Search results for "Linear"

A Ferrite Tubular Linear Motor (FTLM): Analysis and design

2015

The electromagnetic linear machines have wide applications in the electromagnetic aircraft launch systems [1] and in transportation systems [2]. Additional energy saving and efficiency can be achieved using a linear motor in the refrigeration application [3]. Linear electromagnetic machines are also very suitable for high-speed packaging, manufacturing sectors and precision positioning. There are different linear motor topologies. Tubular permanent-magnets are particularly attractive since they have a high thrust force density and high efficiency, no end windings, and zero net attractive force between stator and armature. There are various tubular motor topologies, in which the armature may…

DESALINATION AND SEA WAVE TO PRODUCE FRESHWATER AND ENERGY FROM THE SEA. THE PROPOSAL OF A LINEAR GENERATOR FOR A WAVE ENERGY CONVERTER AND EVALUATIO…

2020

Testing a linear ironless generator for the sea wave energy harvesting

2022

Wave energy represents a "new entry"in the renewable energy sector; however, it is believed that in near future sea wave might have a key role for the electrical energy production, thanks its huge energy potential. In this context, the paper suggests an innovative ironless linear generator, that can be used as main component inside a point absorber. In order to exploit the wave energy potential in the Mediterranean Sea, the Engineering Department of Palermo University realized a first small-scale prototype of the electrical linear generator, that is the main component for the energy conversion.

An improved five-parameter model for photovoltaic modules

2010

This paper presents a new five-parameter model capable of analytically describing the I–V characteristic of a photovoltaic module for each generic condition of operative temperature and solar irradiance. The parameters of the equivalent electrical circuit are extracted by solving a system of equations based on data commonly issued by manufacturers in standard rating conditions with a trial and error process. The procedure, which does not require any special equations solver, can be easily coded into a short software routine using simple languages and finds the solution of the system of equations with the desired accuracy without needing to be guided towards solutions starting from fitted in…

Reduction of cogging force in linear generators for wave energy harvesting

2022

Due to huge energy potential of sea waves, many technologies have been proposed in the last few years. Some concepts have been developed and sometimes also tested in the open sea. Some prototypes use linear generators to directly convert the vertical motion of buoys into electrical energy. This solution minimizes the numbers of energy conversion steps, increasing the energy efficiency. At the same time, the limited numbers of components could also increase the reliability of the wave energy converter. For this reason, the development of linear generators is considered with great interest. This paper investigated the cogging force, a magnetic force due to the interaction between the magnets …

Adaptive type-2 fuzzy control of non-linear systems

2009

The paper describes the development of two different type-2 adaptive fuzzy logic controllers and their use for the control of a non linear system that is characterized by the presence of bifurcations and parameter uncertainty. Although a type-2 fuzzy logic controller is able to handle the non linearities and the uncertainties present in a system, its robustness and effectiveness can be increased by the use of an opportune adaptive algorithm. A simulation study was conducted to compare the behavior of adaptive controllers with that of simple type-1 and type-2 fuzzy logic controllers. The system to be controlled, used for the simulation, is a continuous bioreactor for the treatment of mixed w…

Adaptive type-2 fuzzy logic control of a bioreactor

2010

Two adaptive type-2 fuzzy logic controllers with minimum number of rules are developed and compared by simulation for control of a bioreactor in which aerobic alcoholic fermentation for the growth of Saccharomyces cerevisiae takes place. The bioreactor model is characterized by nonlinearity and parameter uncertainty. The first adaptive fuzzy controller is a type-2 fuzzy-neuro-predictive controller (T2FNPC) that combines the capability of type-2 fuzzy logic to handle uncertainties, with the ability of predictive control to predict future plant performance making use of a neural network model of the nonlinear system. The second adaptive fuzzy controller is instead a self-tuning type-2 PI cont…

Nonlinear fuzzy control of a fed-batch reactor for penicillin production

2012

Abstract The process of penicillin production is characterized by nonlinearities and parameter uncertainties that make it difficult to control. In the paper the development and testing of a multivariable fuzzy control system that makes use of type-2 fuzzy sets for the control of pH and temperature are described. The performance of the type-2 fuzzy logic control system (T2FLCS) is compared by simulation with that of a type-1 fuzzy logic control system (T1FLCS) and that of a control system with traditional proportional-integral-derivative (PID) controllers proposed in the literature. The fuzzy controllers are optimized using an ANFIS algorithm. The best results are obtained with the T2FLCS pa…

Control of a Non-isothermal CSTR by Type-2 Fuzzy Logic Controllers

2009

The paper describes the application of a type-2 fuzzy logic controller (FLC) to a non-isothermal continuous stirred tank reactor (CSTR) characterized by the presence of saddle node and Hopf bifurcations. Its performance is compared with a type-1 fuzzy logic controller performance. A full analysis of the uncontrolled CSTR dynamic was carried out and used for the feedback-feedforward fuzzy controllers development. Simulation results confirm the effectiveness and the robustness of the type-2 FLCs which outperform their type-1 counterparts, particularly when uncertainties are present in the system.

Control of a fermentator for the aerobic growth of saccharomyces cerevisiae by an adaptive type-2 fuzzy logic controller

2008

I controllori a logica fuzzy (FLCs) costituiscono una facile alternativa al controllo di sistemi che hanno un comportamento fortemente non lineare, facendo uso di fuzzy sets e di una logica fuzzy del 1° tipo. A dispetto della loro popolarità però, la ricerca ha mostrato come FLCs di 1° tipo, abbiano difficoltà a gestire e a minimizzare le incertezze presenti in un sistema. Una più grande complessità dei sistemi a logica fuzzy di 2° tipo rispetto quelli del 1° tipo, permette di gestire e conseguentemente di minimizzare gli effetti di una varietà di incertezze che non può essere direttamente gestita da FLS del 1° tipo. In questo lavoro si è considerato l’uso di un FLS del 2° tipo per il contr…