关于"SG186"工程的几点思考

从企业信息化的角度,对“SG186”工程进行了剖析。结合工作实际提出了公司信息化应用系统总体架构模型和一体化平台的模型;通过比较市场上企业门户产品的优缺点,建议公司门户采用企业应用门户（EAP）：针对“SG186”工程实施过程的几个关键问题提出了解决方案。     

2002～2003年国家电网公司系统变压器类设备事故统计与分析(一)

章主要对国家电网公司系统110kV及以上电压等级变压器类设备的事故进行统计分析，着重反映这些设备在运行中的质量情况及其发生的问题，以此作为质量信息反馈和编制设备技术标准、运行管理规范、检修作业指导书、技术监督规定以及反事故措施的重要依据。     

LPC2142的低功耗有源RFID手持机设计

提出一种可以显著降低有源RFID手持机功耗的流程,并采用微处理器LPC2142为核心,结合MAX1551、LTC3530、LTC3525-5 V、CH452A、nRF24L01等外围器件,完成具有有源RFID标签读写功能的低功耗手持机的设计.该手持机在开阔场地的有效阅读距离可以达到80 m左右,其电池的待机时间为1O天...     

高精度连续可调高压开关电源的设计

提出了一种高精度连续可调的高压开关电源设计方案。电源采用基于SG3525的恒频脉宽调制技术,通过单片机控制可控增益放大器实现输出电压的连续调整,该电源具有高电压输出精度高、连续可调、功耗小等特点。实验结果表明,当该电源输出电压由1kV-25kV可调输出时,输出电压误差最大为1．6％。     

PSB-VVER simulation of Kozloduy NPP “loss of feed water transient”

This paper provides a comparison between the PSB test facility experimental results obtained during the simulation of loss of feed water transient (LOFW) and the calculation results received by INRNE computer model of the same test facility. Integral thermal-hydraulic PSB-VVER test facility located at Electrogorsk Research and Engineering Center on NPPs Safety (EREC) was put in operation in 1998. The structure of the test facility allows experimental studies under steady state, transient and accident conditions.RELAP5/MOD3.2 computer code has been used to simulate the loss of feed water transient in a PSB-VVER model. This model was developed at the Institute for Nuclear Research and Nuclear Energy for simulation of loss of feed water transient.The objective of the experiment “loss of feed water”, which has been performed at PSB-VVER test facility is simulation of Kozloduy NPP LOFW transient. One of the main requirements to the experiment scenario has been to reproduce all main events and phenomena that occurred in Kozloduy NPP during the LOFW transient. Analyzing the PSB-VVER test with a RELAP5/MOD3.2 computer code as a standard problem allows investigating the phenomena included in the VVER code validation matrix as “integral system effects” and ”natural circulation“. For assessment of the RELAP5 capability to predict the “Integral system effect” phenomenon the following RELAP5 quantities are compared with external trends: the primary pressure and the hot and cold leg temperatures. In order to assess the RELAP5 capability to predict the “Natural circulation” phenomenon the hot and cold leg temperatures behavior have been investigated.This report was possible through the participation of leading specialists from Kozloduy NPP and with the support of Argonne National Laboratory (ANL), under the International Nuclear Safety Program (INSP) of the United States Department of Energy.     

Algebraic approach for the diagnosis of turbine cycles in nuclear power plants

According to plant operating staff's practical needs, authors proposed a diagnosis model to identify the performance degradation of steam turbine cycles in nuclear power plants (NPPs). The essential idea of this study is how to identify the intrinsically degraded component which causes electric loss. Authors found that there were not so many turbine cycle diagnosis applications in NPPs currently because of technical, financial, or social characteristics of the plant. So a great part of the diagnosis has been dependent on operating staff's experience and knowledge. However as economic competition becomes severe, the efficiency staffs is asking for reliable and practical advisory tools. For the solution of these shortcomings, authors proposed a simple and intuitive diagnosis concept based on the superposition rule of degradation phenomena, which can be derived by simple algebra and correlation analysis. Though the superposition rule is not so significant statistically, almost all of the performance indices under normal operation are fairly compatible with this model. Authors developed a prototype model of quantitative root-cause diagnosis and validated the background theory using the simulated data. The turbine cycle advisory system using this model was applied to Gori NPP units 3&4.     

基于System Generator的SVPWM算法设计及实现

根据空间矢量脉宽调制(SVPWM)原理,提出一种基于人工神经网络(ANN)的SVPWM新算法。该网络系统结构分布化,利用神经网络的并行处理能力,将复杂的计算任务分散化,缩短了计算时间。在新的设计环境SystemGenerator/Simulink下建立了SVPWM的算法模型,并进行了硬件仿真,将模型下载到FP-GA芯片,产生了SVPWM波形,实验结果表明了该方法的有效性和可行性。     

基于P89LPC933的大功率智能充电器的设计

设计了一种基于P89LPC933单片机控制的大功率智能充电器,提出了四阶段充电控制方法。结合主电路和MCU控制电路详细地阐述了其控制策略以及充电器的硬件设计和软件设计。与市场上典型的充电器做了横向比较与总结。     

Learning Behaviors of Stochastic Gradient Radial Basis Function Network Algorithms for Odor Sensing Systems

Learning behaviors of a radial basis function network (RBFN) using a singular value decomposition (SVD) and stochastic gradient (SG) algorithm, together named RBF‐SVD‐SG, for odor sensing systems are analyzed, and a fast training method is proposed. RBF input data is from a conducting polymer sensor array. It is revealed in this paper that the SG algorithm for the fine‐tuning of centers and widths still shows ill‐behaving learning results when a sufficiently small convergence coefficient is not used. Since the tuning of centers in RBFN plays a dominant role in the performance of RBFN odor sensing systems, our analysis is focused on the center‐gradient variance of the RBFN‐SVD‐SG algorithm. We found analytically that the steady‐state weight fluctuation and large values of a convergence coefficient can lead to an increase in variance of the center‐gradient estimate. Based on this analysis, we propose to use the least mean square algorithm instead of SVD in adjusting the weight for stable steady‐state weight behavior. Experimental results of the proposed algorithm have shown faster learning speed and better classification performance.     

An evolution of molten core cooling strategies

Fundamental mechanisms behind the molten core cooling strategies are revisited to provide an insight for a proper implementation of severe accident management guideline (SAMG) and a development of an engineered safety feature. From the results of a qualitative evaluation and a quantitative plant analysis, weak points of the current severe accident management guideline for an operating plant are identified and a revision of the molten core cooling strategies is proposed. In addition, technical issues for various kinds of core catcher concepts are discussed.