Voltage Sag Study for a Practical Industrial Distribution Network

Voltage sags have become one of the major power quality concerns in recent years. To decide the suitability of mitigation methods, knowledge is needed about the expected number of sags as a function of special characteristics; this knowledge can be obtained through voltage sag analysis software, which is developed in the paper based on the method of fault position. The software has many functions; a detailed voltage sag study for a practical industrial distribution network by using it has been done in this paper. In order to assess the degree of fault position influence on voltage sags of the power system, an index named fault position sag coefficient (FPSC) is defined in the paper. This coefficient can be calculated out based on the results of voltage sag analysis software. The dangerous fault positions which cause serious voltage sags can be determined.