42 research outputs found
Applications of Mathematical Models in Engineering
The most influential research topic in the twenty-first century seems to be mathematics, as it generates innovation in a wide range of research fields. It supports all engineering fields, but also areas such as medicine, healthcare, business, etc. Therefore, the intention of this Special Issue is to deal with mathematical works related to engineering and multidisciplinary problems. Modern developments in theoretical and applied science have widely depended our knowledge of the derivatives and integrals of the fractional order appearing in engineering practices. Therefore, one goal of this Special Issue is to focus on recent achievements and future challenges in the theory and applications of fractional calculus in engineering sciences. The special issue included some original research articles that address significant issues and contribute towards the development of new concepts, methodologies, applications, trends and knowledge in mathematics. Potential topics include, but are not limited to, the following: Fractional mathematical models; Computational methods for the fractional PDEs in engineering; New mathematical approaches, innovations and challenges in biotechnologies and biomedicine; Applied mathematics; Engineering research based on advanced mathematical tools
Contributions to impedance shaping control techniques for power electronic converters
El conformado de la impedancia o admitancia mediante control para convertidores electrónicos de potencia permite alcanzar entre otros objetivos: mejora de la robustez de los controles diseñados, amortiguación de la dinámica de la tensión en caso de cambios de carga, y optimización del filtro de red y del controlador en un solo paso (co-diseño). La conformación de la impedancia debe ir siempre acompañada de un buen seguimiento de referencias. Por tanto, la idea principal es diseñar controladores con una estructura sencilla que equilibren la consecución de los objetivos marcados en cada caso. Este diseño se realiza mediante técnicas modernas, cuya resolución (síntesis del controlador) requiere de herramientas de optimización. La principal ventaja de estas técnicas sobre las clásicas, es decir, las basadas en soluciones algebraicas, es su capacidad para tratar problemas de control complejos (plantas de alto orden y/o varios objetivos) de una forma considerablemente sistemática. El primer problema de control por conformación de la impedancia consiste en reducir el sobreimpulso de tensión ante cambios de carga y minimizar el tamaño de los componentes del filtro pasivo en los convertidores DC-DC. Posteriormente, se diseñan controladores de corriente y tensión para un inversor DC-AC trifásico que logren una estabilidad robusta del sistema para una amplia variedad de filtros. La condición de estabilidad robusta menos conservadora, siendo la impedancia de la red la principal fuente de incertidumbre, es el índice de pasividad. En el caso de los controladores de corriente, el impacto de los lazos superiores en la estabilidad basada en la impedancia también se analiza mediante un índice adicional: máximo valor singular. Cada uno de los índices se aplica a un rango de frecuencias determinado. Finalmente, estas condiciones se incluyen en el diseño en un solo paso del controlador de un convertidor back-to-back utilizado para operar generadores de inducción doblemente alimentados (aerogeneradores tipo 3) presentes en algunos parques eólicos. Esta solución evita los problemas de oscilación subsíncrona, derivados de las líneas de transmisión con condensadores de compensación en serie, a los que se enfrentan estos parques eólicos. Los resultados de simulación y experimentales demuestran la eficacia y versatilidad de la propuesta.Impedance or admittance shaping by control for power electronic converters allows to
achieve among other objectives: robustness enhancement of the designed controls, damped
voltage dynamics in case of load changes, and grid filter and controller optimization in
a single step (co-design). Impedance shaping must always be accompanied by a correct
reference tracking performance. Therefore, the main idea is to design controllers with a
simple structure that balance the achievement of the objectives set in each case. This
design is carried out using modern techniques, whose resolution (controller synthesis)
requires optimization tools. The main advantage of these techniques over the classical
ones, i.e. those based on algebraic solutions, is their ability to deal with complex control
problems (high order plants and/or several objectives) in a considerably systematic way.
The first impedance shaping control problem is to reduce voltage overshoot under load
changes and minimize the size of passive filter components in DC-DC converters. Subsequently,
current and voltage controllers for a three-phase DC-AC inverter are designed
to achieve robust system stability for a wide variety of filters. The least conservative
robust stability condition, with grid impedance being the main source of uncertainty, is
the passivity index. In the case of current controllers, the impact of higher loops on
impedance-based stability is also analyzed by an additional index: maximum singular
value. Each of the indices is applied to a given frequency range. Finally, these conditions
are included in the one-step design of the controller of a back-to-back converter used
to operate doubly fed induction generators (type-3 wind turbines) present in some wind
farms. This solution avoids the sub-synchronous oscillation problems, derived from transmission
lines with series compensation capacitors, faced by these wind farms. Simulation
and experimental results demonstrate the effectiveness and versatility of the proposa
Друга міжнародна конференція зі сталого майбутнього: екологічні, технологічні, соціальні та економічні питання (ICSF 2021). Кривий Ріг, Україна, 19-21 травня 2021 року
Second International Conference on Sustainable Futures: Environmental, Technological, Social and Economic Matters (ICSF 2021). Kryvyi Rih, Ukraine, May 19-21, 2021.Друга міжнародна конференція зі сталого майбутнього: екологічні, технологічні, соціальні та економічні питання (ICSF 2021). Кривий Ріг, Україна, 19-21 травня 2021 року
New Approaches in Automation and Robotics
The book New Approaches in Automation and Robotics offers in 22 chapters a collection of recent developments in automation, robotics as well as control theory. It is dedicated to researchers in science and industry, students, and practicing engineers, who wish to update and enhance their knowledge on modern methods and innovative applications. The authors and editor of this book wish to motivate people, especially under-graduate students, to get involved with the interesting field of robotics and mechatronics. We hope that the ideas and concepts presented in this book are useful for your own work and could contribute to problem solving in similar applications as well. It is clear, however, that the wide area of automation and robotics can only be highlighted at several spots but not completely covered by a single book