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This paper proposes a solid-state pulsed power modulator (PPM) with fast rising/falling time and high repetition rates to drive pockels cells. Since the proposed circuit is based on the modular structure using silicon carbide (SiC) metal–oxide silicon field-effect transistors (MOSFETs) for bypass devices as well as for main switches, it can achieve fast switching speed and high reliability. In addition, by a control scheme employing the voltage difference, the proposed circuit can accomplish a high repetition rate and short pulsewidth. Design and implementation of 1.8-kV PPMs with repetition rate of 1 MHz and rising/falling time below 6 ns are presented. Also, important issues for the practical use of the SiC-based PPM are discussed. Experimental results from the developed PPMs are shown to verify the proposed works. [ABSTRACT FROM AUTHOR]

This article describes the compact solid-state Marx modulator (SSMM) with a fast rising time and a short pulsewidth based on the modular structure. By stacking of the TO-263-7 packaged silicon carbide mosfets having high voltage and fast switching capabilities, the designed circuit consists of three components, including the Marx capacitor, an on switch for applying pulse to the load, and an off switch to pull down the pulse. The off switch connected in parallel with load is chosen as a mosfet instead of a diode that is used in the conventional Marx generator. Because the off switch provides a discharging path for the stored energy on the parasitic capacitance, it is highly related to the fast falling time. In order to provide complementary driving signal and power for on/off switches, the simple control algorithm with a minimum component count and a reliable drive circuit against the noise are proposed. In addition, the synchronization of all the gate signals and a compact configuration for minimizing the stray inductance are essential to shorten the rising, falling, and pulsewidth. Based on the proposed circuit, the following specifications of the developed SSMM are achieved: the output voltage of 10 kV, the pulsewidth of less than 50 ns, and the rising and falling times of less than 15 ns. [ABSTRACT FROM AUTHOR]

This letter proposes a high output voltage dc–dc converter topology with series stacked converter modules. To implement the proposed modular dc–dc converter structure, output voltage balancing of the modules and simplification of the control circuitry were considered the major design objectives. To achieve voltage balancing between the modules, we proposed a split-secondary transformer winding structure and distributed connections to the rectifier circuit blocks. Each transformer includes two secondary windings, with each wire pair connected to a different rectifier circuit. Consequently, one rectifier receives ac power simultaneously by sharing the secondary windings fed from two different transformers. The proposed method was verified using a modular LCC resonant converter, which is widely employed in high-voltage applications. As a result, the control circuit was simplified by using a single controller to regulate the total output voltage and by applying a compact sensing circuit referenced to the output voltage of the module placed at the lowest grounding point. [ABSTRACT FROM AUTHOR]