A High-Precision Measurement Method for Quasi-Peak of 9-150 kHz Disturbances

The IEC SC77A/WG9 is currently working toward the definition of a normative method for measuring disturbances from 9 to 150 kHz in power grids. In this paper, we propose a new digital implementation of the super-heterodyne receiver. In this method, the 9–150 kHz disturbances are first pre–detected with low computational cost, and then the pre–detection results are converted into adaptive filter parameters, which greatly reduces the initial tracking time of the adaptive filter. In the simulation of steady state signals and step signals, the proposed method can limit the initial value of frequency tracking within 2 kHz at the beginning of detection, which significantly shortens the tracking process.