JPH0734659B2 - High voltage pulse power supply - Google Patents

Description

The present invention relates to a high voltage pulse power supply, and more particularly to a high voltage pulse power supply which receives a high voltage pulse power supply and generates a plurality of high voltage pulses.

[Conventional technology]

In an electron tube that requires a high voltage such as a gyrotron, it may be necessary to supply a pulse voltage to the cathode and a pulse voltage to the anode at the same time. Conventionally, the structure shown in FIG. 3 has been used for this purpose. That is, a high pulse voltage is supplied from the terminal 20, the resistor 4 and the control electron tube 5 as a switching element are connected in series, and the control electron tube 5 is controlled to obtain a pulse voltage of a desired waveform at the anode output terminal 9. . The pulse power supply configured as described above is entirely housed in an oil tank because of high voltage insulation.

However, a large value of stray capacitance is present between each electrode and accessories of the control electron tube 5 and the oil tank at ground potential.
Since Cs exists, the voltage drop across the resistor 4 due to the current charging this stray capacitance Cs is large. Figure 4 (1),
Referring to the waveforms shown in (2) and (3), time t =
The input waveform Vi of the electron tube 5 is (3) from t ₀ to t = t _1.
, As shown in, the Va must also be zero at this time. However, at the time t = t ₀ , the current of the value of the rising speed of the voltage of Vk, the product of dv / dt and the stray capacitance Cs, flows through the resistor 4 to cause a voltage drop. This value reaches 13 kV for a required Va voltage of 30 kV as shown in FIG.

[Problems to be Solved by the Invention]

An object of the present invention is to solve the obstacle due to the stray capacitance in this kind of high voltage pulse power supply, and an object thereof is to obtain a desired pulse voltage of a plurality of waveforms.

[Means for Solving the Problems]

In the present invention, in order to solve the above-mentioned problems, a first pulse voltage supplied from a high-voltage pulse power supply is composed of a resistor and a switching means connected in series with each other, and a divided voltage output is obtained from the series connection point. In the configuration for generating the second high-voltage pulse output narrower than the pulse width of the first high-voltage pulse by the generated voltage-division switching means, the voltage-division switching means is shielded and the shield body is shielded by the first high-voltage pulse. It constitutes means for connecting to the high potential point of the pulse power supply.

[Action]

Therefore, the shield body can equivalently remove the harmful voltage drop due to the stray capacitance, so that the pulse output voltage having a plurality of predetermined waveforms can be obtained.

〔Example〕

FIG. 1 is a diagram showing an embodiment of the present invention. First, the structure will be described. The high voltage charged in the capacitor bank 1 is connected to the cathode of the control electron tube 2. The grid electrode of the control electron tube 2 is driven by the control circuit 21. Further, the anode of the control electron tube 2 is connected to the cathode output terminal 8 via the oil tank 3 and is also connected to the voltage division detection circuit by the resistors 23 and 24, and this detection signal is sent to the control circuit 21. Connected to the inverting input terminal. The non-inverting input terminal of the control circuit 21 is connected to the terminal 22 via an optical fiber for insulation.

A resistor 4 and a control electron tube 5 are connected in series between the cathode potential and the ground potential in the oil tank 3. A resistor 42 and a resistor 43, which are connected in series, are connected in parallel with the resistor 4 to form an anode voltage detection circuit. Further, capacitors 44 and 45 are connected in parallel to the resistor 42 and the resistor 43, respectively, and serve to correct the phase. This detection signal is connected to the control circuit 51. A signal connected via the optical insulating means 52 is input to the other input terminal of the control circuit 51 . Since the auxiliary power supply 53 for operating these circuits and the filament power of the control electron tube 5 floats at a high potential, it is insulated and supplied by the insulating transformer 54. The control electron tube 5, the control circuit 51 and the auxiliary power supply 53 are covered with the first shield body 6 and connected to the cathode of the control electron tube 5.
A second shield body 7 is provided at a substantially constant distance from the outer circumference of the first shield body 6 and is connected to the cathode potential point B.

In the high voltage pulse power supply configured in this way, the terminals
When a wide pulse is input from 22, a high voltage pulse corresponding to this waveform is generated at the cathode output terminal 8 as shown in FIG. Next, when a signal having a waveform as shown in FIG. 2 (3) is input from the terminal 57, a current corresponding to this waveform flows through the control electron tube 5. In this case, the anode output should be zero from time t ₀ to t ₁ , but a current flows through the stray capacitance according to the rising speed of the voltage at time t ₀ , that is, dv / dt. By the way, since the second shield body 7 is connected as described above, there is almost no stray capacitance, so that no unnecessary voltage is generated as shown in FIG. 2 (2). The subsequent waveforms from time t1 to tn operate without any problem, and the relationship between the input signal (3) and the anode output waveform (2) is almost proportional.

In the present embodiment, the action of the first shield body 6 is to electrically and mechanically integrate the control electron tube 5 charged to a high voltage and the auxiliary circuit, and to wrap them up so that the electric field on the outer surface is equal. This is to ensure the insulation design by keeping the potential surface and making the electric field to the periphery uniform. Therefore, it is preferable that the metal or the conductive material is continuously formed in a substantially planar shape. It may be a mesh. Further, even if it is not necessarily a conductive material, a solid insulator having a permittivity sufficiently higher than that of the surrounding insulating medium fulfills its purpose.

Although the second shield body 7 is directly connected to the cathode potential point B in this embodiment, the control characteristics are delicately changed by connecting the second shield body 7 through the impedance element having a low value in series. It can also be adjusted.

Further, in this embodiment, the shield body 41 of the resistor 4 is connected to the cathode potential point B, but by connecting the shield body 41 to the junction point A of the resistor 42 and the resistor 43, The functions of the capacitors 44 and 45 can also be combined. If the equivalent value is appropriate, either one or both of the capacitors 44 and 45 can be omitted.

The control electron tubes 2 and 5 can also be composed of semiconductors connected in series. Further, if the output voltage polarities need to be reversed, those having polarities can be configured by selecting those having polarities with respect to each component.

〔The invention's effect〕

Since the present invention has the characteristics as described above, it is possible to obtain a predetermined waveform and voltage in this type of high voltage pulse power supply.

[Brief description of drawings]

FIG. 1 shows an embodiment of a high voltage pulse power supply according to the present invention, and FIG. 2 shows waveforms for explaining the operation. FIG. 3 shows an example of a conventional high voltage pulse power supply, and FIG. 4 shows waveforms for explaining the operation. 1 …… Capacitor bank, 2 …… Control electron tube 21 …… Control circuit, 22 …… Terminal, 23, 24 …… Resistor 3 …… Oil tank, 4 …… Resistor, 41 …… Shield cylinder 42, 43… … Resistor, 44,45 …… Capacitor 5 …… Control electron tube, 51 …… Control circuit, 52 …… Optical insulation means, 53 …… Auxiliary power supply 54 …… Insulation transformer, 55,56,57 …… Terminal 6 …… First shield body, 7 …… Second shield body 8 …… Cathode output terminal, 9 …… Anode output terminal 10 …… Grounding terminal, 20 …… terminal, 50 …… Stray capacitance

Claims (1)

[Claims] 1. A high voltage pulse power source for generating a first high voltage pulse, a resistor and a switching means connected in series between a high potential point and a low potential point of the high voltage pulse power source, Voltage division switching means for generating a divided voltage output from the series connection point thereof, and voltage division switching means for generating a second high voltage pulse narrower than the pulse width of the first high voltage pulse; and the high voltage pulse power supply. High-voltage pulse power supply comprising a shield body connected to the high-potential point to shield the voltage division switching means.