JPH089643A - Schenkel type high voltage dc power source - Google Patents

Abstract

PURPOSE:To reduce high-frequency ripples without using an inductance regulating coil by providing a ferrite core displaceable in the axial direction of a step-up coil in the step-up coil. CONSTITUTION:A stepping motor 36 is forward or reversely driven to rotate an insulation drive shaft 32 via a bevel gear 35. As the shaft 32 is rotated, a ferrite core 38 disposed between a secondary U-phase coil 42 and a secondary V-phase coil 42' is displaced in the axial direction of a step-up coil by a threaded part 321 of the shaft 32 and a screw mechanism of a jack 40 engaged with the part 321, thereby relatively regulating the induction coupling degree of the primary coil with the secondary U-phase coil and the secondary V-phase coil, and the position of the core 38 is so regulated that the high-frequency induced ripple to be superposed on the DC output voltage is minimized. Thus, a coil for regulating the inductance is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Schenkel type DC high voltage power supply device in which a ripple voltage superimposed on a DC output voltage is reduced.

[0002]

2. Description of the Related Art FIG. 2 is a basic circuit diagram of a balanced type Schenkel type DC high voltage power source used as an accelerating voltage source for charged particles in an ion implantation apparatus, an electron beam irradiation apparatus and the like. The high-voltage power supply as a whole is composed of a high-frequency oscillation power supply unit 1 of several tens of kHz and a rectifying and multiplying unit 2 fed from the power supply unit. The plate of the oscillation tube 3 in the high-frequency oscillation power supply unit 1 is connected to the positive terminal of the DC power supply 5 via the primary coil 4 ₁ of the boosting coil 4, and the cathode of the oscillation tube is grounded. One ends of the secondary U-phase coil 4 ₂ and the V-phase coil 4 ₂ ′ of the booster coil 4 have U-phase radio frequency (RF) electrodes 6 and V each having a shape obtained by dividing the cylinder in the rectifying and multiplying unit 2 into two.
It is connected to a phase radio frequency (RF) electrode 6 ', and the other ends of these coils are grounded via ripple adjusting coils 7 and 7'.

FIG. 3 is a block diagram of the booster coil 4. The booster coil is housed in a pressure container 8 filled with a high-pressure insulating gas, and the container is a pressure container 9 that houses the rectifying and multiplying unit 2. It is in communication. The step-up coil is configured by symmetrically arranging the primary and secondary coil parts on both sides of the central insulating plate 21, and the coil parts 4 ₁₁ of the primary coil are provided on both surfaces of the two insulating plates 22 to form a plurality of coil parts. The coil portions 4 ₂ u and 4 ₂ v of the secondary coil are provided on both surfaces of the insulating plate 23. Each insulating plate 21, 22, 23 is fastened by a plurality of insulator bolts 24, and all coil portions 4 ₁₁ of the primary coil are connected in series to form a primary coil 4 _1. The respective coil portions 4 ₂ u are connected in series to form a secondary U-phase coil 4 ₂ , and the respective coil portions 4 ₂ v are connected in series to form a secondary V-phase coil 4 ₂ ′. Then, by mounting the central insulating plate 21 on the support member 25 fixed to the pressure vessel 8, the boosting coil 4 is installed in the vessel.

A large number of narrow shield electrodes 10, 10 'are provided inside the high-frequency electrodes 6, 6', respectively, and the stray capacitance between the high-frequency electrodes and the shield electrodes acts as a rectifying and multiplying capacitor. Between the ground point and the shield electrodes 10 and 10 'of the lowest pressure stage, the shield electrode 10 of each stage
And 10 'and the shield electrodes 10' and 10 of the higher voltage stage, and between the shield electrodes 10 and 10 of the highest pressure stage and the high voltage terminal electrode 11, a rectifier 12 of the illustrated polarity is connected. (There is also a type in which the shield electrode of the lowest pressure stage is connected to the ground point without a rectifier, and the shield electrode of the highest pressure stage is connected to the high voltage terminal electrode without a rectifier).

In the grid biased to the negative potential of the oscillation tube 3 of the high frequency oscillation power supply unit 1, for example, 2 of the boosting coil 4 is provided.
An excitation voltage is applied from the pickup coil 13 that is inductively coupled to the secondary coil, whereby the high frequency oscillation power supply unit 1 oscillates, and the oscillation frequency is the inductance of the secondary coil of the boosting coil 4 and this secondary coil. It is the resonance frequency of the resonance circuit formed by the floating electrostatic capacitance in parallel relationship with. The stray capacitance between the high frequency electrodes 6 and 6 ′ connected to the secondary U-phase coil 4 ₂ and the V-phase coil 4 ₂ ′ of the booster coil 4 and the shield electrodes 10 and 10 ′ of each stage is 2 A direct current voltage obtained by sequentially rectifying and multiplying the next coil voltage is generated, and a high positive polarity direct current output voltage is obtained at the high voltage terminal electrode 11.

[0006]

In the balanced type (full-wave rectification type) Schenkel type DC high-voltage power supply, the symmetry of the circuit components in principle has the advantage that the high frequency induction component in the DC output voltage becomes zero. However, in reality, it is impossible to manufacture them in perfect symmetry due to the limitations of working and installation of high-frequency electrodes, shield electrodes, etc., and an imbalance of stray capacitance occurs. Along with this, the high frequency induction component does not become zero, and the ripple voltage superimposed on the DC output voltage increases. Therefore, the ripple adjusting coils 7 and 7'installed outside the pressure tank are connected to the ground side of the secondary coils 4 ₂ and 4 ₂ 'of the boosting coil 4, and the inductance of the resonance circuit is adjusted by the adjusting coil. By adjusting the balance state of the voltage applied to the rectifying and multiplying unit 2, the ripple voltage due to the high frequency induction component is reduced.

However, the inductance adjusting coils 7 and 7'are generally large in size. For example, in the case of being used for a mega high voltage (MV) class DC high voltage power supply, if an inductance adjusting coil is used to obtain a variable amount of 5% with respect to the inductance of each phase of U and V, a coil of about 30 turns is wound. In addition, it requires a mechanism to finely adjust the inductance by short-circuiting the coil sides continuously, and when a current in a resonant state is passed through such an adjustment coil, it is necessary to perform atmospheric insulation and cooling. In addition, an inductance adjusting coil device larger than the pressure vessel 8 is required, and the size of about 2 m square is included when the accommodating vessel is included, resulting in a very bad space factor in view of the entire DC high voltage power supply. Furthermore, the adjustment coil 7,
'For connection with the secondary coil 4 _2, 4 _2' 7 ground connection line of the must drawn out of the pressure vessel 8.

It is an object of the present invention to provide a Schenkel type DC high voltage power supply which does not use an inductance adjusting coil and which reduces high frequency induction ripple superimposed on a DC output voltage.

[0009]

SUMMARY OF THE INVENTION The present invention provides a primary coil which is supplied with power from a high frequency power source and two two coils which are arranged on both sides of the primary coil and which respectively supply power to two high frequency electrodes.
In a Schenkel type DC high voltage power supply device having a boost coil consisting of the following coil, in the boost coil,
The main feature is that a ferrite core that is displaceable in the coil axis direction is provided.

Further, the present invention comprises a primary coil fed from a high frequency power source, and two secondary coils arranged on both sides of the primary coil and respectively feeding two high frequency electrodes, and housed in a pressure vessel. In a Schenkel-type DC high-voltage power supply device including a booster coil, an insulating drive shaft that penetrates the inside of the booster coil and extends to the outside of the pressure vessel, and a screw mechanism for the insulating drive shaft that penetrates inside. And a ferrite magnetic core that is displaceable in the axial direction of the booster coil.

[0011]

[Function] By displacing the ferrite core provided inside the booster coil in the coil axis direction, the degree of inductive coupling between the primary coil and each secondary coil changes, and the voltage applied to each high-frequency electrode is balanced. The state can be adjusted. The position of the ferrite core is adjusted so that the ripple superimposed on the DC output voltage is minimized.

By rotating the insulating drive shaft from the outside of the pressure vessel, the position of the ferrite magnetic core coupled to the drive shaft via the screw mechanism can be finely adjusted.

[0013]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram of a boosting coil unit in a Schenkel type DC high voltage power supply device, and the same reference numerals as those in FIG. 2 denote the same parts. The booster coil 4 housed in the pressure vessel 8 includes a primary coil 4 ₁ connected to a high frequency power source and a secondary coil 4 ₂ , 4 ₂ ′ for feeding two high frequency electrodes on both sides of the central insulating plate 21. The parts 4 ₁₁ , 4 ₂ u and 4 ₂ v are arranged symmetrically, one end of each secondary coil is connected to the high frequency electrodes 6, 6 ′, and the other end is connected to the ground point. A central insulating plate 21 supporting the entire booster coil, an insulating plate 22 provided with coil parts 4 ₁₁ of the primary coil 4 ₁ on both sides, and coil parts 4 ₂ u of the secondary coils 4 ₂ , 4 ₂ ′, 4 ₂
The insulating plate 2 provided with v on both sides has a central opening 30.
Are formed, and each insulating plate has an annular shape.

A mechanism 31 for varying the degree of inductive coupling between the primary coil and the secondary coil, which uses a ferrite magnetic core, is provided inside the booster coil 4 so as to penetrate through the central openings of the insulating plates 21, 22, and 23. An insulating drive shaft 32 made of an insulating material penetrating the inside of the booster coil 4 extends out of the pressure vessel through a guide flange 33 with a seal attached to each of the upper and lower flanges 8 ₁ and 8 ₂ of the pressure vessel 8. The thrust bearing 34 pivotally supports the upper end of the drive shaft. Insulating drive shaft 32 of the lower end reversing allowed through the bevel gears 35 stepping - is connected to the motor 36, the motor - motor is attached to a support member 37 fixed to the lower flange ₈₂ of the pressure vessel.

A ferrite magnetic core 38 whose position is displaced by the rotation of the insulating drive shaft 32 is provided inside the boosting coil 4. The ferrite core has a cylindrical shape, and the insulating drive shaft 32 passes through the inside thereof. Ferrite core 3
A guide ring 3 into which the insulated drive shaft 32 is fitted at the upper end of
9 is attached to the lower end of the magnetic core by using a bolt 41, and a jack nut 40 screwed with the male screw portion 32 ₁ formed on the insulated drive shaft is attached. Further, the ferrite core 38 has longitudinal grooves 38 ₁ for detent is formed in the groove, for example, it engaged detent pawl 42 mounted is fitted in the center insulating plate 21. Ferrite core 3
8 is connected to the ground potential, the magnetic core, a secondary coil 4 _2,
To generate a voltage of 4 ₂ 'to a position where the space insulation can be sufficiently secured, is provided enters into the secondary coil.

Secondary U-phase and V-phase coil 4 of boost coil 4
One end of ₂ and 4 ₂ 'is two high frequency electrodes in the rectification and multiplication section of the Schenkel type DC high voltage power supply (reference numerals 6 and 6'in Fig. 2).
The other ends of these coils are connected to the ground point. By oscillating the high frequency oscillating power source and supplying power to the rectifying and multiplying unit, a high DC output voltage is generated at the high voltage terminal electrode (11 in FIG. 3).

The stepping motor 36 is normally or reversely driven to rotate the insulating drive shaft 32 via the bevel gear 35. The ferrite magnetic core 38 arranged between the secondary U-phase coil 4 ₂ and the secondary V-phase coil 4 ₂ ′ along with the rotation of the insulating drive shaft is the screw portion 32 ₁ of the drive shaft and the jack nut screwed to this. By the screw mechanism of 40, the booster coil is displaced in the axial direction, and the degree of inductive coupling between the primary coil, the secondary U-phase coil, and the secondary V-phase coil is relatively adjusted. The position of the ferrite core 38 is finely adjusted so that the balance state of the voltage applied to the two high frequency electrodes is relatively adjusted and the high frequency induction ripple superimposed on the DC output voltage is minimized.

[0018]

Since the present invention is configured as described above, the degree of inductive coupling between the primary coil and each secondary coil is changed by adjusting the position of the ferrite magnetic core provided inside the boosting coil. Since the balance state of the voltage applied to the high frequency electrode can be adjusted, the high frequency induction ripple superimposed on the DC output voltage can be reduced. Unlike the conventional case, it is not necessary to provide a large inductance adjusting coil, and it is not necessary to draw the connecting wire of the secondary coil out of the pressure tank.

Since the ferrite core is provided inside the booster coil, the inductive coupling between the primary coil and the secondary coil is better than that of the conventional air core type, and the booster fed from the high frequency power source is boosted. The required power of the coil can be reduced.

Since the mechanism for varying the degree of inductive coupling between the primary coil and the secondary coil is provided inside the booster coil, the high-pressure insulating gas filled in the pressure vessel is convected through the booster coil. Therefore, the booster coil can be cooled well.

Since the ferrite magnetic core is connected to the insulating drive shaft via a screw mechanism, the position of the ferrite magnetic core can be finely adjusted by rotating the insulating drive shaft from outside the pressure vessel.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part and a boost coil part of an embodiment of the present invention.

FIG. 2 is a basic circuit diagram of a balanced type Schenkel type DC high voltage power supply.

FIG. 3 is a configuration diagram of a conventional boost coil unit.

[Explanation of symbols]

4 booster coil 4 ₁ primary coil 4 ₂ secondary U-phase coil 4 ₂ 'secondary V-phase coil 30 opening 32 of the coil mounting insulating plate insulating drive shaft 32 ₁ threaded portion 33 seals the guide flange 34 thrust bearing 35 Umbrella Gear 36 Stepping motor 38 Ferrite core 38 ₁ Vertical groove 39 Guide ring 40 Jack nut 42 Non-rotating pawl

Claims (2)

[Claims] 1. A Schenkel type DC having a booster coil comprising a primary coil fed from a high frequency power source and two secondary coils arranged on both sides of the primary coil and respectively feeding two high frequency electrodes. In the high voltage power supply device, a Schenkel type DC high voltage power supply device characterized in that a ferrite magnetic core displaceable in the coil axis direction is provided inside the booster coil. 2. A booster housed in a pressure vessel, which comprises a primary coil fed from a high-frequency power source and two secondary coils arranged on both sides of the primary coil to respectively feed two high-frequency electrodes. In a Schenkel type DC high voltage power supply device including a coil, an insulating drive shaft that penetrates the inside of the booster coil and extends to the outside of the pressure vessel, and the insulating drive shaft that penetrates inside through a screw mechanism. Combine,
A Schenkel-type DC high-voltage power supply device comprising a ferrite core that is displaceable in the axial direction of the booster coil.