What is transformer tap changer?

A tap changer is a device used to change the primary or secondary voltage of the transformer by changing the turn’s ratio without remodeling the transformer. The primary function of the transformer is it removes or connects some portion of the winding either load side or source side. The importance of tap changer is maintaining the load side voltage constant irrespective of load variations. There are two types of tap changer one is off-load changer and on-load tap changer.