基于UC3844的反激式开关电源控制环路设计实例

基于UC3844设计了开关电源的控制环路,并阐述了反激式开关电源控制环路的一般设计方法。其过程经实验证明具有较好的通用性,在实际应用中取得了很好的效果。     

一种基于UC3844的多路输出电源设计

阐述了一种基于UC3844 PWM(脉宽调制)控制器的新型多路输出反激式开关电源电路的设计。给出了变压器、漏感消除电路、启动电路以及电压电流反馈电路的设计过程。实验结果表明,该电源性能优良,具有稳压效果好、纹波小、负载调整率高等优点。作为电机控制的电源模块,具有很高的应用价值。     

基于UC3844反激式开关电源的设计

设计了一种基于UC3844的反激式多路输出开关电源,采用工业上常用的DC12~18 V输入,输出2路24 V/300 mA。此开关电源充分利用高频变压器原边绕组特性,把反馈绕组与供电绕组合二为一,简化了外围硬件电路,同时充分考虑了其成本和体积大小,除消除高频杂波用的共模电感、功率电阻、输出整流二极管及滤波电解电容外,其余元器件均采用贴片,最后经实验进一步测试并验证了此开关电源稳定且可靠。     

三相桥式PWM整流电路分析

为了抑制电力电子装置产生的谐波,其中的一种方法就是对整流器本身进行改进,使其尽量不产生谐波。通过对各个电力半导体器件的通断进行PWM调制,使输入电流成为接近正弦且与电源电压同相的PWM波形,从而得到接近1的功率因数。本文主要对电压型三相半桥式PWM整流电路进行分析,在此基础上对PWM整流技术加以探讨,对PWM整流装置的维护和设计有一定参考价值。     

电流型PWM控制芯片TOP412G的原理及应用

TOP412G是三端单片开关式稳压器,它专门用来制作21W以下的隔离式DC/DC变换器。文章详细地介绍了TOP412G控制芯片的工作原理和基于TOP412G控制芯片的反激变换开关稳压电源。     

一种基于UC3842芯片的开关电源设计

信息技术的发展对电源技术提出了更高的要求,从而促进了开关电源技术的发展。开关电源的变换电路形式很多,常用的变换电路有推挽、全桥、半桥、单端正激和单端反激等形式。本文主要介绍了基于芯片UC3842的小功率开关电源系统设计。     

基于UC3842的单端反激式开关电源设计

本文设计了一种基于UC3842芯片控制的双路输出反激式开关电源,介绍了控制电路和变压器设计,由于开关电源设计的实践性较强,本文给出的方法仅作为一种参考,实际问题则需要在实践中不断加以总结和完善,才能满足要求。     

单端反激式开关电源的分析与设计

本文讨论了单端反激式开关电源的两种工作状态:恒压输出状态和恒功率输出状态。推导出两种工作状态下的输出电压表达式,以及工作在恒压状态下所需满足的不等式。最后举例说明三路输出单端反激式开关电源的设计。     

一种数控可调开关电源的设计

文章提出了一种反激式结构的数控开关电源的设计方案,该开关电源采用低成本的控制芯片--UC3842.文中还提出TUC3842在自馈电压变化很大情况下稳定供电的解决方案.此方案电压调节方式(如,RS485总线、USB总线、按键、CAN总线等)多样化,适合使用在工业现场以及实验室.     

电流型PWM控制器UC3844及其在微机电源中的应用

针对电压型脉宽调制器(PWM)控制器只有电压控制环、电流变化滞后电压变化、系统响应速度慢、稳定性差等固有缺点,介绍了既有电压控制环、又有电流控制环的新型电流型PWM控制器.分析了电流型PWM控制器与电压型PWM控制器的控制原理,比较了二者之间的优缺点;介绍了电流型PWM控制器UC3844的工作原理,并应用电流型PWM控制器UC3844设计了微机电源,指出了设计中应该注意的问题.结果表明,由电流型PWM控制器构成的微机电源具有良好的电压调整率、负载调整率和系统稳定性等优点.     

三相电压型PWM整流器的数字化控制

介绍了一种采用TMS320F240DSP芯片的控制方案，该方案基于矢量控制的思想实现了三相电压型PWM整流器的控制，实验证明了该控制方案的可行性。     

三相PWM整流器直接功率控制的仿真研究

基于三相电压型PWM整流器的原理与结构组成,采用电压定向的不定频直接功率控制(VO-DPC),通过对其控制结构的分析,建立其MATLAB/SIMULINK仿真模型.根据仿真结果可以看出,直接功率控制的控制算法简单,而且可以提高整流器的功率因数,有效降低谐波含量.     

基于DSP的三相PWM整流PI调节器设计

通过分析三相脉宽调制（PWM）整流器在a-b-c及d-q旋转坐标系下的数学模型,设计了具有前馈解耦控制的PWM整流器双闭环控制系统。根据系统对电流内环及电压外环的控制要求设计了电流比例积分（PI）调节器及电压PI调节器。最后对整个PWM整流器双闭环控制系统进行仿真,并采用以DSP为核心构建PWM整流器控制系统,仿真和实验结果验证了PI调节器设计的正确性。     

Comprehensive Design of a Three-Phase Three-Switch Buck-Type PWM Rectifier

A three-phase three-switch buck-type pulsewidth modulation rectifier is designed for telecom applications in this paper. The rectifier features a constant 400-V output voltage and 5-kW output power at the three-phase 400-V mains. The principle of operation and the calculation of the relative on-times of the power transistors are described. Based on analytical relationships the stresses of the active and passive components are determined and the accuracy of the given calculations is verified by digital simulations. Exemplarily, a 5-kW power converter is then designed based on the analytical expressions and on switching loss measurements from a hardware prototype constructed with insulated gate bipolar transistor/diode power modules. The loss distribution of the components, the total efficiency, and the junction temperatures of the semiconductors are then evaluated in dependency on the operating point. Finally, the trade-off between the selected switching frequency and the admissible power range for the realized design is shown and a total efficiency of 95.0% is measured on the hardware prototype, where an excellent agreement with the theoretically evaluated efficiency is shown     

一种PWM开关稳压电源中控制电路的设计

开关电源具有线性电源不可比拟的优点,在很多领域得到广泛应用。在讨论PWM开关稳压电源结构的基础上,给出了功率转换电路的设计及主要元件的选型。对UC3875芯片内部结构和功能做了简单介绍,设计了详细的脉宽控制电路,给出了具体电路,并对开关电源本身及其所供给电路进行保护的思路做了进一步探讨。     

A General-Purpose Microprocessor-Based Control Circuit for a Three-Phase Controlled Rectifier Bridge

A novel general-purpose microprocessor-based control circuit for a three-phase controlled rectifier is presented. The performance exhibited by the controller is superior to previously presented circuits. The firing angle is smoothly controlled in the range of 0 to 180/s=deg/ with a fast response and a constant open loop gain, even for the cases where the converter is fed by a weak ac system of unregulated frequency. The synchronization between the line and VCO is implemented by an efficient software-controlled PLL. The effect of source impedance in delaying the synchronization signal has been properly compensated for by the-control circuit. The implementation of the compensation circuit is also presented. The hardware and software control circuit implementation built around an 8086 microprocessor is discussed, and the experimental results are given.     

三相电压型PWM整流器建模与仿真

建立了三相电压型PWM整流器的数学模型,并对其矢量控制策略进行了分析,采用输入电压空间矢量定向,根据参考指令电压矢量直接计算空间电压矢量位置和作用时间,结合直接电流控制的方法进行电流跟踪控制,仿真结果证明了该方案的有效性.     

Control of Three-Phase, Four-Wire PWM Rectifier

This paper presents the analysis, design, and control of a four-wire rectifier system using split-capacitor topology. The proposed controller does not require any complex transformation or input voltage sensing. A detailed analysis of the distortions in the line and the neutral currents is presented. It is shown that the single-carrier-based, conventional sine-triangle PWM (CSPWM) scheme results in a peak-to-peak neutral current ripple, which is greater than the peak-to-peak ripple of any of the line currents. Also, for the same operating condition, the distortions in the line and the neutral currents increase considerably, when a three-limb boost inductor is used instead of three single-phase inductors. A three-carrier-based SPWM scheme is proposed in this paper. Compared to CSPWM, the proposed scheme significantly reduces the neutral current ripple when three single-phase inductors are used, and reduces both line and neutral current ripples when a three-limb inductor is used. The control scheme is verified through Matlab simulation. It is implemented on an field-programmable gate-array (FPGA)-based digital controller and tested on a prototype. Simulation and experimental results are presented.