Simple and reliable model for estimation of methanol cross-over in direct methanolfuel cells and its application on methanol-concentration control

Abstract

A simplified model of mass-transport phenomena on the anodic side of direct methanol fuel cells (DMFCs) is presented, with the objective of estimating the cross-over flux in order to enable feedforward (sensorless) control of anodic concentration in DMFC systems. The effect of parameter uncertainty on the tracking error of the control system is analysed and several models for temperature dependence are proposed. Experimental data on methanol cross-over was gathered in a DMFC system, and the models were discriminated by means of nonlinear regression. The regression results and an initial test run indicate that feedforward control of anodic methanol concentration in DMFC systems is feasible.