An electron-beam accelerator based on spiral water pulse forming line which consists of a primary storage capacitor system, an air core spiral strip transformer, a spiral pulse forming line of water dielectric, and a field-emission diode, is described. The experimental results showed that the diode voltage is more than 500 kV, the electron beam current of diode is about 24 kA, and the pulse duration is about 200 ns. The main parameters of the accelerator were calculated theoretically. The distributions for electrical field in the pulse forming line were obtained by the simulations. In addition, the process of the accelerator charging a spiral pulse forming line was simulated through the Pspice software to get the waveforms of charging voltage of pulse forming line, the diode voltage and diode current of accelerator. The theoretical and simulated results agree with the experimental results. This accelerator is very compact and works stably and reliably.

A high voltage pulse Tesla transformer with a coupling coefficient of 0.75 was designed and experimentally investigated. The transformer was employed to charge a spiral water pulse forming line (PFL) in a high current electron beam accelerator, and was featured by its compactness, stability, and reliability. When the primary input voltage is 55 kV, the transformer can charge the PFL to 720 kV with an energy conversion efficiency of 36%. The formulas for calculating the primary and secondary inductances of the transformer were deduced, with which the main parameters of the transformer were calculated theoretically. The distributions for electrical and magnetic fields in the transformer were obtained by the simulations of calculation. In addition, the process of an accelerator of the transformer charging a spiral PFL was simulated through the Pspice software to get the waveform of charging voltage, the diode voltage, and diode current of accelerator. The theoretical and simulated results agree with the experimental results.

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