Frequency-Response Analysis for Industrial Automatic-Control Systems

The authors outline the fundamental principles of frequency-response analysis in terms familiar to the industrial automatic-control engineer, as well as present data obtained by frequency-response methods descriptive of the effect of typical variables on the behavior of the control system. These variables are gain, derivative time, reset rate, transportation lag, and capacity lag, with period of oscillation and stability as dependent variables. They have been combined to form three basic controllers and four basic processes, the data being presented for the various combinations of controller and process. The method of calculation and a specific example are given in the Appendix.