JPH09149645A - High voltage generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a high voltage generator in which the efficiency of high frequency power supply is enhanced and the ripple voltage superposed on high voltage output can be suppressed easily. SOLUTION: A current IL flowing through a reactor L2 offsets a current IC flowing between the input terminals of a rectifier circuit 1 to prevent the secondary current of transformers T1 , T2 from increasing thus preventing the efficiency of AC power supply from lowering due to increase of current on the primary of transformer. Ripple voltage superposed on high voltage output is suppressed by sliding a ground terminal A on a resistor R1 to vary the voltage being distributed to the rectifier circuit, matching the amplitude of voltage between the transformers T1 , T2 , switching the ground terminal B to one of the taps a, b,..., m, n and altering the ground position on the reactor L2 , and then varying the voltage phase of transformers T1 , T2 .

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high voltage generator using a balanced Cockcroft-Walton circuit. In a high voltage generator using a balanced Cockcroft-Walton circuit, ripple voltage is generated in a high voltage output due to electrical and mechanical imbalance of a transformer and a multistage high voltage rectifier circuit. Although superposed, FIG. 1 shows a conventional high voltage generator having a structure for reducing the ripple voltage. Figure T ₁ and T ₂ are the connected isolation transformer to a high-frequency power supply V _0, the AC voltage from the high-frequency power source V ₀ is boosted by the transformer T ₁ and T _2. This transformer T ₁ and T
_{One ends of the second secondary coil are} connected by a _{ripple correction resistor R 1,} the resistor R ₁ are slidable ground terminal A is attached on the resistor R _1. On the other hand, the other end of the secondary coil of the transformers T ₁ and T ₂ is connected to the multistage high voltage rectifier circuit 1
Of the transformers T ₁ and T ₂ are rectified by the multistage high-voltage rectifier circuit 1.
High-voltage take-out resistors R ₂ and R ₃ are connected to the output terminal of the multi-stage high-voltage rectifier circuit 1, and a high voltage is applied to the resistor R ₂
And a high voltage output terminal T provided between R ₃ and R ₃ . In such a configuration, the adjustment to reduce the ripple voltage superimposed on the high voltage output, the distribution of the voltage supplied to the rectifier circuit 1 is slid resistor R ₁ above the ground terminal A By changing the amplitude of the voltage of the transformer T ₁ and the amplitude of the voltage of the transformer T ₂ , the position of the high voltage output terminal T is mechanically moved so as to be present in parallel with each of the high voltage extracting resistors R ₂ and R _3. Distributed capacity C ₂ ,
This is done by adjusting the distribution of C ₃ . FIG. 2 shows another conventional high voltage generator having a structure for reducing the ripple voltage, and the same reference numerals as those in FIG. 1 indicate the same structure. In the high voltage generator of FIG. 2, the ripple correction variable resistor R ₁ ′ and the ripple correction variable reactor L ₁ are connected in series at one end of the outputs of the transformers T ₁ and T ₂ , and the middle point is grounded. There is. In such a configuration, the adjustment for reducing the ripple voltage superimposed on the high voltage output is performed by changing the resistance value of the ripple correction variable resistor R ₁ so that the voltage of the transformer T _{1 and} the voltage of the transformer T ₂ are changed. This is done by matching the amplitudes and changing the phase of the voltage of the transformer T ₂ by changing the reactor of the ripple correction variable reactor L ₁ . By the way, FIGS.
In the high voltage generator shown in FIG. 1, a current I is applied between the input terminals of the rectifier circuit 1 due to the capacitance component of the rectifier circuit 1.
_{C flows,} the current on the secondary side of the _{transformers T 1} and T ₂ rises, and the current on the primary side rises due to the induction, which increases the power consumption of the high-frequency power source V _{0.
The efficiency of 0 decreases. Further, in the high voltage generator shown in FIG.
Is the position of the high voltage terminal T located in the ultra high voltage.
Turn off the power to the high-pressure tank before adjusting the
It has to be opened and its adjustment work is very troublesome.
It is. On the other hand, in the high voltage generator shown in FIG.
, Depending on the degree of balance deviation, the variable resistor for ripple correction may
The} ripple voltage may not be reduced unless the _{anti-R 1} ′ and the ripple correction variable reactor L ₁ are connected and adjusted respectively. Therefore, the ripple correction variable resistor R ₁ ′ and the ripple correction variable reactor L ₁ are connected. The work of is very troublesome. The present invention has been made in view of the above circumstances, and an object thereof is to generate a high voltage which has a high efficiency of a high frequency power supply and which can easily reduce a ripple voltage superimposed on a high voltage output. To provide a device. Therefore, the high voltage generator of the present invention includes a first and a second transformer for boosting a voltage from an AC power supply, and outputs of the first and second transformers. A resistor that connects one ends to each other, a first grounding unit that sets an arbitrary position of the resistor to a ground potential, a rectifying circuit that is connected to the other ends of the outputs of the first and second transformers, and the rectifying circuit. A reactor connected in parallel to the rectifier circuit at the input end of
Second grounding means for setting an arbitrary position of the reactor to a ground potential is provided. Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 3 shows an example of the high voltage generator of the present invention. In the figure, the same reference numerals as in FIG. 1 indicate the same components. In the configuration of FIG. 3, the input terminal of the multistage high voltage rectifier circuit 1 is connected in parallel with the rectifier circuit to a reactor L.
₂ is connected, and a, b, ..., Is connected to this reactor L ₂ .
A plurality of taps of m and n are set up. B is a ground terminal maintained at the ground potential, and the ground terminal B is the tap a,
It is connected to one of b, ..., M, n, and the switching is possible. The position of the high voltage output terminal is fixed. Now, as the reactor L ₂ , a current I that cancels out the current I _C flowing between the input terminals of the rectifier circuit 1.
_{Since the} one that flows _L between its input terminals is selected, the current on the secondary side of the transformers T ₁ and T ₂ does not increase. As described above, in the configuration of FIG. 3, the reactor L ₂ connected to the input end of the multistage high-voltage rectifier circuit 1 and the capacitive component of the multistage high-voltage rectifier circuit 1 resonate to resonate the high-frequency power source V ₀ . Efficiency is improved. Further, in the configuration of FIG. 3, the adjustment for reducing the ripple voltage superimposed on the high voltage output is supplied to the rectifier circuit 1 by sliding the ground terminal A on the resistor R _1. Voltage of transformer T ₁ and transformer T ₂
, The ground terminal B is switched and connected to one of the taps a, b, ..., M, n to change the grounding position on the reactor L ₂ to change the voltage of the transformer T ₁ and the transformer T _{1. This} is done by changing the phase of the voltage of ₂ .
Even if the grounding position on the reactor L ₂ is changed, the resonance current flowing in the reactor L ₂ does not change, so that the efficiency of the power supply does not decrease. As described above, according to the present invention, the efficiency of the high frequency power source is improved, and the ripple voltage superimposed on the high voltage output is reduced only by adjusting the ground terminals A and B kept at the ground potential. Therefore, it is not necessary to perform the troublesome work of mechanically adjusting the position of the high voltage output terminal and the troublesome work of connecting the ripple correction variable resistor and the ripple correction variable reactor as in the conventional case. According to the present invention, a reactor is connected in parallel with the rectifier circuit at the input end of the rectifier circuit, and a current that cancels the current flowing between the input ends of the rectifier circuit due to the capacitance component of the rectifier circuit is applied. Since it is made to flow into the reactor, the efficiency of the AC power supply is improved. In addition, a ground position of the resistor connected to one end of the secondary coil of the first and second transformers,
The ripple voltage superimposed on the high voltage output can be easily reduced only by adjusting the input end of the rectifier circuit and the ground position of the reactor connected in parallel to the rectifier circuit.

[Brief description of the drawings]

FIG. 1 is a diagram showing a conventional high voltage generator.

FIG. 2 is a diagram showing a conventional high voltage generator.

FIG. 3 is a diagram showing an example of a high voltage generator of the present invention.

[Explanation of symbols]

1 Multi-stage high voltage rectifier circuit V ₀ High frequency power supply T ₁ , T ₂ Insulation transformer R ₁ Ripple correction resistor A, B Ground terminal L ₁ Ripple correction variable reactor R ₁ ′ Ripple correction variable resistor L ₂ Reactor R ₂ , R ₃ High voltage output resistance T High voltage output terminal

Claims (1)

[Claims] 1. A first and second transformer for boosting a voltage from an AC power supply, a resistor connecting one ends of outputs of the first and second transformers, and an arbitrary position of the resistor is grounded. A first grounding means, a rectifier circuit connected to the other ends of the outputs of the first and second transformers, and a reactor connected to the input terminal of the rectifier circuit in parallel with the rectifier circuit,
A high voltage generator comprising: second grounding means for setting an arbitrary position of the reactor to a ground potential.