Stability of linear systems with transport lag

A method is presented whereby the absolute and relative stability of linear control systems containing transport lag or distributed lag can be determined. The method utilizes a variation of the generalized parameter plane technique as developed by D. D. S̆iljak and all results are in terms of two free system parameters. An example of a particular system with transport lag is analyzed. In the example, the system stability is analyzed with respect to the simultaneous variation of a controller gain and time constant.