Abstract
This paper presents a high pulsed electric field generator formicrobial inhibition of flowing liquid food in continuoustreatment applications. The proposed pulsed electric fieldgenerator adopts forward/flyback hybrid converter to generate abipolar narrow pulse output voltages. With this circuit structure,the proposed one can reduce voltage stresses of output diodesand switches, resulting in lower cost. It can also reduce voltageslew rate of the switching components at turn-on and turn-offtransitions to avoid noise interference. Additionally, the proposedgenerator uses an active clamp circuit to recover the energytrapped in the leakage inductance of the transformer with highturns ratio. Moreover, a half-bridge inverter is adopted to drivepiezoelectric devices for clearing the inhibiting electrodes. Tosimplify circuit structure of the proposed system, a synchronousswitch technique is used to integrate the switches in the activeclamp circuit and half-bridge inverter to increase conversionefficiency and reduce volume, size, weight and cost. Finally, aprototype with maximum output voltage of 30 kV and repetitionrate of 12 Hz has been implemented to prove the feasibility ofthe proposed pulsed electric field generator.