ENHANCING POWER QUALITY WITH HREE-LEVEL INVERTERS IN DYNAMIC VOLTAGE RESTORERS

Abstract

Customer pollution is the most important element influencing distribution network power
quality (PQ). The sensitive loads must be safeguarded from swells, sags, source voltage imbalances, and so
on. The answer is a dynamic voltage restorer (DVR). Dynamic voltage restorers are series-connected
compensators. When the voltage varies, a DVR must power the load. Multiple DVR inverters improve the
harmonic performance of the system. Synchronous reference frame control is used for DVR control. The
design and simulations of a three-level inverter-based DVR are described in this work. In MATLAB,
simulate and analyze a three-level and two-level inverter DVR. The results reveal that a three-level inverter
raises load voltage THD while injecting a series voltage keeps the reference value constant.