Before the QuadBooster transformers can be put into operation, the on-load tap-changers must be set by MR specialists. The special arrangement of the transformer windings requires this particular adjustment work. It is the only way to ensure correct operation. Two MR experts traveled to the Kemsley transformer station during July, 2011.
Two of the 2750 MVA QuadBooster transformers which are designed for a voltage of 400 kA are in use at Kemsley southeast of London. The third unit will be installed north of Manchester. These QuadBoosters are special phase-shifter transformers. QuadBoosters are made up of one shunt and one series unit. Each shunt unit contains six OILTAP® R I 3003-123/E-18 35 1WS’s. TAPGUARD® 260’s monitor all relevant parameters of the on-load tap-changers.
Since the QuadBooster transformers have very high capacities, an extraordinarily strong potential connection occurs. This extreme potential connection places special demands on the on-load tap-changers. The change-over selectors of the two on-load tap-changers each of which is used during one phase must move synchronously. MR uses a very special measuring setup which was developed especially for this purpose to check the synchronicity.