CUSTOM POWER DEVICES FOR VOLTAGE SAGS MITIGATION: A TECHNO-ECONOMIC ANALYSIS

Abstract

The increased concern about the financial losses due to voltage sags and interruptions plus the advancements in power electronics technology have led to the innovation of very fast acting intervening equipment that can mitigate such disturbances at the facility entrance. Although significant improvements in the overall power quality can be achieved, however, the high cost of these custom power devices can offset the benefits resulting from their application. The problem therefore, is one of finding a compromised solution that makes technical and financial sense. In this paper, the technical merits of the custom power devices are highlighted, along with their effectiveness in mitigating sags and/or interruptions. The costs of each application are financially analyzed together with a procedure for the decision maker to compare the payback or the revenue of investment in such devices. A case study of an oil refinery in Alexandria, Egypt is considered to validate the proposed procedure. The results showed that the best solution would be the use of a Static Transfer Switch (STS) provided with two feeders electrically separated. Otherwise, the Dynamic Voltage Restorer (DVR) will be the best solution.