PENDEKATAN MODEL ZHANG DAN HAYDEN DALAM KAJIAN LISTRIK BUAH JERUK GARUT

Studies of citrus properties based on electrical measurement have been done using low alternating current signal. The electrical conductance and capacitance of Garut citrus have been investigated on frequency variation from 50 Hz to 1MHz. The cell systems have been made from acrylic and electrode plate conductor of cuprum. The sample of citrus placed between the electrodes, as dielectric material. Hi LCR Tester Hioki 3532-50 with dual probe (modified from four probes) used to measure sample electricity. This equipment provided with the current source which its frequency earn variation. The electrical circuit modeling for Garut citrus fruits has been investigated by comparing the results of experiment with electrical modeling circuit configurations. This approach developed using circuit modeling of resistors - capacitors which match to the experiment data. The electrical circuit constructed from a series and parallel configuration that refers to the condition of citrus fruit. The model adopted from kiwifruit and eggplant based on Equivalent circuit models proposed by Hayden et al.(1969) and Zhang et al. (1990). At the certain parameters of resistor and capacitor which representation of internal fruit, data modeling simulation results have a high compatibility. Modeling of electrical impedance spectroscopy results has profile shapes that are similar to the results of direct experimental measurements. Electrical conductance of Garut citrus increases exponentially while the impedance and capacitance decreases exponentially when the frequency is raised. The Zhang model was better than model adopted from Hayden. Keyword: Conductance, Capacitance, impedance, Garut citrus.