Boost Multilevel Cascade Inverter for Hydrogen Fuel Cell Light Railway Vehicles

• Published in: IEEE transactions on industrial electronics (1982) Vol. 69; no. 8; pp. 7837 - 7847
• Main Authors: Krastev, Ivan, Tricoli, Pietro
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-08-2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Boost converters; Capacitors; Converters; Energy conversion; fuel cell vehicles; Fuel cells; Hydrogen fuels; Induction motors; Inductors; Inverters; Legged locomotion; Light rail transportation; modular multilevel converters; Multilevel; Traction; traction drives; Trains; Vehicles; Voltage control; Voltage source inverter fed induction motors; Waveforms
• ISSN: 0278-0046; 1557-9948
• DOI: 10.1109/TIE.2021.3105992

This article presents a ground breaking traction drive for fuel cell-powered light rail vehicles based on a multilevel cascade converter with H-bridge cells. The converter provides dc-ac power conversion with unique buck-boost capability to compensate for the variation of fuel cell terminal voltage with the load power. In comparison to a conventional boost inverter, based on the cascade connection of a boost dc-dc converter and a voltage source inverter, the proposed converter has the significant benefits of much smaller inductor size, lower dc side current ripple, and multilevel voltage waveforms at the ac output. This article presents the converter modeling and design of the boost inductor and submodule capacitors, taking into account the full speed range of the motor. The concept has been fully validated on a bespoke experimental prototype driving an induction motor, showing the suitability of the proposed converter as a traction drive for hydrogen-powered rail vehicles.