Current forging technology for integrated type steel forgings for nuclear steam supply system components

This brief review concerns the trend in using large size, integrated type steel forgings for nuclear steam supply system components as intended for easier in-service inspection (ISI).To achieve this trend, unique forging techniques have been developed.The forging techniques corresponding to each integrated type steel forging product together with a brief explanation of the development of forging facilities as well as a future aspects are introduced.     

Expected role of nuclear science and technology to support the sustainable supply of energy in Indonesia

Energy resources are available in Indonesia but small per capita. The increase of oil price and its reserve depletion rate dictates to decrease the oil consumption. Therefore, it is imperative to increase the shares of other fossils as well as the new and renewable sources of energy in various energy sectors substituting the oil. The introduction of nuclear power plant becomes more indispensable, although the share is to be small but significantly important for electric generation in Java–Madura–Bali grid. Nuclear technology can have also important role enabling the increase of the shares of renewable, e.g. geothermal, hydro and bio-fuels as well as fossil energies to meet more sustainable energy mix sufficing the energy demand to attain intended economic and population growths while maintaining the environment. The first introduced nuclear power plant is to be the proven ones, but the innovative nuclear energy systems being developed by various countries will eventually also be partially employed to further improve the sustainability. The nuclear science and technology are to be symbiotic and synergistic to other sources of energy to enhance the sustainable supply of energy.     

Economics of nuclear electricity and inter-fuel competition

The costs of generating base-load electricity are compared on a unified costing basis assuming the plants' size for the different fuel alternatives—nuclear, coal, gas, biomass and peat—to vary according to the infrastructure requirements. Fuel costs are assumed to reflect the market values in Europe to as realistic an extent as possible. Recognizing that there may be a substantial local or regional differences, it is concluded that nuclear electricity generally enjoys a narrow competitive edge, which can become more significant if fossil fuel prices escalate or if energy and carbon taxes are introduced.     

Sustainability of fission energy in future equilibrium society

The system of a fast reactor fed with natural uranium is discussed as a future sustainable energy producing system, concentrating especially on the waste problem. The following conclusions have been derived:

1. 1.|When the reprocessing with very small leakage rate can be employed, the conventional fast reactor has a potential to confine all actinides in the core.

2. 2.|The total toxicity of LLFPs is smaller but comparable to the toxicity of burned natural uranium with its daughters.

3. 3.|When the isotope separation is employed for each LLFP, whole LLFPs can be incinerated using the conventional fast reactor system with natural uranium.

4. 4.|When only the element separation is employed, the incineration of ¹⁰⁷Pd should be given up even by employing several design changes, but its toxicity is only 0.0002 of the incinerated uranium toxicity.

On possibility of direct electroionizing conversion of nuclear energy to electricity

The objective of the present article is theoretical investigation of possibility of direct conversion of the nuclear energy to electricity without all intermediate stages: the thermal and the mechanical. The principle of this method (so-called ‘electroionizing’) is ionization of rare gas atoms with fission fragments and separation of generated positive and negative ions with the external electric field. Under certain conditions, when so-called the Debye’s screening of charged particles within the produced plasma takes place, the recombination among these particles is insignificant. It is discovered that because of the absence of Carno’s limit on the efficiency of conversion, the performance coefficient may be 40–50% irrespective of temperature. The conditions of serviceability of the present method are definited.     

晶闸管电源调节器设计

给出了晶闸管整流环节的传递函数,利用自动控制原理,设计了晶闸管电源调节器并在HIRFL注入引出电源MI2得到了应用。     

Sustainability by combining nuclear,fossil, and renewable energy sources

The energy industries face two sustainability challenges: the need to avoid climate change and the need to replace traditional crude oil as the basis of our transport system. Radical changes in our energy system will be required to meet these challenges. These challenges may require tight coupling of different energy sources (nuclear, fossil, and renewable) to produce liquid fuels for transportation, match electricity production to electricity demand, and meet other energy needs. This implies a paradigm shift in which different energy sources are integrated together, rather than being considered separate entities that compete. Several examples of combined-energy systems are described. High-temperature nuclear heat may increase worldwide light crude oil resources by an order of magnitude while reducing greenhouse gas releases from the production of liquid fossil fuels. Nuclear–biomass liquid-fuels production systems could potentially meet world needs for liquid transport fuels. Nuclear–hydrogen peak power systems may enable renewable electricity sources to meet much of the world's electric demand by providing electricity when the wind does not blow and the sun does not shine.     

New-generation space thermionic nuclear power systems with out-of-core electricity generating systems

The basic problems of the development of long service life thermionic nuclear power systems for space applications for supplying power to transport power modules, intended for placing spacecraft in a geostationary orbit using electrorocket motors and for providing prolonged operation of onboard systems for up to 10–15 years, are examined. Concepts for power systems with multi- and single-element thermionic low-temperature energy-conversion systems, which are placed outside the reactor core and in which heat is delivered to the emitters using molybdenum-lithium heat pipes at 1600–1670 K, are discussed as an example. Computational results are presented for the electro- and thermophysical characteristics of electricity generating systems and power systems with different variants of the design-technological solutions, including the possibility of increasing the service life by reserving a part of the thermionic electrical power. The mass/size characteristics of the power systems with basic variants of the systems are obtained and recommendations based on research and development work are made, 8 figures, 8 references. Translated from Atomnaya énergiya, Vol. 89, No. 1, pp. 22–34, July, 2000.     

4MV静电正离子加速器辐射监测系统

介绍由主控计算机和多个探测通道组成的辐射监测系统,可以对多种辐射的能量、强度、剂量率、剂量及剂量当量进行监测.该系统虽然是为4MV静电正离子加速器辐射监测设计制作的,但同样适用于类似条件的其他场所的辐射监测.     

上海同步辐射装置电源控制系统

上海同步辐射装置电源控制系统是基于EPICS系统开发运行的分布式控制系统。系统中~65 K实时数据库记录分布运行于27个VME总线的IOC控制器中,实现了对600多台各类磁铁电源的访问控制。本文介绍了电源控制系统基于Ethernet的层次式结构与工作原理,分别描述了针对PSI与SINAP电源控制器的控制解决方案,同时介绍了系统的硬件设备、IOC和控制台软件及系统中采用的通讯技术。     

多通道AC电源控制器的研制

简要介绍多通道AC电源控制器。该控制器是一个多路程控开关设备,它由计算机进行控制。该仪器是为一个220V交流电源供电系统自动控制与监视系统设计研制的,是该系统的关键前端设备。     

Reactors for low-temperature nuclear heat supply

Nuclear sources are not only covering more than 16% of today's electricity production but can also supply heat for district heating and industrial needs. Thus the nuclear generated heat substitutes for fossil fuels with good efficiency and economy and with much higher environmental cleanliness. Low-temperature nuclear heat is gained in several countries from the reactors of nuclear power plants by co-generation of heat and electricity which is already a proven technology. Specialized nuclear heating plants are in an early stage of development. The paper gives an overview of the situation worldwide and shows also specific common safety characteristics of these reactors.     

质子治疗装置脉冲电源研制

上海质子治疗装置项目中质子注入系统凸轨磁铁需要脉冲电源励磁,要求两台电源脉冲峰值幅度可调和波形一致,且运行可靠。本文介绍了凸轨磁铁脉冲电源的设计和测试。脉冲电源电路采用LC串联谐振作为脉冲成形发生电路,电路设计可调电感用于调整波形脉宽。晶闸管为电流开关,快恢复二极管串联晶闸管弥补大功率晶闸管的关断延迟和下冲,并增加饱和电抗器抑制励磁电流反向电流尖峰。测试结果表明,当励磁电流峰值为3 732 A时,励磁电流触发抖动小于±25 ns,励磁电流峰值重复稳定度小于0.1%,反向电流尖峰下降为峰值电流的3.75%,快恢复二极管和饱和电感器对抑制励磁电流反冲的效果明显,满足了设计要求。     

Model-predictive control of power supply for particle accelerators

In this paper, model-predictive control （MPC） is proposed for controlling power source of accelerators. The system state equa.tion is employed as the predictive model. With MPC, the difference between possible output and the ideal output is forecasted and decreased, so that the system can trace the ideal trail as closely and quickly as possible. The results of simulations and experiments show that this method can reduce influence of low frequency noise.