Simulation-based Analysis of a Dynamic Voltage Restorer under Different Voltage Sags with the Utilization of a PI Controller

摘要

Power quality problems are becoming a major issue.Every utility company consumer desires to receive steady-statevoltage, i.e. a sinusoidal waveform of constant frequency asgenerated at power stations, but the influence of disturbances inthe shape of sags and swells, interruptions, transients andharmonic distortions which affect power quality, resulting in lossof data, damaged equipment, and augmented cost. The mostpowerful voltage disturbance is the sag voltage. In this paper, aDynamic Voltage Restorer (DVR) is proposed for sag voltagecompensation. It is cost-effective and protects critical loads in agood manner from balanced or unbalanced sag voltage. Controlstrategy (such as a PI controller) is adopted with DVR topologyand the performance of such a device with the proposedcontroller is analyzed through simulation in MATLAB/Simulink.Three types of faults are utilized, which are available inMATLAB/Simulink pack, for obtaining the sag voltage. Thespecific range of total harmonic distortion percentage is alsodiscussed. After the result validation of the DVR topology inMATLAB/Simulink, it has been seen that the proposed topologyis able to compensate the sag voltage of any type of fault andreduce the unbalancing and voltage distortions of the grid.