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31.
Yu. S. Gorbunov A. G. Ageev R. V. Vasil’eva B. M. Korol’kov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(3):166-170
A system for the direct measurement of steam flow in steam lines after a steam generator, which utilizes a special design
of pneumometric tubes and a computing unit that accounts for variation in steam pressure, has been developed to improve the
quality of water-level regulation in the steam generators of VVéR-1000 power-generating units in the stationary and transitional
modes. The advantage of the pneumometric tubes consists in their structural simplicity, high erosion resistance, and absence
of irrevocable losses during measurement of steam flow. A similar measurement system is used at foreign NPP. The measurement
system in question has been placed in experimental service at the No. 3 unit of the Balakovo NPP, and has demonstrated its
worthiness. This measurement system can also be used to determine steam flow in the steam lines of NPP units with VVéR-1000
and VVéR-440 reactors, and PBMK-1000 power-generating units.
__________
Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 23–26. 相似文献
32.
Masahide Hojo Yasunori Mitani Toshifumi Ise Kiichiro Tsuji 《Electrical Engineering in Japan》2002,138(3):43-51
The advancement of power electronics technologies has significantly developed the power system stabilizing controllers. Quantitative as well as qualitative evaluation of their effectiveness in power systems is a matter of great importance for the feasibility investigation of these apparatus. In this paper, the possible control region of FACTS controllers with series and/or shunt configuration in a single machine to infinite bus system is formulated in the powerangle curve with a set of algebraic equations. The effectiveness of TCPST (Thyristor‐Controlled Phase Shifting Transformer), SSSC (Static Synchronous Series Compensator), and TCSC (Thyristor‐Controlled Series Compensator) for the improvement of the transient stability is evaluated quantitatively as a numerical example. The correctness of the proposed method has been confirmed by analysis based on the electromagnetic transients simulation with a detailed system model. © 2001 Scripta Technica, Electr Eng Jpn, 138(3): 43–51, 2002 相似文献
33.
34.
Cruselles Ernesto J. Soriano Miguel Melús José Luis 《Wireless Personal Communications》1998,7(1):69-88
The prime characteristic of spread spectrum modulated signals is that their bandwidth is greater than the information rate. In this way a redundancy is introduced that allows the severe levels of inteference inherent in the transmission of digital information over radio and satellite links to be overcome. Current spread spectrum applications are primarily in military communications; nevertheless, there is growing interest in this technique for third generation mobile radio networks (UMTS, FPLTS, etc.) with open discussion regarding the practicality of using a multiple access system based on spread spectrum techniques (CDMA). However, in order to support as many users in the same bandwidth as other multiple access techniques such as TDMA or FDMA, it is important how to generate large families of sequences that present low cross-correlation. The aim of this paper is to describe a spreading codes generator that can produce a large number of PN sequences with good properties of auto- and cross-correlation. Moreover, the codes generated shows high unpredictability and good statistical behaviour. This also allows the implementation of some features that are common on military networks such as message privacy (increasingly important in commercial networks) without additional cost. The structure presented shows itself to be advantageous for high speed generation of codes at a low cost, low power consumption (allowing longer life for batteries), small size and simplicity of implementation, essential ingredients for commercial equipment. Another attractive feature is its structural parallelism, useful in VLSI implementations. All of these features render it potentially suitable for the implementation of channel bandwidth sharing systems in future wireless personal communications networks. 相似文献
35.
The durability of a cold wall MHD generator consisting of metal electrodes and alumina-coated peg insulators was experimentally examined in the oil-fired MHD condition with the additive of SO2 corresponding to S = 0.54 wt%. The structure of the electrode wall and various anode and cathode materials were tested, with particular reference to developing long-life electrodes. It was clarified that Pt, SHOMAC (28.8 Cr−1.9 Mo) and SUS-304 as anodes and W---Cu (70 W−30 Cu) and WC---Ag (60 WC−40 Ag) alloys as cathodes were promising for durability and that the structure of an anode divided into two elements connected to each other with an SnO2 resistor was very useful for uniformity of the anode corrosion pattern and the inter-anode voltages. It is reasonable to expect, from the test results, that the lifetime of a cold wall MHD generator in an oil-fired commercial plant will be over 4000 h, and therefore, a foundation for its commercial use has been established. 相似文献
36.
正向设计了一种适合于听觉神经刺激的可编程双相恒流脉冲发生器,它可根据耳聋患者的要求和不同的语音信号,控制刺激电流脉冲的幅度和宽度,以及脉冲之间的间隙。本文阐述了电路的设计要求和方法,并给出了实验结果。采用标准3μmp阱CMOS工艺,在上海贝岭微电子制造有限公司流片。目前已成功地用于多道人工电子耳蜗接收刺激器中。 相似文献
37.
大中型风力发电机组可靠性研究 总被引:6,自引:2,他引:4
研究了大中型风力发电机组的可靠性,讨论了可靠性指标的分配,可靠性设计的四个重要方面、可靠性试验计算机模拟。 相似文献
38.
国产核电厂蒸汽发生器下封头群孔接管区具有应力分布复杂、焊接施工条件差的特点。为考核其承受循环载荷的能力,设计制造了与实物相似的模拟试验装置,根据核电厂运行寿命期内的载荷特点,确定了模拟试验装置的试验载荷与试验循环数。循环加载试验的结果表明,蒸汽发生器下封头群孔接管区承受循环载荷的能力在寿命期内是符合要求的。 相似文献
39.
简要介绍了蒸汽发生器水位控制系统的运行方式和试验方法。试验项目包括旁通阀控制试验、主给水阀控制试验和旁通阀与主给水阀的切换试验。文中给出了试验结果,即在液位扰动和核动率扰动时,蒸汽发生器液位的变化过程。经过两个月的运行和瞬态试验,证明蒸汽发生器水位控制系统满足设计要求。 相似文献
40.
本文较系统、通俗地介绍了模拟视频特技切换台的矩阵输入、混合/效果放大器(M/E)、下游键、系统控制和同步发生器等电路单元,介绍了特技切换台的切换、混合、扫变、键控的基本原理和功能。 相似文献