Railway Power Supply System using Modular Multilevel Converter with Droop Characteristics

Indian railway locomotives are fed through singlephase transformers connected to two adjoining phases, this network leads to power quality issues such as voltage distortion, negative sequence currents, high reactive power drawn from the utility grid and harmonics to the three phase grid supply, in addition to that neutral sections (NS) which are present in phase splitting or co-phase supply system causes the speed reduction in locomotives. In this paper three phase grid supply to single phase catenary power transmission system for high speed railway is adopted by using Modular Multilevel Converter (MMC). In order to eliminate neutral sections and to reduce the power quality problems MMC based traction substation (SS) is modelled. MMC centered traction substation and droop characteristics of single phase inverters of two adjacent traction substation is studied and analyzed using MATLAB/ Simulink
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