基于87C196实现的快速无功电流检测

提出了电力系统无功电流的ip-iq检测方案，给出了用87C196单片机实现无功电流实时检测的具体方法，该检测系统不但可以快速准确地进行无功检测，同时还可以配合TSC系统对系统无功电流进行动态补偿。     

静止无功补偿装置在输电系统中的应用

阐述了静止无功补偿装置（SVC）对改善电网枢纽点的电压控制;提高静态和暂态稳定性,增加输电能力;抑制系统暂时（工频）过电压;增加阻尼,抑制低频和次同步振荡,提高输电功率;改善直流换流站动态无功补偿性能等功能,以及在国内外高压输电系统中的应用情况,并给出了应用实例.我国电网正处在快速发展阶段,随着输电系统SVC技术国产化的成功,SVC在国内电网中的应用会有广阔前景.     

天钢集团中板厂SVC动态无功补偿和谐波滤波系统

天津钢铁集团中板厂的负载为冲击性交-交变频机,交-交变频机的谐波除了特征谐波外,还有大量旁频。电网中谐波电流大,功率因数低,电压波动超标。SVC系统为FC TCR系统,通过测试负载电流和普通直流机负载电流,分析频率特性,得出交交变频机的谐波滤波可以按照直流机的滤波装置来设计,同时TCR本身产生的谐波必须予以考虑。     

Probabilistic approach to multi-objective Volt/Var control of distribution system considering hybrid fuel cell and wind energy sources using Improved Shuffled Frog Leaping Algorithm

Deregulation and restructuring in power systems, the ever-increasing demand for electricity, and concerns about the environment are the major driving forces for using Renewable Energy Sources (RES). Recently, Wind Farms (WFs) and Fuel Cell Power Plants (FCPPs) have gained great interest by Distribution Companies (DisCos) as the most common RES. In fact, the connection of enormous RES to existing distribution networks has changed the operation of distribution systems. It also affects the Volt/Var control problem, which is one of the most important schemes in distribution networks. Due to the intermittent characteristics of WFs, distribution systems should be analyzed using probabilistic approaches rather than deterministic ones. Therefore, this paper presents a new algorithm for the multi-objective probabilistic Volt/Var control problem in distribution systems including RES. In this regard, a probabilistic load flow based on Point Estimate Method (PEM) is used to consider the effect of uncertainty in electrical power production of WFs as well as load demands. The objective functions, which are investigated here, are the total cost of power generated by WFs, FCPPs and the grid; the total electrical energy losses and the total emission produced by WFs, FCPPs and DisCos. Moreover, a new optimization algorithm based on Improved Shuffled Frog Leaping Algorithm (ISFLA) is proposed to determine the best operating point for the active and reactive power generated by WFs and FCPPs, reactive power values of capacitors, and transformers’ tap positions for the next day. Using the fuzzy optimization method and max-min operator, DisCos can find solutions for different objective functions, which are optimal from economical, operational and environmental perspectives. Finally, a practical 85-bus distribution test system is used to investigate the feasibility and effectiveness of the proposed method.     

Lipozyme RM IM脂肪酶催化苦瓜籽油和癸酸合成功能性油脂

以苦瓜籽油为原料,利用癸酸在脂肪酶Lipozyme RM IM的催化下进行结构修饰,来降低苦瓜籽油中桐酸的含量。选取底物物质的量的比、加酶量、反应温度、反应时间为影响因素,采用响应面分析法进行反应条件优化,得最佳反应条件为底物物质的量的比(苦瓜籽油:癸酸)=1:4、加酶量(占底物质量的质量分数)12.5%、反应温度60℃、反应时间14.8h。在此最优反应条件下得到的新油脂中癸酸含量为47.12%,同时桐酸含量由反应前苦瓜籽油中的56.17%降为25.46%。     

苦瓜抗氧化活性成分的研究

用不同溶剂抽提苦瓜中抗氧化物质,按一定比例添加到食用油脂(猪油)中,采用烘箱法高温诱导猪油发生过氧化反应,测定其过氧化值作为评价抗氧化性能的依据.实验结果表明:40%乙醇提取物抗氧化效果显著,当在猪油中添加0.1g/50g的40%乙醇提取物时抗氧化作用最佳.40%乙醇提取液经显色的反应初步判断其抗氧化有效成分为酚类、黄酮类物质,且含量分别为0.2015g/500g鲜样和0.0421g/500g鲜样.     

药食两用植物(Ⅱ)-苦瓜的药理作用研究概况

苦瓜含有三萜、甾体类、生物碱、蛋白、有机酸及糖类等多种活性化学成分，具有降血糖、抗肿瘤、抗病毒、抑菌等多种药理活性。本文系统地回顾了近30年来苦瓜药理作用的研究概况，着重介绍了国内外对苦瓜中三萜、甾体及多肽类成分的降血糖、抗肿瘤、抗病毒，抗生育等药理作用的研究进展。     

癞葡萄降糖活性成分的提取及其降糖活性的研究

对癞葡萄中水溶性降糖活性成分的提取进行了研究.以水作为溶剂提取癞葡萄的降糖活性成分,通过10kdal的超滤膜将水提物分为二个组分,并对这两个组分分别进行了降糖活性动物实验.结果表明,大、小分子组分均有一定降糖效果,但相对分子量大于10kdal的组分降糖效果不显著;相对分子量小于10kdal的组分降糖活性显著,起着主要的降糖作用.     

低糖苦瓜果脯的加工工艺

以苦瓜为原料,对影响苦瓜果脯品质的烫漂、护色、温度、渗糖等关键工艺进行研究。结果表明:苦瓜最佳切分厚度为0.7 cm～0.8 cm;烫漂时间为3 min;烫漂温度为90℃。最佳护色和硬化工艺配方为:氯化钙0.5%、亚硫酸氢钠0.5%、氯化钠0.2%、醋酸锌0.3%。最佳渗糖工艺为:CMC浓度为2.0%、β-环状糊精的添加量3%、浸泡液浓度梯度为30%-40%-50%、每次冷浸时间8 h。制成的低糖苦瓜果脯风味好、色泽自然。     

苦瓜总皂苷稳定性研究

采用香草醛-高氯酸比色法测定苦瓜总皂苷含量,考察苦瓜总皂苷在不同条件下的稳定性,对开发苦瓜总皂苷保健食品具有一定的参考价值.实验以性状、熔点、吸湿性、皂苷含量为考察指标,分别考察了高温、高湿、紫外线照射、不同pH值条件下对苦瓜总皂苷含量的影响.结果表明,苦瓜总皂苷在50℃以下,pH6.0～9.0的干燥密闭条件下比较稳定,且紫外线照射对苦瓜总皂苷含量无影响.因此,开发苦瓜总皂苷保健食品具有可行性.