A Rapid Parameter-Tuning Strategy of Plug-and-Play DC Distribution Systems Based on Fast Parameter Boundary Calculation

Plug-and-Play (PnP) capabilities are of significant relevance to enhance the resilience of DC distribution networks. During the device plug-in and -out, small-signal stability issues may arise due to the inappropriate system parameters, and therefore, rapid stability analysis and adjustment are essential before performing the PnP operations. This paper presents a three-stage strategy to rapidly improve small-signal stability by tuning few parameters. In the first stage, a novel indicator, the projection of eigenvalue parametric sensitivity (PEPS), is proposed to locate dominant parameters affecting stability. Then, rapid parameter boundary calculation is adopted as a less time-consuming alternative for drawing root loci in the second stage to adjust the selected parameters. Firstly, for boundary calculation of control parameters, the Eigenvalue Perturbation Theory (EPT)-based method is speeded up by reducing the order of the auxiliary matrix. Plus, the irrelevant eigenvalues of the auxiliary matrix are excluded first to improve the method's reliability. Secondly, the Secant-based iteration method is adopted to rapidly determine the security boundaries for operating parameters. System stability is finally rechecked in the third stage. Numerical and simulation results indicate that the proposed strategy can adjust system stability within the security margin, only taking a fraction of the time of conventional methods.