JPH0691437B2 - Method of generating large shock current using capacitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention uses a capacitor for suppressing output fluctuation (ripple) of pulse current and energy loss in an impact large current generation circuit using a capacitor. The present invention relates to a method of generating a large shock current.

[Conventional technology]

Conventionally, a circuit as shown in FIG. 4 has been used to obtain a large current pulse having a fast rise and a certain duration after the rise. In this figure, 1 is an energy storage capacitor (hereinafter simply referred to as a capacitor), 2
Is a starting switch, 3 and 4 are inductances and resistances representing the impedances of the capacitor 1 and the starting switch 2, 5 is a load, 6 and 7 are inductances and resistances of the load 5, 8 is a load short-circuiting switch, and 9 and 10 Is an inductance and a resistance that represent the impedance of the short circuit.

An oscillating current is generated by the impedance of the load 5 using the capacitor 1 and the load 5 is short-circuited near the maximum current value by using the load short-circuiting switch 8 to suppress the reversal of the voltage and extend the pulse width. Method is used.

However, according to the above method, an oscillating current is generated between the capacitor 1 and the inductance 9 of the load short-circuiting switch 8 and the resistor 10, and appears as a ripple in the load current. The ripple ratio (η) is almost the same when the value of the inductance 6 of the load 5 is Lo and the inductance 9 of the short circuit is L _CR. It is represented by. Therefore, in order to obtain a fast rising current, the value Lo of the inductance 6 of the load 5 needs to be reduced, so that the ripple ratio η increases. As a conventional technique, for example, as disclosed in Japanese Patent Publication No. 57-34745,
The idea was to reduce the value L _CR of the inductance 9 of the short circuit.

FIG. 5 is a waveform diagram of essential parts for explaining the operation of each part of the conventional circuit of FIG. That is, when the starting switch 2 is turned on at time 0 and the load short-circuiting switch 8 is turned on at time T ₁ , the load current becomes like I ₁ , and the current flowing through the capacitor 1 is I ₂ for load shorting. The current flowing through the switch 8 is I ₃ .

[Problems to be solved by the invention]

With the conventional method of generating a large shock current as described above, the value L _CR of the inductance 9 of the load short-circuiting switch 8 cannot be made zero, so that ripples remain. Also,
In terms of efficiency, the oscillating current component (I _{2 in} FIG. 5) flowing in the capacitor 1 after the load 5 is short-circuited causes a loss due to the resistor 4 of the capacitor 1 and the starting switch 2, resulting in a decrease in efficiency. was there.

The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a method of generating a large shock current using a capacitor with low ripple and high efficiency.

[Means for solving problems]

According to a method of generating a large shock current using a capacitor according to the present invention, a load short-circuiting switch for extending a pulse width of an output current is added to a load in a current generating circuit including an energy storage capacitor and a magnetic field generating load. And a parallel circuit, and using an impact large current generator in which an open circuit switch for disconnecting the energy storage capacitor from the load is inserted in the current generation circuit, a current is supplied to the open circuit switch by starting the load short circuit switch. Of the open circuit switch, the circuit parameter is selected such that the current component generated by the energy storage capacitor and the load short circuit inductance oscillates and inverts its polarity when the load short circuit switch is turned on so as to create a zero point. The open circuit switch is opened when the current flowing in And in which flowed to sustain an impact large current closed circuit with the load short-circuiting switch.

[Action]

In the present invention, the open circuit switch is first closed, and when the load short-circuiting switch is turned on and the current flowing through the open circuit switch becomes zero, the open circuit switch is opened and thereafter the load and the load short circuiting switch are closed. By continuously supplying a large shock current, the output of a large current with a small ripple can be obtained with a small loss.

〔Example〕

 FIG. 1 is an equivalent circuit diagram showing an embodiment of the present invention.

In this figure, the same symbols as in FIG. 4 indicate the same parts,
Reference numeral 11 denotes an open circuit switch, which is provided between the starting switch 2 and the load 5.

Next, the operation of the embodiment of FIG. 1 will be described with reference to the waveform chart of FIG.

As shown in FIG. 2, when the starting switch 2 is turned on at time 0 and the load short-circuiting switch 8 is turned on at time T ₁ , the load current I ₁ , the current flowing through the capacitor 1 and the open circuit switch 11 is I ₂ , The current flowing through the load short-circuiting switch 8 becomes I ₃ . By opening the open circuit switch 11 at time T ₂ when the current I ₂ flowing through the open circuit switch 11 becomes zero, the current I ₁ with less ripple flows through the load 5 thereafter.

A gas blowout type or a circuit breaker using a vacuum tube can be used as the high-current open circuit switch 11.However, in both cases, opening the switch electrode creates an arc and the current continues to flow, shortening the circuit. It cannot be cut off in time. It is necessary to make a condition to break the arc by forcibly setting the switch current to zero, or to consume the arc energy to break the arc. In the present invention, if the circuit parameters are selected such that the current component generated by the capacitor 1 and the inductance 9 of the short circuit when the load short-circuiting switch 8 is turned on vibrate and the polarity is reversed, the current flowing through the open circuit switch 11 will be When the polarity is reversed, a current zero can be created, so that it can be cut off. According to this method, it is not necessary to newly provide an external mechanism to create the zero point of the current. In addition, when the circuit is cut off, an excessive voltage is generally generated between the electrodes, and it is necessary to pay sufficient attention to the problems of withstanding voltage of parts used and re-ignition of the circuit breaker. In the case of the circuit, since the open circuit switch 11 is opened in a state where the inductive load 5 is short-circuited by the load short-circuiting switch 8, the voltage between electrodes is extremely small.

3 (a) and 3 (b) are an equivalent circuit diagram and an output current waveform diagram showing another embodiment of the present invention. In this embodiment, the two capacitors 1 and 21 are connected to the load 5 and are sequentially activated.

In FIG. 3 (a), 22 is a starting switch, 23 and 24 are inductances that represent impedances of the capacitor 21 and the starting switch 22, 25 is an open circuit switch, and others are the same as those of the embodiment of FIG. Is the same.

Next, the operation will be described.

The open switches 11 and 25 are closed beforehand. When the starting switch 2 is turned on (time 0), the start-up current by the capacitor 1 is started. At that time, when the starting switch 22 is turned on at time T ₁ , the second load of the capacitor 21 is applied to the load 5.
The startup current of appears. At the same time open circuit switch 11
An oscillating current determined by the capacitors 1 and 21 and the inductances 3 and 23 flows in the capacitor, and a current zero point can be created, so that the open circuit switch 11 can be cut off.

When the load current becomes close to the maximum value (time T ₂ ) and the load 5 is short-circuited by the load short-circuiting switch 8, the open circuit switch 25 can be cut off thereafter for the same reason as described above. An example of the output current waveform obtained at this time is shown in FIG.

〔The invention's effect〕

As described above, in the present invention, a load short circuit switch for extending the pulse width of the output current is provided in parallel with the load in the current generating circuit including the energy storage capacitor and the load for generating the magnetic field. An impact large current generator is used in which an open circuit switch for disconnecting an energy storage capacitor from the load is inserted in the current generation circuit, and the zero point of the current is created in the open circuit switch by starting the load short circuit switch. When the load short-circuiting switch is turned on, the current component generated by the energy storage capacitor and the load short-circuiting circuit inductance oscillates and the polarity is inverted. Open the open circuit switch, and then close the load and the load short-circuiting switch. Since it flowed to sustain an impact large current within, no output ripple after load short, also the loss of the capacitor and the like is reduced. Further, the open circuit switch of the present invention has an advantage that a new mechanism for interrupting the arc need not be provided, an excessive voltage does not occur at the time of interruption, and an advantage that an ordinary circuit breaker can be used, etc. Have.

[Brief description of drawings]

FIG. 1 is an equivalent circuit diagram showing an embodiment of the present invention, FIG. 2 is a waveform diagram of essential parts for explaining the operation of the embodiment of FIG. 1, and FIGS. 3 (a) and 3 (b). FIG. 4 is an equivalent circuit diagram showing another embodiment of the present invention and an output current waveform diagram, FIG. 4 is an equivalent circuit diagram showing an example of a conventional shock large current generator, and FIG.
FIG. 11 is a waveform chart of a main part for explaining the operation of the conventional example of the figure. In the figure, 1 is a capacitor, 2 is a starting switch, 3,6,9 are inductances, 4,7,10 are resistors, 5 is a load, 8 is a load short-circuiting switch, and 11 is an open circuit switch.

Claims (1)

[Claims] 1. A current generating circuit comprising an energy storage capacitor and a magnetic field generation load, a load short-circuiting switch for extending the pulse width of an output current is provided in parallel with the load, and the energy storage circuit is further provided. Using a high-impact current generator that inserts an open-circuit switch for disconnecting a capacitor from the load into the current-generating circuit, the load-short-circuiting device is configured to create a zero current point in the open-circuit switch by starting the load-shorting switch. When the current flowing through the open-circuit switch becomes zero, the circuit parameter is selected so that the current component generated by the inductance of the energy storage capacitor and the load short-circuit circuit oscillates when the switch is turned on. After opening the open circuit switch, a large impact will occur in the closed circuit between the load and the load short-circuiting switch. Impact high current generation method using a capacitor, characterized in that flowed to sustain the flow.