Application of DVR based Trinary Hybrid Multilevel Inverter to Improve Power Quality of Sensitive Loads

In this paper, a new dynamic voltage restorer (DVR) based on a Trinary Hybrid Multilevel Inverter (THMI) is proposed, which is capable of compensating for voltage sag, swell and flickers for sensitive loads. A Trinary Hybrid nine-level inverter is composed of a smaller number of IGBTs and circuitry compared to similar structures. The base structure of this inverter is based on the connection of the H bridges and consists of two inverters of a single-phase bridge with a different DC voltage, each of which has a voltage of HB three times the previous HB. The inverter is also able to produce a number of higher output voltage levels and less harmonic distortion than cascade topologies, floating capacitors and diodes. This feature enables the structure to be used to compensate for the power quality of power distribution networks. Nearest Level Control (NLC) in the inverter is used to create the desired waveform. The In-Phase control method is selected to control the proposed DVR and use the synchronous reference frame (SRF) method to detect the network voltage fluctuations. To verify and validate the proposed DVR performance, simulations are carried out in the MATLAB / SIMULINK software environment, and the results indicate the optimal performance and desirability of the proposed DVR to compensate for the voltage sag, swell and flicker power distribution grids