Considering the wide frequency range, strong nonlinearity, and multimodal characteristics of "double high" power systems, an adaptive identification method for broadband oscillation modes was proposed. Firstly, an adaptive threshold filtering technique was applied to the spectrum of the Blackman-Harris windowed signal to extract the dominant components. Then the three-spectrum line interpolation FFT and the ZoomFFT were used to adaptively analyze the signals after using main-lobe interference criterion of modes with close frequencies. Finally, the proposed method was tested by using 20-mode example signals and a measurement signal of a power system model. The results demonstrate that the method can accurately identify the parameters of complex broadband oscillation modes, adapt to various oscillation scenarios, and meet the signal characteristics of "double high" power systems, thus confirming its applicability and feasibility.

broadband oscillation  /  main-lobe interference  /  windowed interpolation FFT  /  ZoomFFT