Studi Eksperimen Variasi Laju Pendinginan Kondensor pada Mesin Pendingin Difusi Absorpsi R22-DMF

Teknologi pendinginan lama yang mulai digunakan salah satunya adalah mesin pendingin Difusi Absorpsi COP dari mesin pendingin difusi absorpsi banyak dipengaruhi dari  desain generator. Pada penelitian ini eksperimen dilakukan dengan mendesain ulang generator pada mesin pendingin difusi absorpsi yang menggunakan pasangan refrigeran R22-DMF serta penambahan fan di kondensor. Metode dalam penelitian ini adalah pengambilan data dilakukan dengan empat variasi laju pendinginan pada kondensor. Hasil yang diperoleh dari pengujian untuk variasi laju pendinginan dari 0,711 m/s hingga 2,291 m/s yaitu semakin tinggi laju pendinginan maka semakin baik performa pada sistem. Kapasitas pendinginan optimal ialah 143 W, COP tertinggi 0,96, laju alir massa refrigeran terbesar ialah 0,72 gram/s, dan circulation ratio terendah yaitu 2,11

XVI Agricultural Science Congress 2023: Transformation of Agri-Food Systems for Achieving Sustainable Development Goals

The XVI Agricultural Science Congress being jointly organized by the National Academy of Agricultural Sciences (NAAS) and the Indian Council of Agricultural Research (ICAR) during 10-13 October 2023, at hotel Le Meridien, Kochi, is a mega event echoing the theme “Transformation of Agri-Food Systems for achieving Sustainable Development Goals”. ICAR-Central Marine Fisheries Research Institute takes great pride in hosting the XVI ASC, which will be the perfect point of convergence of academicians, researchers, students, farmers, fishers, traders, entrepreneurs, and other stakeholders involved in agri-production systems that ensure food and nutritional security for a burgeoning population. With impeding challenges like growing urbanization, increasing unemployment, growing population, increasing food demands, degradation of natural resources through human interference, climate change impacts and natural calamities, the challenges ahead for India to achieve the Sustainable Development Goals (SDGs) set out by the United Nations are many. The XVI ASC will provide an interface for dissemination of useful information across all sectors of stakeholders invested in developing India’s agri-food systems, not only to meet the SDGs, but also to ensure a stable structure on par with agri-food systems around the world. It is an honour to present this Book of Abstracts which is a compilation of a total of 668 abstracts that convey the results of R&D programs being done in India. The abstracts have been categorized under 10 major Themes – 1. Ensuring Food & Nutritional Security: Production, Consumption and Value addition; 2. Climate Action for Sustainable Agri-Food Systems; 3. Frontier Science and emerging Genetic Technologies: Genome, Breeding, Gene Editing; 4. Livestock-based Transformation of Food Systems; 5. Horticulture-based Transformation of Food Systems; 6. Aquaculture & Fisheries-based Transformation of Food Systems; 7. Nature-based Solutions for Sustainable AgriFood Systems; 8. Next Generation Technologies: Digital Agriculture, Precision Farming and AI-based Systems; 9. Policies and Institutions for Transforming Agri-Food Systems; 10. International Partnership for Research, Education and Development. This Book of Abstracts sets the stage for the mega event itself, which will see a flow of knowledge emanating from a zeal to transform and push India’s Agri-Food Systems to perform par excellence and achieve not only the SDGs of the UN but also to rise as a world leader in the sector. I thank and congratulate all the participants who have submitted abstracts for this mega event, and I also applaud the team that has strived hard to publish this Book of Abstracts ahead of the event. I wish all the delegates and participants a very vibrant and memorable time at the XVI ASC

Studi Eksperimen Variasi Laju Pendinginan Kondensor pada Mesin Pendingin Difusi Absorpsi R22-DMF

Teknologi pendinginan lama yang mulai digunakan salah satunya adalah mesin pendingin Difusi Absorpsi COP dari mesin pendingin difusi absorpsi banyak dipengaruhi dari  desain generator. Pada penelitian ini eksperimen dilakukan dengan mendesain ulang generator pada mesin pendingin difusi absorpsi yang menggunakan pasangan refrigeran R22-DMF serta penambahan fan di kondensor. Metode dalam penelitian ini adalah pengambilan data dilakukan dengan empat variasi laju pendinginan pada kondensor. Hasil yang diperoleh dari pengujian untuk variasi laju pendinginan dari 0,711 m/s hingga 2,291 m/s yaitu semakin tinggi laju pendinginan maka semakin baik performa pada sistem. Kapasitas pendinginan optimal ialah 143 W, COP tertinggi 0,96, laju alir massa refrigeran terbesar ialah 0,72 gram/s, dan circulation ratio terendah yaitu 2,11

An Induction Motor Drive Scheme Generating Twenty-Four Sided Voltage Space Vector Structure with Linear Modulation Range Near to Base Speed

In this paper, a drive scheme generating 24-sided polygonal voltage space vector structure using an inverter topology with single DC source is proposed. A 24-sided structure eliminates dominant low-order phase voltage harmonics including and up to seventeenth and nineteenth orders throughout the speed range including step operation. The power circuit has a two-level inverter and two low voltage cascaded H-bridge cells fed with capacitors. The linear modulation range is extended to 99.42% of the base speed with such a polygonal structure. A reduced PWM switching sequence resulting in minimum pole voltage transitions for the two-level inverter and shifting relatively higher frequency operation to low voltage H-Bridge inverters feature the drive scheme for controlling losses

A 24-Sided Voltage Space Vector Based IM Drive with Low-Order Harmonic Elimination for the Full Speed Range

This paper proposes an inverter topology to generate a 24-sided polygonal voltage space vector structure for variable speed drives using a single dc source. The topology consists of a two-level inverter cascaded with two low-voltage floating capacitor-fed H-bridge cells. The 24-sided structure eliminates harmonics up to and including seventeenth and nineteenth orders from phase voltage output resulting in a smooth torque profile over the entire speed range. This structure also enhances the linear modulation range to 99.42% of the base speed. A reduced switching sequence based pulse width modulation technique achieves minimum pole voltage transitions for the two-level inverter, thereby controlling switching losses. The lower order harmonics are eliminated by switching action of low-voltage H-bridge cells. Experimental results, simulation studies on inverter losses, and harmonic performance validate the effectiveness of proposed drive scheme

Multilevel 24-Sided Polygonal Voltage-Space-Vector Structure Generation for an IM Drive Using a Single DC Source

Conventional two-level as well as multilevel voltage-source-inverter topologies with a hexagonal voltage-space vector structure generate low-order harmonics in the machine terminal voltages when operated beyond the linear modulation range in variable speed drive application. Progressing from hexagonal to a higher sided polygonal voltage-space-vector structure (VSVS) suppresses significant low-order harmonics throughout the modulation range. In addition, the linear modulation range will also be enhanced very near to the base speed. In this paper, for the first time, the generation of a multilevel 24-sided VSVS using a single dc source for induction-motor drives is proposed. A cascaded topology with a dc-source-fed flying-capacitor inverter and two low-voltage capacitor-fed H-bridge cells forms the power circuit. The features and advantages of the proposed scheme are validated through experimental results and discussions