变速恒频电源闭环控制系统设计

 本文讨论了变速恒频电源闭环控制电路的设计。闭环控制电路的目的除保证变速恒频电源达到所要求的动、静态性能指标外,对其中交交变频器输出中存在的直流、次谐波及其它谐波分量要有强的抑制能力,以减小主电路滤波器的体积重量。为此,文中提出了采用微分反馈并联校正、比例积分串联校正及电压调节的闭环控制系统方案,并进行了一系列实验研究和验证。     

校正开关型电源的功率因数

对于复杂的开关型电源设计者来说,想获得很高的功率因数是比较困难的。如果电源电路的功率因数很低,电源就可能达不到联邦通讯委员会关于电磁容性方面的规定。另外,由于较底的功率因数造成很大的输入尖峰电流:从而降低了电路的可靠性现在,电源设计者应用两种新出现的集成电路,可以较容易地解决这一问题:在应用功率 MOS 管的功率转换电路中,用新型的集成控制电路来校正提高电源的功率因数、并且使电源的输入电压有很宽的调节范围.     

有源功率因数校正技术在脉冲电源设计中的应用

针对节能电火花加工脉冲电源的设计过程中应用了有源功率因数校正技术,电源系统的性能通过工艺试验得到了验证,整个节能电源系统的功率因数提高到0．95。     

基于PSpice的单相Boost功率因数控制器仿真及实现

对以UC1854B为核心组成的有源功率因数校正(APFC)电路进行分析,在PSpice平台基础上建立了UC1854B电压环路、电流环路的数学模型,经仿真模型与实验结果的对比,PF值的误差约为0.1%,畸变总失真THD的误差约为2%,从而验证了仿真模型的正确.采用该控制方式的电路能有效降低电流谐波干扰、降低电源模块的电磁干扰(EMI).     

永磁同步电机电流控制策略比较分析

在电机控制中根据场合要求会采用不同的电流控制策略。对永磁同步电机的4种主要电流控制策略进行了分析并总结了各自的特点。主要针对最大转矩电流比(MTPA)控制、零直轴电流(id=0)控制、单位功率因数(cosφ=1)控制以及恒磁链控制方法,在转矩确定的情况下,对交直轴电流、定子电流及功率因数进行比较分析。按照不同控制方式在MATLAB/Simulink中搭建了仿真模型。4种不同控制方法的仿真试验表明:定子电流幅值从高至低依次为cosφ=1控制、恒磁链控制、id=0控制和MTPA控制；功率因数从高至低依次为cosφ=1控制、恒磁链控制、MTPA控制和id=0控制。最后对比分析了凸极系数不同时4种控制方法的电流和功率因数变化。     

基于SVPWM的高功率因数整流器研究

介绍了三相电压型PWM整流器的数学模型和空间矢量PWM(SVPWM)控制技术,并根据设计要求完成了主电路中相关参数的设计。实验发现,采用SVPWM电流控制技术能够使网侧电压与电流同相位,表明电压型PWM整流器实现了高功率因数整流。     

一种新型交流恒功率负载仿真模型

根据闭环控制的高功率因数(HPF)脉冲宽度调制(PWM)整流器的恒功率工作特性,对交流(AC)恒功率负载(CPL)仿真模型进行了研究。采用输入电流波形跟随电压波形的方法,利用MATLAB建立了交流恒功率负载的仿真模型。在模型两端加载的电压不含谐波和含有谐波的两种情况下,模型均可以自动计算出输入电流有效值(RMS),使得模型输入平均功率保持恒定,并能生成电流波形,反映出电压谐波对电流波形的影响。模型仿真结果与实际高功率因数PWM整流器的输入波形进行了比较,验证了该模型的正确性。     

双通道恒模干扰抑制VHF接收机设计与实现

为了解决民航地空通信受到无线电干扰的问题,提出了双通道恒模干扰抑制自适应抑制接收机的设计实现方案。接收机中的信号处理平台在FPGA中实现自适应干扰抑制,使用DSP判断恒模算法输入信号是否存在干扰,以及对恒模算法输出信号进行属性判断以防止误捕获。再配以具有VHF信号接收功能的射频前端电路,实现接收、干扰抑制、解调地空通信信号的功能。系统测试表明,双通道恒模干扰抑制接收机能够自适应地抑制恒模干扰。     

基于Maxwell 2D的永磁辅助同步磁阻电机的参数化建模及分析

根据永磁辅助同步磁阻电机(PMASRM)复杂的结构特点,基于ANSYS Maxwell 2D软件平台,介绍参数化绘制几何模型的过程,并对结构参数进行优化设计。对恒转矩区间采用最大转矩电流比(MTPA)控制策略、恒功区间采取弱磁控制求解电机电压、电流、内功率因数角、转矩的具体步骤进行了详细说明,为同类电机设计提供了较为实用的分析手段。     

一种新型井下架线电机车供电电源设计

提出了一种新型的基于单周期控制的单位功率因数整流器为井下电机车供电。该电源由维也纳整流级和高频隔离DC-DC变换级两级功率变换器级联构成,但控制电路采用一级协调控制。电路控制简单,不需要乘法器和输入电压检测就可以实现单位功率因数运行,且可以降低开关器件一半的电压应力。详细分析了新型整流电路的基本工作原理和双闭环控制策略,并通过仿真和试验对此新型电路拓扑及其相应控制策略的正确性进行了验证。     

一种新型电解电源设计及其实验研究

从电解电源的高频高效化、绿色化、数字化及智能化的发展方向出发,利用电流增强原理,设计了一种开关管带并联辅助网络的零电压全桥软开关电路拓扑,具有节能增效、可靠性高的优点.采用TMS320LF 2407A为核心控制芯片.得到了全桥移相PWM输出波形,并设计了反馈信号调理电路与后端驱动电路,电路形式简单紧凑,实现了软开关电解电源的全数字化控制.     

Power line transmission and radiation

A power line system consisting of multi-conductors above the ground is decomposed into a metal return (or balanced) and a ground return (unbalanced) circuit in terms of propagation modes. Power line radiation above the ground is sorted into two classes, transition radiation from discontinuities which takes place from a line of finite length and ?erenkov-like radiation from a ground return or unbalanced circuit due to the Earth's finite conductivity and dielectric properties. ?erenkov-like radiation is thought to be predominant and to be a main source origin of power line radiation and, therefore, is specifically discussed in this paper. The problem is reduced simply to wave propagation along an infinite wire above the ground, without taking into account line discontinuities and ionospheric effects. It is shown that a TEM-type wave of a ground return circuit at low frequencies virtually transfers to the principal TM wave of a surface waveguide at high frequencies, via a hybrid EH-type wave in an intermediate range of frequencies, i.e., ‘transition region’ with increasing frequency. Consequently, the attenuation characteristics of wave propagation, which should include radiation losses as well as ohmic losses in the wire and in the ground, possess a maximum and minimum at certain frequencies in the transition region. This is due to two reasons: one is that the Earth transfers to a dielectric from a conductor and the other is that the field concentrates more densely around the wire with increasing frequency. Experimental evidence of this phenomenon is also given.     

Power Electronics in Space: A Review and Projection

Power electronics has emerged as a distinct field of electrical engineering in recent years. This emergence is closely linked with the development of power control and conversion equipment for space application over the last 20 years. Development of switched-mode power conversion techniques has been the dominant activity in this field, spurred by both the improvements in solid-state power devices and the needs of space systems for light weight, highly efficient techniques for dc power regulation. This history is reviewed and projections are made in the four key areas of circuit fundamentals, components, circuit practice, and applications.     

基于集成芯片的同步整流开关电源模块

介绍了DPA—Switch芯片的外部引脚、内部电路及功能模块；讲解了同步整流电路的基本工作原理。根据DPA—Switch的特性给出了同步整流开关电源的设计方法和具体的设计电路，并对外围电路的设计进行了分析，最后给出了测试结果及设计注意事项。     

测控雷达伺服系统整流电路的建模与仿真

电力电子整流电路是测控雷达伺服系统的重要组成部分。某型测控雷达采用了三相零式反并联可逆整流电路结构。分析了整流电路可逆运行的工作原理以及晶闸管触发电路的控制方式,利用MATLAB/Simulink的建模功能,建立了触发脉冲产生电路和整流电路的模型,仿真得出系统可逆运行时电机的工作状态以及整流电路输出电压波形。仿真结果显示,此整流电路可以实现电机的四象限运行,所建模型正确。利用该模型可以对测控雷达伺服系统的分析和设计起到很好的辅助作用。     

Impact Potential of New Power Electronic Technologies

New technological advances in the area of power electronics are having an increasing impact on the design of aerospace control systems. These next generation power components promise improved system performance through increased electronic efficiencies. Applying state-of-the-art packaging concepts as an integral part of the system design will allow these devices to be utilized in a space efficient and reliable manner. The first portion of this paper looks at two such next generation components. The first is a High Voltage Integrated Circuit (HVIC) that provides a bridge between the low voltage controller logic and the high voltage motor winding invertor. This device achieves size reduction and an increase in reliability through integration of low and high voltage logic networks on a single integrated circuit. The second is the Insulated Gate Transistor (IGT). This device provides a high voltage switch with MOS-like drive characteristics. The present and future expectations of these power devices are discussed. This paper then looks at new packaging techniques for power devices. The impact of parasitic circuit effects have significant impact on power circuit performance. Finally, this paper looks at an example control application. The design is that of a permanent magnet motor driven actuator. The drive motor uses 270 vdc for supply voltage. Within the intelligent system controller, is the capability to control the current demands of the motor. The new power electronics devices are making the design feasible in both thermal and volume efficiency. This topic includes projected controller sizing into the 1990s.     

一种小功率逆变电源的设计及实现

介绍了一种小功率逆变电源电路的实现方法。对逆变主电路、电压控制电路、驱动电路、SCOTT电路进行了研究。该逆变电源具有工作可靠、波形失真小的特点。     

高速磁悬浮电动机变频器用开关电源设计

采用基于NCP1200的电流型控制,设计并研制了应用于高速磁悬浮电动机变频器的开关电源,该电源自适应输入电压波动,并自动调节PWM占空比以保证输出电压恒定.实验结果表明,该电源具有输出纹波小、效率高、EMI小、电压调整率和稳压性能好等优点,可用作变频器控制电路的电源.