| 摘要 |
<p>Device for continuously controlling the amplitude of an essentially sinusoidal alternating electric current (16) flowing in a circuit (15), comprising a control element (17) located in the circuit (15) and means (8) for operating the control element, which electrically exhibits similarly advantageous characteristics as those of known regulating transformers, particularly with respect to low reactive power losses, low noise factors and relatively wide adjusting ranges, but, in contrast to these transformers, allows an almost delay-free continuous electronic control. The control element (17) comprises a parallel circuit of a first and of a second current branch (1, 3) with an inductive resistance (2) in the first current branch (1) and a controllable switching element (4, 5), which can be put into a blocking and into a conducting state, in the second current branch (3), and the means for operating the control element (17) comprise control means (8), in order to put the switching element (4, 5) from the blocking state to the conducting state in each half wave of the alternating current via a variable part of the half wave which can be controlled by the control means (8). <IMAGE></p> |
