This paper represents a step toward shooting an optimal robust three-parameter power system stabilizer (PSS) with the common form of $(x_1+x_{2}s)/\left(1+x_{3}s\right)$. The whole set of stabilizing PSSs is graphically characterized using d-decomposition with which the controller-parameter space is subdivided into root-invariant regions. Design is accomplished using the bench mark model of single machine-infinite bus system (SMIB). Rather than Hurwitz stability, d-decomposition is extended to consider d-stability where D refers to a pre-specified damping cone in the open left half of the complex $s$-plane to enhance time-domain specifications. Pole clustering in damping cone is inferred by enforcing Hurwitz stability of a complex polynomial accounting for the geometry of such cone. Parametric uncertainties of the model imposed by continuous variation in load patterns is captured by an interval polynomial. As a result, computing the set of all robust d-stabilizing PSSs calls for Hurwitz stability of a complex interval polynomial. The latter is tackled by a complex version of Kharitonov's theorem. A less-conservative and computationally effective approach based on only two extreme plants is concluded from the geometry of the stability region in the controller parameter plane. Simulation results affirm the robust stability and performance with the proposed PSSs over wide range of operating points.

本文代表了迈向具有通用形式的最优鲁棒三参数电力系统稳定器（PSS）的一步。 $（X_{\mathrm{1个}}+X_{2}s）/（\mathrm{1个}+X_{3}s）$。稳定化PSS的整个集合使用d分解进行图形化表征，通过该分解可将控制器参数空间细分为根不变区域。使用单机无限总线系统（SMIB）的基准模型完成设计。d-分解扩展到考虑d-稳定性，而不是Hurwitz稳定性，其中D表示复合体左半部中的预先指定的阻尼锥。$s$平面以增强时域规范。通过加强复杂多项式的Hurwitz稳定性来推断阻尼圆锥中的极点群集，该多项式考虑了该圆锥的几何形状。由载荷模式连续变化引起的模型参数不确定性由间隔多项式捕获。结果，计算所有鲁棒的d稳定PSS的集合需要复数间隔多项式的Hurwitz稳定性。后者通过Kharitonov定理的复杂版本解决。从控制器参数平面中稳定区域的几何形状得出了仅基于两个极端工厂的保守性较低且计算效率较低的方法。仿真结果证实了所提出的PSS在较宽的工作点范围内的鲁棒稳定性和性能。