Abstract
The underwater pulsed arc discharge is one of the effective methods in water treatment applications. In pulsed arc discharge, a pulsed output in the range of 1-10 kV is typically applied across the water treatment chamber electrodes with a gap of several millimeters range between these electrodes, while the pulsed load current is above 1kA. The employed pulse generator should not only be capable of generating a high-voltage level, but also withstand the corresponding high-current stresses. In this paper, a multi-module high-voltage pulse generator is proposed for pulsed arc discharge-based water treatment system. The proposed generator consists of n synchronized groups fed from isolated dc sources, while their outputs are connected in series forming a high voltage pulsed output. Each group consists of m parallel-in parallel-out identical synchronized modules to share the current. Each module consists of a boost converter followed by a Capacitor-Diode Voltage Multiplier (CDVM) which is followed by chopping Insulated Gate Bipolar Transistor (IGBT). Each module is controlled to ensure a regulated dc output voltage across its terminals, a sinusoidal input grid current, and unity input power factor. In the proposed scheme, relatively low-voltage low-current IGBTs and diodes can be employed to generate the high-voltage high-current pulsed output. The simulation results for a 30kW system are presented to show the viability of the proposed approach.