Approach of Training Working Staff of Power System Operation Mode Based on State Evaluation

An approach of training working staff of power system operation mode based on state evaluation is proposed. In terms of knowledge features of power system operation mode, we studied a training method based on evaluation of learning state. This training method makes individual learning for different individual condition to give them ability to grasp learning points quickly, evaluate real-time learning effect, update learning style in time and summarize problems after one learning stage, so that learners can master professional knowledge in constant summaries and feedbacks. Obvious effects can be obtained on discontinuous learning time that trainees can master basic theories associated with their working and operations adapted to practical work quickly.

Study on integrated development and hybrid operation mode of nuclear power plant and pumped-storage power station

The nuclear power plant is suitable for base-load operation, while the pumped-storage unit mainly gives play to capacity benefit in the electric power system;hence, the integrated development and hybrid operation mode of the two can better meet the needs of the electric power system. This article first presents an analysis of the necessity and superiority of such mode, then explains its meaning and analyzes the working routes. Finally, it proposes the business modes as follows: low price pumping water electricity plus nuclear power in the near term;nuclear power shifted to pumped storage power participating in market competition in the middle term;and, in the long term, nuclear power shifted to pumped storage power as primary and serving as an electric power system when needed.

Low Power Consumption Distributed-Feedback Quantum Cascade Lasers Operating in Continuous-Wave Mode above 90℃ at λ～7.2μm

We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. For a 2-mm-long and 10-μm-wide laser coated with high-reflectivity on the rear facet, more than 170mW of output power is obtained at 20℃ with a threshold power consumption of 2.4 W, corresponding to 30mW with a threshold power consumption of 3.9 W at 90℃. Robust single-mode emission with a side-mode suppression ratio above 25 dB is continuously tunable by the heat sink temperature or injection current.

Analysis of Switching Overvoltage in Regional Grid with Small Hydropower Plants

Present-day small hydropower plants (SHPs) have a large development potential because of the increasing interest in renewable resources and distributed energy generation, therefore, there are many SHPs in places of China where are rich in water resources. However, it has caused overvoltages in the distribution network, and which is even worse for the switching overvoltage such as isolated network operation, changing power supply path. The simple network model is used to analyze the reasons of the switching overvoltage, and the simulation software DIgSILENT/PowerFactory is used to check out the results of the theoretical analysis.

Cascade utilization of full spectrum solar energy for achieving simultaneous hydrogen production and all-day thermoelectric conversion

Solar-driven photocatalytic water/seawater splitting holds great potential for green hydrogen production.However,the practical application is hindered by the relatively low conversion efficiency resulting from the inadequate utilization of solar spectrum with significant waste in the form of heat.Moreover,current equipment struggles to maintain all-day operation subjected to the lack of light during nighttime.Herein,a novel hybrid system integrating photothermal catalytic(PTC)reactor,thermoelectric generator(TEG),and phase change materials(PCM)was proposed and designed(named as PTC-TEG-PCM)to address these challenges and enable simultaneous overall seawater splitting and 24-hour power generation.The PTC system effectively maintains in an optimal temperature range to maximize photothermal-assisted photocatalytic hydrogen production.The TEG component recycles the low-grade waste heat for power generation,complementing the shortcoming of photocatalytic conversion and achieving cascade utilization of full-spectrum solar energy.Furthermore,exceptional thermal storage capability of PCM allow for the conversion of released heat into electricity during nighttime,contributing significantly to the overall power output and enabling PTC-TEG-PCM to operate for more than 12 h under the actual condition.Compared to traditional PTC system,the overall energy conversion efficiency of the PTC-TEG-PCM system can be increased by∼500%,while maintaining the solar-to-hydrogen efficiency.The advancement of this novel system demonstrated that recycling waste heat from the PTC system and utilizing heat absorption/release capability of PCM for thermoelectric application are effective strategies to improve solar energy conversion.With flexible parameter designing,PTC-TEG-PCM can be applied in various scenarios,offering high efficiency,stability,and sustainability.

Offshore Wind Power Evaluation Based on Nearshore Wind Power Correlations

As the increasing number of wind energy is integrated into the national power grid,analyses of wind energy are becoming increasingly more crucial.The interaction between the topography and the northeast(NE)monsoon brings abundant wind resources to the Taiwan Strait in autumn and winter.The offshore area has stronger and more stable wind resources,so deployment of offshore wind power is also actively being carried out.However,development of offshore wind power systems requires stricter evaluation and decision-making.Therefore,this study implements a multi-site measurement verification to establish the relationship between the wind resources of the nearshore wind turbine system and a potential offshore power site in Chanbin.In the absence of a wind turbine at a specific location,potential of offshore wind energy is analyzed through wind resources.The findings showed that although the distance between these two sites is substantial,the nearshore and offshore areas at Chanbin experience similar wind conditions,and nearshore wind turbine can respond well to changes in wind speed and generate power accordingly.Afterwards,on this basis,the offshore power potential was evaluated and compared with the nearshore wind turbine systems.The results suggested the advantages of offshore wind power.A further analysis of the differences between power generation on a monthly basis was carried out to determine the distribution of wind turbine operation modes and illustrate the influence of the NE monsoon.

Core Size Scaling of Helical-Core Optical Fibres

The mode-area scaling properties of helical-core optical fibres are numerically studied and the limit of core size for achievable single-mode operation is explored. By appropriate design, helical-core fibres can operate in a single mode with possible scaling up to 300μm in core diameter with numerical aperture 0.1.

“人-车-桩-路-网”深度耦合下的配电网协同规划与运行优化

电动汽车(EV)作为连接交通电气化和电网清洁化的纽带和桥梁,可实现电力-交通-信息之间的深度耦合,形成电力-交通一体化的规划及运行架构。配电-交通融合系统(DTIS)中,EV充放电行为多时空动态交织、电能流-交通流-信息流深度融合、多利益主体动态博弈等大量不确定性因素使配电网的规划及运行优化的边界都将发生重大转变,但同时也给挖掘利用EV的移动储能特性和提升配电网灵活性带来了契机。为此,在分析“人-车-桩-路-网”深度耦合下配电网的形态演化特征基础上,剖析了新形态下配电网协同规划与运行优化所面临的新挑战,进而针对“人-车-桩-路-网”耦合下的EV灵活性建模、灵活域高效构建及预测、协同规划、运行优化4个方面关键技术展开讨论,并对相关技术问题的研究方向进行了展望。

三门峡水库控制运用方式的优化探讨

三门峡水库“蓄清排浑”运用为多沙河流的治理提供了宝贵经验,随着来水来沙情况的变化及对水库功能需求和对水库泥沙冲淤规律认识的深化,该运行方式亦在实践中不断调整和完善。为此,针对不同的典型年份设定集中敞泄与分段敞泄的敞泄排沙方案,采用一维非恒定水沙数学模型,对选取的2018~2019年丰水少沙年和2014~2016年枯水少沙年设定12种控制运用方案进行模拟,比较各方案下库区冲淤变化的优劣,据此选取适合三门峡水库的控制运用方式。结果表明,2018~2019年分段敞泄方案的冲刷效果优于集中敞泄方案,即使在后汛期的控制水位抬高至310 m,也能达到较好的冲刷效果;2014~2016年分段敞泄方案虽优于集中敞泄方案,但其冲刷主要集中于2014年汛期,2015、2016年整体呈淤积状态,综合考虑建议枯水少沙年份水库采用“泥沙年际调节”运用模式。

基于凸包算法的极端运行方式提取方法

在电力系统规划与运行的安全稳定计算中,一般选择对安全稳定最不利的运行方式进行校验,但随着新能源渗透率的增加,电网越发复杂多变,人工选择场景主观性较强,针对此问题,提出了一种基于快速凸包算法的极端运行方式提取,从而满足场景选取进行安全校核需求。从电源规划、发输电协调规划两个角度,考虑发电充裕性、火电爬坡需求、网络传输安全3个方面,分析影响规划的极端运行方式;基于凸包算法分别从上述3个方面构建坐标系进行极端运行方式提取;采用中国西北地区电网为算例进行极端运行方式提取,并与基于K-means算法的极端场景提取做对比,结果表明:所提方法能为场景选取提供有效数据支撑,满足电网规划要求。

基于EnKF的水光互补系统适应性调度规则敏感性分析

水光互补是解决电力能源供应问题、构建低碳能源体系、实现“双碳”目标的重要举措。采用集合卡尔曼滤波对线性调度函数的参数进行动态更新,构建了水光互补中长期适应性调度规则,并以龙羊峡水光互补电站为研究对象,在同化过程中引入预测误差、观测误差及集合规模3个不确定性参数,分析了不确定性参数取值对模型时变参数和运行结果的影响,并对参数的敏感性进行了定性分析。结果表明,预测误差、观测误差及集合规模对模型时变参数和运行结果没有显著影响,三者均不是敏感性参数。研究结果可为集合卡尔曼滤波参数不确定性分析及多能互补系统适应性调度研究提供参考。

摇摆、操作方式对数字化主控室操作员点击操作绩效的影响

目的了解摇摆、操作方式对数字化核电厂主控室操作员点击操作的影响,降低人因失误。方法设计并组织蒸汽发生器传热管道破裂事故下操作员点击操作实验,探究4种摇摆级别(静止、低、中和高)×2操作方式(鼠标和轨迹球)下操作员点击操作绩效。结果摇摆对反应时间和正确率影响均不显著,操作方式对正确率影响不显著,但显著影响反应时间。随着摇摆级别的增加,不适程度增加,但不同操作方式下,摇摆不适差异不显著。不同摇摆级别下,操作主观评分差异不显著,与鼠标相比,轨迹球较难操作,用力更大,指向准确性较差,操作速度相对较慢,整体舒适度较低,可用性相对较差。结论本研究中摇摆对数字化主控室操作员点击操作绩效影响小,操作方式影响操作绩效,且使用轨迹球时所需反应时间增加,约为鼠标的1.51倍。

井下电力电缆故障定位研究

针对传统井下电力电缆故障定位方法依赖主观参数选择和抗噪性能较差,无法满足强噪声背景下井下电力电缆故障精确定位要求的问题,提出了一种基于樽海鞘群算法(SSA)优化变分模态分解(VMD)并结合改进型Teager能量算子(NTEO)的井下电力电缆故障定位方法。针对VMD在信号分解上存在的模态混叠、过分解和欠分解问题,采用SSA以模糊熵为适应度函数对VMD模态数K和惩罚因子α2个参数进行优化,得到更能反映故障特征信息的本征模态函数;采用NTEO对本征模态函数进行首波波头标定,得到首末两端的波头到达时刻,根据双端测距法得出故障位置。采用PSCAD/EMTDC进行井下电力电缆故障仿真,模拟具有强背景噪声的井下故障信号,结果表明:①在理想电流信号中加入9,12 dB噪声后,SSA-VMD的信噪比最低,皮尔逊相关系数最大,说明SSA-VMD在最大程度降噪的同时,能很好地保留信号的特征信息。②在不同过渡电阻下,SSA-VMD-NTEO的定位精度较高。③在不同故障相角下,SSA-VMD-NTEO在采样点上出现不同,但定位位置没有改变,依旧保持较高的定位精度。④在不同故障距离下,SSA-VMD-NTEO均能保证较高的定位精度。⑤在井下较大噪声和10 MHz采样频率下,SSA-VMD-NTEO较小波模极大值和VMD+NTEO 2种方法的定位精度具有明显优势。

成渝中线铁路双边供电牵引网接线方案研究

成渝中线综合试验段作为CR450科技创新工程的示范应用线路,将开行CR450新型动车组。CR450动车组功率的提升对牵引供电系统供电能力提出了更高要求,因此《成渝中线高速铁路设计暂行规范》提出“条件允许时可采用双边供电方式”。本文分析了牵引供电系统双边供电方式下牵引网3种接线方案及运行方式,对比优缺点,明确了成渝中线双边供电牵引网接线方案,并就不同接线方案工程适应性提出建议。

混合工作模态的高功率因数无桥Buck PFC变换器

AC-DC降压型功率因数校正PFC(power factor correction)变换器广泛应用于低压场合,为解决该类拓扑因输入电流死区导致功率因数PF(power factor)低、输入电流总谐波THDi(total harmonic distortions of input current)高的问题,首先引入Buck-Boost单元以构建1种高PF的混合工作模态降压型无桥PFC变换器,其在正、负半个工频周期分别工作在Buck和Buck-Boost模式。虽然Buck-Boost单元效率低于Buck单元,但所提变换器在负半工频周期运行于Buck-Boost模式,可以避免输入电流死区以提高PF并降低THDi。在正半工频周期运行于Buck模式,变换器仍保留Buck单元的高效率优势。其次,通过分析所提无桥变换器工作模态与PF值来证明变换器的高PF特性。最后,通过仿真实验,验证所提变换器的可行性和理论分析的正确性,并比较所提变换器与传统Buck PFC变换器的性能。

计及碳交易的热电联产-储热-电锅炉风电消纳策略

为解决传统热电联产机组的热电耦合特性以及冬季采暖期间弃风消纳问题,提出了计及碳交易含储热热电联产机组和电锅炉联合运行的弃风消纳策略。首先将储热设备、电锅炉与热电联产机组联合运行来满足系统所需热负荷,从而提高热电联产机组电调峰能力。其次,为进一步控制碳排放量,引入阶梯式碳交易与优化电锅炉运行模式,兼顾系统运行成本、弃风消纳量以及碳排放量,构建计及碳交易的热电联产-储热-电锅炉风电消纳模型并进行求解。最后,以IEEE-30节点为例进行算例分析,结果表明所提策略能够有效促进风电消纳、减少碳排放量且有效降低系统运行成本。

多时间尺度下计及综合需求响应和碳捕集-电转气联合运行的综合能源系统优化调度

对源侧进行低碳化改造、荷侧辅以综合需求响应策略有利于“双碳”目标的实现。为此,提出一种多时间尺度下计及综合需求响应和碳捕集-电转气联合运行的综合能源系统低碳优化调度策略。源侧在碳捕集电厂中引入储液罐,形成碳捕集电厂的综合灵活运行方式,并构建计及碳捕集电厂和电转气设备的新型联合运行模型;在荷侧分析需求侧资源在不同时间尺度下的响应特性,建立不同时间尺度下的价格型、激励型需求响应模型,通过源荷协调配合提升系统的低碳性能;提出源荷互补的综合能源系统多时间尺度低碳调度策略,构建含综合需求响应的日前-日内-实时调度模型。算例结果表明,所提模型能够充分利用源荷资源参与调节,实现系统低碳、经济、稳定运行。

职业教育强国建设的支撑体系:结构、机理与优化

作为一项系统性、整体性工程,职业教育强国建设需要强有力、全方位的支撑体系。基于系统结构的层次性特征,这一体系主要包括基础层、运行层和保障层等。其是由理论性、物质性、文化性、社会性、政策性、组织性和师资性等支撑要素构成的有机整体。根据主体职责分工的不同,这一体系可以划分为党和政府的主导建构、各级各类职业院校的主体建构、代表社会力量的行业企业参与建构三种主要运行模式。基于此,要大力推进职业教育强国建设,必须对其支撑体系的要素输入、处理和输出环节进行整合优化。既要充分挖掘符合职教类型发展定位的多重支撑要素,也要着力形成协同发展机制、实践转化机制、信息反馈机制和效能评价机制等,使各类支撑要素整合在呈现帕累托最优效应的基础上推进职业教育强国建设不断取得新进展新成效。

拉萨河流域梯级电站水光互补调度对水文情势的影响分析

梯级电站水光互补调度能提高光伏消纳能力和系统总发电量,但也要求调整梯级电站的调度规则,进而会加剧梯级电站下游的水文情势改变。为定量评价水光互补调度对水文情势的影响,以系统总发电量和总保证出力最大为目标,构建了拉萨河流域梯级电站水光互补优化调度模型,提出了基于水光互补的梯级电站优化调度方案,分析评价了不同优化调度方案的水文情势改变度。结果表明:梯级电站的水光互补优化调度能有效提升电力系统的总发电量和总保证出力;水光互补后拉萨河水文情势的综合改变度略大于水光互补之前,处于轻度至中度改变的临界值附近。研究成果可为拉萨河的水光互补调度及流域综合管理提供科学方法和依据。

面向可持续发展的数字乡村建设:困境与出路

随着数字乡村建设从政策文本层面进入到实质性推动阶段,数字乡村可持续发展的模式与路径问题已经上升为新发展阶段数字乡村建设的核心议题之一。当前,我国数字乡村建设已经初步形成了一个以政府投资运维管理模式为主导,政企合作运维管理模式和企业主体建设运维管理模式点状散发的模式结构,造成了我国目前数字乡村建设运维模式的结构性失衡,而数字下乡的“水土不服”是导致数字乡村可持续发展困境的根源性因素。面向可持续发展目标,应从因地制宜做好系统性规划、加大专项支持力度、构建多元协同建设运维机制、提升主体素养和扩大试点示范建设等5个方面开展路径谋划。