Experiments of a 100 kV-level pulse generator based on metal-oxide varistor

Area of Science:

• Electrical Engineering
• High Voltage Engineering
• Pulsed Power Systems

Background:

• Metal-oxide varistors (MOVs) offer high energy handling and nonlinear V-I characteristics suitable for pulse shaping.
• Existing pulse generation methods may lack waveform precision or stability under varying loads.

Purpose of the Study:

• To develop and experimentally validate a 100 kV-level pulse generator utilizing MOVs for precise high-voltage pulse generation.
• To investigate the effectiveness of a two-section pulse-forming network (PFN) in conjunction with MOVs for waveform shaping.

Main Methods:

• Circuit simulations were performed using measured MOV V-I characteristics to predict performance.
• A reduced-scale experiment validated simulation predictions.
• A full-scale 100 kV pulse generator with stacked MOVs and a two-section PFN was constructed and tested.

Main Results:

• Simulations indicated a two-section PFN yields superior square pulse definition compared to simple L-C circuits.
• Experimental results closely matched simulation predictions.
• A 90 kV pulse with a 50 ns rise time and 400 ns flat top was achieved into a 50 Ω load.

Conclusions:

• The combination of PFN and MOV is a practical method for generating high-voltage pulses with enhanced flat-top waveforms.
• The developed pulse generator demonstrates stable output voltage despite variations in load impedance.
• Potential applications include surface treatment, plasma generation, industrial dedusting, and medical disinfection.