Simultaneous and coordinated tuning of PSSs and PODs using differential evolution

Tuning Electric Power System (EPS) controllers for small-signal enhancement is a very hard task. Nowadays, the most used techniques for this task involves a trial-and-error process. These techniques consider a set of operating conditions of the system and multiple modes of oscillation, making it very difficult for a human designer to keep track of so many variables and parameters. This results in a sequential approach, where one controller is tuned, placed in the system, and then the designer proceeds to tune the next controller. This paper proposes a method for simultaneously tuning controllers considering several operation conditions at once. The tuning is done in a coordinated way, avoiding interactions among the controllers. A differential evolution technique is used to perform the automatic tuning method proposed in this work. One important point to remark is that this algorithm can tune different types of controllers at once (PSSs and PODs in this case). Results show satisfactory performance of the tuned controllers, showing the effectiveness of the proposed technique. Furthermore, a significant productivity gain can be achieved if the engineer in charge of this design only supervises the automatic process, instead of performing all the calculations himself/herself. This is one of the main contributions of the present paper.