Characteristics Of Energy Storage System Research Articles

The potential of residential load flexibility: An approach for assessing operational flexibility

This study presents a novel methodology for evaluating the flexibility of residential electricity consumers under diverse operational conditions introducing innovative flexibility indicators. The increasing demand for energy flexibility from the demand side is crucial for ensuring the power grid’s economic stability and resilience. Buildings offer a range of potential flexibility sources that can be effectively leveraged for this purpose. Accordingly, this paper formulates energy flow management in a Smart House using a Mixed-Integer Linear Programming (MILP) framework, incorporating the scheduling of shiftable appliances and an Energy Storage System (ESS). By defining different consumption strategies, the feasible region for Energy-Time Profiles (ETPs) is explored through the establishment of the corresponding optimization problems. A series of case studies are presented to evaluate the impact of operational constraints on the feasible region. Finally, by meticulously analyzing the characteristics of ETPs extracted from these case studies, the proposed flexibility indicators are introduced, quantifying the Smart House’s energy flexibility potential. Furthermore, a sensitivity analysis is conducted to scrutinize the influence of key parameters on the new flexibility indicator, encompassing ESS characteristics. The findings substantiate the efficacy of the proposed indicators in providing comprehensive insights into the potential energy flexibility under a range of operational conditions.

Applications of energy storage systems in power grids with and without renewable energy integration — A comprehensive review

Energy storage system (ESS) is recognized as a fundamental technology for the power system to store electrical energy in several states and convert back the stored energy into electricity when required. Some excellent characteristics such as availability, versatility, flexible performance, fleet response time, modularity etc., make ESS more attractive for power system applications. The ESS has signification contributions and applications to operate the power system optimally in power grids with and without integrating renewable energy (RE) systems. This paper presents a comprehensive review of ESS technologies and their applications in power grids. Five different types of ESS, namely mechanical, chemical, electrical, electro-chemical and thermal, are elaborately explored with their key characteristics and applications. A summary of comparative analysis to find the appropriate ESS for power system applications and an analysis of the practical implementation of different ESS worldwide have been presented briefly, reflecting the suitability of ESS for power system applications. The comparative analysis further demonstrates the nature of various ESS, including their advantages and limitations in specific applications. The major challenges from these analyses are identified to be the capacity of ESS, RE integration, high maintenance and implementation cost of ESS, ESS degradation, waste management and associated environmental pollution. Moreover, the review finds out that there are still numerous challenges in terms of technology and economy that need to be addressed to make the practical applications of ESS viable for power industries. The reviews also identify recent key researches that can effectively address those issues and explore the future directions researchers can undertake to improve various characteristics of ESS. Finally, the transition pathway to promote ESS for power systems applications with and without integration of RE systems is discussed to demonstrate the possibility and potentiality of large-scale ESS deployment for a sustainable climate-friendly future.

태양광 연계 에너지저장장치 내부 환경 특성 분석

This paper analyzed internal environmental impact of energy storage device facilities connected to the photovoltaic power generation system. The use of energy storage system is increasing for demanding in new renewable energy (photovoltaic power, wind power, etc.) and adjusting frequency regulation(FR) in system operation.BRSince fires are concentrated in energy storage systems for connection with renewable energy, it is necessary to find the cause of the fire through analysis of the on-site installation environment and operation. This paper analyzes the internal environmental characteristics of energy storage systems connected to photovoltaic power generation and proposes a safety plan.

Wind-Thermal-Energy Storage System Optimization: Evidence from Simulations of the Economical Consumption of Wind Energy

To realize the economical consumption of wind energy (WE), an optimal dispatch strategy for wind-thermal-energy storage systems (WTESSs) is proposed. The scheduling model is divided into two stages. In the first stage, the strategy aims to shave peaks and fill valleys in the load curve using a time-of-use (TOU) electricity price and to reduce the variance of the net load and use the energy time-shift characteristics of energy storage systems (ESSs) to optimize their charging and discharging power. In the second stage, the strategy minimizes the cost of WTESSs, obtaining the output power of the thermal power units (TPUs) in each period. Considering the actual need for carbon reduction, a method for calculating the TPUs’ life loss cost under different variable load amplitudes is introduced, and a thermal power peaking cost model considering the ladder-type carbon trading model is constructed to calculate the cost accurately. In addition, to account for the fact that connecting all wind power outputs to the grid will significantly increase the grid peak regulation pressure and operational risk, a mathematical model for WE utilization is established to find the optimal power value for wind power grid connection in each period, which enables economical and practical WE scheduling. According to the simulation results, the overall peak-shaving cost of the system can be reduced by up to 23.95%, and the thermal power deep peak regulation cost can be reduced by up to 90.06%.

An Operation Strategy of ESS for Enhancing the Frequency Stability of the Inverter-Based Jeju Grid

As environmental pollution deteriorates, the acceleration of decarbonization worldwide is underway. Several countries, including Korea, are incorporating new and renewable energy into existing systems, and various methods of decarbonization are being researched. With changes in the control environment, the expansion of the system linkage of new and renewable energy can cause system instability problems. This paper introduces an operation plan that uses the fast response characteristics of energy storage system(s) (ESS) to improve stability and review system stability as a result of the expansion of new and renewable energy on Jeju Island. Frequency stability was ensured through an analysis of frequency response characteristics in the event of a system accident, and an efficient ESS operation plan was simulated by changing the ESS parameters. Through this simulation, stable ESS operation and hunting in the frequency recovery process were minimized through cooperation between the existing and new ESS via a wide dead-band range and speed adjustment rate correction, and the lowest frequency was improved.

Local energy markets for thermal-electric energy systems considering energy carrier dependency and energy storage systems

In this work, a local multi-modal energy market is introduced to couple district heating and electric systems. In the course of the ongoing decarbonization of energy systems, electric systems have to integrate more and more volatile renewable energies, whereas in thermal systems, the demand for sustainable heat generation is continuously increasing. Market-based coordination of local thermal-electric energy systems can help to alleviate these challenges. In this work, an adequate representation of conversion assets, e.g., heat pumps, is achieved by introducing novel coupling orders in the market. These enable an explicit coupling of heat and electricity, and thus cross-energy load-shifts. In addition, a new type of storage orders is introduced to offer flexibility options by energy storage systems in the local energy system. The benefits of the market scheme are demonstrated for a day ahead cycle of an exemplary local energy system in Germany. Inter alia, the results lead to the conclusion that coupling orders are able to alleviate price and volume risks of market participants with conversion assets. Moreover, storage orders can provide operational benefits to the local energy system, while respecting the physical characteristics of energy storage systems. For the specified day ahead cycle, the peak load to the transmission grid can be decreased by up to 18.34%, and, thus improving the self-sufficiency of the local energy system.

Frequency control strategy for coordinated energy storage system and flexible load in isolated power system

The isolated power system has a simple structure with small inertia and no support from the large-scale power system, so the frequency stability problem is more prominent. A frequency control method based on coordinated control of flexible loads (FL) and energy storage systems (ESS) is proposed in this paper. The ESS adopts the droop control considering the state of charge (SOC) to quickly respond to the system frequency deviation and provide fast frequency support. Based on the load power–voltage sensitivity, the FL participates in frequency control by adjusting the load voltage and thus the load demand. Based on the two frequency regulation resources, the active–reactive cooperative control strategy is proposed to adopt the fast response characteristics of ESS to cooperate with the synchronous unit to prioritize frequency regulation and enable the FL reactive control strategy when the system disturbance is larger than the primary frequency regulation capacity of the synchronous unit. The effectiveness of the proposed control strategy for isolated power systems is verified by building a modified IEEE33 node islanding system simulation in the real-time digital simulator (RTDS).

Low-frequency oscillation suppression strategy considering dynamic power characteristics of energy storage system

Aiming at the problem of low-frequency oscillation in the weak power grid, a low-frequency oscillation suppression strategy considering the dynamic power characteristics of the energy storage system (ESS) is proposed in this paper. Firstly, the principle of low-frequency oscillation in the power system is analyzed by using a single machine infinite bus system. Secondly, considering the dynamic characteristics of the ESS output active power, a controller for the ESS to suppress low-frequency oscillation is designed, which can provide positive damping for frequency oscillation of the power grid. Finally, the simulation analysis and experimental results of an actual weak grid are carried out to verify the effectiveness and feasibility of the proposed method. The results show that the suppression effect of the low-frequency oscillations is related to the ESS location in the weak power grid.

Evaluating the Electrochemical Properties of Supercapacitors using the Three-Electrode System.

The three-electrode system is a basic and general analytical platform for investigating the electrochemical performance and characteristics of energy storage systems at the material level. Supercapacitors are one of the most important emergent energy storage systems developed in the past decade. Here, the electrochemical performance of a supercapacitor was evaluated using a three-electrode system with a potentiostat device. The three-electrode system consisted of a working electrode (WE), reference electrode (RE), and counter electrode (CE). The WE is the electrode where the potential is controlled and the current is measured, and it is the target of research. The RE acts as a reference for measuring and controlling the potential of the system, and the CE is used to complete the closed circuit to enable electrochemical measurements. This system provides accurate analytical results for evaluating electrochemical parameters such as the specific capacitance, stability, and impedance through cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). Several experimental design protocols are proposed by controlling the parameter values of the sequence when using a three-electrode system with a potentiostat device to evaluate the electrochemical performance of supercapacitors. Through these protocols, the researcher can set up a three-electrode system to obtain reasonable electrochemical results for assessing the performance of supercapacitors.

Design Framework for Privacy-Aware Demand-Side Management With Realistic Energy Storage Model

Demand-side management (DSM) is a process by which the user demand patterns are modified to meet certain desired objectives. Traditionally, DSM was utility-driven, but with an increase in the integration of renewable sources and privacy-conscious consumers, it also becomes a “consumer-driven” process. Promising theoretical studies have shown that privacy can be achieved by shaping the user demand using an energy storage system (ESS). In this paper, we present a framework for utility-driven DSM while considering the user privacy and the ESS operational cost due to its energy losses and capacity degradation. We propose an ESS model using a circuit-based and data-driven approach that can be used to capture the ESS characteristics in control strategy designs. We measure privacy leakage using the Bayesian risk of a hypothesis testing adversary and present a novel recursive algorithm to compute the optimal privacy control strategy. Further, we design an energy-flow control strategy that achieves the Pareto-optimal trade-off between privacy leakage, deviation of demand from a DSM target profile, and the ESS cost. With numerical experiments using real household data and an emulated lithium-ion battery, we show that the desired level of privacy and demand shaping performance can be achieved while reducing the ESS degradation.

Research on Hybrid Energy Storage Configuration in Grid Wind Power Scheduling Tracking Under Statistics and Frequency Decomposition

AbstractThe low accuracy of wind power scheduling influences the grid dispatch adversely, increasing the demand for spinning to reserve capacity and obstructing the grid frequency regulation. Considering the throughput characteristics of energy storage system, which can be used to compensate for wind farm power scheduling deviations, and smooth the grid power fluctuations, the hybrid energy storage (HES) is employed to enhance the dispatch ability of wind power generation. As one of the key techniques, desirable energy storage capacity configuration (ESCC) and control methods would accelerate the application of energy storage in the field of new resource. Combined with statistics and frequency decomposition of scheduling power deviation, HES capacity configuration and online dynamic power allocation method are proposed. First, by analysis of grid assessment indexes of wind power, scheduled wind power data are produced by improved adaptive error factor correction particle swarm optimization back-propagation neural network (AEFC-PSO-BPNN) prediction followed by wavelet packet smooth (WPS). After comparing with actual power, scheduling deviation statistics and frequency decomposition are applied in capacity and power configuration of energy storage, as well as dynamic power distribution control. With wind/storage simulation platform, then, feasibility of energy storage embedded in grid wind power scheduling deviation, regulation is verified under several combined methods, and the proposed ESCC methods are tested in application case by grid wind power indexes of root-mean-square error rate (RMSE), average volatility (AV), maximum throughout power and current (MTP, MTC), actual supercapacitor (SC), battery consumption capacity, and the number of crossings of state of charge (SOC) of HES. Finally, analyses and comparison of energy storage capacity requirements are carried out on different scheduling deviation control methods so as to explore the significant factors influencing capacity allocation. Applying these methods can improve the scheduling accuracy of grid wind power, reduce power fluctuations at the power common connected (PCC) point, and minimize the impact of accessed wind power to the grid as much as possible.

Optimization Strategy for Hybrid Energy Storage Power Distribution Based on Fuzzy Control

In order to solve the problem of intermittence and fluctuation of output power of photovoltaic (PV) power generation system, a fuzzy control based optimization method for power distribution of hybrid energy storage system is proposed. Compared with the traditional hybrid energy storage system (HESS) control method, this method can use the ensemble empirical mode decomposition (EEMD) and fuzzy control algorithm to realize the reasonable distribution of charge and discharge power of hybrid energy storage system. EEMD technology is used to decompose the unbalanced power signal in the system, and realize the power distribution of super capacitor and battery according to the characteristics of energy storage system. The fuzzy controller is used to optimize the distribution power of the hybrid energy storage system, to control the charge and discharge of the energy storage device reasonably. Under the action of the fuzzy controller, the hybrid energy storage system can choose the appropriate operation mode to maintain the stability of DC bus voltage according to the energy storage state of charge (SOC) and power fluctuation. Finally, the simulation example verifies the rationality and superiority of the proposed method.

Probabilistic Modeling of Energy Storage to Quantify Market Constrained Reliability Value to Active Distribution Systems

Integration of an energy storage system (ESS) into a distribution network not only affects the supply reliability of the customer, but also has distinct reliability implications and consequences to the utility. The reliability value associated with an ESS highly depends on the ownership, market, and regulatory structures. This paper presents a probabilistic framework to evaluate the reliability value of ESS to the distribution system considering aforementioned factors. In this regard, a new probabilistic reliability model of ESS is developed and integrated into a sequential Monte Carlo based simulation framework. The developed ESS model consists of the Markov-based component model and the mixed integer linear programming based formulation of operating strategies that incorporate different scenarios of ownership, market structures, and the ESS characteristics. The reliability/financial risk performance of the distribution system operator (DSO) with ESS under quality regulations are quantified. Furthermore, the developed ESS model is utilized to explore the prospect of investor-owned ESS providing supply recovery and distribution grid capacity services to the DSO. Case studies are conducted on a test distribution network to show the effectiveness of the proposed model. Finally, the paper presents discussions on important considerations for efficient utilization of ESS in active distribution systems.

Economic Dispatch of Multiple Energy Storage Systems Under Different Characteristics

This paper presents economic dispatch of the grid-connected microgrid that contains multiple energy storage systems as its only controllable distributed energy resources. Daily control schedules of distributed energy resources are achieved by solving the economic dispatch problem. The main objective of economic dispatch is maximizing the profit from the power trade with the grid. The economic dispatch problem presented in this paper considers the different characteristics of energy storage systems. Each energy storage system has its unique characteristics such as the charge/discharge efficiency and capacity fade rate. The result of the multi-objective problem shows that the energy storage system with the highest efficiency and the lowest capacity fade rate is controlled more frequently than the others. The Pareto optimal set of the resulting control schedules is presented.

Development and Analysis of Switched Capacitor Four Quadrant DC-DC Converter for Hybrid Electric Vehicle

Background/Objectives: The main objective of this research is to develop a bi-directional four quadrant DC-DC converter for an energy efficient electric vehicle. Methods/Analysis: The model of electric vehicle is designed using MATLAB software. The results confirm that the proposed DC-DC converter structure is highly reliable, lighter in weight, smaller in volume, with good efficiency, less electromagnetic interference and lower current or voltage ripple. Findings: The issues on global warming and fossil fuels depletion have created opportunities to Electric Vehicle (EV). The main characteristics of Energy storage system in vehicles include energy density, power density, lifetime, cost and maintenance. Most of the electric and hybrid electric configurations use two energy storage devices, one with high energy storage capacity, called the Main Energy System (MES) and the other with high power capacity called the Auxiliary Energy Storage System (AESS). Other challenge in electric vehicle is to maintain the state of charge within the allowable limits and sharing of energy between the storage devices. For proper sharing of energy between the storage devices, DC-DC converter plays a crucial role. Novelty/Improvement: A novel Switched Capacitor DC-DC power converter and their controllers are investigated.

Study on Charging and Discharging Characteristics of Energy Storage System in Wind Storage Power Plant under the Condition of Black Start

Grid black start refers to the process that power with self-start ability starts and leads the restart of the entire grid in "full blackout" status. In this paper, it selects the wind power plant containing energy storage device as the black-start power to study the charging/discharging problems of VRB in the self- start process in wind field.

수용가용 전력저장시스템의 경제성분석에 관한 연구

Recently, BESS is considered as one of essential countermeasure for demand side management. However, an economic evaluation is critical issue for the introduction of power system because the cost of BESS is very high in present stage. Therefor, this paper presents economic evaluation method for customer use case by considering peak shaving function based on the real time price. From the case study on the model power system and educational customer, it is confirmed that the proposed method is a practical tool for the economic analysis of BESS. and analytical approach for the reliability assessment in radially operated distribution systems. The approach can estimate the expected reliability performance of distribution systems by a direct assessment of the configuration of the systems using the reliability indexes such as NDP (Non-Delivery Power) and NDE (Non-Delivery Energy). The indexes can only consider the number and configuration of the load, but can not consider the characteristics of the load which is the one of the most important factor in the investment cost for the distribution systems. Therefore, this paper presents the new performance indexes for the investment of the distribution facilities considering both the expected interruption cost for the load section and the operation characteristics of Energy Storage System. The results from a case study show that the proposed methods can be a practical tool for the reliability management in distribution systems including Energy Storage System.

RTDS를 이용한 신재생에너지 기반 마이크로그리드 시뮬레이션 해석

Due to enhanced demands on quality, security and reliability of the electric power energy system, a microgrid has become a subject of special interest. In this paper, output characteristics of energy storage system (ESS) with an electric double layer capacitor (EDLC) and battery energy storage system (BESS) of a renewable energy based microgrid were analyzed under grid-connected and islanded operation modes. The microgrid which consists of photovoltaic and wind power turbine generators, diesel generator, ESS with an EDLC, BESS and loads was modeled using real time digital simulator. The results present the effective control patterns of the microgrid system.

A study of the melting heat transfer characteristics of energy storage system utilizing the pcm.

This study is concerned with anti-precipitation experiments to extend the life cycle of PCM by adding Celite, and also to determine melting heat transfer characteristics experiment of PCM in a PCM cylindrical heat exchanger with six fins. Experimental results are compared with theory to investigate the appropriateness of the unsteadystate two-dimensional heat conduction equation, and the effects of fluid inlet temperature and flowrate on the total melting time of PCM are investigated. Experimental results show that the optimum PCM mixture is 70.5 weight percent of Glauber''s salt and 0.25 weight percent of Celite as thickener, and they are within 5 % agreement with the enthalpy model. It is confirmed that the heat transmission enthalpy model is appropriate for analysis of the melting heat transfer characteristics of PCM. The total melting Fourier number has the following relationships with respect to the Biot number and Stefan number. (NFo)m=0.0551(NBI)-0.343(NSTE)-0.733