Economic loss assessment of voltage sags

As one of the major problems of modern power quality, voltage sag will bring huge economic losses. From the economic point of view, assessment of voltage sags is discussed in the paper, on the basis of analyzing the main factors of voltage sag causing economic losses. According to the composition ratio and changes in voltage tolerance range of sensitive equipments, voltage tolerance curve (VTC) of integrated load-sensitive can be obtained. On this basis, the equipment failure probability matrix (P), voltage sag frequency matrix (F) and economic loss matrix (E) are defined, with the remaining voltage and the sag duration as variables. In addition, the quality loss function is introduced to evaluate the economic losses of various types of voltage sags, thereby establishing the economic loss assessment method of voltage sags. By knowing from the analysis, the method is convenient, fast and accurate, which can assess the economic losses of voltage sag effectively.