Synthesis of sensitivity coefficients for controller parameters of static VAr compensator

Traditionally, a lead/lag circuit is regarded as providing phase compensation for a controller, so a few lead/lag stages would be needed to achieve sufficient phase shifts at the frequency of concern. A different viewpoint is offered as a basis of the SVC damping controller design. From time constant synthesis, three different objectives of a properly designed lead/lag circuit are highlighted, but the dominant one is associated with gain compensation, rather than phase compensation. Moreover, the required number of stages, the choice of lead or lag compensation, and the selection of the time setting ranges are all indicated from the synthesis.