Preliminary Research on Primary Energy Source of High Current Electron Beam Accelerator Based on Spiral Pulse Forming Line

In this paper,the primary energy source of high current electron beam accelerator based on spiral pulse forming line is investigated.It consists of the constant-current power supply,the high voltage pulse capacitor,the field distortion switch,and the protection system.The primary energy source can discharge to the primary winding of the transformer with high voltage pulses whose amplitude of voltage is 40kV,current is 80kA,pulse width is 8μs and repetition frequency is less than 5Hz.The primary energy source is applied to a high current electron beam accelerator, and is featured by its compactness,stability and reliability.

Experimental Study of the Recovery Times of Spark Gap Switch with Different Gases

A two-pulse method is used to determine the insulation recovery time of the gas spark gap switch with different types of gas applied in a high power accelerator with a water dielectric pulse forming line. At the breakdown voltage of 450 kV, with the vacuum diode voltage of about 200 kV, and a current of 30 kA, recovery characteristics of H2, N2, SF6 were studied. The recovery percentages of the gas breakdown voltage and vacuum diode voltage were determined. The results show that hydrogen has the best recovery characteristics. At a pulse interval of 8.8 ms, the recovery percentages of both the gas breakdown voltage and vacuum diode voltage for hydrogen exceed 95%. For SF6 and N2 with an interval of 25 ms and 50 ms respectively, a 90% voltage recovery was obtained. The experiments also proved that the repetitive rate of the high power accelerator with a pulse forming line is mainly restricted by the gas switch repetitive rate; the recovery percentages of the vacuum diode voltage are limited by the recovery percentages of the gas switch breakdown voltage. The hydrogen switch can be employed for a high repetitive rate-high power accelerator with a pulse forming line.