Pole assignment design of the Power System Stabilizer by phase compensation method

The small-signal angular stability problem caused by insufficient damping of low-frequency oscillations threatens the security and integrity of power grids. An effective way of suppressing oscillations has been through auxiliary controllers, which form power system stabilizers (PSSs), installed alongside generator excitation system to provide assisted damping. General PSS designs include the phase compensation and pole assignment methods. One accurate approach in this paper is proposed to set parameters of a PSS to achieve pole alignment using the phase compensation method. The required damping contribution of the PSS is calculated firstly from the design target obtained from the pole assignment method. Parameters of the PSS are set which satisfy the required damping contribution using the phase compensation method. Thus, oscillation modes are assigned accurately to the required position. This paper demonstrates that the proposed PSS method can effectively suppress identified low frequency oscillations and limit the impact on small-signal stability.