Since then it has handled power disturbances on the WPS system flawlessly. Note the marked jump in voltage when the magnet discharges and magnet current drops. During the summer months, the air conditioning demand created by a large influx of tourists to cottages in the scenic north woods further increases the motor load on the system.
Inductive motors pose special stability challenges to utility networks.
Modeling by WPS and American Superconductor showed that, under certain conditions, the network would be unable to recover to nominal voltage following momentary voltage sags from line faults. Ultimately, this could lead to fast voltage collapse, bringing down the entire network. The earliest that line is expected to be in service is 2002, and the company required a customer solution in 2000. Its trailerized configuration also allows D-SMES to be relocated to other sites once a permanent solution is in place. For WPS, D-SMES was the obvious choice.