Precision supply system of the group of magnetic elements of the Low-Energy Particle Toroidal Accumulator

An individual power supply source is usually used for each group of identical magnetic elements in accelerators of charge particles. We discuss the power supply and control system on the basis of additional current shunts applied for the simultaneous supply of several groups of magnets in the positron storage ring of the Low-Energy Particle Toroidal Accumulator (LEPTA). Data on the use of the shunt of the linear and key converter are given. The option of the device of a power supply system with the transformation of the recuperated energy in the storage battery and supply from it of the precision power supply sources of the LEPTA correcting magnets is considered. A channel of the individual digital transformation of power supply system elements is given which allows one to build, together with a reverse precision converter, effective intellectual balanced power supply systems.     

Storage ring with longitudinal magnetic field LEPTA (Stellatron)

The project of the Low Energy Particle Toroidal Accumulator (LEPTA) is dedicated to the construction of a positron storage ring with electron cooling of positrons circulating in the ring. Such a specific feature of LEPTA automatically enables it to be a generator of positronium (Ps) atoms, which appear in the recombination of positrons with cooling electrons inside the cooling section of the ring. The project has the following goals: particle dynamics in the modified betatron, electron cooling with a circulating beam, positronium generation in flight, positronium physics, and feasibility of antihydrogen generation in flight. All key elements of the ring—the kicker, electron beam injection system, helical quadrupole, septum magnet—have been tested, and the expected design parameters have been achieved for these elements. The construction of LEPTA has been completed, and the circulating electron beam has been achieved. This paper discusses the issues of particle dynamics in such an accelerator, the results of numerical simulation and experimental findings of the research into beam dynamics, measurement of betatron number and beam lifetime.     

LEPTA project: Formation and injection of positron beam

The project of the Low-Energy Particle Toroidal Accumulator (LEPTA) has been developed and is put into operation at the Joint Institute for Nuclear Research (Dubna). The LEPTA facility is a small positron storage ring equipped with an electron cooling system. The project positron energy is 2?C4 keV. The main purpose of the facility is to generate an intense flux of positronium atoms (the bound state of the electron and positron). The LEPTA storage ring was commissioned in September 2004. The positron injector was designed in 2005?C2010, and the beam transport channel was constructed in 2011. The experiments on electron and positron injection from the injector into the accumulator were started in August 2011. The results are reported here.     

Development of the Low Energy Particle Toroidal Accumulator project

The Low Energy Particle Toroidal Accumulator (LEPTA), a positron storage ring with electron cooling, was constructed and put in operation at the Joint Institute for Nuclear Research (Dubna). The storage ring is a generator of directed beams of ortho-positronium (o-Ps) produced upon the recombination of the beam of positrons circulating in the storage ring with a single-pass electron beam. In 2004 the storage ring was put in operation with the circulating electron beam. The source of positrons of the positron injector was tested with a new radioactive source delivered from South Africa. The positron trap was put in operation for electrons. The electron cooling system was tested with a pulsed electron beam. The progress in commissioning LEPTA is described in this paper.     

Computation of Stationary Fields in the 3D Area in the Penning–Malmberg–Surko Trap at the Low Energy Particle Toroidal Accumulator

Computation of stationary and RW fields in the 3D area in the Low Energy Particle Toroidal Accumulator (LEPTA) Penning–Malmberg–Surko trap using the DAISI code and approximation of the RW field are considered.     

Intellectual system for power supply and control of magnetic component groups of particle accelerators from several MW-power sources

It is necessary for the power-consuming magnetic components of channels for beam transport in accelerators of charged particles be supplied with direct current. An individual power source is typically applied for each group of identical components. A variant of the simultaneous supply of several groups of magnets from a single medium-power source using auxiliary current shunts of different types is given by the example of a LEPTA positron storage ring. One version of using this technology with MW-power sources for a phasotron accelerator is developed. The efficiency of putting this technology into practice with the application of start-stop regimes for the phasotron is estimated.     

A positron injector for the LEPTA accumulator

An injector of monochromatic positrons for the low-energy positron accumulator (LEPTA) is being tested at the Joint Institute for Nuclear Research. The source of positrons is the radioactive source ²²Na. At the output of the source, positrons are slowed down in a solid target. Frozen neon is used as a moderator. For this purpose, a system of cryocooling of the source and the neon supply line have been assembled. A method of detection of slow positrons has been developed and tuned. The first experiments with the frozen moderator have been performed. A continuous beam of slow positrons with an average energy of 1.2 eV and spectrum width of 1 eV has been obtained.     

Positron injector for LEPTA

The low energy positron injector for the Low Energy Particle Toroidal Accumulator (LEPTA) accumulator was assembled at the Joint Institute for Nuclear Research (JINR). Key elements of the injector have been tested. The cryogenic source of slow positrons was tested with a test isotope ²²Na of the initial activity of 0.8 MBk. A continuous slow positron beam intensity of 5.8 × 10³ particle per second with an average energy of 1.2 eV and a spectrum width of 1 eV has been obtained. The achieved moderator efficiency is about 1%. The accumulation process in the positron trap was investigated with electron flux. The lifetime of the electrons in the trap, τ_life ≥ 80 s and capture efficiency ɛ ∼ 0.4, were obtained. The maximum number of accumulated particles was N _exper = 2 × 10⁸ at the initial flux of 5 × 10⁶ electrons s⁻¹. The text was submitted by the authors in English.     

System of thermostatic control on Peltier thermopiles and microprocessor control for a portable NMR relaxometer

Liquid equipment for thermostatic control of samples with accuracy better than 0.1 degree C within the temperature range from -20 to +70 degree C is designed for small-sized NMR spectrometers. The difficulty in using this equipment is a thermomodule based on the Peltier effect. The temperature control system is based on a single crystal microcomputer. The equipment fits modern small-sized NMR spectrometers, which facilitates medical and biological studies.     

某型火控雷达维修训练模拟器设计与应用

为了提高教学效果,减少实装损耗,加强新装备保障能力,研制某型火控雷达维修训练模拟器;该模拟器以网络化主控计算机单元为核心,由实装操作分系统、虚拟装备分系统、实装部组件分系统、动感分系统、联动分系统组成,具有操作训练、维修训练、武器系统联动训练及训练评估等功能,解决了新型雷达装备教学与训练中实装损耗大、装备数量少、训练效率低等问题;该模拟器已用于多个雷达专业的操作、维修、综合演练等教学实践中,与以往的训练设备相比可操作性好,应用范围广,教学效果明显;文中介绍了模拟器的功能结构、硬件设计、软件设计及其应用。     

基于SOPC的嵌入式网络化测控网关设计

为了实现测控设备的网络化远程访问控制,必须设计用于IEEE 488等测控接口总线协议与网络协议转换的网关设备,给出了一种基于SOPC技术的嵌入式网络化测控网关设计方法,其中借鉴了基于组件的模块化设计思想,采用固件分层设计和多语言混合编程模式,能够融合多种测控协议,将LAN、GPIB、USB、RS232等接口集成到了一个系统上,实现了嵌入式web服务器功能,客户端能够基于IE等浏览器实现测控设备的远程访问控制;最后给出了系统综合验证方法,结论表明:系统功能完善,符合网络化、模块化、通用化和智能化的发展方向。     

Fiber-optic equipment for monitoring technological processes

The results on the development and implementation of optical systems for monitoring technological processes are presented. The developed equipment is based on the principles of tandem low-coherence interferometry. The equipment allows contactless remote monitoring of the optical thickness of transparent layered objects with nanometer resolution immediately during technological processes. One of the versions of the equipment intended to control the sheet glass thickness is successfully implemented in industry. The second version intended for monitoring semiconductor nanostructure fabrication is successfully applied to control the growth processes under condition of metal-organic vapor-phase epitaxy and the plasma-chemical etching processes.     

基于PLC的常规加注模拟训练设备控制系统的设计与实现

根据常规加注模拟训练设备实际的控制要求,设计了以PLC作为核心控制器的训练设备控制系统,概述了该系统的硬件设计,详细介绍了基于集成开发环境的软件设计;经过实验室测试和现场联调,该系统实现了多种加注工艺流程、数据实时监测、手/自动控制、故障分析及处理、参数设置与储存等功能,不仅能够满足训练设备所有的控制要求,还具备强大的远程控制能力和人机交互能力,有良好的可靠性和实时性。     

Ka频段飞行器测控与通信系统设计

传统基于S频段的统一载波测控系统受工作频率低、频带窄的特点限制,无法满足各类飞行器测控与通信系统对高速数传、宽带扩频、克服“黑障”、抗干扰等方面日益增长的需求,给系统设计带来了新的挑战。本文提出一种基于Ka频段直接序列扩频通信体制的实现遥测、外测、遥控等功能的飞行器测控与通信系统,给出了系统架构及主要设备组成,同时对地面测试方案进行了介绍。该系统具备体积小、频带宽、扩展性好等特点,可用于未来空间飞行器特别是小型化、大容量飞行器设计。     

容积式制冷机组性能测试的一种改进实验装置

针对容积式压缩机组测试设备的初始投资高,能耗高的问题,介绍了一种改进的实验装置.其制冷量测量采用制冷剂液体流量计法。研究测试结果表明:(1)改进实验装置控制精度较高;(2)改进的实验装置的相对误差为1.5%。与房间量热计相比,该实验装置节能72.2%且初始投资节省60%。     

飞行器遥测设备与综控机一体化设计

随着新一代飞行器技术的快速发展,对其体积、航程以及信息化程度的要求越来越严格。为此,提出了飞行器遥测设备与综控机的一体化设计,利用的数据监测与处理模块替代传统飞行器上单独的遥测设备,将其集成到综控机当中,大大节约了飞行器空间,提高了其信息处理与监测能力。该模块基于NandFlash存储器、DSP/BIOS实时操作系统千兆以太网接口以及PCM接口,能够实现大量数据的实时存储与传输。经大量试验证明：NandFlash存储器能够可靠的记录大量实验数据,千兆以太网接口可以很好的实现飞行器系统与测试设备之间的高速数据传输,通过PCM接口能够组织完成遥测数据的实时发送,既具备传统遥测设备的功能,又提高了数据处理、存储与监测的能力。     

配电房轨道式自动巡检机器人控制系统设计与实现

针对配电房等室内电力系统供电设备自动巡检的需求,提出了以微控制器MSP430F5438为核心的自动巡检机器人控制系统总体设计方案。采用模块化方法完成了控制系统硬件电路设计,主要包括：主控模块、电源模块、运动控制模块、通信模块和数据采集模块。介绍了控制系统软件的总体流程,完成了控制系统嵌入式软件及其上位机监控软件的设计。实验结果表明,所设计的控制系统应用于巡检机器人可以实现对配电房供电设备的自动巡检,从而验证了控制系统的有效性与合理性,具有显著的推广应用价值。     

Experiments on the active control of transformer noise

This paper describes an experiment which demonstrates how a useful degree of active noise control can be achieved with ordinary sound amplification and reproduction equipment. A loudspeaker positioned next to a large pair of noisy electricity transformers was made to mimic their noise but in antiphase. The aim of the study was to investigate the degree to which the “antisound” would cancel a disturbing noise heard in a nearby office. Some 20 decibels of control was achieved very easily for the 100 Hz component of the noise but the higher frequency sound could only be controlled in localized patches. The experiment suggests that sounds of discrete frequencies of less than 100 Hz are relatively easily controlled with unsophisticated audio equipment, but that useful control of higher frequency elements is much more difficult.     

The Electrotechnical Complex of the KTM Tokamak Pulsed Power Supply System

The pulsed power supply equipment belongs to the basic technological systems intended for implementing the required scenarios of changing currents in magnetic coils. The accuracy of implementing these scenarios directly determines the possibility of attaining the plasma breakdown and the required ultimate plasma parameters. Given the uniqueness of each facility under construction in the world and the installed capacity of the electrotechnical equipment applied in the power supply configuration, one can state with confidence that the construction of similar power supply complexes and their control systems, the optimization of their electrotechnical parameters, and the subsequent accident-free operation are vital tasks in mastering controlled thermonuclear fusion technologies. This paper describes the pulsed power supply system of the KTM tokamak (Kazakhstan) designed for material testing, the digital control system for its power conversion equipment, electrotechnical solutions adopted in the design of the KTM tokamak pulsed power supply system, and findings of tests of some items of equipment and their components. The tests have demonstrated sufficient efficiency of the adopted electrotechnical solutions and the possibility of applying them to implement the pulsed power supply systems for small and medium sized tokamaks.