K702开关电源模块应用两例

K702是一块高压DC—AC功率开关模块,尺寸为78×43×9(mm)。该模块内含振荡器、反馈控制器及大功率开关管等,输入电压范围为直流80～260V,自带散热且与内部电路绝缘,不另设散热装置且常温时输出约30W,外加一定散热措施后可输出250W,采取特殊措施后可输出更大功率。本文介绍用该模块制作的应用电路两例,供参考。一、功放专用开关电源一款简洁、高效的功放专用开关电源如图1所示。该电路由输入滤波、整流、DC/AC变换、高频变压器、脉冲整流、滤波和三端稳压器等组成。为降低成本,电路中采用普通元件如压敏电     

程控开关电源并联供电系统的设计与试验

为降低大功率开关电源设计时功率器件的选择、开关频率和功率密度的提高所面临的困难,改善单电源供电的可靠性,设计并制作程控开关电源并联供电系统。系统由2个额定输出功率为16 W的8 V DC/DC模块构成的程控开关电源并联供电系统。以STM32F103微控制器为核心芯片,通过程序控制内部DAC调节PWM主控芯片UC3845的反馈端电压,使DC/DC模块输出电压产生微小变动,进而可调整DC/DC模块的输出电流并实时分配各DC/DC模块的输出电流,软件采用PI算法。试验表明,系统满载效率高于80.23%,电流分配误差最大为1.54%;电源输出在1 s内快速达到稳态;系统以4.5 A为阈值实现过流保护和自恢复功能。     

并联均流高频开关电源的研究

随着分布式电源系统的发展，开关电源并联技术的重要性日益增加。文中介绍了一种新型高频开关电源及220V／10A整流模块的实现方案。其中整流模块采用高可靠性电流型PWM整流器及全桥变换电路来分别实现三相功率因数校正和DC／DC变换，并在模块间采用最大电流自动均流法实现自主均流。     

降压型直流开关稳压电源

本作品采用LM5117作为主控制器产生PWM波控制CSD18532KCSMOS管形成开关电源,经过LC电路滤波、外围降压斩波电路作用以及电压反馈电路的共同作用,最后得到所需的直流稳定电压/电流.本作品具有电压调整率低、负载调整率低、输出噪声纹波电压低以及整机效率较高等优点,并具有过流保护功能.     

一种提高电磁兼容性的智慧路灯控制系统

文中主要研究了一种提高电磁兼容性的智慧路灯控制系统,该系统包括电磁兼容电路、电源电路、电量采集模块、主控模块以及上位机软件等部分。其中：电磁兼容电路包括过流保护电路、过压保护电路、差模滤波电路和共模滤波电路;主控模块由4G通信模块、温湿度检测模块、LED指示灯电路、按键控制电路、蓝牙电路、继电器开关电路及外部输入检测电路等组成,主控模块负责协调和调度各个模块之间的工作;电量检测电路负责检测智慧路灯的工作电压及电流。该系统通过4G通信模块进行无线通信,主控模块与4G通信模块之间采用串口通信,可以节省传输线。     

避免DC-DC电源输出端带大电容满载启动时发生过流保护的方法

DC-DC开关电源在输出端带大电容满载启动时,如果电流检测电路设计不当很容易发生因输出端采取过流保护而不能正常启动的现象.就该问题,本文提出了一种简单的方法,仅增加数个元件就可以避免在输出端带大电容满载起动时出现过流保护,从而保证了DC-DC开关电源即使输出端带大电容也可以实现正常的满载启动.     

单相正弦波逆变电源

本系统实现输入直流电压15V,输出交流电压有效值10V,额定功率10W,交流电压频率在20至100Hz可步进调整。以MSP430单片机为控制核心,产生SPWM波控制全桥电路,然后经过LC滤波电路得到失真度小于0.5%的正弦波。采用PID算法反馈控制使输出交流电压负载调整率低于1%,采用开关电源作为辅助电源、合理选用MOSFET等使系统效率达到90%,采用输入电流前馈法来估计输出电流以实现过流保护以及自恢复功能。     

一种X射线发生装置电流源的设计

目前工业主要用高能电子轰击金属的方法产生X射线。在此设计一种基于开关电源原理的自反馈型直流电流源。该电流源通过DC-DC转换芯片XL4015为开关电源模块提供可调的直流输入电压,Buck型开关电源模块为负载提供稳定的电压,从而流过负载的电流一定。将采样电阻的电压通过OPA2340差分放大,并用SG3525反馈给开关电源模块,从而形成闭环控制。经过试验测试,该电流源输出稳定,精度满足产生X射线的要求,且具有效率高、性能可靠、电路简单易懂、成本低廉等优点。     

一种恒定导通时间的开关电源过流保护电路设计

设计了一种适用于恒定导通时间Buck型DC-DC控制器的过流保护电路。采用两个不同限流门限技术,并对门限进行温度补偿。过流后,利用计数器对开关周期计数,当超过设定值持续过流时,实现门限降低,以达到更低的恒定输出电流。基于0.5μm BiCOMS工艺进行系统仿真验证,达到系统要求。     

TM0165R构成的数字机开关电源原理与检修

TM0165R是深圳天微电子有限公司生产的普通隔离型AC-DC电源芯片,电源电压输出控制方式是电流型脉宽调制(PWM).其内部集成650V耐高压功率开关管、偏置电路、软启动控制电路、电压基准电路及低电压锁定、复位电路,有完善的过压、过流、过载、过温保护,由TM0165R构成的开关电源具有很多优点,如:芯片外围电路设计简单;在待机模式下,通过降低工作频率来降低功耗同时输出稳定的工作电压;在过压或由短路引起的过载等失效模式下,芯片通过内部的保护电路使芯片切换到重启动模式;内部精密电流峰值控制,变压器的尺寸和次级整流二极管可以变得更小,以降低整个系统成本等,因而TM0165R被广泛应用于充电器、适配器、LED照明电源及DVD、DVB机的内置开关电源系统.下面以长虹非常6+1双模接收机开关电源为例,对其原理进行分析.附图为长虹非常6+1双模接收机开关电源电路原理图.     

论直流开关电源节能降耗的工程措施

直流开关电源整流模块效率与输出电流存在直接相关性,目前电源正常工作时模块输出电流远低于额定电流,处于低效率区间。正确配置合理的模块数量、选择或升级具有模块休眠管理功能的监控模块,提高单个整流模块输出电流,提升开关电源实际工作效率,达到节能降耗的目的。     

Modeling and Simulation of Wind Energy Systems with Matrix and Multilevel Power Converters

This paper is concerned with modeling and simulation in Matlab/Simulink of wind energy systems with different topologies for the power converters: matrix converter and multilevel converter. We use pulse modulation by space vector modulation associated with sliding mode for controlling the converters, and we introduce power factor control at the output of the converters. Finally, we present the electric behavior for the power and the current at the input and at the output of the converters.     

一种高精度大功率电镀电源设计

针对传统电镀电源体积大、实现方式复杂以及输出纹波大的特点,提出了一种新型的DC/DC变换器,采用双闭环PWM实时控制方式,具有恒电流和恒电压两种工作方式。用该方法设计了一组9.6 kW电源模块,实验表明,电源输出纹波系数小于1%,效率达到90%。     

High-speed electro-thermal modelling of a three-phase insulated gate bipolar transistor inverter power module

In this article, a high-speed electro-thermal (ET) modelling strategy to predict the junction temperature of insulated gate bipolar transistor (IGBT) devices of a three-phase inverter power module is presented. The temperature-dependent power loss characteristics of IGBT and diode devices are measured and stored in lookup tables, which replace the conventional complicated physics-based compact models. An inverter is modelled as a voltage controlled voltage source, which allows the inverter-based power train simulation to be carried out in the continuous time domain with a large simulation time-step (1 ms). Using the simulated sinusoidal voltage and current components of the inverter output, the given pulse width modulation mode, the conduction time (duty ratio) and the current of the devices are extracted. Based on the lookup tables, on-times and conduction currents of devices, the average power loss over each simulation time-step is calculated, which is then fed into the inverter thermal model to predict the devices' temperatures. The advantage of the proposed model is that an accurate ET simulation of inverter for long real-time (many minutes) operation can be carried out within an acceptable computational time using a standard modern personal computer. Both simulation and experimental validation have been carried out, and an excellent agreement has been achieved between the simulation and experimental data.     

Model constitution of work modes based on high-power laser diode

This paper describes the model constitution and drive circuit design of high-power laser diode (LD), which works in constant current mode, constant power mode and constant voltage mode, based on the electrical characteristics of high power LD. By model constitution and analysis, the relations between the control voltage and the output current are set up, respectively. After an analysis of factors affecting the stability of output current, safety circuits are provided to protect the use of LD.     

大功率T/R组件的研究与设计

现代相控阵雷达系统对探测距离的要求越来越高,这就需要相控阵雷达系统中的关键部件T/R组件提供更大的输出功率,但单个GaAs功率芯片的输出功率的提高较为缓慢。文章介绍了一种通过功率合成的方法来大幅提高单个组件输出功率的设计方法,可将单个组件的输出功率提高到百瓦级,同时通过合理的时序嵌套设计来保证大功率组件的安全工作。将设计结果应用于实际产品,制作出大功率、低噪声的T/R组件,应用于某重点型号雷达系统的研制。     

Design and research of an LED driving circuit with accurate proportional current sampling mode

An LED driving circuit in accurate proportional current sampling mode is designed and fabricated based on CSMC 0.5 μm standard CMOS technology. It realizes accurate sensing of sampling current variation with output driving current. A better constant output current characteristic is achieved by using an amplifier to clamp the drain voltage of both the sampling MOSFET and power MOSFET to the same value with feedback control. Small signal equivalent circuit analysis shows that the small signal output resistance in the accurate proportional current sampling mode circuit is much larger than that in a traditional proportional current sampling mode circuit, and circuit stability could be assured. Circuit simulation and chip testing results show that when the LED driving current is 350 mA and the power supply is 6 V with ±10% variation, the stability of the output constant current of the accurate proportional current sampling mode LED driving 1C will show 41% improvement over that of a traditional proportional current sampling mode LED driving IC.     

大功率半导体激光器驱动电源

根据半导体激光二极管的工作特性，设计了一种以VICOR电源为功率模块，以绝缘栅双极晶体管（IGBT）为大功率变换器件的大功率激光二极管驱动电源，该驱民源电路简单，能有效地抑制电源的浪涌冲击，保证了激光二极管不受外界的电干扰。在线保护机制可实时对半导体激光器工作监控，半导体激光器的慢启动电路、温控电路保证了半导体激光器安全工作。该电源已应用于机载激光雷达样机系统中，通过一年多的使用，半导体激光二极管工作正常，性能稳定可靠。     

基于UCC2897有源正激多路输出电源

随着电力电子技术的飞速发展,各类软开关技术应运而生。文章基于电流控制型芯片UCC2897应用有源箝位技术设计出了一种多路输出的同步整流开关电源。该电源具有过流保护,过压和欠压保护。文中详细介绍了UCC2897的功能和电路设计过程,并采用变压器堆叠绕法和输出比例取样来提高调整率。     

A dual mode charge pump with adaptive output used in a class G audio power amplifier

A dual mode charge pump to produce an adaptive power supply for a class G audio power amplifier is presented.According to the amplitude of the input signals,the charge pump has two level output voltage rails available to save power.It operates both in current mode at high output load and in pulse frequency modulation (PFM) at light load to reduce the power dissipation.Also,dynamic adjustment of the power stage transistor size based on load current at the PFM mode is introduced to reduce the output voltage ripple and prevent the switching frequency from audio range.The prototype is implemented in 0.18μm 3.3 V CMOS technology.Experimental results show that the maximum power efficiency of the charge pump is 79.5%@ 0.5x mode and 83.6%@ lx mode.The output voltage ripple is less than 15 mV while providing 120 mA of the load current at PFM control and less than 18 mV while providing 300 mA of the load current at current mode control.An analytical model for ripple voltage and efficiency calculation of the proposed PFM control demonstrates reasonable agreement with measured results.