Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title An Study on the Improved Modeling and Double Loop Controller Design for Three-Level Boost Converter
Authors Kyu-Min Lee ; Il-Song Kim
DOI 10.6113/TKPE.2020.25.6.442
Page pp.442-450
ISSN 1229-2214
Keywords DC/DC converter; Three-level boost converter; Modeling; Controller
Abstract A small-signal modeling approach for a three-level boost (TLB) converter and a design methodology for a double-loop controller are proposed in this study. Conventional modeling of TLB converters involves three state variables. Moreover, TLB converters have two operation modes depending on the duty ratio. Consequently, complex mathematical calculations are required for controller design. This study proposes a simple system modeling method that uses two state variables, unlike previous methods that require three state variables. Analysis shows that the transfer functions of the two operation modes can be expressed as identical equations. This condition means that the linear feedback controller can be applied to all operational ranges, that is, for full duty ratios. The design method for a double-loop controller using a PI controller is presented in step-by-step sequences. Simulation and experimental verifications are conducted to verify the effectiveness of the small-signal analysis and control system design.