The high-power switch plays an important part in a pulse power system. With the trend of pulse power technology toward modularization, miniaturization, and accuracy control, higher requirements on electrical trigger and jitter of the switch have been put forward. A high-power low-jitter corona-stabilized triggered switch (CSTS) is designed in this paper. This kind of CSTS is based on corona stabilized mechanism, and it can be used as a main switch of an intense electron-beam accelerator (IEBA). Its main feature was the use of an annular trigger electrode instead of a traditional needle-like trigger electrode, taking main and side trigger rings to fix the discharging channels and using SF/N gas mixture as its operation gas. In this paper, the strength of the local field enhancement was changed by a trigger electrode protrusion length Dp. The differences of self-breakdown voltage and its stability, delay time jitter, trigger requirements, and operation range of the switch were compared. Then the effect of different SF/N mixture ratio on switch performance was explored. The experimental results show that when the SF is 15% with the pressure of 0.2 MPa, the hold-off voltage of the switch is 551 kV, the operating range is 46.4%-93.5% of the self-breakdown voltage, the jitter is 0.57 ns, and the minimum trigger voltage requirement is 55.8% of the peak. At present, the CSTS has been successfully applied to an IEBA for long time operation.

In this paper, an all-solid-state high voltage trigger generator is developed, which is aimed at triggering a several gigawatts three-electrode spark gap of an intense electron beam accelerator (IEBA). As one of the most important parts for triggering the IEBA precisely, it is developed based on a fractional-turn ratio saturable pulse transformer and a compact six-stage Marx generator. A pulse of rising time 141 ns and amplitude 79.6 kV is obtained on the 1000 Ω dummy load. The trigger is operated at pulsed repetition frequency over 10 Hz for testing its operational stability. The jitter counted from the initial control signal to the falling edge of the pulse is 0.64 ns. In addition, experiments of three-minute continuous repetitive operations at 10 Hz and higher frequency are carried out. The results show that the trigger generator has high stability even in long-time operations. So far, it successfully applies to the main switch of IEBA with a breakdown voltage of over 500 kV, and a total system jitter of 6.7 ns is acquired.

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An all-solid-state microsecond pulsed power system has been tested in this paper. It can produce larger than 50 kV and microsecond-range pulses continuously for more than 9 × 104 shots into a resistive load at a repetition rate of 10 pps. The whole device has accumulatively operated more than 15 000 pulses at 100 Hz and 3 × 105 pulses at 10 Hz. This all-solid-state pulsed power system consists of a repetitive power supply, a four-stage Marx generator, a pulse forming network, and a resistive load. The repetitive power supply of the pulsed power system is calculated and analyzed first, followed by the introduction of the Marx generator and the three-section anti-resonance network. A polymer box of sodium chloride solution is applied as a resistive load with an impedance of 200 Ω. Repetitive experiments showed that this system is able to operate stably at 100 Hz repetition rate without failure.

In the self-breakdown experiment, it is demonstrated that the breakdown stability of 15% SF6/N2 was higher than that of pure SF6 and N2 in the non-uniform field under negative impulse voltages. In this paper, the stable breakdown phenomenon of the gas mixture is studied at the nanosecond scale. The corona process and streamer process of these three gases are investigated by using a high-speed framing camera. The stabilized corona and the abnormal streamer phenomena observed in the gas mixture discharge have a relation to the stable breakdown phenomenon. The stabilized corona is supposed to be the main reason that obstructs the development of negative steamer and stabilizes the supply of photons to the anode. Furthermore, the captured images of the streamer process in the gas mixture show that there is a negative ion sheath between the electrodes. The sheath keeps the corona stabilized near the cathode tip. In addition, photons emitted by the stabilized corona can ionize neutral particles near the anode. The generated photoelectrons and positive ions accumulate near the anode surface. The positive streamer occurs once the accumulation number reaches a certain value. In addition, the photon emission intensity and stability also have an influence on the stability of the positive streamer.