Clapham static VAr compensator control retrofit

The performance of the Clapham SVC after a control retrofit is described. The replacement of an analogue with digital control was completed in 1995. The retrofit was accomplished well within the ten days of allotted shut down time. With the original control system ac system voltage unbalance caused by untransposed lines had to be balanced by manual adjustment. The primary improvement provided with the new control is automatic and continuous voltage balancing.