کنفرانس مهندسی برق ایران

صفحه اصلی / سی و سومین کنفرانس بین المللی مهندسی برق

A Fault-Tolerant Strategy for Load Non-Interrupted Power Supply in CHB Converter Based on Modified Level Shift PWM

نویسندگان :

Farzaneh Aslani-Gaznag¹ Armin Panahi² Yousef Neyshabouri³

1- دانشگاه ارومیه 2- دانشگاه ارومیه 3- دانشگاه ارومیه

کلمات کلیدی :

Multilevel converter،Cascaded H-bridge (CHB)،Active rectifier،Fault tolerance

چکیده :

This paper introduces a fault-tolerant control strategy for single-phase Cascaded H-Bridge (CHB) in rectifier application that ensures uninterrupted operation despite semiconductor power switch failures. The proposed method utilizes the redundant switching states in the CHB topology to bypass faulty switches, maintaining power supply to the load without requiring disconnection of DC loads or bypassing the entire affected cells. To realize the mentioned objectives, the faulty H-bridge cell is reconfigured considering operational constraints for the loads continuous power supply and proper functionality under faults. A modified level-shifted PWM technique is presented for post-fault operation through which the balance of DC capacitors voltages is maintained. Simulation results for a three-cell CHB rectifier validate the technique's effectiveness in balancing DC-link voltages, uninterrupted power supplying to the DC loads, and maintaining low total harmonic distortion in the AC side, even under single or multiple switch faults and unbalanced load conditions.