摘要 |
<p>The improvements consist in using two autotransformers (1-2) connected in parallel to a same phase and provided with respective half-wave rectifiers (5-6) so that the rectifier (5) eliminates the negative half-waves of the autotransformer (1) and the rectifier (6) eliminates the positive half-waves of the autotransformer (2), so that at the input (7) of the tank (8) is obtained an alternating voltage, symmetric or asymmetric according to the needs of each case. Its positive and negative half-waves are indenpendently controllable, through a microprocessor (11) which, according to a program established through a mathematic algorithm and the voltage existing at any time at the input (7) of the tank acts upon automatic regulators (4) of the autotransformer (1-2) and, in this case, upon the thyristors (5-6) which participate in the half-wave rectifiers, in order to control the conduction angles.</p> |