Harvesting Circuit Research Articles

Experimental investigation of near-field magnetic energy harvesting from induction cooktop

This paper proposes a simple and cost-effective magnetic-field-energy harvesting circuit for capturing the leaked magnetic energy from an induction cooktop. In this, the captured energy is converted into dc electrical energy with the help of 1N5819 Schottky diodes based full wave bridge rectifier. We investigated the captured magnetic-field energy at different positions and different heights of the energy-harvesting coil from the induction cooktop. The designed Magnetic-Field-Energy Harvesting (MFEH) circuit is capable of capturing an average dc power of 1484 mW while it is placed 5 cm below the induction cooktop with a load resister 33 Ω and capacitance of 470 μF. The power level is reduced to 203 mW when the energy harvesting coil is moved to 10 cm below the induction cooktop. The harvested magnetic field energy at different positions of the energy harvesting coils is investigated for different values of load resisters. The harvested energy can be stored in a battery for future applications. The proposed device demonstrated practically for charging mobile and powering the low-power IoT device. The numerical study of the proposed harvesting mechanism is explained also. The induction cooktop’s yielded excellent results and magnetic field energy harvesting capability make the proposed device unique from the previously reported magnetic harvesting circuits.

Energy-efficient routing, power control and energy clustering for energy harvesting-enabled spectrum sharing IoT sensor networks

We investigate a spectrum sharing system that enables energy harvesting from distributed multi-antenna energy transmitter devices for primary dual-band device-to-device networks and secondary dual-band wireless sensor networks (WSNs), incorporating a multi-stage rectenna energy harvesting circuit model. We formulate a new multi-hop routing problem for network energy efficiency maximization of this system, which involves the interconnected tasks of WSN routing, controlling the transmit power of sensor nodes, and energy transmitter clustering, taking into account interference, power budget and rate constraints. To tackle these interconnected tasks effectively, we propose an integrated solution that includes both centralized and distributed routing schemes. Furthermore, the solution incorporates energy transmitter clustering schemes based on harvested power and channel gain. We provide an analysis of the computation complexity and signaling overhead for the proposed solution. Our simulation results demonstrate that the proposed routing and clustering schemes outperform their respective benchmark schemes, achieving significant performance gains.

Synchronized switch charge constrained conditioning circuit for electrostatic energy harvesting

Electrostatic energy harvesting conditioning circuits usually rely on triangular or rectangular shaped energy cycles. While the former enables significant converted energy, its complexity raises significant issues in realistic applications. Rectangular cycles can be implemented using purely passive components but feature limited conversion abilities. This study bridges the gap between these two approaches, presenting a semi-passive technique consisting of charging and discharging the transducer synchronously with the structure motion, using controlled switches that can be easily implemented while ensuring triangular cycles. Theoretical analysis and experimental validation of such an electrostatic energy harvesting circuit with synchronized controlled switches confirm that this technique provides a simple configuration while ensuring the efficiency of the triangular cycle. To validate the proposed circuit design, a system was employed featuring a rotating metallic variable capacitor designed to mechanically open two magnetic reed switches. This system seamlessly integrates with the devised circuit. The total energy converted by the entire system is estimated to be approximately 1 μJ per cycle, considering a storage component comprising a precharged 1 μF capacitor at 60 V. Yet, results demonstrated that efficiently transferring this energy to the storage stage requires transducers with low losses. While in the presented experimental test an off-the-shelf generic transducer showed high losses, resulting in only 24 nJ per cycle to be harvested, it is believed that specific high quality electrostatic device can benefit from this approach for efficient energy harvesting systems.

An RF Power Amplifier Integrated With the Self-Health Monitor Sensor and Multisource Energy Harvesting Circuit

An RF Power Amplifier Integrated With the Self-Health Monitor Sensor and Multisource Energy Harvesting Circuit

Energy Harvesting in Electric Power Systems for Data Communication Purposes

Aiming to illuminate the path towards integrating energy harvesting (EH) technologies into modern electric power systems, thereby enabling more efficient and sustainable energy solutions, this paper explores energy harvesting within electric power systems and points out its potential to power data communication purposes. In this sense, we examine the overarching principles of EH in these systems, spotlighting both the merits and limitations associated with energy extraction across varying voltage levels and electric signal frequency bands. Central components of EH devices, alongside a spectrum of harvesting methodologies, are thoroughly reviewed. Also, we showcase a case study that provides a quantitative assessment of EH potential in electric power systems. The manuscript culminates in a forward-looking analysis of EH, considering emerging technologies that promise to redefine the landscape. These include integrating hybrid power line and wireless systems, strategies for optimal power allocation, enhancements in physical layer security, the innovative concept of negawatts, advancements in harvesting circuit designs and applying non-orthogonal multiple access techniques

A multisource energy harvesting circuit for vibration and light energy with MPPT

SummaryThe article presents a multisource energy harvesting circuit (MEHC) for vibration and light energy with maximum power point tracking (MPPT). The MEHC has a cold start capability and extracts energy from piezoelectric transducers (PZTs) and photovoltaic cells (PVs) simultaneously when the multi PZTs reach their peak open‐circuit (OC) voltage, detected by the peak voltage detector and the PV1 cell voltage exceeds the MPP voltage (MPP voltage is approximately 0.7 times the PV cell's OC voltage) during the off‐peak time of the PZTs. The experimental results indicate that the output power of the MEHC is 2.8 mW under certain conditions, and the maximum energy extraction efficiency of the PVs is about 75%. The output power of the MEHC is 4.59 times of that without PVs.

Omnidirectional Flexible Tri-Band Rectenna With Eliminated Matching Circuit for Ambient RF Energy Harvesting

Omnidirectional Flexible Tri-Band Rectenna With Eliminated Matching Circuit for Ambient RF Energy Harvesting

An Efficient Electrothermal Model of a Thermoelectric Converter for a Thermal Energy Harvesting Process Simulation and Electronic Circuits Powering

This paper deals with an electrothermal model of a thermoelectric converter dedicated to performing simulations of coupled thermal and electrical phenomena taking place in harvesting processes. The proposed model is used to estimate the electrical energy gain from waste heat that would be sufficient to supply electronic circuits, in particular autonomous battery-less nodes of wireless sensor networks (WSN) and Internet of Things (IoT) devices. The developed model is not limited to low-power electronic solutions such as WSN or IoT; it can also be scaled up and applied to simulations of considerably higher thermal power conversion. In this paper, a few practical case studies are presented that show the feasibility and suitability of the proposed model for complex simultaneous simulation processes in both the electrical and thermal domains. The first example deals with a combined simulation of the electrothermal model of a thermoelectric generator (TEG) and an electronic harvester circuit based on Analog Devices’ power management integrated circuit LTC3108. The second example relates to the thermalization effect in heat sink-less harvesting applications that could be mitigated by a pulse mode operation. The unique contribution and advancement of the model is the hierarchical structure for scaling up and down, incorporating the complexity of the Seebeck effect, the Joule effect, heat conduction, as well as the temperature dependence of the used materials and the thermoelectric pellet geometries. The simulations can be performed in steady as well as transient states under changing electrical loads and temperatures.

Outage and throughput performance analysis of smart UAV‐assisted full‐duplex NOMA‐based energy harvesting cognitive radio networks

SummaryIn this paper, the throughput and outage performance for an unmanned aerial vehicle (UAV)‐assisted non‐orthogonal multiple access (NOMA)‐based hybrid cognitive radio (CR) network are examined under m‐Nakagami fading channel. To be more specific, a secondary source transmitter ( ) broadcasts a NOMA‐enabled mixed signal to secondary destinations via UAV relay, which operates in full‐duplex (FD) mode and employs decode‐and‐forward protocol. In our approach, an energy harvesting (EH) circuit is employed at both and UAV to harvest energy from the PU radio frequency (RF) signals. These secondary transmitters are also incorporated with energy detector (ED) circuit as well, which detects the activity of the primary user (PU). The status of PU to be busy or idle is confirmed on the basis of the energy detector's results. In turn, this drives and UAV to switch between underlay and overlay protocols in an adaptive manner to increase spectrum efficiency (SE). The closed form mathematical expressions of the secondary outage probability for NOMA‐based UAV equipped CR networks under imperfect successive interference cancellation (i‐SIC) conditions have been evaluated. The administration of the power allocation policy at the and UAV is assessed while maintaining the PU quality of service (QoS). Finally, MATLAB simulation testbed has been used to verify all the analytical closed form expressions.

Enhanced thermal and angular velocity-induced hybrid piezoelectric energy harvesting of smart turbine blades

In this study, an approach is proposed to examine hybrid piezoelectric energy harvesting performances from vibrations induced by thermal and angular velocity loads in order to generate energy from the smart turbine blade. In the proposed method, a smart turbine blade is formed by patching the piezoelectric material to the root surface of the turbine blade. A finite element (FE) model of the smart turbine blade is established and then it is validated with a smart blade model in a reference study to test the reliability and accuracy of the FE method. The defined loads are applied to the smart blade to obtain energy from mechanical vibrations induced by thermal and angular velocity loads. Temperature distribution, voltage, and vibration results obtained from energy harvesting analysis under different thermal and angular velocity loads are presented. In order to investigate the energy conversion efficiency of the energy obtained from the system, the energy harvesting circuit is tested in terms of battery discharge times and power output values. The results show that while the maximum energy conversion in the thermally induced smart turbine blade is 11.9 W, a power output of 12.3 W is obtained from the hybrid energy harvesting mechanism under angular velocity and heat flux loads.

Isotropic ΙoT-Based Magnetic Flux Density Meter Implementation for ELF Field Measurements

This article presents the basic principles for an Extremely Low Frequency (ELF) IoT-based isotropic meter implementation, which can measure magnetic flux density from 100 nT up to 10 μT. The identical sensor probes are used for isotropic field measurements in the X, Y, and Z planes. The prototype has a flat response across the frequency range from 40 Hz to 10 kHz, detecting and measuring several magnetic field sources. The proposed low-cost meter can measure fields from the power supply network and its harmonic frequencies in the operating frequency band. The proposed magnetic flux density meter circuit is simple to implement and the measured field can be displayed on any mobile device with Wi-Fi connectivity. An Arduino board with the embedded Wi-Fi Nina module is responsible for data transferring from the sensor to the cloud as a complete IoT solution, supported by the Blynk application via Android and iOS operating systems or web interface. In addition, an ELF energy harvesting (EH) circuit was also proposed in our study for the utilization of the alternating magnetic fields (50 Hz) derived from the operation of several consumer devices such as transformers, power supplies, hair dryers, etc. using low-consumption applications. Experimental measurements showed that the (DC) harvesting voltage can reach up to 4.2 volts from the magnetic field of 33 μΤ, caused by the operation of an electric hair dryer and can fully charge the 100 μF storage capacitor (Cs) of the proposed EH system in about 3 min.

A comparative analysis of parallel SSHI and SEH for bistable vibration energy harvesters

The present work focuses on ambient vibration energy harvesting. Specifically, this article deals with bistable piezoelectric energy harvesters (PEHs) which exhibits a wider bandwidth than linear oscillators. These complex systems require an energy extraction circuit (EEC) to rectify their voltage to supply power to autonomous sensors. This EEC needs to be optimized in order to increase the harvested power and even the bandwidth of PEHs. Because of the complex dynamics of bistable PEHs, there is a lack of simple and physically-insightful models in the literature that would allow the understanding and optimization of the extraction circuit. To address this issue, the present work derives closed-form models of a bistable PEH coupled to a passive and an active synchronous EEC: respectively the standard energy harvesting (SEH) circuit and the parallel synchronized switch harvesting on inductor (P-SSHI) circuit. Experimental measurements conducted on a custom bistable PEH demonstrate the validity of the proposed models with a relative error lower than 15% on the harvested power and the bandwidth. The proposed models allow to easily understand the influence of the P-SSHI circuit on the dynamics of a bistable PEH. Moreover, a comparison of the performance of the SEH and the P-SSHI circuits, valid for any bistable generator, is proposed. The latter shows that under low electromechanical coupling and low acceleration amplitude the P-SSHI circuit leads to multiply the maximum harvested power up to 4.3 compared to the SEH circuit, and the bandwidth by a factor of 2.3.

Study and implementation of a novel high‐efficiency piezoelectric energy harvesting circuit

SummaryThis paper proposes a self‐powered SSHI piezoelectric energy extraction circuit combined with Modified FOCV‐MPPT technology, which analyzes the electrical characteristics of S‐SSHI operation. The paper demonstrates that the determination of the optimal operating state of S‐SSHI can be determined independently of the open‐circuit voltage. Based on the key parameters obtained from the theoretical analysis, the FOCV‐MPPT strategy is modified, and the corresponding functional circuit is designed. This strategy serves as an intermediate stage between S‐SSHI and the load, addressing the dependence of S‐SSHI output power on the load while avoiding the power supply interruption issue of the traditional FOCV‐MPPT strategy. In addition, the higher output power provided by S‐SSHI improves the utilization of MPPT technology. The correctness of the investigations is verified through the simulation and experiments. By using self‐powered S‐SSHI, the proposed circuit increases the output power of PEH by a factor of 2.46. In the open‐circuit voltage range of 2–7 V, the average maximum power tracking efficiency achieved 90.1%. The maximum tracking efficiency can reach 98%.

Research on the Optimization of Synchronous Switch Energy Harvesting Circuit Based on Capacitor

As advanced systems continue to advance and fuse functions expand, the demand for higher power supply requirements for fuses has increased. Consequently, researchers have turned their attention to the recovery of energy from the environment. Piezoelectric energy harvesting has gained significant popularity due to its advantageous characteristics, such as high energy density, ease of implementation, and compact size. However, the presence of various component types within the energy harvesting circuit inevitably results in the generation of reactive power, leading to a reduction in the circuit’s power factor. To address this issue, this paper introduces the adoption of the third-order valley-fill circuit as the power factor correction circuit. The implementation process involves the utilization of Multisim software to simulate the double-limit zero-crossing detection circuit, pulse signal generation circuit, and power factor correction circuit. Furthermore, the aforementioned circuits were subjected to plate-level welding, followed by individual tests to evaluate the effectiveness of the double-limit zero-crossing detection, pulse signal test, and load voltage measurement. These findings unequivocally exemplify the successful accomplishment of the intended objective of augmenting the output power by the third-order valley-fill circuit.

Interaction Harvesting

Whenever a user interacts with a device, mechanical work is performed to actuate the user interface elements; the resulting energy is typically wasted, dissipated as sound and heat. Previous work has shown that many devices can be powered entirely from this otherwise wasted user interface energy. For these devices, wires and batteries, along with the related hassles of replacement and charging, become unnecessary and onerous. So far, these works have been restricted to proof-of-concept demonstrations; a specific bespoke harvesting and sensing circuit is constructed for the application at hand. The challenge of harvesting energy while simultaneously sensing fine-grained input signals from diverse modalities makes prototyping new devices difficult. To fill this gap, we present a hardware toolkit which provides a common electrical interface for harvesting energy from user interface elements. This facilitates exploring the composability, utility, and breadth of enabled applications of interaction-powered smart devices. We design a set of "energy as input" harvesting circuits, a standard connective interface with 3D printed enclosures, and software libraries to enable the exploration of devices where the user action generates the energy needed to perform the device's primary function. This exploration culminated in a demonstration campaign where we prototype several exemplar popular toys and gadgets, including battery-free Bop-It--- a popular 90s rhythm game, an electronic Etch-a-sketch, a "Simon-Says"-style memory game, and a service rating device. We run exploratory user studies to understand how generativity, creativity, and composability are hampered or facilitated by these devices. These demonstrations, user study takeaways, and the toolkit itself provide a foundation for building interactive and user-focused gadgets whose usability is not affected by battery charge and whose service lifetime is not limited by battery wear.

Stand-alone floating microbial fuel cell-based biosensor for tracking organic pollution influx

Organic wastewater discharge is an alarming issue with freshwater lakes and rivers. This research developed a self-powered stand-alone floating biosensor based on a microbial fuel cell (MFC) for early organic wastewater detection. The MFC case was fabricated by a 3D printer, and the electrodes were fabricated from low-cost carbon-based materials. Soil containing electrogenic bacteria was loaded on the anode to increase the sensitivity and stability of the biosensor. In this research, chemical oxygen demand (COD) was used to represent the organic content of water. Experimental data showed a linear relationship between the COD of water and the output voltage of the MFC. Moreover, an energy harvesting circuit equipped with a flashing light-emitting diode (LED) was powered by the MFC. The LED started to flash when the COD of water was about 60 mg/L, and the flashing pace increased as the COD increased. As a result, organic content in water could be detected by the device and visually represented through the flashing pace of the LED. This solution potentially enables a simple and low-cost measure for water quality control at the input of freshwater lakes and rivers.

An Environmental Energy Harvesting-Driven Wireless Parking Detection Method: Analysis and Implementation

The Smart Parking System (SPS) has played an important role in solving the parking problem in urban areas recently, resulting in that the battery-powered Wireless Parking Detectors (WPDs) based on Internet of Things (IoT) technology have been widely used in SPS to collect basic data sets. However, the daily turnover rates of parking spaces are generally less than 10 vehicles in Shanghai, China, so that WPDs waste a lot of energy in collecting and processing of redundant sensor data when the parking space is occupied or free. Hence, an environmental Energy Harvesting-driven Parking Detection (EHPD) method, which includes a vehicle-induced vibration energy harvesting and conditioning circuit, as well as a parking detection algorithm based on the signatures of vehicle-induced seismic signals and wireless energy attenuated by vehicles, is proposed in the paper. In EHPD, the signatures of pulse signals converted from vehicle-induced seismic signals are used to drive the wireless energy features to participate in achieving parking detection. Finally, the proposed EHPD has been evaluated in a real testbed, and the experimental results show that it can achieve the same functions as the existing magnetometer-based WPD devices with lower cost and energy consumption.

(Invited) Harvesting Energy from Freestanding Graphene Thermal Fluctuations

Highly flexible, electrically conductive freestanding graphene membranes hold great promise for vibration energy harvesting applications. In this study, we present numerical results for a graphene ripple treated as a Brownian particle coupled to an energy harvesting circuit. When circuit and particle are at the same temperature, the second law forbids harvesting energy from the thermal motion of the Brownian particle, even if the circuit contains a rectifying diode. However, when the circuit contains a junction followed by two diodes wired in opposition, a special ultraslow convergence to equilibrium may be imposed. Detailed balance is temporarily broken as current flows between the two diodes and charges two storage capacitors. The harvested energy is taken from the surrounding thermal environment, and we show that the system obeys the first and second laws of thermodynamics. Experimental results will also be presented for a custom designed integrated circuit built by TSMC combined with post-processing lithography on bare die followed by graphene suspension. Figure 1

A Self-Powered DSSH Circuit with MOSFET Threshold Voltage Management for Piezoelectric Energy Harvesting.

This paper presents a piezoelectric (PE) energy harvesting circuit based on the DSSH (double synchronized switch harvesting) principle. The circuit consisted of a rectifier and a DC-DC circuit, which achieves double synchronized switch operation for the PE transducer in each vibration half-cycle. One of the main challenges of the DSSH scheme was precisely controlling the switch timing in the second loop of the resonant loops. The proposed circuit included a MOS transistor in the second loop to address this challenge. It utilized its threshold voltage to manage the stored energy in the intermediate capacitor per vibration half-cycle to simplify the controller for the DSSH circuit. The circuit can operate under either the DSSH scheme or the ESSH (enhanced synchronized switch harvesting) scheme, depending on the value of the intermediate capacitor. In the DSSH scheme, the following DC-DC circuit reused the rectifier's two diodes for a short period. The prototype circuit was implemented using 16 discrete components. The proposed circuit can be self-powered and started up without a battery. The experimental results showed that the proposed circuit increased the power harvested from the PE transducer compared to the full-bridge (FB) rectifier. With two different intermediate capacitors of 100 nF and 320 nF, the proposed circuit achieved power increases of 3.2 and 2.7 times, respectively. The charging efficiency of the proposed circuit was improved by a factor of 5.1 compared to the typical DSSH circuit.

Multimodal piezoelectric energy harvesting on a thin plate integrated with SSHI circuit: an analytical and experimental study

Multimodal piezoelectric energy harvesting can be achieved by integrating piezo-patch harvesters into plate-like structures available in marine, aerospace, and automotive applications. A synchronized switch harvesting on inductor (SSHI) interface as the harvesting circuit has been well studied for cantilever beams, considering the single vibration mode of the structure. However, integrating a two-dimensional electromechanical structure with a SSHI circuit for multimodal energy harvesting is missing in the literature. This paper evaluates the performance of the SSHI interface integrated with a piezoelectric energy harvester (PEH) on a plate-like host structure. The analytical solution is developed based on an equivalent impedance approach to predict the steady-state electrical response of the harvester as a closed-form solution. The experiments are conducted to validate the analytical solution for the system’s first and second vibration modes. The experimental results reveal that integration of SSHI to a plate-like harvester introduces a multi-switching behavior rather than a standard single-switching behavior. Due to the multimodal vibrational characteristics of the plate, the circuit switch is triggered several times at each half period of the vibration, which increases the energy dissipation of the circuit and thus reduces the output voltage. On the other hand, single switching at each half period of the vibration happens for lower piezoelectric voltage levels. This is the desired behavior of the SSHI circuit where the analytical prediction matches with the experimental data. Finally, the energy harvesting performance of the SSHI circuit is compared against the standard rectifier, showing 183% and 134% power output enhancement for the first and second vibration modes, respectively.