JPH0332364A - Power source device - Google Patents

Abstract

PURPOSE:To prevent partial magnetism by inserting capacitors between thyristor power controllers and a transformer. CONSTITUTION:A power device is constituted of a three phase thyristor power controller 12, three phase transformer 13 and three phase full wave rectifier 14, and the output making rectification smooth 5-6 is supplied to the load 7. The above mentioned controller 12 is controlled by phase angle controllers 16R-T. Capacitors 15R-T are inserted between primary side of each phase of the transformer 13 and R-T phase power controllers 16R-T. As the result, a DC portion is cut by the capacitor 15, and it never flows into the transformer 13.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power supply device suitable for use in a short-circuited load such as an electron beam gun.

[Conventional technology]

FIG. 2 shows a conventional power supply circuit using a thyristor voltage regulator. In the figure, 1 is a single-phase AC power supply (
Voltage V. ), 2 is a thyristor power regulator, A and H are thyristors connected in antiparallel to each other, 3 is a step-up transformer, 4 is
5 is a reactor I/L, 6 is a capacitor, and 7 is a DC load. 8A and 8B are voltage dividing resistors, and 9 is a voltage command device. Voltage command v'' sent by voltage command unit 9
and the voltage vf across resistor 8B is i! 1′! ax amplifier 1
06; When two people work together, is the deviation ε between them on the phase angle side? 1fll
It is manually powered by vessel 11. The phase angle controller 11 receives the gate signal G.
. , GII to the gates of thyristors A and B, respectively.

In this configuration, the zyristors A and B alternately receive gate signals GA and Gll and become conductive, and the zyristor power regulator 2 sends out an alternating current voltage Vl as shown in FIG. 3 (+1). The controlling fall angles of A, , and B are α
, β, the output of the thyristor power regulator 2 can be adjusted by increasing or decreasing the control angles α and β. The output of the thyristor power regulator 2 is supplied to a full-wave rectifier 4 via a transformer 3, where it is converted to direct current, and then converted into a smoothing Ij consisting of a reactor 5 and a condenser 6.
It is slipped by iI7 on the jl path and is supplied to the DC load 7.

In this case, if the control angle is α - β, the average value of the voltage ■, will be O, and the voltage ■ will be completely alternating current, but due to the characteristics of thyristors A and B, the control angles α and β will be slightly However, if there is a difference, on the smaller side of the control angle, for example, when α<β, the current will be an alternating current that includes a direct current component on the positive side. As is well known, when a complete alternating current with no direct current component is applied to the transformer 3, magnetic flux in the positive direction and magnetic flux in the opposite direction are generated alternately and equally, so no residual magnetic flux occurs. As shown in Section 2, if the condition α<β continues, the residual magnetic flux of the square IRJ due to the DC component increases every cycle, the iron core of the transformer 3 becomes saturated, and the current 11 increases rapidly. Unbalanced magnetism occurs.

If the DC load 7 is a load that short-circuits at high voltage, such as the electronic bee 1 or a gun, a large current will flow due to the short-circuit, so
Even if the control angles α and β are slightly different, the biased magnetism described above will occur, and it is necessary to eliminate this problem reliably and quickly.

This invention has been made to solve the above-mentioned problems, and its "1 object" is to provide a power supply device that can reliably prevent biased magnetization of a transformer by a simple means.

[Means to solve the problem]

In order to achieve the above object, the present invention inserts a DC branch capacitor between the relay power regulator and the transformer.

[Effect]

In this invention, when a DC component is generated in the output of the thyristor power regulator, this DC component is cut off by the condenser and does not flow into the transformer, thereby preventing biased magnetization of the transformer.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, 11 is a three-phase AC power supply, 12 is a three-phase thyristor power regulator, and R sum power regulators 2R, S
It consists of a phase power regulator 2S and a T-phase power regulator 2T. 13
is a three-phase transformer, and 14 is a 3+IJ full-wave rectifier. 15
R, 15s, 15T are capacitors, and transformer 1
3 and the R-phase power regulator 2R, S-phase power regulator 2S, and T-phase power regulator 2T. 1
6R116s, ], 6T is a phase angle controller, which controls the deviation ε between the voltage command V″ and the voltage feed hask Vr.
is entered. GRo, G□ are gate signals for thyristors A and B of the R-phase voltage regulator 2R, CSa, G, B
is the data 1 signal appearing on the thyristors A and B of the S-phase power regulator 2S, and GTA% GTR is the gate signal for the thyristors A and B of the T-phase power regulator 2T. The other configurations are the same as those in FIG. 2, and are designated by the same reference numerals.

In this configuration, a thyristor A forming a pair of an R-phase power regulator 2R, an S-phase power regulator 2S, and a T-phase power regulator 2T,
When the control angles α and β of B are equal, the above-mentioned DC component does not occur, and the one-cycle time integral value of each phase current becomes O, and no biased magnetization occurs.

Now, for example, as explained in FIG. 2 above, the control angle α of thyristor A constituting the R-phase power regulator 2R deviates slightly from the control suppression angle β of thyristor B, and becomes α<β. Although a direct current component is generated, the capacitor 15R absorbs this direct current component and no direct current component flows into the transformer 13, so that no biased magnetization occurs. The same applies to the S phase and T phase.

〔Effect of the invention〕

As explained below, this invention prevents biased magnetization of the transformer because when the alternating current whose phase is controlled by the thyristor power regulator includes a direct current component, this direct current component is cut by the capacitor and does not flow to the transformer. Therefore, it is extremely suitable for use in short-circuited large current loads such as electron beam guns.

[Brief Description of the Drawings] Fig. 1 is a circuit diagram showing an embodiment of the present invention, Fig. 2 is a circuit diagram showing a conventional power supply circuit, and Fig. 3 is an output waveform diagram of the thyristor voltage regulator in the above conventional example. It is. 2R ~ 2T - power regulator, 12 - thyristor voltage regulator, 1.3 - three-phase transformer, 14 - full wave rectifier, 7 - load,
9-voltage command unit, 10-error amplifier, 15R~15T-
Capacitor, 16R-16"l" phase angle controller.

Claims (1)

[Claims] A power supply device comprising a phase-controlled thyristor power regulator, a transformer that transforms the output of the thyristor power regulator, and a rectifier that converts the output of the transformer into DC and supplies power to a DC load, the thyristor power regulator and A power supply device characterized in that a capacitor for cutting a DC component is inserted between the transformer and the transformer.