Multi-Time Scale Optimal Scheduling of a Photovoltaic Energy Storage Building System Based on Model Predictive Control

Building emission reduction is an important way to achieve China’s carbon peaking and carbon neutrality goals.Aiming at the problem of low carbon economic operation of a photovoltaic energy storage building system,a multi-time scale optimal scheduling strategy based on model predictive control(MPC)is proposed under the consideration of load optimization.First,load optimization is achieved by controlling the charging time of electric vehicles as well as adjusting the air conditioning operation temperature,and the photovoltaic energy storage building system model is constructed to propose a day-ahead scheduling strategy with the lowest daily operation cost.Second,considering inter-day to intra-day source-load prediction error,an intraday rolling optimal scheduling strategy based on MPC is proposed that dynamically corrects the day-ahead dispatch results to stabilize system power fluctuations and promote photovoltaic consumption.Finally,taking an office building on a summer work day as an example,the effectiveness of the proposed scheduling strategy is verified.The results of the example show that the strategy reduces the total operating cost of the photovoltaic energy storage building system by 17.11%,improves the carbon emission reduction by 7.99%,and the photovoltaic consumption rate reaches 98.57%,improving the system’s low-carbon and economic performance.

Low-carbon generation expansion planning considering uncertainty of renewable energy at multi-time scales

With the development of carbon electricity,achieving a low-carbon economy has become a prevailing and inevitable trend.Improving low-carbon expansion generation planning is critical for carbon emission mitigation and a lowcarbon economy.In this paper,a two-layer low-carbon expansion generation planning approach considering the uncertainty of renewable energy at multiple time scales is proposed.First,renewable energy sequences considering the uncertainty in multiple time scales are generated based on the Copula function and the probability distribution of renewable energy.Second,a two-layer generation planning model considering carbon trading and carbon capture technology is established.Specifically,the upper layer model optimizes the investment decision considering the uncertainty at a monthly scale,and the lower layer one optimizes the scheduling considering the peak shaving at an hourly scale and the flexibility at a 15-minute scale.Finally,the results of different influence factors on low-carbon generation expansion planning are compared in a provincial power grid,which demonstrate the effectiveness of the proposed model.

Bio-Inspired Optimal Dispatching of Wind Power Consumption Considering Multi-Time Scale Demand Response and High-Energy Load Participation

Bio-inspired computer modelling brings solutions fromthe living phenomena or biological systems to engineering domains.To overcome the obstruction problem of large-scale wind power consumption in Northwest China,this paper constructs a bio-inspired computer model.It is an optimal wind power consumption dispatching model of multi-time scale demand response that takes into account the involved high-energy load.First,the principle of wind power obstruction with the involvement of a high-energy load is examined in this work.In this step,highenergy load model with different regulation characteristics is established.Then,considering the multi-time scale characteristics of high-energy load and other demand-side resources response speed,a multi-time scale model of coordination optimization is built.An improved bio-inspired model incorporating particle swarm optimization is applied to minimize system operation and wind curtailment costs,as well as to find the most optimal energy configurationwithin the system.Lastly,we take an example of regional power grid in Gansu Province for simulation analysis.Results demonstrate that the suggested scheduling strategy can significantly enhance the wind power consumption level and minimize the system’s operational cost.

Multi-time scale analysis of precipitation variation in Guyuan, China:1957-2005

Morlet wavelet transformation is used in this paper to analyze the multi time scale characteristics of pre cipitation data series from 1957 to 2005 in Guyuan region.The results showed that(1) the annual precipitation evo lution process had obvious multi time scale variation characteristics of 15 25 years,7 12 years and 3 6 years,and different time scales had different oscillation energy densities;(2) the periods at smaller time scales changed more frequently,which often nested in a biggish quasi periodic oscillations,so the concrete time domain should be ana lyzed if necessary;(3) the precipitation had three main periods(22 year,9 year and 4 year) and the 22 year period was especially outstanding,and the analysis of this main period reveals that the precipitation would be in a relative high water period until about 2012.

Research on multi-time scale doubly-fed wind turbine test system based on FPGA+CPU heterogeneous calculation

As the proportion of renewable energy increases, the interaction between renewable energy devices and the grid continues to enhance. Therefore, the renewable energy dynamic test in a power system has become more and more important. Traditional dynamic simulation systems and digital-analog hybrid simulation systems are difficult to compromise on the economy, flexibility and accuracy. A multi-time scale test system of doubly fed induction generator based on FPGA+ CPU heterogeneous calculation is proposed in this paper. The proposed test system is based on the ADPSS simulation platform. The power circuit part of the test system is setup up using the EMT(electromagnetic transient simulation) simulation, and the control part uses the actual physical devices. In order to realize the close-loop testing for the physical devices, the power circuit must be simulated in real-time. This paper proposes a multi-time scale simulation algorithm, in which the decoupling component divides the power circuit into a large time scale system and a small time scale system in order to reduce computing effort. This paper also proposes the FPGA+CPU heterogeneous computing architecture for implementing this multitime scale simulation. In FPGA, there is a complete small time-scale EMT engine, which support the flexibly circuit modeling with any topology. Finally, the test system is connected to an DFIG controller based on Labview to verify the feasibility of the test system.

Three Types of Spatial Function Zoning in Key Ecological Function Areas Based on Ecological and Economic Coordinated Development: A Case Study of Tacheng Basin, China

Three types of spatial function zoning is an effective measure for regional environmental protection and orderly development.For ecological and economic coordinated development, spatial function zones should be divided scientifically to clear its direction of development and protection. Therefore, based on ecological constraints, a beneficial discussion would be about the key ecological function areas adopting the concept of ecological protection restriction and supporting socioeconomic development for spatial function zoning. In this paper, the researchers, taking Tacheng Basin, Xinjiang of China as an example, choose township as basic research unit and set up an evaluation index system from three aspects, namely, ecological protection suitability, agricultural production suitability, and urban development suitability, which are analyzed by using spatial analysis functions and exclusive matrix method. The results showed that: 1) This paper formed a set of multilevel evaluation index systems for three types of spatial function zoning of the key ecological function areas based on a novel perspective by scientifically dividing Tacheng Basin into ecological space, agricultural space, and urban space,which realized the integration and scientific orientation for spatial function at the township scale. 2) Under the guidance of three types of spatial pattern, the functional orientation and suggestions of development and protection was clearly defined for ecological protection zones,ecological economic zones, agricultural production zones, and urban development zones. 3) A new idea of space governance is provided to promote the coordinated and sustainable development between ecology and economy, which can break the traditional mode of thinking about regional economic development, and offers a scientific basis and reference for macro decision-making.

An optimal strategy for coordinating and dispatching “source-load” in power system based on multiple time scales

Due to the phenomenon of abandoning wind power and photo voltage(PV)power in the“Three Northern Areas”in China,this paper presents an optimal strategy for coordinating and dispatching“source-load”in power system based on multiple time scales.On the basis of the analysis of the uncertainty of wind power and PV power as well as the characteristics of load side resource dispatching,the optimal model of coordinating and dispatching“source-load”in power system based on multiple time scales is established.It can simultaneously and effectively dispatch conventional generators,wind plant,PV power station,pumped-storage power station and load side resources by optimally using three time scales:day-ahead,intra-day and real-time.According to the latest predicted information of wind power,PV power and load,the original generation schedule can be rolled and amended by using the corresponding time scale.The effectiveness of the model can be verified by a real system.The simulation results show that the proposed model can make full use of“source-load”resources to improve the ability to consume wind power and PV power of the grid-connected system.

New scale factor correction scheme for CORDIC algorithm

To overcome the drawbacks such as irregular circuit construction and low system throughput that exist in conventional methods, a new factor correction scheme for coordinate rotation digital computer（ CORDIC） algorithm is proposed. Based on the relationship between the iteration formulae, a new iteration formula is introduced, which leads the correction operation to be several simple shifting and adding operations. As one key part, the effects caused by rounding error are analyzed mathematically and it is concluded that the effects can be degraded by an appropriate selection of coefficients in the iteration formula. The model is then set up in Matlab and coded in Verilog HDL language. The proposed algorithm is also synthesized and verified in field-programmable gate array （FPGA）. The results show that this new scheme requires only one additional clock cycle and there is no change in the elementary iteration for the same precision compared with the conventional algorithm. In addition, the circuit realization is regular and the change in system throughput is very minimal.

Evaluation of Land-Use Efficiency Based on Regional Scale——A Case Study in Zhanjiang,Guangdong Province

Evaluating land use efficiency is critical to the revision of general land use planning. An assessment indicator system for regional land use efficiency was established in this paper from the aspects of society,economy,ecology and environment. The weight of each indicator was defined by an analytical hierarchy process (AHP) and the entropy method (EM). Then,a case study in Zhanjiang was carried out to analyze the regional land use efficiency from 1996 to 2004 and its development by using the method of multifactor composite evaluation and an analytical model of the de-gree of coordination. The results indicate that land use efficiency with respect to society and the economy improved,whereas the ecological and environmental efficiencies were found to decrease. The degree of coordination in Zhanjiang is still at the status of basic coordination. Finally,measures for enhancing the ecological and environmental establish-ment are suggested in order to improve the regulations of land use structure and patterns,establish ecological forests for the public good and green corridors and prevent the soil erosion.

Sewage flow optimization algorithm for large-scale urban sewer networks based on network community division

By considering the flow control of urban sewer networks to minimize the electricity consumption of pumping stations, a decomposition-coordination strategy for energy savings based on network community division is developed in this paper. A mathematical model characterizing the steady-state flow of urban sewer networks is first constructed, consisting of a set of algebraic equations with the structure transportation capacities captured as constraints. Since the sewer networks have no apparent natural hierarchical structure in general, it is very difficult to identify the clustered groups. A fast network division approach through calculating the betweenness of each edge is successfully applied to identify the groups and a sewer network with arbitrary configuration could be then decomposed into subnetworks. By integrating the coupling constraints of the subnetworks, the original problem is separated into N optimization subproblems in accordance with the network decomposition. Each subproblem is solved locally and the solutions to the subproblems are coordinated to form an appropriate global solution. Finally, an application to a specified large-scale sewer network is also investigated to demonstrate the validity of the proposed algorithm.

一种大尺度区域GNSS坐标时间序列自适应时空滤波方法

提出一种GNSS坐标时间序列自适应时空滤波方法,在规定阈值下将滤波区域自适应分为若干个子区域,进行共模误差的提取和去除。对陆态网184个GNSS站点垂向坐标序列进行时空滤波,3组随机实验中,自适应PCA时空滤波后的站点序列平均RMS值减少约39.7%、38.4%和39.7%,且优于整体PCA滤波。进一步分析滤波前后站点噪声特性变化,结果显示,相比于整体PCA滤波,自适应滤波方法中站点残差序列幂律噪声减少约17.8%。

Power Purchase Model of Provincial Grids Based on Diverse Energy Coordination Hedging Optimization

Under the background of energy conservation, the grid companies should give priority to consumptive hydropower, wind power and other clean electricity to fulfill their social responsibility and promote the carbon emission reduction in power industry. But under the current power purchase mode, grid companies must first perform the contract. This is extremely uneconomical and not environmentally friendly. Based on hedging theory, this paper proposes a power purchase optimization model using the strategy of “compression and compensation”. If outer price is lower than the contract price, the grid can compress contract power appropriately, leaving more space for purchasing electricity;if outer price is not attractive enough, the grid should timely improve contract proportion, compensating the deviations of contract caused by "compression". Based on the strategy of "compression and compensation", it can effectively reduce the abandoned wind and water, enhance the economic and social benefits of provincial power grid.

一种发射系下旋转弹的捷联惯导算法

为了提高旋转弹的姿态测量精度,提出了一种发射系下的旋转弹捷联导航算法。首先,推导了发射系导航更新方程;然后,利用传感器测量的前周期角速率对姿态更新算法进行优化,推导了基于角速率的旋转矢量更新算法及其算法误差;最后,采用陀螺仪标度因数的提升方法,实现了捷联惯导姿态测量精度有效的提高。通过对双子样、优化双子样算法在自旋运动条件下的数学仿真、基于转台的半实物仿真试验进行了验证。试验结果表明:在自旋机动条件下,相较于传统双子样算法,基于发射系的旋转弹捷联导航算法具有更高的精度,验证了算法在工程应用实现的正确性和有效性。

基于坐标信息与多尺度并行网络的气道分割方法

为解决手术导航中气道模型精度不足的问题,提出了一种基于坐标信息与多尺度并行网络的气道分割方法。首先通过并行网络分别学习不同尺度的气道特征,以解决不同尺寸气道之间的特征冲突问题。其次提出坐标引导的上采样模块,通过浅层特征中的坐标信息指导深层特征进行特征重建,限制目标的空间位置,提高模型精度。最后提出通道引导的多尺度特征聚合模块,用于在多个尺度上捕获语义信息并探索不同尺度特征之间的通道关系。在公开数据集LIDC-IDRI和EXACT'09上对提出的方法和其他模型进行训练和测试。实验表明,该方法的平均骰子系数达到了93.20%,相比于3D U-Net提高了2.61%,而假阳性率只有0.012%。此外,树长检测率和分支检测率分别达到了88.59%和97.42%。该方法可用于肺部疾病诊断或导航支气管检查等领域。

基于多尺度和加权坐标注意力的轻量化红外道路场景检测模型

针对道路场景下红外目标遮挡、缺乏纹理细节而导致目标误检、漏检的问题,提出一种基于多尺度和加权坐标注意力的轻量化红外道路场景检测模型(MSC-YOLO)。以YOLOv7-tiny作为基线模型,首先,在MobileNetV3的不同中间特征层引入多尺度金字塔模块PSA(Pyramid Split Attention),设计一种多尺度特征提取的轻量化主干提取网络MSM-Net(Multi-Scale Mobile Network),解决固定大小卷积核造成的特征污染问题,提高对于不同尺度目标的细粒度提取能力;其次,在特征融合网络融入加权坐标注意力(WCA)机制,叠加从中间特征图垂直和水平空间方向上获取的目标位置信息,增强目标特征在不同维度上的融合能力;最后,替换定位损失函数为高效交并比(EIoU),分别计算预测框和真实框的长、宽影响因子,提高收敛速度。在Flir数据集上进行验证实验,与YOLOv7-tiny模型相比,在mAP(IoU=0.5)仅降低0.7个百分点的前提下,MSC-YOLO的参数量减少67.3%,浮点运算次数减少54.6%,模型大小减小60.5%,帧率在RTA 2080Ti上达到101,在检测性能和轻量化上达到平衡,满足红外道路场景的实时检测需求。

基于Contextual Transformer的自动驾驶单目3D目标检测

针对当前单目3D目标检测中存在的漏检和多尺度目标检测效果不佳的问题,提出了一种基于Contextual Transformer的自动驾驶单目3D目标检测算法(CM-RTM3D)。在ResNet-50网络中引入Contextual Transformer(CoT),构建ResNet-Transformer架构以提取特征。设计多尺度空间感知模块(MSP),通过尺度空间响应操作改善浅层特征的丢失情况,嵌入沿水平和竖直两个空间方向的坐标注意力机制(CA),使用softmax函数生成各尺度的重要性软权重。在偏移损失中采用Huber损失函数代替L1损失函数。实验结果表明:在KITTI自动驾驶数据集上,相较于RTM3D算法,该算法在简单、中等、困难三个难度级别下,AP3D分别提升了4.84、3.82、5.36个百分点,APBEV分别提升了4.75、6.26、3.56个百分点。

基于滤波器剪枝的多尺度压缩感知图像重构

为了解决低采样率下单尺度采样的压缩感知重构图像纹理细节模糊问题,同时达到使重构网络轻量化的目的,提出了一种基于滤波器剪枝的多尺度压缩感知图像重构网络.采样阶段,通过卷积来模拟图像的线性分解,融合输入图像和不同尺度的分解特征后完成多尺度采样,得到压缩感知测量值.重构阶段,设计了一种基于坐标注意力的多尺度空洞残差模块,将位置信息嵌入通道注意力中,增强网络特征学习的能力.同时通过计算特征图的熵来判断滤波器的重要性,剪除重要性较低的滤波器,达到压缩模型的目的.在DIV2K、Set5、BSDS68和Urban100等数据集上进行训练及测试.实验结果表明,所提算法在峰值信噪比(Peak Signalto-Noise Ratio,PSNR)、结构相似性(Structural Similarity,SSIM)和图像视觉效果上均有提升.其中,采样率为4%,测试集为Set14时,与CSNet+和FSOINet相比,所提算法将重构图像的PSNR分别提高了4.17 dB和2.39 dB,纹理细节更加清晰.在重构效果略微降低的前提下,得到更轻量化的模型,提升了重构速度.

非线性时空正则化的相关滤波目标跟踪算法

针对目标跟踪过程中跟踪模型容易漂移,以及对于多样性形态变化的目标不能进行鲁棒跟踪的问题,结合生物视觉感知规律提出了非线性时空正则化的相关滤波目标跟踪算法。在目标函数中提出贴近人类视觉感知幂定律的非线性滤波更新的时间正则项,相比于时空正则相关滤波器(spatial-temporal regularized correlation filters,STRCF)中固定的时间正则项,非线性滤波更新的时间正则项可以根据跟踪的时间变化进行自适应更新,同时采用交替乘子法降低算法复杂度。提取非线性的梯度方向直方图(histogram of oriented gradient,HOG)特征,使用符合生物映射的对数极坐标进行尺度适应。根据最大响应值与平均峰值相关能量的关系进行遮挡异常检测,降低模型漂移的机率,增强算法的抗遮挡能力。实验结果表明,该算法在OTB2015数据集上的精确率和成功率分别达到89.8%和83.3%,该算法相比于STRCF在精确率上提升了2.5%,在成功率上提升了3.2%,在OTB2013与OTB2015数据集上的11种属性的分类对比中,该算法在旋转、低分辨率、背景杂乱、光照变化等因素干扰下的目标跟踪中具有较高的精确率和较强的鲁棒性。

技术进步能有效促进粮食安全与农民增收双目标实现吗?——来自全国省级面板数据的经验证据

技术进步能显著提高粮食安全与农民增收双目标实现的有效性。论文基于2002—2022年全国31省的面板数据,通过耦合协调度模型、DEA-Malmquist指数模型及面板数据双向固定效应模型等进行实证分析。研究表明:技术进步能明显提高粮食安全与农民收入一致性水平,其中,技术变化对粮食安全与农民收入一致性水平的影响更为显著,该结论在经过一系列稳健性检验后依旧成立。在经济发展水平相对落后的西部地区以及地形更为崎岖的丘陵地区,技术进步对粮食安全与农民收入一致性水平的促进作用更强。此外,技术进步可以通过促进农业适度经营规模水平提升进而间接作用于粮食安全与农民增收双目标的实现。以此为基础,论文提出了相应的政策建议,以充分发挥技术进步对粮食安全与农民增收双目标实现的促进作用。

考虑供需灵活性量化的源-荷-储多时间尺度协同优化

风电、光伏类新能源出力具有随机性和波动性,且随着新能源渗透率的增高,系统灵活性需求也激增。在此背景下,考虑源-荷-储灵活性资源互动,对新能源高渗透系统源-荷-储协同运行问题展开研究。首先,引入向上、向下裕度量化系统灵活性,并利用灵活性供需平衡机理动态评估灵活性需求;其次,提出一种考虑供需灵活性的多时间尺度协同运行方法,构建典型周、典型日、典型时段运行模拟模型,并将碳交易收益和灵活性不足惩罚成本纳入优化目标,考虑调峰需求和爬坡容量对典型时段灵活性的影响,采用多级优化、逐级细化的思路求解模型。算例分析表明,所提方法在保障系统环保性和经济性的基础上,提升了系统各个时间尺度上的灵活性容量,可以促进系统新能源消纳。