Päällystävän paperikoneen vesikiertojen mallinnus

Työssä mallinnettiin kevyesti päällystettyjä aikakauslehtipapereita valmistavan paperikoneen vesikierrot Balas-ohjelman avulla. Mallin avulla selvitettiin paperikoneelle suunniteltujen muutosten vaikutuksia haitallisten aineiden tasoihin, muihin mallinnettuihin parametreihin ja vedenkulutukseen. Mallin luotettavuutta testattiin käytännössä tehdyillä muutoksilla. Vesinäytteistä haitallisina aineina tarkasteltiin lipofiilisten uuteaineiden, kalsiumin, alumiinin, raudan, piin ja sulfaatin pitoisuuksia. Pohjapaperinäytteistä määritettiin lipofiilisten uuteaineiden sekä kalsiumin ja alumiinin pitoisuudet. Paperikoneelle suunniteltuja muutoksia olivat kiekkosuodattimien kirkkaan suodoksen käyttö viiraosan suihkuvetenä ja päällystyksen yhteydessä syntyvän pastajätteen käyttö pohjapaperin täyteaineena. Kirkkaan suodoksen käytön lisäämisellä pyrittiin vähentämään raakaveden käyttöä. Pastajäte sisältää arvokkaita raaka-aineita, jotka kannattaisi hyödyntää paperitehtaalla. Nykyisin pastajäte kuljetetaan läjitysalueelle. Balas-mallin todettiin mallintavan melko luotettavasti liuenneiden haitallisten aineiden pitoisuuksien sekä muista parametreista muun muassa sakeuden ja tuhkapitoisuuden muutoksia. Pastajätteen palautuksen mallinnuksessa haitallisten aineiden pitoisuudet laskivat prosessissa. Tämä toteutui koeajossa, koska jätepastasta suurin osa oli vettä, joka huuhtoi prosessia. Kirkkaan suodoksen käyttö suihkuvetenä ei nostanut epäorgaanisten haitallisten aineiden pitoisuuksia niin paljon kuin malli ennusti. Todennäköisesti haitalliset aineet saostuivat tai poistuivat tuotteen mukana prosessista. Kirkassuodos-koeajon aikana otetussa pohjapaperinäytteessä kiinteän kalsiumin pitoisuus oli 40 % ja kiinteän alumiinin pitoisuus 11 % korkeampi mutta uuteaineiden pitoisuus 20 % alhaisempi kuin referenssipohjapaperissa.

Polttoaineseoksen ja prosessiolosuhteiden vaikutus kerrosleijukattilan tulistinalueen likaantumiseen

Työn tavoitteena oli löytää yhteys kerrosleijukattilaan syötetyn polttoaineseoksen sekä kattilan likaantumisen välille. Tulistinalueen likaantumista tutkittiin kahden kerrostumasondin avulla 28 päivää kestäneellä mittausjaksolla. Mittausten aikana otettiin näytteitä polttoaineseoksesta, lentotuhkasta sekä nuohouksen aikaisesta tuhkavirrasta. Mittausjakson jälkeen myös sondien tuhkakerrostumien pitoisuudet määritettiin. Mittausjakson aikana sondien jättöpinnoille muodostui tuhkakerrostumaa, joka voitiin poistaa nuohouksella, kun taas tulopinnalle syntyi pysyvää kerrostumaa. Nuohouksella irtoavan tuhkakerrostuman havaittiin sisältävän suuremmat pitoisuudet piitä, alumiinia, natriumia ja kaliumia kuin kattilan läpi jatkuvasti kulkevan lentotuhkan. Tuhkakerrostuma, jota ei nuohouksella saatu poistettua, sisälsi enemmän natriumia, rikkiä, kaliumia ja lyijyä kuin muut tuhkanäytteet. Polttoaineista turpeella oli merkittävin vaikutus likaantumiseen. Turpeen osuuden ollessa suurimmillaan jäivät jättöpinnan tuhkakerrostuman lämpövastukset pienemmiksi kuin muulloin eli lyhytaikaista kerrostumaa syntyi tällöin vähemmän. Pysyvän kerrostuman kasvu hidastui, kun turpeen osuus oli suuri, ja jopa pysähtyi, kun turpeen osuus oli 42-51 %. Prosessiolosuhteista tutkittiin kattilan kuorman vaikutusta likaantumiseen. Havaittiin, että ajettaessa kattilaa isommilla kuormilla, syntyi lyhytaikaista kerrostumaa vähemmän kuin muulloin.

Piikarbidipuolijohdekomponentit tehoelektroniikassa

Piikarbidi (SiC) on tunnettu korkealuokkaisena hioma-aineena ja hiekkapaperin pin-noitteena yli 100 vuoden ajan. Nykyisin ainetta käytetään pääasiassa puolijohteiden raaka-aineena. Piikarbidi on puolijohteena ylivoimainen tavanomaiseen piihin (Si) verrattuna lähes joka suhteessa johtuen sen kiderakenteesta, mutta sen valmistus on osoittautunut erittäin monimutkaiseksi johtuen pääasiassa vaikeudesta kasvattaa riittävän suuria ja laadukkaita SiC-kiteitä. Siksi tehoelektroniikan SiC-puolijohdekomponenttien laajamittaista käyttöä joudutaan yhä odottamaan. Tässä diplomityössä tehdään perusteellinen selvitys, miten piikarbidin valmistuspro-sessit eroavat normaaleista piin valmistusprosesseista, mitä etuja piikarbidin käytöllä saavutetaan ja vastaavasti mitä varjopuolia sillä on. Työssä selvitetään tällä hetkellä markkinoilla olevien SiC-tehopuolijohdekomponenttien ominaisuuksia, ketkä ovat teh-neet tutkimusta alalla, sekä esitetään arvioita SiC-tekniikan tulevaisuuden näkymistä.

Electric field calibration method for scanning electron microscope

This paper proposes a calibration method which can be utilized for the analysis of SEM images. The field of application of the developed method is a calculation of surface potential distribution of biased silicon edgeless detector. The suggested processing of the data collected by SEM consists of several stages and takes into account different aspects affecting the SEM image. The calibration method doesn’t pretend to be precise but at the same time it gives the basics of potential distribution when the different biasing voltages applied to the detector.

Simulations of 3D Stripixel Detectors

Large Hadron Collider (LHC) is the main particle accelerator at CERN. LHC is created with main goal to search elementary particles and help science investigate our universe. Radiation in LHC is caused by charged particles circular acceleration, therefore detectors tracing particles in existed severe conditions during the experiments must be radiation tolerant. Moreover, further upgrade of luminosity (up to 1035 cm-2s-1) requires development of particle detector’s structure. This work is dedicated to show the new type 3D stripixel detector with serious structural improvement. The new type of radiation-hard detector has a three-dimensional (3D) array of the p+ and n+ electrodes that penetrate into the detector bulk. The electrons and holes are then collected at oppositely biased electrodes. Proposed 3D stripixel detector demonstrates that full depletion voltage is lower that that for planar detectors. Low depletion voltage is one of the main advantages because only depleted part of the device is active are. Because of small spacing between electrodes, charge collection distances are smaller which results in high speed of the detector’s response. In this work is also briefly discussed dual-column type detectors, meaning consisting both n+ and p+ type columnar electrodes in its structure, and was declared that dual-column detectors show better electric filed distribution then single sided radiation detectors. The dead space or in other words low electric field region in significantly suppressed. Simulations were carried out by using Atlas device simulation software. As a simulation results in this work are represented the electric field distribution under different bias voltages.

3D Stripixel Detectors Simulation

Solid-state silicon detectors have replaced conventional ones in almost all recent high-energy physics experiments. Pixel silicon sensors don't have any alternative in the area near the interaction point because of their high resolution and fast operation speed. However, present detectors hardly withstand high radiation doses. Forthcoming upgrade of the LHC in 2014 requires development of a new generation of pixel detectors which will be able to operate under ten times increased luminosity. A planar fabrication technique has some physical limitations; an improvement of the radiation hardness will reduce sensitivity of a detector. In that case a 3D pixel detector seems to be the most promising device which can overcome these difficulties. The objective of this work was to model a structure of the 3D stripixel detector and to simulate electrical characteristics of the device. Silvaco Atlas software has been used for these purposes. The structures of single and double sided dual column detectors with active edges were described using special command language. Simulations of these detectors have shown that electric field inside an active area has more uniform distribution in comparison to the planar structure. A smaller interelectrode space leads to a stronger field and also decreases the collection time. This makes the new type of detectors more radiation resistant. Other discovered advantages are the lower full depletion voltage and increased charge collection efficiency. So the 3D stripixel detectors have demonstrated improved characteristics and will be a suitable replacement for the planar ones.

Electric field measurements using scanning electron microscope

The main idea of this diploma work is to study electric field distribution on the micro level. For this purpose a silicon edgeless detector was chosen as the object of investigation and scanning electron microscope as an investigation tool. Silicon edgeless detector is an important part of installation for studying proton-proton interactions in TOTEM experiment at Large Hadron Collider. For measurement of electric field distribution inside scanning electron microscope a voltage contrast method was applied.

Spectroscopic monitoring during laser welding of aluminium alloy

The mechanical properties of aluminium alloys are strongly influenced by the alloying elements and their concentration. In the case of aluminium alloy EN AW-6060 the main alloying elements are magnesium and silicon. The first goal of this thesis was to determine stability, repeatability and sensitivity as figures of merit of the in-situ melt identification technique. In this study the emissions from the laser welding process were monitored with a spectrometer. With the information produced by the spectrometer, quantitative analysis was conducted to determine the figures of merit. The quantitative analysis concentrated on magnesium and aluminium emissions and their relation. The results showed that the stability of absolute intensities was low, but the normalized magnesium emissions were quite stable. The repeatability of monitoring magnesium emissions was high (about 90 %). Sensitivity of the in-situ melt identification technique was also high. As small as 0.5 % change in magnesium content was detected by the spectrometer. The second goal of this study was to determine the loss of mass during deep penetration laser welding. The amount of magnesium in the material was measured before and after laser welding to determine the loss of magnesium. This study was conducted for aluminium alloy with nominal magnesium content of 0-10 % and for standard material EN AW-6060 that was welded with filler wire AlMg5. It was found that while the magnesium concentration in the material changed, the loss of magnesium remained fairly even. Also by feeding filler wire, the behaviour was similar. Thirdly, the reason why silicon had not been detected in the emission spectrum needed to be explained. Literature research showed that the amount of energy required for silicon to excite is considerably higher compared to magnesium. The energy input in the used welding process is insufficient to excite the silicon atoms.

Polymer surface modification by atomic layer deposition

Current industrial atomic layer deposition (ALD) processes are almost wholly confined to glass or silicon substrates. For many industrial applications, deposition on polymer substrates will be necessary. Current deposition processes are also typically carried out at temperatures which are too high for polymers. If deposition temperatures in ALD can be reduced to the level applicable for polymers, it will open new interesting areas and applications for polymeric materials. The properties of polymers can be improved for example by coatings with functional and protective properties. Although the ALD has shown its capability to operate at low temperatures suitable for polymer substrates, there are other issues related to process efficiency and characteristics of different polymers where new knowledge will assist in developing industrially conceivable ALD processes. Lower deposition temperature in ALD generally means longer process times to facilitate the self limiting film growth mode characteristic to ALD. To improve process efficiency more reactive precursors are introduced into the process. For example in ALD oxide processes these can be more reactive oxidizers, such as ozone and oxygen radicals, to substitute the more conventionally used water. Although replacing water in the low temperature ALD with ozone or plasma generated oxygen radicals will enable the process times to be shortened, they may have unwanted effects both on the film growth and structure, and in some cases can form detrimental process conditions for the polymer substrate. Plasma assistance is a very promising approach to improve the process efficiency. The actual design and placement of the plasma source will have an effect on film growth characteristics and film structure that may retard the process efficiency development. Due to the fact that the lifetime of the radicals is limited, it requires the placement of the plasma source near to the film growth region. Conversely this subjects the substrate to exposure byother plasma species and electromagnetic radiation which sets requirements for plasma conditions optimization. In this thesis ALD has been used to modify, activate and functionalize the polymer surfaces for further improvement of polymer performance subject to application. The issues in ALD on polymers, both in thermal and plasma-assisted ALD will be further discussed.

Understanding the in vitro dissolution rate of glasses with respect to future clinical applications

Glass is a unique material with a long history. Several glass products are used daily in our everyday life, often unnoticed. Glass can be found not only in obvious applications such as tableware, windows, and light bulbs, but also in tennis rackets, windmill turbine blades, optical devices, and medical implants. The glasses used at present as implants are inorganic silica-based melt-derived compositions mainly for hard-tissue repair as bone graft substitute in dentistry and orthopedics. The degree of glass reactivity desired varies according to implantation situation and it is vital that the ion release from any glasses used in medical applications is controlled. Understanding the in vitro dissolution rate of glasses provides a first approximation of their behavior in vivo. Specific studies concerning dissolution properties of bioactive glasses have been relatively scarce and mostly concentrated to static condition studies. The motivation behind this work was to develop a simple and accurate method for quantifying the in vitro dissolution rate of highly different types of glass compositions with interest for future clinical applications. By combining information from various experimental conditions, a better knowledge of glass dissolution and the suitability of different glasses for different medical applications can be obtained. Thus, two traditional and one novel approach were utilized in this thesis to study glass dissolution. The chemical durability of silicate glasses was tested in water and TRIS-buffered solution at static and dynamic conditions. The traditional in vitro testing with a TRISbuffered solution under static conditions works well with bioactive or with readily dissolving glasses, and it is easy to follow the ion dissolution reactions. However, in the buffered solution no marked differences between the more durable glasses were observed. The hydrolytic resistance of the glasses was studied using the standard procedure ISO 719. The relative scale given by the standard failed to provide any relevant information when bioactive glasses were studied. However, the clear differences in the hydrolytic resistance values imply that the method could be used as a rapid test to get an overall idea of the biodegradability of glasses. The standard method combined with the ion concentration and pH measurements gives a better estimate of the hydrolytic resistance because of the high silicon amount released from a glass. A sensitive on-line analysis method utilizing inductively coupled plasma optical emission spectrometer and a flow-through micro-volume pH electrode was developed to study the initial dissolution of biocompatible glasses. This approach was found suitable for compositions within a large range of chemical durability. With this approach, the initial dissolution of all ions could be measured simultaneously and quantitatively, which gave a good overall idea of the initial dissolution rates for the individual ions and the dissolution mechanism. These types of results with glass dissolution were presented for the first time during the course of writing this thesis. Based on the initial dissolution patterns obtained with the novel approach using TRIS, the experimental glasses could be divided into four distinct categories. The initial dissolution patterns of glasses correlated well with the anticipated bioactivity. Moreover, the normalized surface-specific mass loss rates and the different in vivo models and the actual in vivo data correlated well. The results suggest that this type of approach can be used for prescreening the suitability of novel glass compositions for future clinical applications. Furthermore, the results shed light on the possible bioactivity of glasses. An additional goal in this thesis was to gain insight into the phase changes occurring during various heat treatments of glasses with three selected compositions. Engineering-type T-T-T curves for glasses 1-98 and 13-93 were stablished. The information gained is essential in manufacturing amorphous porous implants or for drawing of continuous fibers of the glasses. Although both glasses can be hot worked to amorphous products at carefully controlled conditions, 1-98 showed one magnitude greater nucleation and crystal growth rate than 13-93. Thus, 13-93 is better suited than 1-98 for working processes which require long residence times at high temperatures. It was also shown that amorphous and partially crystalline porous implants can be sintered from bioactive glass S53P4. Surface crystallization of S53P4, forming Na2O∙CaO∙2SiO2, was observed to start at 650°C. The secondary crystals of Na2Ca4(PO4)2SiO4, reported for the first time in this thesis, were detected at higher temperatures, from 850°C to 1000°C. The crystal phases formed affected the dissolution behavior of the implants in simulated body fluid. This study opens up new possibilities for using S53P4 to manufacture various structures, while tailoring their bioactivity by controlling the proportions of the different phases. The results obtained in this thesis give valuable additional information and tools to the state of the art for designing glasses with respect to future clinical applications. With the knowledge gained we can identify different dissolution patters and use this information to improve the tuning of glass compositions. In addition, the novel online analysis approach provides an excellent opportunity to further enhance our knowledge of glass behavior in simulated body conditions.

Design and characterization of large area position sensitive radiation detectors

Planar, large area, position sensitive silicon detectors are widely utilized in high energy physics research and in medical, computed tomography (CT). This thesis describes author's research work relating to development of such detector components. The key motivation and objective for the research work has been the development of novel, position sensitive detectors improving the performance of the instruments they are intended for. Silicon strip detectors are the key components of barrel-shaped tracking instruments which are typically the innermost structures of high energy physics experimental stations. Particle colliders such as the former LEP collider or present LHC produce particle collisions and the silicon strip detector based trackers locate the trajectories of particles emanating from such collisions. Medical CT has become a regular part of everyday medical care in all developed countries. CT scanning enables x-ray imaging of all parts of the human body with an outstanding structural resolution and contrast. Brain, chest and abdomen slice images with a resolution of 0.5 mm are possible and latest CT machines are able to image whole human heart between heart beats. The two application areas are presented shortly and the radiation detection properties of planar silicon detectors are discussed. Fabrication methods and preamplifier electronics of the planar detectors are presented. Designs of the developed, large area silicon detectors are presented and measurement results of the key operating parameters are discussed. Static and dynamic performance of the developed silicon strip detectors are shown to be very satisfactory for experimental physics applications. Results relating to the developed, novel CT detector chips are found to be very promising for further development and all key performance goals are met.

Thermal-Aware Networked Many-Core Systems

Advancements in IC processing technology has led to the innovation and growth happening in the consumer electronics sector and the evolution of the IT infrastructure supporting this exponential growth. One of the most difficult obstacles to this growth is the removal of large amount of heatgenerated by the processing and communicating nodes on the system. The scaling down of technology and the increase in power density is posing a direct and consequential effect on the rise in temperature. This has resulted in the increase in cooling budgets, and affects both the life-time reliability and performance of the system. Hence, reducing on-chip temperatures has become a major design concern for modern microprocessors. This dissertation addresses the thermal challenges at different levels for both 2D planer and 3D stacked systems. It proposes a self-timed thermal monitoring strategy based on the liberal use of on-chip thermal sensors. This makes use of noise variation tolerant and leakage current based thermal sensing for monitoring purposes. In order to study thermal management issues from early design stages, accurate thermal modeling and analysis at design time is essential. In this regard, spatial temperature profile of the global Cu nanowire for on-chip interconnects has been analyzed. It presents a 3D thermal model of a multicore system in order to investigate the effects of hotspots and the placement of silicon die layers, on the thermal performance of a modern ip-chip package. For a 3D stacked system, the primary design goal is to maximise the performance within the given power and thermal envelopes. Hence, a thermally efficient routing strategy for 3D NoC-Bus hybrid architectures has been proposed to mitigate on-chip temperatures by herding most of the switching activity to the die which is closer to heat sink. Finally, an exploration of various thermal-aware placement approaches for both the 2D and 3D stacked systems has been presented. Various thermal models have been developed and thermal control metrics have been extracted. An efficient thermal-aware application mapping algorithm for a 2D NoC has been presented. It has been shown that the proposed mapping algorithm reduces the effective area reeling under high temperatures when compared to the state of the art.

Simulation of new p-type pixel strip detector with enhanced multiplication effect

This Master’s Thesis is dedicated to the simulation of new p-type pixel strip detector with enhanced multiplication effect. It is done for high-energy physics experiments upgrade such as Super Large Hadron Collider especially for Compact Muon Solenoid particle track silicon detectors. These detectors are used in very harsh radiation environment and should have good radiation hardness. The device engineering technology for developing more radiation hard particle detectors is used for minimizing the radiation degradation. New detector structure with enhanced multiplication effect is proposed in this work. There are studies of electric field and electric charge distribution of conventional and new p-type detector under reverse voltage bias and irradiation. Finally, the dependence of the anode current from the applied cathode reverse voltage bias under irradiation is obtained in this Thesis. For simulation Silvaco Technology Computer Aided Design software was used. Athena was used for creation of doping profiles and device structures and Atlas was used for getting electrical characteristics of the studied devices. The program codes for this software are represented in Appendixes.

Transient current technique simulation of semiconductor detectors

Nowadays advanced simulation technologies of semiconductor devices occupies an important place in microelectronics production process. Simulation helps to understand devices internal processes physics, detect new effects and find directions for optimization. Computer calculation reduces manufacturing costs and time. Modern simulation suits such as Silcaco TCAD allow simulating not only individual semiconductor structures, but also these structures in the circuit. For that purpose TCAD include MixedMode tool. That tool can simulate circuits using compact circuit models including semiconductor structures with their physical models. In this work, MixedMode is used for simulating transient current technique setup, which include detector and supporting electrical circuit. This technique was developed by RD39 collaboration project for investigation radiation detectors radiation hard properties.

Power semiconductor nonlinearities in active du/dt output filtering

This doctoral thesis introduces an improved control principle for active du/dt output filtering in variable-speed AC drives, together with performance comparisons with previous filtering methods. The effects of power semiconductor nonlinearities on the output filtering performance are investigated. The nonlinearities include the timing deviation and the voltage pulse waveform distortion in the variable-speed AC drive output bridge. Active du/dt output filtering (ADUDT) is a method to mitigate motor overvoltages in variable-speed AC drives with long motor cables. It is a quite recent addition to the du/dt reduction methods available. This thesis improves on the existing control method for the filter, and concentrates on the lowvoltage (below 1 kV AC) two-level voltage-source inverter implementation of the method. The ADUDT uses narrow voltage pulses having a duration in the order of a microsecond from an IGBT (insulated gate bipolar transistor) inverter to control the output voltage of a tuned LC filter circuit. The filter output voltage has thus increased slope transition times at the rising and falling edges, with an opportunity of no overshoot. The effect of the longer slope transition times is a reduction in the du/dt of the voltage fed to the motor cable. Lower du/dt values result in a reduction in the overvoltage effects on the motor terminals. Compared with traditional output filtering methods to accomplish this task, the active du/dt filtering provides lower inductance values and a smaller physical size of the filter itself. The filter circuit weight can also be reduced. However, the power semiconductor nonlinearities skew the filter control pulse pattern, resulting in control deviation. This deviation introduces unwanted overshoot and resonance in the filter. The controlmethod proposed in this thesis is able to directly compensate for the dead time-induced zero-current clamping (ZCC) effect in the pulse pattern. It gives more flexibility to the pattern structure, which could help in the timing deviation compensation design. Previous studies have shown that when a motor load current flows in the filter circuit and the inverter, the phase leg blanking times distort the voltage pulse sequence fed to the filter input. These blanking times are caused by excessively large dead time values between the IGBT control pulses. Moreover, the various switching timing distortions, present in realworld electronics when operating with a microsecond timescale, bring additional skew to the control. Left uncompensated, this results in distortion of the filter input voltage and a filter self-induced overvoltage in the form of an overshoot. This overshoot adds to the voltage appearing at the motor terminals, thus increasing the transient voltage amplitude at the motor. This doctoral thesis investigates the magnitude of such timing deviation effects. If the motor load current is left uncompensated in the control, the filter output voltage can overshoot up to double the input voltage amplitude. IGBT nonlinearities were observed to cause a smaller overshoot, in the order of 30%. This thesis introduces an improved ADUDT control method that is able to compensate for phase leg blanking times, giving flexibility to the pulse pattern structure and dead times. The control method is still sensitive to timing deviations, and their effect is investigated. A simple approach of using a fixed delay compensation value was tried in the test setup measurements. The ADUDT method with the new control algorithm was found to work in an actual motor drive application. Judging by the simulation results, with the delay compensation, the method should ultimately enable an output voltage performance and a du/dt reduction that are free from residual overshoot effects. The proposed control algorithm is not strictly required for successful ADUDT operation: It is possible to precalculate the pulse patterns by iteration and then for instance store them into a look-up table inside the control electronics. Rather, the newly developed control method is a mathematical tool for solving the ADUDT control pulses. It does not contain the timing deviation compensation (from the logic-level command to the phase leg output voltage), and as such is not able to remove the timing deviation effects that cause error and overshoot in the filter. When the timing deviation compensation has to be tuned-in in the control pattern, the precalculated iteration method could prove simpler and equally good (or even better) compared with the mathematical solution with a separate timing compensation module. One of the key findings in this thesis is the conclusion that the correctness of the pulse pattern structure, in the sense of ZCC and predicted pulse timings, cannot be separated from the timing deviations. The usefulness of the correctly calculated pattern is reduced by the voltage edge timing errors. The doctoral thesis provides an introductory background chapter on variable-speed AC drives and the problem of motor overvoltages and takes a look at traditional solutions for overvoltage mitigation. Previous results related to the active du/dt filtering are discussed. The basic operation principle and design of the filter have been studied previously. The effect of load current in the filter and the basic idea of compensation have been presented in the past. However, there was no direct way of including the dead time in the control (except for solving the pulse pattern manually by iteration), and the magnitude of nonlinearity effects had not been investigated. The enhanced control principle with the dead time handling capability and a case study of the test setup timing deviations are the main contributions of this doctoral thesis. The simulation and experimental setup results show that the proposed control method can be used in an actual drive. Loss measurements and a comparison of active du/dt output filtering with traditional output filtering methods are also presented in the work. Two different ADUDT filter designs are included, with ferrite core and air core inductors. Other filters included in the tests were a passive du/dtfilter and a passive sine filter. The loss measurements incorporated a silicon carbide diode-equipped IGBT module, and the results show lower losses with these new device technologies. The new control principle was measured in a 43 A load current motor drive system and was able to bring the filter output peak voltage from 980 V (the previous control principle) down to 680 V in a 540 V average DC link voltage variable-speed drive. A 200 m motor cable was used, and the filter losses for the active du/dt methods were 111W–126 W versus 184 W for the passive du/dt. In terms of inverter and filter losses, the active du/dt filtering method had a 1.82-fold increase in losses compared with an all-passive traditional du/dt output filter. The filter mass with the active du/dt method was 17% (2.4 kg, air-core inductors) compared with 14 kg of the passive du/dt method filter. Silicon carbide freewheeling diodes were found to reduce the inverter losses in the active du/dt filtering by 18% compared with the same IGBT module with silicon diodes. For a 200 m cable length, the average peak voltage at the motor terminals was 1050 V with no filter, 960 V for the all-passive du/dt filter, and 700 V for the active du/dt filtering applying the new control principle.