Modal Frequency Sensitivity for Power System Harmonic Resonance Analysis

Resonance-mode analysis is effective to determine the contributions of different network components to a resonance in power system harmonic studies. There are two forms of modal sensitivity in harmonic resonance mode analysis, that is, the modal impedance sensitivity and the modal frequency sensitivity. This paper presents a method to compute the modal frequency sensitivity index. The analysis results are compared with those obtained by using the modal impedance sensitivity index to clarify the differences and similarities between the two sensitivity indices. The comparison shows that these indices complement each other and should be used to jointly diagnose power system harmonic resonance problems.