Characterization of Electrolytic Pot Signal by Autoregressive Model with Exogenous Input

The indirect estimation of the alumina bulk concentration in the electrolyte is important to keep the right operational condition that avoids anode effects and maximizes current efficiency. Vertical Stub Soderberg (VSS) Side Break has a feed cycle every two hours with a fix amount of alumina and the actual feed adjustment is done in a manual daily basis.These feed conditions are very hard to control; based on Prebaked feed control strategy, the resistance control can be slip in two working regions eg. high alumina concentration and low alumina concentration. From the voltage (output) and current (input) signals and based on Systems Identification Theory, the ARX models of the electrolytic pots. The selected transfer functions of the electrolytic pot are used to perform the steady state representation of the resistance working region. Therefore, this paper shows our latest investigation on parametric ARX models that represent the behavior of the plant.