Multifunctional Power Research Articles

A solar-powered multi-functional portable charging device (SPMFPCD) with internet-of-things (IoT)-based real-time monitoring—An innovative scheme towards energy access and management

In the absence of portable charging devices, sectors such as transportation, communication, and emergency services deal with various challenges towards electric power needs while compromising on (1) operational efficiency, (2) insufficient portable charging solutions, and (3) limited versatility. This highlights the critical need for reliable and multi-functional power solutions. To provide a portable charging solution across diverse sectors, this paper proposes an innovative development of a solar-powered multi-functional portable charging device (SPMFPCD) with internet- of-thing (IoT)-based monitoring capabilities. The proposed scheme introduces a comprehensive model integrating advanced technologies which include a highly efficient solar panel, charge controller, sensors, and IoT module. The proposed system facilitates versatile charging solutions for a wide range of power requirements with real-time monitoring and data analysis through the IoT platform. Moreover, the proposed work explores the applications of the SPMFPCD in (1) emergency medical scenarios, (2) outdoor adventures, (3) disaster management, and 4) public spaces. Performance evaluation was made by proposing case studies to validate the (1) economic viability, (2) power management, and (3) environmental impact of widespread deployment of SPMPFCD in public spaces. Furthermore, detailed analysis of battery energy storage system (BESS) and photovoltaic (PV) integration for load management, seasonal dynamics, and renewable energy integration (REI) contribute to a comprehensive understanding of the proposed solution.

Flexible energy storage device fabricated by electrochromic smart copolymer based on thienothiophene-triphenyamine and EDOT

Sustainable energy storage materials are of increasing importance for new energy technologies to produce more intelligent, lighter, thinner and multifunctional power systems. In this study, copolymers of N-(4-(4-thieno[3,2-b]thiophene-3-ylphenyl)phenyl)-N-phenylbenzenamine (TTpTPA) and 3,4-ethylenedioxythiophene (EDOT) were synthesized electrochemically starting from different molar ratios of TTpTPA(T) and EDOT(E) (nT:nE). The copolymers obtained on the ITO surface, i.e. P(T10-1E), P(T5-1E), P(T5-2E), P(T1-1E), were directly used to design electrochromic energy storage devices (ECESDs). Electrochemical characterizations suggested that the copolymerization improved the capacitances of PTTpTPA and PEDOT up to the highest value of 21 mF cm−2 with the copolymer P(T1-1E). It exhibited a color change from purple to blue during charging and discharging processes. Additionally, P(T5-2E) displayed a remarkable multicolor change as a color cartel, i.e. red, yellow, green, gray and blue, during the oxidation with a high color efficiency of 161 cm2C−1. Finally, the flexible symmetric device prototype of P(T1-1E) possessed a good practical application for next generation energy storage devices with its high energy and high-power densities.

Anionic Chemistry Modulation Enabled Environmental Self-Charging Aqueous Zinc Batteries: The Case of Carbonate Ions.

Anionic chemistry modulation represents a promising avenue to enhance the electrochemical performance and unlock versatile applications in cutting-edge energy storage devices. Herein, we propose a methodology that involves anionic chemistry of carbonate anions to tailor the electrochemical oxidation-reduction reactions of bismuth (Bi) electrodes, where the conversion energy barrier for Bi (0) to Bi (III) has been significantly reduced, endowing anionic full batteries with enhanced electrochemical kinetics and chemical self-charging property. The elaborately designed batteries with an air-switch demonstrate rapid self-recharging capabilities, recovering over 80 % of the electrochemical full charging capacity within a remarkably short timeframe of 1 hour and achieving a cumulative self-charging capacity of 5 Ah g-1. The aqueous self-charging battery strategy induced by carbonate anion, as proposed in this study, holds the potential for extending to various anionic systems, including seawater-based Cl- ion batteries. This work offers a universal framework for advancing next-generation multi-functional power sources.

Design of an Enhanced Dynamic Regulation Controller Considering the State of Charge of Battery Energy Storage Systems

In recent years, the escalating electricity demand in Taiwan has heightened the prominence and discourse surrounding the issue of power supply. With the enactment of the European climate law, global commitment to achieving net-zero emissions has gained momentum. Concurrently, the Taiwanese government has articulated the Taiwan 2050 net-zero emissions policy. To realize this objective, Taiwan has vigorously promoted renewable energy in recent years, increasing the proportion of renewable energy in its energy mix. However, confronted with the intermittent and unpredictable nature of renewable energy generation, challenges arise concerning the stability and quality of power supply. In response to the impact of integrating renewable energy into the grid, the Taiwan Power Company (Taipower) has introduced the day-ahead ancillary service market. Through this platform, power generation and battery energy storage systems (BESSs) engage in competitive bidding, fostering the integration of diverse distributed energy resources into the system. These resources serve as dispatchable assets for Taipower, contributing to grid stability by providing ancillary services. This study has developed an advanced dynamic regulation reserve controller by employing an industrial PC (IPC) in conjunction with a multifunctional power meter. Through real-time measurement of the power grid frequency by the multifunctional power meter, a sophisticated dynamic frequency reserve control strategy has been devised, taking into account the charging state of energy storage systems. This strategy exhibits high operational quality, effectively regulating the charging and discharging of energy storage systems. In addition to swiftly adjusting the current grid frequency, it encompasses the capability to facilitate the transfer of peak electrical energy. This effectively stabilizes the power grid, alleviating supply pressures during nighttime peaks and enhancing the overall supply stability of the power system.

A Compact Multifunctional Power Electronic Interface for Plug-In Hybrid Electric Vehicles Using IoT

Abstract: The main objective of this endeavor is to construct a hybrid electric vehicle that recharges its battery using a range of electrical energy sources, such as solar, wind, and dynamo power using multifunctional power electronic sources. These are the forms of renewable energy that regenerate more quickly than they exhaust. Voltage sensors are attached to the PIC microcontroller, battery, solar panel, wind turbine, and dynamo in order to measure voltages. This measured voltage will be displayed on an LCD, and embedded C language will be used to upload the values, along with the date and time using ESP8266 WIFI-Module, to the THINGSPEAK cloud. This project's primary goals are to use rechargeable batteries to store source energy from solar, wind and dynamo power in an electric vehicle (EV) while using THINGSPEAK to monitor and record data, and update the LCD display with measured voltages

Development and application of power head for CBM vehicle mounted drilling rig

In order to meet the construction needs of surface coalbed methane extraction holes, cable holes, and mine surface rescue holes, a multifunctional power head suitable for coalbed methane vehicle mounted drilling rigs has been developed. The power head adopts a dual speed hydraulic motor to drive the spindle rotation through a first gear reduction, with a compact structure, high transmission efficiency, large spindle diameter, wide range of speed and torque adjustment, and spindle braking function. It can be applied to various drilling processes such as air down the hole hammer, air lift reverse circulation, and directional drilling. On site tests have shown that the power head has high capacity, efficiency, comprehensive functions, and is easy to operate, providing equipment support for efficient and safe drilling construction.

Research on environmental and resource benefits of offshore multifunctional power generation platform

With the development of science and technology, land resources have been over-exploited and cannot meet the needs of development, so people gradually turn to the ocean for development. The ocean not only occupies two thirds of the earth, but also contains a variety of rich resources. They not only meet people's huge demand for energy, but also most of the resources in the ocean are green and renewable energy, which not only reduces the cost of resource development to a certain extent, but also reduces the impact on the environment in the development process. An offshore multifunctional power generation platform is designed in this paper. The impact of chemical substances produced when the anti-corrosion coating on the surface of the platform on the Marine environment is analysed. Compared with the construction cost of offshore resources development, the reduction of carbon emissions and the impact of offshore platforms on the marine environment were studied respectively. The final cost per kw of the platform is at the average level of an offshore power generation project. Carbon emission reduction is much less than traditional onshore power generation projects. The pollution to the marine environment is also within the provisions of the marine pollution index.

Power Loss Analysis with Dispersed Generation in Multifunction Power Conditioner Design to Improve Power Quality

The recent modification in utilizing Multifunction Power Conditioner (MPC) such as Unified Power Quality Conditioner devices in power systems has led to different degrees of power losses, owing to electronic power impacts. This paper presents a detailed comparison of power loss analysis in various configurations of MPC, that is, the conventional unified power quality conditioner (UPQC) and the UPQC with distributed generation (〖UPQC〗_DG). The independent losses based on inverter design and distributed generation interfacing to the distribution form the basis for each configuration case. The investigation considered conventional UPQC as the base case for power losses, and the study was extended to 〖UPQC〗_DG at steady state operating condition. In all configurations, Switching Losses (SL) and conduction losses were considered using simulation studies carried out in MATLAB/SIMULINK, and the results obtained in all cases were used for comparative studies. Finally, the outcome indicates that the losses in 〖UPQC〗_DG is more than conventional UPQC based on simulation results in all cases.

Self-powered transformer intelligent wireless temperature monitoring system based on an ultra-low acceleration piezoelectric vibration energy harvester

The wireless sensor nodes used for monitoring the condition of grid equipment always be powered by disposable batteries. However, it introduces disadvantages, such as inconvenient replacement, short lifespan, and environmental pollution, significantly impeding the development of smart grids. Here, a high-performance piezoelectric vibration energy harvester (PVEH) is employed to the wireless monitoring system as the new intelligent equipment for grids. The system primarily consists of a double-crystal PVEH; a multi-functional power management circuit (PMC) with maximum energy extraction, battery replenishment, and cold-start; a module for temperature sensing; and a micropower wireless section. The results show that the PVEH reaches an output voltage of 0.7 V under 0.02 g, which has ultra-low activation acceleration compared to other double-crystal PVEH. The PVEH with an integrated PMC can charge a 680-μF capacitor to 3.3 V in 120 s, demonstrating over a 33.3% reduction in the charging time and a 50% enhancement in the charging efficiency. Moreover, the energy harvesting via the system can trigger the sensor once per 25 s, allowing the sensor to continue working and achieving the goal of intelligent monitoring. This study establishes a theoretical and experimental basis for PVEH-based sensor systems in the grid, thereby accelerating the application and commercialization of PVEH.

Janus carbon nitride membrane for robust and enhanced nanofluidic power generation from wastewater

Nanofluidic membranes have shown great promise in harvesting osmotic power. Yet, previous studies extensively focused on osmotic energy released by the mixing of seawater and river water, while there exist many other osmotic energy sources, such as the mixing of wastewater with other water. However, harvesting the osmotic power of wastewater is highly challenging because it requires the membranes to have environmental remediation capabilities to avoid pollution and biofouling, which has not been satisfied by previous nanofluidic materials. In this work, we demonstrate that a Janus carbon nitride membrane can be used for simultaneous power generation and water purification. The Janus structure of the membrane generates asymmetric band structure and therefore a built-in electric field, facilitating electron-hole separation. As a result, the membrane shows strong photocatalytic capability, which efficiently degrades organic pollutants and kills microorganisms. In particular, the built-in electric field also facilitates ionic transport, significantly promoting the osmotic power density up to 30 W/m2 under simulated sunlight illumination. The power generation performance can be robustly kept with or without the presence of pollutants. This study will shed light on the development of multi-functional power generation materials for the comprehensive utilization of industrial wastewater as well as domestic sewage.

Design and Implementation of an Integrated Control Scheme for GaN-Based Multiple Power Converters

In response to the rapid changes in the international energy environment, developing renewable energy (RE)-based distributed generation (DG) and various smart micro-grid systems is crucial for creating a robust electric power grid and new energy industries. In this aspect, there is an urgent need to develop hybrid power systems suitable for coexistent AC and DC power grids, integrated by high-performance wide ban gap (WBG) semiconductor-based power conversion interfaces and advanced operating and control strategies. Due to the intrinsic feature of variation in RE-based power generation, the design and integration of energy storage devices, real-time regulation of power flow, and intelligent energy control schemes are key technologies for further promoting DG systems and micro-grids. This paper investigates an integrated control scheme for multiple GaN-based power converters in a small- to medium-capacity, grid-connected, and RE-based power system. This is the first time that a complete design case demonstrating three GaN-based power converters with different control functions integrated with a single digital signal processor (DSP) chip to achieve a reliable, flexible, cost effective, and multifunctional power interface for renewable power generation systems is presented. The system studied includes a photovoltaic (PV) generation unit, a battery energy storage unit, a grid-connected single-phase inverter, and a power grid. Based on system operation condition and the state of charge (SOC) of the energy storage unit, two typical operating modes and advanced power control functions are developed with a fully digital and coordinated control scheme. Hardware of the GaN-based power converters and digital controllers are designed and implemented. The feasibility and effectiveness of the designed controllers and overall performance of the proposed control scheme are verified with results from simulation and experimental tests on a 1-kVA small-scale hardware system.

A multi-functional converter based switched reluctance motor drive for electric vehicle

<span>Owing to the resilience and ease of control, switched reluctance motors are commonly utilized in electric vehicle drives. This paper provides a topology for a multi-functional power converter for switched reluctance motor based electric vehicle drive with driving, braking and charging potentialities. With efficient control algorithms, a single power electronic converter is used for motoring, regenerative braking, and charging of the battery bank, resulting in a cost-effective power electronic interface. The front-end voltage control and current control of the switched reluctance motor (SRM) are used to achieve open loop and closed loop speed control during driving mode. Re-generation is made possible through restricted switching of phases in negative torque region. A bridgeless rectifier converter is built in battery charging mode by combining the SRM's two-phase windings with the prevailing power devices of an integrated power converter, eliminating the need for additional inductors and charging units. Simulations are run in MATLAB/Simulink, and simulation results are used to validate the control schemes for all modes.</span>

Development of strength abilities of female students by means of fitness in the system of additional education

The article considers the effectiveness of purposeful development of power abilities of students in classes of the general physical training by means of fitness, who are enrolled in programs of the secondary vocational education. As a means of developing strength abilities, it is proposed to include in training sessions the exercises burdened with the weight of own body 2 times a week for 6 months (static and dynamic), exercises with the weight of external objects and exercises with special fitness equipment and equipment (TRX loops, step platform, BOSU, fitball, multi-functional power frame) under the method of circular training. The purpose of the study is to experimentally determine the effectiveness of the developed method of developing power abilities. The study involved 70 female students (n = 70) divided into two groups. The first group was engaged in the general physical training sessions 2 times a week using traditional means of developing strength abilities. The second group was engaged in a specially developed method using nontraditional means of fitness for the development of strength abilities. According to the results of the study, a positive effect was determined, which is expressed in a significantly higher increase in results in control tests for evaluating power abilities in the experimental group. Thus, the pedagogical experiment showed the effectiveness of the proposed method of purposeful development of strength abilities by means of fitness in the system of additional education. The results of testing the level of strength training in the experimental group according to our proposed method turned out to be quite high. The use of different areas of strength fitness in sectional activities, which gives a significant increase in the development of girls' strength abilities (p<0.05). The average results of the experimental group increased from 11.2 to 24.4%.

Design of a compact multifunctional power divider loaded with short‐ended stub

Design of a compact multifunctional power divider loaded with short‐ended stub

When Do Chief Digital Officers Matter? An Examination of CDO Power and Firm Performance

Incumbent firms have been increasingly appointing a Chief Digital Officer (CDO) to centrally manage and coordinate digital transformation endeavors. While extant research focuses on understanding the responsibilities of CDOs, we know only little about whether and how different CDO role designs influence firm performance. Integrating upper echelons theory with the managerial power literature, we theorize on and empirically investigate the influence of CDO power on firm performance. Our sample consists of 321 CDOs that represent 286 firms from the S&P 500 and STOXX Europe 600 indices from 2010 to 2019. In line with our hypotheses, we find that CDO multifunctional power and expertise power positively influence firm performance. Moreover, while our results reveal that, in contrast to our expectations, CDO hierarchical power negatively influences firm performance, we find that it serves as an important contingency factor that amplifies the positive effects of CDO multifunctional and expertise power on firm performance. We advance the managerial power literature in the context of digital transformation and provide guidance on the role design of CDOs.

Silicone Oil Emulsions As Oxygen Enriched Flow Battery Catholytes That Enable Fully Submerged Air Cathodes

In biology, multifunctional interconnected systems provide increased system-level efficiency. Animal circulatory systems, for example, transport oxygen and nutrients while simultaneously regulating temperature and maintaining homeostasis. Inspired by biology, recent work has shown how multifunctional fluids can increase the total energy density of a robotic fish by both storing electrochemical energy and transmitting mechanical work to hydraulic actuators1. Despite the low energy density of the zinc-iodide electrolytes, this multifunctional approach increased the robot energy density by 4X compared to the same robot with just a lithium-ion battery. New low viscosity fluids that can store large amounts of electrochemical energy would enable even further improvements in energy density and transform the way robots and vehicles are designed.We have created a liquid electrolyte capable of storing large amounts of dissolved oxygen that can be directly reduced with a fully submerged electrode (See Fig. 1A, 1D). This capability mimics biological circulatory systems that store oxygen in hemoglobin suspended in blood, and also takes advantage of the high energy density of redox pairs that reduce oxygen in the cathode, such as metal-air batteries. Our electrolyte is a silicone oil emulsion suspended in 0.5 M KOH (1:4 v/v with Span-60 (sorbitane monostearate) (1.0 % w/v) as a surfactant). Here, the high oxygen solubility of the silicone oil droplets (up to 2247 mg O2/L) acts like hemoglobin and increases the oxygen solubility of the entire emulsion to 30 mg O2/L compared to 6.2 mg O2/L for 0.5 M KOH. The approach of storing oxygen in emulsions was inspired by synthetic blood that can support the respiration needs of animals in emergencies. These emulsions can remain stable for several weeks and, once saturated, can maintain their high dissolved oxygen levels.The heterogeneous nature of this catholyte is essential for electrochemical energy conversion. Within the electrolytic emulsion, droplets of silicone oil are dispersed throughout aqueous potassium hydroxide. The oil phase provides oxygen for the oxygen reduction reaction while the aqueous phase provides ionic conductivity. Thus, oxygen reduction occurs at the three-phase interface between the platinum-carbon electrode, the silicone oil droplets, and the aqueous potassium hydroxide (see Fig. 1C). Importantly, all three interfaces are either solid or liquid.Cyclic voltammograms (CV) comparing the performance of electrolytes with and without silicone oils demonstrated that oxygen can be electrochemically reduced in both systems. For both samples, cyclic voltammogram scans were recorded with a fully submerged platinum-carbon working electrode at a scan rate of 5 mV/s (see Fig. 1E). The aqueous system without the silicone oil emulsions, showed weaker CV peaks and more capacitive current (see Fig. 1D). The sample with the silicone oil emulsions demonstrated a more prominent reduction peak at 0.056 V vs. SHE which is indicative of the oxygen reduction reaction in basic media (see Fig. 1D).Both electrolytes were used in a full cell set-up to demonstrate the discharge performance of a zinc-air flow battery with an underwater air cathode. While both cells had a starting open circuit voltage of ~1V, the cell without silicone oil emulsions showed a steep drop in voltage to below 0.3V after only 43 minutes. The cell with silicone oil emulsions demonstrated significantly higher discharge capacity, discharging for over 10 hours at 50 µA (0.0625 mA/cm2). The increased oxygen content in the emulsion-based catholyte is critical for superior discharge performance.This work presents a new way for storing and transporting oxygen in pumpable electrolytes. The high oxygen solubility of silicone oil emulsions allows high-rate ORR over longer durations than control electrolytes. This electrolyte is a promising candidate for multifunctional power systems and presents new design opportunities for flow batteries by removing the need for the challenging gas-liquid-solid interfaces in conventional ORR cathodes.Reference: C. A. Aubin et al., Nature, 571, 51–57 (2019) https://doi.org/10.1038/s41586-019-1313-1. Figure 1

BESS frequency regulation strategy on the constraints of planned energy arbitrage using chance-constrained programming

Battery energy storage systems (BESS) are regarded as a multi-functional power system participator, participating in the energy arbitrage strategy (EAS), the frequency regulation strategy (FRS) and so on. However, the existing BESS mainly make profit from the EAS instead of the FRS in many countries such as China. Because there is no appropriate control strategy for BESS, when the developing ancillary services market cannot price the contribution of BESS in FRS. Meanwhile, BESS do have redundant power and capacity, if only the EAS is applied. Therefore, it is significant that BESS are involved in the FRS, that the EAS has the priority in BESS utilization. In this paper, a frequency regulation strategy for the user-side BESS is proposed, on the constraints of the planned energy arbitrage. Specifically, the chance-constrained programming is applied to solve the randomness of frequency regulation requirement, ensuring the BESS profit from the EAS. Also, the exiting BESS are fully used with extra profit from FRS. At last, the promising results prove the advantages of the proposed FRS.

An Overview of Soft Open Points in Electricity Distribution Networks

Soft open points (SOPs) are power electronic devices that are usually placed at normally open points of electricity distribution networks to provide flexible power control to the networks. This paper gives a comprehensive overview of both academic research and industrial practice on SOPs in electricity distribution networks. The topologies of SOPs as multi-functional power electronic devices are identified and compared, which include back-to-back voltage source converters, multi-terminal voltage source converters, unified power flow controllers, and direct AC-to-AC modular multilevel converters. The academic research is reviewed in three aspects, i.e., benefit quantification, control, and optimal siting and sizing of SOPs. The benefit quantification indices are categorized into feeder load balancing, voltage profile improvement, power losses reduction, three-phase balancing and DG hosting capacity enhancement. The control of SOPs is summarized as a three-level control structure, where the system-level and converter-level control are further discussed. For optimal siting and sizing of SOPs, problem formulation and solution methods are analyzed. Besides the academic research, practical industrial projects of SOPs worldwide are also summarized. Finally, opportunities of research and industrial application of SOPs are discussed.

A new configuration of grid‐connected photovoltaic‐based multifunctional power converter for single‐phase system

SummaryThe paper presents a new configuration of a grid‐connected converter centering on the needs of voltage‐sensitive nonlinear loads with source current compensation and photovoltaic (PV) power injection capability. The presented system consists of a six‐switch converter, which gives dual single‐phase output. The first output is connected in shunt near the source end to inject PV‐generated power along with the supply of load current harmonics and reactive power. The second output forms a series connection near the load end to protect the voltage‐sensitive nonlinear load from supply‐side voltage variations such as sags and harmonics. The system operation is validated through MATLAB simulation and real‐time simulation using Opal‐RT (OP4510) under different dynamic conditions such as variations in supply voltage, variation in solar irradiance, and load variation which is typically encountered in a modern distribution network. The performance of the proposed multifunctional converter is found to be satisfactory in all operating conditions by meeting the desired PV power injections along with the compensation of sensitive nonlinear load terminal voltage and source current harmonic issues within the standard allowable limit specified by IEEE.

Unified power quality control based microgrid for power quality enhancement using various controlling techniques

This research analyses the introduction of unified power quality control (UPQC) to mitigate the power quality problems, which is caused by using power electronics devices. In this article, the challenges in power quality, the suggested UPQC control approaches that are made by the distributed generation of dynamic voltage restorer (DVR) and static synchronous compensator (STATCOM) with the DC-link. The DVR is a series active power filter (APF) compensator and the STATCOM is a shunt APF compensator. In the meanwhile, DVR compensates voltage related issuesas well as STATCOM provides the needed reactive power supply by load and reducing the current issues associated with the unity power factor. The main objectives of the UPQC to mitigate voltage imbalance, harmonics, negative-sequence current and reactive power. To overcome the PQ issues the multifunction power conditioner is implemented. In addition, several proposed control approaches were employed and compared with series and shunt APFs. In MATLAB/Simulink software is used to illuminate the performance of the control strategies. Finally, the simulation will be evaluated and PQ problems in UPQC will be reduced by various techniques such as unit vector template generation technique (UVTGT), power balancing theory (BPT), proportional integral (PI) control technique and hysteresis control technique.