Hybridikäytön mitoitus liikkuvan työkoneen energian talteenottojärjestelmäksi

Työssä tarkastellaan sähköisiä energian talteenottomahdollisuuksia liikkuvissa työkoneissa. Työssä esitetään kolme erityyppistä liikkuvaan työkoneeseen soveltuvaa sähköisen energian talteenottojärjestelmää sekä mitoitetaan hybridikäyttö kahdelle erityyppiselle työkonesovellukselle kuormituskäyrien perusteella. Lisäksi työssä lasketaan hybridijärjestelmää käyttämällä saavutettava energiansäästö nykyiseen käyttöön verrattuna.

Tuulivoimakäyttö sähköverkon vikatilanteissa

Tämä työ on tehty Lappeenrannan teknillisessä yliopistossa, meneillään olevan tuulivoimalasimulaattorin kehitystyön yhteydessä. Työssä käydään läpi simulaattorissa käytettyjen generaattorisillan ja verkkosillan säätöperiaatteita, tehdään katsaus siirtoverkon jännitevikoihin sekä tuulivoimalan toimintaan näissä vikatilanteissa. Työn varsinainen tutkimuskohde on verkkosillan säädön toiminnan simuloiminen siirtoverkon jännitevioissa ja säädön parannusehdotukset.

Taajuusmuuttajaohjatun pumppukäytön simulointimallin kehittäminen ja testaus

Pumppukäytöt vastaavat noin neljänneksestä Euroopan sähkömoottoreissa kulutettavasta sähkötehosta. Energian kallistumisen vuoksi energian säästämisestä ja energiatehokkuudesta on tullut yhä tärkeämpää. Taajuusmuuttajat ovat tuoneet yksinkertaisen säätötavan, jolla suurimmassa osassa pumppukäyttöjä voidaan saada huomattavia energiasäästöjä. Koko energiansäästöpotentiaalin hyödyntämiseksi täytyy kuitenkin pumppujen toimintaa tarkkailla. Tarkkailu voidaan toteuttaa käyttämällä taajuusmuuttajan sisäisiä mittauksia pumpun toimintapisteen määrittämiseen. Tässä työssä muodostetaan kaksi simulointimallia, joilla voidaan tutkia pumppukäytön toimintapistettä ja energiatehokkuutta. Pumpattavan nesteen ominaisuuksien vaikutusta malleihin tutkitaan ja tapoja korjata virhettä selvitetään. Mallien tuottamia estimaatteja verrataan laboratorio ja pilot-kohteiden mittauksiin. Pilot-kohteiden avulla tutkitaan voidaanko simulointimalleja käyttää teollisuuden energiansäästöpotentiaalia omaavien pumppukäyttöjen havaitsemiseen.

Desarrollo de mejoras y nuevas funcionalidades a eXeLearning.net y colaboración con la comunidad de software libre exelearning.net

En este TFM se detallan las mejoras realizadas a la aplicación eXeLearning.net, así como otras aportaciones a la comunidad realizadas durante el proyecto de fin de máster de Software libre. eXeLearning.net es una aplicación de software libre para la creación de materiales educativos digitales, desarrollada en Python, con una interfaz web (HTML + JavaScript). En este proyecto se desarrollaron entre otras cosas: un repositorio de estilos en la web oficial de la aplicación, disponibles para su descarga desde la aplicación de escritorio, la creación y mantenimiento de un repositorio en Launchpad y una funcionalidad para publicar los contenidos creados con eXeLearning.net directamente en Google Drive.

Módulo eletrônico de controle para válvulas solenóides

This technical note describes a new and simple electronic circuit for driving solenoid valves. The circuit is based on a single integrated circuit DRV103, which is able to drive resistive or inductive loads up to 1.5 A. Switching of 12-V loads can be controlled by TTLlevel signals in two distinct steps. Initially, 12 V is applied during 110 ms, followed by 4.2 V RMS until the end of the activation TTL pulse. This mode of operation is particularly suitable to drive solenoids, because it requires a higher voltage to start and a lower maintenance voltage. By using this circuit, power consumption and heating are reduced and the solenoid lifetime is enhanced. Moreover, this circuit is specially appropriated to build computercontrolled solenoid valves systems.

Role of PheE15 gate in ligand entry and nitric oxide detoxification function of Mycobacterium tuberculosis truncated hemoglobin N

The truncated hemoglobin N, HbN, of Mycobacterium tuberculosis is endowed with a potent nitric oxide dioxygenase (NOD) activity that allows it to relieve nitrosative stress and enhance in vivo survival of its host. Despite its small size, the protein matrix of HbN hosts a two-branched tunnel, consisting of orthogonal short and long channels, that connects the heme active site to the protein surface. A novel dual-path mechanism has been suggested to drive migration of O(2) and NO to the distal heme cavity. While oxygen migrates mainly by the short path, a ligand-induced conformational change regulates opening of the long tunnel branch for NO, via a phenylalanine (PheE15) residue that acts as a gate. Site-directed mutagenesis and molecular simulations have been used to examine the gating role played by PheE15 in modulating the NOD function of HbN. Mutants carrying replacement of PheE15 with alanine, isoleucine, tyrosine and tryptophan have similar O(2)/CO association kinetics, but display significant reduction in their NOD function. Molecular simulations substantiated that mutation at the PheE15 gate confers significant changes in the long tunnel, and therefore may affect the migration of ligands. These results support the pivotal role of PheE15 gate in modulating the diffusion of NO via the long tunnel branch in the oxygenated protein, and hence the NOD function of HbN.

Energy efficiency parameters in variable speed drives

The main purpose of this thesis is to measure and evaluate how accurately the current energy saving calculation in ABB’s new variable speed drive ACS850 works. The main topic of this thesis is energy-efficiency parameters. At the beginning of this thesis centrifugal pump, squirrel cage motor and variable speed drive, including some equations related to them, are being introduced. Also methods of throttling control and variable speed drive control of centrifugal pumps are being introduced. These subjects are introduced because the energy saving calculation in ACS850 is related to the centrifugal pumps usually driven by squirrel cage motors. The theory also includes short section about specific energy of pumping. Before measurements the current energy saving calculation of ACS850 is being introduced and analyzed. The measurements part includes introduction of measuring equipment, measurement results, summary and analysis of the measurements. At the end of this thesis a proposal for an improvement to the current energy saving calculation is being introduced and few proposals are made for new energy-efficiency parameters, which could be added to variable speed drives. At the end are also thoughts

Taajuusmuttajan vanheneminen syklisissä käytöissä

Tässä työssä tarkastellaan taajuusmuuttajan vanhenemista syklisissä käytöissä puolijohdetehokomponenttien osalta. Laitteiden vikaantumisprosessien analysoimiseksi työssä suunnitellaan syklinen kestotestausjärjestelmä, joka mahdollistaa useamman taajuusmuuttajan yhtäaikaisen vanhentamisen. Jaksottaisesti toistuvat kuormitussyklit rasittavat termomekaanisesti taajuusmuuttajan tehomoduulin sisäisiä rakenteita suurten lämpötilavaihtelujen johdosta. Teoriaosuuden pääpaino kohdistuu puolijohdetehokomponenttien rakenteeseen, vikaantumisprosesseihin ja eliniän kartoittamiseen. Työssä käydään läpi yleisimpien pienijännitteisten moottorinohjausinverttereiden tehomoduulien mekaaniset rakenteet, tyypillisemmät syklisestä kuormituksesta johtuvat vikaantumisprosessit sekä puolijohdetehokomponenttivalmistajien käyttämät syklisen eliniän testausmenetelmät. Loppuosassa työtä suunnitellaan taajuusmuuttajan syklinen kestotestausjärjestelmä laitteiden keinotekoista vanhentamista varten. Testausjärjestelmällä voidaan kuormittaa useampaa taajuusmuuttajaa vuorottain mielivaltaisella kuormitusvirtaprofiililla. Laitteita vanhennettiin kaksi testierää kuormittamalla niitä jaksottaisesti hissikäytön tyypillisellä kuormitusprofiililla. Puolijohdetehokomponentin vanhenemisen edistystä seurattiin termisen impedanssiketjun mittausmenetelmällä, joka perustuu IGBT:n kollektoriemitterijännitteen lämpötilariippuvuuteen. Testilaitteiden puolijohdetehokomponentit hajosivat syklisen eliniän päättymiseen teoriassa esitettyjen vikaantumisprosessien seurauksesta. Tehomoduulien vika-analyysi osoittaa syklisen kestotestausjärjestelmän soveltuvaksi menetelmäksi tutkia erilaisten kuormitusprofiilien vaikutusta taajuusmuuttajan vanhenemiseen.

Radio Frequency Measurement Method for Detecting Bearing Currents in Induction Motors

Induction motors are widely used in industry, and they are generally considered very reliable. They often have a critical role in industrial processes, and their failure can lead to significant losses as a result of shutdown times. Typical failures of induction motors can be classified into stator, rotor, and bearing failures. One of the reasons for a bearing damage and eventually a bearing failure is bearing currents. Bearing currents in induction motors can be divided into two main categories; classical bearing currents and inverter-induced bearing currents. A bearing damage caused by bearing currents results, for instance, from electrical discharges that take place through the lubricant film between the raceways of the inner and the outer ring and the rolling elements of a bearing. This phenomenon can be considered similar to the one of electrical discharge machining, where material is removed by a series of rapidly recurring electrical arcing discharges between an electrode and a workpiece. This thesis concentrates on bearing currents with a special reference to bearing current detection in induction motors. A bearing current detection method based on radio frequency impulse reception and detection is studied. The thesis describes how a motor can work as a “spark gap” transmitter and discusses a discharge in a bearing as a source of radio frequency impulse. It is shown that a discharge, occurring due to bearing currents, can be detected at a distance of several meters from the motor. The issues of interference, detection, and location techniques are discussed. The applicability of the method is shown with a series of measurements with a specially constructed test motor and an unmodified frequency-converter-driven motor. The radio frequency method studied provides a nonintrusive method to detect harmful bearing currents in the drive system. If bearing current mitigation techniques are applied, their effectiveness can be immediately verified with the proposed method. The method also gives a tool to estimate the harmfulness of the bearing currents by making it possible to detect and locate individual discharges inside the bearings of electric motors.

Electrical machine in a Hybrid Electrical Vehicle

Hybrid electric vehicles (HEV) have attracted very much attention during the latest years. Increasing environmental concern and an increase in fuel prices are key factors for the growing interest towards the HEV. In a hybrid electric vehicle the power train consists of both a mechanical power system and an electric power transmission system. The major subsystems in the mechanical power system are the internal combustion engine which powers the vehicle; electric power transmission including an energy storage, power electronic inverter, hybrid control system; the electric motor drive that runs either in the generating mode or in the motoring mode to process the power flow between the energy storage and the electrical machine. This research includes two advanced electric motors for a parallel hybrid: induction machine and permanent magnets synchronous machine. In the thesis an induction motor and a permanent magnet motor are compared as propulsion motors. Electric energy storages are also studied.

The single principle of compositional data analysis, continuing fallacies, confusionsand misunderstandings and some suggested remedies

In any discipline, where uncertainty and variability are present, it is important to haveprinciples which are accepted as inviolate and which should therefore drive statisticalmodelling, statistical analysis of data and any inferences from such an analysis.Despite the fact that two such principles have existed over the last two decades andfrom these a sensible, meaningful methodology has been developed for the statisticalanalysis of compositional data, the application of inappropriate and/or meaninglessmethods persists in many areas of application. This paper identifies at least tencommon fallacies and confusions in compositional data analysis with illustrativeexamples and provides readers with necessary, and hopefully sufficient, arguments topersuade the culprits why and how they should amend their ways

Efectos del alcohol y conducción de vehículos: creencias y conductas de los jóvenes

Traffic accidents are one of the causes of death for people between 1 and 45 years old. Many studies verify that the road accidents are related with the consumption of alcohol. This problem, is especially important in the young people and it is increased during dawns of the weekends. Some studies underline the lack of information and knowledge of many young people concerning law on alcohol consummation when driving and the effects of this drug on consumers. Another problem is the amount of mistaken beliefs on what to do neutralize the alcohol’s effect before drive. The objective of our study is to evaluate, in university students, the knowledge of the rules of driving behavior included in the circulation code and the personal beliefs about the effects of the alcohol in driving, and to find the frequency and the circumstances in which young people drive after alcohol consummation. The results suggest many actions that may be considered in the design of preventive campaigns that promotes safety road behavior in order to increase their effectivity

Multichannel distribution strategy for electrical equipment marketing

The thesis examines System Integration and original equipment manufacturer (OEM) channel in the St. Petersburg drives market. The aim of the study was to increase understanding the relationship between OEM and SI and producers, problems and ongoing trends. The collected data was analyzed in order to find out which features of a power electronic drive product exercise a significant influence for the Russian companies decision. An essential part of this study was interviews as primary information sources, organized with SI and OEM companies which represented the basic SPb industry segments. The wholesalers and end users are left out from the analysis. The collected data was analyzed in order to find out which features of a power electronic drive product exercise a significant influence for the Russian companies decision.

Cómo mejorar la efectividad en un jugador de tenis: Modelos de regresión log-lineales

La efectividad en el deporte hace referencia al impacto alcanzado por una acción llevada a cabo en condiciones habituales, estando presente en la ejecución de cualquier actividad física, referida a la capacidad para producir el efecto deseado, y está relacionada con la e$cacia, entendida como el efecto de una acción llevada a cabo en las mejores condiciones posibles, y que tiene como objetivo, lograr la meta, o conseguir el triunfo. El objetivo de este trabajo consistió en identificar la relación entre la zona y el tipo de golpe, desde la cual el tenista presenta mayor y menor efectividad en el juego. Para ello se observó a un tenista durante 12 entrenamientos con un rival de nivel equivalente, según la ATP, durante la temporada 2012-2013, registrando su situación en la cancha y el tipo de golpe de todas las devoluciones con éxito, entendido como obtención del punto o recuperación del saque. Se crearon tres criterios categóricos que constituyen un instrumento de observación para registrar el juego del tenista en la zona horizontal, y la zona vertical de la pista, además del tipo de golpe que realiza en términos de drive, revés, smash y dejada. Utilizando la técnica de regresión log-lineal, se obtuvieron resultados que indican que el jugador presenta una menor efectividad en los golpes realizados desde el lado izquierdo, y muestra una mayor efectividad en el drive y revés ejecutados desde media pista o fondo del lado derecho. La interpretación de los resultados aporta información sobre las localizaciones en la pista y los golpes, relacionados con su mayor y menor efectividad.

Pla de màrqueting per al llançament d'un nou producte en el mercat dels motors elèctrics per a bancs de proves

Ningú no dubte ja del canvi de mentalitat que s’ha produït en els darrers anys en els compradors pel què fa al mercat de l’automòbil. La seguretat i el respecte per el medi ambient, són actualment dos dels factors claus que el consumidor té en compte a l’hora de comprar un vehicle. D’altra banda en els darrers anys la Unió Europea, ha fixat tota una sèrie normatives per tal de reduir les emissions nocives a l’atmosfera. Així doncs, més seguretat i menys emissions, signifiquen vehicles que incorporin components i sistemas cada cop més sofisticats, els quals, a la vegada, necessiten de bancs d’assaig i equips de test per tal de ser validats. Aquest fet ha provocat una revolució dins dels sistemes de test per a vehicles, per als quals han augmentat enormement les exigències en quan a precisions i repetibilitat per tal d’intentar reproduir, amb la màxima fiabilitat possible, les condicions de treball que hauran de suportar els components durant el seu ús real. Les característiques dels motors elèctrics, resulten ideals per a accionar aquest tipus d’aplicacions, ja que permeten un control del parell molt acurat i una repetibilitat quasi perfecte enfront d’altres sistemas utilitzats fins no fa massa temps. Aquesta demanda creixent d’aquest tipus de màquines elèctriques, obra una nova oportunitat de negoci per a les empreses fabricants de motors elèctrics. L’objectiu principal d’aquest treball és identificar i satisfer les necessitats dels clients, dins d’un mercat industrial concret: el mercat dels motors elèctrics per a bancs de proves de components per a la indústria de l’automoció. La fita és doncs la de proporcionar les eines necessàries per tal de que una empresa, fabricant de motors elèctrics de velocitat variable, pugui realitzar el disseny, desenvolupament i llançament comercial d’un nou tipus de motor, específicament pensat per aquest mercat, amb les màximes garanties d’èxit. Com a principal conclusió, el treball argumenta que el nou producte representa una oportunitat de negoci força atractiva i rendible per a l’empresa, i permetrà diversificar la oferta de la companyia cap a un nou sector fins ara no explotat.