Improvement of Transmission Capacity by Thyristor Controlled Reactive Power

This paper shows that thyristor controlled reactive power can be used as an efficient tool to improve damping of large power systems. If thyristor switched capacitors are used there will also be positive contribution to transient stability. Examples of power systems where damping is the critical factor have been investigated. The use of supplementary control of generators and control of reactive power has been studied. Basic configurations of thyristor switched capacitors and thyristor controlled reactors are presented.