12W模块化AC/DC开关电源

<正> 各种PWM控制的开关电源正朝着电路简洁、功能完善、体积更小、可靠性更高的方向发展,本文介绍的WH12系列AC/DC模块化开关电源体现了这一发展方向。 WH12系列模块化开关电源尺寸均为48×38×23mm的四端器件,体积仅与一只3W频变压器相     

微功耗工频脉宽调制开关电源（下）

介绍一种开关电源,采用工频脉宽调制方法,所有功率器件都工作在工频,既不产生高频损耗,也不产生EMI干扰,该开关电源不采用复杂的PWM控制芯片,电路简单,安全可靠,寿命长,故障少,与传统高频脉宽调制开关电源相比,成本、体积、重量、功耗都减少90％。     

微功耗工频脉宽调制开关电源（上）

介绍一种开关电源,采用工频脉宽调制方法,所有功率器件都工作在工频,既不产生高频损耗,也不产生EMI干扰,该开关电源不采用复杂的PWM控制芯片,电路简单,安全可靠,寿命长,故障少,与传统高频脉宽调制开关电源相比,成本、体积、重量、功耗都减少90%。     

基于DSP控制的数字开关电源综述

简要分析了开关电源的模拟控制方式的特点。为了将数字控制的优点引入开关电源,进一步提高开关电源的性能,文章介绍了一种基于DSP芯片TMS320LF2407控制的数字开关电源。分析比较表明了基于DSP控制的开关电源具有稳定快、失真小、负载对系统影响小的特点,数字控制技术可以在开关电源中推广应用。     

开关电源的现状及未来——抑制高次谐波电流 采用表面贴装技术

开关电源从七十年代开始迅速普及，如今已经广泛地用于计算机、通信设备、控制装置及家用电器等电子设备中；在日本，虽然其电子产业不断将生产基地转移到海外，但国内开关电源的年产量仍然在四千万台以上。迄今，开关电源厂家一直在探讨电路技术开发新器件及新材料、改进装连方法等方面进行努力，以缩小体积、减轻重量、提高效率和可靠性、降低价格，并已经取得若干进展；最近，开关电源面临的新课题，是环境适配性，包括噪声与谐波等的电磁适配性、同人类之间的安全适配性等。小型、轻量、廉价提高频率已无余地为了使开关电源达到缩小体积…     

电流控制PWM开关电源

介绍电流控制PWM开关电源的基本原理，并将其与电压控制PWM开关电源进行比较，指出了电流控制PWM开关电源的优点。最后给出了一个实用的电流控制PWM开关电源进行比较，指出了电流控制PWM开关电源的优点，最后给出了一个实用的电流控制PWM开关电源电路。     

单相两级有源功率因数校正变换器的研究

文中对两级有源功率因数校正变换器进行研究,设计了一台510W两级式开关电源。该电源前级采用平均电流控制的Boost型PFC电路,实现功率因数校正;后级采用不对称半桥型DC／DC变换器,实现开关管的零电压开关。控制电路采用PFC／PWM复合控制芯片ML4824,缩小电源体积。通过实验证实该开关电源具有高功率因数与高效率的特点。     

开关电源初级电路控制器CW1840

一、概述近年来,高频开关电源因其极高的效率与功率体积比(power to volume ratio),已成为大多数现代电子系统的主要功率源。图1为普通脱线(off-line)开关电源的基本结构框图。为使电源的输出在输入总线或负载变动时仍保持恒定,通常均如图所示采用对输出直接监测取样,然后送至控制单元,由控制单元向     

小功率、高功率、高频DC—DC开关电源的研制

本介绍了一种小功率DC－DC高频开关电源的研制过程,电路以UC3842作为电源的控制芯片,主要阐述了该电路的原理、变压器的设计以及实现小体积、高效率的技术要点,并给出了研制样机。     

新型数控高压电源的研制

针对电流变技术对控制高压电源要求的快速通断、智能控制以及缩小体积的要求,采用单片机技术与高频开关电源技术,设计制作了一台用于电流变元件控制的数控高压电源。本高压电源系统具有输出稳定、控制方便、体积小等优点,能满足电流变技术所要求的高电压、低电流以及高稳定性等特性。     

电流型控制芯片UC3842应用于重频升压电源的研究

新型开关电源控制芯片UC3842基于电流型控制稳压技术原理,外围电路少,使用方便。文中介绍了一种利用UC3842的重频升压电源的设计方法,它克服了以往PWM开关电源开关损耗大、干扰严重的缺点。     

一种基于UC3843的单端反激式开关电源

本文介绍了一种电流控制型PWM控制器UC3843的特点和工作原理,并分析了其构成开关电源的整体电路结构和工作原理,最后提出了一种基于UC3843的单端反激式开关电源的设计方法     

Switchable dual-wavelength Raman erbium-doped fibre laser

A fibre Bragg grating feedback fibre laser with both Raman and erbium-doped fibre pumps is proposed. Dual-wavelength switching is achieved by controlling the power of the Raman pump. The characteristics of the dual-wavelength switching are studied experimentally, and the mechanism is explained physically.     

Switching flow-graph nonlinear modeling method formultistate-switching converters

Switching power converters operating in a multistate switching mode (more than two states) feature multidimensional control over their state variables. In this paper, a large-signal multistate modeling method is developed based on the switching flow-graph method to study the steady-state and dynamic properties of pulse-width-modulated (PWM) multistate-switching power converters for the continuous conduction mode. This modeling method translates a switching power converter directly to its graphic dynamic model and uses graphical representation to reveal the cause and effect relationship of the dynamics within a multidimensional power converter. A three-state buck-boost circuit is conceived with two duty ratios controlling two outputs as an example to test this modeling method. Experimental results confirm the theoretical prediction. This multistate-switching flow-graph modeling method is very general, easy to use and accurate, and it provides deep physical insight for engineering design     

一种太阳能电动车用开关电源的设计

设计了一种供太阳能电动车无刷直流电机控制模块使用的半桥型开关电源电路,在实现输出采样反馈的同时,利用SG3525芯片的关闭功能设计了过流检测电路,有效防止过电流或过电压对控制系统的危害。实验结果表明,该电路具有响应快、稳定性好、输出电压精度高等优点,很好地满足了太阳能电动车无刷直流电机控制模块的供电需求。     

IOT Based Augmented Perturb-and-Observe Soft Switching Boost Converters for Photovoltaic Power Systems in Smart Cities

This paper focuses on IOT based soft switching boost converter based solar energy applications for smart cities and making cities smarter and greener around the globe. It presents one of the applications of the Internet of Things to design and implementation of a highly efficient boost converter used for powering the Arduino and the Bluetooth device for controlling the switching of the led and buzzer by using smart city applications. The soft switching boost converter is essential to maximize the low-level voltage obtained from the solar board to the enhanced voltage conversion ratio for the efficient electric power generation. In this paper, the three separate methodologies of DC–DC boost converters with additional resonant/snubber circuit and resistive load associated with solar panel modules proposed with maximum power point tracking (MPPT) control. The MPPT is obtained by modified augmented perturb and observe algorithm. IoT helps Smart City(SC) systems to support various network functions throughout the generation, transmission, distribution and consumption of energy by incorporating IoT devices (such as sensors, actuators and smart meters), as well as by providing the connectivity, automation and tracking for such devices. It is utilized to extract the most extreme power from solar panel by controlling the duty ratio of the suggested soft switching based boost converter. In this paper a smart IOT system is used to control and monitoring the effect of reference power variations, parameter values to the voltage control to the converter. The solar panel, boost converter and the MPPT is modeled using MATLAB/SIMULINK environment and reach the power transfer efficiency up to 97%.     

A new extension of one-cycle control and its application toswitching power amplifiers

A new extension of one-cycle control is proposed for controlling DC-AC switching converters. Instability, encountered in the implementation, was studied and resolved. An automatic switching-error correction scheme is developed. This control technique overcomes the nonlinearity of DC-AC switching converters, eliminates the crossover distortion, rejects the power source ripple, and achieves a large dynamic range and a wide bandwidth. A half-bridge experimental circuit was built to verify the theory. This new extension is suitable for high efficiency, small volume, and low distortion audio power amplification     

Integrated ZVS DC–DC converter with continuous input current and high voltage gain

An integrated zero-voltage-switching (ZVS) DC–DC converter with continuous input current and high voltage gain is proposed. The proposed converter can operate with soft switching, a continuous inductor current and fixed switching frequency. The voltage stress of the power switches is relatively low compared to the output voltage. Moreover, soft-switching characteristic of the proposed converter reduces switching loss of active power switches and raise the conversion efficiency. The reverse-recovery problem of output rectifiers is also alleviated by controlling the current changing rates of diodes with the use of the leakage inductance of a coupled inductor. The operation and performance of the proposed DC–DC converter were verified on an 115?W experimental prototype operating at 100?kHz.     

光伏发电与公用电网互补自动切换系统的研究与设计

太阳能光伏发电是开发利用新能源的主要形式之一,但是太阳能发电受日出和日落、晴天和阴天等环境因素影响,存在间歇问题,在阴天和雨天因其发电不足会给生产和生活带来诸多不便。为了充分利用太阳能发电,使其能够与公用电网有效互补,文中设计了一种基于户型光伏发电与公用电网互补自动切换系统。该系统由信号比较和开关控制两部分电路组成。信号比较电路用于检测蓄电池最低工作电压,当检测到蓄电池的输出电压低于最低工作电压,系统就自动切换到公用电网;当检测到蓄电池的输出电压高于或等于最低工作电压时,系统就自动切换到太阳能发电系统。