Self-tuning adaptive feedback linearizing output voltage control for AC/DC converter

This paper presents a cascade output voltage control law adopting the self-tuning adaptive inner and outer-loop controllers for a AC/DC converter modelled as a nonlinear system. The first contribution is to design the inner and outer-loop controllers updating their control gains to enhance the closed-loop performance, estimating unknown parameters. The second one is to show that the proposed inner-loop controller stabilizes not only current error dynamics but also output voltage dynamics viewed as internal dynamics. The effectiveness of proposed method is shown by performing experiments using a 3-kW AC/DC converter.     

一种电流型驱动同步AC/DC反激变流器的设计

提出变频控制新型电流型驱动同步AC/DC反激变流器的设计思路,对电路参数的优化设计及效率进行了详尽的分析,通过实验样机效率分析达到效率要求,验证了电路的实用性,获得了实验结果与理论分析基本一致的结论,同时为AC/DC适配器的设计提供了关键的技术依据.     

电动汽车车载充电器PFC AC/DC变换器设计

为了减少电动汽车接入电网充电时对电网的谐波污染,同时提高电力利用率,必须进行功率因数(PFC)校正。PFC AC/DC作为车载充电器的核心部分之一,可为后级DC/DC系统提供稳定的直流电压。针对功率等级为2 k W的车载充电器,采用升压(Boost)PFC主拓扑结构和基于平均电流控制的AC/DC变换器设计方案,设计了具有PFC的AC/DC变换器,详细给出了其主电路和控制电路的设计流程,包括器件选型、控制策略选择、主电路及控制电路的参数配置。最后通过系统仿真及样机实验测试,验证了系统动态及静态性能。     

基于离散变结构控制的DC/DC变换器

运用趋近律形式的离散变结构控制原理,设计了Buck型DC/DC变换器.设计方法简单,易于实现.通过仿真和实验证实了离散变结构控制具有系统内部参数变化时的鲁棒性,并改善了系统的稳态性能.     

基于六脉波交交变频的闭环调压调速方法研究

针对六脉波交交变频调速技术在高频段存在各频级间转速差较大的问题,提出了一种基于六脉波交交变频的闭环调压调速方法。该方法在2个高频段之间设置多个电压等级,通过改变交交变频输出电压的大小,进行交交变频闭环有级调压调速。仿真和实验结果表明,该方法能够有效利用存储器空间,扩大交交变频调速范围,调速效果较好。     

一种新型的双向DC/DC变换器分析

本文提出了一种新颖的蓄电池充放电系统。选取全桥电路作为主电路拓扑。全桥变换拓扑优点较多,是高质量、大功率变换的主流拓扑。该装置的控制系统采用电压外环电流内环的双闭环控制方式,内环采用峰值电流控制,通过对内环的降阶处理,简化了系统调节器的设计。采用PWM控制方式实现双向DC/DC变换。     

DC/DC 变换器的变结构模糊控制研究

对不同类型的模糊PID控制器(模糊P控制器、模糊PD控制器、模糊PI控制器、模糊PID控制器)在DC/DC变换器中的应用作了全面的研究。目前,模糊PI控制器应用得最为广泛,然而在其控制作用下,DC/DC变换器的输出电压通常会超调,并且当响应时间较短时有很大的冲击电流尖峰。探讨一种变结构模糊控制器,这种控制器将有效地克服模糊PI控制器的上述不足。基于Matlab/Simulink对应用变结构模糊控制器控制的DC/DC变换器系统进行了计算机仿真。仿真结果表明,变结构模糊控制器控制拥有较好的动态特性和稳态性能。     

带跳周期模式的高效升压DC/DC变换器

基于UMC0.6μmBCD工艺设计了一种峰值电流模式的PWM控制升压DC/DC变换器,通过引入跳周期模式实现轻负载下变换器的高效率。仿真结果显示,引入跳周期模式的DC/DC变换器在轻载下(负载电流小于5mA)效率仍达到45%以上。     

交直流并联输电系统的非线性鲁棒控制

针对含有常参数不确定性的交直流输电系统,使用自适应逆推方法设计了直流系统的非线性鲁棒控制器.基于该方法的设计,无需对原系统进行反馈线性化,并能保证闭环误差系统渐近稳定.设计过程表明逆推方法设计的控制器拥有更优越的性能.     

交直流两用仪表不对应性误差分析

从电磁式仪表工作原理出发，分析了其测交直流电流的原理及其引起交直流测量时指示不对应性的现象和原因。     

电动汽车用新型三电平双向DC/DC变换器的研究

提出了一种新型的适用于电动汽车的三电平双向DC/DC变换器,该变换器不仅可以稳定输出电压,同时通过电压控制可以使输出电压跟随给定值在较大范围内连续变化,应用场合比较广泛。详细分析了三电平双向DC/DC变换器的工作原理,介绍了其基本控制策略。仿真验证了此拓扑的正确性和有效性。     

Switching rule for a bidirectional DC/DC converter in an electric vehicle

This paper proposes a switching control strategy (SCS) for a bidirectional DC/DC converter. The aim of this strategy is managing the power that an ultra-capacitor (UC) has to deliver or absorb following a power reference required by the driving cycle ECE-15 of an electric vehicle (EV). For that purpose, the converter is modelled as a switched linear system. Based on hysteresis and logic switching, a switching rule is designed. Necessary and sufficient conditions for the existence of the switching rule are established. Simulation and experimental results of a 1 kW converter are shown to demonstrate the feasibility of this strategy.     

用于电动汽车的多重化软开关双向DC/DC变换器的研究

针对典型的半桥式双向DC/DC变换器拓扑结构特点,利用DCM模式下电感电流反向的特征,采用一种不额外添加半导体器件的软开关技术,减小开关损耗;采用多重化拓扑结构弥补DCM模式下电压、电流纹波大的缺陷;在控制方式上采用电压电流双闭环形式,将共用电压环的输出作为每个基本单元的给定电流,解决了并联结构的均流问题。     

基于ML4841的具有APFC功能的AC/DC变换器设计

AC／DC变换器具有体积小、重量轻、变换效率高等优点，而被广泛地应用到从工业到民用的各个领域。但随之而来的对供电系统的污染的缺点也越来越引起人们的广泛关注，最主要的是由于谐波电流的增加从而使电网的功率因数降低，无功功率增加。本文简要分析了造成这种问题的原因及解决方法，以及采用ML4841构成具有有源功率因数校正功能的AC／DC变换器的设计方法，并给出了典型电路。采用这种电路可使功率因数提高到接近于1。     

Efficient Single-Stage Bridgeless AC to DC Converter Using Grey Wolf Optimization

Bridgeless single-stage converters are used for efficient (alternative current) AC-(direct current) DC conversion. These converters control generators, like electromagnetic meso- and micro-scale generators with low voltage. Power factor correction helps increase the factor of the power supply. The main advantage of the power factor is it shapes the input current for increasing the real power of the AC supply. In this paper, a two-switch bridgeless rectifier topology is designed with a power factor correction capability. For the proposed converter topology to have good power quality parameters, the closed loop scheme, which uses the grey wolf optimization (GWO) algorithm, is implemented. The successes of GWO encourage this research to implement GWO in the topology. The performance of the proposed topology is analyzed under different load conditions. Simulation is carried out using the MATLAB/Simulink environment, and the results are compared with those of conventional (proportional integral derivative) PID and (particle swarm optimization) PSO controllers. To validate the simulation results, a 350-W hardware prototype is implemented, and the voltage ripple, efficiency, and power factor under different load conditions are analyzed and tabulated. The comparative study clearly indicates that the proposed converter topology with a closed loop control scheme using the GWO algorithm improves the power factor to 0.9732 and reduces the voltage ripple to 0.12% with a conversion efficiency of 98.25%.     

Adaptive Nonlinear Control of Induction Motors Through AC/DC/AC Converters

The problem of controlling induction motors, together with associated AC/DC rectifiers and DC/AC inverters, is addressed. The control objectives are threefold: (i) the motor speed should track any reference signal despite mechanical parameter uncertainties and variations; (ii) the DC Link voltage must be tightly regulated; and (iii) the power factor correction (PFC) w.r.t. the power supply net must be performed in a satisfactory way. First, a nonlinear model of the whole controlled system is developed within the Park coordinates. Then, a multi‐loop nonlinear adaptive controller is synthesized using the backstepping design technique. A formal analysis based on Lyapunov stability and average theory is carried out to exhibit the control system performances. In addition to closed‐loop global asymptotic stability, it is proven that all control objectives (motor speed tracking, rotor flux regulation, DC link voltage regulation and unitary power factor) are asymptotically achieved, up to small but unavoidable harmonic errors (ripples).     

燃料电池车载大功率DC/DC变换器的设计与应用

燃料电池的输出特性偏软,电压偏低,难以直接与电动机驱动器匹配,采用DC/DC变换器改善其输出特性,提高输出电压,将燃料电池转换成稳定可控的直流电源,变换器所处的电磁环境较为恶劣,电磁干扰因素居多,采用Motorola(Freescale)16位车用微控制器MC9S12D64作为DC/DC的控制单元,使DC/DC具有良好的抗干扰性能和可靠的运行性能。     

基于六脉波交交变频的分频启动方法研究

在分析六脉波交交变频的基础上及根据软启动中的电压双斜坡启动原理,提出了一种基于六脉波交交变频的分频启动方法。该方法根据交交变频原理和晶闸管触发规律,在电动机启动时,直接在电动机定子侧加电动机启动所需最小转矩所对应的电压值,然后逐级增加变频输出电压值,直至最终所需电压。仿真结果表明,通过合理选择变频输出电压的大小,调节每个等级电压作用的时间,能够有效控制电动机分频启动过程中定子电流的大小,获得良好的转矩变化曲线,改善电动机启动性能。     

基于智能变电站交直流一体化电源系统研究

交直流电源智能化运行是通过整合交、直流电源实现的,为供电用电的一体化提供了解决方案,能有效地提高运行的稳定安全性,从而提高了变电站电源管理能力。而交直流一体化电源系统具有集成度高、管理简便等优势,可集中监控和管理多套电源系统,提高了多套站用电源系统蓄电池组的共享性,随着交直流一体化电源系统方案的广泛应用,其所存在的问题急需从根本上进行解决(包括标准化程度不高、各品牌间的兼容性差等)。为确保变电站的可靠运行,提出全模块化电源系统方案,以期提高维护效率并降低维护成本,为提高交直流一体化电源系统的标准化程度提供参考。