A REVIEW DEVELOPMENT OF MODELING, SIMULATION AND CONTROL OF THE ALTERNATE ARM CONVERTER

Abstract

The The High-voltage direct-current (HVDC) technology enables efficient, long-distance electric-power transmission renewable-energy integration. Converter topology determines the overall performance of such systems. Conventional two-level voltage-source converters (VSCs) offer high dynamic response but suffer from lar switching losses and insufficient fault protection. Modular Multilevel Converters (MMCs) overcome these limitations through a scalable structure but demand substantial capacitor energy storage.The Alternate Arm Converter (AAC) has emerged as an attractive hybrid topology combining the favorable features of both systems: reduced conduction losses, lower energy storage, and inherent DC-fault block capability. This thesis presents comprehensive modeling, control design, and performance evaluation of a three-phase AAC. Analytical expressions of arm currents, capacitor voltages, and circulating currents are derived. A hierarchical control architecture outer DCvoltage loop, inner dq-current loop, circulating-current supply and submodule-balancing mechanism is implemented in MATLAB/Simulink. Simulation results confirm theoretical predictions