Load identification of different Halbach-array topologies on permanent magnet synchronous generators using the coupled field-circuit FE methodology

In this paper, the influence of gap consideration on load identification under various Halbach-array-based topologies (HABOs) is investigated while the system is on-duty. The load characteristics of a radial flux generator with closed-slots and the exterior rotor topology is discussed, where the effect of eddy-currents are observed. This comparative study deals with the consideration of the combined moment of inertia calculation that demonstrates how electromagnetic-based post processing calculations are estimated without the aid of nominal machine parameter values. The analysis was performed using a 2-D finite-element simulation of different HABOs with the gap consideration between the segments. Additionally, a comprehensive comparison with no gap is considered. Also, the dynamic analysis using an uncontrolled conventional rectifier model is used to derive effected key output parameters such as torque, output power, power factor, and line-to-line voltage. The major objective of the study is to determine corresponding load results in order to employ the most suitable and capable magnetization topology from the load perspective in the PM synchronous generator (PMSGs). Accordingly, the maximum power (MP) point was carried out to maximize the output DC power. With respect to the combined moment of inertia estimation, the load parameter estimation is verified experimentally on a surface-mounted PMSG using different magnetization topologies. Furthermore, commercial and environmental issues of the project are considered to reduce CO2 emissions as part of green power generation development.Peer ReviewedPostprint (author's final draft

Applications of Solar Thermal Technology for Plastic Waste Management in Developing Communities

As the plastic industry continues to grow globally, with plastic materials contained in a vast quantity of consumer products, the management of the resultant waste has become one of the greatest challenges of our time. Greater than 8 million metric tons of plastics were estimated to enter the world’s oceans as of 2010, with an even larger amount remaining on land. The associated ecological and health effects of plastic waste disposal are many, and existing solutions can only tackle small portions of the waste.China and Indonesia top the current list of contributors to ocean contamination with plastic waste, which is dominated by Asian countries. China in particular is positioned as the world’s leader in plastic production. The waste management scenarios of these countries and associated energy outlooks are discussed, where the plastic waste of the islands of Indonesia is mostly a result of residential, not industrial activities. These calculations are projected to 2025 with recent values of population growth, as an update to previous literature, with Vietnam now expected to supersede both Indonesia and the Philippines. Given the available solar resource in the top coastal plastic waste producing nations, many of which lie within close proximity to the equator, the feasibility of applying solar thermal power for the melting of plastic waste is examined. Melting points of common plastics are typically below 200°C, and thus lie within the range of low-temperature parabolic solar thermal systems.A prototype non-evacuated tube parabolic trough was constructed following methodologies for accessible technologies for the developing world. Tests in Stockholm, Sweden demonstrated its ability to partially melt waste ABS from a 3D printer. Internal temperatures up to 211°C were recorded in further tests in Ioannina, Greece, where HDPE, LDPE, and PP were successfully melted along with waste household items. Heat loss was calculated as well as associated internal dynamics, examining the interaction of ambient conditions with the chosen design parameters. Additional testing is needed to constrain surface heat loss for higher temperature applications such as plastics like PET that melt above the exhibited range. Future refinements to the design are discussed as well as the role micro-projects have in the reduction of plastic waste at its source within developing countries.Plastindustrin fortsätter att växa årligen, med plast som finns i en stor mängd konsumentprodukter, har hanteringen av det resulterande avfallet blivit en av de största utmaningarna i vår tid. Mer än 8 miljoner ton av plast beräknades nå världens hav varje år enligt en studie ifrån 2010, med en ännu större mängd kvar på land. De därmed sammanhängande ekologiska och hälsopåverkande effekterna av att leva med en sådan mängd plastavfall är många, och befintliga lösningar kan bara hantera små delar av avfallet.Kina och Indonesien leder nuvarande lista över bidragsgivare till havsplast, som domineras av asiatiska länder. Kina är i synnerhet världsledande inom plastproduktion. Avfallshanteringsscenarierna i dessa länder och därtill hörande energiutsikter diskuteras, där plastavfallet på Indonesiens öar främst är ett resultat av bostads-, och inte industriell verksamhet. Dessa beräkningar projiceras till 2025 med de senaste värdena av befolkningstillväxt, som en uppdatering till tidigare litteratur, där Vietnam nu förväntas överträffa både Indonesien och Filippinerna. Med tanke på den tillgängliga solressursen i de största bidragande kustområderna, av vilka många ligger i närheten av ekvatorn, undersöks möjligheten att applicera solvärme för smältning av plastavfall. Smältpunkterna av vanlig plast är vanligtvis under 200 °C och ligger således inom området för lågtemperaturparabola solvärmesystem.En prototyp med icke-evakuerat rörparaboliskt tråg konstruerades enligt metoder och tillgänglig teknik för utvecklingsvärlden. Test i Stockholm visade på förmåga att delvis smälta rest ABS från en 3D-skrivare. Interna temperaturer upp till 211 °C registrerades i ytterligare tester i Ioannina, Grekland, där HDPE, LDPE och PP framgångsrikt smältes tillsammans med avfallshushållsartiklar. Värmeförlusten beräknades liksom tillhörande inre dynamik, genom att undersöka samspelet mellan omgivningsförhållandena och de utvalda designparametrarna. Ytterligare testning behövs för att begränsa ytvärmeförlusten vid högre temperaturapplikationer, såsom PET plast som smälter över det uppvisade intervallet. Framtida förädlingar till designen diskuteras liksom den roll som lokala mindre projekt har i minskningen av plastavfall vid dess källa inom utvecklingsländerna

Applications of Solar Thermal Technology for Plastic Waste Management in Developing Communities

As the plastic industry continues to grow globally, with plastic materials contained in a vast quantity of consumer products, the management of the resultant waste has become one of the greatest challenges of our time. Greater than 8 million metric tons of plastics were estimated to enter the world’s oceans as of 2010, with an even larger amount remaining on land. The associated ecological and health effects of plastic waste disposal are many, and existing solutions can only tackle small portions of the waste.China and Indonesia top the current list of contributors to ocean contamination with plastic waste, which is dominated by Asian countries. China in particular is positioned as the world’s leader in plastic production. The waste management scenarios of these countries and associated energy outlooks are discussed, where the plastic waste of the islands of Indonesia is mostly a result of residential, not industrial activities. These calculations are projected to 2025 with recent values of population growth, as an update to previous literature, with Vietnam now expected to supersede both Indonesia and the Philippines. Given the available solar resource in the top coastal plastic waste producing nations, many of which lie within close proximity to the equator, the feasibility of applying solar thermal power for the melting of plastic waste is examined. Melting points of common plastics are typically below 200°C, and thus lie within the range of low-temperature parabolic solar thermal systems.A prototype non-evacuated tube parabolic trough was constructed following methodologies for accessible technologies for the developing world. Tests in Stockholm, Sweden demonstrated its ability to partially melt waste ABS from a 3D printer. Internal temperatures up to 211°C were recorded in further tests in Ioannina, Greece, where HDPE, LDPE, and PP were successfully melted along with waste household items. Heat loss was calculated as well as associated internal dynamics, examining the interaction of ambient conditions with the chosen design parameters. Additional testing is needed to constrain surface heat loss for higher temperature applications such as plastics like PET that melt above the exhibited range. Future refinements to the design are discussed as well as the role micro-projects have in the reduction of plastic waste at its source within developing countries.Plastindustrin fortsätter att växa årligen, med plast som finns i en stor mängd konsumentprodukter, har hanteringen av det resulterande avfallet blivit en av de största utmaningarna i vår tid. Mer än 8 miljoner ton av plast beräknades nå världens hav varje år enligt en studie ifrån 2010, med en ännu större mängd kvar på land. De därmed sammanhängande ekologiska och hälsopåverkande effekterna av att leva med en sådan mängd plastavfall är många, och befintliga lösningar kan bara hantera små delar av avfallet.Kina och Indonesien leder nuvarande lista över bidragsgivare till havsplast, som domineras av asiatiska länder. Kina är i synnerhet världsledande inom plastproduktion. Avfallshanteringsscenarierna i dessa länder och därtill hörande energiutsikter diskuteras, där plastavfallet på Indonesiens öar främst är ett resultat av bostads-, och inte industriell verksamhet. Dessa beräkningar projiceras till 2025 med de senaste värdena av befolkningstillväxt, som en uppdatering till tidigare litteratur, där Vietnam nu förväntas överträffa både Indonesien och Filippinerna. Med tanke på den tillgängliga solressursen i de största bidragande kustområderna, av vilka många ligger i närheten av ekvatorn, undersöks möjligheten att applicera solvärme för smältning av plastavfall. Smältpunkterna av vanlig plast är vanligtvis under 200 °C och ligger således inom området för lågtemperaturparabola solvärmesystem.En prototyp med icke-evakuerat rörparaboliskt tråg konstruerades enligt metoder och tillgänglig teknik för utvecklingsvärlden. Test i Stockholm visade på förmåga att delvis smälta rest ABS från en 3D-skrivare. Interna temperaturer upp till 211 °C registrerades i ytterligare tester i Ioannina, Grekland, där HDPE, LDPE och PP framgångsrikt smältes tillsammans med avfallshushållsartiklar. Värmeförlusten beräknades liksom tillhörande inre dynamik, genom att undersöka samspelet mellan omgivningsförhållandena och de utvalda designparametrarna. Ytterligare testning behövs för att begränsa ytvärmeförlusten vid högre temperaturapplikationer, såsom PET plast som smälter över det uppvisade intervallet. Framtida förädlingar till designen diskuteras liksom den roll som lokala mindre projekt har i minskningen av plastavfall vid dess källa inom utvecklingsländerna

Multi-objective design optimization using dual-level response surface methodology and booth's algorithm for permanent magnet synchronous generators

This paper studies a dual-level response surface methodology (DRSM) coupled with Booth's algorithm using a simulated annealing (BA-SA) method as a multi-objective technique for parametric modeling and machine design optimization for the first time. The aim of the research is for power maximization and cost of manufacture minimization resulting in a highly optimized wind generator to improve small power generation performance. The DRSM is employed to determine the best set of design parameters for power maximization in a surface-mounted permanent magnet synchronous generator (SPMSG) with an exterior-rotor topology. Additionally, the BA-SA method is investigated to minimize material cost while keeping the volume constant. DRSM by different design functions including mixed resolution robust design (MR-RD), full factorial design (FFD), central composite design (CCD), and box-behnken design (BBD) are applied to optimize the power performance resulting in very small errors. An analysis of the variance via multi-level RSM plots is used to check the adequacy of fit in the design region and determines the parameter settings to manufacture a high-quality wind generator. The analytical and numerical calculations have been experimentally verified and have successfully validated the theoretical and multi-objective optimization design methods presented.Peer ReviewedPostprint (published version

Multi-objective design optimization using dual-level response surface methodology and booth's algorithm for permanent magnet synchronous generators

This paper studies a dual-level response surface methodology (DRSM) coupled with Booth's algorithm using a simulated annealing (BA-SA) method as a multi-objective technique for parametric modeling and machine design optimization for the first time. The aim of the research is for power maximization and cost of manufacture minimization resulting in a highly optimized wind generator to improve small power generation performance. The DRSM is employed to determine the best set of design parameters for power maximization in a surface-mounted permanent magnet synchronous generator (SPMSG) with an exterior-rotor topology. Additionally, the BA-SA method is investigated to minimize material cost while keeping the volume constant. DRSM by different design functions including mixed resolution robust design (MR-RD), full factorial design (FFD), central composite design (CCD), and box-behnken design (BBD) are applied to optimize the power performance resulting in very small errors. An analysis of the variance via multi-level RSM plots is used to check the adequacy of fit in the design region and determines the parameter settings to manufacture a high-quality wind generator. The analytical and numerical calculations have been experimentally verified and have successfully validated the theoretical and multi-objective optimization design methods presented.Peer Reviewe

Multiobjective design optimization using dual-level response surface methodology and booth's algorithm for permanent magnet synchronous generators

Peer Reviewe

Benthic grazing in a eutrophic river: cascading effects of zoobenthivorous fish mask direct effects of herbivorous fish

Benthic grazing strongly controls periphyton biomass. The question therefore arises whether benthic grazing could be used as a tool to reduce excessive growth of periphyton in nutrient-enriched rivers. Although benthic invertebrate grazers reduce the growth of periphyton, this is highly context dependent. Here we assessed whether the only obligate herbivorous fish in European rivers, the common nase (Chondrostoma nasus L.), is able to reduce periphyton biomass in a eutrophic river. We conducted three consecutive in situ experiments at low, intermediate and high densities of nase in the river using standard tiles on the river bottom naturally covered with periphyton that were accessible to fish and tiles that excluded fish foraging with electric exclosures. The biomass of benthic invertebrate grazers was very low relative to nase. We hypothesised that nase would reduce periphyton biomass on accessible tiles and therefore expected higher periphyton biomass on the exclosure tiles, at least at intermediate and high densities of nase in the river. Contrary to our expectation, the impact of fish grazing was low even at high fish density, as judged by the significantly lower chlorophyll a concentration on exclosure tiles even though the ash-free dry mass on accessible and exclosure tiles did not differ. The lower chlorophyll a concentrations on exclosure tiles might be explained by a higher biomass of invertebrate grazers on the exclosure tiles, which would indicate that the effect of invertebrate grazers was stronger than that of herbivorous fish grazers. The high biomass of invertebrate grazers on exclosure tiles likely arose from the exclusion of zoobenthivorous fish, which occur in the river at high densities. The results of our small-scale experiments suggested that cascading top-down effects of zoobenthivorous fish have a higher impact on periphyton biomass than direct effects of herbivorous nase