I.V. Volkov, A.I. Chyzhenko
ABSTRACT
The article deals with the problem of power supply by the network of controlled diode rectifiers commensurable with the network of rectifier power. In such a system there is a distortion of the mains voltage, as a consequence of controlled diodes (thyristors) commutation processes leading to formation of so-called switching platforms known as «notches».A method and corresponding design are proposed, that permits to avoid the factors distorting the mains voltage. This is achieved through the use of voltage boost low-power pulse transformers which generate special pulses into mains that compensate the notches and surges of voltage. Such pulses are generated exclusively in the moments of thyristor switching and their duration is proportional to the angle of thyristor commutation. To implement this method 3 single-phase voltage boost pulse transformers are used, the secondary windings of which are incorporated directly into the network phase wires (up to rectifier input). The primary windings through a voltage divider and auxiliary diodes forming corrective pulses are connected to the rectified voltage (at the output of the rectifier). Formation of the corrective pulses by auxiliary thyristors is carried out in accordance with a specially developed algorithm of control described in the present work. Since the power of pulse transformers is completely determined by the power of switching platforms and does not exceed
it, such a circuit design differs favorably from alternative devices that usually use powerful components, permanently connected to mains.
KEYWORDS
correction of the form voltage, rectifier, switching platforms.
REFERENCES
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