Multivariable Control of Bath Recovery Plant for Aluminium Electrolysis

Abstract

The paper describes a time-varying, non-linear, sampled-data multivariable control problem with human and laboratory interfaces between the process and controlling computer. Special emphasis is placed on the plant experience and physical reasoning which enables the problem to be gradually reduced to a sample-by-sample-adaptive one with a particularly simple feedforward/feedback solution. It is concluded that extra effort spent in setting up and simplifying a control problem can pay enormous dividends in terms of (a) physical insight into the most important aspects of the process from the control viewpoint, and (b) the ease with which the design problem is solved.