Nowadays in high-power industrial processes, multipulse cycloconverters are the most commonly used converter for high power mill drives. This paper propose an analysis of the interharmonics currents behavior under an unbalanced load, injected by a Cycloconverters (CCVs) with 12-pulse configuration and multi-winding transformers. Three-phase transformers with two secondary windings with star and delta connection and a three-phase RL load with a decoupled direct current load control are used to simulate the system. The prototype of the power system is embedded on a real-time simulator. Performance is tested on a digital real-time power system simulation (RTDS) and results are analyzed with external equipment and compared with theory.