Early monitoring results of two voltage sag ride-through devices at a plastics extrusion plant

Voltage sag mitigation techniques command attention in the power quality arena today due to the increasing numbers of sensitive process loads connected to the utility distribution system. This paper presents monitoring results related to the performance of two such devices applied in different levels of voltage sag coverage. The superconducting storage device is designed to protect sensitive loads without the normal segregation of large-power loads (drives, motors) from low-power/high sensitivity machines (computers, programmable logic controllers). The magnetic synthesizer in this case study protects control circuits and requires separation of these circuits from other loads within the sensitive machine. Both methods are effective in reducing process shutdowns due to voltage sags. Their relative economy depends on the type of disturbances affecting the process and the amount of the customer`s economic losses.