| PhD Viva

Name of the Speaker: Mr. Nagesha C (EE20D009)
Guide: Prof. Lakshminarasamma N
Online meeting link: https://meet.google.com/qyi-ftbu-apv
Date/Time: 4th October 2024 (Friday), 3:00 PM
Title: HIGH GAIN RESONANT DC-DC CONVERTERS FOR INDUSTRIAL APPLICATIONS

Abstract :

The thesis presents the research work on resonant converter for various industrial applications such as battery to grid application, ev charging, telecom power supply and data center power supply. The work presents detailed steady state analysis, generalized design guidelines for selection of LC, LLC and LCLC resonant tank networks. A small signal modeling in d-q reference frame is proposed for LCLC resonant converter. The model is verified in 1 kW hardware prototype. The extension of model for LC and LLC is also detailed in this work. A bidirectional reconfigurable LCLC resonant converter is proposed for flow battery to grid application. The converter is able to establish 800V dc bus from 24 V-54 V input in forward power transfer mode by configuring secondary bridge to active voltage double network. During reverse power transfer the secondady bridge is reconfigured to full bridge to charge the battery to maximum voltage of 54 V. The converter is validated with 1 kW prototype, a peak power conversion efficiency of 96 ℅ observed during converter operation. Efficiency improvement is the another important aspect typically addresses with synchronoua rectification. A novel predictive synchronous rectification scheme is proposed for resonant DC-DC converter. The proposed scheme eliminates the need for high bandwidth current sensors, thus reduces cost and complexity associated with it. The proposed predictive scheme is verified in 1 kW hardware prototype. The proposed scheme able to track the turn on and turn off instants precisely with the timing error < 3% of the synchronous MOSFET on time throughout the operating range.