Two yoke instrument transformer with control circuit - has two parallel controlled magnetic circuits in each yoke

摘要

The tap changing instrument transformer has one of its coils provided with a controllable winding part. At least one yoke (3) contains several parallel, controlled magnetic circuits, forming an additional transformer window (10), housing the controllable winding part (9). Each of the magnetic circuits carries premagnetising coils (11, 12), connected to the control circuit and affording magnetic commutation of the controllable winding part. The parallel magnetic circuits are preformed by closed magnetic conductor loops (5,6) in the yokes, which carry premagnetising coils (11, 12) under direct current.