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With the development of pulsed power technology and the expansion of its application areas, the requirements for pulsed high-voltage supplies are getting sophisticated. Many researchers are exploring new circuits or trying to improve the performance of the existing circuits. In this study, we introduce a variant circuit of the Marx generator based on hybrid energy storage (HES). This circuit topology, referred to as the LCL circuit in this article, allows two inductors and one capacitor to discharge simultaneously to obtain a higher output voltage. By observing the simulation results, we compared the performance of this proposed circuit with circuits based on other energy-storage methods, including capacitive energy storage (CES), inductive energy storage (IES), and the previously studied HES. After confirming the operation process of an LCL module, a two-stage experimental circuit has been built using power MOSFET switches for carrying out the verification experiments. With a charging voltage of 800 V, the output voltage of $\sim $ 8.4 kV with a rise time of $\sim $ 30 ns has been obtained on a 200- $\Omega $ load. The voltage addition of two modules has indicated the potential of a Marx circuit for a much higher output voltage.

Pulsed gas discharge has been studied using a pulsed power generator with a bipolar solid-state linear transformer driver (SSLTD) scheme. Taking advantage of the output flexibility of the bipolar SSLTD, we have studied the residual charges phenomenon by the coaxial discharge load. The experiment result shows that for two consecutive positive pulses discharge, the current of the second positive pulse is usually lower than that of the first pulse for the same voltage amplitude. However, a middle negative pulse applied between the first and second pulse can increase the current of the second positive pulse. An explanation for this phenomenon has been explored using a 1-D model that considers the effect of residual charge left by the previous pulse discharge. According to the explanation of our 1-D discharge model, this phenomenon may be caused by the residual charge distorting the discharge electric field strength. The findings obtained by this article will help us understand the fundamental characteristics of pulsed atmospheric pressure gas discharge.

In this study, the effects of pulse waveform characteristics on the production of OH radical under atmospheric pressure in a water treatment system have been studied. A solid-state linear transformer driver (LTD), which is capable of generating pulsed power with various waveforms, was used in these experiments. In order to investigate the effect of voltage at the last phase of pulsed streamer discharge on production of OH radical, the nanosecond pulse was separated into two parts, the first part and the last part, and the production of OH radical was evaluated by changing the voltage of last part under condition of the same average input power. As a result, when the voltage of the last part of the pulse is suppressed, the OH radical production yield increased, which means inefficient at the last phase. Then, to evaluate the phenomenon at the last part, the OH radical production yield at the last part only was also measured. The yield increased with an increase of the voltage at the last part. It proves that one of the reasons of inefficiency of the production yield at the last phase is electric field reduction after the primary streamer.

For pulsed power generation, the energy storage unit is one of the most fundamental components. The common energy storage methods in the current pulse power systems are capacitive energy storage (CES) and inductive energy storage (IES), each with its own advantages and disadvantages. In this study, we have tested a circuit using both CES and IES, which we refer to as a hybrid energy storage (HES) approach. Compared with a CES or IES system, the output characteristics of an HES system show potential flexibility given by two free parameters $\rho $ , which corresponds to the impedance relation between the source and the load, and $\sigma $ , which corresponds to the initial relation between CES and IES. By using a five-module solid-state Marx circuit, an HES-based pulsed power generator has been demonstrated. In each module, power MOSFETs are used as switches for controlling the initial energy ratio between the capacitor and the inductor, before allowing both of them to release their energy to the load simultaneously. The results have characterized HES as the third choice for energy storage of pulsed power systems, after CES and IES.

This paper presents the experimental results of static and dynamic characteristics of the newly developed 14 kV 4H-SiC high-speed drift step recovery diode (DSRD) for pulse power applications for the first time. The feature of the diode structure is to be designed based upon the p+/p-/n+ structure and is to make an additional extremely low doping and thin n-drift layer between the p-drift layer and n+ substrate. This device successfully exhibits higher breakdown voltage of 14kV and high-speed voltage pulse in a range of a few nanoseconds, simultaneously.