Causality assessment for power quality stationary disturbances

The location of power quality disturbances origin has been widely studied but remains unsolved so far. As disturbances location cannot be established, any evaluation regarding the cause of such disturbances cannot be completely provided either. The Method of Disturbances Interaction - M_DI has proven to provide a solution to quantify the contribution of each circuit connected to a point of common coupling, allowing to identify where disturbances are concentrated. This paper goes further analysing the indicators derived from M_DI in order to identify the causes of stationary power quality disturbances. Causality is evaluated by means of statistical procedures typically employed in epidemiology. Based on the results a novel discussion on responsibilities assignment is presented.