Identifying torsional modal parameters of large turbine generators based on the supplementary-excitation-signal-injection test.

Highlights: [•] The new approach is based on the supplementary-excitation-signal-injection test. [•] It can identify frequencies and mechanic damping of all torsional modes concerned. [•] A solid theoretical foundation is established upon the dynamic shaft model. [•] A systematic test and identification procedure is developed. [•] The approach is applied in practical systems and validated through field test. [ABSTRACT FROM AUTHOR]