Effects of Electrode Systems on Numerical Estimation of Internal Human Body Impedance at Power Frequency

Internal body impedances Ri of an anatomically realistic human model were numerically calculated at 60 Hz under various current scenarios and electrode sizes. On the basis of the numerical results, the effects of electrode systems on Ri were investigated. It is found that Ri obtained for a two-electrode model are larger than those for a four-electrode model by a factor of up to about 1.3. This means that the body impedances measured by using the four-wire method are smaller than the calculated ones by up to about 23%. At the end, it is concluded that, although the difference in the electrode systems is a cause of the disagreements between the calculated and measured body impedances, its effect is insufficient to fully reconcile the actual disagreements. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.