The Experts below are selected from a list of 225 Experts worldwide ranked by ideXlab platform
Alex A Elvin - One of the best experts on this subject based on the ideXlab platform.
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Feasibility of structural monitoring with vibration Powered sensors
Smart Materials and Structures, 2006Co-Authors: Niell G Elvin, Nizar Lajnef, Alex A ElvinAbstract:Wireless sensors and sensor networks are beginning to be used to monitor structures. In general, the longevity, and hence the efficacy, of these sensors are severely limited by their stored Power. The ability to convert abundant ambient energy into electric Power would eliminate the problem of drained Electrical supply, and would allow indefinite monitoring. This paper focuses on vibration in civil engineering structures as a source of ambient energy; the key question is can sufficient energy be produced from vibrations? Earthquake, wind and traffic loads are used as realistic sources of vibration. The theoretical maximum energy levels that can be extracted from these dynamic loads are computed. The same dynamic loads are applied to a piezoelectric generator; the energy is measured experimentally and computed using a mathematical model. The collected energy levels are compared to the energy requirements of various electronic subsystems in a wireless sensor. For a 5 cm3 sensor node (the volume of a typical concrete stone), it is found that only extreme events such as earthquakes can provide sufficient energy to Power wireless sensors consisting of modern electronic chips. The results show that the optimal Generated Electrical Power increases approximately linearly with increasing sensor mass. With current technology, it would be possible to self-Power a sensor node with a mass between 100 and 1000 g for a bridge under traffic load. Lowering the energy consumption of electronic components is an ongoing research effort. It is likely that, as electronics becomes more efficient in the future, it will be possible to Power a wireless sensor node by harvesting vibrations from a volume generator smaller than 5 cm^3
Niell G Elvin - One of the best experts on this subject based on the ideXlab platform.
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Feasibility of structural monitoring with vibration Powered sensors
Smart Materials and Structures, 2006Co-Authors: Niell G Elvin, Nizar Lajnef, Alex A ElvinAbstract:Wireless sensors and sensor networks are beginning to be used to monitor structures. In general, the longevity, and hence the efficacy, of these sensors are severely limited by their stored Power. The ability to convert abundant ambient energy into electric Power would eliminate the problem of drained Electrical supply, and would allow indefinite monitoring. This paper focuses on vibration in civil engineering structures as a source of ambient energy; the key question is can sufficient energy be produced from vibrations? Earthquake, wind and traffic loads are used as realistic sources of vibration. The theoretical maximum energy levels that can be extracted from these dynamic loads are computed. The same dynamic loads are applied to a piezoelectric generator; the energy is measured experimentally and computed using a mathematical model. The collected energy levels are compared to the energy requirements of various electronic subsystems in a wireless sensor. For a 5 cm3 sensor node (the volume of a typical concrete stone), it is found that only extreme events such as earthquakes can provide sufficient energy to Power wireless sensors consisting of modern electronic chips. The results show that the optimal Generated Electrical Power increases approximately linearly with increasing sensor mass. With current technology, it would be possible to self-Power a sensor node with a mass between 100 and 1000 g for a bridge under traffic load. Lowering the energy consumption of electronic components is an ongoing research effort. It is likely that, as electronics becomes more efficient in the future, it will be possible to Power a wireless sensor node by harvesting vibrations from a volume generator smaller than 5 cm^3
Shashank Priya - One of the best experts on this subject based on the ideXlab platform.
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High Power Magnetic Field Energy Harvesting through Amplified Magneto-Mechanical Vibration
Advanced Energy Materials, 2018Co-Authors: Min Gyu Kang, Geon Tae Hwang, Jinsung Chun, Rammohan Sriramdas, Hyeon Lee, Deepam Maurya, Jungho Ryu, Shashank PriyaAbstract:© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Internet of Things (IoT) is driving the development of new generation of sensors, communication components, and Power sources. Ideally, IoT sensors and communication components are expected to be Powered by sustainable energy source freely available in the environment. Here, a breakthrough in this direction is provided by demonstrating high output Power energy harvesting from very low amplitude stray magnetic fields, which exist everywhere, through magnetoelectric (ME) coupled magneto-mechano-electric (MME) energy conversion. ME coupled MME harvester comprised of multiple layers of amorphous magnetostrictive material, piezoelectric macrofiber composite, and magnetic tip mass, interacts with an external magnetic field to generate Electrical energy. Comprehensive experimental investigation and a theoretical model reveal that both the magnetic torque Generated through magnetic loading and amplification of magneto-mechanical vibration by ME coupling contributes toward the generation of high Electrical Power from the stray magnetic field around Power cables of common home appliances. The Generated Electrical Power from the harvester is sufficient for operating microsensors (gyro, temperature, and humidity sensing) and wireless data transmission systems. These results will facilitate the deployment of IoT devices in emerging intelligent infrastructures.
Philippe Poure - One of the best experts on this subject based on the ideXlab platform.
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Fully Electrical Modeling of Thermoelectric Generators with Contact Thermal Resistance Under Different Operating Conditions
Journal of Electronic Materials, 2017Co-Authors: Saima Siouane, Slaviša Jovanović, Philippe PoureAbstract:The Seebeck effect is used in thermoelectric generators (TEGs) to supply electronic circuits by converting the waste thermal into Electrical energy. This Generated Electrical Power is directly proportional to the temperature difference between the TEG module’s hot and cold sides. Depending on the applications, TEGs can be used either under constant temperature gradient between heat reservoirs or constant heat flow conditions. Moreover, the Generated Electrical Power of a TEG depends not only on these operating conditions, but also on the contact thermal resistance. The influence of the contact thermal resistance on the Generated Electrical Power have already been extensively reported in the literature. However, as reported in Park et al. (Energy Convers Manag 86:233, 2014) and Montecucco and Knox (IEEE Trans Power Electron 30:828, 2015), while designing TEG-Powered circuit and systems, a TEG module is mostly modeled with a Thévenin equivalent circuit whose resistance is constant and voltage proportional to the temperature gradient applied to the TEG’s terminals. This widely used simplified Electrical TEG model is inaccurate and not suitable under constant heat flow conditions or when the contact thermal resistance is considered. Moreover, it does not provide realistic behaviour corresponding to the physical phenomena taking place in a TEG. Therefore, from the circuit designer’s point of view, faithful and fully Electrical TEG models under different operating conditions are needed. Such models are mainly necessary to design and evaluate the Power conditioning electronic stages and the maximum Power point tracking algorithms of a TEG Power supply. In this study, these fully Electrical models with the contact thermal resistance taken into account are presented and the analytical expressions of the Thévenin equivalent circuit parameters are provided.
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Fully Electrical Modeling of Thermoelectric Generators with Contact Thermal Resistance Under Different Operating Conditions
Journal of Electronic Materials, 2016Co-Authors: Saima Siouane, Slavisa Jovanovic, Philippe PoureAbstract:The Seebeck effect is used in thermoelectric generators (TEGs) to supply electronic circuits by converting the waste thermal into Electrical energy. This Generated Electrical Power is directly proportional to the temperature difference between the TEG module’s hot and cold sides. Depending on the applications, TEGs can be used either under constant temperature gradient between heat reservoirs or constant heat flow conditions. Moreover, the Generated Electrical Power of a TEG depends not only on these operating conditions, but also on the contact thermal resistance. The influence of the contact thermal resistance on the Generated Electrical Power have already been extensively reported in the literature. However, as reported in Park et al. (Energy Convers Manag 86:233, 2014) and Montecucco and Knox (IEEE Trans Power Electron 30:828, 2015), while designing TEG-Powered circuit and systems, a TEG module is mostly modeled with a Thevenin equivalent circuit whose resistance is constant and voltage proportional to the temperature gradient applied to the TEG’s terminals. This widely used simplified Electrical TEG model is inaccurate and not suitable under constant heat flow conditions or when the contact thermal resistance is considered. Moreover, it does not provide realistic behaviour corresponding to the physical phenomena taking place in a TEG. Therefore, from the circuit designer’s point of view, faithful and fully Electrical TEG models under different operating conditions are needed. Such models are mainly necessary to design and evaluate the Power conditioning electronic stages and the maximum Power point tracking algorithms of a TEG Power supply. In this study, these fully Electrical models with the contact thermal resistance taken into account are presented and the analytical expressions of the Thevenin equivalent circuit parameters are provided.
Derrick Holliday - One of the best experts on this subject based on the ideXlab platform.
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Thermography-Based Virtual MPPT Scheme for Improving PV Energy Efficiency Under Partial Shading Conditions
IEEE Transactions on Power Electronics, 2014Co-Authors: Yihua Hu, Jiande Wu, Bing Ji, Derrick HollidayAbstract:This paper proposes a new thermography-based maximum Power point tracking (MPPT) scheme to address photovoltaic (PV) partial shading faults. Solar Power generation utilizes a large number of PV cells connected in series and in parallel in an array, and that are physically distributed across a large field. When a PV module is faulted or partial shading occurs, the PV system sees a nonuniform distribution of Generated Electrical Power and thermal profile, and the generation of multiple maximum Power points (MPPs). If left untreated, this reduces the overall Power generation and severe faults may propagate, resulting in damage to the system. In this paper, a thermal camera is employed for fault detection and a new MPPT scheme is developed to alter the operating point to match an optimized MPP. Extensive data mining is conducted on the images from the thermal camera in order to locate global MPPs. Based on this, a virtual MPPT is set out to find the global MPP. This can reduce MPPT time and be used to calculate the MPP reference voltage. Finally, the proposed methodology is experimentally implemented and validated by tests on a 600-W PV array.