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1.
提出一种用神经网络设计提前一天的短期负荷预测系统的方法.在对神经网络进行训练前,先通过一种简单的方法对数据进行了预处理,以使设计的系统具有处理由于突发事件等因素引起负荷突然变化的能力.用山东省电网2003年的负荷数据进行试验,试验结果表明方法的适用性. 相似文献
2.
提出了电力系统短期负荷预报基于模糊集的神经网络方法 .该方法计及了天气和日期特征量 ,具有训练时间短预测精度高的特点 .采用两种学习算法 ,依据模糊集概念用某地区电网实际数据建立样本集后 ,对ANN进行了训练 ,通过分析比较得出了优化模型 .计算事例表明用该方法是可行和有效的 相似文献
3.
给出了改进的BP网络和RBF网络的构造过程和训练方法.在改进的BP网络中不仅加入了动量项和变步长法,而且在模型中合理地考虑了影响负荷变化的主要气象因素,使其能够适应天气的变化.在RBF网络中,为了克服传统K均值聚类法局部寻优的缺陷,采用了正交最小二乘法选取RBF中心.利用改进的BP网络和RBF网络进行了短期电力负荷预测,并对训练的收敛速度和预测精度进行了分析.比较两种模型,RBF网络比BP网络更具有实用性和可开发性. 相似文献
4.
In order to resolve the coordination and optimization of the power network planning effectively, on the basis of introducing
the concept of power intelligence center (PIC), the key factor power flow, line investment and load that impact generation
sector, transmission sector and dispatching center in PIC were analyzed and a multi-objective coordination optimal model for
new power intelligence center (NPIC) was established. To ensure the reliability and coordination of power grid and reduce
investment cost, two aspects were optimized. The evolutionary algorithm was introduced to solve optimal power flow problem
and the fitness function was improved to ensure the minimum cost of power generation. The gray particle swarm optimization
(GPSO) algorithm was used to forecast load accurately, which can ensure the network with high reliability. On this basis,
the multi-objective coordination optimal model which was more practical and in line with the need of the electricity market
was proposed, then the coordination model was effectively solved through the improved particle swarm optimization algorithm,
and the corresponding algorithm was obtained. The optimization of IEEE30 node system shows that the evolutionary algorithm
can effectively solve the problem of optimal power flow. The average load forecasting of GPSO is 26.97 MW, which has an error
of 0.34 MW compared with the actual load. The algorithm has higher forecasting accuracy. The multi-objective coordination
optimal model for NPIC can effectively process the coordination and optimization problem of power network.
Foundation item: Project (70671039) supported by the National Natural Science Foundation of China 相似文献
5.
进行负荷预测时,由于中长期负荷历史数据较少而制约因素较多,因此预测难度较大。在分析了灰色预测和神经网络预测优缺点的基础上,提出了多因素灰色神经网络组合预测模型(GANO)。该模型首先采用灰色GM(1,n)模型处理多因素的影响,进而利用BP神经网络训练电力历史负荷数据,最后利用统计方差的倒数建立较为理想的优化组合预测模型。该优化模型结合了各模型优点且综合考虑了电力负荷的多种制约因素。经算例验证,优于单一历史负荷预测模型,有效地提高了中长期负荷预测精度。 相似文献
6.
改进遗传神经网络及其在负荷预测中的应用 总被引:1,自引:0,他引:1
针对遗传算法早熟的缺陷,提出了改进的交叉,变异策略,采用移民算子等方法改善遗传算法的性能,并把此方法应用到神经网络的训练中,对电力系统短期负荷进行预测取得了较为理想的效果。 相似文献
7.
In order to improve the accuracy of short-term load forecasting of power system, a multi-scale information fusion convolutional neural network(MS-ConvNet)model based on deep learning technology was proposed. A full convolution network structure and causal logic constraints were introduced to enhance the expression of time series features; a multi-scale convolution was utilized to extract the relationship among time domain data of different lengths for obtaining more abundant series features; a residual network structure was designed to increase the network depth, which increased the acceptance domain of outputneurons and enhanced the prediction accuracy. The results show that the accuracy and stability of MS-ConvNet model is better than those of multi-layer perceptron machine, long-short term memory network and gated recurrent unit network, indicating that the as-proposed model has a good application prospect in power load forecasting. 相似文献
8.
为了能够及时准确地进行电力系统短期负荷的预测,采用RBF神经网络和自适应模糊控制相结合的预测方法,首先通过RBF神经网络进行负荷预测,然后利用自适应模糊控制对预测结果进行在线修正,实验结果证明了该方法的正确性与可行性。 相似文献
9.
A new grey forecasting model based on BP neural network and Markov chain was proposed. In order to combine the grey forecasting model with neural network, an important theorem that the grey differential equation is equivalent to the time response model, was proved by analyzing the features of grey forecasting model(GM(1,1)). Based on this, the differential equation parameters were included in the network when the BP neural network was constructed, and the neural network was trained by extracting samples from grey system’s known data. When BP network was converged, the whitened grey differential equation parameters were extracted and then the grey neural network forecasting model (GNNM(1,1)) was built. In order to reduce stochastic phenomenon in GNNM(1,1), the state transition probability between two states was defined and the Markov transition matrix was established by building the residual sequences between grey forecasting and actual value. Thus, the new grey forecasting model(MNNGM(1,1)) was proposed by combining Markov chain with GNNM(1,1). Based on the above discussion, three different approaches were put forward for forecasting China electricity demands. By comparing GM(1, 1) and GNNM(1,1) with the proposed model, the results indicate that the absolute mean error of MNNGM(1,1) is about 0.4 times of GNNM(1,1) and 0.2 times of GM(1,1), and the mean square error of MNNGM(1,1) is about 0.25 times of GNNM(1,1) and 0.1 times of GM(1,1). 相似文献
10.
预测城市用水量的人工神经网络模型研究 总被引:6,自引:1,他引:6
为了提高多层前馈神经网络权的学习效率,引入变尺度方法来训练神经网络的权值,并根据训练误差自适应调整学习系数和动量因子.将该方法应用于城市用水量预测中,建立了非线性人工神经网络预测模型.该模型考虑了城市工业用水重复利用率、用水人口、经济发展等众多因素对用水量需求的影响,具备系统决策功能.杭州市预测实例表明,建立的模型及其相应计算方法具有较高的预测精度和准确度. 相似文献
11.
利用改进的主成分分析(MPCA)方法对径向基函数神经网络输入空间进行重构,在降低输入空间维数的同时克服了传统主成分分析法的缺点,缩小了网络的结构,达到了提高网络泛化能力的目的。通过某省实例验证了该方法的有效性。 相似文献
12.
The fuzzy neural network is applied to the short-term load forecasting. The fuzzy rules and fuzzy membership functions of the network are obtained through fuzzy neural network learming. Three inference algorithms, i.e. themultiplicative inference, the maximum inference and the minimum inference, are used for comparison. The learningalgorithms corresponding to the inference methods are derived from back-propagation algorithm. To validate the fuzzyneural network model, the network is used to Predict short-term load by compaing the network output against the realload data from a local power system supplying electricity to a large steel manufacturer. The experimental results aresatisfactory. 相似文献
13.
对基于神经网络的有效停车泊位预测方法进行研究,通过调查及采集商业中心区停车场停放车辆的实时数量信息,建立相应的神经网络模型,并运用MATLAB仿真分析软件实现实时有效停车泊位预测,最后对误差结果进行分析和解释。 相似文献
14.
改进的人工神经网络水文预报模型及应用 总被引:14,自引:0,他引:14
在人工神经网络水文模型的研究中,往往加入前期径流以提高模型的预报精度.针对由此带来的问题,通过耦合总径流线性响应模型,建立一种基于人工神经网络的实时预报模型.通过引入总径流线性响应模型的模拟径流作为模型输入,模型的模拟模式能够提供较长的预见期,同时加入误差校正模型的实时预报模式也能够取得较高的模型精度.采用3个不同流域的流量资料对模型进行率定与校核.结果表明,模型能够取得较高的预报精度,显示了良好的适用性. 相似文献
15.
赵钊林 《福建建筑高等专科学校学报》2011,(1):58-60
根据对电网负荷预测业务的分析,采用探索型数据分析方法对电力企业数据仓库中的数据进行训练建模,构建出电网负荷预测模型。模型应用情况表明:应用该模型后电力企业负荷预测较传统预测方法准确率明显提高,电力企业预测技术水平相应提高,同时,应用该模型还有助于电力企业有计划地进行用电管理,确保电力企业决策分析可行性。 相似文献
16.
基于免疫粒子群优化的一种动态递归神经网络辨识与控制非线性系统 总被引:1,自引:1,他引:1
提出了一种采用免疫粒子群优化算法对动态递归神经网络进行训练的方法,实现了对Elman网络的结构、权重、结构单元的初始输入和自反馈增益因子等参数的同时进化训练。进而针对非线性系统分别提出了相应的辨识与控制算法,并设计出了相应的辨识器和控制器。最后以超声马达为对象进行了仿真,结果表明:基于所提出的算法而设计的辨识器和控制器在辨识和控制过程中不仅都能取得很高的收敛精度和速度,而且对于随机扰动有较强的鲁棒性,从而为非线性系统的辨识和控制提供了一条新的途径。 相似文献
17.
随着风电的大规模接入电网,对风电功率未来出力的把握显得尤为重要,而风电功率预测技术则是掌握出力特性的有力工具。基于实测历史数据,研究系统不同输入量对预测结果误差的影响,选取最佳输入量值;并在此基础上,构建基于RBF(径向基)神经网络的风电功率预测模型,对风电功率进行有效预测;预测结果表明,基于径向基神经网络的预测方法预测精度较高,可以为电网提供更加准确的风电预测出力信息,有助于为调度制定更加合理有效的计划。 相似文献
18.
基于RBF神经网络的交通流预测 总被引:5,自引:0,他引:5
针对交通模型是一个非线性、不确定的复杂动力学系统,难以用精确模型来表达的问题,采用RBF神经网络建立交通流预测模型,具有较强的局部泛化能力,收敛速度快,克服了BP神经网络收敛速度慢、易陷入局部极小的缺点.实例仿真研究表明,该方法预测效果较好. 相似文献
19.
分析了基于对角递归神经网络观测器控制系统的动态性能和鲁棒性能.基于对角递归神经网络观测器将实际测得的电压和电流经过坐标变换后估测出电流和角速度,用估测值与实际值的差值调节神经网络观测器连接权值,直到预测误差达到设定值.该控制器具有不依赖被控对象的精确数学模型、对外界环境变化具有学习性、自适应性及鲁棒性等特点.仿真表明,该方法具有较好的转子位置和速度跟踪特性,系统具有较强的抗负载扰动性能和控制性能,能够满足精度高、反应快、鲁棒性好的要求. 相似文献
20.
运用反向传播(back propagation, BP)的改进算法弹性梯度下降算法,选择崇阳溪上游流域1997—2014年的14场降雨径流过程,以流域内洋庄、吴边、大安、坑口、岭阳、岚谷6个雨量站的实测降雨量和武夷山水文站的前期流量资料为输入,武夷山水文站相应流量为输出,建立弹性梯度下降算法的BP神经网络降雨径流预报模型,采用7场降雨径流过程对模型进行检验。结果表明,与传统的反向传播算法相比,该模型所需的参数较少,运算速度显著提高,模型的预报精度满足要求,可以为防汛部门预测洪水提供依据。 相似文献