HVDC controls for system dynamic performance

The controllability of HVDC links is often cited as an important advantage of DC systems. This controllability can be valuable in improving the dynamic performance of large power systems. To achieve the promised advantages, control systems must perform appropriately for various disturbances and system conditions. The controls, which can be quite powerful, must not interact unfavorably with other high-performance controls. The application of special (or supplementary) HVDC controls for power system dynamic performance improvement is addressed. The topics addressed are reactive power regulation, dynamic AC voltage support, damping of frequency oscillations and augmenting transient stability, special controls during faults, operating experience, and future trends