A composite power quality indication generated from user weighted statistical
contributions
of selected system parameters provides an overall indication of power quality in
an electric power distribution system. The user defined weightings are maintained
over time by continually updating sensitivities that normalize the component contributions
to the composite power quality indication. The current composite power quality
indication is displayed in relation to its long-term mean and to dynamic thresholds
determined as multiples of the standard deviation of the long-term mean.