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"Telah dilakukan penelitian multilevel inverter dengan tingkatan tujuh level. Perkembangan energi terbarukan yang semakin meluas seperti penggunaan fuel cell pada sistem pembangkit distribusi memerlukan adanya teknologi inverter yang lebih efisien. Multilevel inverter H-Bridge merupakan inverter yang umum digunakan dengan tujuan untuk mereduksi nilai dari Total Harmonic Distortion yang mempengaruhi bentuk gelombang tegangan dan arus keluraran di beban. Dalam mencapai sistem 7 level diperlukan susunan seri dari tiga sel H-Bridge. Hal ini menjadi pertimbangan untuk dikembangkan desain baru dengan melihat bahwa susunan seri H-Bridge merupakan sistem yang bulky dan menggunakan banyak saklar sehingga menghasilkan rugi-rugi pensaklaran. Di dalam paper ini diajukan desain baru yang dinamakan dengan topologi T-H bridge inverter yang merupakan kombinasi dari inverter H-Bridge dan T-type. Kelebihan dari T-H bridge inverter untuk satu sel mampu menghasilkan 7 level tegangan dan jumlah saklar yang digunakan lebih sedikit dibanding bulky H-Bridge. Skema kendali pada topologi T-H bridge inverter menggunakan Phase Shifted Sinusoidal Pulse Width Modulation. Adapun frekuensi switching yang digunakan yakni 5 kHz. Simulasi dibangun dengan Simulink/Matlab R2018a. Hasil simulasi menunjukkan bahwa nilai THD arus pada topologi tiga sel H-Bridge dan T-H bridge inverter yakni 2,33% dan 2,31% secara berturut-turut pada frekuensi fundamental 50 Hz.

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Multilevel inverter research has been carried out with seventh level. The development of renewable energy that is increasingly widespread, such as the use of fuel cell in distributed generation systems, requires more efficient inverter technology. Multilevel inverter H-Bridge is an inverter that is commonly used with the aim of reducing content of Total Harmonic Distortion that affects the output voltage and current waveform in the load. Achieving a 7-level system requires a series arrangement of three H-Bridge cells. This is a consideration for developing a new design by considering that the H-Bridge series arrangement is a bulky system and uses many switches, resulting in a switching losses. This paper proposes a new design called the T-H bridge inverter topology which is a combination of the H-Bridge and T-type inverters. The advantage of the T-H bridge inverter is that for one cell it is able to produce 7th voltage level and the number of switches used is less than the bulky H-Bridge. Control scheme of T-H bridge inverter topology is by Phase Shifted Sinusoidal Pulse Width Modulation. The switching frequency used is 5 kHz. The simulation is built with Simulink/Matlab R2018a. The simulation results show that the current THD content in the three-cell topology of the H-Bridge and the T-H bridge inverter are 2,33% and 2,31%, respectively, at a fundamental frequency of 50 Hz."

"The purpose of this book is to distinguish the single-de-source multilevel inverter topologies and to teach their control, switching and voltage balancing. It includes new information on voltage balancing and control of multilevel inverters.The book answers some important questions about the revolution of power electronics converters:1- Why multilevel inverter are better than 2-level ones?2- Why single-de-source multilevel inverters are a matter of interest?3- What are the redundant switching states and what do they do?4- How to use redundant switching states in control and voltage balancing?5- What are the applications of single-de-source multilevel inverters?"

"Motor sinkron magnet permanen (PMSM) telah mendapatkan perhatian yang signifikan dalam berbagai aplikasi industri, rumah tangga, dan kendaraan listrik karena efisiensi, power density, dan keandalannya yang unggul. Baru-baru ini, sistem perkeretaapian berbasis PMSM juga menarik minat yang semakin besar karena rentang kecepatan yang luas dan desain yang compact. Strategi pengendalian kecepatan konvensional, seperti pengendali proportional-integral (PI) banyak digunakan dalam sistem PMSM karena stukturnya yang sederhana dan kokoh. Namun, nilai gain PI yang tetap membatasi kemampuan adaptasi dalam kondisi operasi yang dinamis dan nonlinier, sehingga menghasilkan respons pengendalian yang statis dan kinerja yang kurang optimal. Untuk mengatasi keterbatasan ini, strategi pengendalian nonlinier tingkat lanjut seperti adaptive control, sliding mode control (SMC), model predictive control (MPC), dan metode berbasis neural network telah diteliti. Meskipun menjanjikan, adaptive control memerlukan perhitungan kompleks dan rentan terhadap ketidaksesuaian parameter. SMC memiliki kelemahan utama berupa chattering, yang dapat menyebabkan keausan mekanis, rugi daya, dan peningkatan sensitivitas terhadap gangguan. Selain itu, perancangan sliding surface dan tuning gain kontrol cukup kompleks karena memerlukan pemodelan sistem yang presisi. Neural network (NN) menawarkan kontrol adaptif, tetapi membutuhkan sumber daya komputasi yang tinggi, yang menjadi kendala bagi sistem tertanam berbiaya rendah dengan kemampuan processing yang terbatas. Untuk mengatasi hal tersebut, pengendali single-neuron proporsional-integral (SN-PI) muncul sebagai alternatif yang menjanjikan, dengan kemampuan processing yang terbatas. Untuk mengatasi hal tersebut, pengendali single-neuron proporsional-integral (SN-PI) muncul sebagai alternatif yang menjanjikan, dengan kemampuan self-tuning, respons dinamis yang lebih baik, adaptabilitas yang tinggi terhadap variasi sistem, serta kemudahan implementasi. Dalam studi ini, pengendali SN-PI diimplementasikan pada loop pegendalian kecepatan PMSM, di mana gain kontrol disesuaikan secara dinamis guna mengoptimalkan kinerja dalam berbagai kondisi. Selain itu, diode-clamped multilevel inverter (DCMLI) digunakan untuk meningkatkan kualitas daya dan efisiensi inverter. Dibandingkan dengan inverter dua tingkat konvensional, DCMLI menawarkan distorsi harmonik yang lebih rendah, dv/dt stress yang berkurang, electromagnetic compatibility (EMC) yang lebih baik, serta pemanfaatan tegangan yang lebih optimal, sehingga cocok untuk aplikasi motor drive berkinerja tinggi. Hasil simulasi menunjukkan bahwa pengendali SN-PI memberikan respons dinamis yang lebih cepat dan robust dibandingkan pengendali PI konvensional, sementara DCMLI sembilan tingkat secara efektif mengurangi distorsi harmonik, sehingga meningkatkan kualitas daya dan efisiensi sistem.

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Permanent magnet synchronous motors (PMSMs) have garnered significant interest across industrial, domestic, and electric vehicle implementations due to their excellent efficiency, power density, and reliability. Recently, PMSM-driven railway systems have also attracted growing interest due to their wide speed range and compact design. Conventional speed control strategies, such as the proportional-integral (PI) controller, are commonly employed in PMSM systems due to their simplicity and robustness. However, the fixed PI gains limit adaptability under dynamic and nonlinear operating conditions, resulting in a static control response and suboptimal performance. To overcome these limitations, advanced nonlinear control strategies, including adaptive control, sliding mode control (SMC), model predictive control (MPC), and neural network-based control, have been investigated. Despite their potential, adaptive control demands complex computations and is vulnerable to parameter mismatches. SMC has a main drawback in the form of chattering, which can cause mechanical wear, power losses, and increased sensitivity to noise. Additionally, designing an appropriate sliding surface and tuning control gains is complex, requiring precise system modeling. Neural networks (NNs) offer adaptive control but demand high computational resources, which poses challenges for low-cost embedded systems with limited processing capabilities.. To overcome this, the single-neuron proportional-integral (SN-PI) controller emerges as a promising alternative, offering self-tuning capabilities, enhanced dynamic response, improved adaptability to system variations, and ease of implementation. In this paper, an SN-PI controller is implemented in the speed-control loop of the PMSM, dynamically adjusting control gains to optimize performance in varying conditions. Additionally, a diode-clamped multilevel inverter (DCMLI) is employed to enhance the power quality. Compared to conventional two-level inverters, DCMLIs offer lower harmonic distortion, reduced dv/dt stress, improved electromagnetic compatibility (EMC), and better voltage utilization, making them suitable for high-performance motor drive applications. The simulation results confirm that the SN-PI controller delivers faster and more robust dynamic responses over the conventional PI controller, while the nine-level DCMLI effectively reduces harmonic distortion, enhancing power quality and system efficiency. "