The photovoltaic generation system (PGS) is considered a potential renewable energy harvesting system. However, the low conversion efficiency of PGS and maximum power point tracking (MPPT) technique are the main challenges that must be solved. In addition, the switching frequency of the converters employed also affects the MPPT system performance. A high gain voltage dc-dc converter is proposed to replace conventional power converter and Fuzzy Logic Control (FLC) is applied in the MPPT for optimizing solar energy harvesting system. Nevertheless, evaluation of suitable Fuzzy membership function is needed for optimal MPPT technique of photovoltaic system. In this paper, FLC of MPPT for photovoltaic application system was built using various membership functions in Matlab/Simulink environment. The switching frequency of the high gain voltage dc-dc converter is varied to test the robustness of the performance of each FLC membership function. The results showed that the FLC-based MPPT technique for high gain voltage dc-dc converter with GBell membership function type has capability to track the maximum power point (MPP) accurately and to achieve optimum power conversion. Furthermore, GBell membership showed having stable and consistent performance at various switching frequencies.

Penelitian ini bertujuan mengkaji tepung bonggol pisang sebagai pengganti molases terhadap fermentabilitas pakan komplit berbasis jerami padi amoniasi secara in vitro. Penelitian menggunakan rancangan Uji T (T-Test) Independent Sample pada taraf signifikasi 5% dengan 2 perlakuan dan 6 ulangan. Data yang diperoleh dianalisis menggunakan SPSS. Perlakuan yang digunakan pada penelitian ini yaitu (T1: pakan komplit 98% + molases 2%) dan (T2: pakan komplit 97,37% + tepung bonggol pisang 2,65%). Hasil penelitian menunjukkan bahwa penggantian molases dengan bonggol pisang pada pakan komplit berbasis jerami padi amoniasi secara in vitro tidak memberikan pengaruh yang berbeda (p>0,05) terhadap rerata produksi NH 3 T1 (2,39 mM) dan T2 (2,31 mM), konsentrasi VFA total T1 (58,33 mM) dan T2 (63,33 mM), asam asetat T1 (71,80%) dan T2 (72,22%), asam propionat T1 (20,67%) dan T2 (21,84%), asam butirat T1 (7,26%) dan T2 (6,27%), rasio C 2 /C 3 pada T1 (3,45) dan T2 (3,32), kecernaan bahan kering T1 (73,34%) dan T2 (72,51%) dan kecernaan bahan organik T1 (80,80%) T2 dan (77,74%). Berdasarkan hasil penelitian dapat disimpulkan bahwa bonggol pisang dapat menggantikan molases sebagai sumber RAC pada pakan komplit berbasis jerami padi amoniasi.

This researchwasconducted at Feed and Nutrition Laboratory, Faculty of Animal and Agriculture, Diponegoro University, Semarang from October to November 2016. The study aims to examine the total protein production and protein digestibility of Moringa leaf in vitro. The study was done in three stages: preparation, in vitro test and analysis. The material used of rumen goat crossbreed etawa (PE), moringa leaf and leucaena leaf as a comparison T-test. Productiontotal protein was analyzed by Tilley and Terry method 1, while protein digestibility was analyzed using Tilley and Terry 2 method.Protein analysis using Kjeldahl method 1883 according to (AOAC, 2005).The results showed that total production of total Moringa leaf protein was not different (P>0.05) compared with lamtoro leaf (377,60 mg/g vs 478,92 mg/g).The digestibility of Moringa leaf protein was significantly (P<0.05) higher compared with lamtoro leaf (64.29% vs 50.74%). The conclusion of this research is that Moringa leaf has good quality as protein source of ruminant livestock because it possess high protein digestibility compared with leaf leucaena.Key words: Kelor, in vitro, total protein production, protein. ABSTRAKPenelitian dilaksanakan di Laboratorium Ilmu Nutrisi dan Pakan, Fakultas Peternakan dan Pertanian, Universitas Diponegoro, Semarang bulan Oktober-November 2016. Penelitian bertujuan untuk mengkaji produksi protein total dan kecernaan protein dari daun kelor secara in vitro. Penelitian dilakukan dalam tiga tahap yaitu persiapan, uji in vitro dan analisis. Materi yang digunakan yaitu cairan rumen kambing peranakan etawa (PE), daun kelor dan daun lamtoro yang digunakan sebagai pembanding uji T-test. Produksi protein total di analisis dengan metode Tilley dan Terry tahap 1, sedangkan kecernaan protein di analisis menggunakan metode Tilley dan Terry 2 tahap. Analisis protein menggunakan metode Kjeldhal 1883 menurut (AOAC, 2005). Hasil penelitian menunjukan bahwa jumlah produksi protein total daun kelor tidak berbeda (p≥0,05) dibanding an dengan daun lamtoro (377,60 mg/g vs 478,92 mg/g). ecernaan protein daun elor nyata lebih tinggi (p≤0,05) dibanding an dengan daun lamtoro (64,29% vs 50,74%). Simpulan dari hasil penelitian adalah daun kelor mempunyai kualitas yang baik dibandingkan daun lamtoro karena memiliki kecernaan yang tinggi pasca rumen.Kata kunci: Kelor, in vitro, produksi protein total, protein. PENDAHULUANTernak ruminansia merupakan ternak yang memiliki saluran pencernaan yang khas, karena memiliki lambung majemuk yaitu rumen, retikulum, omasum dan abomasum. Ternak ruminansia mampu mencerna pakan yang memiliki kualitas rendah (kandungan serat yang tinggi) karena di dalam rumen ternak ruminansia terdapat mikroorganisme yang berfungsi memfermentasi serat pakan. Persyaratan sumber protein untuk ternak ruminansia antara lain: mampu menyediakan N bagi pertumbuhan mikrobia, tahan degradasi atau mampu menyediakan UDP yang tinggi, dan memiliki nilai hayati tinggi.Daun kelor memiliki kandungan nutrisi yang cukup baik diantaranya protein k...

Solar harvesting system with photovoltaic (PV) is one of the most desirable renewable energy sources because of its prominent advantages. However, low efficiency due to fluctuating output power is a major problem for PV systems. A technique used to maximize power extraction known as maximum power point tracking (MPPT) has been proposed by various literature to deal with this problem. One of the most widely developed MPPT methods due to its ease of implementation is perturb and observe (P&amp;O). Since the initial discovery of the principle, the P&amp;O method has been extensively modified including the fixed step-size: step-size variables, partial shading, threshold module current, three-point-comparison, maximization of dynamic performance, minimization of dynamic performance, bandwidth of 𝑃 − 𝑉 curve, decoupling, observation of 𝑑𝑉, 𝑑𝐼, and 𝑑𝑃, datasheet parameters, curve fitting, voltage hold P&amp;O, and observation of 𝑑𝑉 and 𝑑𝑃. This paper presents the development of the P&amp;O method from the initial principle to the end as a reference source for readers. The hope is that a new easy and robust P&amp;O method as a complement to the implementation of the MPPT technique is developed in the solar harvesting system.

<p>Harvesting solar energy as a renewable energy source has received significant attention through serious studies that could be applied massively. However, the nonlinear nature of photovoltaic (PV) concerning the surrounding environment, especially irradiation and temperature, affects the resulting output. Therefore, the correlation between environmental parameters and PV's energy needs to be studied. This paper presents a design for measuring solar PV parameters monitored on a laboratory scale. The monitoring is based on internet of things (IoT) technology analyzed in realtime. The system was tested in various weather conditions for 18 hours. The results obtained indicate that the output voltage was influenced by the lighting factor of the PV and the surrounding temperature.</p>

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Adjustable Speed Drive (ASD) fed Matrix Converter is an interesting topic and is widely discussed in several articles. ASD provides many advantages, especially in the industrial sector because it increases work efficiency so as to reduce production costs. The induction machines construction is sturdy and its relatively inexpensive maintenance makes it more desirable in industrial process applications. Whereas the Matrix Converter (MC) construction without dc-link capacitors makes it more compact compared to conventional converters. This article discussed the ASD control modulation technique by using MC on a threephase induction motor.

Photovoltaic (PV) system is an electrical generator that has been widely used. Ease of implementation, supported by a large number of potentials and needs of Green Energy, has become a factor in the increasing number and quickly applied to PV arrays. However, PV arrays have constrained related to generator conversion efficiency and the amount of power produced due to inconstant irradiation and temperature. This problem can be solved by a Maximum Power Point Tracking (MPPT) approach. This article discusses the MPPT technique with High Gain DC-DC Boost Converter using the Perturb and Observe (P&O) algorithm. The same P&O algorithm is also tested in the conventional converter to show performance and superiority of each converter. The results obtained show the advantages and disadvantages of each converter used in MPPT by P&O algorithm.