三电平PWM整流器双闭环系统的设计与仿真

三电平PWM整流器多采用电压控制外环和电流控制内环组成的双闲环控制系统。电压外环的作用是根据直流电压Udc的大小决定三电平PWM整流器输出功率的大小和方向以及三相电流的给定信号。电流内环的作用是使整流器的实际输入电流能够跟踪电流给定,实现单位功率因数或功率因数可变。文中主要研究了三电平PWM整流器的系统设计,并进行了仿真。结果表明,所设计的双闭环系统具有良好的抗扰动性能,动态响应也得到了明显的改善。     

2kW有源功率因数校正电路设计

有源功率因数校正可减少用电设备对电网的谐波污染,提高电器设备输入端的功率因数。详细分析有源功率因数校正APFC(active power factor corrector)原理,采用平均电流控制模式控制原理,设计一种2 kW有源功率因数校正电路。实验结果表明:以TDA16888为核心的有源功率因数校正器能在90～270 V的宽电压输入范围内得到稳定的380 V直流电压输出,功率因数达0.99,系统性能优越。     

2 kW有源功率因数校正电路设计

有源功率因数校正可减少用电设备对电网的谐波污染,提高电器设备输入端的功率因数.详细分析有源功率因数校正APFC(active power factor corrector)原理,采用平均电流控制模式控制原理,设计一种2 kW有源功率因数校正电路.实验结果表明:以TDA16888为核心的有源功率因数校正器能在90～270V的宽电压输入范围内得到稳定的380V直流电压输出,功率因数达0.99,系统性能优越.     

基于平均电流的功率因数校正电路设计与仿真

为了减少车载充电机功率因数校正电路对公共电网的谐波污染,并保证其向后级电路传送稳定的直流电压,设计了一种以UC3854芯片为核心,采用双闭环控制策略的功率因数校正电路。电流内环控制PWM信号,实现Boost电路输入电压与输入电流的相位相同,电压外环控制实现输出电压的稳定。通过建立功率电路的数学模型,根据传递函数的特点设置了电流内环、电压外环补偿网络的参数。最后通过仿真验证了所有设计参数的正确性,实现了低谐波、低污染和高功率因数的目标。     

基于UCC28019的功率因数校正实验平台设计

基于有源功率因数校准技术,设计了一款高功率因数开关电源实验平台,平台具有自动功率因数校正,结构简单,保护措施完善等优势.平台整体系统设计以德州仪器公司的APFC芯片UCC28019为核心器件,采用电流内环加电压外环的双闭环控制,保证了系统功率因数不低于0.95,采用电流电压互感器采集信号相位,测量并实现功率因数实时显示,同时也可对异常输出进行继电保护.电源系统采用BOOST升压电路,在输出36V/2A额定条件下效率不低于95%,采用良好的闭环反馈电路补偿机制,电压调整率和负载调整率均不高于0.5%.控制核心采用Freescale的MC9S12XS128单片机,完成功率因数测量、电压/电流的动态测量、参数显示、过流保护等功能.测试表明,整体系统运行性能稳定,各项技术指标均达到设计需求.     

中大功率单相功率因数校正器的设计与实现

采用有源功率因数校正技术(active power factor correction,APFC)设计并实现了一款高功率因数、高效率、低谐波、低噪声的"绿色"功率因数校正装置.1700 W样机实验结果表明:所设计的功率因数校正装置能在165～275 V AC宽电压范围内,得到稳定的直流电压输出;输入交流电流能很好的跟踪...     

临界导电模式有源功率因数校正器的设计

为了使临界导电模式功率因数达到0.99以上,在比较3种导电模式优缺点的基础上,讨论一种宽电压输入范围,固定升压输出150 W,工作于临界导电模式的APFC系统的设计方法.它以功率因数控制芯片MC33262为核心,给出实际的设计方案和主要参数的计算结果等.通过实际设计电路的实验结果表明,所设计的有源功率因数校正器能在95～250V的宽电压输入范围内得到非常稳定的400 V直流电压输出,并使功率因数达到要求,总谐波畸变降低至6%.     

一种空调用新型PFC的设计

叙述了功率因数校正的基本原理和常用方法,在传统APFC基础上进一步提出了一种应用于变频空调的新型功率因数校正控制方法.该控制方法的主要特点是可在输入交流电压瞬时值高于输出直流电压值时完全关断开关器件并停止斩渡;只有在输入交流电压瞬时值低于输出直流电压瞬时值时才进行斩波,从而使系统在获得比较满意的功率因数的同时,进一步降低对开关器件的要求,减少系统损耗.     

单相有源功率因数校正电路的设计与仿真研究

论述了单相功率因数校正(APFC)的原理和方法,通过采用Boost型DC-DC变换器作为功率级,UC3854芯片控制PWM的占空比,并直接驱动MOSFET,使输入电流跟踪输入电压,以提高功率因数。根据设计目标要求对1.2kW平均电流控制的单相Boost功率因数校正电路的主电路及UC3854外围电路参数进行了设计和计算,使功率因数达到了0.9984,并在Orcad环境下进行仿真研究,取得了理想的效果。文中的设计方法和思路对于中小功率直流电源的APFC设计具有一定的借鉴作用。     

三相电压型PWM整流器控制新技术的研究

根据电压型PWM整流器在同步旋转dq坐标系中建立的整流器电流控制数学模型,基于电流前馈解耦,解决了有功电流和无功电流互为耦合问题。为克服直流电压响应较慢、抗扰性较差的不足,提出了采用电流内环、基于滑模控制的电压外环电压型PWM整流器的新控制策略。由于采用滑模控制的电压外环,提高了整流器直流电压跟踪和电流跟踪能力,使系统具有响应快、稳定性好、抗负载扰动能力强的优点。文中给出了系统控制器的设计方法。通过正常负载及负载扰动情况下的计算机仿真,证明了新控制策略的可行性。     

光伏并网逆变器的仿真研究

为了提高光伏发电效率和电能质量,对光伏并网逆变器进行了相关研究,针对光伏最大功率点跟踪问题,对传统的电导增量法进行融合和改进．提出一种改进的电导增量控制算法。该控制算法能够快速精准地跟踪最大功率点;有效改善系统在最大功率点附近的震荡现象;提高了光伏电池的发电效率。在逆变控制方面,采用电压外环、电流内环的双PI环控制,电压外环实现中间直流母线电压的稳定控制。电流内环用于控制输出电流的稳定,两者通过中间直流母线耦合,匹配简单,系统控制具有较好的快速性和稳定性;减少了谐波含量,输出电流具有良好的正弦度,且与电网电压同频同相．因而提高了电能质量。最后用matlab对光伏并网逆变器进行建模仿真,实验结果表明该系统工作稳定．性能良好。达到了预定的设计效果。     

Active input-voltage and load-current sharing in input-series and output-parallel connected modular DC-DC converters using dynamic input-voltage reference scheme

This paper explores a new configuration for modular DC/DC converters, namely, series connection at the input, and parallel connection at the output, such that the converters share the input voltage and load current equally. This is an important step toward realizing a truly modular power system architecture, where low-power, low-voltage, building block modules can be connected in any series/parallel combination at input or at output, to realize any given system specifications. A three-loop control scheme, consisting of a common output voltage loop, individual inner current loops, and individual input voltage loops, is proposed to achieve input voltage and load current sharing. The output voltage loop provides the basic reference for inner current loops, which is modified by the respective input voltage loops. The average of converter input voltages, which is dynamically varying, is chosen as the reference for input voltage loops. This choice of reference eliminates interaction among different control loops. The input-series and output-parallel (ISOP) configuration is analyzed using the incremental negative resistance model of DC/DC converters. Based on the analysis, design methods for input voltage controller are developed. Analysis and proposed design methods are verified through simulation, and experimentally, on an ISOP system consisting of two forward converters.     

A Unity Power Factor Correction Preregulator With Fast Dynamic Response Based on a Low-Cost Microcontroller

Low cost passive power factor correction (PFC) and single-stage PFC converters cannot draw a sinusoidal input current and are only suitable solutions to supply low power levels. PFC preregulators based on the use of a multiplier solve such drawbacks, but a second stage dc-dc converter is needed to obtain fast output voltage dynamics. The output voltage response of PFC preregulators can be improved by increasing the corner frequency of the output voltage feedback loop. The main drawback to obtaining a faster converter output response is the distortion of the input current. This paper describes a simple control strategy to obtain a sinusoidal input current. Based on the static analysis of output voltage ripple, a modified sinusoidal reference is created using a low cost microcontroller in order to obtain an input sinusoidal current. This reference replaces the traditional rectified sinusoidal input voltage reference in PFC preregulators with multiplier control. Using this circuitry, PFC preregulator topologies with galvanic isolation are suitable solutions to design a power supply with fast output voltage response (10 or 8.33 ms) and low line current distortion. Finally, theoretical and simulated results are validated using a 500 W prototype.     

基于Sepic和Flyback混合拓扑的辅助电源设计

分析了Sepic和Flyback拓扑结构,根据DC/DC模块电源对辅助电源的需求,提出了Sepic和Flyback混合拓扑的辅助电源,能够输出多路不同幅值电压,并且可以实现各路输出电压之间的隔离。利用状态空间平均法建立了Sepic拓扑的小信号模型,设计了电压和电流双环控制的补偿器,并用Matlab仿真软件进行了分析。该辅助电源应用于一款非隔离的宽范围输入且输出可调的DC/DC模块电源,实现了三路互相隔离的12 V输出电压,一路非隔离的6 V输出电压,输出电压波形稳定,能够满足隔离悬浮供电,也能满足不同芯片对电压范围的要求。     

光伏组网单元直流侧蓄电池储能系统研究

采用了双向半桥Dc/Dc对光伏组网单元直流侧蓄电池进行充放电控制;简单说明了VSI逆变器的结构和原理:分析了双向DC/DC变换器电感电容的选取方法。通过搭建以蓄电池储能为核心的仿真模块,采用功率外环电流内环、电压外环电流内环这两种控制方式,分别在光照强度变化不大以及光照有大幅度跌落这两种情况下进行了仿真分析。仿真结果验证了这两种控制方法在稳定逆变器输出以及直流母线电压的有效性,也体现了功率外环电流内环控制的优越。     

Parallel processing inverter system

A novel method of instantaneous voltage and power balance control of a parallel processing inverter system is proposed. It consists of a high-speed switching PWM (pulsewidth modulated) inverter with an instantaneous current minor loop controller, a voltage major loop controller, and a power balance controller. This system realizes the following functions with only one inverter: constant AC output voltage control with reactive power control, active filtering to absorb load current harmonics, DC voltage and current control as AC-to-DC converter, and uninterruptible power supply (UPS) for stand-alone operation. This system covers a wide application range, including UPS systems, new energy systems, and active filters with voltage control functions     

多单片机直流电源控制板设计

介绍了一种以单片机控制晶闸管触发脉冲为核心的直流电源控制板系统,该系统实现了晶闸管触发脉冲信号的同步产生、移相、驱动以及系统过压／过流保护等功能。用户可通过键盘来设置直流电源的输出,八段数码管显示实际输出电压／电流值;在硬件与软件的配合设计下,该系统实现了智能化三相交流电的相序判断、同步脉冲形成、断线检测、脉冲编码计算、输出数据采样、软启动控制及比例控制等功能。     

基于PSpice的光伏并网系统仿真研究

采用DC／DC和DC／AC两级拓扑结构对光伏并网系统进行了研究和设计,采用改进的定电压跟踪法（CVT）实现最大功率点闭环跟踪,并将PWM控制器引入并网逆变中,采用三角波比较方式实现SPWM电压逆变和输出电流的波形跟踪与控制,在电压、电流内环的基础上引入功率外环以实现系统前后级功率平衡和能量管理,采用基于PSpice的光伏电池仿真模型对所设计光伏并网系统进行了仿真。仿真结果表明,基于PSpice的光伏仿真模型能够有效地模拟实际光伏并网系统的行为特征,将PSpice软件用于光伏发电系统的仿真是可行的。     

A simple control technique for single-SEPIC converter based multiple output SMPS with fully regulated and isolated outputs

Switched mode power supplies (SMPS) with multiple outputs are commonly used for powering up personal computers and many other consumer electronic appliances. Multiple output SMPS circuits normally employ several DC/DC converters for regulating the voltage in each of the outputs. In this paper, a single single ended primary inductance converter (SEPIC) is used to obtain multiple isolated and regulated DC outputs from a single unregulated DC input, so that the reliability and cost effectiveness of the system can be enhanced. Considering that a large number of SMPS are being used in various applications, it is essential to maintain good power quality at the AC mains side of the SMPS circuit adhering to the international standards. Average current control mode has been used in this paper to achieve unity power factor and sinusoidal current at the input side. A novel weighted error approach has been proposed to achieve excellent voltage regulation at all the outputs of the SMPS irrespective of the load variations and input supply fluctuations. The proposed system has been designed and simulated in a PSIM environment and implemented in hardware. The results obtained show an enhanced performance of the power supply in terms of its output voltage regulation and input power quality.     

基于LM5117P的降压型直流开关稳压电源设计

降压型直流开关稳压电源是一种单向DC-DC变换器,实现稳定直流降压功能.本系统采用同步降压控制器LM5117P作为电路控制核心,以同步Buck电路作为降压主电路,通过闭环回路反馈设计以及芯片本身的精准采样,将输入电压16V降为5V恒压输出.