  The paper presents an innovative approach to identifying voltage fluctuation
sources in power networks, also considering the localization understood as the
indication of supply points of disturbing loads. The presented approach
considers disturbance sources that change their operating state with a
frequency higher than the power frequency. The implementation of the proposed
solution is also proposed in such a way that its implementation in the smart
meter infrastructure allows automatic localization of disturbance sources
without additional expert knowledge. In the proposed approach, the modulation
signal is estimated using a carrier signal estimator, which allows the
estimation of a modulation signal with a frequency higher than the power
frequency. The estimated modulating signal is decomposed into component signals
associated with individual disturbing loads by decomposition by approximation
using pulse waves. The decomposition process allows for the estimation of
selected parameters associated with disturbing loads, on the basis of which the
assessment of propagation of voltage fluctuations associated with the impact of
individual disturbance sources is performed, which allows for the indication of
their supply point. The proposed approach was verified in numerical simulation
studies using MATLAB/SIMULINK and in experimental studies carried out in a real
low-voltage power grid.
