New approach for the design of pole placement power system stabilizers

Pole placement power system stabilizers (PSS) are well known for their superior performance when compared to the conventional lead-lag stabilizers. They require feedback of all the state variables which are generally not measurable. In multi machine systems pole placement designs require feedback of other machine states as well. This paper proposes a new approach for the pole placement based PSS. In this paper, recently proposed modified Heffron Phillip´s model is used for the PSS design. It is derived by taking the secondary bus voltage of the step-up transformer as reference instead of infinite bus. State variables of this model are locally measurable, which makes the pole placement design decentralized. The performance of the proposed controller is evaluated on a single machine infinite bus system over a wide range of operating conditions. The proposed PSS performance is found to be better than the conventional PSS.