Progress in Extra-High-Voltage Power Transmission

In Part I of this paper a review is presented of the present status of extrahigh-voltage (EHV) power transmission (275 kv and higher) in this country and abroad. A forecast is made of the future requirements and developments of EHV transmission in the United States for the next 20 years, to 1977. It is concluded that: 1. there will be continued and rapid expansion of EHV systems at the highest voltage presently used, 345 kv; 2. that a higher voltage of the order of 460 kv will be introduced probably about 1962 in this country, and 3. a still higher voltage of the order of 650 kv may possibly be introduced about 1975. In Part II the problems are reviewed which must be solved by the utilities and manufacturers in this country in order to transmit power at these higher voltages reliably and economically. Areas of technical work are identified and the problems of EHIV technology are classified accordingly. The means which are available for the solution of these problems are then reviewed: analytical work, laboratory investigations, experimental lines, prototype EHV systems, and, of course, tests on the actual systems. It is concluded that all these means are necessary to obtain a proved solution. There is no doubt that the American electrical industry will continue to meet successfully the challenges presented by the ever-increasing requirements for electric power at a reasonable cost.