基于AHP的产品概念设计研究

产品概念设计的基本目的是获得综合性能最好的设计方案。通过对产品功能的分解和结构要素的映射分析,求出的方案集的解,通过分析不同方案对功能要素的相对重要度大小并进行量化处理,再基于AHP进行归纳计算,找到综合权重最大的方案作为最佳设计方案。通过对电缆除冰装置概念设计的实例分析和计算,验证了该方法在产品概念设计方面应用的可行性和实用性。     

A Highly Transparent Photo-Electro-Thermal Film with Broadband Selectivity for All-Day Anti-/De-Icing

A photo- and electro-thermal film can convert sunlight and electricity into heat to solve icing problems. Combination of them provides an efficient strategy for all-day anti-/de-icing. However, only opaque surfaces have been reported, due to the mutual exclusiveness between photon absorption and transmission. Herein, a highly transparent and scalable solution-processed photo-electro-thermal film is reported, which exhibits an ultra-broadband selective spectrum to separate the visible light from sunlight and a countertrend suppress of emission in longer wavelength. It absorbs ≈ 85% of invisible sunlight (ultraviolet and near-infrared) for light-heat conversion, meanwhile maintains luminous transmittance > 70%. The reflection of mid-infrared leads to low emissivity (0.41), which further preserves heat on the surface for anti-/de-icing purpose. This ultra-broadband selectivity enables temperature elevation > 40 °C under 1-sun illumination and the mutual support between photo-thermal and electro-thermal effects contributes to > 50% saving of electrical consumption under weak solar exposure (0.4-sun) for maintaining unfrozen surfaces at −35 °C environment. The reverberation from photo-electro-thermal and super-hydrophobic effects illustrates a lubricating removal of grown ice in short time (< 120 s). The self-cleaning ability and the durability under mechanical, electrical, optical, and thermal stresses render the film stable for long-term usage in all-day anti-/de-icing applications.     

液滴撞击疏水/超疏水表面防结冰技术研究进展及未来展望

抑制撞击液滴的结冰在实际工程应用中具有重要意义。寻求经济、高效的防/除冰方法是结冰领域的研究热点。针对撞击液滴的结冰问题,首先从动力学特性、结冰特性以及撞击液滴结冰的理论研究等方面进行综述,并对目前关于撞击液滴结冰中存在的一些问题进行分析。然后,基于撞击液滴的反弹特性可从源头上抑制结冰这种思路,提出降低接触时间、增加成核再辉时间的新方法。这些方法的提出有助于从源头上解决撞击液滴的结冰问题,将使“利用撞击液滴的反弹特性抑制结冰”的应用范围极大扩展,积极推动防结冰技术的发展。最后,对利用液滴的反弹特性进行抑制结冰的研究进行展望。     

基于粗糙集和主成分分析法的电网融冰决策方法

基于粗糙集和主成分分析法建立冰灾数据规则和冰灾应急处理融冰效率函数,提出一种电网冰灾融冰决策新方法．以湖南电网为例,分别运用MATLAB和SPSS软件进行粗糙集和主成分分析法的计算,划分湖南地区覆冰严重程度顺序并建立了融冰效率函数,得到湖南电网效率最高融冰手段,实现输电线路融冰的优化决策．     

Simultaneous effects of salted water and water flow on asphalt concrete pavement deterioration under freeze–thaw cycles

The presence of water flow on road surfaces may lead to early deterioration of bituminous pavements. The adverse impacts of various anti-freezing materials on road surface performance have drawn the attention of many researchers. However, the simultaneous effects of salted water and water flow on the deterioration of road surfaces, particularly under freeze–thaw conditions, have not been adequately addressed. This research aims to study the combined effects of water flow and anti-freezing materials, which are usually present in the vicinity of asphaltic pavements during freeze–thaw cycles, on asphalt concrete deterioration. Two sets of asphalt concrete samples were prepared and subjected to six exposure states. The samples were also tested in an abrasion test apparatus and subjected to normal and frictional forces. Marshall strength loss and weight loss of the samples were measured and the results were analysed. The results indicated that the combined effects of water flow and de-icers under freeze–thaw conditions intensified the deterioration of asphalt concrete.     

不可控12脉波整流的输电线路直流融冰研究

在覆冰输电线路的融冰方法中,与传统的交流融冰法和机械除冰法相比,直流融冰法具有所需电源容量小、高效、方便等优势。研究了采用不可控12脉波整流的直流融冰方法,分析了不可控12脉波整流直流融冰原理,在确定相应型号导线融冰电流的基础上,计算出实现导线融冰所需的融冰电压和交流侧电压,并由此确定整流变压器的额定电压比,分别推导出上下整流桥串／并联两种接线方式条件下覆冰导线的可融长度。仿真结果表明,该方法在不同型号导线的一定长度范围内具有良好的融冰效果,为解决输电线路覆冰问题提供了一种可靠技术。     

输电线路的交流冲击短路融冰方案研究

介绍了输电线路交流冲击短路融冰方法的原理,给出了交流冲击短路融冰方案编制的流程,并对融冰方案编制时融冰路径的选择方法、方案计算和方案校核及相关继电保护的配合等问题进行了详细分析,最后针对桂林电网的一条110 kV线路进行了交流冲击短路融冰方案设计,为其他地区制定交流冲击短路融冰方案提供借鉴。     

基于蒙特卡罗方法的除冰机器人作业空间边界提取

设计了一种输电线路除冰机器人的机械结构, 分析了该机构的作业空间问题. 在计算过程中, 引入Monte Carlo方法得到了机器人操作臂的工作空间. 采用该方法可避免对机器人运动方程的求逆解计算, 极大地简化了计算过程. 分析并指出传统的机器人工作空间边界提取方法精度有限, 且存在理论上的缺陷; 提出了一种新的基于局部点象限分布的边界点提取方法, 文中给出的算例表明, 该方法不仅精度高, 并且非常适合于处理机器人工作空间边界问题.     

输电线路除冰机器人行为控制研究

介绍了输电线路除冰机器人的研究现状.针对其工作环境恶劣、不确定因素多的特点,提出了基于马尔可夫决策的行为控制器的设计方法.该方法首先定义了输电线除冰机器人的马尔可夫模型,然后给出了相应的最优方针搜索策略,还给控制器添加了概率调节机制,以达到执行效果反馈的目的.为解决机器人作业中的突发情况,在该方法中还引入了人工辅助和行...     

应对极端冰灾的电力系统多阶段韧性提升策略

为提升冰灾下电力系统的韧性,降低系统负荷削减量,提高系统恢复速率,提出一种应对极端冰灾的电力系统多阶段韧性提升策略。对冰灾场景以及受冰灾影响的线路故障率进行建模;从线路抗冰能力、系统负荷损失、系统恢复情况、线路受损情况、维修资源充裕度多个角度构建电力系统综合韧性评估指标,以定位冰灾下系统的薄弱环节;在此基础上,通过灾前线路故障风险预测、灾中机组出力调整以及除冰线路筛选和主动停运除冰、灾后维修顺序规划等策略提升冰灾下的系统韧性。基于IEEE 39和IEEE 118节点系统进行仿真分析,结果验证了所提韧性评估方法和提升策略的有效性。