To meet the requirements of plasma sewage treatment

we designed a compact and highly repetitive nanoseconds-scale pulsed power modulator based on Marx generator. The power modulator uses IGBT as the main discharge switch with the driving signals provided by multiple output magnetic ring transformer. The Marx generator is composed of 25 stages. Each stage consists of IGBT switch

fast-recovery diode

and capacitors. In the charging process

the capacitor is charged through an inductor and diodes

which leads to high charging speed and low power loss. While in the discharging process

the inductor can act as an isolator between the DC input and the high voltage pulse output. In order to protect the IGBT switches from short circuit

the over-current protection is utilized. The experimental results show that when the input voltage is 500 V

the proposed generator in the presence of series-connected 25 Marx unites can generate a fast output pulse with 10 k V-voltage

400 ns-minimum pulse width

and 50 ns-rise time. In this case

the gas in reactor can be corona discharged

and thus the sewage can be purified rapidly.