In this case, as shown in FIG.
The outer diameter of the spiral center conductor 22 arranged on the innermost side is D1, the inner diameter of the intermediate conductor 23 is D2, the outer diameter is D3, and the inner diameter of the grounded metal container is
Assuming that D4, D2 / D1 = D4 / D3 should be satisfied.

[Effects of the Invention] As described above, according to the present invention, a plurality of electrodes having a ground potential are provided inside a grounded metal container, and each ground electrode is movable in a direction orthogonal to the axial direction of the container. In addition, by providing a partition member between the ground electrodes, a pulse power supply having an extremely steep rising edge, a short pulse width, a small peak value fluctuation, and capable of generating a square wave pulse is provided. An apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic circuit diagram showing one embodiment of the pulse power supply device of the present invention, FIG. 2 is a diagram for explaining the structure of the spiral conductor used in the embodiment of FIG. 1, and FIG. FIG. 4 is a schematic circuit diagram showing a modification of the present invention, and FIG. 5 is a schematic circuit diagram showing an example of a conventional pulse shaping circuit. DESCRIPTION OF SYMBOLS 1 ... Variable coil, 2 ... Capacitor, 3,4 ... Pulse transformer, 5 ... Switch, 6 ... Load, 7 ... Pulse shaping circuit, 10 ... Ground metal container, 13 ... Ground electrode, 14 …
... Support rods, 15 ... Partition plate, 22 ... Center conductor, 23 ... Intermediate conductor, 24 ... Distributed constant line, 30 ... Guide.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Kenichi Nojima 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Toshiba Hamakawasaki Plant (72) Inventor Satoru Yanagibu 2-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa No. Inside the Toshiba Hamakawasaki Plant

Claims (1)

(57) [Claims] 1. A pulsed power supply device in which a conductor is arranged in a grounded metal container to form a distributed constant line, and a switch element is connected to one end of the distributed constant line, wherein the conductor is formed in a spiral shape. In addition, two conductors consisting of an intermediate conductor and a central conductor are coaxially arranged, and the length of the spiral conductor per unit length in each conductor is equalized. A plurality of ground potential electrodes are provided, the inner surface of each ground potential electrode is substantially cylindrical and provided coaxially with the two conductors, and the ground potential electrode is coaxial with the conductor. Is configured to be movable in a direction orthogonal to the axial direction of the grounded metal container, and a partition member fixed to the grounded metal container is attached between adjacent ground electrodes of the plurality of ground electrodes. Is characterized by being Pulse power supply.