Biological Effects of Pulsed Electric Field by Several Ways of Applying Voltage

To study the biological effects of pulsed electric field by several ways of applying voltages several types of pulsed power generators were designed. We built pulse forming line (PFL) and pulse forming network (PFN) to provide a usual rectangular single pulse. Bi-polar pulse generators (BPG) were designed to compare the effects of single rectangular pulse. BPG generates two rectangular pulses of same amplitude with same pulse duration in series but one is positive and another is negative and it has no zero-frequency components. RLC circuits were also built to apply another type of pulse, a damping oscillation, to the load. The frequency components of these three generators are completely different. By using them some experiments on the aquatic species have been performed and the experimental results show different tendencies by different pulse shapes. A repetitive pulsed power generator (RPPG) using MOSFET was built to study the effects of accumulation of pulses. The experimental results by RPPG show that when the time interval between 2 successive pulses is less than 2 ms the same effect as a single pulse with double pulse width can be achieved. Other results show the effects of accumulation pulses.