The rapid improvement of lithium-ion rechargeable battery (LIRB) has given a powerful impetus to the development of environmentally friendly, powerful and universal for use on ships and underwater vehicles. The practice of building electric ships for many years has confirmed the effectiveness of electric propulsion for many types of vessels. Organically, electric propulsion fits into icebreakers and those vessels whose operation is associated with increased maneuvering modes and variable loads on propellers. LIRB has been actively used on ferries operating in a wide range of outdoor temperatures. On diesel-electric submarines (DES), the use of rechargeable batteries is traditional and is the main source of electricity. The subsequent development of new sources of electricity, the improvement of power semiconductor devices and microelectronics has led to the successful implementation of ideas for the construction of fully electric offshore facilities.
The main voltage parameters of marine electrical propulsion installations, at various load capacities, with further stress assessment are discussed in the article. By considering voltage options, it was revealed that an increase in inductive resistance makes it possible to manufacture a machine with high power, but the quality of electrical energy in transient modes is deteriorated. During starts, reversals, resets and load surges of powerful consumers, large voltage dips will occur on the generator. To solve the problem, including determination of optimal parameters of the generator, based on the multifactorial nature of the task of creating an electric machine for a specific purpose, an analysis of all the necessary parameters was carried out. The main dimensions of the machine depend on its full power, angular speed and electromagnetic loads. The article presents technical solutions considered using the example of a modern multipurpose icebreaker-supply “Vitus Bering”. Also, as an example, an icebreaker of the Taimyr type with a limited draft is considered, for the first time in modern practice, an alternating-changing current EDMS is used. From the experience of operating the icebreakers “Taimyr” and “Vaigach”, the transition to high voltage did not lead to a complication and increase in the complexity of the maintenance of the MPM, although it required strict compliance with safety regulations during the work. During the operation of icebreakers with MPM 6.3 kV, not a single case of single-phase short circuit or electrical injury has been recorded.
Alkaline transesterification of sunflower oil by n-butanol and ethanol on alkoxide-containing dried solutions of potassium hydroxide has been carried out. Complex character of spontaneous dividing of butanolysis products, accompanying with formation of three different species of glycerol layers, was observed. One of the later was found to be high-alkaline pure glycerol. Bench motor testing of biodiesel/diesel blends demonstrated slightly better power performance of butyl esters comparing with ethyl esters and regular decrease of harmful emissions (CO2, CO, NOx, CH) while increasing biodiesel fraction in mixture.
Внастоящее время укрепляется тенденция к созданию полностью электрических автономных морских объектов, а целесообразность проектирования кораблей и судов с полным электродвижением уже практически не вызывает сомнений. Понятие “полностью электрическое судно или корабль” не имеет строгого толкования и авторами отождествляется с наличием трёх основных составляющих: всережимной системы электродвижения, мощного основного источника электроэнергии и высоконадёжного, высокоэффективного вспомогательного электропривода различных электромеханизмов с глубоким плавным регулированием во всём диапазоне и коротким реверсом электродвигателей для замены механических, гидравлических, пневматических приводов на электрические.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.