中性束注入器用串联高压缓冲器优化设计

为了优化中性束注入器(NBI)用高压缓冲器的布局,分析了缓冲器结构设计参数和缓冲器性能的相互关系,并通过等效电路仿真模型修正了缓冲器放电峰值电流经验公式,得到了不同激励信号下串联高压缓冲器在高频脉冲放电情况下的特性,最后,在高压缓冲器理论分析和仿真分析的基础上,对设计的非晶缓冲器和Deltmax缓冲器串联高压测试件进行了短路放电测试,得到了短路放电瞬间串联缓冲器的分压和回路的放电电流。放电实验结果表明,黑色非晶缓冲器感应电压频率响应比较快,Deltmax缓冲器可以消耗更多的故障电流能量,非晶缓冲器和Deltmax缓冲器这2种不同直流缓冲器的串联能够有效地抑制高压直流故障短路电流并吸收故障电能。     

A new digital Gaussian pulse shaping algorithm based on bilinear transformation

Nuclear pulse signal needs to be transformed to a suitable pulse shape to remove noise and improve energy resolution of a nuclear spectrometry system. In this paper, a new digital Gaussian shaping method is proposed.According to Sallen-Key analog Gaussian shaping filter circuits, the system function of Sallen-Key analog Gaussian shaping filter is deduced on the basis of Kirchhoff laws. The system function of the digital Gaussian shaping filter based on bilinear transformation is deduced too. The expression of unit impulse response of the digital Gaussian shaping filter is obtained by inverse z-transform. The response of digital Gaussian shaping filter is deduced from convolution sum of the unit impulse response and the digital nuclear pulse signal. The simulation and experimental results show that the digital nuclear pulse has been transformed to a pulse with a pseudo-Gaussian, which confirms the feasibility of the new digital Gaussian pulse shaping algorithm based on bilinear transformation.     

浅谈村村通直播卫星接收机原理与维修

一、电源部分 所有卫星接收机的电源用的都是开关电源.甚至不同厂家所用的电源都大同小异.如神州公司、上广电、海信都用到FSDL0165RN开关电源控制芯片,同洲用5L0365RV,九洲用STR-A6151,海尔用TNY-278PN开关电源控制芯片.     

On the Sequential Control of ITER Poloidal Field Converters for Reactive Power Reduction

Sequential control applied to the International Thermonuclear Experimental Re- actor （ITER） poloidal field converter system for the purpose of reactive power reduction is the subject of this investigation. Due to the inherent characteristics of thyristor-based phase-controlled converter, the poloidal field converter system consumes a huge amount of reactive power from the grid, which subsequently results in a voltage drop at the 66 kV busbar if no measure is taken. The installation of a static var compensator rated for 750 MVar at the 66 kV busbax is an essential way to compensate reactive power to the grid, which is the most effective measure to solve the problem. However, sequential control of the multi-series converters provides an additional method to improve the natural power factor and thus alleviate the pressure of reactive power demand of the converter system without any additional cost. In the present paper, by comparing with the symmetrical control technique, the advantage of sequential control in reactive power consumption is highlighted. Simulation results based on SIMULINK are found in agreement with the theoretical analysis.     

网络教学在高校田径教学中的运用

随着计算机网络的发展,在教学领域中出现了一种新的教学形式网络教学,其逐渐渗透到体育各项目的教学中,它的出现尤其对传统的田径教学组织形式产生了深远影响.通过阐述田径教学的现状与网络教学的优势,提出将网络教学运用于传统高校田径教学中的思考,将网络教学这一先进的教学理念和手段运用到体育传统项目田径的教学过程中,是促进田径教学改革,适应当前教育发展的必然趋势.