A rectangular pulse Marx generator with an adjustable dead time drive circuit
Jie Deng, Yuyu Zhu, Lu Zhang, Haoran Li, Yue Pan, Yuheng Gao, Shunqiang WanA rectangular pulse Marx generator with an adjustable dead time (DT) drive circuit is presented. The proposed topology introduces a load-side discharge path to provide a controlled low-impedance route for removing the residual charge stored in the load-side parasitic capacitance during turn-off, thereby improving the falling-edge transition. Meanwhile, the series-connected discharge path structure prevents a single spurious turn-on event from directly forming a local low-impedance path, thereby reducing the probability of short-circuit path formation. To coordinate the discharge and charge switching actions, an RC-delay-based magnetic drive circuit is developed, enabling continuous DT adjustment from 0 to 200 ns. In addition, a resistor–capacitor–diode (RCD) voltage-balancing circuit is designed for the series-connected charging metal–oxide–semiconductor field-effect transistors. Experimental results show that the maximum voltage deviation from the ideal value is reduced from more than 66% to about 10%. An eight-stage prototype generates ∼5 kV from a 650 V input with a 20 kΩ load. Without the RCD voltage-balancing circuit, the measured rise and fall times are ∼48 and 72 ns, respectively. After introducing the RCD voltage-balancing circuit, the rise time increases to ∼60 ns due to the additional capacitance, while the fall time remains nearly unchanged. The output pulse width is continuously adjustable from 2 to 10 μs, and stable operation at 10 kHz is demonstrated. These results verify that the proposed generator is effective for reliable high-voltage rectangular pulse generation with adjustable DT and improved voltage balancing.