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Abstrak :
Telah dibuat Capacitance Meter yang merupakan alat ukur untuk kapasitor nonpolar. Karakteristiknya antara lain, tingkat kesalahan 1% pada skala maksimum 40 pF (piko farad), jangkauannya 3 dekade, derau dan arus drift rendah. Secara praktis (implementatif), mudah dibuat, menggunakan rangkaian op amp yang umum, rangkaian dapat di-pra implementasi-kan pada protoboard dalam waktu singkat (hitungan menit), memecahkan solusi kecepatan bagi kapasitor berharga kecil.

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It had been made a Capacitance Meter which is the measurement instrument for non-polar capacitors. It has characteristics: 1% error on maximum scale 40 pF (picofarad), 3 decades of range, low noise and drift. Practically, it is easy to construct, using common op amp circuitry, can breadboard it in minutes. It solves the speed problem for small capacitors.

Abstrak :
Semakin meningkatnya kebutuhan dan kesadaran akan pemakaian energi baru dan terbarukan (EBT) memaksa piranti penyimpanan energi untuk bekerja dengan lebih baik. Melalui penelitian ini, dihasilkan kapasitor lithium-ion (KLI) dengan kapasitas yang lebih baik dari penelitian sebelumnya. Pada penelitian ini, kapasitor lithium ion setengah sel disusun menggunakan elektroda berbahan karbon aktif dengan memanfaatkan katoda berbahan dasar green coke. Pengujian BET menunjukkan bahwa proses aktivasi dapat menghasilkan karbon aktif dengan luas permukaan yang sangat tinggi, mencapai  2024 m²/g. Sementara pengujian elektrokimia KLI menunjukkan bahwa semakin tinggi SSA, maka kapasitasnya menjadi lebih besar, dan pada penelitian ini, dicapai energi spesifik sebesar  0,4256 Wh/kg dan daya spesifik 1,7024 W/kg dengan kapasitas KLI 25 mAH. ......The increasing need and awareness of the use of new and renewable energy forces energy storage devices to work better. Through this research, lithium-ion capacitors are produced with better capacity than previous studies. In this study, half-cell lithium ion capacitors (LIC) were arranged using electrodes made from activated carbon using green coke-based cathodes. BET testing shows that the activation process can produce activated carbon with a very high spesific surface area (SSA), reaching 2024 m²/g. While LIC's electrochemical testing showed that the higher the SSA, the greater the capacity, and in this study, a specific energy of 0.4256 Wh/kg and a specific power of 1.7024 W/kg and a LIC of 25 mAH was achieved.

Abstrak :
Peningkatan penggunaan akan energi terbarukan yang ramah lingkungan menjadi alasan dalam perkembangan penelitian mengenai sistem penyimpan energi. Kepadatan daya dan energi menjadi salah satu faktor penentu pemilihan jenis sistem penyimpan energi. Kapasitor lithium ion (KLI) menjadi salah satu alternatif untuk menjawab kekurangan kepadatan daya pada baterai lithium ion (BLI) dan kepadatan energi pada superkapasitor. Nilai kapasitansi sebuah KLI dipengaruhi oleh karakteristik material katoda berupa luas spesifik permukaan, pori, dan kandungan unsur pada karbon aktif. Penelitian dan pengembangan karbon aktif berbasis biomassa sebagai material elektroda KLI telah menarik banyak perhatian dari para peneliti karena sumber daya biomassa yang melimpah, termasuk limbah tongkol jagung. Urgensi untuk menemukan alternatif karbon yang berbahan murah dan sederhana dapat diperoleh dengan mensintesis limbah tongkol jagung yang berlimpah dan cocok dengan sifat karbon. Penggunaan agen aktivator kimia selama proses aktivasi sangat penting untuk menghasilkan karbon aktif yang diinginkan, termasuk luas permukaan yang tinggi dan daya konduksi listrik yang baik. Di antara berbagai agen kimia, KOH dan ZnCl2 telah banyak digunakan mensintesis karbon aktif. Pada penelitian ini, karbon aktif berbahan tongkol jagung dengan variasi agen aktivator KOH dan ZnCl2 serta variasi rasio karbon dengan agen aktivator disintesis sebagai material katoda KLI dan dianalisis pengaruhnya terhadap kinerja KLI. Scanning electron microscopy (SEM), energy dispersive x-ray (EDX), Brunauer-Emmett-Teller (BET), serta Raman spectra digunakan untuk mengkarakterisasi karbon aktif. Hasil pengujian menunjukkan semua sampel memiliki pori berukuran mikro yang merata serta kandungan unsur karbon di atas 80%. Pori dengan ukuran terkecil terlihat pada sampel CACK12 dengan ukuran 0.2 µm. Luas permukaan karbon aktif berbahan tongkol jagung yang didapat baik dari agen aktivator KOH dan ZnCl2 dengan variasi karbon dan agen aktivator 1:3 (CACK13 dan CACZ13) tidak jauh berbeda yaitu: di kisaran nilai 800 m2/g. Kristalit yang terbentuk pada CACK dan CACZ berupa karbon amorf yang padat. Sampel karbon aktif yang dibuat selanjutnya disintesis menjadi katoda KLI dengan LTO sebagai material anodanya. Pengujian elektrokimia dilakukan melalui cyclic-voltammetry (CV) dan charge discharge (CD). Dari hasil pengujian didapat nilai kapasitansi spesifik tertinggi pada KLI-K3 dengan nilai 28,04 F/g dengan energi spesifik112,14 Wh/kg dan daya spesifik 1032.69 W/kg.

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The enhancement of renewable energy use which is environmentally friendly is the reason in the development of research on energy storage systems. Power and energy density is one of the determining factors in choosing the type of energy storage system. Lithium ion capacitors (LIC) are an alternative to answer the lack of power density in lithium ion batteries (LIB) and energy density in supercapacitors. The capacitance value of a LIC is influenced by the characteristics of the cathode material such as specific surface area, pore, and elemental content in activated carbon. The research and development of biomass-based activated carbon as a LIC electrode material has attracted much attention from researchers because of its abundant biomass resources, including corncob waste. The urgency to find carbon alternatives that are cheap and simple can be obtained by synthesizing corn cobs waste that is abundant and suitable with carbon properties. The use of chemical activator agents during the activation process is very important to produce the desired activated carbon, including high surface area and good electrical conductivity. Among various chemical agents, KOH and ZnCl2 have been widely used to synthesize activated carbon. In this study, activated carbon made from corncob with variations of activator agents KOH and ZnCl2 and variations in the ratio of carbon with activator agents were synthesized as LIC cathode material and analyzed for their effect on LIC performance. Scanning electron microscopy (SEM), energy dispersive x-ray (EDX), Brunauer-Emmett-Teller (BET), and Raman spectra are used to characterize activated carbon. The test results show all samples have a uniform micro-sized pore and carbon element content above 80%. The surface area of activated carbon made from corn cobs obtained from both KOH and ZnCl2 activator agents with carbon variations and 1: 3 activator agents (CACK13 and CACZ13) is not much different, namely: in the range of 800 m2 / g. The crystallites formed in CACK and CACZ are solid amorphous carbon. The activated carbon samples were then synthesized into KLI cathodes with LTO as the anode material. Electrochemical testing is done through cyclic-voltammetry (CV) and charge discharge (CD). From CV result KLI-K3 has the biggest specific capacitance 28,04 F/g with specific energy 112,14 Wh/kg and specific power 1032.69 W/kg.

Abstrak :
In this work we derive asymptotically stabilizing control laws for electrical power systems using two nonlinear control synthesis techniques. For this transient stabilization problem the actuator considered is a power electronic device, a controllable series capacitor (CSC).

Abstrak :
This is the first of a two-volume work covering the electrical principles syllabuses of all the major examining bodies including City & Guilds of London Institute's electrical craft courses. It is also suitable for a wide range of other courses, including the first three years of the BTEC electrical series. Great care has been taken to ensure that the text fully covers the content of the syllabuses concerned, both as published and as interpreted by the examiners in the past. The book is well illustrated with almost 200 line diagrams and photographs. Theories are explained with the help of almost 100 worked examples, an important aid to understanding the practical applications, and there are more than 300 graded exercises for which numerical answers are provided as well as nearly 250 multiple choice questions with solutions. These features make the book ideal as a class text as well as being particularly suitable for private study. A complete list of symbols, abbreviations and units is included, along with eight tables of relevant data and introduction to SI units, this system being used throughout. Each chapter concludes with a summary of the formulas introduced in it. This book will also be useful to practicing technicians wishing to extend their grasp of electrical principles to meet the rapidly expanding requirements of the industry.

Abstrak :
This is the second of a two-volume work covering the electrical principles syllabuses of all the major examining bodies including City & Guilds of London Institute's electrical craft courses. It is also suitable for a wide range of other courses, including the first three years of the BTEC electrical series. Great care has been taken to ensure that the text fully covers the content of the syllabuses concerned, both as published and as interpreted by the examiners in the past. The book is well illustrated with almost 200 line diagrams and photographs. Theories are explained with the help of almost 100 worked examples, an important aid to understanding the practical applications, and there are more than 300 graded exercises for which numerical answers are provided as well as nearly 250 multiple choice questions with solutions. These features make the book ideal as a class text as well as being particularly suitable for private study. A complete list of symbols, abbreviations and units is included, along with eight tables of relevant data and introduction to SI units, this system being used throughout. Each chapter concludes with a summary of the formulas introduced in it. This book will also be useful to practicing technicians wishing to extend their grasp of electrical principles to meet the rapidly expanding requirements of the industry.

Abstrak :
This book addresses the need for energy-efficient amplifiers, providing gain enhancement strategies, suitable to run in parallel with lower supply voltages, by introducing a new family of single-stage cascode-free amplifiers, with proper design, optimization, fabrication and experimental evaluation. The authors describe several topologies, using the UMC 130 nm CMOS technology node with standard-VT devices, for proof-of-concept, achieving results far beyond what is achievable with a classic single-stage folded-cascode amplifier. Readers will learn about a new family of circuits with a broad range of applications, together with the familiarization with a state-of-the-art electronic design automation methodology used to explore the design space of the proposed circuit family.

Abstrak :
This book presents a novel logarithmic conversion architecture based on cross-coupled inverter. An overview of the current state of the art of logarithmic converters is given where most conventional logarithmic analog-to-digital converter architectures are derived or adapted from linear analog-to-digital converter architectures, implying the use of analog building blocks such as amplifiers. The conversion architecture proposed in this book differs from the conventional logarithmic architectures. Future possible studies on integrating calibration in the voltage to time conversion element and work on an improved conversion architecture derived from the architecture are also presented in this book.