Single-Switch Module, Rectangular High-Voltage Pulse Generator with Nanosecond Rise/Fall Times for Transient Plasma Applications

High-voltage solid-state pulse generators are widely used for driving transient plasma reactors, where rectangular pulses with nanosecond rise and fall times are essential for efficient discharge control. Capacitive plasma loads present a major challenge: after turn-off, the low load current causes slow switch commutation and extended fall times. Conventional fall-time control in capacitive plasma loads typically relies on passive dummy loads, which accelerate switch turn-off but cause significant power losses, or an auxiliary high-voltage switch in a half-bridge configuration, which increases cost and system complexity. To overcome these limitations, this paper proposes a compact single-switch module with an active dummy load and energy recovery. In this method, energy is stored in an inductor during the pulse and released after turn-off to charge an output capacitor, thereby reducing the fall time while recovering energy back into the circuit. By employing a high-voltage switch topology based on capacitive coupling and gate boosting, the rise time is significantly reduced. A 10 kV prototype demonstrates nanosecond-scale rise and fall times with substantially lower power dissipation compared to passive methods. The proposed approach combines efficiency, simplicity, and scalability, enabling precise high-repetition-rate plasma pulse generation with improved overall performance.