The invention discloses an
electric energy quality disturbance
feature extraction method and
system based on segmented multi-resolution S transformation, relates to the technical field of
electric energy quality monitoring, and aims to solve the problem that
electric energy quality disturbance features of different frequency bands are difficult to accurately capture due to fixed resolution in a traditional time-
frequency analysis method. The method comprises the following steps: establishing mathematical models of
power quality disturbance signals, wherein the mathematical models comprise multiple single and composite disturbance models; discretizing the
signal based on continuous S-transform and applying one-dimensional discrete S-transform; dividing a
frequency band into a low section, a middle section and a high section according to disturbance frequency characteristics;
gaussian window functions containing different adjustment factors are respectively introduced into each
frequency band so as to adaptively adjust the time-
frequency resolution; combining S transformation with the
window function to obtain a discrete expression of segmented multi-resolution S transformation; and extracting disturbance characteristic parameters based on the transformed time-
frequency matrix. According to the technical scheme, self-
adaptive optimization of the time-
frequency resolution is realized, and the extraction precision and reliability of complex
power quality disturbance characteristics are improved.