Author : S. Rama Maddileti 1
Date of Publication :7th October 2016
Abstract: In this paper presents a var compensation by a cascaded two-level H-Bridge VSI based multilevel static compensator (STATCOM) using SVPWM. The topology consists of two voltage source inverters are connected in cascaded through a 3-phase transformer. The benefit of this topology is that by maintaining asymmetric voltages at the dc capacitors of the inverters, the levels in the waveform of output voltage can be increases. This results power quality (PQ) improved. The main object of this paper is balancing the dc link capacitor voltages of multilevel inverters during balancing and unbalancing conditions. This controller is controlling inverter voltage in such a way that either –ve sequence current flowing into the inverter is eliminated or reduces the unbalancing in the grid voltages. The performance of the control scheme during balanced and unbalanced conditions is analysed through MATLAB/SOMULINK.
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