Application of Prony analysis to the determination of modal content and equivalent models for measured power system response

It has been shown by J.F. Hauer et al. (ibid., vol.5, p.80-90, Feb. 1990) that Prony analysis can be very effective in response-based modal analysis of noise-free linear time-invariant (LTI) systems. This methodology extends Fourier analysis by directly estimating the frequency, damping, strength, and relative phase of the modal components present in a recorded signal. This earlier work is extended, concentrating upon power system planning applications, for stability program outputs. Results are presented for modal analysis and detailed model construction based on response data obtained through large-scale tests of the western US power system. An optimal modeling program, SYSFIT, is used to supplement the measurements