Narain G. Hingorani

Flexible AC transmission

The operation and components of the flexible AC transmission system (FACTS) are described. FACTS, designed to overcome the limitations of the present mechanically controlled AC power transmission systems, uses reliable, high-speed power electronic controllers. Its benefits are examined. These include greater control of power, so that it flows on the prescribed transmission routes; secure loading of transmission lines to levels nearer their thermal limits; greater ability to transfer power between controlled areas, so that the generation reserve margin may be reduced; prevention of cascading outages by limiting the effects of faults and equipment failure; and damping of power system oscillations.<<ETX>>

Power electronics in electric utilities: role of power electronics in future power systems

The role of power electronics in future power systems is considered. The improvement of power semiconductors is held up as a major factor to the increased importance of this role. Power electronics applications for HVDC transmission are discussed. >

High Power Electronics and flexible AC Transmission System

During the last decade, higher energy costs, the difficulty in building new power plants and improved converter technology provided an increased Market for HVDC transmission. However, HVDC, due to the high cost of converters, will play a limited role in the overall ac power system. The author discusses the potential of thyristors in ac power systems. The concept of a thyristor-assisted ac power system, called Flexible AC Transmission System is introduced and discussed.

A New Scheie for Subsynchronous Resonance Damping of Torsional Oscillations and Transient Torque - Part I

Series capacitor compensation of long and medium lines offers convincing advantages of optimum use of transmission lines. Technical problems with series capacitor protection and, more recently, the problems of subsynchronous resonance, resulting in high stresses on the turbogenerator shafts, have been a deterrent to widespread use of series compensation. Some generally complementary solutions to these problems have emerged, but further advances are needed.

HVDC Circuit Breaker Development and Field Tests

With the growth of direct current transmission, the need and scope of application for a high voltage direct current circuit breaker have increased. This paper reports on the development of two different dc breaker prototypes and full scale field tests of these breakers on the ±400-kV, 1360-km long Pacific DC Intertie.

Future Opportunities for Electric Power Systems

From time to time innovations and breakthroughs have caused major changes and improvements in electric power systems. These changes and improvements ultimately result in benefits to the consumer of the lower cost electricity and high reliability. Past examples of these innovations include the transformer, induction motor, synchronous generator, mercury arc valve, and others. More recently, these innova¬ tions and break-throughs include SF6 insulation, polymer in¬ sulation, transistor, thyristor, metal oxide arrester and oth¬

A New DC Breaker Used as Metallic Return Transfer Breaker

When a bipolar HVDC transmission system is operating monopolar using the earth as a return path, it is often desired to divert the return current from the earth to the line frot the unused pole. To do so requires either that the system be shut down temporarily or that a dc circuit breaker be used. This paper describes the development of such a new dc circuit breaker, and its application on the Pacific Intertie as a Metallic Return Transfer Breaker (MRTB).

Design, Development and Testing of 1200 kV and 550 kV Gapless Surge Arresters

This paper outlines the objectives of the EPRI development program on the 1200 kV and 550 kV gapless metal oxide arresters. Six important design considerations are described along with the verification testing involved with each. Final test results are presented on the individual arrester units as well as the complete 1200 kV and 550 kV poles.

Research coordination for power semiconductor technology

The National Power Semiconductor Interagency/Utility Consortium has been formed to coordinate US research activities for development of materials and technologies related to high-power semiconductors. The history, activities, and investment strategy of this consortium are described briefly. The most promising power electronics devices considered by the consortium are discussed, leading to the conclusion that field-effect transistors and metal-oxide semiconductor (MOS) controlled thyristors (MCTs) will eventually dominate power-switching applications. New packaging techniques are also presented, in which silicon is used to replace bulky ceramic insulators and copper contacts, an arrangement that promises to lower costs and weight while improving device performance and life. Finally, the authors review policy issues related to power semiconductor research and recommend that R&D in this field be treated as a leading national priority. >

Survey of Creepage Distances and Clearances in HVDC Converter Stations

In comparison with the long term experience on clearances and creepage distances of power frequency voltages, experiences with direct current voltage have been relatively short and limited. This paper which is sponsored by the IEEE Working Group 79.5 Clearances and Creepage Distances in HVdc Converter Stations, describes the result of a survey among various electrical utilities around the world based on their design and/or operating experience of high voltage direct current (HVdc) converter stations. It is intended as a practical reference and guideline to be used by electrical utility engineers, operating and maintenance personnel, as well as HVdc equipment manufacturers. The survey includes environmental conditions, creepage distances, clearances, maintenance and operating experience for each converter station, followed by an analysis for each category.