双三相异步电机电流预测控制算法

针对一种半对称式双三相异步电机,提出两种电流预测控制算法。一种为基本算法,另一种为在基本算法的基础上通过引入合理近似而实现的模块化算法。相对而言,后者更为简洁,且易于在其他一些结构更为复杂的多相电机中进行推广。此外,针对离散控制的延时对上述两种算法带来的稳定性问题进行分析,并给出改进方案。实验结果表明,两种电流预测控制算法均能实现良好的电流控制效果,同时该文针对稳定性问题的改进方法也是有效的。     

高温质子交换膜燃料电池堆的建模与仿真

高温质子交换膜燃料电池相较于传统质子交换膜燃料电池具有更快的电化学动力性,简易的水热管理以及较强的耐CO能力等优点,因此已成为燃料电池研究工作的新热点。建立了高温质子交换膜燃料电池堆的模型,研究单电池数量、电流密度、阳极进气湿度等因素对电池堆性能的影响。研究表明,Z型结构电池堆内阳极气体质量流量分布比较一致,阴极气体质量流量分布呈中间低,两侧高的趋势。单电池数量、电流密度的增大会引起气体分布不均匀性的增强,进而使电池堆电压不均匀性增大;阳极进气湿度的变化主要影响电池欧姆损失。     

硫酸尾气玻璃钢烟囱内筒设计

以某冶炼厂硫酸尾气烟囱设计为例,将具有耐腐蚀性、耐高温性的玻璃钢材质应用于烟囱内筒的制作上。详细阐述了玻璃钢烟囱内筒的选材、结构设计以及施工安装注意事项等,并提出了玻璃钢烟囱内筒应用中需解决的问题。     

浅谈3012H型自动烟尘(气)测试仪的使用和维护管理

阐述了3012H型自动烟尘(气)测试仪的主要工作原理;结合自身工作实际,总结了3012H型自动烟尘(气)测试仪的日常使用和维护操作,着重介绍了相关附件在使用和维护过程中需要注意的问题。     

基于89C52RC控制的导爆管雷管延期体测时装置

介绍了一种能够降低延期导爆管雷管检验成本、提高检验人员安全性的延期体测时装置。该装置利用89C52RC单片机做检测和控制的核心部件;采用光电二极管,并利用双运算放大器LM358将信号放大;放大后的信号通过信号线传递给89C52RC单片机;从而控制单片机计时器的启动和停止;并在数码管上记录所测延期体的延期时间。     

One-step synthesis of poly(2-oxazoline)-based amphiphilic block copolymers using a dual initiator for RAFT polymerization and CROP

A range of poly(2-oxazoline) (POx)-based amphiphilic block copolymers were synthesized using 4-cyano-4-(dodecylthiocarbonothioylthio)pentyl-4-methylbenzenesulfonate (CDPS) as a dual initiator for reversible addition-fragmentation chain transfer (RAFT) polymerization and cationic ring-opening polymerization (CROP) in a one-step procedure. Methyl (meth)acrylate, butyl (meth)acrylate, tert-butyl (meth)acrylate, and N-isopropylacrylamide were polymerized for the hydrophobic block, and 2-methyl-2-oxazoline and 2-ethyl-2-oxazoline were used as the hydrophilic block. RAFT polymerization and CROP proceeded independently in a controlled manner and resulted in amphiphilic block copolymers with a narrow molecular weight distribution. CDPS was found to be a useful dual initiator for the one-step synthesis of POx-based amphiphilic block copolymers via a combination of RAFT polymerization and CROP.     

Membrane performance comparison in a proton exchange membrane fuel cell (PEMFC) stack

A 5-cell proton exchange membrane fuel cell (PEMFC) stack with different types of membrane electrode assemblies (MEAs) was tested to compare their performances and electrochemical characteristics. The experimental data were obtained with a stack of 5 cells and active area of 125 cm². The stack consisted of different Nafion^® and hydrocarbon membranes with the same types of electrocatalyst. The membranes were installed in different cells and in the same stack. Polarization and voltage measurement data were obtained to compare their performances at different temperatures and anode humidity conditions. Also, impedance spectroscopy data were obtained in similar manner to compare the differences in their resistance.     

Desulfurization matching with coal poly-generation system based on dual gas resources

The coal poly-generation system for the production of alcohol and ether fuels as well as power is one of advanced coal utilization techniques. The team leaded by Professor Xie Kechang is carrying out the research on the poly-generation system to produce the syngas from the combination of gasified and pyrolyzed coal gas (dual gas resources) for the alcohol ether synthesis. Gas desulfurization is one of the key technologies for this system. The desulfurization matching with dual gas resources based poly-generation system for the production of alcohol and ether fuels as well as power is presented according to gas components, sulfur content, sulfur species and desulfurization accuracy in this technology. This matching desulfurization is classified into hot gas desulfurization, normal gas desulfurization, warm gas desulfurization and organic sulfur catalytic conversion. The preparation of H₂S removal sorbents, organic sulfur hydrolysis catalyst and the evaluation of their activities involved in the system were investigated. The H₂S removal efficiencies of the crude and fine desulfurization sorbents prepared for hot gas desulfurization are 90% and 99% at 500 °C in simulating coal gas, and their sulfur capacities are 21.85 wt.% and 24.91 wt.%, respectively. The organic sulfur catalyst shows the high hydrolysis activity, and the hydrolysis conversion of COS is more than that of CS₂ on the same catalyst. The research will provide necessary information for the matching desulfurization technology in the demonstration project on dual gas resources coal poly-generation system.     

烟塔合一技术的应用及对环境影响的分析

介绍了烟塔合一技术在大唐哈尔滨第一热电厂的应用情况,阐述了烟塔合一技术的优势,详细讨论了采用烟塔合一后对烟气的抬升高度、污染物排放以及循环水质的影响,从环境影响角度对烟气的烟囱排放和烟塔合一排放方式进行了比较。     

石灰石石膏湿法脱硫后烟囱“降雨”原因分析及建议

近年来大部分石灰石石膏湿法脱硫装置取消了烟气加热器(GGH),多个电厂出现烟囱"降雨"现象。结合某600 MW机组烟囱"降雨"较为严重的问题,对"降雨"中所含固体物质成分和影响烟囱"降雨"的因素进行了分析,并提出了相应的建议。