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"This book describes an original improvement in power quality of photovoltaic generation systems obtained by the use of a multilevel inverter implemented with level doubling network (LDN). Modulation principles and harmonic analysis of output voltages are proposed and introduced in detail for both single and three-phase LDN configurations. The analysis is then extended to dc-link current and voltage, with emphasis to low-frequency harmonics and switching frequency ripple. This work represents the first comprehensive implementation of maximum power point tracking (MPPT) schemes using the ripple correlation control (RCC) algorithm in the presence of multiple ripple harmonics, such as in the case of multi­level inverters. Numerical simulations and experimental tests are carefully reported here, together with practical insights into the design of dc-link capacitors."

"This book discusses topics related to power electronics, especially electromagnetic transient analysis and control of high-power electronics conversion. It focuses on the re-evaluation of power electronics, transient analysis and modeling, device-based system-safe operating area, and energy balance-based control methods, and presenting, for the first time, numerous experimental results for the transient process of various real-world converters."

"Buruknya pencemaran lingkungan sebagai dampak pemanfaatan energi fosil, membuat dunia bertransformasi pada pemanfaatan energi ramah lingkungan yaitu energi terbarukan, khususnya energi surya photovoltaic (PV). Bagian terpenting dari sistem PV adalah performansinya dalam menghasilkan energi. IEC 61724 menetapkan parameter performansi sistem PV antara lain produksi energi, array yield, final yield, reference yield, performance ratio, capacity factor, efisiensi energi dan losses. Pada penelitian ini, kinerja sistem PV atap berkapasitas 10,6 kWp di Gedung Energi, Puspiptek dievaluasi untuk mengetahui nilai parameter performansinya menurut IEC 61724 sebagai tolok ukur kinerja sistem PV. Evaluasi dilakukan berdasarkan pemantauan selama delapan bulan dengan data yang diperolah dari SCADA pada sistem PV. Analisis produksi energi menunjukkan bahwa sistem PV mampu menghasilkan energi AC sebesar 36,10 kWh per hari. Analisis array yield, reference yield dan final yield memperlihatkan bahwa sistem PV mampu beroperasi secara penuh rata-rata selama 3,51 jam per hari dengan potensi penyinaran matahari rata-rata selama 4,14 jam per hari dimana produksi energi AC rata-rata selama 3,41 jam per hari. Analisis performance ratio menunjukkan bahwa sistem PV mampu mengubah 82,67% energi matahari yang diterimanya. Analisis capacity factor memberikan hasil 14,19% yang berarti sistem PV beroperasi secara penuh selama 34,62 hari selama periode pemantauan. Analisis efisiensi menunjukkan bahwa array PV bekerja dengan efisiensi 15,31% dan inverter bekerja dengan efisiensi 96,70%. Dari nilai-nilai efisiensi tersebut, dihasilkan bahwa sistem PV secara keseluruhan bekerja dengan efisiensi sistem 14,80%. Hasil analisis array capture losses menunjukkan bahwa pada array PV terjadi losses rata-rata sebesar 0,63 kWh/kWp per hari dan analisis system losses menunjukkan bahwa losses pada inverter PV rata-rata sebesar 0,1 kWh/kWp per hari. Pada akhir penelitian ini dilakukan simulasi menggunakan aplikasi online PVGIS untuk untuk mendapatkan data jumlah produksi energi. Hasil simulasi tersebut dibandingkan dengan hasil perhitungan yang dilakukan sebelumnya. Setelah dilakukan perbandingan, disimpulkan bahwa hasil perhitungan produksi energi dan radiasi matahari global secara umum mendekati hasil simulasi produksi energi dan radiasi matahari global kecuali pada bulan Januari dan Februari 2020. Hasil perhitungan dan simulasi pada bulan-bulan tersebut memilki selisih cukup tinggi. Berdasarkan evaluasi kinerja secara keseluruhan, sistem PV 10,6 kWp di Gedung Energi Puspiptek memiliki kinerja yang baik.

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Poor environmental pollution as a result of the use of fossil energy, making the world transform to use renewable energy that is more environmentally friendly, especially photovoltaic (PV) solar energy. The most important issue of a PV system is their performance in producing energy. IEC 61724 establishes the performance parameters of a PV system including energy production, array yields, final yields, reference yields, performance ratios, capacity factors, energy efficiency and losses. In this study, the performance of the 10,6 kWp PV rooftop system in the Energy Building, Puspiptek was evaluated to determine the value of its performance parameters according to IEC 61724 as a benchmark for PV system performance. The evaluation was carried out based on eight months monitored period with the data obtained from the SCADA in the PV system. Analysis of energy production shows that the PV system is able to produce AC energy of 36.10 kWh per day. Analysis of array yields, reference yields, and final yields shows that the PV system is capable to operate for 3.51 hours per day on average with an average solar irradiation potential of 4.14 hours per day and the AC energy production is 3.41 hours per day on average. Performance ratio analysis shows that the PV system is able to convert 82.67% of the concerning solar energy. Capacity factor analysis gives a result of 14.19% which means the PV system has been operated for 34.62 days at its full nominal power during the monitoring period. Analysis of efficiency shows that the PV array works with an efficiency of 15.31% and the inverter works with an efficiency of 96.70%. Based on these efficiency values, the whole PV system works with a system efficiency of 14.80%. The analysis of array capture losses shows that losses on the PV arrays 0.63 kWh/kWp per day on average and system losses analysis shows that losses on PV inverters 0.1 kWh/kWp per day on average. At the end of this study, a simulation by an online PVGIS application is used to obtain data on energy production. The results of the simulation are compared with the results of previous calculations. From the comparison, it was concluded that the results of the calculations of energy production and global solar radiation approached the results of simulations of energy production and global solar radiation except in January and February 2020. The calculation and simulation results of these months show greater differences. Based on an overall performance evaluation, the 10,6 kWp PV system at the Puspiptek Energy Building has good performance."

"Conservation Voltage Reduction (CVR) adalah metode untuk mengurangi konsumsi daya dan permintaan puncak. Ini bukan studi baru karena sudah banyak implementasi dan penelitian tentang CVR sebelumnya. CVR menyiratkan bahwa dengan mengurangi tegangan suatu perangkat atau sistem, daya yang dikonsumsi juga akan berkurang. Hal ini dapat dibuktikan dengan menggunakan persamaan daya listrik yang menyatakan bahwa daya sebanding dengan tegangan.Sistem energi terbarukan sedang meningkat karena semakin murah dan lebih efisien. Daya yang dikeluarkan oleh sistem energi terbarukan tergantung pada faktor sumbernya, apakah itu radiasi atau kecepatan angin. CVR memungkinkan pengurangan konsumsi daya beban. Ini membantu mengurangi beban sistem karena mereka tidak harus menghasilkan lebih banyak daya daripada kebutuhan beban.Sistem PV dan turbin angin mikro memiliki keluaran yang berbeda, tetapi keduanya perlu memasok beban yang sama dalam jaringan mikro. Kedua sistem pada akhirnya diubah menjadi daya AC untuk digunakan beban. Inverter digunakan di kedua sistem untuk membantu konversi. Inverter umum memiliki fluktuasi tegangan antara -20% dan +10% dari tegangan nominalnya. Sebuah sistem kontrol digunakan untuk mengatur tegangan keluaran inverter dan memastikan tidak mencapai kisaran tegangan maksimum. Sistem kontrol akan memungkinkan output inverter diatur lebih dekat ke tegangan nominal dan dengan demikian mengurangi tegangan berlebih.Sistem energi terbarukan menghasilkan tegangan yang lebih rendah setelah sistem kontrol diterapkan untuk mengatur keluaran inverter. CVR telah dicapai dalam sistem ini. Sistem telah mengurangi konsumsi daya dan dengan demikian menurunkan beban sistem. Sistem tidak menghemat energi dengan menerapkan CVR. Perangkat yang bergantung pada voltase masih akan membutuhkan lebih banyak daya jika voltase perangkat dinaikkan. Sistem PV dan turbin angin mikro dengan CVR memungkinkan beban mendapatkan input tegangan yang lebih sehat sekaligus mengurangi konsumsi daya.

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Conservation voltage reduction (CVR) is a method to reduce power consumption and peak demand. It is not a new study as there have been plenty of implementations and research regarding CVR for a long time. CVR implies that by reducing the voltage of a device or system, the power consumed will also be reduced. This can be proven using the electrical power equation where it states that power is proportional to voltage. Renewable energy systems are on the rise as they are getting cheaper and more efficient. The power outputted by a renewable energy system depends on their source factor whether it is irradiance or wind speed. Conservation voltage reduction allows the reduction of power consumption of the load. This helps decrease the burden of the system as they do not have to generate more power than the load needs.

PV systems and micro wind turbines have different outputs, but both need to supply the same load in a micro-grid. Both systems are eventually converted to AC power for the load to use. An inverter is used in both systems to help with the conversion. A common inverter has a voltage fluctuation between -20% and +10% of its nominal voltage. A control system is used to regulate the inverter’s output voltage and make sure it does not reach the maximum voltage range. The control system will allow the output of the inverter to be regulated much closer to the nominal voltage and thus decreasing excess voltage. The renewable energy system outputs a lower voltage after a control system has been applied to regulate the output of the inverter. Conservation voltage reduction has been achieved in this system. The system has reduced power consumption and thus lowering the burden of the system. The system does not save energy by implementing conservation voltage reduction. A voltage-dependent device will still demand more power if the voltage of the device is increased. The PV and micro wind turbine system with CVR allows the load to benefit healthier voltage input while having reduced power consumption."

"This book reports on a comprehensive study addressing the dynamic responses of hydropower plants under diverse conditions and disturbances, and analyzes their stability and oscillations. Multiple models based on eight existing hydropower plants in Sweden and China were developed and used for simulations and theoretical analysis with various degrees of complexity and for different purposes, and compared with on-site measurements for validations. The book offers important insights into the understanding of the hydraulic, mechanical and electrical coupling mechanisms, up to market conditions and incentives. It recommends control strategies for a more stable and efficient operation of hydropower plants."

"Control of solar energy systems details the main solar energy systems, problems involved with their control, and how control systems can help in increasing their efficiency. Thermal energy systems are explored in depth, as are photovoltaic generation and other solar energy applications such as solar furnaces and solar refrigeration systems. This second and updated edition of advanced control of solar plants includes new material on, solar towers and solar tracking, heliostat calibration, characterization and offset correction, solar radiation, estimation, prediction, and computation, and integrated control of solar plants. This new edition contains worked examples in the text as well as proposed exercises and simulation models."

"Dengan semakin berkembangnya kendaraan listrik maka pengembangan pada teknologi penghematan energi pun mengalami kemajuan. Pada proses pengereman motor biasanya akan menimbulkan energi kinetik yang berlebihan, kelebihan energi kinetik ini biasanya akan diubah menjadi energi listrik yaitu berupa arus balik. Pada monorail ataupun kereta rel listrik arus balik ini akan masuk ke dalan jaringan DC link, namun apabila arus balik ini terlalu besar dapat menimbulkan over voltage yang dapat merusak komponen-komponen pada inverter. Metode pengereman regeneratif dikembangkan untuk mengatasi permasalahan yang ditimbulkan karena arus balik ini, untuk mencegah timbulnya over voltage maka tegangan pada DC link dibatasi sehingga arus balik yang terjadi tidak begitu besar dan tegangan pada DC link dapat dijaga agar sesuai dengan acuannya. Dengan menggunakan metode ini arus dapat dibatasi namun sebagai kompensasinya diperlukan bantuan torsi mekanik agar pengereman dapat sesuai yang diinginkan. Penggunaan bidirectional converter sudah banyak dikembangkan agar dapat menurunkan tegangan pada DC Link tanpa memerlukan bantuan torsi mekanik dari luar. Dengan menggunakan voltage control rangkaian ini dapat dikendalikan untuk dapat menyimpan energi berlebihan yang timbul pada proses pengereman kemudian dapat memberikan daya pada saat proses motoring.

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With the recent revival of the electrical vehichle much advancement in power management has been made. Braking process cause surplus of kinetic energy in motor. These kinetic energy are converted to electrical energy in form of opposite current In electric vehicle such as monorail and electrical train this opposite current will be enter the DC link circuit, if the current is too large it can cause overvoltage that can damage components in inverter.

Regenerative braking method is developed in order to solve this problem, to prevent the over voltage the DC link voltage must be limit so the opposite current is not to high. With this method the current will be limit but as the compensation the braking systems need mechanical torque.

This bidirectional converter has been develop in order to reduce DC link voltage without need mechanical torque. These circuit can be controlled to save the kinetic energy that comes from the braking process and these energy can be used later for motoring condition."

"This book describes and assesses energy technologies, markets and future strategies, focusing on their capacity to produce, exchange, and use energy vectors. Special attention is given to the renewable energy resources available in different areas of the world and made exploitable by the integration of energy vectors in the global energy system. Clear definitions of energy vectors and energy systems are used as the basis for a complete explanation and assessment of up-to-date, available technologies for energy resources, transport and storage systems, conversion and use. The energy vectors scheme allows the potential realization of a worldwide sustainable energy system to fulfill global development expectations by minimizing both the impact on the environment, and the international political frictions for access to limited and concentrated resources."

"Pemerintah Indonesia mencanangkan program penggantian pembangkit listrik lama berbahan bakar fosil dengan pembangkit listrik Energi Terbarukan. Meskipun irradiasi matahari di negara ini baik, pengembangan pembangkit listrik tenaga surya fotovoltaik (PLTS) masih menghadapi hambatan-hambatan. Dalam penelitian ini dilakukan analisa tekno-ekonomi untuk mendapatkan desain PLTS yang optimal menggunakan HOMER Pro dan analisa kelayakan proyek melalui metode Discounted Cash Flow. Hasilnya, desain yang paling optimal adalah sistem tekoneksi jaringan dengan inverter 1 string sebesar 8MW serta opsi penggunaan baterai dan sistem penyimpan energi (BESS) sebesar 22,5 MWh 600V. PLTS tanpa BESS mendapatkan WACC sebesar 8,52%, PI sebesar 1,39, dan IRR sebesar 21,30%. Sedangkan PLTS dengan BESS memerlukan intervensi untuk meningkatkan keekonomian. Intervensi yang diuji dalam penelitian ini adalah pajak karbon, skema lelang kompetitif, pembangunan jalur transmisi, dan penyesuaian tarif. Kombinasi penerapan pajak karbon sebesar USD 3,6 sen/ton CO2e dan penyesuaian tarif minimum +36,15%, menghasilkan keekonomian yang lebih baik dengan IRR sebesar 14,74%. Skema lelang kompetitif dapat meningkatkan kelayakan skenario “dengan BESS” dengan WACC sebesar 1,88%, dan IRR sebesar 5,89%. Meskipun pengembangan PLTS tanpa BESS dapat dilakukan, risiko yang menyebabkan peningkatan modal harus dihindari. Sementara PLTS dengan BESS harus diintervensi untuk menurunkan biaya modal.

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The Government of Indonesian launched programs of old fossil fuel-based power plants replacement with Renewable Energy power plant. Despite abundant solar irradiance in the country, solar photovoltaic (PV) power plant (Solar PV) development is facing interfering barriers. This research carried out techno-economic analysis of Solar PV design to obtain the most optimum design by using HOMER Pro and exercise project feasibility through Discounted Cash Flow method. The result shows that the most optimum technical design is grid-connected equipped with 1 string inverter of 8MW and optional Battery and Energy Storage System (BESS) of 22.5 MWh 600V. Without BESS Solar PV earned WACC of 8.52%, PI of 1.39, and IRR of 21.30%. While the development of solar PV power plant with BESS requires several interventions to enhance the economic. Some tested intervention i.e. carbon tax, competitive auction scheme, transmission line development, and tariff adjustment. A combination of Carbon Tax implementation of cents USD 3,6/ton CO2e and tariffs adjustment of minimum +36,15%, results in higher economic with IRR of 14.74%. A competitive auction scheme could enhance the feasibility level of “with BESS” scenario with WACC of 1.88%, and IRR of 5.89%. Despite of solar PV power plant without BESS development is feasible, some risks which lead to capital increasement should be avoided. While solar PV power plant with BESS development should be intervened by some measures to lower the capital cost."

"ABSTRAKEfisiensi yang tinggi merupakan persyaratan yang vital dalam merancangsebuah pembangkit. Salah satu alternatif yang memenuhi persyaratan tersebutadalah DFIG . Namun DFIG tersebut perlu dikendalikan agar bisa bekerja sesuaidengan aplikasinya.Skripsi ini membahas metoda pengendalian tegangan dan frekuensikeluaran daripada DFIG . Metoda pengendalian yang digunakan merupakanpengendalian skalar. Dimana frekuensi dan tegangan keluaran dikendalikan secaraterpisah dan keluaran sinyal kendalinya akan menyesuaikan dengan putaran turbingenerator dan setpoin yang diinginkan.

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ABSTRACTHigh efficiency is the most vital aspect to design a power distributionsystem . One of the alternative to meets the requirement is DFIG. But, we need tocontrol the DFIG to meet the desired output.This paper introduce a method to control the voltage and frequency outputof the DFIG . The method is called scalar control. Where the voltage andfrequency are controlled separately . The control signal will adapt to the turbinespeed from the generator and desired setpoint."