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传统电力负荷预测法主要依据专家经验和现状年负荷值来预测未来年负荷,该方法具有一定的局限性。为合理预测园区负荷实际情况,采用了新的电负荷预测方法,即综合考虑典型用户性质、四季差异、作息时间等多种影响因素,通过研究园区全年负荷密度预测曲线的调整方法,并结合上海市典型用户实际负荷数据对模型进行了验证,为适应多应用场景的园区综合能源供应系统优化配置研究奠定基础。 相似文献
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微电网作为公用电网的有益补充,位于负荷末端,可以在电网末端起到提高用户供电可靠性,加强电网供电能力的作用,其规划设计必须紧密联系负荷情况确定。目前电网末端的负荷逐渐趋向于多元化,已不再仅仅为简单的电力负荷,逐渐向多元负荷的耦合性转化。探讨了在多元负荷情况下进行微电网负荷预测。阐述了现有负荷预测的方法,选择负荷密度法作为基础负荷预测方法,并以上海浦东为例进行了负荷特性调研,作为负荷密度法预测负荷的基础,然后针对微电网系统中较多出现的分布式电源及较大范围下可能出现的电动汽车的负荷进行了建模分析。其中,风电与光伏采取了数据拟合的方法求取了±95%概率下的出力;电动汽车利用蒙特卡洛模拟法分析了无序充放电及有序充放电情况下对微电网的负荷预测影响。 相似文献
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为了解决城市电力负荷的短期预测问题,本文提出了一种考虑日周期性的短期自回归预测方法。该方法利用城市集体负荷的日周期性,采用自回归的方法进行预测,并对预测的结果进行评估。本文的原始数据来自北方某城市18 435个用户,数据间隔为15 min一个测点,一天96个测点,共28天的历史数据。通过使用前27天的数据对第28天的数据进行了预测。通过将预测的功率曲线与实测的功率曲线进行比对,该方法对城市电力负荷短期预测取得了良好的效果。该研究可以为政府和电力调度部门提供建议,为城市以及园区级综合能源规划提供参考,并为精细化售电服务的套餐制定提供支持。 相似文献
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在新常态下为了降低生产成本,用户会参与需求响应进行错峰和避峰。传统负荷预测模型对用户负荷特性变化不敏感,对一些突变信息难以准确预测。针对此问题,考虑温度敏感用户参与需求响应,提出了夏季短期负荷预测方法。该方法采用小波变换和局部离群因子方法对负荷数据预处理,基于模糊C均值聚类和径向基函数网络相结合的方法识别预测日的负荷特性,采用线性回归模型对预测日的负荷特性相同的历史负荷数据进行负荷预测,根据降温负荷的基准值和温度变化值评估出降温负荷值,最后综合得出预测日的负荷。对3类温度敏感的纺织行业大用户进行算例分析,验证了所提方法的可行性和有效性。 相似文献
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传统的集中供暖系统热负荷预测取决于操作人员的经验,与系统实际热负荷相差过大,容易造成热用户侧温度过高或过低,影响热用户体验,不利于系统节能。采用机器自学习的方法,对大连某供热系统2019年至2021年的系统数据进行处理,基于多元线性回归、多项式回归、岭回归、Lasso回归、神经网络算法建立供热系统热负荷预测模型,并对比预测效果。结果显示:采用BP神经网络模型的供热系统热负荷预测结果比经验预测结果高8.7%,随着模型不断地自学习与自优化,预测结果的精度可进一步提高。 相似文献
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负荷预测在电网规划和运行中十分重要,大规模分布式能源接入电网参与能量交换,可使电网用户优化其用电模式,但造成区域电网月最大净负荷特性发生根本性改变,增加了月最大净负荷预测的不确定性。为此,结合BP神经网络算法与分位数回归模型,构建了区域电网月最大净负荷的非线性概率预测模型;并利用核密度估计算法计算得到了月最大净负荷概率预测分布曲线;最后,以上海某含分布式能源区域电网为例,验证了该方法的可行性与可靠性。结果表明,该方法可准确刻画月最大净负荷波动特性,为电网规划与负荷管理提供依据。 相似文献
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为分析负荷与温度的关系,充分利用有用的气象信息,以结构简单、解释能力强的回归预测方法为基础,提出基于温度近因效应的多元线性回归负荷预测模型。在构建回归模型时,引入虚拟变量描述负荷在年、周和日周期上的周期性变化规律,对周分类时兼顾考虑节假日负荷特殊性及与休息日负荷的相似性,对节假日及其邻近日做相应转换;在近因效应方面,采用滞后时温度和24h移动平均温度。研究结果表明,考虑温度近因效应可较大程度提升负荷预测精度。 相似文献
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以空调负荷的预测方法为研究对象,通过预测建筑物的空调负荷,及时有效地调控系统,达到降低建筑能耗的目的。基于最小二乘支持向量机(LS-SVM)提出预测方法,并采用粒子群算法(PSO)实现优化计算,围绕济南及成都地区不同类型建筑物的空调负荷进行预测,确定影响空调负荷的各个因素并在计算过程中不断调整以简化预测过程。采用Matlab语言进行编程计算和分析,通过不断调整输入因素及部分PSO参数以降低预测误差。基于支持向量机及粒子群算法的空调负荷预测模型性能较好,预测精度高。研究结果可为暖通空调系统的负荷预测提供参考,揭示空调负荷的变化特点以实现节能调控的目的。 相似文献
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综合能源系统中风电、光伏等可再生能源出力具有波动性和间歇性,精准的短期负荷预测有利于平抑可再生能源对系统运行的影响。系统中的多元负荷时间序列为典型的非平稳性信号,难以进行精准地预测。为了从数据层面提高综合能源系统短期负荷预测模型的精度,提出基于自适应局部迭代滤波(ALIF)的历史负荷数据分解方法,将历史负荷序列分解为具有不同频段模态函数的多个分量;针对预测模型训练中长时间序列处理困难及系统中多元负荷间耦合信息挖掘利用的问题,建立基于长短期记忆(LSTM)网络多任务学习的综合能源系统短期负荷预测模型。实验结果显示,与LSTM、ALIF-LSTM单任务学习、随机森林、LGBM方法相比,所提方法能够应对负荷波动剧烈的工况,预测精度较高,满足综合能源系统安全稳定运行控制的要求。 相似文献
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Structural loads of wind turbines are becoming critical because of the growing size of wind turbines in combination with the required dynamic output demands. Wind turbine tower and blades are therefore affected by structural loads. To mitigate the loads while maintaining other desired conditions such as the optimization of power generated or the regulation of rotor speed, advanced control schemes have been developed during the last decade. However, conflict and trade‐off between structural load reduction capacity of the controllers and other goals arise; when trying to reduce the structural loads, the power production or regulation performance may be also reduced. Suitable measures are needed when designing controllers to evaluate the control performance with respect to the conflicting control goals. Existing measures for structural loads only consider the loads without referring to the relationship between loads and other control performance aspects. In this contribution, the conflicts are clearly defined and expressed to evaluate the effectiveness of control methods by introducing novel measures. New measures considering structural loads, power production, and regulation to prove the control performance and to formulate criteria for controller design are proposed. The proposed measures allow graphical illustration and numerical criteria describing conflicting control goals and the relationship between goals. Two control approaches for wind turbines, PI and observer‐based state feedback, are defined and used to illustrate and to compare the newly introduced measures. The results are obtained by simulation using Fatigue, Aerodynamics, Structures, and Turbulence (FAST) tool, developed by the National Renewable Energy Laboratory (NREL), USA. 相似文献
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谢家安 《电网与水力发电进展》2012,28(8):24-28
针对体感温度与负荷之间的变化关系进行了深入研究,研究表明体感温度在不同范围内变化时将对地区负荷影响表现出截然不同特征。将负荷分为对体感温度敏感和不敏感2种类别,并提出2种负荷预测方法。2种负荷预测方法均以径向基神经网络为基础,并针对不同类型待预测负荷采取差异化样本选取和处理方法,有效提高了该负荷预测模型适用性和负荷预测精度。将该方法运用到某市总负荷预测中,预测结果表明该方法具有较高精度和较好实用性,是一种有效的短期负荷预测新方法。 相似文献
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Abdelaziz Salah Saidi Marwa Ben Slimene Mohamed Arbi Khlifi Mohammad Fazle Azeem Salah Al Ahmadi Azzedine Draou 《风能》2019,22(9):1243-1259
This study focuses on the stability of power system based on codimension‐two bifurcation theory. In this paper, we investigate the impact of load modeling on permissible wind power generation margins in distribution networks. The study considers codimension‐two bifurcations of equilibria and limit cycles in wind power systems depending on varying two parameters simultaneously. The principle parameter is the wind power generation, and the other parameter depends on the different types of loads. The types of loads are ZIP, exponential recovery, dynamic induction loads, and composite load models. To study the effects of the induction motor loads, the proportion of the static component in the motor load is changed and assessed with respect to their mechanical loads. Wind generation margin boundaries are traced, and saddle‐node, Hopf, and limit‐induced bifurcation branches are obtained, delimiting the stable and unstable operating regions in the parameter space. The analysis presented in this paper can pave the way for determining methods for improving and monitoring these margins with consideration to the system parameters and load composition. 相似文献
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In this paper, the proof of concept of a smart rotor is illustrated by aeroelastic simulations on a small‐scale rotor and comparison with wind tunnel experiments. The application of advanced feedback controllers using actively deformed flaps in the wind tunnel measurements is shown to alleviate dynamic loads leading to considerable fatigue load reduction. The numerical method for aeroelastically simulating such an experiment is described, together with the process of verifying the methods for accurate prediction of the load reduction potential of such concepts. The small‐scale rotor is simulated using the aeroelastic tool, load predictions are compared with the wind tunnel measurements, and similar control concepts are compared and evaluated in the numerical environment. Conclusions regarding evaluation of the performance of smart rotor concepts for wind turbines are drawn from this threefold research investigation (simulation, experiment and comparison). Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Site‐specific variability of load extremes of offshore wind turbines exposed to hurricane risk and breaking waves
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Much of the US offshore wind energy resource is located in shallow water off the Atlantic coast, which is exposed to both hurricanes and breaking waves. Current practice in offshore wind turbine (OWT) design is to realize a target structural reliability by amplifying loads using fixed load factors that do not vary with structural or site characteristics. Given that variability in both hurricane conditions and breaking waves is structure‐ and site‐specific, the structural reliability of OWTs may vary significantly from site to site if fixed load factors are used. To understand the implications of this situation, there is a need to compare the numerical values of fixed load factors with those calculated using methods that prescribe structure‐specific and site‐specific load amplification that reflects variability in long‐term conditions. In this paper, site‐specific load amplification is considered for four Atlantic coast locations and four water depths per location and then compared with fixed load factors commonly used in the design of OWTs. The study shows that decreasing water depth and increasing hurricane exposure tend to increase the required load amplification for consistent structural reliability. Another influential factor is the mean return period at which impact loads due to breaking waves begin to dominate the loading. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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为缓解区域内各省网的调峰压力,研究了多种耦合多电网调峰需求方案及统调比例设置方案;基于电网剩余负荷全时段平稳性和电网剩余负荷分峰谷时段平稳性,提出了两种不同的网际出力优化配置方法,并以华东简化系统为例进行了仿真分析。结果显示,按调峰压力现状设置权重及开放化设计统调比例最能协调各省网的调峰压力;两种网际出力配置方法均能有效缓解华东电网调峰压力。研究结果可为缓解区域各省网的调峰压力提供借鉴。 相似文献