Simulation Studies for Nonlinear-Transmission-Line Based Ultrafast Rise Times and Waveform Shaping for Pulsed-Power Applications

The generation of high-voltage electrical pulses with very fast rise times is important for several pulsed-power applications. Although several techniques and devices have been used to generate ultrashort rise-time pulses, most suffer from problems relating to reliability, lifetime, and power-handling capacity. Here, the concept of using nonlinear transmission lines is used for attaining ultrashort rise times and pulse sharpening. Numerical simulations are carried out using barium strontium titanate as the dielectric system. The concept is based on using the nonlinear voltage-dependent capacitance of the granular material. The presence of internal grains increases the breakdown strength and also provides for a nonlinear voltage-dependent capacitance that depends on the internal grain size. The output characteristics of transmission lines based on such nonlinear material are simulated. Our results clearly demonstrated rise-time shortening. The results were in agreement with some published experimental data.