Motivation and Issues of Interest
Research in PQ has traditionally been motivated by the need to supply distortion- and disturbance-free voltages to the end-user loads [1], [2] so that these loads operate properly. Voltage and current disturbances in the power system are a normal part of system operation, but these disturbances can cause incorrect operation of customer equipment. Characterizing these incompatibilities requires an understanding of the disturbances themselves and their possible impact on customer equipment. Devices to measure and characterize the disturbances (PQ monitors) have been widely used and have helped create new research opportunities that use the measured voltages and currents to indicate possible equipment and system problems (referred to as equipment diagnostics).