加速器直流电源纹波抑制研究

为降低加速器直流励磁电源的输出电流纹波,研究了一种抑制电源输出电流纹波的直流有源滤波器(DAF)。采用检测负载电压的方式,解决了电流纹波幅值小难以检测的问题。通过控制DAF吸收或注入谐波电流来降低电压纹波,进而达到降低电流纹波的目的。设计的buck/boost电路作为有源滤波器的主电路,能维持储能电容电压的稳定,省去了整流电路。对设计方案进行了仿真并搭建了实验样机进行验证,实验结果表明,设计的DAF对低频纹波有一定的抑制效果。     

混合模式低噪声3 kV高压直流电源设计

高压直流电源是电离室等核辐射探测器的关键部件。针对需要3 kV左右高压的电离室,本文研制了0～3 kV连续可调的低噪声、高效率、小体积及高稳定性的高压直流电源。该高压直流电源系统采用线性与开关混合模式设计,兼顾了转换效率与低噪声。核心部分升压转换部分采用线性罗耶谐振电路与高频变压器实现,保证足够低的高压电源输出纹波。罗耶谐振电路的供电电源则由边沿时间控制型超低噪声开关稳压器LT1534提供,从而实现了混合模式高压直流电源的设计。高压直流电源输出部分采用二阶RC滤波电路进一步降低了输出电压的纹波。实测输出电压范围为0～3 kV,静态功耗为0.4 W,3 kV输出时纹波为16.55 mV,由此可知该电源可用于低噪声的核辐射探测器供电场合。     

低纹波微型X射线管高压电源的研制

国内研发的X射线高压电源体积普遍较大,不适合微型X射线管的要求。针对微型X射线管的特点,本文设计了一种低纹波、小体积高压电源,其输出电压在0~-40kV范围内可调。电源的逆变电路采用罗耶谐振电路,并引入UCC2973控制芯片以提高其效率。在电源的升压部分设计了高频变压器、双向倍压整流电路,以进行两级升压。通过电阻分压后取样反馈的方式进行稳压。电路工作在线性状态,无开关噪声。测试结果表明,电源的输出电压纹波低于0.3%、稳定度优于0.12%/10h,可满足微型X射线管的需求。     

G-M计数管新型直流高压电源设计

G-M计数管工作需要性能稳定的直流高压电源供电。该直流高压电源利用输出采样与基准电压比较负反馈实现高压稳定控制,比较不同闭环放大倍数下直流高压电源性能,采取优化闭环放大倍数。该直流高压电源具有结构简单、体积较小、低纹波等特点,其输出电压在0~1 100 V范围内连续可调。测试结果表明:当高压典型输出电压为400 V时,电压稳定度可达0.17%,输出电压纹波峰最低峰值为62 m V,可满足G-M计数管的需求。     

Simulation and test results of low-order band harmonic filters to decrease resonance phenomenon in the KSTAR power system

The superconducting magnet power supply which supplies superconducting magnet coil (SC) with the power to generate plasma during a KSTAR experiment for nuclear fusion research is a nonlinear load. Characteristic harmonics are generally produced since it converts AC to DC using 6 or 12 pulsed operation. However, non-characteristic harmonics or inter-harmonics are generated according to output control characteristics. Also, 95% out of the power generated from superconducting magnet coil is reactive power. Therefore, harmonic and reactive power occurring during operation have some bad influences such as voltage drop, voltage distortion and decrease in power factor on the KSTAR power system, and reactive power compensator (RPC) & harmonic filter (HF) system which is able to compensate harmonic and reactive power at the same time was established and has been operated [1]. However, out of non-characteristic harmonics and inter-harmonics caused by output control characteristics of superconducting magnet power supply, the more compensation volume of the RPC & HF system increases, the more voltage distortion with harmonic expansion is caused by harmonics in a low-order band due to the parallel resonance in a low-order band between the KSTAR power system and the RPC & HF system. As a result, it has serious effect on the injection capacity restriction of the RPC & HF system, the unstable operation control of superconducting magnet coil, and the operation of main cooling facilities. This paper presents reasons of the resonance phenomenon of the KSTAR power system and suggests a design plan of additional facilities for stable operation of the KSTAR power system, and proves their effects through the simulation and test results.     

LLC谐振恒流恒压高压充电电源技术研究

高压充电电源输出电压的稳定性是脉冲调制器的关键技术指标,需对其进行研究,以提高其输出稳定性。基于激磁电感、谐振电感、谐振电容（LLC）谐振变换器的工作原理,根据LLC等效电路得到了LLC谐振电路的电压增益曲线,分析了LLC谐振变换器工作区间的特性,提出了平面绝缘芯变压器的选择依据和设计方法,通过测量实际变压器得到变压器的参数;根据变压器参数选择了LLC谐振变换器谐振频率和工作频率,并通过LLC谐振变换器电路的推导,详细计算了高压充电电源输出电压的纹波幅值。结果显示,计算结果优于设计指标。经实验验证,叠层磁芯LLC谐振变换器高压充电电源的稳定性能达到了设计要求。     

空间辐射探测器滤波电路的设计

为满足粒子辐射探测器高压电源高稳定、低纹波的要求,设计一种LC和RC混合滤波电路来降低电源纹波,并进行理论分析、PSpice仿真和试验对结果进行验证。按照这种设计实现的某型号卫星高能粒子探测器的高压电源,输出电压稳定、纹波系数小,达到设计目的。试验证明这种电路设计简单、高效,可为相关电路设计提供参考。     

低能加速器开关电源研制

利用直流脉宽调制技术以及半桥变换电路,为一种低能电子直线加速器成功研制阳极开关电源。根据开关电源的特点,对该电源中低压和高压部分进行详细设计。低压部分采用SG1525A为控制核心,实现脉宽调制、软启动、稳压调节以及过压保护功能。该开关电源主要指标:输出电压0~800V,最大电流400 m A,工作频率为18.5 k Hz,纹波峰值系数为0.9‰,达到设计要求。     

数字化X荧光仪电源的最优化设计

针对数字化X荧光仪的低功耗、低噪声等要求进行了电源最优化设计。文中对数字梯形滤波器进行了Simulink仿真,根据仿真结果得到最佳的M,N系数,由此确定微分电路的时间常数,最后确定高压电源的最佳开关频率点,降低了高压偏置电源噪声对系统的干扰。还分析了数字梯形滤波器及高速ADC采样的特点,设计了最优化的低压供电系统,进一步降低低压电源对系统的干扰。为了提高Si-Pin探测器制冷电源的供电效率,采用了高效率DC-DC、LDO芯片与检流芯片完成高效率恒流源的设计。实测高压电源的交流纹波小于3.5 mV,带载功耗小于70 mW,恒流源的带载转换效率83%,纹波电压小于12 mV,相同条件下采用文中电源系统可提高谱线的能量分辨率。     

MAGY: An innovative high voltage–low current power supply for gyrotron

From the electrical point of view, the body and the anode of high power gyrotrons behave as capacitive loads. A highly dynamic power supply is, therefore, hard to achieve. The MAGY concept (Modulator for the Anode of a triode type GYrotron) embodies an innovative solution to manage the capacitive current ensuring a very low ripple on the output voltage. It consists of a series of independent, bi-directional and regulated DC sources. Compared to existing topologies, this solution requires a smaller number of power modules. It avoids internal high frequency modulation and simultaneously offers high resolution of the output voltage and a wide range of operating scenarios.     

Design and Development of a Power Supply System for NBI Test Stand of EAST

A neutral beam injector (NBI) test stand was constructed to develop a multi-megawatt prototype ion source as an auxiliary heating system on experimental advanced superconducting tokamak. A power supply system for the NBI test stand components such as a set of dc power supplies for plasma generator, a dc high voltage power supply of a tetrode accelerator, a transmission line and a surge energy suppressor. Stable arc discharges of the plasma generator with hydrogen gases for 100 s long pulse have been produced by six Langmuir probes feedback loop regulation mode to control the arc power supply. The 4 MW hydrogen ion beam of 1 s is extracted with beam energy of 80 keV and the beam current of 52 A. The dc high voltage power supply for the plasma grid of the prototype ion source was designed to contribute maximum voltage of 100 kV and current of 100 A. The high voltage power output is continuously adjustable to satisfy with plasma physics experiment in operation frequency of 10 Hz. To prevent damage of the beam source at high voltage breakdown, core snubber using deltamax soft magnetic materials have been adopted to satisfy the input energy into the accelerator from the power supply can be reduced to about 5 J in the case of breakdown at 80 kV. For the transmission line, a disc shape multi cable coaxial configuration was adopted and which the dimension of the diameter is 140 mm at the core snubber. The major issues of discharge characteristics with long pulse and beam extraction with high power for the prototype ion source were investigated on the NBI test stand.     

高能同步辐射光源储存环快校正磁铁电源设计

高能同步辐射光源（HEPS）具有0.1 nm·rad的超低发射度,对束流稳定度提出了较高要求,研制1台高性能快校正磁铁电源用来提高快速轨道反馈系统（FOFB）的性能以提升束流稳定度。电源样机采用新颖的多电平级联拓扑结构提升电源样机的动态性能,使用基于数字控制的新颖控制方法实现样机的动态性能提升。软件仿真与样机试验数据证明,电源样机具有10 kHz小信号带宽、电源阶跃响应时间小于70 μs、输出电流纹波低于20 ppm,电源样机可很好地满足HEPS建设需求。     

Design of Fast Corrector Magnet Power Supply for HEPS Storage Ring

The high energy photon source (HEPS) has an ultra-low emittance of 0.1 nm·rad, which puts forward high requirement for beam stability. A high performance fast corrector magnet power supply was developed to improve the performance of the fast orbit feedback system to improve the beam stability. The prototype adopted a novel multi-level cascade topology structure to improve the dynamic performance, and a novel control method based on digital control was used to improve the dynamic performance of the prototype. Software simulation and the prototype test data show that the prototype has a small signal bandwidth of 10 kHz, step response time lower than 70 μs, output current ripple of less than 20 ppm. The power supply prototype can meet the requirement of HEPS.     

A High Performance 4500 Volt Electron Multiplier Bias Supply for Satellite Use

A tuned-secondary sinewave oscillator combined with a Cockcroft-Walton voltage multiplier has been developed which produces 40 ?A at 4500 volts from 12 VDC with 80% efficiency. Optimum efficiency is obtained by considering the Cockcroft-Walton multiplier as part of the oscillator design. Equations are developed for calculating the multiplier output voltage and ripple as a function of the oscillator output frequency and amplitude, the capacitance of the multiplier, the number of multiplier stages, and the load current. The Atmosphere Explorer Photoelectron Spectrometer electron multiplier bias supply is also described to illustrate practical design tradeoffs and techniques employed when the supply is used in a satellite-borne particle detection experiment.     

高能同步辐射光源高精度直流稳流电源样机研制

即将建造的高能同步辐射光源对四极磁铁电源的性能提出了很高的要求。为了掌握此类型磁铁电源的关键技术并解决其技术难点,在验证装置中研制了高精度直流稳流电源样机。样机采用模块化设计,利用数字、模拟调节器相结合的控制方式,实现对输出电流的高精度控制。为了实现电流稳定度的设计指标,样机采用自主研发的高精度数字控制器和DCCT,对闭环控制中的关键器件进行了恒温控制。实验结果表明,样机的电流稳定度达到了10 ppm,电压纹波低于设计指标5 mV。样机的其他性能指标也均达到了物理设计的要求,并最终通过验收测试。     

Study of the EAST Fast Control Power Supply Based on Carrier Phase-Shift PWM

EAST(experimental advanced superconducting tokamak) fast control power supply is a high-capacity single-phase AC/DC/AC inverter power supply,which traces the displacement signal of plasma,and excites coils in a vacuum vessel to produce a magnetic field that realizes plasma stabilization.To meet the requirements of a large current and fast response,the multiple structure of the carrier phase-shift three-level inverter is presented,which realizes parallelled multi-inverters,raises the equivalent switching frequency of the inverters and improves the performance of output waves.In this work the design scheme is analyzed,and the output harmonic characteristic of parallel inverters is studied.The simulation and experimental results confirm that the scheme and control strategy is valid.The power supply system can supply a large current,and has a perfect performance on harmonic features as well as the ability of a fast response.     

The Harmonic Analysis of RMP Coil Power Supply in EAST TOKAMAK

In EAST TOKAMAK, resonant magnetic perturbation (RMP) coils, which are powered by RMP coil power supply (PS), are set to research edge localized mode, resistive wall mode and error field correction. In order to meet the requirements of fast response and output voltage ripple proposed by physical experimenters, the structure of multiple modules using cascaded carrier phase-shifted PWM H-bridges is adopted, which enhances the equal switch-frequency of the PS and improves the quality of output voltage. In the paper, theoretical calculation applying Fourier analysis is given to analyze its harmonics. Both simulation results on Matlab and test results of output voltage ripple show that the RMP coil PS can meet the requirements.     

基于前馈控制的棒位探测器励磁电源研究与设计

提出一种基于前馈控制的棒位探测器励磁电源设计方案,该方案采用高频开关整流逆变电路设计,在传统比例积分(PI)控制的基础之上加入了前馈控制,用以抑制可测不可控的干扰因素对控制对象的影响,并通过理论分析与仿真试验,验证了本文提出的设计方案在保证控制响应时间的同时降低了输出纹波,提高了电流幅值精度。     

微型X射线管灯丝电源的研制

根据微型X射线管的特点,设计了基于推挽电路和闭环反馈电路的灯丝驱动电源。采用了UCC3808脉宽调制(Pulse Width Modulation,PWM)控制芯片产生两路相位相反的PWM信号,并经由UCC37324金属氧化物半导体(Metal-Oxide-Semiconductor,MOS)管大电流驱动器提高驱动效率,实现推挽结构的后端驱动电路。闭环反馈电路的设计采用精密电阻将管电流的信号转换为等比例的电压信号引入到反馈环节,通过系统自身的闭环控制实现管电流的恒定,并保持高效率和低功耗。实验首先通过外接1.5?的功率电阻测量系统功率,测得输入功率为11 W,效率超过80%,符合灯丝电源的功耗指标要求;然后连接实际的X光管灯丝,经测试可正常工作,管流稳定度为0.227%。     

The Circulating Current Analysis and Parameter Design of Interphase—Reactor of HT—7U Toroidal Power Supply

This paper analyzes the circulating current which is produced by HT-7U superconducting toroidal power supply-two sets of two-reverse-star converter with an interphase-reactor in parallel running on the basis of the output voltage mathematical equation of three-phaase semi-wave converter circuit.A new iden of omitting interphase-reactor between two converters is proposed,and the parameter design of interphase-reactor of HT-7 toroidal power supply is presented.Simulated results demonstrate the validity of this new project.