Design of a robust fixed-parameter SVC damping controller through graphical loop-shaping technique

A novel robust damping controller for a static var compensator (SVC) has been designed using a simple graphical technique. In the robust design, the variations in operations from a nominal condition are modeled as multiplicative unstructured uncertainty. A loop-shaping technique is employed to solve the robust stability and performance constraints in H-_∞ space graphically. The robust constant parameter controller designed has been tested for a range of operating conditions considering a number of disturbances on the system. It is observed that the robust controller provides extremely good damping for a good range of operation. The electrical transients as reflected in the system voltage variations are also extremely good.