Current sharing control circuit of 12 pulse rectifier

摘要

The present invention is a three-phase thyristor rectifier for rectifying the three-phase power supply of the R, S, and T phases to supply a DC power supply to the load, and in particular, when three thyristor 6-pulse phase rectifiers are used to supply power to the load, two three-phase The present invention relates to a current sharing control circuit of a 12-pulse rectifier in which the same load is shared with the Lister rectifier.;Conventionally, since one rectifier control signal is controlled by moving as much as the phase displacement generated in the power circuit, load sharing is not precisely performed according to the product and circuit characteristics, and two rectifier currents are detected to change the control amount of the corresponding rectifier. Therefore, it is accurate only at the initial setting load, current deviation occurs at other loads, and DC voltage decreases with increasing load.;In order to solve the above problems, the present invention, when supplying a DC power supply to the load with two three-phase thyristor rectifier receives the output DC voltage and each rectifier detection current to generate the respective rectifier control amount to control the thyristor through the corresponding drive unit By changing the angle, the output voltage of each rectifier is controlled constantly and the load sharing is made equal.