Cell Power Supply Research Articles

Hydrogen fuel cell power supply for hybrid electric multiple unit train

In European countries, electrified routes amount for 40% to 65% of the total railway networks length. Some of those routes are only partially electrified, and construction of a catenary network might not be viable on all routes. Consequently, operators run diesel trains under catenary or require both an electric and diesel vehicle, increasing costs of operation. Dual-mode vehicles exist, but they are mostly equipped with diesel generators, adding to the pollution and resulting in reduced movement dynamics. In this article, the authors present a hydrogen-hybrid electric multiple unit (HEMU), as an environmentally friendly vehicle for partially electrified railway lines. Insight into technologies utilized by both hybrid and hydrogen rail vehicles based on the literature review allowed for the formulation of requirements for such a vehicle. Furthermore, an approach to a modelling hybrid vehicle is described, including an energy management algorithm. A series of simulations were conducted, showing an operation of an HEMU on a partially electrified suburban/regional route. The presented simulation results show potential for the future introduction of hydrogen hybrid electric multiple units as a viable solution for partially electrified local and regional routes.

Optimization of cold startup strategy with quasi 2-D model of metal hydride hydrogen storage with fuel cell

In this work, a novel cold startup strategy is presented for a large-scale metal hydride–fuel cell system. Due to the thermal requirement of the system, when the initial temperature of metal hydride and ambient air is low, the system cannot be started because the hydrogen pressure in the metal hydrides storage system is lower than the minimal pressure required by the fuel cell. The cold startup is achieved by maintaining a part of metal hydride storage at a target temperature and using coolant control to transfer heat to the remaining cold metal hydride storage upon operation of the fuel cells. The strategy is studied numerically and a novel Quasi-2-Dimensional approach is developed to describe heat transfer within metal hydrides and validated. By the proper selection of the value of the control variable, both fast startup and immediate uninterrupted fuel cell power supply are achieved. The effect of initial conditions on the startup process is studied and the strategy consumed 30 % less energy than the alternative without control. The proposed strategy is suitable and efficient for the cold startup of large-scale metal hydride-fuel cell systems.

An electro-optic (EO) pulsed electric field sensor powered by photovoltaic cell

Considering the limitations of battery-powered active EO modulated electric field sensors, a photovoltaic cell-powered electric field sensor is designed, fabricated and experimentally demonstrated. The sensor is consisting of a laser photovoltaic cell-powered supply circuit, a receiving modulation circuit, and an induction antenna. The laser photovoltaic cell power supply circuit which composed of a power supply laser, a photovoltaic cell, and a DC-DC conversion circuit is designed and fabricated. Experimental results show that the photovoltaic cell power supply circuit can output stable voltages of 5 V and 1.2 V for the receiving modulation circuit. A lightning impulse (LEMP) measurement system is set up and used to test the characteristics of the electric field sensor in the time domain. The experimental results show that the sensor detected pulsed electric field shows good consistency with the applied LEMP in the time domain and the dynamic range of the sensor is from 0.86 kV m−1 to 10.7 kV m−1.

Techno-Economic Analysis of a Hydrogen-Based Power Supply Backup System for Tertiary Sector Buildings: A Case Study in Greece

In view of the European Union’s strategy on hydrogen for decarbonization and buildings’ decarbonization targets, the use of hydrogen in buildings is expected in the future. Backup power in buildings is usually provided with diesel generators (DGs). In this study, the use of a hydrogen fuel cell (HFC) power supply backup system is studied. Its operation is compared to a DG and a techno-economic analysis of the latter’s replacement with an HFC is conducted by calculating relevant key performance indicators (KPIs). The developed approach is presented in a case study on a school building in Greece. Based on the school’s electricity loads, which are calculated with a dynamic energy simulation and power shortages scenarios, the backup system’s characteristics are defined, and the relevant KPIs are calculated. It was found that the HFC system can reduce the annual CO2 emissions by up to 400 kg and has a lower annual operation cost than a DG. However, due to its high investment cost, its levelized cost of electricity is higher, and the replacement of an existing DG is unviable in the current market situation. The techno-economic study reveals that subsidies of around 58–89% are required to foster the deployment of HFC backup systems in buildings.

Energy management strategy for standalone DC microgrid system with photovoltaic/fuel cell/battery storage

Standalone DC microgrids often have challenges in energy management for a long time horizon due to uncertain renewable energy sources and volatile loads. This paper presents a centralized energy management strategy(EMS) for a standalone DC microgrid with solar PV, fuel cells, and a battery energy storage system (BESS). The proposed EMS method is designed to improve the longevity of BESS, reliability, and reduce the hydrogen intake. In the proposed EMS, the PV system de-rating method is used to overcome the deep charging of battery under low-demand conditions. The fuel cell power supply is varied using a reverse sigmoidal function of the Batterys state of charge (SoC). This improves the hydrogen fuel efficiency and also helps in minimizing deep discharge of the battery under heavy loading conditions. The centralized EMS is fed with load power, battery SoC, and individual source power information. Consequently, the EMS provides decisive commands to the individual source local controller to control the respective output power. The efficacy of the proposed EMS under multiple operating conditions is evaluated in both simulation environment and on a hardware prototype of a DC microgrid.

SINGLE HOP AUTHENTIC BROADCASTING IN SOCIAL MOBILE NETWORKS USING BLUETOOTH

This paper aims to create infrastructure-free networking capabilities for people in need such as when inadequate infrastructure including mobile cell towers and power supplies are damaged or when all communication means are restricted. In general, this means finding a way to communicate without mobile cell towers, repeaters, or Wi-Fi hotspots on mobile devices. This paper focuses on introducing an ad-hoc network based on Bluetooth where users can communicate without barriers. The proposed network implementation uses Google’s API Nearby Connection which is one of Google Play Services that can provide high bandwidth, low latency, encrypted data transfers between nearby devices in a fully-offline P2P mode. Kotlin language was used to program an application called BlueEmergency installed on Android devices to broadcast data as bytes payloads in a form of text messages from one node to all nodes in proximity using Bluetooth only. The test and verification of the system are performed showed that successful communication is achieved with the latest versions of both the Android operating system and Bluetooth. Finally, the designed network can be extended to cover large geographical areas by multi-hopping the messages between devices to make the system more efficient to use in the time of need.

VO2 Carbon Nanotube Composite Memristor-Based Cellular Neural Network Pattern Formation

A cellular neural network (CNN) based on a VO2 carbon nanotube memristor is proposed in this paper. The device is modeled by SPICE at first, and then the cell dynamic characteristics based on the device are analyzed. It is pointed out that only when the cell is at the sharp edge of chaos can the cell be successfully awakened after the CNN is formed. In this paper, we give the example of a 5 × 5 CNN, set specific initial conditions and observe the formed pattern. Because the generated patterns are affected by the initial conditions, the cell power supply can be pre-programmed to obtain specific patterns, which can be applied to the future information processing system based on complex space–time patterns, especially in the field of computer vision.

Comprehensive review of floc growth and structure using electrocoagulation: Characterization, measurement, and influencing factors

• Floc growth and structure are crucial for removal efficiency; however, they have attracted little attention in the electrocoagulation process. • Reported floc structure parameters, and their measurement methods, are presented in detail. • Influencing factors, including current intensity, initial p H , EC cell design, power supply, stirring pattern, and temperature, are summarized. • The development of electrode materials and coupling techniques is promising for floc performance improvement. Electrocoagulation (EC) has received significant attention for wastewater treatment owing to its environmental sustainability. The high removal efficiency of EC depends on flocs with large, strong structures. Flocs that aggregate with coagulants, pollutant particles, and fine electrolytic bubbles (10–50 μm) are complex and fragile during EC. However, floc growth during EC has not been thoroughly studied, and their structures have not been described in detail compared to the flocs formed by chemical coagulation (CC). Herein, the current research on floc growth during EC is comprehensively reviewed. First, the characteristics of flocs grown using EC are introduced. Second, the floc size, strength, and fractal geometry are described in detail, revealing the floc structure. Third, these structural parameter measurement methods, such as equivalent diameter, three-dimensional (3D) reconstruction, scattering, strength factor, and velocity gradient, are presented. Next, since particle aggregation is affected by the chemical conditions and hydrodynamics within the reactor, several factors, such as initial pH, current intensity, stirring pattern, electrode design, power supply, and temperature, impacting floc growth are summarized. Finally, future research directions are proposed for exploring the floc structures grown during EC and optimizing electrode materials, such as air cathodes and porous metallic anodes. This review may help reveal the removal mechanisms for diverse pollutants using EC and provide a future standard for EC cell design.

Pemanfaatan Solar Cell Sebagai Sumber Energi Alternatif Untuk Fasilitas Bangku Taman Ruang Terbuka Hijau


 
 
 
 The source of electricity for the Taman Tiga Generasi facility, a Green Open Space in the City of Balikpapan, is highly dependent on PLN sources, resulting in an electrical energy crisis. Also, not all parks have facilities and infrastructure such as benches for visitors to sit on. Community service aims to apply electric bench technology with solar cell electricity generation for parks and implement Appropriate Technology products for the community based on solutions to partner problems. This community service method considers the health protocol in which the process is carried out directly and is limited. The stages are (1) Application of solar cell electricity technology to provide electricity for garden facilities; (2) Training by service team for partners regarding the operation and maintenance of electrical bench products with solar cell power supply; (3) Counseling regarding the conservation of electrical energy for partners. This community service resulted in a multifunctional electric bench product as a seat, as a place to charge mobile electronic devices, and as a source of lighting for the garden area with a solar panel-based power supply. Community service activities as part of the realization of alternative solar cells for electricity generation in Indonesia in saving electrical energy.
 
 
 

Exploration of Extreme Environments with Currentand Emerging Robot Systems

The discovery of living organisms under extreme environmental conditions of pressure, temperature, and chemical composition on Earth has opened up the possibility of existence and persistence of life in extreme environment pockets across the solar system. These environments range from the many intriguing moons, to the deep atmospheres of Venus and even the giant gas planets, to the small icy worlds of comets and Kuiper Belt Objects (KBOs). Exploring these environments can ascertain the range of conditions that can support life and can also identify planetary processes that are responsible for generating and sustaining habitable worlds. These environments are also time capsules into early formation of the solar system and will provide vital clues of how our early solar system gave way to the current planets and moons. Over the last few decades, numerous missions started with flyby spacecraft, followed by orbiting satellites and missions with orbiter/lander capabilities. Since then, there have been numerous missions that have utilized rovers of ever-increasing size and complexity, equipped with state-of-the-art laboratories on wheels. Although current generations of rovers achieve mobility through wheels, there are fundamental limitations that prevent these rovers from accessing rugged environments, cliffs, canyons, and caves. These rugged environments are often the first places geologist look to observe stratification from geohistorical processes. There is an important need for new robot mobility solutions, like hopping, rolling, crawling, and walking that can access these rugged environments like cliffs, canyons, and caves. These new generations of rovers have some extraordinary capabilities including being able to grip onto rocks like NASA/JPL LEMUR 2, operate in swarms such as MIT’s microbots, or have high-specific energy fuel cell power supply that is approximately 40-fold higher than conventional lithium ion batteries to Stanford/NASA JPL’s Hedgehog which is able to hop and somersault in low-gravity environments such asteroids. All of these mobility options and supporting technologies have been proposed and developed to explore these hard-to-reach unconventional environments. This article provides a review of the robotic systems developed over the past few decades, in addition to new state-of-the-art concepts that are leading contenders for future missions to explore extreme environments on Earth and off-world.

Design and implementation of an improved sinusoidal controller for a two-phase enhanced impedance source boost inverter

This study presents a novel Sinusoidal Pulse Width Modulation (SPWM) model for a two-phase Impedance Source-based Inverter (ZSI) with a hardware prototype implementation. The high-gain feature is investigated based on an innovative mathematical model that involves fewer components and presents efficient performances. The presented topology can be applied broadly in Photo Voltaic systems, Wind Power, Fuel Cell, and Uninterrupted Power Supply topologies due to the ability of wide-range load regulation with higher duty cycles. Through Shoot (TS) and higher Total Harmonic Distortion (THD) problems can be solved by a carefully designed gate-drive circuit and proper switching frequency for the appropriate resistance against the Electromagnetic Interfaces (EMIs). One of the essential specifications of the proposed controller is working with intermediate values of duty cycles for power MOSFETs that can decrease the losses for the inverter. A set of numerical simulation and hardware results are presented for ensuring the proposed claims.

Elaboration of Chemical Hydrogen Source Based on Hydrides of Magnesium Alloys

In the present work, Mg–Ni–Mm alloys (where Mm is a mixture of rare earth metals) are studied to elaborate a chemical hydrogen source for portable energy systems based on fuel cells characterized by high gravimetric energy density used for unmanned air vehicles and robot systems. Hydrogen generation on demand by hydrolysis of metal hydrides (MgH2, Mg2NiH4) is proposed for the fuel cell power supply because it is the most efficient method characterized by high hydrogen storage density, safety, and low costs of the stored energy. The influence of the composition of alloys on the hydrogen absorption properties and hydrogen generation during hydrolysis is studied.

French ROAD project developing refrigerated semi-trailers with fuel cell power supplies

The French ROAD (Refrigerated Optimized Advanced Design) project aims to develop a new generation of refrigerated semi-trailer (articulated) trucks, utilising more economical, less polluting and quieter technologies, including the integration of a fuel cell to provide power for ‘greener’ refrigerated semi-trailers during 2019.

Design of Brake Regeneration Controller and Proton Exchange Membrane Fuel Cell Power Supply for a Robot

Design of Brake Regeneration Controller and Proton Exchange Membrane Fuel Cell Power Supply for a Robot

The design of long-life, high-efficiency PEM fuel cell power supplies for low power sensor networks

Field sensor networks have important applications in environmental monitoring, wildlife preservation, in disaster monitoring and in border security. The reduced cost of electronics, sensors and actuators make it possible to deploy hundreds if not thousands of these sensor modules. However, power technology has not kept pace. Current power supply technologies such as batteries limit many applications due to their low specific energy. Photovoltaics typically requires large bulky panels and is dependent on varying solar insolation and therefore requires backup power sources. Polymer Electrolyte Membrane (PEM) fuel cells are a promising alternative, because they are clean, quiet and operate at high efficiencies. However, challenges remain in achieving long lives due to factors such as degradation and hydrogen storage. In this work, we devise a framework for designing fuel cells power supplies for field sensor networks. This design framework utilize lithium hydride hydrogen storage technology that offers high energy density of up to 5000 Wh/kg. Using this design framework, we identify operating conditions to maximize the life of the power supply, meet the required power output and minimize fuel consumption. We devise a series of controllers to achieve this capability and demonstrate it using a bench-top experiment that operated for 5000 h. The laboratory experiments point towards a pathway to demonstrate these fuel cell power supplies in the field. Our studies show that the proposed PEM fuel cell hybrid system fueled using lithium hydride offers at least a 3 fold reduction in mass compared to state-of-the-art batteries and 3-5 fold reduction in mass compared to current fuel cell technologies.

Effect of growth solution, membrane size and array connection on microbial fuel cell power supply for medical devices.

Implanted biomedical devices typically last a number of years before their batteries are depleted and a surgery is required to replace them. A Microbial Fuel Cell (MFC) is a device which by using bacteria, directly breaks down sugars to generate electricity. Conceptually there is potential to continually power implanted medical devices for the lifetime of a patient. To investigate the practical potential of this technology, H-Cell Dual Chamber MFCs were evaluated with two different growth solutions and measurements recorded for maximum power output both of individual MFCs and connected MFCs. Using Luria-Bertani media and connecting MFCs in a hybrid series and parallel arrangement with larger membrane sizes showed the highest power output and the greatest potential for replacing implanted batteries.

Nonlinear Model Based Single-Loop Control of Interleaved Converters for a Hybrid Source System

Generally, fuel cell (FC) power supplies cannot respond fast enough to dynamic load requirements. This research presents an energy management system for hybrid power sources in dc distribution systems. A supercapacitor (SC) module was designed to be the second power source in order to supply energy in transient, which can respond well to dynamic loads. In terms of circuits, a two-phase parallel boost converter was connected to each power source for regulating the output voltage. The interleaved technique was applied for reducing the current ripples of the sources. Flatness control, which is a nonlinear estimation technique, combined with a single-loop control strategy is proposed to control the system and it responds faster than multiple-loop controls. In this research, it included a hybrid system of two power sources namely a 500-W fuel cell emulator and a 165-F supercapacitor module, each connecting to a two-phase interleaved boost converter. The control algorithm for the hybrid system was developed and validated by the MATLAB-Simulink interfacing with a dSPACE 1103 controller card. The experimental results showed the rapid response of the proposed system to the dynamic load requirement. This confirmed that the single-loop flatness control is a potential algorithm that offers stabilization of the hybrid system.

Sea water magnesium fuel cell power supply

An environmentally friendly magnesium fuel cell system using seawater electrolyte and atmospheric oxygen was tested under practical considerations for use as maritime power supply. The hydrogen rate and therefore the power density of the system were increased by a factor of two by using hydrogen evolution cathodes with a gas separation membrane instead of submerged cathodes without gas separation. Commercial magnesium AZ31 rolled sheet anodes can be dissolved in seawater for hydrogen production, down to a thickness below 100 μm thickness, resulting in hydrogen generation efficiency of the anode of over 80%. A practical specific energy/energy density of the alloy of more than 1200 Wh/kg/3000 Wh/l was achieved when coupled to a fuel cell with atmospheric air breathing cathode. The performance of several AZ31 alloy anodes was tested as well as the influence of temperature, electrolyte concentration and anode – cathode separation. The excess hydrogen produced by the magnesium hydrogen evolving cell, due to the negative difference effect, is proportional to the cell current in case of the AZ31 alloys, which simplifies system control considerably. Stable long-term operation of the system was demonstrated at low pressures which can be maintained in an open-seawater-submerged hydrogen generator.

State of Health estimation for NCA-C Lithium-ion cells

The Lithium-ion batteries suffer from several aging phenomena, which imply a battery performance degradation, i.e. decreasing in energy storage capacity and power supply capability. For the electrified vehicles, monitoring the health of the battery pack is a necessary task that can prevent the system defaults, alert for anomalies, and predict the battery end-of-life (EOL). This paper presents a two-phase cell state of health (SOH) estimation strategy, depending on the cell current demand. The cell energy storage capacity is identified when the battery is at rest while the cell power supply capability is identified during the cell cycling.

Current-Fed Switched Inverter

High-boost dc-ac inverters are used in solar photovoltaic (PV), fuel cell, wind energy, and uninterruptible power supply systems. High step-up and step-down capabilities and shoot-through immunity are some of the desired properties of an inverter for a reliable, versatile, and low-distortion ac inversion. The recently developed Z-source inverter (ZSI) possesses these qualities. However, the realization of ZSI comes at a cost of higher passive component count as it needs two sets of passive filters. A switched boost inverter (SBI) has similar properties as ZSI, and it has one L-C pair less compared to ZSI, but its gain is less than ZSI. This paper proposes the current-fed switched inverter (CFSI) which combines the high-gain property of ZSI and low passive component count of SBI. The proposed inverter uses only one L-C filter and three switches apart from the inverter structure. The inverter topology is based on current-fed dc/dc topology. Steady-state analysis of the inverter is presented to establish the relation between the dc input and the ac output. A pulse width modulation (PWM) control strategy is devised for the proposed inverter. An experimental prototype is built to validate the proposed inverter circuit in both buck and boost modes of operation. A 353-V dc-link and a 127 V (rms) ac are obtained from a 35.3-V dc input to demonstrate the boost mode of operation. A 200-V dc-link and a 10.5-V (rms) ac are obtained from a 37.8-V dc input to verify the buck mode of operation of CFSI.