M. Tafazoli

Bio: M. Tafazoli is an academic researcher from Southern Illinois University Carbondale. The author has contributed to research in topics: Delta-sigma modulation & Bistability. The author has an hindex of 3, co-authored 5 publications receiving 47 citations. Previous affiliations of M. Tafazoli include University of Tehran.

RCS of circular carbon NANO tube antenna array

Abstract: A novel THz antenna structure, made of carbon nanotube arrays is suggested. Using CST MICROWAVE STUDIO (CST MWS), the capabilities of carbon nanotube terahertz (THz) antenna arrays have been simulated and this CNT antenna array has been fabricated.

A New Fault-Tolerant Strategy Based on a Modified Selective Harmonic Technique for Three-Phase Multilevel Converters With a Single Faulty Cell

Abstract: This paper proposes a new fault-tolerant strategy to revamp performance of three-phase multilevel converters with a single faulty switch. The proposed fault-tolerant strategy is based on the application of a modified selective harmonic elimination (SHE) technique in conjunction with the fundamental phase-shift compensation method. The proposed fault-tolerant strategy makes the most use of the converter capacity in the faulty condition, generates balanced line voltages, and eliminates a wide range of lower order harmonics to limit the total harmonic distribution of the converter voltages in the faulty condition. In this paper, first, a brief background about cascaded H-bridge multilevel converters and SHE technique is provided. Then, the proposed fault-tolerant strategy and the modified SHE technique are presented. Finally, several experimental results are provided to validate the operation of the proposed strategy.

High Performance Control of Grid Connected Cascaded H-Bridge Active Rectifier Based on Type II-Fuzzy Logic Controller with Low Frequency Modulation Technique

Abstract: This paper tries to employ a fuzzy logic (FL) controller type II to control the Cascaded H-Bridge (CHB) active rectifier. This controller has strong performance, specially, when a low switching frequency Selective Harmonic Elimination (SHE) method is used. In order to regulate all of the DC link voltages, the optimum voltage balancing strategy in the low frequency modulation technique is used in the proposed method. Finally, the performance and effectiveness of the proposed method is validated in MATLAB environment. All the simulation and result has been simulated by MATLAB software.

Unbalanced Space Vector Modulation with Fundamental Phase Shift Compensation for Faulty Multilevel Converters

Abstract: This paper proposes a new fault-tolerant strategy for the purpose of revamping the performance of three-phase multilevel (ML) converters with faulty switches. The proposed fault-tolerant strategy is based on an adaptation of the modified space vector modulation (SVM) technique to the fundamental phase-shift compensation method. The proposed fault-tolerant strategy generates balanced line-to-line voltages with increased voltage levels in the faulty condition. In this paper, first a brief background about cascaded H-bridge (CHB) ML converters and SVM technique is provided. Then the proposed fault-tolerant strategy and the modified SVM technique are presented. Finally, several experimental results are provided to validate operation of the proposed strategy.

A Fault-Tolerant Strategy Based on Fundamental Phase-Shift Compensation for Three-Phase Multilevel Converters With Quasi-Z-Source Networks With Discontinuous Input Current

Abstract: This paper proposes a new fault-tolerant strategy for a multilevel converter with an integrated impedance-source network. The proposed fault-tolerant strategy leverages the flexibility provided by the impedance-source network to implement the fundamental phase-shift compensation (FPSC) method in order to restore operation of a multilevel converter with one or more faulty switches to the prefault conditions. In case of a fault occurrence, the proposed fault-tolerant strategy makes the most use of the remaining converter capacity and generates balanced line-to-line voltages, while evenly distributing an inevitable voltage stress increase, over all converter switches. In this paper, first, a brief background about an impedance-source based cascaded H-bridge converter and a suitable modulation method for it is provided. Then, the FPSC method is explained and the proposed fault-tolerant strategy based on this method is introduced. Finally, several experimental results from a prototype converter are provided to validate the operation of the proposed strategy.