电力市场下基于会计学原理的输电费计算方法比较

电力市场环境下，对使用输电网的用户按照使用影响程度计算输电费用是被广泛接受的计算原则。介绍、分析、比较了基于会计学原理的计费方法（即邮票法、合同路径法、分布因子及潮流追踪法等）。从理论上分析和比较了潮流追踪法中的Bialek’s潮流追踪法和费用流法．并以5节点系统，采用不同方法向发电方计算输电费。算例结果表明：费用流法计算简洁、中间步骤少、累计误差小，是计算输电费简单有效的方法。     

基于DSP的变压器保护装置

介绍了一种基于DSP的新型变压器保护装置,论述了该装置的特点及其原理,然后从软硬件两方面阐述了该装置的工作过程.试验和运行证明,本装置具有良好的工作性能和实用价值,已投入实际工程应用.     

PZT capacitors using IrO2 electrode by RF magnetron sputtering

Abstract

RF magnetron sputtered Pb(Zr_x, Ti_1-x)O₃ [PZT] films were prepared on IrO₂/SiO₂/Si and Pt/IrO₂/SiO₂/Si substrates using the ceramic PZT target with Pb_1.1(Zr_0.52Ti_0.48)O₃ composition. In order to obtain single perovskite phase, PZT film was sputtered at room temperature under Ar plasma and followed by high temperature annealing under oxygen atmosphere. In case of Pt/PZT/IrO₂ capacitor, Δ P (=P*-P∧) was decreased with oxygen annealing temperature. However, it was increased in Pt/PZT/Pt/IrO₂ capacitor. Leakage current density of Pt/PZT/Pt/IrO₂ capacitor, which was used for improving leakage characteristics, was about 10^-2A/cm^?2 order lower than that of Pt/PZT/IrO₂ capacitor. Leakage current density of Pt/PZT/Pt/IrO₂ capacitor annealed at 700°C was 6.6x10^-6A/cm². From the fatigue test, Pt/PZT/IrO₂ capacitor annealed at 650°C and Pt/PZT/Pt/IrO₂ capacitor annealed at 700°C showed 3% and 12% degradation of Δ P after 5×10¹⁰ fatigue cycles, respectively.     

Characterization and control of microcontamination for advanced technology nodes and 300-mm wafer processing: overview and challenges

Advanced process technologies have been introducing many unseen problems on process yield and device reliability. Microcontamination, which enables defects causing electric faults, has also been hard to understand, detect, and control. In this paper, the requirements and methodologies for contamination control in advanced technologies such as at the 90-nm processing technology node and immersion lithography using 300-mm wafer processing were addressed. Combining techniques of vapor phase decomposition (VPD) and wafer outgassing system (WOS) for characterizing the very low levels of surface metallic and organic contaminants on 300-mm wafers makes a front-end process capable of realizing and deploying the necessary controls. Applying liquid chromatography-mass spectrometry (LC-MS) in the identification of contaminants of immersion fluids is a new experience for 193-nm lithography technology. Furthermore, the wafer-environment contamination controls, such as airborne molecular contaminants (AMCs), process critical material assurance and point-of-use quality are reviewed in the paper. This paper concludes by discussing the challenges for characterization and control of microcontamination in future manufacturing technologies.     

Image matching using enclosed region detector

Affine-invariant region detection is the basic technique for visual matching and has been widely applied in many areas. In this paper, we propose a simple yet effective method to detect the affine-invariant regions from gray image, which is called enclosed region. The enclosed region is detected based on the observation that one physical object is enclosed by the same region before and after affine transformation. The proposed method is a three-step method. Firstly, we segment the initial regions by using thresholds on the image. Secondly, external enclosing region (EER) and internal enclosed region (IER) are defined for each initial region, and we select the enclosed regions from the initial regions through applying histogram constraints on EER and IER. Thirdly, the largely overlapping regions are removed. Experiments on typical images exhibit the robustness of the proposed enclosed region detector. Extensively quantitative evaluation and comparison demonstrate that the proposed method outperforms state-of-the-art methods.     

电网电压矢量定向的三相异步电机同步切换控制策略

鉴于大容量三相交流异步电机在进行变频-工频切换瞬间存在较大的电网冲击电流,提出一种基于电网电压矢量定向的同步切换控制策略,并采用电力电子开关与交流接触器并联的电路拓扑实现电机变频-工频的同步切换。该控制策略在电网电压同步坐标系下检测到变频器输出线电压空间矢量的相位为30°电角度时触发电力电子开关和交流接触器进行同步切换。实验结果表明该控制策略可精确捕获电机同步切换的最佳时刻实现零相位误差切换,电力电子开关可大幅缩短切换时间,提高了切换控制精度和系统对不同电机及负载的适应性。     

110kV电压互感器计量二次电压接地线故障分析

电压互感器二次电压降是造成电能计量误差的重要因素之一,文章针对110kV电压互感器计量二次电压接地线故障对电能计量的影响进行分析,提出改进措施及方法,为实际工作提供有效参考。     

关口电能表PT二次压降的改造

电能表ＰＴ二次压降影响电能计量的准确性,据调查,黑龙江省１９９７年其合格率仅为１２％,为贯彻实施厂网分开、竞价上网的政策,改造迫在眉睫。论述电能表ＰＴ二次压降的改造方法,采用电能表专用电压回路的措施,可以达到规程的要求,并在１９９８年黑龙江省关口电能自动计量系统工程中对发电厂部分予以实施,获得了巨大的经济效益。     

地区电网调度自动化系统的标准化与规范化建设

阐述了地区网调度自动化系统的标准化、规范化建设的重要性,着重分析和讨论了建设中的关键问题：远动规约标准化、调度自动化系统软件标准化、SCADA／EMS系统质量检验标准化、调度管理信息系统规范化。并提出了地区电网调度自动化系统标准化、规范化建设的策略和发展方向。     

Design and implementation of a contact‐less power charger for robot applications

In this paper, a contact‐less power charger for robot applications is studied and developed. Contact‐less charging can be achieved by a separable transformer design. The transformer primary core is in the charger unit, and the secondary core is in the robots. The transformer air‐gap is equal to the distance between these two parts. By theoretical analysis, software simulations, and circuit implementation, the relationship among the transformer's coupling coefficient, the core geometry, and gap are formulated. In addition, a high‐efficiency circuit topology for the studied contact‐less charger is fulfilled. It is anticipated that the research results of this paper can contribute to the development of the contact‐less charging techniques for robot systems. Copyright © 2012 John Wiley & Sons, Ltd.