In this study, a new topology for dynamic voltage restorer (DVR) has been proposed. The topology is inspired by the buck-boost ac/ac converter to produce the required compensation voltage. This topology is able to compensate different voltage disturbances such as sag, swell and flicker without leap of the phase angle. The mass of the proposed topology has been reduced due to lack of injection topology. In addition to, the required compensation energy is directly delivered from the grid through the grid voltage. Therefore, the massive dc-link capacitors are not required to implement. To verify the qualification of the topology, the simulation results by MATLAB/SIMULINK software have been presented. Moreover, an experimental prototype of the case study has been designed and tested.
Fig. 1 Proposed topology
EXPECTED SIMULATION RESULTS:
Fig. 2. Simulation results for sag compensation
Fig. 3 Simulation results for swell compensation
Fig. 4. Simulation results
In this paper a new topology for DVR using buck-boost ac/ac converter was proposed. This topology contains five bidirectional switches, an inductor and a capacitor. Unlike the conventional topologies, the proposed DVR does not have any injection transformer due to the structural features. Because of direct connection to the grid, the storage elements are not required in the proposed topology. Therefore, this topology has less physical volume, mass and price in comparison with traditional topologies. Any kind of voltage disturbances can be compensated by the proposed topology and the effective operation has been confirmed by simulation and experimental results.
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