静电除尘用脉冲电源拓扑研究

对一种静电除尘用脉冲电源高压拓扑进行了研究,通过模态分析谐振状态及谐振后的震荡转态,研究耦合电感、耦合系数及谐振腔电阻对静电除尘器电源输出电压的影响,优化设计耦合电感及耦合系数。通过理论分析,推导出各部分激励对负载的传递函数表达式,并绘制三维变参数曲面图进行系统参数分析,最后搭建1.5 k V的脉冲电源系统,验证静电除尘器电源拓扑的工作原理及理论分析设计的正确性。     

我国开关电源发展的思考

文章综述了开关电源的国内外市场及应用情况和发展趋势。在回顾和分析我国开关电源发展历史和现状的基础上，对我国开关电源未来的发展提出了建议。     

TL494及其在半桥变换开关电源中的应用

介绍了电压驱动型脉宽调制器件TL494的脉宽调制特性，并对其在半桥变换开关电源中的应用情况做了分析。     

Low power DDA-based instrumentation amplifier for neural recording applications in 65 nm CMOS

The low power instrumentation amplifier (IA) presented in this paper has been designed to be the front-end of an integrated neural recording system, in which common-mode rejection ratio (CMRR), input referred noise and power consumption are critical requirements. The proposed IA topology exploits a differential-difference amplifier (DDA) whose differential output current drives a fully differential, high-resistance, transimpedance stage, with an embedded common-mode feedback loop to increase the CMRR. This stage is followed by a differential-to-single-ended output amplifier. Low-power operation has been achieved by exploiting sub-threshold operation of MOS transistors and adopting a supply voltage of 1 V. Simulation results in a commercial 65 nm CMOS technology show a 1 Hz to 5 kHz bandwidth, a CMRR higher than 120 dB, an input referred noise of 8.1 μVrms and a power consumption of 1.12 μW.     

1100W开关电源前级功率因数校正技术的研究

功率因数校正技术作为雷达电源系统的一项关键技术应用到开关电源中 ,有利于电源技术指标的提高 ,对雷达供电系统的有效运行带来很大的益处 ,越来越成为电源行业研究的热点。介绍了功率因数校正技术的发展和特点 ,分析了平均电流型技术 ,给出了 110 0W开关电源前级的功率因数校正电路的设计方法和实验结果     

低能量激光鼻腔照射疗法的临床应用研究

通过鼻腔照射疗法对 6 8例脑梗患者进行疗效分析 ,经过三个疗程的治疗 ,总有效率达到 89.7%。此种疗法的明显优势 :不需要静脉穿刺 ,鼻腔照射疗法为低能量激光的应用提供了一个有效的途径     

Nonuniform sampling theorems for random signals in the linear canonical transform domain

Nonuniform sampling can be encountered in various practical processes because of random events or poor timebase. The analysis and applications of the nonuniform sampling for deterministic signals related to the linear canonical transform (LCT) have been well considered and researched, but up to now no papers have been published regarding the various nonuniform sampling theorems for random signals related to the LCT. The aim of this article is to explore the nonuniform sampling and reconstruction of random signals associated with the LCT. First, some special nonuniform sampling models are briefly introduced. Second, based on these models, some reconstruction theorems for random signals from various nonuniform samples associated with the LCT have been derived. Finally, the simulation results are made to prove the accuracy of the sampling theorems. In addition, the latent real practices of the nonuniform sampling for random signals have been also discussed.     

A thyristor- and thermistor-based inrush current limiter for DC-link start-up

Large inrush currents can be harmful to equipment subjected to it and can also disturb other devices through voltage dips. Traditional ways of dealing with large inrush currents include the usage of parasitic elements in the supply, negative temperature coefficient (NTC) resistances and start-up relays. These solutions have several disadvantages among which are a non-negligible standby consumption, using a relay or a compromise between inrush current and load losses using an NTC. This paper proposes a solution which solves these disadvantages. The proposed circuit uses a semi-controlled bridge rectifier requiring a very low standby power consumption and is capable of withstanding grid interruptions. Moreover, it is designed to power on only when the load is not too heavy. This is accomplished by the use of positive temperature coefficient thermistors. The presented solution can be used for DC-link start-up circuits in applications with a power range from several watts up to a few kilowatts and it is particularly suitable for on-board battery chargers designed for electrical vehicles.     

1030nm高重复频率纳秒脉冲全光纤放大器

采用脉冲调制的单模带尾纤输出的半导体激光器作为种子源,以掺镱光纤为增益介质,采用主振荡功率放大(MOPA)结构,实现了1030nm全光纤脉冲激光放大。脉冲重复频率在50～100kHz范围内可调,在重复频率50kHz时,实现了脉冲宽度为6.53ns,峰值功率为16.08kW的脉冲输出,相应的斜率效率为69%,输出激光的中心波长在1029.49nm。实验还研究了不同重复频率下输出激光脉冲的时域特性。该激光器的输出波长在激光雷达探测器的光谱响应范围内,可作为激光雷达发射光源。     

Ku波段宽带大功率多芯片合成设计

设计针对多个Ku波段宽带MMIC功率放大芯片进行大功率合成.对波导多路功率合成结构进行了分析,基于单个Ku波段6W功放单片,进行了16路的功率合成,研制出了工作在12～17 GHz,带宽达到6 GHz的固态功率放大器.通过测试发现该固态功率放大器的输出功率≥70 W,功率增益≥15 dB,工作电压48 V,效率≥16％...