Abstract
This paper discusses the material and method of designing the electric circuits of Pulse Electric Field (PEF) hardware that can accommodate Direct Current (DC) voltage with modulation frequencies that could be controlled. The main circuit has several parts that are input, processor, and output. The keypad is used to set the frequency, the duty cycle, the number of Pulse with Modulation (PWM), and time variables. A microcontroller will process these parameters as the processor. The outputs consist of a display, separator, driver, and chamber. The separator is used to secure the processor. The driver is a voltage regulator for the circuit. A PEF chamber is used to treat the sample. The sample used in this study is 40 mL of water for hardware testing. The test procedure is using ± 128 VDC as the voltage source with a variant value of frequency, duty cycle, and time. This test aims to get the best value of these variables that produces optimum condition during the extraction process. Thus, it can be concluded that the hardware is able for the extraction of water-based processes. It can operate over a voltage range from 15 VAC to 128 VAC (up to 172 VDC after rectification), the frequency in 1 Hz to 5 Hz, duty cycle of 1 % to 5 %, and the treatment time in 10 s to 25 min. This PEF hardware design could be used for the microalgae as the water-based raw material by electric shock method.
