INTRODUCTION

Synchrophasor measurements have gradually gained acceptance since their invention in the 1980s.  Major blackouts have given great emphasis to this technique due to the need for better disturbance analysis and more situational awareness.  The main application for these measurements is disturbance analysis, and it is a well established practice in the WECC.  Displays for situational awareness are quickly moving into practice, but are still not considered "essential".  State estimation with phasor data is also moving into common use.  Controls have been prototyped and demonstrated with success.  

The Salazars were just sitting down to dinner when the lights flickered, dimmed slightly, and then steadied to normal in a few seconds.  Six-year old Ramon said "I'll bet the 'lectricity gremlins just got another wire!"  Little did they realize lightning had caused a flashover that in turn caused a breaker failure at a 500 MW power plant.  The plant tripped off line, and the loss in power was made up by generation up to 900 miles away.

Such is the nature of the huge modern power grids that span continents.  Due to the size and distribution of current power grids, most power consumers have little idea of where their power comes from or what it takes to get it there.  For that matter, many workers in the power industry have little idea either.  Connecting and operating grids distributed over large geographic areas is a complex and exacting job.  Grid growth is primarily driven by economics, but also serves reliability and environmental needs.  However growth has increased operational problems.  Unexpected system oscillations, line overloads, and generation deficiencies have increased with demand and the need for greater system utilization.  These small events have been underscored by large scale problems such as the blackouts in 1996 and 2003.  All these problems have shown the need for better modeling of the dynamic power grid, better operational planning, more system controls, and increased operational grid awareness.  A Wide Area Measurement System (WAMS) can significantly aid in implementing some of these needs.