Design of an Inductorless Power Converter with Maximizing Power Extraction for Energy Harvesting

2018 ◽  
pp. 63-75
Author(s):  
Ridvan Umaz ◽  
Lei Wang
Keyword(s):  
Energy Harvesting ◽  
Power Converter ◽  
Power Extraction

Design of an Inductorless Power Converter with Maximizing Power Extraction for Energy Harvesting

2018 ◽  
Vol 27 (01n02) ◽  
pp. 1840007 ◽  
Author(s):  
Ridvan Umaz ◽  
Lei Wang
Keyword(s):  
Energy Source ◽  
Energy Harvesting ◽  
Low Power ◽  
Power Converter ◽  
Energy Sources ◽  
Cmos Process ◽  
Output Current ◽  
Power Extraction ◽  
Two Stages ◽  
Extracted Power

An inductorless power converter for low-power energy harvesting is presented. The power converter for energy harvesting is employed to maximize power extraction from energy sources. The power converter is based on a capacitive boost converter which is divided into two stages; a number of first-stage in parallel and shared-stage. The first-stage maximizes power extraction from the energy source while the shared-stage operates as a conventional charge pump. For not only low-power energy source but also high-power energy source, the maximum power extraction is targeted by the proposed converter. The extracted power from energy sources enhances by range from 117% to 161% over the conventional design. The output current of the proposed converter with three first-stages is improved by 183% over conventional converter. The peak efficiencies achieved with three and one first-stage are 53.3% and 38.5% for the proposed and the conventional converters, respectively. The peak end-to-end efficiency is enhanced by 198% as compared to the conventional converter. The proposed inductorless power converter has been implemented on a 0.13μm CMOS process.

scholarly journals Enhanced Power Extraction with Sediment Microbial Fuel Cells by Anode Alternation

Fuels ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 168-178
Author(s):  
Marzia Quaglio ◽  
Daniyal Ahmed ◽  
Giulia Massaglia ◽  
Adriano Sacco ◽  
Valentina Margaria ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Energy Harvesting ◽  
Power Density ◽  
Microbial Fuel Cells ◽  
Average Power ◽  
Power Extraction ◽  
Harvesting Technique ◽  
Harvesting Method ◽  
Energy Harvesting Devices ◽  
Efficient Power

Sediment microbial fuel cells (SMFCs) are energy harvesting devices where the anode is buried inside marine sediment, while the cathode stays in an aerobic environment on the surface of the water. To apply this SCMFC as a power source, it is crucial to have an efficient power management system, leading to development of an effective energy harvesting technique suitable for such biological devices. In this work, we demonstrate an effective method to improve power extraction with SMFCs based on anodes alternation. We have altered the setup of a traditional SMFC to include two anodes working with the same cathode. This setup is compared with a traditional setup (control) and a setup that undergoes intermittent energy harvesting, establishing the improvement of energy collection using the anodes alternation technique. Control SMFC produced an average power density of 6.3 mW/m2 and SMFC operating intermittently produced 8.1 mW/m2. On the other hand, SMFC operating using the anodes alternation technique produced an average power density of 23.5 mW/m2. These results indicate the utility of the proposed anodes alternation method over both the control and intermittent energy harvesting techniques. The Anode Alternation can also be viewed as an advancement of the intermittent energy harvesting method.

scholarly journals Numerical Study of an Oscillating-Wing Wingmill for Ocean Current Energy Harvesting: Fluid-Solid-Body Interaction with Feedback Control

2020 ◽  
Vol 9 (1) ◽  
pp. 23
Author(s):  
David Balam-Tamayo ◽  
Carlos Málaga ◽  
Bernardo Figueroa-Espinoza
Keyword(s):  
Energy Harvesting ◽  
Numerical Study ◽  
Angle Of Attack ◽  
Ocean Current ◽  
Control Synthesis ◽  
Dimensionless Number ◽  
Control Law ◽  
Loop Control ◽  
Power Extraction ◽  
Current Energy

The performance and flow around an oscillating foil device for current energy extraction (a wingmill) was studied through numerical simulations. OpenFOAM was used in order to study the two-dimensional (2D) flow around a wingmill. A closed loop control law was coded in order to follow a reference angle of attack. The objective of this control law is to modify the angle of attack in order to enhance the lift force (and increase power extraction). Dimensional analysis suggests a compromise between the generator (or damper) stiffness and actuator/control gains, so a parametric study was carried out while using a new dimensionless number, called B, which represents this compromise. It was found that there is a maximum on the efficiency curve in terms of the aforementioned dimensionless parameter. The lessons that are learned from this fluid-structure and feedback coupling are discussed; this interaction, combined with the feedback dynamics, may trigger dynamic stall, thus decreasing the performance. Moreover, if the control strategy is not carefully selected, then the energy spent on the actuator may affect efficiency considerably. This type of simulation could allow for the system identification, control synthesis, and optimization of energy harvesting devices in future studies.

Hydrokinetic Energy Harvesting System From Vortex Induced Vibrations of Submerged Bodies

2011 ◽  
Author(s):  
Varun Lobo ◽  
Arindam Banerjee ◽  
Nyuykighan Mainsah ◽  
Jonathan Kimball
Keyword(s):  
Boundary Layer ◽  
Energy Harvesting ◽  
Vortex Shedding ◽  
Computational Study ◽  
High Energy ◽  
Power Converter ◽  
Design Parameters ◽  
Hydrokinetic Energy ◽  
Energy Harvesting System ◽  
Efficient Power

A Vortex Induced Vibration (VIV) based hydrokinetic energy system is discussed in this paper. Vibrations induced on a body (facing an external flow) due to the periodic irregularities in the flow caused by boundary layer separation are called as VIV. This separation of the boundary layer from the surface causes vortex formation in the wake region of the cylinder. The lift-force or the transverse oscillation of the vibrating cylinder depends upon the strength and modes of the vortex formed. The VIV energy harvesting system is based on the idea of maximizing rather than spoiling vortex shedding and was discovered in 2004 at the University of Michigan by Bernitsas and Raghavan. The vibrating bodies will in turn be used to harness energy using an efficient power-take-off system. In this paper, we discuss the hydrodynamic design of such a VIV based energy harvesting system using computational fluid dynamics. A fluid structure interaction calculation is performed to determine the forces on the surface of a bluff body due to separation of vortices from the surface. The hydrodynamic forces that act on such a system depend on the cylinder diameter, flow velocity, modes of vortex shedding and arrangement of cylinder(s). A detailed computational study on the effect of different design parameters listed above are first carried on a single cylinder arrangement; this is followed by a more detailed analysis that is extended to multiple cylinders. For a two-cylinder arrangement, the positions in which the cylinders are placed are also found to play an important role, as the vortex shed from one cylinder may be used to enhance the forces of lift on another cylinder present in its wake. Furthermore, the design of a VIV generator requires optimal damping and low mass ratio to enable high energy conversion via an efficient power take-off mechanism. The working and design considerations of the energy converter is outlined starting with a set of basic definitions pertaining to this technology. A tubular linear interior permanent magnet generator (TL-IPM) connected to a power converter is used; a linear generator was chosen to minimize mechanical components, such as gears or cams in the system.

An Ultra Low Voltage Resonant Converter for Thermoelectric Energy Harvesting

2013 ◽  
Vol 772 ◽  
pp. 731-734
Author(s):  
Shi Zhong Guo ◽  
Kai Xie ◽  
Ying Hao Ye ◽  
Xiao Ping Li
Keyword(s):  
Energy Harvesting ◽  
Low Voltage ◽  
Power Converter ◽  
Resonant Converter ◽  
Transfer Energy ◽  
Thermoelectric Energy ◽  
Thermoelectric Energy Harvesting ◽  
Energy Transducer ◽  
Energy Harvesting System ◽  
Energy Buffer

This paper presents a ultra low voltage resonant converter for thermoelectric energy harvesting.A key challenge in designing energy harvesting system is that thermoelectric generators output a very low voltage (-0.3V~0.3V). Therefore, a power converter is used to boost the output voltage of the energy transducer and transfer energy into an energy buffer for storage. The converter operates from input voltages ranging from-500mV to-60mV and 60mV to 500mV while supplying a 4.2 V DC output. The converter consumes 88μW of quiescent power, delivers up to 1.6 (1.8) mW of output power, and is 65(67)% efficient for a-100mV and 100mV input, respectively.

scholarly journals Resonant Rectifier ICs for Piezoelectric Energy Harvesting Using Low-voltage Drop Diode Equivalents

2017 ◽  
Author(s):  
Amad Ud Din ◽  
Seneke Chamith Chandrathna ◽  
Jong-Wook Lee
Keyword(s):  
Energy Harvesting ◽  
Integrated Circuits ◽  
Low Voltage ◽  
Voltage Drop ◽  
Power Conversion ◽  
Cmos Process ◽  
Power Extraction ◽  
Piezoelectric Energy ◽  
Bridge Rectifier ◽  
External Power

Herein, we present the design technique of a resonant rectifier for piezoelectric (PE) energy harvesting. We propose two diode equivalents to reduce the voltage drop in the rectifier operation, a minuscule-drop-diode equivalent (MDDE) and a low-drop-diode equivalent (LDDE). The diode equivalents are embedded in resonant rectifier integrated circuits (ICs), which use symmetric bias-flip to reduce the power wasted for charging and discharging the internal capacitance of a PE transducer. The self-startup function is supported by synchronously generating control pulses for the bias-flip from the PE transducer. Two resonant rectifier ICs, using both MDDE and LDDE, are fabricated in a 0.18 μm CMOS process and their performances are characterized under external and self-power conditions. Under the external-power condition, the rectifier using LDDE delivers an output power POUT of 564 μW and a rectifier output voltage VRECT of 3.36 V with a power conversion efficiency (PCE) of 90.1%. Under self-power conditions, the rectifier using MDDE delivers a POUT of 288 μW and a VRECT of 2.4 V with a corresponding PCE of 74.6%. The result shows that the power extraction capability of the proposed rectifier is 5.9 and 3.0 times higher than that of a conventional full-bridge rectifier.

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