The multilevel AC/AC converters have found various applications in high powers and voltages, nominated as the potential third generation of FACTS controllers. These devices have become more popular among researchers, engaging both half-bridge and full-bridge sub-modules. This paper presents a new control and modulation scheme for these converters that provide control of output ac voltage independent of the input ac voltage and the load current as well as input/output reactive power control. Like the advanced UPFC, it is also possible to control the transferred active power between the two sides. Moreover, the dc-link voltages are balanced using the proposed modulation scheme, while a closed-loop control adjust the dc levels at a reference value to secure the stable operation of the AC/AC converter. The whole circuit is simulated with PSCAD and a single-phase laboratory prototype (2kVA, 100V) was implemented, including the power circuits along with the control and modulation blocks to confirm the validity of the proposed schemes.
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