Types Of Energy Storage Systems Research Articles

Review and Evaluation of Reinforcement Learning Frameworks on Smart Grid Applications

With the rise in electricity, gas and oil prices and the persistently high levels of carbon emissions, there is an increasing demand for effective energy management in energy systems, including electrical grids. Recent literature exhibits large potential for optimizing the behavior of such systems towards energy performance, reducing peak loads and exploiting environmentally friendly ways for energy production. However, the primary challenge relies on the optimization of such systems, which introduces significant complexities since they present quite dynamic behavior. Such cyberphysical frameworks usually integrate multiple interconnected components such as power plants, transmission lines, distribution networks and various types of energy-storage systems, while the behavior of these components is affected by various external factors such as user individual requirements, weather conditions, energy demand and market prices. Consequently, traditional optimal control approaches—such as Rule-Based Control (RBC)—prove inadequate to deal with the diverse dynamics which define the behavior of such complicated frameworks. Moreover, even sophisticated techniques—such as Model Predictive Control (MPC)—showcase model-related limitations that hinder the applicability of an optimal control scheme. To this end, AI model-free techniques such as Reinforcement Learning (RL) offer a fruitful potential for embedding efficient optimal control in cases of energy systems. Recent studies present promising results in various fields of engineering, indicating that RL frameworks may prove the key element for delivering efficient optimal control in smart buildings, electric vehicle charging and smart grid applications. The current paper provides a comprehensive review of RL implementations in energy systems frameworks—such as Renewable Energy Sources (RESs), Building Energy-Management Systems (BEMSs) and Electric Vehicle Charging Stations (EVCSs)—illustrating the benefits and the opportunities of such approaches. The work examines more than 80 highly cited papers focusing on recent RL research applications—between 2015 and 2023—and analyzes the model-free RL potential as regards the energy systems’ control optimization in the future.

Techno-Economic Analysis and Optimization of a Compressed-Air Energy Storage System Integrated with a Natural Gas Combined-Cycle Plant

To address the rising electricity demand and greenhouse gas concentration in the environment, considerable effort is being carried out across the globe on installing and operating renewable energy sources. However, the renewable energy production is affected by diurnal and seasonal variability. To ensure that the electric grid remains reliable and resilient even for the high penetration of renewables into the grid, various types of energy storage systems are being investigated. In this paper, a compressed-air energy storage (CAES) system integrated with a natural gas combined-cycle (NGCC) power plant is investigated where air is extracted from the gas turbine compressor or injected back into the gas turbine combustor when it is optimal to do so. First-principles dynamic models of the NGCC plant and CAES are developed along with the development of an economic model. The dynamic optimization of the integrated system is undertaken in the Python/Pyomo platform for maximizing the net present value (NPV). NPV optimization is undertaken for 14 regions/cases considering year-long locational marginal price (LMP) data with a 1 h interval. Design variables such as the storage capacity and storage pressure, as well as the operating variables such as the power plant load, air injection rate, and air extraction rate, are optimized. Results show that the integrated CAES system has a higher NPV than the NGCC-only system for all 14 regions, thus indicating the potential deployment of the integrated system under the assumption of the availability of caverns in close proximity to the NGCC plant. The levelized cost of storage is found to be in the range of 136–145 $/MWh. Roundtrip efficiency is found to be between 74.6–82.5%. A sensitivity study with respect to LMP shows that the LMP profile has a significant impact on the extent of air injection/extraction while capital expenditure reduction has a negligible effect.

Analysis of Voltage Control Strategies for DC Microgrid with Multiple Types of Energy Storage Systems

Direct-current (DC) microgrids have gained worldwide attention in recent decades due to their high system efficiency and simple control. In a self-sufficient energy system, voltage control is an important key to dealing with upcoming challenges of renewable energy integration into DC microgrids, and thus energy storage systems (ESSs) are often employed to suppress the power fluctuation and ensure the voltage stability. In this paper, the performances of three voltage control strategies for DC microgrids are compared, including the proportion integration (PI) control, the fuzzy PI control and particle swarm optimization (PSO) PI control. Particularly, two kinds of ESSs including battery and advanced adiabatic compressed air energy storage (AA-CAES) with different operational characteristics are installed in the microgrid, and their impacts on voltage control are investigated. The control performances are comprehensively compared under different control schemes, various scenarios of renewable energy fluctuations, participation in the control of the two ESSs or not, and different fault conditions. Additionally, the dynamic performances of the ESSs are exhibited. The results verify the validity of the control schemes and the feasibility of the configuration of the ESSs into the DC microgrid.

Hybrid Energy Storage Systems Based on Redox-Flow Batteries: Recent Developments, Challenges, and Future Perspectives

Recently, the appeal of Hybrid Energy Storage Systems (HESSs) has been growing in multiple application fields, such as charging stations, grid services, and microgrids. HESSs consist of an integration of two or more single Energy Storage Systems (ESSs) to combine the benefits of each ESS and improve the overall system performance, e.g., efficiency and lifespan. Most recent studies on HESS mainly focus on power management and coupling between the different ESSs without a particular interest in a specific type of ESS. Over the last decades, Redox-Flow Batteries (RFBs) have received significant attention due to their attractive features, especially for stationary storage applications, and hybridization can improve certain characteristics with respect to short-term duration and peak power availability. Presented in this paper is a comprehensive overview of the main concepts of HESSs based on RFBs. Starting with a brief description and a specification of the Key Performance Indicators (KPIs) of common electrochemical storage technologies suitable for hybridization with RFBs, HESS are classified based on battery-oriented and application-oriented KPIs. Furthermore, an optimal coupling architecture of HESS comprising the combination of an RFB and a Supercapacitor (SC) is proposed and evaluated via numerical simulation. Finally, an in-depth study of Energy Management Systems (EMS) is conducted. The general structure of an EMS as well as possible application scenarios are provided to identify commonly used control and optimization parameters. Therefore, the differentiation in system-oriented and application-oriented parameters is applied to literature data. Afterwards, state-of-the-art EMS optimization techniques are discussed. As an optimal EMS is characterized by the prediction of the system’s future behavior and the use of the suitable control technique, a detailed analysis of the previous implemented EMS prediction algorithms and control techniques is carried out. The study summarizes the key aspects and challenges of the electrical hybridization of RFBs and thus gives future perspectives on newly needed optimization and control algorithms for management systems.

The energy storage mathematical models for simulation and comprehensive analysis of power system dynamics: A review. Part i

Energy storage systems are increasingly used as part of electric power systems to solve various problems of power supply reliability. With increasing power of the energy storage systems and the share of their use in electric power systems, their influence on operation modes and transient processes becomes significant. In this case, there is a need to take into account their properties in mathematical models of real dimension power systems in the study of various operation modes, design, etc. In this article the main types of energy storage devices, as well as the fields and applications of their use in electric power systems are considered. The principles of realization of detailed mathematical models, principles of their control systems are described for the presented types of energy storage systems. The article is an overview and can help in choosing a mathematical model of energy storage system to solve the necessary tasks in the mathematical modeling of storage systems in electric power systems.Information is presented on large hydrogen energy storage units for use in the power system.

Experimental investigation of starting-up, energy-saving, and emission-reducing performances of hybrid supercapacitor energy storage systems for automobiles

Improvements in engine starting-up performance, such as reducing fuel consumption and exhaust emission pollution during the startup process, are very vital to achieve the national development goal of carbon peaking and carbon neutrality. Hybrid supercapacitor (HSC) energy storage systems containing batteries and supercapacitors (SCs) are considered promising energy storage strategies to compensate for the disadvantages of a single energy storage technology. In this paper, two kinds of novel 12 V/50 Ah and 12 V/70 Ah module-level energy storage systems composed of cell-level 3.6 V/2200 F HSCs were first designed. Analysis on their fundamental electrochemical properties under room temperature conditions was also performed. Four different types of energy storage systems composed of 12 V/70 Ah lithium iron phosphate (LFP) batteries, 12 V/70 Ah valve-regulated lead-acid (VRLA) batteries, and the aforementioned HSCs were then employed to compare their starting energy, energy-saving, and emission-reduction characteristics. Additionally, the 12 V/70 Ah HSC module saved 7.82 %, 3.18 %, and 1.65 % of fuel as compared to the 12 V/70 Ah VRLA, 12 V/70 Ah LFP, and 12 V/50 Ah HSC modules, respectively, demonstrating its superior fuel economy property. Simultaneously, the volume concentration of HC and CO emission in the startup process are 12.7 % and 13.2 % lower than that average of the other three modules, respectively, which shows a good exhaust emission reduction effect. The proposed energy storage system will provide systematic experimental data support and valuable theoretical guidance for the industrialization and application of HSCs.

Integration of metal hydride reactor with thermocline based heat storage system

The wide range of operating temperature and exothermic/endothermic behaviour of metal hydrides during hydrogen absorption/desorption make them suitable for various applications. The heat generated during absorption is removed by various methods and then generally this heat is dissipated in atmosphere. In this study, the metal hydride reactor using LaNi5 as metal hydride is integrated with thermocline type of energy storage system using water as storage material to store the heat generated during absorption inside metal hydride reactor and then utilize this heat during desorption process. The heat is transferred from and to the metal hydride reactor by heat transfer fluid (water) flowing through helical tube embedded inside both the reactors. A 3-D mathematical model is developed and simulated to effectively study this integrated system. The effect of supply pressure during charging, stratification and discharging process on various performance parameters are analyzed. Further, this study is extended to perform the energy analysis of this integrated system for detailed performance evaluation. The results show that the energy generated inside the metal hydride reactor was successfully stored by thermocline energy storage system with a storage efficiency of 81.7 % when the supply pressure was 16 bar. Similarly, the thermocline energy system successfully delivers 60 % of the required heat to metal hydride reactor during desorption process with a discharging efficiency of more than 70 %. The results prove that these types of integrated systems are quite promising candidate for their use in various stationary applications.

Review on Recent Strategies for Integrating Energy Storage Systems in Microgrids

Energy security and the resilience of electricity networks have recently gained critical momentum as subjects of research. The challenges of meeting the increasing electrical energy demands and the decarbonisation efforts necessary to mitigate the effects of climate change have highlighted the importance of microgrids for the effective integration of renewable energy sources. Microgrids have been the focus of research for several years; however, there are still many unresolved challenges that need to be addressed. Energy storage systems are essential elements that provide reliability and stability in microgrids with high penetrations of renewable energy sources. This study provides a systematic review of the recent developments in the control and management of energy storage systems for microgrid applications. In the early sections, a summary of the microgrid topologies and architectures found in the recent literature is given. The main contributions and targeted applications by the energy storage systems in the microgrid applications is defined for each scenario. As various types of energy storage systems are currently being integrated for the reliable operation of the microgrids, the paper analyses the properties and limitations of the solutions proposed in the recent literature. The review that was carried out shows that a hybrid energy storage system performs better in terms of microgrid stability and reliability when compared to applications that use a simple battery energy storage system. Therefore, a case study for a DC microgrid with a hybrid energy storage system was modelled in MATLAB/Simulink. The presented results show the advantages of hybrid energy storage systems in DC microgrids.

Research on Dynamic Reserve and Energy Arbitrage of Energy Storage System

Replacing the traditional rotating generators with renewable energy will reduce the grid’s inertia and with it the minimum frequency when N-1 contingency occurs triggering an Under-Frequency Load Shedding (UFLS). This study proposes a method for the energy storage system (ESS) to simultaneously provide energy arbitrage, reserve capacity, and assist N-1 contingency, by modifying the restriction formula of economic dispatch (ED) and limiting the SOC range of the ESS. Let the ESS join the Spinning Reserve. Through the PSS®E iterative ESS charging power required at moments when the frequency of contingency is too low in the ED. Let the ESS act as a N-1 contingency extra frequency reserve. This would prevent UFLS and still maintain the demand. The proposed method is applicable to different types of ESS. The method allows energy storages, originally designed for energy arbitrage, to participate in frequency support and spinning reserve.

Development of hybrid aluminum-air battery fuel-cell system

Industrial 4.0 accelerates the need to introduce clean energy to accommodate the increase in electricity demand globally without causing environmental issues. Metal-air battery is a new type of energy storage system in which the metal anode is consumed to generate electricity through the electrochemical reaction. Among various types of the metal anode, aluminum is a promising energy carrier. Aluminum-air battery shows advantages such as high capacity, abundance, low cost, and being environmentally friendly. Traditional aqueous aluminum-air battery experiences restriction from application due to its self-corrosion issues. In this study, instead of reducing or limiting the self-corrosion issues, a different approach is proposed so to make use of the self-corrosion issues of the aluminum-air battery. By incorporating an additional hydrogen-air subcell to the aluminum-air battery, this hybrid system turned the self-corrosion issue into a beneficial reaction by utilizing the hydrogen gas produced from the aluminum anode as the fuel to power the hydrogen-air fuel cell and improving the overall power performance. The electrical performance of each system is studied experimentally using potassium hydroxide electrolytes. The hybrid system shows a great improvement as compared to a single system. The maximum power is improved by more than 40%. This study shows that the hybrid design is feasible in enhancing the aluminum-air battery performance and yet, maintaining low cost and low weight in nature.

Agarose Gel-Templating Synthesis of a 3D Wrinkled Graphene Architecture for Enhanced Supercapacitor Performance.

The increasing use of rapidly fluctuating renewable energy sources, such as sunlight, has necessitated the use of supercapacitors, which are a type of energy storage system with high power. Chemically exfoliated graphene oxide (GO) is a representative starting material in the fabrication of supercapacitor electrodes based on reduced GO (rGO). However, the restacking of rGO sheets driven by π–π stacking interactions leads to a significant decrease in the electrochemically active surface area, leading to a loss of energy density. Here, to effectively inhibit restacking and construct a three-dimensional wrinkled structure of rGO (3DWG), we propose an agarose gel-templating method that uses agarose gel as a soft and removable template. The 3DWG, prepared via the sequential steps of gelation, freeze-drying, and calcination, exhibits a macroporous 3D structure and 5.5-fold higher specific capacitance than that of rGO restacked without the agarose template. Further, we demonstrate a “gel-stamping” method to fabricate thin-line patterned 3DWG, which involves the gelation of the GO–agarose gel within micrometer-sized channels of a customized polydimethylsiloxane (PDMS) mold. As an easy and low-cost manufacturing process, the proposed agarose gel templating method could provide a promising strategy for the 3D structuring of rGO.

Evaluating Options to Integrate Energy Storage Systems in Albania

The focus of the paper is to identify for the first time the most adequate energy storage systems (ESS) applicable in the central or bulk generation of the electricity sector in Albania. The application and integration of ESS is a smart way to overcome the problems of timely power supply volatility and minimizing energy losses, transmission congestion relief and upgrade deferral (top 10%), energy time shift (arbitrage), and many other services that reduce the cost of electricity and gain the security of energy supply. The presence of high-level rates of water discharges into the Hydropower Power Plants (HPP) and the problems of congestion in the transmission grid are the two main problems that require new methods for addressing and solving them. To select the right form and type of ESS that should be applied in our national energy system, E-select, a very flexible and internationally approved model is chosen. The results of this study are necessary for achieving a flexible, cheaper, and environmentally friendly energy system in Albania.

A Zero-Strain Insertion Cathode Material for Room-Temperature Fluoride-Ion Batteries.

A fluoride-ion battery (FIB) is a novel type of energy storage system that has a higher volumetric energy density and low cost. However, the high working temperature (>150 °C) and unsatisfactory cycling performance of cathode materials are not favorable for their practical application. Herein, fluoride ion-intercalated CoFe layered double hydroxide (LDH) (CoFe-F LDH) was prepared by a facile co-precipitation approach combined with ion-exchange. The CoFe-F LDH shows a reversible capacity of ∼50 mAh g-1 after 100 cycles at room temperature. Although there is still a big gap between FIBs and lithium-ion batteries, the CoFe-F LDH is superior to most cathode materials for FIBs. Another important advantage of CoFe-F LDH FIBs is that they can work at room temperature, which has been rarely achieved in previous reports. The superior performance stems from the unique topochemical transformation property and small volume change (∼0.82%) of LDH in electrochemical cycles. Such a tiny volume change makes LDH a zero-strain cathode material for FIBs. The 2D diffusion pathways and weak interaction between fluoride ions and host layers facilitate the de/intercalation of fluoride ions, accompanied by the chemical state changes of Co2+/Co3+ and Fe2+/Fe3+ couples. First-principles calculations also reveal a low F- diffusion barrier during the cyclic process. These findings expand the application field of LDH materials and propose a novel avenue for the designs of cathode materials toward room-temperature FIBs.

Renewable energy integration and microgrid energy trading using multi-agent deep reinforcement learning

To reduce global greenhouse gas emissions, the world must find intelligent solutions to maximise the utilisation of carbon-free renewable energy sources. In this paper, multi-agent reinforcement learning is used to control a microgrid in a mixed cooperative and competitive setting. The agents observe fluctuating energy demand, dynamic wholesale energy prices, and intermittent renewable energy sources to control a hybrid energy storage system to maximise the utilisation of the renewables to reduce the energy costs of the grid. In addition, an aggregator agent trades with external microgrids competing against one another and the aggregator to reduce their own energy bills. For this, the algorithm deep deterministic policy gradients (DDPG) and multi-agent DDPG (MADDPG) are used to compare the use of a single global controller versus multiple distributed agents, along with the single and multi-agent variants of distributional DDPG (D3PG) and twin delayed DDPG (TD3). The research found it is significantly more profitable for the primary microgrid to sell energy on its own terms rather than selling back to the utility grid, and is also beneficial for the external microgrids as they also reduce their own energy bills. The methods that produced the greatest profits were the multi-agent approaches where each agent has its own reward function based on the principle of marginal contribution from game theory. The multi-agent approaches were better able to evaluate their performance controlling individual components of the environment which allowed them to develop their own unique policies for the different types of energy storage system.

A comprehensive state‐of‐the‐art review of power conditioning systems for energy storage systems: Topology and control applications in power systems

Energy storage systems are pivotal for maximising the utilisation of renewable energy sources for smart grid and microgrid systems. Among the ongoing advancements in energy storage systems, the power conditioning systems for energy storage systems represent an area that can be significantly improved by using advanced power electronics converter designs and control techniques. Normally, the battery, flywheel, ultracapacitor and superconducting magnetic energy storage are the types of energy storage systems that typically require power conditioning systems for efficient bidirectional power flows. Compared to the previous review papers, this paper critically reviews the power conditioning system configurations and control techniques from the perspective of energy storage system applications in the power systems. First, the power conditioning systems are categorised into DC bus power conditioning systems and AC bus power conditioning systems based on the output voltage types at the connected point. Next, the topologies and control configurations of popular power electronics are comparatively analysed to highlight their advantages and power system applications. Moreover, the control configurations are discussed in terms of the popular applications of energy storage systems, that is, power backup smoothing, frequency regulation, voltage regulation and power quality applications. In addition, the latest developments in the energy storage system such as multi-functional energy storage system stacking, artificial intelligence for power conditioning system of energy storage systems and security of control of energy storage systems are critically analysed. Finally, the review is concluded by discussing industrial applications and future research trends for the power conditioning systems of energy storage systems.

Integrate multifunctional ionic sieve lithiated X zeolite-ionic liquid electrolyte for solid-state lithium metal batteries with ultralong lifespan

Solid-state lithium metal batteries with higher energy density and safety are regarded as the promising next-generation energy storage devices. Porous materials hybrid with ionic liquids are becoming an important solid electrolyte due to the high ionic conductivity and enhanced interfacial compatibility. However, their poor electrochemical stability and limited Li+ transport pathways remain challenged. Herein, an ionic-liquid-X zeolite hybrid is designed as the solid composite electrolyte to settle the above issues. The three-dimensional open framework of X zeolite acts as the “reservoir” of the ionic liquid providing a solid interconnected pathway to facilitate an effective lithium transmission. This transport is supported by both the TFSI− adsorption and EMIM+ substitution in zeolite structure, which benefits the compatibility at electrolyte/lithium anode interface. The obtained composite electrolyte (Li-X-30) exhibits a superior ionic conductivity of 3.3 × 10−4 S·cm−1 and a widened electrochemical window of 5.4 V. An ultralong lifespan of the assembled solid-state LiFePO4//metallic lithium battery is achieved with an outstanding capacity retention of 96% after 850 cycles. The designed electrolyte with ultra-long cycling stability may provide inspiration for the development of frontier solid electrolytes with potential applications in K, Na and other types of energy storage systems.

A Technology Review of Energy Storage Systems, Battery Charging Methods and Market Analysis of EV Based on Electric Drives

The transportation sector is by far the largest oil consumer making it a prime contributor to air pollution. EVs (Electric vehicles) will be beneficial to the environment and will help to alleviate the energy crisis due to their low dependence on oil and negligible emissions. Technology innovation in EVs is of significant interest to researchers, companies, and policy-makers in many countries. EVs integrate various kinds of distinct technologies where some of the important factors in considerations related to EVs are: a wide range of electrical drive configurations; advanced electronics that enable automotive innovations; meeting the challenges of automotive electronics; electrifying transportation in the future. This paper reviews the recent progress in EV technology, which consists of various motor drives applied in EV propulsion, classification of EVs such as BEV, PHEV, HEV, FCEV, and types of energy storage system with chargers, and software simulating devices. This paper also highlights the EV market with various challenges. The main findings of this research are: (1) Battery technology is the EV's bottleneck. Lithium-ion batteries for vehicles have high capacity and large serial-parallel numbers, which, coupled with problems such as safety, durability, uniformity, and cost, impose limitations on the wide application. (2) Incentives and encouragement for EV owners should be tailored to their specific needs in order to improve their socioeconomic standing. (3) Hyundai, MG Motors, Tesla, and Tata Motors appear to be the key players in India's critical subdomains of the EV market. (4) EV simulation software is necessary for vehicle design and development before the mass production of EVs. (5) PMSM has the potential to provide a high torque-to-current ratio, a high power-to-weight ratio, high efficiency, and robustness. Currently, the BLDC (Trapezoidal SPMSM) motors are the most preferred motors for electric vehicle applications due to their traction characteristics.

Optimal virtual synchronous generator control of battery/supercapacitor hybrid energy storage system for frequency response enhancement of photovoltaic/diesel microgrid

Stability of microgrids became an important issue especially with increasing the penetration of the inverter-based renewable energy sources (RESs) that characterized by their low inertia and naturally intermittent generated power. These two issues can be tackled by the utilization of the energy storage systems (ESSs), power electronics, and control techniques. Using a single type of ESS may fail to fulfill the system requirements, therefore a hybrid energy storage system (HESS) consists of supercapacitor and battery is employed. The proposed microgrid consists of photovoltaic (PV), diesel generator, HESS, and load. The HESS is controlled by virtual synchronous generator (VSG) technique, which imitates the performance of conventional synchronous generator. However, the frequency response of the microgrid strongly relies on the VSG's parameters. Design based on the small-signal model of VSG requires extensive analysis due to interaction among different generations and loads. Therefore, this work exploits particle swarm optimization (PSO) for designing optimal VSG using two objective functions. The first (OVSG_1) minimizes the integral time absolute error (ITAE) of the frequency, while the second (OVSG_2) considers the ITAE, frequency nadir, and rate of change of frequency (ROCOF) concurrently. Moreover, the proposed control system comprises droop control integrated with VSG, which enables the HESS to operate as a grid forming at outage of the diesel generation and to maintain the microgrid stability. For evaluating the different VSG controllers, several disturbances such as load variation, solar irradiance variation, and grid following/forming contingencies are carried out. In addition, the paper investigates the battery storage system performance with/without supercapacitor under different disturbances. The overall system is modeled and simulated using MATLAB™ platform.

Preface

The 9th International Conference on Advanced Manufacturing Technology and Materials Science (AMTMS 2021) was planned to be held on November 19-21, 2021 in Beijing, China. Considering the COVID-19 pandemic, the AMTMS 2021 conference was held virtually as agencies around the world are now issuing restrictions on travel, gatherings, and meetings to limit and slow the spread of this pandemic. The health and safety of our participants and members of our research community is of top priority to the Organizing Committee. Therefore, the AMTMS 2021 conference was held online through Zoom software.AMTMS 2021 is being organized by Beihang University to provide an opportunity to research scholars, delegates, and students to interact and share their experience and knowledge in Advanced Manufacturing Technology and Materials. We sincerely welcome all scientists, scholars, students, industrialists to attend and explore their knowledge in the field of Functional Materials and Applied Technologies. We strongly believe that AMTMS 2021 was a remarkable event which can bring together professors, researchers, and students in the field of functional materials and applied technologies making the conference a perfect platform to share experience, foster collaborations across industry and academia, and evaluate emerging technologies across the globe. More than 150 participants attended the online conference, they were from China, Canada, Malaysia and more.During the conference, the conference model was divided into three sessions, including oral presentations, keynote speeches, and online Q&A discussion. In the first part, some scholars, whose submissions were selected as the excellent papers, were given about 5-10 minutes to perform their oral presentations one by one. Then in the second and third part, keynote speakers were each allocated 30-45 minutes to hold their speeches. In the keynote speeches part, we invited four professors as our keynote speakers. Prof. Lu Li, National University of Singapore. Dr. Lu’s research interests include nanostructured materials, and functional thin films such as all-solid-state micro batteries and ferroelectric thin films. And then we had Prof. Sung-Hoon Ahn (CIRP Fellow), Seoul National University, South Korea. Dr. Ahn’s research interests include soft robotics, smart/composite materials, micro/nano fabrications, 3D/4D printing, smart factory, green manufacturing, renewable energy, smart grid, and appropriate technology. Prof. Lihui Lang, our third keynote speakers, from Beihang University, China. He mainly focuses on automotive, aircraft and aerospace fields. And then we invited Prof. Jiangfeng Ni, from Soochow University, China as our finale keynote speaker. At present Dr. Ni is leading a team working on various types of energy storage systems including rechargeable batteries, supercapacitors, with a focus on fundamental physics, chemistry, and materials in these devices. Their insightful speeches had triggered heated discussion in the third session of the conference. Every participant praised this conference for disseminating useful and insightful knowledge.The proceedings are a compilation of the accepted papers and represent an interesting outcome of the conference. Topics include but are not limited to the following areas: Materials Processing Technology and Materials Science, Manufacturing Technology and Systems and Other related topics. All the papers have been through rigorous review and process to meet the requirements of International publication standard.This year, we have all worked and lived with the daily threat of Covid-19, the need for social distancing and relative isolation has impacted upon the familiar and fundamental nature of conferences. Regardless, such interactions are the lifeblood of our respective communities, and so we made the decision to proceed with the Workshop, bring participants together from around the world through a digital platform. We would like to acknowledge all of those who supported AMTMS 2021. The help and contribution of each individual and institution was instrumental in the success of the conference. We would like to thank the organizing committee for its valuable inputs in shaping the conference program and reviewing the submitted papers.The Committee of AMTMS 2021List of Committee member are available in this pdf.

A multi-timescale operation model for hybrid energy storage system in electricity markets

The hybrid energy storage system (HESS) connecting different types of energy storage system (ESS) can be used to handle the several timescale variations of the components in power system. In this paper, a multi-timescale economic scheduling strategy for the HESSs to participate in the wholesale energy and reserve market considering the uncertainty of load and renewable generation. The economic multi-timescale HESS scheduling is a three-level model including day-ahead scheduling, intraday operation, and real-time operation. To better cover the hybrid requirements in the stochastic problem, the operation cycle limits model is introduced to avoid the frequent switching of energy-based ESS as well as the deviation cost of HESS’s capacity is used in the finer timescale to guide the future requirement. An improved algorithm that integrates the Progressive Hedging (PH) and Dual Decomposition (DD) algorithms are used to solve this problem. The proposed strategy can realize the efficient management of HESSs to reduce the energy management complexity and system operation costs with high computation efficiency, which indicates its promising application in the HESS economic scheduling.