Power systems continuously experience changes in operating conditions due to variations in generation/load and a wide range of disturbances. Power system stability and voltage regulation have been considered as important control problems for secure system operation over the years. Currently, because of expanding physical setups, functionality, and complexity of power systems, the proper design of automatic voltage regulators (AVRs) and power system stabilizers (PSSs) has becomes more significant than in the past. That is why in recent years a great deal of attention has been paid to the application of advanced control techniques for power systems.
Conventionally, the AVR and PSS design is considered as a sequential design including two separate stages without any coordination. Although it is known that the stability and voltage regulation issues are ascribed to different model descriptions, it has been long recognized that the AVR and PSS have inherent conflicting objectives.
In the present chapter, the necessity for coordination of AVR and PSS designs is emphasized, and three synthesis methodologies to enhance the stability and voltage regulation of existing real power systems without opening their conventional PSS and AVR loops are introduced.
7.1 Need for AVR–PSS Coordination
As mentioned, the AVR and PSS are conventionally designed as two separate stages in the classical sequential synthesis procedure. First, the AVR ...