Permanent magnet synchronous generator design solution for large directdrive wind turbines: Thermal behavior of the LC DD-PMSG

Wind is one of the most compelling forms of indirect solar energy. Available now, the conversion of wind power into electricity is and will continue to be an important element of energy self-sufficiency planning. This paper is one in a series intended to report on the development of a new type of generator for wind energy; a compact, high-power, direct-drive permanent magnet synchronous generator (DD-PMSG) that uses direct liquid cooling (LC) of the stator windings to manage Joule heating losses. The main param-eters of the subject LC DD-PMSG are 8 MW, 3.3 kV, and 11 Hz. The stator winding is cooled directly by deionized water, which flows through the continuous hollow conductor of each stator tooth-coil winding. The design of the machine is to a large degree subordinate to the use of these solid-copper tooth-coils. Both steady-state and timedependent temperature distributions for LC DD-PMSG were examined with calculations based on a lumpedparameter thermal model, which makes it possible to account for uneven heat loss distribution in the stator conductors and the conductor cooling system. Transient calculations reveal the copper winding temperature distribution for an example duty cycle during variable-speed wind turbine operation. The cooling performance of the liquid cooled tooth-coil design was predicted via finite element analysis. An instrumented cooling loop featuring a pair of LC tooth-coils embedded in a lamination stack was built and laboratory tested to verify the analytical model. Predicted and measured results were in agreement, confirming the predicted satisfactory operation of the LC DD-PMSG cooling technology approach as a whole.

Spectrally Tuned Lanthanide Photoluminescence for Point-of-Care Testing

Point-of-care (POC) –diagnostics is a field with rapidly growing market share. As these applications become more widely used, there is an increasing pressure to improve their performance to match the one of a central laboratory tests. Lanthanide luminescence has been widely utilized in diagnostics because of the numerous advantages gained by the utilization of time-resolved or anti-Stokes detection. So far the use of lanthanide labels in POC has been scarce due to limitations set by the instrumentation required for their detection and the shortcomings, e.g. low brightness, of these labels. Along with the advances in the research of lanthanide luminescence, and in the field of semiconductors, these materials are becoming a feasible alternative for the signal generation also in the future POC assays. The aim of this thesis was to explore ways of utilizing time-resolved detection or anti-Stokes detection in POC applications. The long-lived fluorescence for the time-resolved measurement can be produced with lanthanide chelates. The ultraviolet (UV) excitation required by these chelates is cumbersome to produce with POC compatible fluorescence readers. In this thesis the use of a novel light-harvesting ligand was studied. This molecule can be used to excite Eu(III)-ions at wavelengths extending up to visible part of the spectrum. An enhancement solution based on this ligand showed a good performance in a proof-of-concept -bioaffinity assay and produced a bright signal upon 365 nm excitation thanks to the high molar absorptivity of the chelate. These features are crucial when developing miniaturized readers for the time-resolved detection of fluorescence. Upconverting phosphors (UCPs) were studied as an internal light source in glucose-sensing dry chemistry test strips and ways of utilizing their various emission wavelengths and near-infrared excitation were explored. The use of nanosized NaYF :Yb3+,Tm3+-particles enabled the replacement of an external UV-light source with a NIR-laser and gave an additional degree of freedom in the optical setup of the detector instrument. The new method enabled a blood glucose measurement with results comparable to a current standard method of measuring reflectance. Microsized visible emitting UCPs were used in a similar manner, but with a broad absorbing indicator compound filtering the excitation and emission wavelengths of the UCP. This approach resulted in a novel way of benefitting from the non-linear relationship between the excitation power and emission intensity of the UCPs, and enabled the amplification of the signal response from the indicator dye.

The role of import intermediary companies in the Russian imports from the EU A case study of a Russian industrial company’s point of view on import intermediaries

The literature on agency suggests different implications for the use of export intermediaries. However, only few studies provide a view on import intermediaries. This thesis tries for its part to fill this research gap by studying the import intermediaries in the EU–Russia trade from a Russian industrial company’s point of view. The aim is to describe import intermediation and explain the need for import intermediary companies in the EU–Russia trade. The theoretical framework of this thesis originates from an article by Peng and York (2001), in which they study the performance of export intermediaries. This thesis applies resource-based theory, transaction cost theory and agency cost theory, following the idea of Peng and York. The resource-based theory approach is utilised for describing an ideal import intermediary company, and transaction cost theory provides a basis for understanding the benefits of using the services of import intermediary companies, while agency cost theory is applied in order to understand the risks the Russian industrial company faces when it decides to use the services of import intermediaries. The study is performed in the form of a case interview with a representative of a major Russian metallurgy company. The results of the study suggest that an ideal intermediary has the skills required specifically for the imports process, in order to save time and money of the principal company. The intermediary company helps reducing the amount of time the managers and the staff of the principal company use to make imports possible, thus reducing the salary costs and providing the possibility to concentrate on the company’s core competencies. The benefits of using the services of import intermediary companies are the reduced transaction costs, especially salary costs that are minimised because of the effectiveness and specialisation of import intermediaries. Intermediaries are specialised in the imports process and thus need less time and resources to organise the imports. They also help to reduce the fixed salary costs, because their services can be used only when needed. The risks of being misled by intermediaries are minimised by the competition on the import intermediary market. In case an intermediary attempts fraud, it gets replaced by its rival.

Effect of the implementation of the Hazard Analysis Critical Control Point (HACCP) prerequisite program in an institutional foodservice unit in Southern Brazil

The aims of this study were to investigate the hygienic practices in the food production of an institutional foodservice unit in Southern Brazil and to evaluate the effect of implementing good food handling practices and standard operational procedures using microbiological hygiene indicators. An initial survey of the general operating conditions classified the unit as regular in terms of compliance with State safety guidelines for food service establishments. An action plan that incorporated the correction of noncompliance issues and the training of food handlers in good food handling practices and standard operational procedures were then implemented. The results of the microbiological analysis of utensils, preparation surfaces, food handlers' hands, water, and ambient air were recorded before and after the implementation of the action plan. The results showed that the implementation of this type of practice leads to the production of safer foods.

Hygienic-sanitary working practices and implementation of a Hazard Analysis and Critical Control Point (HACCP) plan in lobster processing industries

This study aimed to verify the hygienic-sanitary working practices and to create and implement a Hazard Analysis Critical Control Point (HACCP) in two lobster processing industries in Pernambuco State, Brazil. The industries studied process frozen whole lobsters, frozen whole cooked lobsters, and frozen lobster tails for exportation. The application of the hygienic-sanitary checklist in the industries analyzed achieved conformity rates over 96% to the aspects evaluated. The use of the Hazard Analysis Critical Control Point (HACCP) plan resulted in the detection of two critical control points (CCPs) including the receiving and classification steps in the processing of frozen lobster and frozen lobster tails, and an additional critical control point (CCP) was detected during the cooking step of processing of the whole frozen cooked lobster. The proper implementation of the Hazard Analysis Critical Control Point (HACCP) plan in the lobster processing industries studied proved to be the safest and most cost-effective method to monitor each critical control point (CCP) hazards.

Biomarkkerit sepsiksen diagnostiikassa sekä Kvantitatiivisen prokalsitoniini-immunomäärityksen pystyttäminen ja optimointi point-of-care-ympäristöön

Termiä sepsis käytetään infektion aiheuttamasta yleisestä tulehdusreaktio-oireyhtymästä. Biokemiallinen merkkiaine eli biomarkkeri on aine, joka objektiivisesti mitattuna ja arvioituna toimii indikaattorina erottaen toisistaan normaalit biologiset prosessit ja patogeeniset prosessit. Lisäksi biomarkkeri saattaa osoittaa farmakologisen vasteen lääkehoidolle. Tutkielman kirjallisessa osassa on esitelty ja verrattu toisiinsa jo kliinisessä käytössä olevia sekä lupaavia, vielä tutkimusvaiheessa olevia, sepsiksen biomerkkiaineita. Lisäksi tutkielmassa on tarkasteltu sepsiksen todentamisen, tunnistamisen ja hoidon tulevaisuudennäkymiä. Prokalsitoniini (PCT) on eräs jo kliinisessä käytössä oleva sepsiksen biomerkkiaine. Tutkielman kokeellisessa osassa pystytettiin teho-osastoille suunnattu pikatesti PCT:n mittaamiseen aikaerotteista fluoresenssiteknologiaa hyödyntävälle AQT-järjestelmälle (DHR Finland Oy, Innotrac Diagnostics, Suomi). Järjestelmä mittaa 20–30 minuutissa biomerkkiainepitoisuuden. Tavoitteena oli löytää sopiva vasta-ainepari ja pystyttää kaksipuoleinen immunomääritys, jonka analyyttinen herkkyys on alle 0,02 ng/ml:ssa. Työssä tutkittiin biotinyloidun kokonaisen vasta-aineen ja paikkaspesifisesti biotinyloidun antigeenia sitovan fragmentin (engl. fragment antigen binding, Fab) toimivuutta sitojamolekyylinä. Lisäksi työssä verrattiin kahden eri leimamolekyylin, 9 hampaisen europiumkelaatin sekä Innotracissa kehitetyn tähtikelaatin, toimivuutta PCT-immunomäärityksessä. Vasta-aineiden mahdolliset ristireaktiot testattiin ja määritystä testattiin alustavasti eri näytematriiseissa. Työssä löydettiin 5 vasta-aineparia, joiden analyyttinen herkkyys oli alle 0,02 ng/ml:ssa. Aiemmin testattuja vasta-ainepareja parempi analyyttinen herkkyys johtui todennäköisesti yhden uuden leimavasta-aineen paremmasta affiniteetistä. Tähtikelaatilla leimatulla vasta-aineella analyyttinen herkkyys parani lähes viisinkertaisesti, kun sitä verrattiin 9-hampaisella euroopiumkelaatilla leimatun vasta-aineen määritykseen. Havaittiin myös, että Fab-fragmentilla mitattiin määrityksissä lähes kaksi kertaa suuremmat signaali-taustasuhteet, kun sitä verrattiin kokonaiseen vasta-aineeseen, tietyllä vasta-aineparilla. Tämä johtui luultavasti steeristen esteiden vähenemisestä. Näytematriisilla ei todettu olevan vaikutusta määritykseen, eikä ristireaktioita havaittu. Kehitetyn määrityksen suoriutumista verrattiin markkinoilla olevaan BRAHMS AG:n (Saksa) PCT-määritykseen käyttäen potilasnäytteitä. Korrelaatiokertoimet potilasnäytevertailuissa olivat 0,965–0,989 ja näytteiden mitatuissa pitoisuuksissa oli tasoero.

Heat-transfer improvements in an axial-flux permanent-magnet synchronous machine

Axial-flux machines tend to have cooling difficulties since it is difficult to arrange continuous heat path between the stator stack and the frame. One important reason for this is that no shrink fitting of the stator is possible in an axial-flux machine. Using of liquid-cooled end shields does not alone solve this issue. Cooling of the rotor and the end windings may also be difficult at least in case of two-stator-single-rotor construction where air circulation in the rotor and in the end-winding areas may be difficult to arrange. If the rotor has significant losses air circulation via the rotor and behind the stator yokes should be arranged which, again, weakens the stator cooling. In this paper we study a novel way of using copper bars as extra heat transfer paths between the stator teeth and liquid cooling pools in the end shields. After this the end windings still suffer of low thermal conductivity and means for improving this by high-heat-conductance material was also studied. The design principle of each cooling system is presented in details. Thermal models based on Computational Fluid Dynamics (CFD) are used to analyse the temperature distribution in the machine. Measurement results are provided from different versions of the machine. The results show that significant improvements in the cooling can be gained by these steps.

Evaluation of the Efficiency of Line-Start Permanent-Magnet Machines as a Function of the Operating Temperature

The standard squirrel-cage induction machine has nearly reached its maximum efficiency. In order to further increase the energy efficiency of electrical machines, the use of permanent magnets in combination with the robust design and the line start capability of the induction machine is extensively investigated. Many experimental designs have been suggested in literature, but recently, these line-start permanent-magnet machines (LSPMMs) have become off-the-shelf products available in a power range up to 7.5 kW. The permanent magnet flux density is a function of the operating temperature. Consequently, the temperature will affect almost every electrical quantity of the machine, including current, torque, and efficiency. In this paper, the efficiency of an off-the-shelf 4-kW three-phase LSPMM is evaluated as a function of the temperature by both finite-element modeling and by practical measurements. In order to obtain stator, rotor, and permanent magnet temperatures, lumped thermal modeling is used.

The role of import intermediary companies in the Russian imports from the EU A case study of a Russian industrial company’s point of view on import intermediaries

The literature on agency suggests different implications for the use of export intermediaries. However, only few studies provide a view on import intermediaries. This thesis tries for its part to fill this research gap by studying the import intermediaries in the EU–Russia trade from a Russian industrial company’s point of view. The aim is to describe import intermediation and explain the need for import intermediary companies in the EU–Russia trade. The theoretical framework of this thesis originates from an article by Peng and York (2001), in which they study the performance of export intermediaries. This thesis applies resource-based theory, transaction cost theory and agency cost theory, following the idea of Peng and York. The resource-based theory approach is utilised for describing an ideal import intermediary company, and transaction cost theory provides a basis for understanding the benefits of using the services of import intermediary companies, while agency cost theory is applied in order to understand the risks the Russian industrial company faces when it decides to use the services of import intermediaries. The study is performed in the form of a case interview with a representative of a major Russian metallurgy company. The results of the study suggest that an ideal intermediary has the skills required specifically for the imports process, in order to save time and money of the principal company. The intermediary company helps reducing the amount of time the managers and the staff of the principal company use to make imports possible, thus reducing the salary costs and providing the possibility to concentrate on the company’s core competencies. The benefits of using the services of import intermediary companies are the reduced transaction costs, especially salary costs that are minimised because of the effectiveness and specialisation of import intermediaries. Intermediaries are specialised in the imports process and thus need less time and resources to organise the imports. They also help to reduce the fixed salary costs, because their services can be used only when needed. The risks of being misled by intermediaries are minimised by the competition on the import intermediary market. In case an intermediary attempts fraud, it gets replaced by its rival.

ATTITUDES TOWARD RUSSIAN CUSTOMERS IN THE FINNISH RETAIL TRADE SECTOR – A salesperson’s point of view

The amount of Russian tourists in Finland has increased significantly in the past years. The impact of Russian tourism to the Finnish retail trade sector is enormous, since Russian tourists often spend a lot of money particularly on shopping. Shopping tourism is mainly focused in the near border cities, such as Imatra and Lappeenranta, and in addition in Helsinki metropolitan area. The purpose of this study is to map the attitudes and perceptions of the sales personnel who are working in the Finnish retail trade sector towards Russian customers and to discover which elements affect these attitudes. The theories in this study are based on cultural elements and elements related to sales behavior and performance. Cultural differences between Finland and Russia, cultural distance and cultural intelligence form the cultural aspect of this study. Customer orientation vs. sales orientation (SOCO), adaptive selling, selling skills and job competency, salesperson’s affect and empathy toward customers, and job autonomy form the elements concerning sales behavior and performance. Furthermore, the attitude – behavior link, based on social psychology is addressed. A survey was conducted in two retail trade chains operating in Finland. These retail companies have stores and department stores in different geographical areas in Finland and the survey was conducted in altogether 19 cities. In addition to the theories that were discussed, two expert interviews were conducted in order to get a deeper understanding of the phenomenon at hand. Moreover the interviews helped in the formulation of the hypotheses and the questionnaire design. The questionnaires were sent directly to the stores, where they were placed so that they were available for the sales personnel. Altogether 487 usable responses were collected. The returned questionnaires were analyzed with IBM SPSS 21 statistics program. The results of this study indicated that the attitudes toward Russian customers are more negative compared to other foreign customers. However, the respondents’ attitudes toward and perceptions of Russian customers varied a lot. From the background variables age, education level, length of employment in current workplace, and length of experience in customer service had an effect on the attitudes of the respondents. In addition, the perceptions of Russian customers were more positive in the Eastern Finland compared to Helsinki metropolitan area. The cultural elements; cultural knowledge, cultural distance and cultural intelligence all affected the attitudes of the respondents. From the elements related to sales behavior and performance customer orientation, salesperson’s affect and empathy toward customers, and perceived job autonomy had an effect on the attitudes

Juridisen kaksinkertaisen verotuksen problematiikka kansainvälisessä yritystoiminnassa

Tässä tutkielmassa tarkastellaan kansainvälisessä yritystoiminnassa esiintyviä juridisen kaksinkertaisen verotuksen ongelmatilanteita suomalaisten yritysten näkökulmasta. Tutkielmassa pohditaan lisäksi yritysten omaa roolia osana kaksinkertaisen verotuksen tilanteita. Juridista kaksinkertaista verotusta muodostuu, kun sama yhtiö maksaa samasta tulosta veroa kahteen valtioon. Teoriaosio etenee verotusoikeuden määrittämisestä kaksinkertaisen verotuksen muodostumiseen. Kaksinkertainen verotus pyritään poistamaan poistomenetelmällä, joka on Suomessa tavallisesti hyvitysmenetelmä. Ongelmatilanne muodostuu, kun kaksinkertaista verotusta ei saada tehokkaasti poistettua tulon lähdevaltion ja yhtiön asuinvaltion välillä. Tämä tutkielma on laadullinen tutkimus ja tutkimusmenetelmänä on käytetty teemahaastattelua. Tutkimustulokset osoittavat, että kvalifikaatiokonflikteissa juridisen kaksinkertaisen verotuksen ongelmatilanne esiintyy pääsääntöisesti rojalti-liiketulo -luokitteluristiriidan seurauksena. Kiinteän toimipaikan kvalifikaatio on harvinaisempi ongelmatilanne. Hyvitysmenetelmän suurimmat ongelmat esiintyvät puolestaan pääliikkeen tappiollisen liiketoiminnan johdosta. Toinen hyvitysmenetelmän ongelmakohta esiintyy, kun lähdeveron alainen tulo huomioidaan bruttotulosta, mutta ulkomaisen tulon hyvitys suoritetaan nettotulosta. Haastatteluiden perusteella on selvää, että yritysten oma rooli kaksinkertaisen verotuksen ehkäisyssä on merkittävä. Yrityksen omia vaikutusmahdollisuuksia ovat muun muassa riittävä ennakointikyky, dokumentointi, selkeät sopimukset ja asiantuntijuus.

Kaksoiskäämitty hybridibussin kestomagneettiajomoottori

Tämä työ on tehty Lappeenrannan teknilliselle yliopistolle, joka on suunnitellut ja toteuttanut hybridibussin. Hybridibussin ajomoottorissa käytetään kaksoiskäämitystä, joka mahdollistaa bussin ajamisen vikatilanteessa, jossa toinen käämityksistä on epäkunnossa. Työn tavoitteena on selvittää, millainen kaksoiskäämitys toimii parhaiten tämän hybridibussin kestomagneettiajomoottorissa. Työssä tutustutaan ajomoottoreihin ja niiltä vaadittaviin ominaisuuksiin sekä vikasietoisiin sähkömoottoreihin. Tutkimuksessa löydettyihin vikasietoisiin ajomoottoreihin perustuen päädyttiin neljään kaksoiskäämitysvaihtoehtoon. Näitä kaksoiskäämityksiä tutkittiin FE-analyysiä hyödyntäen. Kaksoiskäämitysten toimintaa simuloitiin nimellis- ja vikatilanteessa. Simuloinnin tuloksista selvisi, että kaksoiskäämitys, jossa jokaisessa urassa oli puolet yhtä käämitystä ja puolet toista (kaksoiskäämitys 1), ei toiminut kunnolla nimellistilanteessa eikä vikatilanteessa. Suurin ongelma oli vikatilanteessa aiheutuva suuri oikosulkuvirta. Kaksoiskäämitys, jossa kaksi napaa oli samaa käämitystä (kaksoiskäämitys 2), toimi moitteettomasti nimellistilanteessa. Vikatilanteen toiminnassa kuitenkin havaittiin epäjaksollisuutta magneettivuontiheydessä, mikä on haitallista moottorin käynnille ja vaaraksi roottorille. Kaksoiskäämityksiä, joista ensimmäisessä oli neljäsosa konetta samaa käämitystä (kaksoiskäämitys 3) ja toisessa puolet koneesta samaa käämitystä (kaksoiskäämitys 4), tutkittiin vikatilanteessa vain magneettivuontiheyden osalta. Puolet ja puolet käämityn koneen osalta magneettivuontiheys osottautui epäjaksolliseksi kuten oli odotettu. Neljäsosiksi käämityn koneen magneettivuontiheys oli säännöllisen jaksollinen. Nimellispisteessä kaksoiskäämityksillä 3 ja 4 havaittiin suuri vääntöväre verrattuna kaksoiskäämityksiin 1 ja 2. Johtopäätöksenä kaksoiskäämitys 3 vaikuttaa lupaavalta, mikäli suuri nimellispisteen vääntöväre saadaan hallintaan käyttämällä uravinoutta staattorissa.

Design and Material Selection of High-Speed Rotating Electrical Machines

The increasing emphasis on energy efficiency is starting to yield results in the reduction in greenhouse gas emissions; however, the effort is still far from sufficient. Therefore, new technical solutions that will enhance the efficiency of power generation systems are required to maintain the sustainable growth rate, without spoiling the environment. A reduction in greenhouse gas emissions is only possible with new low-carbon technologies, which enable high efficiencies. The role of the rotating electrical machine development is significant in the reduction of global emissions. A high proportion of the produced and consumed electrical energy is related to electrical machines. One of the technical solutions that enables high system efficiency on both the energy production and consumption sides is high-speed electrical machines. This type of electrical machines has a high system overall efficiency, a small footprint, and a high power density compared with conventional machines. Therefore, high-speed electrical machines are favoured by the manufacturers producing, for example, microturbines, compressors, gas compression applications, and air blowers. High-speed machine technology is challenging from the design point of view, and a lot of research is in progress both in academia and industry regarding the solution development. The solid technical basis is of importance in order to make an impact in the industry considering the climate change. This work describes the multidisciplinary design principles and material development in high-speed electrical machines. First, high-speed permanent magnet synchronous machines with six slots, two poles, and tooth-coil windings are discussed in this doctoral dissertation. These machines have unique features, which help in solving rotordynamic problems and reducing the manufacturing costs. Second, the materials for the high-speed machines are discussed in this work. The materials are among the key limiting factors in electrical machines, and to overcome this limit, an in-depth analysis of the material properties and behavior is required. Moreover, high-speed machines are sometimes operating in a harsh environment because they need to be as close as possible to the rotating tool and fully exploit their advantages. This sets extra requirements for the materials applied.