CASE STUDY

The following article describes key technology areas that have been identified to modernize the transmission and distribution of electric power.

Included in this article are discussions of the following:

(1) advanced control features including flexible ac transmission systems (FACTS);

(2) advanced protection including digital technology for relays, communication and operation;

(3) synchronized phasor measurement units (PMUs) achieved through a Global Positioning System (GPS);

(4) automatic calibration of instrument transformers using PMUs;

(5) precise state measurements and estimates; and (6) intelligent visualization techniques.

CASE STUDY QUESTIONS

A. What is a flexible ac transmission systems (FACTS) device? One example of a FACTS device is a static synchronous compensator (''STATCON'').

Briefly describe what a STATCOM is and find the location of one STATCOM device currently that has been installed in the United States (use the Internet).

B. What is a phasor measurement unit (PMU) in electric power systems? What is a synchronized PMU? What is measurement system called that incorporates PMUs deployed over a large portion of a power system?

C. How could a PMU be used to improve the performance of an instrument transformer?