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Contribution à l'étude de la tolérance de pannes de convertisseurs multiniveaux en pont en H

Abstract : Ensuring service continuity in safety-critical applications is indispensable. In some of these applications, the multilevel inverters play a vital role. Hence, employing a multilevel converter with fault tolerant feature is of great importance. In this regard, a fault tolerant five-level Neutral Point Clamped (NPC) inverter is proposed in this research work. The proposed fault diagnosis algorithm is based on failure mode analysis, which is a logic based approach. The realization of this strategy does not require any component modeling and complicated calculations. Although switches are more fragile than clamping diodes, clamping diodes are also subjected to breakdown. Hence, identification of a defective clamping diode is also studied in this research work. Moreover, for fault detection procedure, a voltage quantifier is proposed to avoid any misdiagnosis arising from measurement errors and voltage drop in the circuit. Following to the fault diagnosis, the proposed fault tolerant strategy aims to restore the rated voltage and current at the inverter terminal in the presence of an open-circuit fault in a switch or in a clamping or anti-parallel diode. Compared with healthy operation, harmonic content of the terminal voltage and current is not increased. The proposed fault tolerant structure does not include any contactor or bidirectional switch, which allows fast triggering of fault tolerant operation. The simulation and experimental results are presented to validate the effectiveness of the proposed approaches. A fault is detected in 20 µs and localized between 20 and 60 µs after occurrence, depending on the faulty semiconductor (switch or clamping diode).
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https://hal.univ-lorraine.fr/tel-03335474
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Submitted on : Monday, September 6, 2021 - 11:31:05 AM
Last modification on : Tuesday, September 7, 2021 - 3:23:48 AM

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  • HAL Id : tel-03335474, version 1

Citation

Sajjad Ahmadi. Contribution à l'étude de la tolérance de pannes de convertisseurs multiniveaux en pont en H. Sciences de l'ingénieur [physics]. Université de Lorraine, 2021. Français. ⟨NNT : 2021LORR0026⟩. ⟨tel-03335474⟩

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