Investigating Load Regulation Characteristics of a Wind-PV-Coal Storage Multi-Power Generation System

There is a growing need to explore the potential of coal-fired power plants(CFPPs)to enhance the utilization rate of wind power(wind)and photovoltaic power(PV)in the green energy field.This study developed a load regulation model for a multi-power generation system comprising wind,PV,and coal energy storage using realworld data.The power supply process was divided into eight fundamental load regulation scenarios,elucidating the influence of each scenario on load regulation.Within the framework of the multi-power generation system with the wind(50 MW)and PV(50 MW)alongside a CFPP(330 MW),a lithium-iron phosphate energy storage system(LIPBESS)was integrated to improve the system’s load regulation flexibility.The energy storage operation strategy was formulated based on the charging and discharging priority of the LIPBESS for each basic scenario and the charging and discharging load calculation method of LIPBESS auxiliary regulation.Through optimization using the particle swarm algorithm,the optimal capacity of LIPBESS was determined to be within the 5.24-4.88 MWh range.From an economic perspective,the LIPBESS operating with CFPP as the regulating power source was 49.1% lower in capacity compared to the renewable energy-based storage mode.

Equivalent Method of Integrated Power Generation System of Wind, Photovoltaic and Energy Storage in Power Flow Calculation and Transient Simulation

针对工程实际开展风光储联合发电系统在潮流计算和机电暂态仿真中的等值方法研究，旨在为大容量风光储联合发电系统的并网仿真分析奠定基础。将潮流计算的等值分为单元机组和集电系统2部分来研究。单元机组等值采用根据不同控制模式选取不同节点类型的方法，针对集电系统等值提出基于损耗不变原则的方法。等值模型和详细模型的算例结果表明，潮流计算等值方法具有较好的精度。在机电暂态仿真动态等值中，基于实际工程计算的最严重工况分析原则，提出运行在满出力点的单机“倍乘”等值模型，为工程计算中的风光储联合发电系统动态等值提供了一种解决方案。

Composition Modeling and Equivalence of an Integrated Power Generation System of Wind, Photovoltaic and Energy Storage Unit

利用间接组合建模的方法,在建立典型的双馈风机、光伏发电单元和储能单元的装置级机电暂态模型基础上,采用等值方法建立三者电站级的机电暂态模型,最终通过组合建模得到了风光储联合发电系统的机电暂态模型。在大型电力系统分析软件包的PSD-BPA暂态稳定程序中实现了风光储联合发电系统的仿真功能,通过典型算例和张北＂国家风光储输示范工程＂的仿真分析验证了模型的正确性,为风光储联合发电系统的并网研究提供了分析手段。

Reliability Assessment Considering the Coordination of Wind Power, Solar Energy and Energy Storage

风光储联合发电系统并网后必须采取策略与系统之间实现协调调度与运行才可在保证可靠性的前提下最大化利用可再生能源，但现有的可靠性评估中还缺少对大规模风光储联合发电系统协调运行的考虑。针对此问题，基于序贯蒙特卡罗仿真方法，建立了风电、光伏和储能系统的发电可靠性评估模型，并提出了新的协调调度策略。模型综合考虑了风速、太阳光辐照度、环境温度以及2种新能源发电技术的能量变换特性和储能系统的充放电约束等因素。这些模型被应用到IEEERTS79中，通过在Matlab中编制程序进行仿真计算，考察不同的协调运行策略、联合发电系统容量配置以及储能特性对于系统裕度的影响。评估结果可为联合发电系统并网规划与设计提供参考。

Application of Power Electronics Converters in Renewable Energy

Against the backdrop of global energy shortages and increasingly severe environmental pollution,renewable energy is gradually becoming a significant direction for future energy development.Power electronics converters,as the core technology for energy conversion and control,play a crucial role in enhancing the efficiency and stability of renewable energy systems.This paper explores the basic principles and functions of power electronics converters and their specific applications in photovoltaic power generation,wind power generation,and energy storage systems.Additionally,it analyzes the current innovations in high-efficiency energy conversion,multilevel conversion technology,and the application of new materials and devices.By studying these technologies,the aim is to promote the widespread application of power electronics converters in renewable energy systems and provide theoretical and technical support for achieving sustainable energy development.

Energy Storage Modeling of Inverter Air Conditioning for Output Optimizing of Wind Generation in the Electricity Market

In order to achieve the compatibility of the air conditioning(AC)loads with the current dispatch models,this pa-per utilizes demand response(DR)technology as energy storage resources to optimize the aggregator’s behaviors in the real-time market for less economic loss caused by the fluctuations of wind power.The inverter AC,as a typical demand response resource,is constructed as a power type battery model(PTBM)and a capacity type battery model(CTBM)according to the different control methods,which are expressed through a circuit model and mathematical model to describe the energy storage characteristics of ACs.Moreover,the comparisons between the PTBM and CTBM are given analytically by their response speed,power&energy capacity and the cost of control,which will be helpful to guide the associated operators to choose the appropriate models to take part in demand response.Considering that the wind generation fluctuates frequently and greatly,the PTBM is chosen to take part of the demand response for output optimizing of the wind generation.The simulation results demonstrate that PTBMs can work in the way of conventional batteries(CBs)to optimize wind generation in the real-time market.

Operation Strategies for Coordinating Battery Energy Storage with Wind Power Generation and Their Effects on System Reliability

The variability of wind power generation requires the allocation of a flexible energy reserve which is capable of compensating for possible imbalances between the load and generation. To reduce the variability of wind power generation and loss of load in generation deficit, we propose operation strategies for coordinating battery energy storage with wind power generation. The effects of the operation strategies on system reliability are evaluated by the developed computation model that represents the main aspects and operation limitations of the batteries. The performance evaluation of the power system is based on the composite reliability indices of loss of load probability(LOLP) and expected energy not supplied(EENS), which is calculated through sequential Monte Carlo simulation. Tests are performed by the developed model with a tutorial system consisting of five busbars and the IEEE RTS system. The results show that the use of large-scale batteries is an alternative to physically guarantee the wind power plants and to act as an operation reserve to reduce the risk of loss of load.

Reliability evaluation of tidal and wind power generation system with battery energy storage

This paper presents a method for reliability evaluation of a hybrid generation system of wind and tidal powers with battery energy storage.Such a system may widely exist in coastal areas and islands in the future.A chronological multiple state probability model of tidal power generation system(TPGS)considering both forced outage rate(FOR)of the TPGS and random nature of tidal current speed is developed.In the evaluation of FORs of TPGS and WPGS(wind power generation system),the delivered power related failure rates of power electronic converters for TPGS and WPGS are considered.A chronological power output model of battery energy storage system(BESS)is derived.A hybrid system of tidal and wind generation powers with a BESS is used to demonstrate the effectiveness of the presented method.In case studies,the effects of various parameters on the system reliability are investigated.

Frequency-constrained Co-planning of Generation and Energy Storage with High-penetration Renewable Energy

Large-scale renewable energy integration decreases the system inertia and restricts frequency regulation. To maintain the frequency stability, allocating adequate frequency-support sources poses a critical challenge to planners. In this context, we propose a frequency-constrained coordination planning model of thermal units, wind farms, and battery energy storage systems (BESSs) to provide satisfactory frequency supports. Firstly, a modified multi-machine system frequency response (MSFR) model that accounts for the dynamic responses from both synchronous generators and grid-connected inverters is constructed with preset power-headroom. Secondly, the rate-of-change-of-frequency (ROCOF) and frequency response power are deduced to construct frequency constraints. A data-driven piecewise linearization (DDPWL) method based on hyperplane fitting and data classification is applied to linearize the highly nonlinear frequency response power. Thirdly, frequency constraints are inserted into our planning model, while the unit commitment based on the coordinated operation of the thermal-hydro-wind-BESS hybrid system is implemented. At last, the proposed model is applied to the IEEE RTS-79 test system. The results demonstrate the effectiveness of our co-planning model to keep the frequency stability.

多能互补发电系统故障识别与测距方法

随着大量新能源的接入,使得多端柔性直流系统(modular multilevel converter based multi-terminal direct current, MMC-MTDC)故障特征愈加复杂,快速准确的故障识别与测距是亟需解决的关键难题之一。为此,提出了一种风-光-储-蓄互补发电站经柔性直流输电外送系统故障识别与测距方法。首先,搭建风-光-储-蓄互补发电站经柔直外送系统,在此基础上,提出了一种Teager能量算子能量熵的新方法,利用测量点正负极Teager能量算子能量熵的比值构建故障选极及区段识别判据。接着,针对已识别的故障线路,提出变分模态分解(variational mode decomposition, VMD)与Teager能量算子(teager energy operator, TEO)相结合的故障测距方法。最后,利用PSCAD/EMTDC进行仿真,结果表明所提识别方法可以准确判断故障所在线路,所提测距方法能在故障发生2 ms时间窗内实现故障测距,误差率不超过2.55%,并具有较高的耐过渡电阻能力。

光储充电站多目标自适应能量调度策略

针对光储充电站运营中利润过低、充电桩降功率供电易发和光伏弃光严重的问题,提出了一种基于参考点的非支配排序自适应遗传算法的能量调度策略,目的是提高充电站的运营效益.首先,以最大化充电站利润、充电桩满足率和光伏消纳度为目标建立多目标优化模型;其次,为避免传统NSGA-Ⅲ算法早熟问题,构建了一种自适应的二进制变异算子,以提高其种群多样性;最后,针对多目标优化求解所得的Pareto最优解集难以筛选问题,采用模糊层次分析法从中选出唯一最优解.实验结果表明,该策略在满足100%光伏消纳度的同时,相比其他多目标优化策略提高了0.45%~9.55%的充电站利润和0.42%~5.64%的充电桩满足率.另外,超体积指标表明所改进的算法有更好的收敛性和分布性.

小型风光储联合发电系统的设计

针对新疆维吾尔自治区农牧地区自然资源优势及日益增长的用电需求,设计了一种可移动式小型风光储联合发电系统,用于满足当地居民及牧民对便携式发电设备的需求。对该发电系统的总体设计方案、硬件及软件的设计分别进行了介绍,并通过实验验证了该发电系统能较稳定的跟踪太阳。该发电系统整体上实现了太阳能、风能的独立及互补发电,提高了资源利用率,且其结构简单、价格低廉,作为初级阶段的研究成果可供相关设计参考。

某机修工程光储直柔系统方案探讨

在分析光储直柔系统原理基础上,以某新建机修工程智慧低碳建筑为例,构建光储直柔微网系统和光储充微网系统,并对两种方案进行设计对比分析探讨,以实现新能源的更好利用。

离网型风光氢储系统容量配置与控制优化

为进一步提高离网型风光制氢系统的经济性以及运行稳定性,提出离网型风光氢储系统容量配置与控制优化方法。首先,结合风力机、光伏组件、碱性电解槽和锂电池的运行特性建立容量配置模型;以系统收益最大为优化目标,采用灰狼优化算法(GWO)进行求解。其次,提出基于区间最值的灰狼算法优化长短期记忆网络(GWO-LSTM)组合预测模型,并以此为基础开展系统运行控制策略研究。最后,针对张家口崇礼风电制氢示范工程项目数据进行算例分析,结果表明采用灰狼优化算法对风光氢储系统进行容量配置能增加系统收益,同时验证了提出的系统控制策略能保证系统平稳运行。

内蒙古自治区巴彦淖尔市工业园区风光储一体化项目容量配比研究

为探究风光储一体化项目各部分的最佳容量配比,以内蒙古自治区巴彦淖尔市某工业园区为例,基于园区新增负荷和风能、太阳能资源,计算得出风电和光伏发电的全年逐时及逐月典型日的输出功率曲线,然后在满足园区新增负荷用电需求的条件下,得出风电和光伏发电容量配比方案。鉴于风电和光伏发电的间歇性和波动性,引入储能以平滑输出功率曲线,实现了风光联合发电的发电量曲线与园区新增负荷用电量曲线的变化趋势相匹配。为提高园区的绿电替代率并降低风光联合发电弃电量,通过分析不同容量配比对风光联合发电消纳和绿电替代率的影响,得到最佳容量配比方案。可为内蒙古自治区工业园区风光储一体化项目提供一种有效的容量配比计算方法,有助于优化项目运行效率并推动绿色能源的广泛应用。

区域电网风光最优配比及储能优化配置研究

合理优化风光储容量配比是省级电网实现大规模区域电网新能源高效利用的基础,为优化风光储容量配比以及进一步降低弃电率,首先,基于某区域电网相关评价指标,对某区域电网风光出力特性进行分析,并使用风光出力场景生成方法生成某区域电网目标年的风光出力场景。其次,提出了面向提高新能源消纳的风光配比优化方法,包括新能源消纳模型和风光规划装机配比优化模型。随后,提出了面向提高新能源消纳的储能优化配置方法。最后,通过风光配比优化方法对某区域电网目标年弃电情况进行评估,并计算得到了某区域电网目标年的风光规划装机最优配比,通过算例验证所提方法的有效性。

基于PPO算法的光储式充电站储能运行策略

电动汽车的随机充电与光伏出力的波动特性给光储式充电站的经济高效运行提出了新的要求。为此,提出了一种基于深度强化学习近端策略优化(Proximal Policy Optimization,PPO)算法的光储式充电站储能运行策略。首先,对光储式充电站系统结构进行了分析,并建立了以综合运行成本最小为目标的储能运行模型。其次,将该模型转化为马尔科夫决策过程,并采用深度强化学习PPO算法进行训练求解。最后,在一个光储式充电站中进行算例仿真,验证所提策略的有效性。

Market-oriented Optimal Dispatching Strategy for a Wind Farm with a Multiple Stage Hybrid Energy Storage System

With the increased promotion of integrated energy power systems(IEPS),renewable energy and energy storage systems(ESS)play a more important role.However,the fluctuation and intermittent nature of wind not only results in substantial reliability and stability defects,but it also weakens the competitiveness of wind generation in the electric power market.Meanwhile,the way to further enhance the system reliability effectively improving market profits of wind farms is one of the most important aspects of Wind-ESS joint operational design.In this paper,a market-oriented optimized dispatching strategy for a wind farm with a multiple stage hybrid ESS is proposed.The first stage ESS is designed to improve the profits of wind generation through day-ahead market operations,the real-time marketbased second stage ESS is focused on day-ahead forecasting error elimination and wind power fluctuation smoothing,while the backup stage ESS is associated with them to provide the ancillary service.An interval forecasting method is adopted to help to ensure reliable forecast results of day-ahead wind power,electricity prices and loads.With this hybrid ESS design,supply reliability and market profits are simultaneously achieved for wind farms.

Optimal Sizing of Solar/Wind Hybrid Off-Grid Microgrids Using an Enhanced Genetic Algorithm

This paper presents a method for optimal sizing of an off-grid hybrid microgrid (MG) system in order to achieve a certain load demand. The hybrid MG is made of a solar photovoltaic (PV) system, wind turbine (TW) and energy storage system (ESS). The reliability of the MG system is modeled based on the loss of power supply probability (SPSP). For optimization, an enhanced Genetic Algorithm (GA) is used to minimize the total cost of the system over a 20-year period, while satisfying some reliability and operation constraints. A case study addressing optimal sizing of an off-grid hybrid microgrid in Nigeria is discussed. The result is compared with results obtained from the Brute Force and standard GA methods.

新型风光抽水蓄能系统研究

将云南已经建设的小型梯级水电站与光电、风电结合,形成新型抽水蓄能系统,将不稳定电力转化成稳定电力,能提升枯期供电能力,是适合云南省或类似地区的储能技术.