Power rectifier for direct current link

Review of modern power systems shows that along with the AC lines, a number of the world-leading countries use high-voltage DC link as a connection between the energy systems. DC power inserts can reach 8 GW (China), which causes, in some cases, a higher return on electricity transmission. The core of DC transmission lines is the thyristor rectifier, the quality of which depends on the number of phases of the rectified voltage and the amount of output ripple. The main circuit in the case of high-voltage inserts is a permanent 12-pulse rectification circuit with a series connection of three-phase Rectifier Bridge. It provides an optimal balance of quality and output voltage, and power supply for one of the rectifier bridge is implemented with a secondary winding in a triangle that requires an increased number of turns and a corresponding increase in weight and the dimensions of the supply transformer. The proposed version of the article provides a twelve-rectifier output voltage ripple using the same inclusion of both secondary windings' star. This provides considerable savings of active transformer materials and improves the ergonomics while reducing costs. Due to lower inductance of the secondary winding phase switched, such a solution has a better electromagnetic compatibility.