A closed-loop control of high power LLC Resonant Converter for DC-DC applications

Author

Gopiyani, Alpa ; Patel, Vinod

fYear

2011

fDate

8-10 Dec. 2011

Firstpage

1

Lastpage

6

Abstract

This paper presents a new closed-loop control strategy applied to half-bridge high power LLC Resonant Converter applicable in DC-DC applications and can be applied for other applications also. A new control circuit is designed and implemented for the high power LLC converter. A closed-loop variable frequency control through VCO is analyzed through PI Controller. Due to Zero Voltage Switching (ZVS) technique the turn-on losses of both the switches (IGBTs) in half-bridge are reduced and ZVS can be achieved for the entire control range in close-loop. Validity of PI controller and control circuit in closed-loop are verified with software simulation results for wide input and load range. A hardware prototype rated at 2.1 kW has been built with DSP TMS320F2811 and hardware results are presented to verify the control strategy. Practical results with DC-DC converter match with the simulated results and performance of control circuit is verified and tested practically with input voltage variations and load changes at different references.

Keywords

DC-DC power convertors; PI control; closed loop systems; control system synthesis; digital signal processing chips; frequency control; power semiconductor switches; resonant power convertors; voltage-controlled oscillators; zero voltage switching; DC-DC converter application; DSP TMS320F2811 processing; IGBT switch; PI Controller; VCO; closed-loop control strategy; closed-loop variable frequency control; control circuit design; due to ZVS technique; due to zero voltage switching technique; half-bridge high power LLC resonant converter; input voltage variation; power 2.1 kW; software simulation; turn-on loss; Control systems; Frequency control; Frequency conversion; Resonant frequency; Voltage control; Voltage-controlled oscillators; Zero voltage switching; LLC Resonant Converter; PI controller; VCO; ZVS; closed-loop control;

fLanguage

English

Publisher

ieee

Conference_Titel

Engineering (NUiCONE), 2011 Nirma University International Conference on

Conference_Location

Ahmedabad, Gujarat

Print_ISBN

978-1-4577-2169-4

Type

conf

DOI

10.1109/NUiConE.2011.6153284

Filename

6153284