This article provides an overview of the current state of reactive power compensation technologies. The principles of operation, design characteristics and examples of the use of VAR compensators on thyristors and self-commutated converters are given. VAR static generators are used to improve voltage regulation, stability and power factor in AC transmission and distribution systems. Also described are examples obtained from the respective annexes describing the use of reactive power compensators implemented using the new static VAR technologies.

VAR, principles of operation, self-commutated

T. J. Miller, “Reactive power Control in Electric Systems,” John Willey & Sons, 1982.

E. Wanner, R. Mathys, M. Hausler, “Compensation Systems for Industry,” Brown Boveri Review, vol. 70, pp. 30-340, Sept./Oct. 1983.

G. Bonnard, “The Problems Posed by Electrical Power Supply to Industrial Installations,” in Proc. of IEE Part B, vol. 132, pp. 335-340, Nov. 1985.

A. Hammad, B. Roesle, “New Roles for Static VAR Compensators in Transmission Systems,” Brown Boveri Review, vol. 73, pp. 314-320, June 1986.

Nickolai Grudinin and Ilya Roytelman, “Heading Off Emergencies in Large Electric Grids”, IEEE Spectrum, Vol. 34, N° 4, April 1997, pp. 43-47.

Carson W. Taylor, “Improving Grid Behavior”, IEEE Spectrum, Vol. 36, N°6, June 1999, pp. 40-45

Canadian Electrical Association, “Static Compensators for Reactive Power Control,” Context Publications, 1984. [8]. L. Gyugyi, “Reactive Power Generation and Control by Thyristor Circuits,” IEEE Trans. on Industry

Applications, vol. IA-15, nº 5, pp. 521-532, Sept./Oct. 1979.

L. Gyugyi, R. Otto, T. Putman, “Principles and Applications of Static, Thyristor-Controlled Shunt Compensators,” IEEE Trans. on PAS, vol. PAS-97, nº 5, pp. 1935-1945, Oct. 198