Design of self-tuning PID power system stabilizer for multimachine power systems

A self-tuning PID (proportional-integral-derivative) power-system stabilizer (PSS) is presented for improving the dynamic stability of a multimachine power system over a wide range of operating conditions. To maintain good damping characteristics when there is a drastic change in a system operating condition, the gain settings are adapted in real time, based on the continuously measured system inputs and outputs. The proposed self-tuning stabilizer has a decentralized structure and only local measurements within each generating unit are required for the adaptation process. The effectiveness of the proposed stabilizer is demonstrated by an example. Results indicate that, under disturbance conditions, better dynamic responses can be achieved by using the proposed self-tuning PID stabilizer than a conventional stabilizer