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91.
本文采用PWM逆变技术设计了一个备用电源,并应用到防火卷帘控制器中。当火灾发生时,该系统可保证防火卷帘门的正常运行,对人员安全疏散、控制火势蔓延、减少火灾损失起到重要作用。 相似文献
92.
陕西省电力公司企业资源管理项目组 《西北电力技术》2007,(5)
介绍了国家电网公司“SG186”工程统一咨询的特点和主要结论。根据国家电网公司的现状评估,提出了业务应用中存在的问题及改进方向,阐述了项目管理改进的主要原则,明确了国家电网公司“SG186”工程与陕西省电力公司ERP系统建设的关系。 相似文献
93.
介绍了一种基于SG3525的单极性SPWM控制电路,其中包括取样电路、基准电路、SPWM脉冲形成电路、编码延时驱动电路。该电路简单,容易实现,可作为实现单极性DC/AC电源SPWM控制器的参考。 相似文献
94.
根据KA3525的应用特点,设计了一种基于该电流型PWM控制芯片和单片机控制实现输出电压可调的稳压电源电路.本文主要介绍了它的主电路、调控电路以及调控电路所包含的控制电路、稳压电路和保护电路,并介绍了它们的实现原理与方法. 相似文献
95.
96.
M.P. Pavlova P.P. Groudev A.E. Stefanova R.V. Gencheva 《Nuclear Engineering and Design》2006,236(3):322-331
This paper provides a comparison between the real plant data obtained by Unit 6 of Kozloduy nuclear power plant (NPP) during the loss-of-feed water (LOFW) transient and the calculation results received by RELAP5/MOD3.2 computer model of the same NPP unit.RELAP5/MOD3.2 computer model of the VVER-1000 has been developed at the Institute for Nuclear Research and Nuclear Energy-Bulgarian Academy of Sciences (INRNE-BAS) based on Unit 6 of Kozloduy NPP. This model has been used for simulation the behavior of the real VVER-1000 NPP during the LOFW transient. Several calculations have been provided to describe how the different boundary conditions reflect on the prediction of real plant parameters.This paper discusses the results of the thermal–hydraulic sensitivity calculations of loss-of-feed water transient for VVER-1000 reactor design. The report also contains a brief summary of the main NPP systems included in the RELAP5 VVER model and the LOFW transient sequences.This report was possible through the participation of leading specialists from Kozloduy NPP and with the assistance of Argonne National Laboratory (ANL) for the United States Department of Energy (US DOE), International Nuclear Safety Program (INSP). 相似文献
97.
The advanced PWR fuel for the OPR1000s in Korea, PLUS7, has been developed to enhance thermal performance, high burnup capability and fuel reliability against grid-to-rod fretting wear and debris. The outstanding design features of PLUS7 include mixing vane mid-grids for increasing thermal performance and minimizing vibration-induced fretting wear, optimized fuel dimensions and advanced zirconium alloys for high burnup capability of 72,000 MWD/MTU, and an optimized fuel rod diameter for reducing pressure drop and improving neutron economy. The fuel assembly and its components performances have been verified through a wide spectrum of mechanical, thermal hydraulic, vibration and fretting wear tests. Based on the verification test results and the evaluations with the help of the KNF design code system, it is found that the PLUS7 fuel will maintain its integrity up to the envisaged burnup of 72,000 MWD/MTU. In addition, the PLUS7 fuel performances were evaluated to be considerably improved in comparison with the current fuel used in the OPR1000s. 相似文献
98.
99.
This paper aims to explore the possibility of synchronous generator (SG) based wind energy generation system feeding an isolated load using a latest power transmission technology i.e. variable frequency transformer (VFT). The proposed configuration does not employ any power electronics based interface as in conventional SG based stand-alone wind energy conversion systems (SWECS). For analysis, the simulation models of proposed configuration as well as conventional configuration have been developed under MATLAB-Simulink environment. A series of studies on power fed from the SG to the different loads at various SG input speeds has been carried out with the developed models. Further to analyze the effectiveness of the proposed method; the efficiency, total harmonic distortion (THD) of output voltage and THD of output current of the proposed method have been compared with those of the conventional method. From obtained results, it is observed that the proposed method is simple and does not produce harmonics. Moreover to validate the proposed scheme, an experimental analysis has been carried out. Further, the cost analysis of both systems has also been carried out. From the cost analysis, it is observed that the proposed system is cheaper than the conventional system. 相似文献
100.