基于状态快速排序法的电网可靠性灵敏度计算

电力系统的可靠性灵敏度分析能识别电网的薄弱环节,通过对电网可靠性水平进行量化评估为规划提供参考。采用状态快速排序法来选取系统的状态空间,建立了基于状态空间的灵敏度计算模型,将灵敏度的计算过程与状态空间割裂开来,可根据确定的空间进行灵敏度分析。此方法实现了灵敏度高效计算。最后以IEEE-RTS79算例进行分析,并与截止故障重数方法进行了比对,验证了基于状态快速筛选的灵敏度计算方法的高效性。     

Optimal location and parameter setting of UPFC for enhancing power system security based on Differential Evolution algorithm

This paper presents a new approach based on Differential Evolution (DE) technique to find out the optimal placement and parameter setting of Unified Power Flow Controller (UPFC) for enhancing power system security under single line contingencies. Firstly, we perform a contingency analysis and ranking process to determine the most severe line outage contingencies considering line overloads and bus voltage limit violations as a Performance Index. Secondly, we apply DE technique to find out the optimal location and parameter setting of UPFC under the determined contingency scenarios. To verify our proposed approach, we perform simulations on an IEEE 14-bus and an IEEE 30-bus power systems. The results we have obtained indicate that installing UPFC in the location optimized by DE can significantly enhance the security of power system by eliminating or minimizing the overloaded lines and the bus voltage limit violations.     

Electroless plating of moisture‐curable polyurethane undercoating films

The compatibility of using moisture‐curable polyurethane (MCPU) system as a thin undercoating layer with electroless plating process was evaluated. The characteristics of the MCPU before and after chemical etching treatment were analyzed using atomic force microscope (AFM), scanning electrode microscope (SEM), contact‐angle measurements, and (Fourier‐Transform Infrared) FTIR spectroscopy. We found that surface morphology and roughness of the MCPU is affected by curing period and etching times. A proper combination of curing period and etching times are critical for obtaining a fully metallized surface. All MCPU samples that were etched for 15 min show poor plating performance due to surface damage caused by mild etching treatment. A standard pull‐off testing method (ASTM 4541) was used to evaluate the adhesion strength of nickel–MCPU. Only samples that were postcured for 4 days show influence of surface roughness on adhesion strength. On average, samples that were postcured for 7 days before electroless plating showed better adhesion of nickel–MCPU compared with samples that were postcured for 2 or 4 days. The results show that MCPU system can be used as a thin undercoating layer for electroless plating. It also offers smooth metal–polymer interface and therefore has the potential to be exploited for use in many electroless plating applications including in the decorative such as ornaments and display items and also in electronic industries. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1554–1565, 2007     

市场环境下共享汽车电池仓库能量管理策略研究

共享电动汽车是未来交通出行的发展趋势。将换电模式应用于共享电动汽车,在保持其换电便捷性优势的同时可以解决电池统一性的问题,具有良好的发展前景。文章对换电模式下共享电动汽车运营商管理的电池仓库开展研究,提出了能量优化管理的双层规划模型。上层以电池仓库成本最小化为目标对电池充放电功率进行优化,下层对电池仓库参与电力市场的出清过程进行建模,然后基于KKT条件和强对偶理论将模型转换成混合整数线性规划问题进行求解。最后,通过算例分析电池仓库的竞价和能量管理策略,验证了文中所提模型可以在满足共享用户电池需求的同时,降低共享汽车电池仓库的运营成本。     

基于统计分析的风-气能源基地远距离直流输电方案规划

风电资源的大规模开发及天然气在一次能源的消费比重不断提高,给电力系统规划和运行带来新的挑战。为将大容量风电输送到数千千米外的负荷中心,采用具有远距离、大容量、低损耗输电能力的特高压直流输电系统。针对含丰富风电和天然气资源的能源基地远距离输电,提出了基于置信水平的风-气输电容量统计分析方法,综合考虑源端风-气综合能源出力的随机性、输电方案的经济技术环境及受端系统承受能力等方面的因素,构建了风-气能源基地的远距离直流输电评估指标体系,并基于改进前景理论法对风-气远距离直流输电系统候选方案进行综合优选。在算例分析中,通过灵敏度方法分析了不同输电方案的适用范围,并验证了所提规划方案的优越性,为大容量能源远距离直流输送规划的科学决策提供参考。