Energy Management for a Residential Microgrid Using Wavelet Transform and Fuzzy Control Including a Vehicle-to-Grid System

This paper presents the design and implementation of an energy management system （EMS） with wavelet transform and fuzzy control for a residential micro-grid. The hybrid system in this paper consists of a wind turbine generator, photovoltaic （PV） panels, an electric vehicle （EV）, and a super capacitor （SC）, which is able to connect or disconnect to the main grid. The control strategy is responsible for compensating the difference between the generated power by the wind and solar generators and the demanded power by the loads. Wavelet transform decomposes the power difference into a smoothed component and a fast fluctuated component. The command approach used for fuzzy logic rules considers the state of charging （SOC） of EV, renewable production, and the load demand as parameters. Furthermore, the command rules are developed in order to ensure a reliable grid when taking into account the EV battery protection to decide the output power of the EV. The model of the hybrid system is developed in detail under Matlab/Simulink software environment.

Optimal configuration strategy of energy storage system in high photovoltaic penetration micro-grid based on voltage sensitivity analysis

Energy storage is an effective measure to deal with internal power fluctuation of micro-grid and ensure stable operation, especially in the micro-grid with high photovoltaic(PV) penetration. Its capacity configuration is related to the steady, safety and economy of micro-grid.In order to improve the absorptive capacity of micro-grid on maximizing the use of distributed PV power in micro-grid, and improve the power quality, an optimal energy storage configuration strategy is proposed, which takes many factors into account, such as the topology of micro-grid, the change of irradiance, the load fluctuation and the cable. The strategy can optimize the energy storage allocation model to minimize the storage power capacity and optimize the node configuration.The key electrical nodes are identified by using the sensitivity coefficient of the voltage, and then the model is optimized to simplify calculation. Finally, an example of the European low-voltage micro-grid and a micro-grid system in the laboratory is used to verify the effectiveness of the proposed method.The results show that the proposed method can optimize the allocation of capacity and the node of the energy storage system.

Economic Feasibility of Micro-Grid Energy Storage and the Impact of Emerging Technologies on Its Viability

Currently, energy storage devices show great promise when used in micro-grid applications, and further advancements in this technology will lead to economically-viable and environmentally-friendly solutions in regards to residential energy consumption. Creating a 21st-century energy infrastructure will be fundamental to society in the coming decades and ensuring cost-effective means of doing so will lessen the burden on the average consumer. While current research has focused primarily on fundamental battery research, the economic viability for the average American consumer has been neglected in many cases. In this work, current and future methods of home energy storage are analyzed via a thorough literature review and the most promising current and near-future methods are explored. These methods include current Lithium-Ion Battery (LIB) technology, reused LIB from Electric Vehicles (EVs), Lithium Nickel manganese cobalt oxides (NMC) cathode composition and the utilization of silicon as an anode material. After the potential of these technologies is explored, an analysis of their economic viability for the average consumer is presented. The literature review demonstrates that the current state of LIB is very close to economically feasible;reused LIBs are less viable than new LIBs, and future LIB compositions show great promise in viability. This shows that within the next decade, micro-grids will be a reasonable alternative to utility energy harnessing techniques, and a major step towards green energy consumption will be realized. Hybrid energy storage systems, on the other hand, are shown to be economically infeasible, in the near future, due to their high cost per kWh. However, when analyzing the energy storage capabilities of these systems, it is shown that they may be vital in updated energy infrastructure and provide a cost saving.

Control System Development and Test for the Operation of a Micro-Grid System—PART I

This paper presents design, analysis and simulation performance of an active power controller for stable and reliable operation of a micro-grid system. Power balance between generation and consumer is a critical issue for stable and reliable operation of the micro-grid systems. This issue becomes more critical when a micro-grid system contains stochastic nature distributed generations such as wind and solar because their output power changes non-uniformly. In order to achieve accurate and fast power balance in such a micro-grid system, power in the system has to be regulated continuously. Such an objective can be achieved using droop based alternating current control technique. Because the droop characteristic employed into the developed controller initiates determining the power deviation in the system which is continuously regulated by controlling the current flow into dump power resistors. The designed controller is simulated for the operation of a micro-grid system in stand-alone mode under various operating conditions. The simulated results show the ability of the developed controller for stable and reliable operation of the micro-grid that contains renewable sources. The experimental development of the micro-grid system and the testing of the developed active power controller are presented in PART II of this paper.

Electronic Controlled Energy Storage Devices and Applications in Future Smart Grid

This paper discusses the future power system consisting of distributed generations connected to local loads in the form of micro-grid systems.The benefits of having energy storage systems and the role of power electronics in micro-grid systems are presented.This paper also examines how micro-grids have a key role to play in the development of the smart grid.

Micro-Grid Planning with Aggregator’s Role in the Renewable Inclusive Prosumer Market

The paper proposes a model for a micro-grid architecture incorporating the role of aggregators and renewable sources on the prosumer side, working together to optimize configurations and operations. The final model takes the form of a mixed-integer linear programming model. This model is solved using the CPLEX solver via GAMS by having a consistent data set.

Trends and Overview Regarding the Involvement of Micro-Grids in Modern Power Systems

Customer satisfaction and participation in utility supply packages is the first and foremost factor in the success of any supplying agency whether wholesale or retail dealer. The paper presents the concept of major prospects of non- autonomous micro-grids installed in a certain locality. The article shows the basic background that is required for the installment of micro grid in a particular area and discusses the primary factors or pre-requisites that are required for the existence and operation of micro-grids. It elaborate the major profitable applications and benefits that developing and developed states get by using micro-grids in an area where utility grid is already functioning .It also explains the basic improvement in the quality of supply from micro grid after its installment. It also throws light on afterwards impact on society with this system, such impacts include reliability, tariff rates, economics etc. The article discusses micro-grids as the future of modern power systems. This paper shows significance of modernization by latest topologies in power systems and its effect that will come afterwards.

Control System Development and Test for the Operation of a Micro-Grid System—PART II

This paper presents experimental development and performance testing of an active power controller for stable and reliable operation of a micro-grid system. In order to achieve accurate and fast power balance in a micro-grid system that contains renewable energy sources, power in the system has to be regulated continuously. Such an objective can be achieved using droop based alternating current control technique. Because the droop characteristic employed into the developed controller initiates to determine the power deviation in the system which is continuously regulated by controlling the current flow into dump power resistors. The designed controller is tested and validated using a micro-grid prototype in the laboratory environment for stand-alone mode of operation under various operating conditions. The key development in the micro-grid prototype is the development of a wind turbine simulator. A dSPACE ds1104 DSP board is used to implement and interface the designed controller with the micro-grid system. The experimental investigation of the developed controller presents the significant capability to achieve continuous power balance in the micro-grid system, while it maintains stable and reliable operation of the system. Finally, the power quality of the isolated micro-grid system is presented and discussed under the operation of the developed controller.

Managing of Smart Micro-Grid Connected Scheme Using Group Search Optimization

This article introduces a group search optimization (GSO) based tuning model for modelling and managing Smart Micro-Grids connected system. In existing systems, typically tuned PID controllers are engaged to point out the load frequency control (LFC) problems through different tuning techniques. Though, inappropriately tuned PID controller may reveal pitiable dynamical reply and also incorrect option of integral gain may even undermine the complete system. This research is used to explain about an optimized energy management system through Group Search Optimization (GSO) for building incorporation in smart micro-grids (MGs) with zero grid-impact. The essential for this technique is to develop the MG effectiveness, when the complete PI controller requires to be tuned. Consequently, we proposed that the proposed GSO based algorithm with appropriate explanation or member representation, derivation of fitness function, producer process, scrounger process, and ranger process. An entire and adaptable design of MATLAB/SIMULINK also proposed. The related solutions and practical test verifications are given. This paper verified that the proposed method was effective in Micro-Grid (MG) applications. The comparison results demonstrate the advantage of the proposed technique and confirm its potential to solve the problem.

Autonomous Multi-Factor Energy Flows Controller (AmEFC): Enhancing Renewable Energy Management with Intelligent Control Systems Integration

The transition to sustainable energy systems is one of the defining challenges of our time, necessitating innovations in how we generate, distribute, and manage electrical power. Micro-grids, as localized energy hubs, have emerged as a promising solution to integrate renewable energy sources, ensure energy security, and improve system resilience. The Autonomous multi-factor Energy Flow Controller (AmEFC) introduced in this paper addresses this need by offering a scalable, adaptable, and resilient framework for energy management within an on-grid micro-grid context. The urgency for such a system is predicated on the increasing volatility and unpredictability in energy landscapes, including fluctuating renewable outputs and changing load demands. To tackle these challenges, the AmEFC prototype incorporates a novel hierarchical control structure that leverages Renewable Energy Sources (RES), such as photovoltaic systems, wind turbines, and hydro pumps, alongside a sophisticated Battery Management System (BMS). Its prime objective is to maintain an uninterrupted power supply to critical loads, efficiently balance energy surplus through hydraulic storage, and ensure robust interaction with the main grid. A comprehensive Simulink model is developed to validate the functionality of the AmEFC, simulating real-world conditions and dynamic interactions among the components. The model assesses the system’s reliability in consistently powering critical loads and its efficacy in managing surplus energy. The inclusion of advanced predictive algorithms enables the AmEFC to anticipate energy production and consumption trends, integrating weather forecasting and inter-controller communication to optimize energy flow within and across micro-grids. This study’s significance lies in its potential to facilitate the seamless incorporation of RES into existing power systems, thus propelling the energy sector towards a more sustainable, autonomous, and resilient future. The results underscore the potential of such a system to revolutionize energy management practices and highlight the importance of smart controller systems in the era of smart grids.

计及碳交易与需求响应的微能源网双层优化模型

该文在微能源网的基础架构上,以全年总成本最低为目标函数,结合碳交易与需求响应构建微能源网双层优化配置模型。结合区域环境数据与年度典型日案例分析,优化模型得到最优规划配置以及在该配置下的各设备最优日运行出力调度情况,相比基础模型提高了可再生能源装机容量并获得了更高的碳排放权收益,通过需求响应调整用户侧灵活可控负荷,在保证可再生能源的消纳能力的前提下,有效节省了总成本。算例结果表明,该模型能够使微能源网在保证系统经济性的同时促进实现减碳目标,对MEG的前期规划设计有重要意义。

考虑源-荷不确定性的微能源网区间规划方法

微能源网存在复杂的能量流动,其源-储优化配置成为其建设初期的首要挑战。此外,微能源网包含的不确定性,特别是风能、太阳能和多能负荷功率的随机波动性难以描述和克服。为解决上述问题,文中将可再生能源和负荷需求的不确定性描述为区间,以年折算投资成本最小为目标,耦合线性化交流潮流模型,计及冷/热/电功率平衡约束、节点电压静态安全约束、线路容量约束、热管道传输功率约束,并基于区间线性规划理论将相应的不确定性约束转化为确定性约束,构建了考虑源-荷不确定性的微能源网区间最优规划模型。通过算例分析验证了模型的可行性和优越性,规划方案可以适应不同的不确定场景,能够保证系统的稳定运行。

考虑电-氢-热多能互补的微网多目标优化配置

氢储能具有储能容量大、储存时间长、清洁无污染、可实现多种能源网络互联互补和协同优化等诸多优点,有望成为推动分布式能源发展和提升终端能源利用效率的重要支撑技术。为了提高独立型微网供电可靠性及可再生能源利用率,文中分析了典型电、氢、热装置的运行特性,提出考虑电-氢-热多能互补的独立微网多目标优化配置模型,并基于模拟退火的粒子群(simulated annealing particle swarm optimization,SAPSO)算法对目标问题进行求解,获得不同配置方案下的技术经济指标。最后,通过东北某地独立微网优化配置算例,基于MATLAB平台验证了所提多能互补配置方案较传统电储能配置方案负荷失电率降低了3.18%,可再生能源利用率提高了8.37%。所提配置方案可有效促进可再生能源消纳,保证独立微网的供电可靠性。

基于谈判博弈的微电网群多主体共享储能容量优化配置策略

大力发展新能源是构建新型电力系统、推动能源转型的必然选择。文章提出了基于谈判博弈的微电网群多主体共享储能容量优化配置方法。考虑微电网群运营商(MGCO)与共享储能运营商(SESO)之间的协同交互机制,建立基于共享储能的微电网群容量优化框架;考虑微电网之间的能量共享以及共享储能容量租赁,构建考虑能量共享的微电网群容量优化配置模型;计及共享储能动态租赁,构建SESO储能容量优化配置模型;在此基础上,构建基于谈判博弈的MGCO和SESO储能容量配置模型,并提出基于ADMM的分布式求解方法。基于MATLAB进行算例分析,结果表明,所提储能优化配置方法能够在降低MGCO成本的同时提高SESO的收益,达到了双赢的效果。

海岛多能源微网故障免疫及谐波滤除的隔离变压器方案

为解决某海岛微网系统面临的多能源发电单元易受外部故障解列及3倍次谐波自由传递导致系统电能质量低下等问题,提出一种综合电站出口增设隔离变压器的一次系统改进方案。基于该海岛微网的多能源结构、海岛环境、高可靠性要求等特殊应用场景,阐述隔离变压器方案,验证同步机组励磁系统缺陷及新能源发电单元导致的谐波来源;配合应用虚拟同步发电机的光伏蓄电池支路,通过系统故障电压支撑能力、三相/零序不平衡度及谐波畸变率量化隔离变压器方案,对发电单元隔离保护及系统电能质量的提升效果有促进作用。经电磁暂态平台PSCAD验证,新方案使发电单元免疫外部故障零序冲击,综合电站出口处电压支撑能力提高了52.44%,畸变度降低了78.04%,基本完全滤除占比14.33%的励磁缺陷谐波电流,具备传统滤波器方案不具备的故障免疫及谐振过电压抑制作用,为海岛多能互补电网工程建设提供参考性方案。

考虑双重SOC的混合储能系统功率协调控制

为了降低直流微网系统中负载变化或者多源出力变化引起的功率波动,提出一种同时考虑蓄电池和超级电容荷电状态(state of charge,SOC)的混合储能协调控制策略。首先,分析直流微网系统协调控制原理,在此基础上,通过低通滤波器对所需平抑功率进行分频,低频功率由蓄电池承担,高频功率及系统开关的高频纹波由超级电容承担,根据频率响应确定了滤波器的时间常数调整原则;然后,将超级电容和蓄电池各自的SOC实时状态作为反馈观测量,根据两者的SOC状态并结合实际功率需求,将系统划分成11个工作模式,分析了不同工作模式下的功率需求,依据不同工作模式下的功率需求进行功率调整,进而实现功率二次分配;最后,将所提策略在4种典型情况下进行仿真验证,实验结果验证了该策略的有效性。

考虑新能源出力不确定性的风-光-柴-储系统调度策略

文章以风-光-柴-储系统为研究对象,为了研究新能源出力不确定性对该系统的影响,提出了一种新能源出力复合预测模型。为提高风-光-柴-储系统运行的经济性、环保性和安全性,提出了考虑新能源出力不确定性的风-光-柴-储系统调度模型,并采用了带有Monte Carlo模拟的遗传算法对模型进行求解。文章采用了负荷缺失率(load loss rate,LLR)和置信概率对系统的安全性进行评价,并分析了其对系统调度结果的影响。仿真结果表明,文中所提出的考虑新能源出力不确定性的风-光-柴-储系统调度模型,可以降低新能源出力不确定性对系统的影响,且该方法可以有效地平衡系统的经济性和安全性。

光储充建一体站微电网研究综述

为解决电动汽车及新能源大规模接入带来的电力系统运行稳定和新能源高效利用的问题,光储充一体化模式应运而生,其各单元间源荷储协同交互机理及优化调控策略也成为智能电网亟待解决的关键问题。“光储充放+智能建筑”的光储充建一体站微电网模式因其源荷储一体化、供需互补、灵活调度等特征,成为中国节能减碳、能源转型的发展重点。考虑到其微电网运行模式所要面对的分布式能源强不确定性、孤岛并网运行状态下交互机理不明等挑战,对光储充建一体站微电网各单元模块、关键技术、运行状态等方面进行综述,并对光储充建的研究现状进行总结,探讨其未来的发展趋势和需要面对的挑战。研究成果对挖掘经济激励下各类需求响应资源的调控潜力,保障电网供电可靠性,具有重要理论和实际参考意义。

基于栅条式微涡絮凝的隧道废水处理技术数值模拟

为探究微涡混凝技术在隧道废水处理工艺上的可行性,通过数值模拟手段对不同特征的栅条式微涡发生器所产生的混凝流场特性进行了研究,并采用最优组合形式对浊度为1300 NTU模拟隧道废水进行了水力絮凝验证实验.结果表明:栅条的粗细主要影响流场内流体湍动能及湍耗散的在初始混凝阶段的消耗程度,边长为5 mm的方形栅条更容易维持整个流场内混凝过程中所需的动能;栅条布置间距会改变栅条对流体的阻滞作用,布置间距为11mm时,流体能在反应中后段提供更高的湍动能及湍耗散用于絮凝反应;栅条的长度主要影响流场在轴向方向的能量演变情况,400、600、800 mm的栅条会延长流体在流场内的能量分配距离,使反应器中后段的絮体也能够有足够用于聚集的能量.采用最优组合形式的栅条对浊度为1300 NTU模拟隧道废水进行了水力絮凝验证实验,废水最终出水浊度可稳定在50 NTU以下.

考虑源-荷不确定性的微能源网日前鲁棒优化调度

微能源网集成园区/社区的分布式能量系统、多元荷载及控制装置,能够实现多能源联产联供功能,有利于提升各类能源网络运行灵活性和经济性。为有效应对微能源网内部负荷和新能源出力的不确定性,首先建立多面体不确定集刻画负荷和光伏出力波动情况,构建描述微能源网网络拓扑和能流耦合关系的能源集线器(energy hub,EH)耦合矩阵。然后,以最小化系统运行成本为目标建立微能源网在并网和孤岛运行模式下的两阶段鲁棒优化经济调度模型,并运用线性决策规则(linear decision rule,LDR)和对偶理论制定模型求解策略。最后,基于IEEE 33节点配电网改进设计的微能源网进行算例验证分析。结果表明,LDR能够在一定精度范围内通过线性仿射函数有效近似刻画决策变量和不确定变量间的关系,降低两阶段鲁棒优化经济调度模型的求解难度。