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"This book focuses on the applications of Equivalent-Small-Parameter Method (ESPM) in solving the steady-state periodic solutions, as well as stability analysis, of kinds of open-loop or closed-loop operated DC/DC converters, such as PWM, quasi-resonant and resonant ones. The analytical expressions of DC components and harmonics of state variables (inductor current and capacitor voltage) with DC/DC converters can be obtained by ESPM, which can be helpful to understand the nonlinear operating mechanism of switched-mode converters. It can also be useful for stability analysis and design for practical converters. Modeling and analysis on all kinds of DC/DC converters are introduced in detail in this book, along with a large amount of simulation or experimental waveforms to verify the correctness of the theoretical analysis based on ESPM."

"Written by experts, this book is based on recent research findings in high-frequency isolated bidirectional DC-DC converters with wide voltage range. It presents advanced power control methods and new isolated bidirectional DC-DC topologies to improve the performance of isolated bidirectional converters. Providing valuable insights, advanced methods and practical design guides on the DC-DC conversion that can be considered in applications such as microgrid, bidirectional EV chargers, and solid state transformers, it is a valuable resource for researchers, scientists, and engineers in the field of isolated bidirectional DC-DC converters."

"Pada saat ini pengembangan dan penggunaan kendaraan listrik masif dilakukan. Kendaraan listrik membutuhkan konverter DC-DC untuk menurunkan tegangan tinggi dari sumber utama — baterai besar — ke tegangan rendah (step down DC-DC converter) sehingga tegangan dapat digunakan oleh komponen - komponen yang membutuhkan tenganan rendah. Topologi konverter DC-DC yang umum digunakan adalah konverter dengan switch tunggal seperti flyback converter dan switch ganda seperti half bridge converter. Akan tetapi kedua topologi tersebut memiliki nilai voltage and current stress (spike, overshoot, dan ringing) yang tinggi dengan demikian akan menimbulkan rugi - rugi daya yang besar serta membutuhkan komponen dengan rating tegangan dan arus yang tinggi. Phase Shift Full Bridge DC-DC Converter (selanjutnya akan disebut PSFB) merupakan salah satu topologi konverter DC-DC terisolasi yang memiliki konfigurasi empat switch (full bridge / active bridge) sehingga dapat memiliki voltage and current stress yang lebih rendah dibandingkan dengan kedua topologi sebelumnya, dengan demikian dapat dihasilkan rugi - rugi daya yang lebih rendah [1]. Tegangan output PSFB ditentukan dari pergeseran fasa active bridge yang dihasilkan melalui kolaborasi keempat switch MOSFET oleh gate driver [2]. Gate driver dikendalikan oleh mikrokontroler yang sudah diporgram dengan algoritma pergeseran fasa dan juga closed loop control. Dalam karya ilmiah ini berhasil dibuat purwarupa PSFB yang dapat menghasilkan tegangan output dinamis sesuai dengan pergeseran fasa dalam active bridge. Nilai tegangan output memiliki kecenderungan meningkat dalam rentang pergeseran fasa 0º sampai 180º dan memiliki kecenderungan menurun dalam rentang pergeseran fasa 180º sampai 360º. Diperoleh juga hasil yang menunjukkan bahwa purwarupa PSFB sudah terintegrasi dengan closed loop control sehingga sistem dapat menghasilkan tegangan output sesuai dengan setpoint yang ada dalam program. Sistem dapat mempertahankan tegangan output sesuai setpoint meskipun diberikan variasi tegangan input dan variasi beban.

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Currently, the development and widespread use of electric vehicles are underway. Electric vehicles require a DC-DC converter to convert the high voltage from the main source — a large battery — to a lower voltage (step-down DC-DC converter), allowing it to be used by components that require low voltage. Commonly used topologies for DC-DC converters include single-switch converters like the flyback converter and dual-switch converters like the half-bridge converter. However, both topologies have high voltage and current stress values (spikes, overshoot, and ringing), resulting in significant power losses and the need for components with high voltage and current ratings. The Phase Shift Full Bridge DC-DC Converter (hereafter referred to as PSFB) is one of the isolated DC-DC converter topologies with a four-switch configuration (full bridge/active bridge). This configuration allows it to have lower voltage and current stress compared to the previous two topologies, thereby resulting in lower power losses [1]. The output voltage of the PSFB is determined by the phase shift of the active bridge generated through the collaboration of the four MOSFET switches controlled by a gate driver [2]. The gate driver is controlled by a microcontroller programmed with a phase shift algorithm and closed-loop control. In this scientific work, a prototype of the PSFB has been successfully developed, capable of producing dynamic output voltage in accordance with the phase shift in the active bridge. The output voltage tends to increase in the phase shift range of 0º to 180º and decrease in the range of 180º to 360º. Furthermore, results indicate that the PSFB system has been integrated with closed-loop control, enabling it to generate output voltage according to the various setpoint in the program. The system is able to maintain the output voltage according to setpoint, regardless of various of input voltages and loads."

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Pada skripsi ini dipresentasikan desain rangkaian novel dc-dc flyback converter untuk mendukung teknologi 48 volt. Kebaruan dari rangkaian ini adalah pengaplikasian parallel input seried output dan umpan balik pada dc-dc flyback converter untuk mengubah 12V DC ke 48V DC. Disamping itu penggunaan transformator pada rangkaian yang berjumlah lebih dari satu berfungsi untuk membagi beban kerja induksi magnetik pada inti transformator. Desain umpan balik memanfaatkan arduino untuk memproses sinyal umpan balik sehingga menggerakan komponen penghasil sinyal PWM berdasarkan sinyal umpan balik yang diterima dan tegangan keluaran yang dihasilkan mencapai 48 volt meskipun dilakukan variasi beban. Rangkaian usulan terdiri atas keempat model yang berbeda, yaitu model tanpa umpan balik, model arduino-TL494CN, arduino saja, dan arduino-MCP4725-TL494CN. Hasil dari penelitian ini menyatakan model arduino-MCP4725-TL494CN memiliki presisi yang tinggi yaitu nilai defiasi yang paling rendah 0.02765 %⁄int dan tidak mengalami overshoot pada inisiasi rangkaian.

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This essay presented dc-dc flyback converter for supporting 48 volt technology. This circuit merge parallel input seried output and feedback application. The new design development consist of parallel input seried output and feedback in dc-dc flyback converter to converter 12V DC to 48 V DC. Aside that, the function of using transformer more than one in circuit is for splitting magnetic induction workload for transformer core. Feedback design using arduino is for proccessing feedback signal so that driving PWM generator component based on received feedback signal and output voltage reach at 48 volt even the load is changing. The proposed circuit consist of four different model, that are no feedback model, arduino-TL494CN model, arduino only, and arduino-MCP4725-TL494CN model. Result of this research stated arduino-MCP4725-TL494CN model has the lowest deviation value 0.02765 %⁄int and preventing overshoot at circuit initiation.

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"This book presents a tutorial review of van der Pol model, a universal oscillator model for the analysis of modern RC−oscillators in weak and strong nonlinear regimes. A detailed analysis of the injection locking in van der Pol oscillators is also presented. The relation between the van der Pol parameters and several circuit implementations in CMOS nanotechnology is given, showing that this theory is very useful in the optimization of oscillator key parameters, such as: frequency, amplitude and phase relationship. The authors discuss three different examples: active coupling RC−oscillators, capacitive coupling RC−oscillators, and two-integrator oscillator working in the sinusoidal regime.· Provides a detailed tutorial on the van der Pol oscillator model, which can be the basis for the analysis of modern RC−oscillators in weak and strong nonlinear regimes;· Demonstrations the relationship between the van der Pol parameters and several circuit implementations in CMOS nanotechnology, showing that this theory is a powerful tool in the optimization of key oscillator parameters;· Provides three circuit prototypes implemented in modern CMOS nanotechnology in the GHz range, with applications in low area, low power, low cost, wireless sensor network (WSN) applications (e.g. IoT, BLE)."

"Peralatan-peralatan listrik sekarang ini seperti lampu, telah menerapkan teknologi Switched Mode Power Supply (SMPS) pada rangkaian catu dayanya dalam mengkonversi tegangan AC menjadi tegangan DC. Proses konversi pada beban elektronika ini menimbulkan adanya rugi-rugi konversi. Sehingga muncul peluang DC microgrid untuk meminimalisir rugi-rugi daya yang dimanfaatkan untuk mensuplai beban - beban AC tersebut.Seiring dengan berjalannya waktu, DC microgrid mulai di ujicoba untuk diparalel dengan DC microgrid lainnya, agar dapat ikut membantu membagi beban-beban penggunaan oleh konsumen, dan menjaga agar ketersediaan listrik tetap terjaga apabila terjadi gangguan pada salah satu DC microgrid.Ketika dilakukan paralel DC-DC konverter dengan seluruh komponen dan peralatan yang identik didapatkan yaitu terjadi ketidakseimbangan dalam pembagian arus antar konverter terhadap beban yang digunakan. Ketidakseimbangan arus ini terjadi karena faktor toleransi komponen dalam konverter yang tidak mungkin sama. Faktor lain yang pada akhirnya menyebabkan perbedaan arus adalah faktor penggunaan kabel atau konduktor listik dimana karakteristik kabel yang tidak identik dari konverter ke beban akhir.Kemudian muncul penggunaan komponen pasif sebagai penyeimbang arus berupa induktor toroid, sehingga menjadikan selisih keseimbangan arus antar konverter menjadi lebih baik dan efisien.

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Current electrical equipment such as lights, have implemented technology Switched Mode Power Supply (SMPS) on the power supply circuit converts the AC voltage into DC voltage. The conversion process in this electronic load losses gave rise to conversion. So there is an opportunity DC microgrid to minimize power losses are used to supply the AC load.

Over the time, the DC microgrid started in trials for paraller DC microgrid with others, in order to help to divide the load by consumers used, and to keep the availability of electricity is maintained in the event of interference on one DC microgrid.

When done parallel DC-DC Converter with all components and equipment that are identical obtained is an imbalance in current sharing between the konverter to the load being used. This occurs because the current imbalance tolerance factor components in konverter that not be the same. Another factor that ultimately led to the current difference is a factor of the use of wires or conductor electric cable in which the characteristics are not identical from the konverter to the load end.

Then came the use of passive components such as balancing current toroid inductors, making the difference between the current balance konverter becomes better and more efficient."

"This book describes a new way to design and utilize Instrumentation Amplifiers (IAs) by taking advantages of the current-mode (CM) approach. For the first time, all different topologies of CMIAs are discussed and compared, providing a single-source reference for instrumentation and measurement experts who want to choose a topology for a specific application. The authors also explain major challenges in designing CMIAs, so the book can be useful for anyone studying instrumentation amplifiers, and even other analog circuits. Coverage also includes various CM signal processing techniques employed in CMIAs, and applications of the CMIAs in biomedical and data acquisition are demonstrated. "

"This book addresses the design challenges in near-field wireless power transfer (WPT) systems, such as high efficiency, compact size, and long transmission range. It presents new low-profile designs for the TX/RX structures using different shapes of defected ground structures (DGS) like (H, semi-H, and spiral-strips DGS). Most near-field WPT systems depend on magnetic resonant coupling (MRC) using 3-D wire loops or helical antennas, which are often bulky. This, in turn, poses technical difficulties in their application in small electronic devices and biomedical implants. To obtain compact structures, printed spiral coils (PSCs) have recently emerged as a candidate for low-profile WPT systems. However, most of the MRC WPT systems that use PSCs have limitations in the maximum achievable efficiency due to the feeding method. Inductive feeding constrains the geometric dimensions of the main transmitting (TX)/receiving (RX) resonators, which do not achieve the maximum achievable unloaded quality factor. This book will be of interest to researchers and professionals working on WPT-related problems."