Rapid Individual Parameter Optimization of Plug-and-Play Modules in DC Active Distribution Networks Considering Virtual Impedance

Plug-and-Play (PnP) operations are commonplace to enhance the resilience of DC Active Distribution Networks (ADNs). During device PnP, small-signal stability issues may arise due to inappropriate system parameters. Therefore, rapid stability adjustment is essential to realizing PnP operations. This paper presents an Individual Parameter Optimization (IPO) method to rapidly improve stability by tuning few parameters. Virtual Impedances (VIs) are considered to solve the problem that adjusting the regular operating parameters is limited or inoperable in practice. Rapid parameter boundary calculation is adopted as a less time-consuming alternative for drawing root loci to select appropriate values of dominant parameters. Firstly, for boundary calculation of control parameters, a method for distinguishing all types of root loci is proposed based on the first- and second-order Eigenvalue Parametric Sensitivities (EPSs), and then, according to different root loci, narrower initial intervals are determined to speed up Eigenvalue Perturbation Theory (EPT)-based method. Secondly, for adjustable operating parameters, the improved EPT-based method is adopted instead of the Newton-Raphson formula in traditional iteration methods to avoid solving eigenvalue problems and shorten the calculation time of EPSs. Numerical and simulation results indicate that the proposed IPO method can effectively adjust system stability, only taking a fraction of the time of traditional methods.