Application and experience with a 15 kV static transfer switch

In an effort to dramatically improve rcliability to a sensitivc customcr, Detroit Edison, a DTE Energy Company, installed a 15 kV Static Transfer Switch (STS). This paper presents the background on the clectrical system disturbanccs which had a ncgative impact on an automotive components plant served by Detroit Edison. Previous steps taken, the studies performed, planning considerations, and the most recent actions taken to resolvc the reliability issues are described. In addition, thc performance of the STS during its first year of service is detailed. This application demonstrates that if there is adequate isolation of thc two sources for thc STS, it can avoid disturbances from voltage sags and outages, thus greatly improving ovcrall reliability for the customcr.