JPS63195712A - Control system for acceleration power supply - Google Patents

Abstract

PURPOSE:To obtain a compact circuit together with reduction of the cost by controlling the voltage rise characteristics of an acceleration power supply based on the rise characteristics of an arc current. CONSTITUTION:When a switch 13 is closed, the current I of a constant current source 11 always flows through the switch 13 and no arc current iA flows. When the switch 13 is opened, the current I is shunted to a capacitor 15 and a load 14. In such a case, the current iA rises up in an exponent function curve of a time constant CR4 (C: capacity of the capacitor 15). When a switch 21 is closed at a time point t1, the voltage of a reference voltage generator 22 is applied to the input Y of a function generator 20. The generator 20 receives the information CRA on an arc power supply through the other input X. Then the generator 20 functions as the reference signal of an automatic control circuit 19 by an output Z serving as a proper function. A vacuum tube 17 controls the voltage Vacc of an output terminal 23 so that the other input of the circuit 19, i.e., the signal of a voltage divider 18 is coincident with the reference signal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a control system for a power supply for a neutral particle injection device for heating fused plasma.

(Prior art) The power source for the neutral particle injection device for nuclear fusion plasma heating (hereinafter referred to as NBI) has various power sources for driving NBIt, and the arc power source and acceleration power source are one of these power sources. Generally consists of a DC power supply circuit.

In order to achieve good beam injection for NBI, the arc current startup characteristics are the most important factor. It is necessary to select the characteristics.

Conventionally, for this purpose, the step-like arc current shown in FIG. 2 was obtained by turning on and off each switch according to the rising characteristics of the accelerating voltage using the arc power supply circuit shown in FIG.

Fig. 1 is a circuit diagram showing an example of a conventional arc current, in which 11 is a constant current power supply, J, 2J, 122°123...n
1 is a resistor, 131, 132, 133...n2 is a switch, and 14 is a load.

Figure 2 is a waveform diagram explaining the operation of the circuit shown in Figure 1. (,) is the current waveform of the arc current flowing through the load 14''Ik shown in Figure 1. (b) is the current waveform of the accelerating power source. This shows the voltage waveform of the switch 131 on the current side to.
, 132, 133... n2 are all closed, and the arc current i at this time is the value of equation (1), and the hook)
) has a sufficiently small value compared to the current in the tube.

Here, ■ is the current value of the constant current power supply 11, and Rm is the current value of the load 14.
The resistance value, R, is the resistance 121, 122, 123...n
1 is the parallel combined resistance value of all. From this state, the voltage trice of the acceleration power source starts to rise at time t1. The rise of the voltage '17acc as shown in FIG.
By sequentially opening the switches 32 and 32, the arc current rises each time each switch is opened, and the desired rise characteristics can be obtained by changing the timing of opening each switch and the number of switches. Can be done.

(Problems to be Solved by the Invention) However, in order to accurately control the rise of the arc current im, it is necessary to use a large number of switches, and each switch must be controlled to open and close independently. from,
The drawback is that the control circuit becomes very complex and large.

An object of the present invention is to eliminate the above-mentioned drawbacks, and to reduce the size and cost of an arc source. The object of the present invention is to provide a control method for an accelerating power source that enables good beam incidence while maintaining the same.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve this object, the present invention provides a power source having an acceleration power source and an arc power source, in which the output signal of the reference voltage generator of the acceleration power source is set to a predetermined value. The present invention is characterized in that a voltage reference signal of the acceleration power source is calculated by performing a function conversion from an arc current that changes according to a function of , and the output voltage of the acceleration power source is controlled based on the voltage reference signal.

(Function) In the present invention having such a configuration, the voltage start-up characteristics of the accelerating power source are controlled based on the start-up characteristics of the arc current, so the arc power source does not require a large number of switches and complicated It becomes possible to reduce the size and cost of multiple circuits that do not require a control circuit.

(Example) The present invention will be explained below with reference to FIGS. 3 to 5.

FIG. 3 shows an integrated power supply circuit according to the present invention.
The same symbols as in FIG. 1 indicate the same elements, 13 is a switch, and 15 is a capacitor.

Figure 4 (&) shows the arc current (mu) according to the present invention;
b) Shows the voltage waveform of the acceleration power source. At the current side to, the switch 13 shown in FIG. When the current Iti of the constant current power supply 11 is shunted to the capacitor 15 and the load 14, it flows.At this time, the arc current (m), if the capacitance of the capacitor 15 is C, rises by drawing an exponential curve of the time constant of CXRm. Becomes a characteristic.

This ζ is the voltage of the acceleration power supply! tea is determined by controlling the voltage ``ae (! good.

FIG. 5 shows a configuration diagram of the accelerating power source, in which 16 is a high voltage DC power source, 17 is a vacuum tube, and 18 is a voltage divider.

19 is an automatic control circuit, 20 is a function generator, 2 is a switch, and 22 is a reference voltage generator. In FIG. 5, when the switch 21 is closed at time t1, the voltage of the reference voltage generator 22 is applied to the input YK of the function generator 20. The function generator 20 receives the information CXRm of the arc power supply from another input X, and generates the automatic control circuit 1 from the output 2 as a suitable function.
It operates as a 90 standard signal. The vacuum tube 12 adjusts the voltage jJ&ee at the output 23 so that the signal of the other input of the automatic control circuit 19, namely the voltage divider 18, coincides with the reference signal. In this way, by controlling the voltage profile of the accelerating power source in accordance with the rise characteristics of the arc current, it is possible to achieve good beam incidence.

[Effect of the invention] In the configuration diagram of the accelerating power source shown in FIG.
The circuit excluding 0t is a necessary configuration for conventional accelerating power supplies, but in the present invention, a function generator 20 is added to the accelerating power supply to maintain the rising characteristics of the arc current im constant. Since the voltage of the accelerating power source can be controlled so as to obtain an appropriate relationship with the above characteristics, it is possible to provide a control method for the accelerating power source that enables simplification, miniaturization, and cost reduction of the circuit.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing an example of a conventional arc power supply, Figure 2 is a waveform diagram explaining the operation of the circuit shown in Figure 1, and Figure 3 is a waveform diagram illustrating the operation of the circuit shown in Figure 1.
4 is a waveform diagram illustrating the operation of the circuit shown in FIG. 3, and FIG. 5 is a configuration diagram of the accelerating power source of the present invention. 11... constant current power supply, 13... switch, 14...
・Load, 15... Capacitor, 16... High voltage DC power supply, 17... Vacuum tube, 18... Voltage divider, 19...
Automatic control circuit, 20... Function generator, 21... Switch, 22... Reference voltage generator, 121, 122, 1
23...nl...Resistance, 131, 132, 133.
...nl...switch. Applicant's agent Patent attorney Takehiko Suzue Figure 1 1Δ Sailor No. 21! l Figure 3 tOt+ 4th cause 5g! A

Claims (1)

[Claims] In a power source having an accelerating power source and an arc power source, a voltage reference signal of the accelerating power source is calculated by converting the output signal of a reference voltage generator of the accelerating power source from an arc current that changes according to a predetermined function, and calculating the voltage reference signal of the accelerating power source. A control method for an acceleration power source, characterized in that an output voltage of the acceleration power source is controlled based on a signal.