Limited authority self tuning control and applications

In an attempt to provide more reliable self-tuning and adaptive control systems the concept of limited authority adaptive control has been introduced. This involves a generalisation of particular solutions that have been employed in some industrial problems. Rather than identifying the total system description and then calculating a general controller the limited authority control structure has a much more restricted limit. Only certain gains and time constants within the controller structure are adapted. This enables a simple computational algorithm to be produced where the performance is more predictable. The advantages of limited authority adaptive control are introduced and a power systems application is described. The problem considered is the regulation of alternator voltage in electrical power systems. Both simulation and power station trial results are presented and a brief overview of the theoretical basis for the solution is provided.