基于灵敏度与参数耦合量化分析的柔性互联系统小信号稳定性研究OA

Along with the increasing penetration of power electronics in distribution networks,small-signal stability issues,such as wide-band oscillations,have become increasingly severe.This paper focuses on a power-converter-based flexible interconnection system for distribution networks and investigates its small-signal stability.Firstly,based on the established small-signal impedance model of the DC side,Million's Theorem is used to obtain the parallel equivalent circuit.Subsequently,the Nyquist criterion is applied to assess stability and determine the corresponding stability boundary.Subsequently,based on a sensitivity analysis of the DC-side impedance transfer function,a quantitative sensitivity index is constructed using the Hco norm.Furthermore,a quantitative index for multi-parameter coupling is established using the Hessian matrix.The coupling effects among control parameters are classified as synergistic and antagonistic,providing a scientific basis for adjusting control parameters.Finally,frequency scanning is performed on the DC-side impedance of the studied system to validate it.Simulations are conducted to verify the stability region,first-order sensitivity coefficients,and multi-parameter coupling results,demonstrating the effectiveness of the proposed analytical method.