TY - EJOUR
AU - Chaudhari, Himanshu N
AU - Darji, Pranav B
PY - 2024
DA - February
TI - Asymmetrical Modular Multilevel Converter (A-MMC) with Mixed Cell Sub-Modules (SM) for Improved DC Fault Blocking Capability and Reduced Component Count
T2 - Majlesi Journal of Electrical Engineering
VL - 17
L1 - https://oiccpress.com/Majlesi-Journal-of-Electrical-Engineering/article/asymmetrical-modular-multilevel-converter-a-mmc-with-mixed-cell-sub-modules-sm-for-improved-dc-fault-blocking-capability-and-reduced-component-count/
DO - 10.30486/mjee.2023.1970275.0
N2 - In this article, asymmetrical modular multilevel converter (A-MMC) topology using mixed cell (SM) with DC-side fault blocking capability and the reduced component count is proposed. The mixed cell submodule is made up of a full-bridge (FB-SM) and a half-bridge (HB-SM) with asymmetric capacitor voltage based on geometric propagation (GP) ratio. Each mixed cell submodule can generate a maximum of four output voltage levels with binary GP ratio and five output voltage levels with ternary GP ratio using six controlled switches and two asymmetric capacitors. The proposed A-MMC topology requires nearly half the number of components and voltage sensors compared to conventional topologies. This will result in simpler control structure of A-MMC with DC fault blocking capability. A voltage balancing algorithm based on normalization is used for capacitor voltage balancing and a hybrid pulse width modulation (H-PWM) technique to generate gating signals. Detailed operational concepts of the proposed topology, the pre-charging process of a capacitor, and performance with different modulation indexes are discussed in length. A detailed simulation model of A-MMC under different operating conditions is carried out using MATLAB/SIMULINK environment. To show the benefits of mixed cell SM, a comparison between the proposed mixed cell and other existing cells is presented in detail. The simulation results analysis show effectiveness of proposed schemes over other schemes presented in literature.
IS - 1
PB - OICC Press
KW - Asymmetrical Modular Multilevel Converter (A-MMC), HVDC system, Mixed Cell, Hybrid modulation technique, Reduced Component Count. DC Fault Blocking Capability 
EN -