Variable transformer with an electronic controller

摘要

The invention relates to a variable transformer having a primary winding (fixed winding) which is arranged around one or more transformer cores and, magnetically coupled thereto, secondary windings (variable windings), and having an electronic controller in order to achieve a secondary voltage which is at least approximately continuously variable. In order to achieve voltage regulation in such fine steps that a step width of 1% is not exceeded, the secondary windings (3) are constructed as winding groups (3a to 3e), which are electrically isolated from one another, with numbers of turns in the ratio of an increasing infinite numerical sequence. The individual voltages induced in the individual winding groups (3a to 3e) can in each case be connected together either in the same sense or in with respect to senses so that any desired voltage from the voltage value zero to the voltage limiting value can be set by connecting all the winding groups (3a to 3e) one behind the other, with the voltage of the winding group (3a) having the smallest number of turns as the voltage interval. <IMAGE>