Feature Analysis for Exhaust Gas Temperature of Turbo Shaft Engine Based on Hilbert-Huang Transform

A new procedure based on Hilbert-Huang Transform (HHT) was proposed to investigate the change of the exhaust gas temperature (EGT) of turbo shaft engine. Energy-frequency-time distribution of the signal can be established though empirical mode decomposition (EMD) and Hilbert transform, from which Hilbert energy spectrum was obtained. The energy spectrum was applied to indicate the energy distribution of the signal on the frequency axis. The variation of EGT changing with time was researched by using instantaneous energy. At the same time, the signals of EGT were decomposed into intrinsic mode function, by which can eliminate the effect of noise on original signal. Feasibility of the method had already been verified by the tests.