Electric Power Systems

Electric power lines are interconnected throughout broad areas of the United States to share loads during special times, such as differing peak-power periods or local hot weather, high energy-demand occasions. The magnetic storm field variations induce undesirable currents to flow in these long conducting transmission lines (Figure 2.25). In general, the nearer to the region of auroras, the greater the induced fields. At high-latitude locations, such as northern Europe, Canada, and the northern United States, during major magnetic storms, the induced magnetic fields have damaged expensive transformers of the interconnected power systems, causing extensive electric power failures

Conductivity (ohm-meter)'1

FIGURE 2.24 ► The Earth's electrical conductivity increases rapidly with depth. Using this conductivity information together with seismic records, laboratory testing, and a knowledge of the fundamental properties of matter, geophysicists have learned the structure and composition of the Earth's regions that are completely inaccessible in any other way.

Conductivity (ohm-meter)'1

FIGURE 2.24 ► The Earth's electrical conductivity increases rapidly with depth. Using this conductivity information together with seismic records, laboratory testing, and a knowledge of the fundamental properties of matter, geophysicists have learned the structure and composition of the Earth's regions that are completely inaccessible in any other way.

at great inconvenience and expense to the public. An intense magnetic storm in 1989 was responsible for a 9-hour electric blackout throughout Québec Province, Canada, and extensive power grid damage that spread through the northeastern Unitd States. Six million people were affected by that power outage.

0 0

Post a comment