Pulse power supply for regenerating magnetic energy

Abstract

In order to provide a pulse power supply device using regenerating magnetic energy stored in a discharge circuit to a capacitor so as to use it as next discharge energy and supplying a bipolar pulse current with high repetition, a bridge circuit is composed of four inverse-conductive semiconductor switches, a charged energy source capacitor is connected to a DC terminal of the bridge circuit, and an inductive load is connected to its AC terminal. A control signal is supplied to gates of the inverse-conductive semiconductor switches, and a control is made so that when a discharge current rises, is maintained or is reduced, all the gates are turned off, and the magnetic energy of the electric current can be automatically regenerated to the energy source capacitor by a diode function of the switches. Further, a large-current power supply is inserted into a discharge circuit so as to replenish energy loss due to discharge, thereby enabling high-repetition discharge.

Description

TECHNICAL FIELD [0001] The present invention relates to a pulse power supply device for supplying pulse current to an inductive load. BACKGROUND ART [0002] When a large electric current is supplied to an inductive load, pulse power supply devices, in which normally an energy source capacitor charged with high voltage is connected to the load by using switches such as an ignitron, a discharge gap switch and a thyristor so that a capacitor discharge is started, are generally used. [0003] In these discharge switches, diodes called clamp circuits are generally connected to loads in parallel or to capacitors in parallel. After the electric current becomes maximum, a capacitor voltage is inverted and simultaneously the diodes are turned on, and the load current reflows to the diodes. As a result, reverse charging of the capacitor is prevented, and the clamped electric current continuously flows while being attenuated with time constant L / R due to electric resistance of the load. [0004] On...

AI Technical Summary

Benefits of technology

[0010] An operating sequence of FIG. 2 is explained with reference to FIG. 3. Firstly a capacitor 1 is charged so as to have polarity of FIG. 2 (a charging circuit is not shown), and when switches S1 and S2 are turned on, electric charges of the capacitor start to flow to the load. When an electric current becomes maximum and the voltage of the capacitor is negative (forward-direction voltage of a diode), the load current ref lows via the diode and is brought into a freewheeling state, and the load current continues to flow in two parallel lines in a direction where “a path where a main current flows” is written. The characteristics of the switch constitution and the operation are that the electric current in the freewheeling state continuously flows in two parallel lines. As a result, a current carrying capacity of the switches is only half, and thus this example is economical.

[0011] When the switches S1 and S2 are turned off, the electric current in the freewheeling state is cut off, and the capacitor 1 is recharged into the same polarity via two diodes. As a result, the electric current is quickly reduced and when it becomes zero, the diodes prevent reverse current, thereby stopping the electric current.

[0017]FIG. 5 is a diagram illustrating a simulation circuit showing that the energy source capacitor 1 can be replenished with energy by a low-voltage large-current power supply 5 inserted into the discharge circuit, and a waveform as its result. According to the waveform of FIG. 5, the capacitor voltage and the load current rise according to the number of discharges, but this is because when a voltage which is not less than a voltage of a DC resistance is injected from an external power supply, the discharge current rises. When the voltage of the external power supply is increased or decreased in such a manner, the value of the pulse current can be controlled.

Problems solved by technology

Further, gas excitation laser power supply requires high speed rise of a voltage and high repetition, and thus high repetition control is required as discharge power supply.

The energy is wasted and time to wait for the attenuation is required, thereby raising a technical problem of the pulse power supply devices requiring increased capacity and high repetition.

Images