A compact pulse generator using diode opening switch for engine gas treatment application

In this paper a compact pulse generator is proposed for NO_x removal system using a corona discharge effect from the exhaust gas of engine cars. A compact pulser based on diodes for opening switches and inductive energy storage has been developed. The pulser consists of a pulse compression circuit including a primary low-voltage stored capacitor, a semiconductor closing switch (a thyristor) as its initial switch, a saturable pulse transformer, and secondary high-voltage circuit including a capacitor, opening diodes, and a resistive load. The experiment results of a proposed pulser with resistance of 200 Omega are following: the voltage amplitude is about 21 kV, the rise time (between 0.1~0.9 of amplitude) is about 21 ns, the pulse width in full width at half maximum (FWHM) is about 42 ns