| Abstract: | Transient response and tracking characteristics of three adaptive identifiers are illustrated and compared experimentally through digital simulation. Focus is placed on series-parallel (SP) identifiers, with and without auxiliary error signals. The identifiers are algorithms which have adjustable coefficients and are designed to follow the process output. At each computational cycle, the coefficients of the identifier (and the error signals) are updated in response to the tracking error between the process and identifier outputs. The process is simulated on an EAI TR-20 analogue computer, and the identification algorithms are implemented on a PDP-11/40 minicomputer. Testing is distributed over three processes commonly encountered by the control engineer. Variable adaptation gains, which are positive functions of the absolute value of the tracking error, accelerate the convergence of the identifiers. The experimental results are summarized in terms of the computational requirements of the identifiers. |
