Design of High Voltage Power Supply System for Application of Electrohydrodynamic Drying

Electrohydrodynamic (EHD) drying is an emerging technique for energy-efficient, non-thermal, and high-quality drying of food and biomaterials. It is based on enhancement of moisture removal from food material under action of electric wind resulting from corona discharge, which is generated when high voltage is applied across two electrodes with different radii of curvature. A high voltage power supply (HVPS) is an important component in experimental set-up for studying EHD drying process. In the present study, an HVPS for EHD drying of food has been developed based on its design, measurement, and control requirements. A flyback or line output transformer was used to generate high voltage up to range of 10 kV (peak-to-peak output voltage). Performance of HVPS was evaluated using current-voltage characteristics and power consumption. Maximum peak-to-peak output current obtained was ~ 450 mA under load of 20 MΩ. Average and root mean-squared power of HVPS ranged from 9 to 26 W and 13 to 35 W, respectively. Cost and weight of HVPS were 5,588 INR and 2.4 kg, respectively. Thus, the designed HVPS offered low-cost and portable solution to generate high voltage for electrohydrodynamic drying. This research will expedite the process for development of electrohydrodynamic dryers for food industry.