Design and Experimental Validation Of FPGA Based Digital Control Scheme Of The Nearest Level Modulation Method For Modular Multilevel Converter Topology

Year 2025, Volume: 4 Issue: 1, 44 - 58, 18.02.2025

Mehmet Kurtoğlu , Fatih Eroğlu , Ahmet Mete Vural

https://doi.org/10.62520/fujece.1457671

Abstract

Modular multilevel converter (MMC) has become a preferable circuit topology for industrial applications, where the nearest level modulation (NLM) technique is mostly used to control the arm voltages of the MMC. Implementation of the NLM method on MMC topology using digital control techniques is gaining importance among researchers because of flexible design, full controllability, re-configurable property and modular realization. In order to achieve this aim, field programmable gate arrays (FPGAs) are preferred thanks to their benefits such as high speed performance and parallel processing ability. Accordingly, in this article, FPGA based control scheme of the NLM method was proposed for single-phase five-level MMC topology. In this context, very high-speed integrated circuit hardware description language (VHDL) modules were designed to achieve the proposed architectural design of the NLM method by presenting each VHDL module and algorithm used in the implementation. The architectural steps of the FPGA realization of the NLM method were presented in detail. Gate signals of the switching devices of the MMC topology were observed in simulation environment. Finally, in order to validate the applicability of the digital control scheme of the NLM method, an experimental setup was built using single-phase five-level MMC topology and experimental findings were presented. According to the obtained results of this study, the outcomes including gate signals, arm voltages and output voltages with currents were presented for various modulation index values using the RL load.

Keywords

Multilevel converter, Modulation, Field programmable gate array, Digital control

Ethical Statement

Hazırlanan makalede etik kurul izni alınmasına gerek yoktur.

Modüler Çok Seviyeli Dönüştürücü Topolojisi İçin En Yakın Seviye Modülasyon Yönteminin FPGA Tabanlı Dijital Kontrol Şemasının Tasarımı ve Deneysel Doğrulaması

Abstract

Modüler çok seviyeli dönüştürücü (MÇD), en yakın seviye modülasyonu (ESM) tekniğinin çoğunlukla MÇD'nin kol gerilimlerini kontrol etmek için kullanıldığı endüstriyel uygulamalar için tercih edilen bir devre topolojisi haline gelmiştir. ESM yönteminin MÇD topolojisi üzerinde dijital kontrol teknikleri kullanılarak uygulanması; esnek tasarım, tam kontrol edilebilirlik, yeniden yapılandırılabilir özellik ve modüler gerçekleştirme nedeniyle araştırmacılar arasında önem kazanmaktadır. Bu amaca ulaşmak için yüksek hız performansı ve paralel işlem yapabilme gibi avantajları sayesinde alanda programlanabilir kapı dizileri (FPGA'lar) kullanılmaktadır. Buna göre, bu makalede, tek fazlı beş seviyeli MÇD topolojisi için ESM yönteminin FPGA tabanlı kontrol şeması önerilmiştir. Bu bağlamda, çok yüksek hızlı tümleşik devre donanım tanımlama dili (VHDL) modülleri, uygulamada kullanılan her bir VHDL modülü ve algoritması sunularak ESM yönteminin önerilen mimari tasarımını gerçekleştirmek için tasarlanmıştır. ESM yönteminin FPGA'da gerçekleştirilmesinin mimari adımları ayrıntılı olarak sunulmuştur. MÇD topolojisindeki anahtarlama elemanlarının kapı sinyalleri simülasyon ortamında gözlemlenmiştir. Son olarak, ESM yönteminin dijital kontrol şemasının uygulanabilirliğini doğrulamak için, tek fazlı beş seviyeli MÇD topolojisi kullanılarak bir deney düzeneği oluşturulmuş ve deneysel bulgular sunulmuştur. Bu çalışmada elde edilen sonuçlara göre, RL yükü kullanılarak kapı sinyalleri, kol gerilimleri ve çeşitli modülasyon indeksi değerleri için çıkış gerilimleri ile akımları içeren sonuçlar sunulmuştur.

Keywords

Çok seviyeli dönüştürücü, Modülasyon, Alanda programlanabilir kapı dizisi, Dijital kontrol

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