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Many research fields need special high-voltage pulses in pulsed power applications, which are different from typical rectangular pulses. In this paper, a high-voltage waveform modulator of two methods using a solid-state Marx generator has been developed and tested. Instead of manufacturing a generator with a specialized structure, the modulator can control a general Marx generator by low-voltage programmable logic devices to produce an irregular but controllable high-voltage triangular pulse with pulse length of ~4.5 μs and peak voltage of ~123 kV.

This paper proposes a novel bipolar high-voltage Marx pulse current generator for inductive load. The paper first analyzes the feasibility and design parameters of the proposed design, and then elaborates the structure design and optimization. IGBT modules build up the 10-stage Marx adder, and the capacitor in each stage is charged by series-parallel resonant voltage converter. A novel compensation strategy is proposed for the energy loss of the inductive load and the characteristics of switching devices. 1 kA peak current bipolar pulse is achieved with 300 ns rise/fall time and 1.5 μs flattop on a 2 μH inductor. Compared with traditional PFN current generator, this solid-state pulse current generator has similar performance while being easier to adjust and is more compact in shape.

Dielectric barrier discharge (DBD) is used in plasma technology with wide applications, such as ozone generation, depollution of gas stream and surface treatment of plastics. Commonly used power supplies for DBD generate sinusoidal voltages with frequency up to 100 kHz. Recent research shows that apart from a primary discharge occurring at the rising front or during the pulse top, a secondary discharge occurs at the end of the falling voltage flank when unipolar square pulses are used. This excitation method of DBDs improves energy efficiency significantly compared with sinusoidal excitation. In this paper, an all-solid-state Marx generator that can generate nearly rectangular pulses with a DBD load is proposed. It operates at an output voltage of 30 kV, a repetition frequency of 1 kHz and 1 kV DC input voltage successfully. Both the rise and fall times are less than 200 ns, and a maximum pulse-width of 1 us is obtained. A transformer isolated gate drive circuit is employed. This prototype has been applied in gas treatment research using DBD. Preliminary experimental results show that it is able to deliver almost rectangular voltage pulse to resistive load and capacitive load. When driving a DBD load, it can output large current at the rising of a pulse.

A newly developed bipolar high-voltage pulse adder with a novel control method is proposed in this paper. The system adopts modularization design; typical full-bridge semiconductor unit is the basis of each stage. Owe to the phase-shifted control method, the pulse adder has the ability of generating fast narrow bipolar high-voltage pulses. The flexible operation of full-bridge units is fully utilized to solve the problems caused by stray capacitance using phase-shifted control method A laboratory prototype was assembled with 6 stages and each stage was composed of IGBTs. The adder can generate 5 kV bipolar pulses with tens of nanoseconds pulse width, and both rise time and fall time are less than 40 ns, the repetition rate is up to 1 kHz. The experimental results are shown in the paper and discussed at last.