| 21. |
- Andersson, Henrik, 1975-
(författare)
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Position Sensitive Detectors : Device Technology and Applications in Spectroscopy
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis deals with the development, processing and characterization of position sensitive detectors and, in addition, to the development of compact and cost effective spectrometers. Position sensitive detectors are used to measure, with great accuracy and speed, the position of a light spot incident on the surface. Their main use is for triangulation, displacement and vibration measurements. A type of position sensitive detector based on the MOS principle and using optically transparent indium tin oxide as a gate contact has been developed. This type of detector utilizes the MOS principle where an induced channel forms beneath the gate oxide in the surface of the Silicon substrate. One and two dimensional detectors have both been fabricated and characterized. The first measurements showed that the linearity did not fulfil expectations and it was suspected that stress induced by the gate contact could be the reason for the seemingly high nonlinearity. Further investigations into both the p-n junction and the MOS type position sensitive detectors lead to the conclusion that the indium tin oxide gate is responsible for inducing a substantial stress in the surface of the detector, thus giving rise to increased position nonlinearity. The heat treatment step which was conducted was determined to be critical as either a too short or too long heat treatment resulted in stress in the gate and channel leading to position nonlinearity. If a correctly timed heat treatment is performed then the detector’s linearity is in parity with the best commercial position sensitive detectors. In addition, the development of very small, compact and cost effective spectrometers has been performed with the aim of constructing devices for use in the process industry. The development of a wedge shaped array of Fabry-Perot interferometers that can be mounted directly on top of a detector makes it possible to construct a very compact spectrometer using the minimum amount of optics. This wedge interferometer has been evaluated by means of array pixel detectors and position sensitive detectors for both the infrared and the visible wavelength ranges. When used with a position sensitive detector it is necessary to use a slit to record the intensity of the interferogram for many points over the detector, equivalent to pixels on an array detector. Usually the use of moving parts in a spectrometer will impose the use of high precision scanning mechanisms and calibration. By using a position sensitive detector for the interferogram readout both the position and the intensity are known for every measurement point and thus the demands placed on the scanning system are minimized.
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| 22. |
- Andreassen Devik, Siri
(författare)
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Hjemmesykepleie til eldre som bor på bygda med uhelbredelig kreft
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The need to deliver high-quality palliative homecare has been underscored in current professional guidelines and demands for efficacy, as well as in the preferences of patients and their families. Indeed, demographic changes and an increased risk of cancer among older people pose challenges to the home healthcare settings in Norway and the rest of the world. Yet, little is known about how older persons experience living with incurable cancer and how palliative home nursing care may increase their quality of life. Moreover, few studies have focused on rural contexts or explored such settings can influence the delivery and outcome of care. In rural contexts, long distances and limited health-related human resources challenge the provision of specialised services, and palliative patients living in rural municipalities most often receive services from district nurses without special training in oncological or palliative care. The aim of this thesis was thus to explore experiences with, and meanings of, rural home nursing care among older persons living with incurable cancer. The thesis consists of five studies, all with qualitative designs, and performed in rural municipalities.Study I was designed as a case study involving individual interviews and observations to explore how older persons diagnosed with incurable cancer and living alone have experienced daily life while commuting for policlinic palliative chemotherapy. By extension, the aim of Study II, conducted as a secondary analysis of material collected in study I, was to illuminate and interpret the meanings of the lived experiences of the participants in that study. By contrast, Study III used individual interviews to illuminate and interpret the meaning of the lived experience of older persons with incurable cancer, yet who have received home nursing care. Meanwhile, Study IV entailed individual interviews with nurses working in home nursing care. Its aim was to illuminate and interpret the meaning of nurses' lived experiences among severely ill patients in their homes. Lastly, Study V involved individual interviews with bereaved family members; its aim was to explore their perceptions of suffering in older persons receiving palliative home nursing care during their final phase of life. The findings of Study I showed that older persons interviewed hovered between hope and fear, experienced stressful commutes, and were constantly exhausted. Experiences with long, tiring taxi trips, of having few supportive people nearby, and of being offered hardly any local healthcare services made these persons highly vulnerable. Nevertheless, their demands were few, and they rarely complained. The findings of Study II showed a complex, yet comprehensive situation in which physical symptoms and emotions had become entangled. Four themes were found: enduring by keeping hope alive, becoming aware of being one one's own, living up to expectations of being a good patient, and being at risk of losing identity and value. Suffering related to care, or the lack therefore, was the most striking discovery, and the older persons seemed to endure by keeping hope alive. Besides hoping for survival, their hopes also included a desire to be recognised and treated with respect, though such often seemed to go unnoticed. The findings of Study III revealed three themes: being content with what one gets, falling into place, and losing one's place. The phrase picking up the pieces was found useful for summing up the meaning of one's lived experience. In that sense, the three themes referred to how the pieces symbolized the remaining parts of life or services available in their environment and how the older persons might see themselves as pieces in a puzzle. Participants exhibited strong place attachment, involving physical insideness, social insideness, and autobiographical insideness, which suggested that the rural context might provide and advantageous healthcare environment. Interestingly, nurses' personal engagement and willingness to be involved in caring relationship appeared to be more important than any special competence or technical skills. The findings of Study IV showed that patients' expressions left impressions that caused emotional waves in the nurses. Four themes were found: being open for the presence of the Other, being satisfied, being frustrated, and being ambivalent. Understanding and balancing this emotional dimension in care seemed to cause confusion and distress for the nurses, and realizing how their feelings might prompt either generosity or aloofness towards the patient was upsetting. Thatinterpretation suggested confusion regarding what it means to be a professional nurse.Lastly, the findings of Study V showed that bereaved family members perceived suffering related to the illness, to the care, and to the life of their ill relatives during their final phase of life. Well-being emerged as having significant, contrasting elements. Well-being related to other people, to the home, and to activity, in all of which the essence referred to a state of dwelling-mobility. The findings suggested that nurses in this context need to seek out patients' and their families members' experiences with comfort and with disturbance. Nursing and palliative care that become purely disease- and symptom-focused can end with all parties' giving up and divert attention from social and cultural factors that may contribute to well-being when cure is not the goal.The findings of this thesis could alter some current knowledge in the field. From a patient perspective, the rural context is not necessarily disadvantaged, care is not necessarily caring, and the alleviation of suffering and cultivation of wellbeing are not necessarily two sides of the same coin. Home nursing care is often seen as a precondition for staying at home. Working in patients' homes allows nurses to witness and become involved in each patient's unique situation. However, impressions of patients' expressions awake feelings in nurses that have the power to bring about caring actions. At the same time, the fear of being unprofessional or unable to deliver proper care bothers nurses and might threaten the closeness that patients desire. Home nursing is care organized in a system in which services are predefined, apportioned, and bound to specific procedures, and the holistic ideals of the palliative care philosophy are often not within the framework of the system in which district nurses work.
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| 23. |
- Andres, Britta, 1986-
(författare)
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Low-Cost, Environmentally Friendly Electric Double-Layer Capacitors : Concept, Materials and Production
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Today’s society is currently performing an exit from fossilfuel energy sources. The change to sustainable alternativesrequires inexpensive and environmentally friendly energy storagedevices. However, most current devices contain expensive,rare or toxic materials. These materials must be replaced bylow-cost, abundant, nontoxic components.In this thesis, I suggest the production of paper-based electricdouble-layer capacitors (EDLCs) to meet the demand oflow-cost energy storage devices that provide high power density.To fulfill the requirements of sustainable and environmentallyfriendly devices, production of EDLCs that consist of paper,graphite and saltwater is proposed. Paper can be used as aseparator between the electrodes and as a substrate for theelectrodes. Graphite is suited for use as an active material in theelectrodes, and saltwater can be employed as an electrolyte.Westudied and developed different methods for the productionof nanographite and graphene from graphite. Composites containingthese materials and similar advanced carbon materialshave been tested as electrode materials in EDLCs. I suggest theuse of cellulose nanofibers (CNFs) or microfibrillated cellulose(MFC) as a binder in the electrodes. In addition to improvedmechanical stability, the nanocellulose improved the stabilityof graphite dispersions and the electrical performance of theelectrodes. The influence of the cellulose quality on the electricalproperties of the electrodes and EDLCs was investigated.The results showed that the finest nanocellulose quality is notthe best choice for EDLC electrodes; MFC is recommended forthis application instead. The results also demonstrated thatthe capacitance of EDLCs can be increased if the electrodemasses are adjusted according to the size of the electrolyte ions.Moreover, we investigated the issue of high contact resistancesat the interface between porous carbon electrodes and metalcurrent collectors. To reduce the contact resistance, graphitefoil can be used as a current collector instead of metal foils.Using the suggested low-cost materials, production methodsand conceptual improvements, it is possible to reduce the material costs by more than 90% in comparison with commercialunits. This confirms that paper-based EDLCs are apromising alternative to conventional EDLCs. Our findings andadditional research can be expected to substantially supportthe design and commercialization of sustainable EDLCs andother green energy technologies.
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| 24. |
- Andresen, Edith
(författare)
-
Dressed for success : designing and managing regional strategic networks
- 2011
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Inter-organizational network initiatives such as regional strategic networks (RSNs) are often used by firms and public agencies to support regional development and competitiveness. RSNs are designed networks managed by a hub and financed by public or private means. RSN management is complex as members are autonomous and initially often loosely connected. The effects of RSNs on regional development are disputed as engineered relationship development may interfere with ongoing business relationships. Despite this, vast public funds are being invested in collaborative initiatives. Identifying factors affecting RSN performance will provide a better basis for evaluating and managing such initiatives.Based on concepts such as actors, resources, and activities findings are reported from longitudinal case-studies built on interviews with 68 members and hubs in four RSNs. Data were also collected through participant observation, conversations, archival data and emails. Findings indicate that factors such as evaluation criteria, member composition, relationships, location, goals, the hub, physical and human resources, knowledge sharing and development, resources, policies and norms, social activities, and communication exert an impact on entrepreneurship and cooperation.The first paper focuses on factors such as actor composition, actor goals, number of actors, and activities facilitating relationship development and commitment. The second paper identifies a framework of seven tasks to be performed by the hub. The effects on development of preferences and atmosphere are dealt with in the third paper. Effects of cooperation between public/private sector and universities are addressed in the fourth paper, and entrepreneurial processes in network contexts are analyzed in the fifth one.The important management role of the hub is emphasized as is carefully considered member composition. Relationships and commitment are found to be crucial. These factors are not covered by national and regional performance criteria. They merit a place of their own.
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| 25. |
- Aranda, Jesus Javier Lechuga
(författare)
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Towards Self-Powered Devices Via Pressure Fluctuation Energy Harvesters
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The growing interest in the Internet of Things has created a need for wireless sensing systems for industrial and consumer applications. In hydraulic systems, a widely used method of power transmission in industry, wireless condition monitoring can lead to reduced maintenance costs and increase the capacity for sensor deployment. A major problem with the adoption of wireless sensors is the battery dependence of current technologies. Energy harvesting from pressure fluctuations in hydraulic systems can serve as an alternative power supply and enable self-powered devices. Energy harvesting from pressure fluctuations is the process of converting small pressure fluctuations in hydraulic fluid into a regulated energy supply to power low power electronics. Previous studies have shown the feasibility of pressure fluctuation harvesting. However, for the development of self-powered sensor systems, the methods and techniques for converting pressure fluctuations into electrical energy should be further investigated.This thesis explores the methods, limitations, opportunities and trade-offs involved in the development of pressure fluctuation energy harvesters in the context of self-powered wireless devices. The focus is on exploring and characterizing the various mechanisms required to convert pressure fluctuations into electrical energy. In this work, an energy harvesting device consisting of a fluid-to-mechanical interface, an acoustic resonator, a piezoelectric stack, and an interface circuit is proposed and evaluated. Simulations and experimental analysis were used to analyse these different components for excitation relevant to hydraulic motors.The results of this work provide new insights into the development of power supplies for self-powered sensors for hydraulic systems using pressure fluctuation energy harvesters. It is shown that with the introduction of the space coiling resonator for pressure fluctuation amplification and a detailed analysis of the fluid interface and power conditioning circuits, the understanding of the design and optimization of efficient pressure fluctuation energy harvesters is further advanced.
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| 26. |
- Aronsson, K. Andreas
(författare)
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Effects of wood ash on freshwater organisms and aquatic forest ecosystems
- 2007
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Wood ash application (WAA) has been recommended mainly for two reasons; i) to avoid depletion of minerals in the soil due to whole tree harvest in the forestry and ii) to mitigate harmful effects of acidification of soil and surface waters. In conclusion, the effects on terrestrial ecosystems and, especially, tree growth, can be attributed to the properties of the ash, the dose applied and the specific site at which the ash is applied. The research conducted on the effects of WAA on limnological ecosystems is very limited, and the major purpose of the present thesis was to gain knowledge of the effects of wood ash to different freshwater organisms, and the more comprehensive, limnological effects of WAA in the first stream in Bispgården, Sweden. Effects of wood ash solutions on the unicellular alga Euglena gracilis Klebs, the amphipod Gammarus pulex L., and the moss Fontinalis antipyretica Hedw. were investigated under laboratory conditions. Common in all three species was the decline in performance (growth/velocity/respiration/oxygen evolution) when the concentration of wood ash exceeded 5 g/l and no adjustment of pH was done (alkaline solution). In contrast, different movement parameters (motility, upwards swimming and velocity) in E. gracilis (neutral conditions), and increased growth of F. antipyretica with increased concentrations of wood ash indicated that nutrients in the ash was bioavailable for these organisms. There was no evidence of toxic effects on the organisms from metals or other compounds as a result from exposure to wood ash solutions in the present studies. The field study was conducted in a forest area close to Bispgården, about 100 km NW from Sundsvall, Sweden. The catchment area (50 ha) of the stream Fanbergsbäcken was treated with wood ash in September of 2004 (3,000 kg/ha;selfhardened crush-ash). In general, both biological (diatoms) and chemical (pH, alkalinity, and aluminum (Al) measurements) indicators have shown no significant effect on acidification parameters from the addition of wood ash. There was, however, evidence of an increased pH during spring flood, accompanied with a decrease in the frequency of low pH values (<5.6) during spring flood. In addition to this, alkalinity was significantly higher in the period 2005-2006, compared to that of 2003. High concentrations of toxic forms of Al repeatedly occured in the stream Fanbergsbäcken, and the WAA did not affect the frequencies of high concentrations of toxic Al forms (<50 μg/l). Both the moss F. antipyretica and the leaves from Alnus incana displayed increased potassium (K) concentrations, although other nutrients did not increase from WAA. In conclusion, no evidence of WAA being effective in restoring or improving the ecological status of freshwater environments has been established, either in the literature or in the present field study. On the other hand, there were no indications of harmful effects due to WAA, either. However, we still do not know the effects of wood ash on several organisms (predominantly invertebrates) inhabiting small ponds and other, temporary or permanent, freshwater ecosystems. In the context of WAA, these environments and organisms have not attended any attention in the research published to date, and future studies are strongly encouraged.
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| 27. |
- Arvidson, Catarina, 1959-
(författare)
-
Genuspedagogers berättelser om makt och kontroll
- 2014
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this thesis 14 gender pedagogues’ stories about power and control are described and analysed. Here the term gender pedagogue refers to educators who have participated in further training in gender and gender equality studies. The training programme was the result of an initiative taken by the former Social Democratic government. The intention of the government was that those who participated in the training programme would then work as resource persons in the work for gender equality in preschools and schools (Frånberg, 2010; Regeringen, 2001a, 2001b; Wahlgren, 2009). The purpose of this study is to describe and analyse the gender pedagogues’ access to power and control in work for change. The theoretical framework chosen for the study consists of Basil Bernsteins concepts classification and framing (Bernstein, 1977, 2000) and Hildur Ve’s (1999a, 1999b) use of the concepts technical limited rationality and care work rationality. The empirical evidence is based on observations in a seminar series on gender issues and semi-structured interviews. The results of the interviews are presented as stories which have been created in the interplay between the gender pedagogues and the interviewer. One conclusion that can be drawn from the stories is that power relations and gender patterns on many different levels influenced the possibilities of the gender pedagogues for power and control. Power and control in the relation between technical limited rationality and care work rationality is expressed in different ways. It is seen in the possibilities and descriptions of resistance and difficulties. Resistance and difficulties depended, according to the gender pedagogues, on the differences between their own view of knowledge and that of others. If gender and gender equality was not considered to be an important area of knowledge, possibilities for power and control decreased.
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| 28. |
- Ashraf, Shakeel, 1984-
(författare)
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Thermal detector with integrated absorber structure for mid-IR gas detection
- 2018
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Measurement of the concentration of greenhouse gases, such as carbon dioxide(CO 2 ) and methane (CH 4 ), in the atmosphere has received significant attention in the last few decades. This work focusses on the development of high-performance thermopile detectors for use with the non-dispersive infrared (NDIR) measurements of such gases. The performance of the thermopile detectors could effectively be increased by selecting membrane materials with a low thermal conductivity value and an efficient infrared (IR) absorbing material and by selecting the materials with high Seebeck coefficient values. Graphite black paint can be used as a radiation absorber, as it has high absorption (80—93%) for a wide spectral range (2.5 μm — 20 μm). By using spray paint or a paint brush, the application of the absorber is simple and fast. However, the control over the processing process suffers with these simple methods. The thermal capacitance of the detector will rapidly increase due to uneven distribution and unknown thickness of the absorber, although the response of the thermopile detector will be maximum due to high absorption; however, the response time (τ th )for the detector will be longer.In order to improve the performance, IR absorbers have been designed to utilise the membrane (SU-8 epoxy) of the detector as an active part of the IR absorber. This utilisation of the SU-8 epoxy membrane will result in a maximum detector sensitivity and a minimum increase in both the thermal capacitance and thermal conductance of the thermopile detector. Absorber structures, based on SU-8 epoxy, with a narrow absorption band at 4.26 µm and a wider multi-layered absorption band at 3-6 µm, were designed, simulated, and fabricated, and their integration into the membrane of thermopile detectors have been presented. The response of the thermopile detector could also be increased by using materials with high Seebeck coefficient [1] values such as semiconductor materials, as they have higher Seebeckvalues compared to the metals. In the thesis, molybdenum disulfide (MoS 2 ) flakes were characterised, and Seebeck values were estimated through a measurement setup as a function of temperature difference (ΔT). The fabricated thermopile detectors were characterised, and the response time(τ th ) of a thermocouple with a multi-layered absorber structure has been estimated to be 21 ms. The detector has shown high responsivity value in the wavelength range of 3 µm – 4.5 µm, which is used for CO 2 and CH 4 detection. The thermopile detector was evaluated for CO 2 gas through a long-path-length NDIR platform. The results show that the evaluated thermopile could be used for the measurement of gas concentration down to levels of a few parts per million (ppm) by using the long-path-length NDIR platform.
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| 29. |
- Bader, Sebastian
(författare)
-
On the lifetime and usability of environmental monitoring wireless sensor networks
- 2013
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Wireless sensor networks have been demonstrated, at an early stage in their development, to be a useful measurement technology for environmental monitoring applications. Based on their independence from existing infrastructures, wireless sensor networks can be deployed in virtually any location and provide sensor samples in a spatial and temporal resolution, which otherwise would only be achievable at high cost or involve significant work by humans.The feasibility of the usage of wireless sensor networks in real-world applications, however, is only maintained if certain technological challenges are overcome. Amongst these challenges, are the limited lifetime of the distributed sensor nodes, and user interfaces, which allow for the technology to be utilized in an efficient manner. Contributions to the solution of these challenges have been the objective of this thesis.After an analysis of the contributions wireless sensor networks can provideto the application domain of environmental monitoring, and the introductionto the restrictions, which are posed by a limited operational lifetime and lowsystem usability, these issues are addressed at the system level of sensor nodedevices.The lifetime of sensor nodes, which is closely linked to the lifetime of thecomplete wireless sensor network, is addressed with regards to the energyefficiency of nodes, as well as the utilization of solar energy harvesting inorder to increase the available energy resources. With respect to energyefficiency, an analysis has been performed of the contributions to the energyconsumption of environmental monitoring sensor nodes, which leads to thedesire to minimize the nodes' duty cycles and quiescent currents. A sensornode design is presented, which features energy efficiency as a key attribute by utilizingmodern semiconductor architectures. Moreover, an argument for the usage of synchronization-based, contention-free communication is madein order to reduce active communication periods and, thus, the duty cycleof a sensor node. A synchronization method with its focus on low protocoloverhead is introduced as a basis for such communication forms. After an initial feasibility study in relation to using battery-less solar energyharvesting architectures in locations with limited solar irradiation, multiplearchitectural implementations are analyzed in a comparative manner.Among these comparisons is an analysis of short-termenergy storage devices in the form of double-layer capacitors and thin-film batteries, which provide prolonged component lifetimes than those for conventional secondary batteries, but which can only buffer for short periods of time due to their limited energy capacity. In order to be able to dimension such energy harvesting systems with respect to the individual application constraints at hand, state of charge simulations are proposed. Amethod for such simulations is presented and demonstrated for the implementation of an energy harvester model on a component basis. While the modeling in this manner is time consuming, the model can predict the state of charge of the energy buffer in the architecture with a high level of accuracy. Finally, a method for the systematic evaluation of solar energy harvesting architectures is presented. The presented method can be summarized as a solar energy harvesting testbed, which utilizes configurable energy harvesting circuits in order to create a deploy-once-test-many type of system. The output results of this testbed can significantly improvethe efficiency of architecture comparisons and system modeling.Contributions to the improvement of the usability of wireless sensor nodesare made on two separate levels, namely, developer usability and end userusability. A method for the programming of sensor nodes based on hierarchical finite state machines is presented, which improves the usability of software development by creating familiarity for technically experiencedusers. Moreover, the utilization of finite state machine principles allowsfor the software to be developed in a systematic andmodular manner. Asimplemented applications typically require to be verified, which, in the environmental monitoring domain, usually results in outdoor deployments,usability considerations for sensor nodes are presented, which can simplifythis process. Special attention has been paid in order for these improvements to be achieved with low overheads. While software development is a familiar concept for most system developers, this is not the case for the end users of these systems, who are typically domain experts. In order to allow for wireless sensor nodes to be operatedby domain experts, a method for the configuration of sensor nodes has been proposed.The method uses a combination of graphical specification of the node behavior and a configurable sensor node. Theevaluation of this method, which has been based on a proof-of-concept implementation, demonstrated that the performance can remain high, while end users, without technical experience, are enabled to configure sensor nodes without prior training.In summary, the contributions, presented in this thesis, address systemlifetime and usability with regards to the sensor node level. The results haveled to the implementation of an energy efficient sensor node, which allows for the operation frombattery-less solar energy harvesting sources. Furthermore, support tools for the implementation of these nodes, both on the hardware and software level, have been proposed.
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| 30. |
- Bakar, Muhammad Abu, 1969-
(författare)
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Wide Range Isolated Power Converters
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Power electronics technology is rapidly growing in most industrialapplications. There is an increasing demand for efficient and low profilepower converters in the industry like automotive, power grids, renewableenergy systems, electric rail systems, home appliances, and informationtechnology. In some applications, there is an increasing demand for powerconverters showing a stable performance over a wide variation in inputvoltage, whereas in others the demand is for converters showing a stableperformance over a wide variation of output voltage. In this regard, not somuch work has been done to combine both requirements into one solution;this is the primary focus of the dissertation. It presents a unique solution tothe industry, which addresses both requirements. The technique can beapplied in a one size fits all solution which not only extends the range of theline voltage and the output voltage but also provides the flexibility to adjustthe required set of line/output voltage. The variation in line voltage severelydegrades the performance of power converters because of the extendedfreewheeling interval, more circulating current, narrow range of zero voltageswitching and increased EMI. To overcome this, the converter consists of tworeconfigurable modes on the input side that can be configured following thevariation in line voltage to maintain a stable performance. In addition, itproposes three reconfigurable steps for the output voltage, which can be usedto adjust the output voltage from base level X to 2X and 4X in discrete stepsand/or from X - 4X volt while showing stable performance. This makes theproposal a 2x3 reconfigurable modes power converter, which means that thegain of the proposed converter can be raised to 4 or 8. Furthermore, theflexibility in the reconfigurable structure simplifies the implementation of theproposed single solution in a range of applications. Each concept proposed inthe thesis is verified analytically, experimentally and modelling it into aSPICE simulation. Then the whole concept is confined into a single entity,which is applied in an example application of a phase shifted full bridgeconverter. The full converter is characterized for input voltage 100-400Vdc, theoutput voltage 24-96Vdc, and up to the load power of 1kW.
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