High Proportion Renewable Energy Supply and Demand Structure Model and Grid Impaction

In considering of high proportion of renewable energy supply in 2050, the accelerating of energy consumption gross, source and environment can affect the energy system restrict affection are stronger. Add wind and solar to electricity energy with large amount of energy source exploitation. The energy source amount per person is lower. Considering the renewable energy amount and supply, primary energy storage and structure problem is standing out. Before the wide spread of renewable energy, Using the high-carbon energy in China can pollute seriously. Chinese energy supply and demand problem is research key point. This paper researches Chinese energy supply and demand pattern system and evaluation methodology, gives out the inner and outer influencing elements. And evaluate Chinese energy supply and demand pattern from energy gross, structure, distribution and transportation. Use energy supply synthesize radar comparison chart in certain time period. From energy security, economy, clean and efficiency, analyze the benefit comparisons of Chinese energy supply and demand pattern. This energy supply and demand pattern model will give one certain theoretical analysis and practice reference to the further high proportion of renewable energy.

Recent advances of graphene-based materials for high-performance and new-concept supercapacitors

Supercapacitors, with ultrahigh power density, superior rate capability, long-term cyclability, and exceptional safety, are regarded as one highly competitive candidate of electrochemical energy storage devices,filling the gap between batteries and conventional capacitors. Despite of tremendous effort, elaborated screening of high-performance electrode materials, e.g., graphene, is still intensively required. In this review, we describe the most recent progress in the research and development of graphene-based materials for high-performance and new-concept supercapacitors for the targeted applications in next-generation and smart electronics. First, the design and fabrication of high-performance supercapacitors, including electrical double layer capacitors, pseudocapacitors and hybrid supercapacitors, were summarized in term of the charge storage mechanism. Second, new-concept supercapacitors with multiple functionalities of high-voltage, fiber-shape, microscale and shape-diversity in order to fulfill the requirements of future electronics are reviewed. Accordingly, special emphasis is given to the structure-dependent-performance effects of pores, hybridization, dimensionalities of graphene-based materials on performance of supercapacitors, and tremendous potential of graphene-based planar micro-supercapacitors for the direct seamlessly integration with versatile micro-electronics. Finally, perspectives and challenges of graphene-based supercapacitors are briefly discussed.

Phase-Transitions at High, Very High, and Very Low Temperatures upon Nano-Indentations: Onset Forces and Transition Energies

This paper describes the phase-transition energies from published loading curves on the basis of the physically deduced FN = k-h3/2 law that does not violate the energy law by assuming h2 instead, as still do ISO-ASTM 14,577 standards. This law is valid for all materials and all “one-point indentation” temperatures. It detects initial surface effects and phase-transition kink-unsteadiness. Why is that important? The mechanically induced phase-transitions form polymorph interfaces with increased risk of crash nucleation for example at the pickle forks of airliners. After our published crashing risk, as nucleated within microscopic polymorph-interfaces via pre-cracks, had finally appeared (we presented microscopic images (5000×) from a model system), 550 airliners were all at once grounded for 18 months due to such microscopic pre-cracks at their pickle forks (connection device for wing to body). These pre-cracks at phase-transition interfaces were previously not complained at the (semi)yearlycheckups of all airliners. But materials with higher compliance against phase- transitions must be developed for everybody’s safety, most easily by checking with nanoindentations, using their physically correct analyses. Unfortunately, non-physical analyses, as based on the after all incredible exponent 2 on h for the FN versus h loading curve are still enforced by ISO-ASTM standards that cannot detect phase-transitions. These standards propagate that all of the force, as applied to the penetrating cone or pyramid shall be used for the depth formation, but not also in part for the pressure to the indenter environment. However, the remaining part of pressure (that was not consumed for migrations, etc.) is always used for the elastic modulus detection routine. That severely violates the energy-law! Furthermore, the now physically analyzed published loading curves contain the phase-transition onsets and energies information, because these old-fashioned authors innocently (?) published (of course correct) experimental loading curves. These follow as ever the physically deduced FN = k-h3/2 relation that does not violate the energy law. Nevertheless, the old-fashioned authors stubbornly assume h2instead of h3/2 as still do ISO-ASTM 14,577 standards according to an Oliver-Pharr publication of 1992 and textbooks. The present work contributes to understanding the temperature dependence of phase-transitions under mechanical load, not only for aviation and space flights, which is important. The physical calculations use exclusively regressions and pure algebra (no iterations, no fittings, and no simulations) in a series of straightforward steps by correcting for unavoidable initial effects from the axis cuts of the linear branches from the above equation exhibiting sharp kink unsteadiness at the onset of phase transitions. The test loading curves are from Molybdenum and Al 7075 alloy. The valid published loading curves strictly follow the FN = k-h3/2 relation. Full applied work, conversion work, and conversion work per depth unit show reliable overall comparable order of magnitude values at temperature increase by 150°C (Al 7075) and 980°C (Mo) when also considering different physical hardnesses and penetration depths. It turns out how much the normalized endothermic phase-transition energy decreases upon temperature increase. For the only known 1000°C indentation we provide reason that the presented loading curves changes are only to a minor degree caused by the thermal expansion. The results with Al 7075 up to 170°C are successfully compared. Al 7075 alloy is also checked by indentation with liquid nitrogen cooling (77 K). It gives two endothermic and one very prominent exothermic phase transition with particularly high normalized phase-transition energy. This indentation loading curve at liquid nitrogen temperature reveals epochal novelties. The energy requiring endothermic phase transitions (already seen at 20°C and above) at 77 K is shortly after the start of the second polymorph (sharply at 19.53 N loading force) followed by a strongly exothermic phase-transition by producing (that is losing) energy-content. Both processes at 77 K are totally unexpected. The produced energy per depth unit is much higher energy than the one required for the previous endothermic conversions. This exothermic phase-transition profits from the inability to provide further energy for the formation of the third polymorph as endothermic obtained at 70°C and above. That is only possible because the very cold crystal can no longer support endothermic events but supports exothermic ones. Both endothermic and exothermic phase-transitions at 77 K under load are unprecedented and were not expected before. While the energetic support at 77 K for endothermic processes under mechanical load is unusual but still understandable (there are also further means to produce lower temperatures). But strongly exothermicphase-transition under mechanical load for the production of new modification with negative energy content (less than the energy content of the ambient polymorph) at very low temperature is an epochal event here on earth. It leads to new global thinking and promises important new applications. The energy content of strongly exothermic transformed material is less than the thermodynamic standard zero energy-content on earth. And it can only be reached when there is no possibility left to produce an endothermic phase-transition. Such less than zero-energy-content materials should be isolated, using appropriate equipment. Their properties must be investigated by chemists, crystallographers, and physicists for cosmological reasons. It could be that such materials will require cooling despite their low energy content (higher stability!) and not survive at ambient temperatures and pressures on earth, but only because we do not know of such negative-energy-content materials with our arbitrary thermodynamic standard zeros on earth. At first one will have to study how far we can go up with temperature for keeping them stable. Thus, the apparently never before considered unprecedented result opens up new thinking for the search of new polymorphs that can, of course, not be reached by heating. Various further applications including cosmology and space flight explorations are profiting from it.

高比例新能源电网AGC技术研究

为实现区域电网负荷与发电的平衡,确保连续性供电,自动发电控制技术(AGC)近年来得到迅猛发展。基于高比例新能源电网AGC技术应用现状,总结AGC相关控制目标及策略,并结合某域电网实际运行情况,归纳联络线调节、常规断面混合调节与新能源断面调节的控制策略,为AGC技术领域的未来研究提供参考依据。

用于GaN基HEMT栅极金属TiN的ICP刻蚀工艺

GaN基高电子迁移率晶体管(HEMT)在射频(RF)通信及新能源汽车领域有着巨大的应用潜力。TiN材料因其良好的热稳定性、化学稳定性及工艺兼容性,可用作GaN基HEMT的栅极材料。采用ULVAC公司生产的NE-550型电感耦合等离子体(ICP)刻蚀设备对TiN材料进行了干法刻蚀工艺的研究。采用光刻胶作为刻蚀掩膜,Cl_(2)和BCl_(3)混合气体作为工艺气体,通过调整工艺参数,研究了ICP源功率、射频(RF)偏压功率、腔体压力、气体体积流量以及载台温度对TiN刻蚀速率和侧壁角度的影响。最后通过优化工艺参数,得到了TiN刻蚀速率为333 nm/min,底部平整且侧壁角度为81°的栅极结构。

KPI-based Real-time Situational Awareness for Power Systems with a High Proportion of Renewable Energy Sources

With the increasing complexity of power systems and the widespread penetration of renewable energy sources(RES),real-time situational awareness for power systems is of great significance for operational scheduling.Considering the impact of RES on power system operations,a situational awareness key performance index(KPI)system for power systems with a high proportion of RES is proposed in this paper,which consists of reserve capacity abundance,ramp resource abundance,center of inertia(COI)frequency deviation,interface power flow margin,synthesized voltage stability,and angle stability margin.Then,the KPIs are synthesized and visualized by the decision tree method and radar chart method,respectively,for monitoring the operation states(i.e,normal,alert,and emergency states)of power systems with a high proportion of RES.Numerical simulations are conducted in a revised New England 16-machine 68-bus power system and an actual CEPRI-RE power system in the northwest region of China with a high proportion of RES.The results show that the proposed KPI-based situational awareness method is able to accurately monitor the real-time state of power systems with a high proportion of RES,and can assist power dispatchers to make effective decisions.

基于CVaR的高比例光伏区域综合能源系统优化调度

在“双碳”目标的驱动下,以光伏为代表的分布式能源正大规模接入配电系统与配气系统,二者间的耦合也更加紧密,为低碳可持续能源系统的构建带来了新的机遇,然而,由于分布式能源的随机性,其不可避免地造成了两个系统间潜在的运行风险。基于此,本文提出了一种高比例光伏渗透率下区域综合能源系统多时间尺度优化调度模型。首先,在高光伏渗透率的前提下,建立了考虑储能设备的电–气区域综合能源系统日前调度模型,利用二阶锥松弛将模型线性化。其次,基于CVaR风险评估模型的理论基础,建立并简化了损失函数。接着,在实时调度过程中考虑CVaR风险评估模型,建立了考虑CVaR风险评估的区域综合能源系统实时调度模型,以平衡不同风险态度下新能源不确定性导致的风险成本。最后,将上述两个模型合并,建立区域综合能源系统日前–实时多时间尺度调度模型,分析区域电力系统与区域天然气系统之间的相互作用与能量流动。算例分析中,设计了不同的负荷强度方案对模型进行验证,分析了不同方案下系统购电量与不同设备运行参数的变化。结果表明,所提模型可以有效缓解因新能源随机波动带来的运行风险,同时考虑耦合设备的运行调控能够促进区域综合能源系统的耦合运行并取得良好的经济效益。

Single Production of Doubly Charged Higgs Boson via cγCollision in Higgs Triplet Model

The Higgs triplet model（HTM） predicts the existence of a pair of doubly charged Higgs bosons H±±. Single production of H±± via eγcollision at the next generation e+e- International Linear Collider（ILC） and the Large Hadron electron Collider（LHeC） is considered.The numerical results show that the production cross sections are very sensitive to the neutrino oscillation parameters.Their values for the inverted hierarchy mass spectrum are larger than those for the normal hierarchy mass spectrum at these two kinds of collider experiments.With reasonable values of the relevant free parameters,the possible signals of the doubly charged Higgs bosons predicted by the HTM might be detected in future ILC experiments.

西北电网集中式调相机AVC综合协调控制策略

为实现西北电网高比例新能源地区的无功优化控制,提出了一种高压直流换流站集中式调相机参与电网自动电压控制(automatic voltage control,AVC)的综合协调控制策略。首先分析了AVC的总体控制思路,按“软分区”思想构造了三级电压控制模式。针对西北电网和青海电网实际,在网省系统之间建立协调控制变量,结合最优潮流模型,形成了柴达木调相机参与AVC的综合协调控制策略。通过柴达木调相机AVC联调试验时偶遇的电网大扰动实例,验证了控制策略的良好适用性。所提出的AVC控制策略,可使调相机在电网稳态时发挥无功源作用,电网故障时提供瞬时强无功支撑,充分利用新一代调相机性能,提高电网无功电压调节水平。

考虑实时备用率的中长时间尺度新能源发电备用的方法

在新型电力系统中,考虑到中长期时间尺度下新能源出力具有较强规律性,提出了中长时间尺度新能源纳入备用的实时备用率的确定方法。根据实时备用率将新能源可信出力纳入备用,建立多电源电力生产模型。所建模型以生产成本最小为目标函数,考虑电源运行成本、新能源弃电成本、切负荷惩罚成本及机组出力、功率平衡、逻辑变量等约束条件。采用时间迭代将中长时间生产模拟化简为短期优化问题,利用CPLEX求解。以改进IEEE-24节点系统作为算例,优化结果表明新能源电源采用实时备用率的方法纳入备用时,电力系统生产运行总成本更低;新能源渗透率越高,纳入新能源为备用的经济效益越明显;风电和光伏独立确定备用率时,备用成本和污染排放更低。

高比例新能源送端系统暂态电压运行风险分析

针对交、直流故障下的高比例新能源送端系统暂态电压演化传播机理及运行风险尚不明晰的问题,首先,基于交直流系统间的无功电压交互作用机理分析,明确了交、直流系统故障下的暂态电压特性及主导影响因素,阐明了高比例新能源送端系统电力电子设备主导的暂态电压演化传播路径。其次,从“交直流故障强耦合作用持续加强,暂态无功功率成分复杂”、“新能源比例不断提升,暂态电压问题凸显”及“故障承载与调节能力下降,连锁脱网风险增大”三方面系统地阐述了暂态电压运行风险。然后,基于DIgSILENT/PowerFactory建立了实际高比例新能源多直流外送系统仿真模型,不同新能源占比、不同故障工况下的仿真结果验证了暂态电压运行风险分析的正确性。最后,从增强耦合运行特性机理认识、提升新能源涉网性能、增加多尺度协同控制策略、加强交流网架结构等方面提出了应对暂态电压运行风险的技术展望。

一种低电流纹波高增益软开关直流变换器

提出了一种应用于新能源发电系统的低电流纹波高增益软开关直流变换器。在传统交错Boost变换器基础上,该变换器通过引入耦合电感和二极管、电容升压单元提高电压增益,耦合电感在整个开关周期过程中都传递能量,提高了磁芯利用率。输入侧工作在交错模式,两相电感电流纹波可以相互抵消,从而获得较低的输入电流纹波。由于耦合电感自身漏感的存在,减轻了整流二极管反向恢复问题,同时采用有源钳位电路回收利用漏感能量,实现了所有开关管零电压软开关,抑制了开关管关断电压尖峰,提高了变换器转换效率。详细分析了变换器的工作原理、电路特性以及软开关实现方法。最后,搭建了一台200 W的试验样机验证了理论分析的正确性。

基于经济增长视角的山东省新旧动能转换效果评估

坚定不移推动新旧动能转换,是当前山东省推动经济高质量发展的重要任务。基于2008-2021年我国30个省级行政区的面板数据,将除山东省以外的其他省(区、市)作为潜在控制组,从经济增长的视角,采用合成控制法,对山东省新旧动能转换重大工程的实施效果进行评估。结果表明,从整体上来说,新旧动能转换重大工程的实施对山东省经济增长具有显著的促进作用,但这种作用的显现具有时间滞后性,并且不同因素对山东省新旧动能转换重大工程的影响具有差异性。因此,要深刻认识和把握新旧动能转换的演进过程,大力推动供需两侧新动能培育和成长等。

水电高占比下风电接入对系统稳定性影响

随着绿色清洁高效能源基地的构建,以水电为主体的水风互补成为我国西南能源开发的重要特征。为研究在典型水电系统中接入风电对系统稳定性带来的影响,首先,针对水风互补系统以转矩分析法分析了风电接入对系统频率和功角稳定性的影响,并通过算例和Prony分析验证了风速与风电渗透率对系统稳定性的影响。结果表明,风电的接入在一定程度上可以削弱传统水电系统的超低频振荡,而风电接入互联送端系统会导致区域等值惯量的下降,进而使系统区域间低频振荡风险加剧。其次,考虑风电的接入会诱发区域间低频振荡,在风电系统中引入风电的附加综合虚拟惯性与阻尼控制。算例与Prony分析验证了该控制策略能有效提高系统稳定性。最后,在区域间大规模风电接入场景下,利用改进的鲸鱼算法对风电的附加控制器参数进行了优化;结果表明,参数的整定有效提高了系统的频率以及功角稳定性。

新能源在高质量发展中的全要素生产率贡献研究

新能源作为具有高科技、高效能、高质量特征的新质生产力,催生能源领域的新产业、新模式、新动能,带动全要素生产率提升。在测度中国全要素生产率、全要素能源效率和绿色全要素新能源效率及其变化率基础上,分析新能源技术效率对全要素生产率变化的贡献。研究表明,提升新能源效率不仅有利于增强新能源对传统能源的竞争优势,助推能源结构绿色市场化转型,而且有利于提高全要素生产率,因此有必要以持续创新加快新能源技术进步和技术效率提升,以更高的新能源效率促进能源结构绿色转型,助力经济高质量发展。

中国经济实现“稳”与“进”的策略选择

处理好我国经济发展“稳”与“进”的关系是实现经济高质量发展、扎实推进中国式现代化的重要思想方法。高水平安全体系为我国经济发展提供了保障,是实现“稳”与“进”的基础;新能源产业发展助力经济转型升级和提质增效,是实现“稳”与“进”的新生动力;区域协调发展有助于解决经济发展不平衡问题,是实现“稳”与“进”的内在驱动;高水平对外开放能够提升经济竞争力和国际竞争力,是实现“稳”与“进”的外部条件。这四个方面相互促进、相辅相成,共同构成推动经济高质量发展的强大动力。

Double-uncertainty optimal operation of hybrid AC/DC microgrids with high proportion of intermittent energy sources

This paper applies double-uncertainty optimization theory to the operation of AC/DC hybrid microgrids to deal with uncertainties caused by a high proportion of intermittent energy sources.A fuzzy stochastic expectation economic model for day-ahead scheduling based on uncertain optimization theory is proposed to minimize the operational costs of hybrid AC/DC microgrids.The fuzzy stochastic alternating direction multiplier method is proposed to solve the double-uncertainty optimization problem.A real-time intra-day unbalanced power adjustment model is established to minimize real-time adjustment costs.Through comparative analysis of deterministic optimization,stochastic optimization and fuzzy stochastic optimization of day-ahead scheduling and real-time adjustment,the validity of fuzzy stochastic optimization based on a fuzzy stochastic expectation model is proved.

“双高计划”背景下新能源汽车技术专业群建设探索与实践

建设高水平新能源汽车技术专业群是加强高素质技术技能人才培养工作、实施国家和地方新能源汽车发展战略的重要举措,文章以福州职业技术学院新能源汽车技术专业群为例,分析了专业群的构建思路,阐述了对专业群建设内容的探索与实践情况,为职业教育积极服务区域行业经济发展提供参考。

含规模氢能综合利用的高比例风光多能源系统低碳灵活调度

随着风光等间歇性可再生能源大规模增长和并网,可再生能源弃能率升高与系统备用灵活性问题日益突出,为解决高比例可再生能源科学消纳与能源系统灵活稳定运行问题,该文提出一种含规模氢能综合利用的高比例风光多能源系统低碳灵活调度方法。针对电制氢、氢燃料电池、甲烷反应器等组成的氢能综合利用单元进行机理分析并建模,研究该单元参与多能源系统运行的调度策略;对该单元各设备的备用能力进行分析,基于各设备的运行特性,提出氢能利用单元–火电联合承担备用的策略,并建立备用优化模型;最后在改进的IEEE39节点电网、20节点气网和6节点热网构成的多能源系统中进行对比仿真分析,验证所提调度方法促进高比例风光消纳和提供灵活性备用的能力。

一种概率-Voronoi自适应高维模型表达的新能源电力系统小干扰失稳风险评估方法

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