UPFC Installation
At American Electric Power Is Operational

INEZ, Ky., May 1, 1998 -- It´s official. The world´s first Unified Power Flow Controller (UPFC) -- an advanced solid-state transmission system control technology -- is up and running at American Electric Power´s (NYSE: AEP) Inez Station in eastern Kentucky.

Developed by AEP, the Electric Power Research Institute (EPRI) and Westinghouse Electric, the UPFC, which went into test operation April 22, will improve the reliability and quality of bulk power transfers, and allow utilities to control the flow of electricity through a transmission network. EPRI believes the UPFC is one of the most significant technological advances in the history of this industry.

According to Bruce Renz, AEP´s vice president for Energy Delivery Support, the UPFC was constructed in two Phases and will undergo a battery of performance tests over the next several weeks. Phase I, which consisted of a +160MVAR shunt inverter for voltage support, is connected to AEP´s existing 138-kV station. Phase II, a +160MVAR series inverter for power flow control, is connected to a new very high capacity 138-kV transmission line which was built last year.

"This unique UPFC-enhanced transmission line, combined with the rebuild of older transmission lines in southwestern West Virginia and eastern Kentucky, will significantly increase the transfer of reliable power into Martin and Pike counties in Kentucky," Renz said.

"Inez is a major coal mining area, and electricity sales have steadily increased over the years. The UPFC will be a great benefit because it will help us maximize use of our lines. It will enable control of power flow into and out of the area, effectively maintain voltage throughout the area, and improve stability."

Normally, control of power flow through the transmission network is very difficult because mechanical devices are too slow to switch alternating current cycle by cycle. As a result, power flows in the direction it "wants" to flow -- along parallel paths of least resistance. What´s more, existing equipment, such as capacitors, reactors or synchronous condensers can provide only so much voltage support, and lack the rapid smooth control of a UPFC. The UPFC can redirect power flow on existing lines to utilize more of the overall system. They can also react almost instantaneously to counteract disturbances on a transmission line, improving system stability.

"It is extremely satisfying to see concepts we imagined a decade ago become reality as a result of AEP´s technological leadership," Renz said.

EPRI, established in 1973 and headquartered in Palo Alto, Calif., manages science and technology programs for the energy and energy services industry worldwide.

Westinghouse Electric Corporation, a diversified, multi-industry company headquartered in Pittsburgh, Pa., is a world leader in developing energy management power electronics technology. Westinghouse Power Generation, a market and technology leader in the global energy supply business, is headquartered in Orlando, Fla.

AEP, a global energy company, is one of the United States´ largest investor-owned utilities, providing energy to 3 million customers in Indiana, Kentucky, Michigan, Ohio, Tennessee, Virginia and West Virginia. AEP has holdings in the United States, the United Kingdom, China and Australia. Wholly owned subsidiaries provide power engineering, energy consulting and energy management services around the world. The company is based in Columbus, Ohio. On Dec. 22, 1997, AEP announced a definitive merger agreement for a tax-free, stock-for-stock transaction with Central and South West Corp., a public utility holding company based in Dallas.

For more information, contact:

Lenore Leadingham
Ky. Corporate Communications Manager
(606) 327-1230

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