High-Speed Solid-Rotor Induction Machine – Electromagnetic Calculation and Design

Within the latest decade high-speed motor technology has been increasingly commonly applied within the range of medium and large power. More particularly, applications like such involved with gas movement and compression seem to be the most important area in which high-speed machines are used. In manufacturing the induction motor rotor core of one single piece of steel it is possible to achieve an extremely rigid rotor construction for the high-speed motor. In a mechanical sense, the solid rotor may be the best possible rotor construction. Unfortunately, the electromagnetic properties of a solid rotor are poorer than the properties of the traditional laminated rotor of an induction motor. This thesis analyses methods for improving the electromagnetic properties of a solid-rotor induction machine. The slip of the solid rotor is reduced notably if the solid rotor is axially slitted. The slitting patterns of the solid rotor are examined. It is shown how the slitting parameters affect the produced torque. Methods for decreasing the harmonic eddy currents on the surface of the rotor are also examined. The motivation for this is to improve the efficiency of the motor to reach the efficiency standard of a laminated rotor induction motor. To carry out these research tasks the finite element analysis is used. An analytical calculation of solid rotors based on the multi-layer transfer-matrix method is developed especially for the calculation of axially slitted solid rotors equipped with wellconducting end rings. The calculation results are verified by using the finite element analysis and laboratory measurements. The prototype motors of 250 – 300 kW and 140 Hz were tested to verify the results. Utilization factor data are given for several other prototypes the largest of which delivers 1000 kW at 12000 min-1.

Designing gainsharing model variations with logistics service company

This thesis studies, in collaboration with a Finnish logistics service company, gainsharing and the development of a gainsharing models in a logistics outsourcing context. The purpose of the study is to create various gainsharing model variations for the use of a service provider and its customers in order to develop and enhance the customer’s processes and operations, create savings and improve the collaboration between the companies. The study concentrates on offering gainsharing model alternatives for companies operating in internal logistics outsourcing context. Additionally, the prerequisites for the gainsharing arrangement are introduced. In the beginning of the study an extensive literature review is conducted. There are three main themes explored which are the collaboration in an outsourcing context, key account management and gainsharing philosophy. The customer expectations and experiences are gathered by interviewing case company’s employees and its key customers. In order to design the gainsharing model prototypes, customers and other experts’ knowledge and experiences are utilized. The result of this thesis is five gainsharing model variations that are based on the empirical and theoretical data. In addition, the instructions related to each created model are given to the case company, but are not available in this paper

Ketterän ohjelmistokehittämisen hyödyntäminen käyttöliittymäkehityksessä asiakkaiden todellisen tarpeen ymmärtämiseksi

Työn tavoitteena oli toimintatutkimuksen kautta tutkia ketterän ohjelmistokehityksen keinoin toteutetun käyttöliittymäkehityksen kykyä vastata asiakkaiden todellisiin tarpeisiin. Työssä haettiin tapaustutkimusyritykselle olemassa olevan työkalun uuden version käyttöliittymän toteutusvaihtoehtoja ja toteutettiin korkean tarkkuuden prototyyppejä näitä hyödyntäen. Ketterän ohjelmistokehityksen arvot ja periaatteet soveltuivat kehitysprosessissa käytettäviksi erinomaisesti. Iteratiivinen lähestymistapa kehitykseen ja läheinen yhteistyö tapaustutkimusyrityksen ja kandidaatintyöntekijän kanssa mahdollistivat yrityksen odotusten täyttämisen. Työkalun käyttöliittymä saatettiin tasolle, joka mahdollistaa jatkokehittämisen aloituksen. Kattavamman testauttamisen sisällyttäminen kehitysprosessiin olisi edesauttanut vielä paremman lopputuloksen saavuttamista.