PROJECT TITLE :

Hybrid Modulation Based Bidirectional Electrolytic Capacitor-less Three-phase Inverter for Fuel Cell Vehicles: Analysis, Design, and Experimental Results - 2017

ABSTRACT:

This paper presents a unique six-pulse low-frequency (LF) fluctuating high-voltage dc-bus-primarily based power system design for fuel cell vehicles (FCVs) application. A unique hybrid modulation theme consisting of six-pulse modulation at LF scale and changed secondary modulation and thirty threepercent pulse width modulation at high-frequency (HF) scale is proposed. Three-section ac waveforms for the propulsion system of FCVs are generated from LF fluctuating high-voltage dc bus. The proposed modulation technique significantly reduces the switching losses of the bidirectional dual-stage inverter: 1) soft-switching of each sides of the front-finish current-fed full-bridge converter is realized; and a pair of) at any moment, only one leg of back-finish 3-section inverter is switched at HF, whereas the opposite 2 legs are kept in on or off states. This tremendously reduces the bidirectional inverter's switching losses and improves the system potency. The LF fluctuating high-voltage dc bus permits the elimination of huge electrolytic dc-link capacitor, that contributes to a a lot of reliable and compact style. This paper presents the operation, analysis, and design of a bidirectional inverter implementing the proposed hybrid modulation technique. Simulation results obtained from power electronics simulation software PSIM and experimental results from the lab prototype clearly validate the effectiveness of the proposed modulation technique.