Design modifications for improved controllability - with application to design of buffer tanks
S. Skogestad

Paper 222e, AIChE Annual Meeting, San Francisco, Nov. 13-18, 1994.

Abstract.
A procedure for analyzing the input-output controllability of single-input single-output (SISO) systems is presented. This procedure is applied to the problem of designing buffer tanks. Although buffer tanks are often introduced for control purposes, they are usually sized in a rather ad hoc manner without explicitly considering the expected disturbances and desired control objectives. It is shown how to use a simple controllability analysis as a basis for a quantitative approach. The main steps are to consider the disturbances and scale the variables properly. Finally, these results are applied to the design of a pH-neutralization process.