Design and implementation of 30kW 200/900V LCL modular multilevel based DC/DC converter for high power applications

Abstract

This paper presents the design, development and testing of a 30kW, 200V/900V modular multilevel converter (MMC) based DC/DC converter prototype. An internal LCL circuit is used to provide voltage stepping and fault tolerance property. The converter comprises two five level MMC based on insulated gate bipolar transistors (IGBTs) and metal oxide semiconductor field effect transistor (MOSFET). Due to low number of levels, selective harmonic elimination modulation (SHE) is used, which determines the switching angles in such a way that third harmonic is minimized whereas the fundamental component is a linear function of the modulation index. In addition, instead of using an expensive control board, three commercial control boards are embedded. This is required to implement the sophisticated DC/DC converter control algorithm. Simulation and experimental results are presented to demonstrate the converter performance in step up and down modes.

The Generalization of Bidirectional Dual Active Bridge DC/DC Converter Modulation Schemes: State-of-the-Art Analysis under Triple Phase Shift Control

“…The use of DAB design for a minimum weight for airborne wind turbine systems using state-of-the-art power-switching device silicon carbide (SiC), was analyzed in [13]. The application of DAB in medium voltage (MVDC) distribution and HVDC network is presented in [14].…”

“…The primary emphasis of recent research on dual active bridge (DAB) converters has been on enhancing efficiency through the development of modulation control strategies [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26], close loop control [27][28][29][30][31], converter circuit topology [26,27] and use of low loss switching devices [32,33]. The modulation control scheme for DAB converters has emerged as a significant research area, with a focus on optimizing existing modulation methods.…”