应用于户用储能系统的电池功率自适应下垂控制

以户用储能系统为研究对象,采用下垂控制调节电池功率,即由逆变器控制直流母线,电池的双向DC/DC控制器根据母线电压调节电池功率,该控制方法的优势在于方便实现多直流源并联。双向DC/DC变换器的电路拓扑采用交错式双向Boost变换器,并给出了下垂控制器的具体设计方法。针对系统中普遍存在的因电压采样偏差(逆变器与DC/DC变换器的电压采样是独立的,存在偏差)导致的功率控制偏差问题,提出了两种电池功率自适应控制策略:电压补偿和功率补偿,并给出了具体的实施方法。最后设计了一台5 kW样机,分别实现了两种策略,并进行了对比分析,实验结果验证了所提出策略的有效性。     

降压型变换器的分叉及其混沌行为的研究

针对DC/DC开关变换器存在的非线性混沌现象,利用时间离散映射方法,导出了DC/DC Buck变换器的精确离散模型,研究DC/DC Buck变换器分叉和混沌现象动态演化过程。分析DC/DC Buck变换器的稳定性,最后通过仿真验证了系统的分叉和混沌行为。研究结果表明要使DC/DC Buck变换器工作于稳定状态,可以利用控制电压反馈系数的方法预防和消除分叉及混沌现象的发生。     

基于推挽电路的光伏并网发电微型逆变器研究

随着新能源的逐步推广,光伏并网发电系统得到了发展。其系统通常由多块光伏电池板串联依此提高整个光伏支路电压,通过DC／DC变换器或DC／AC逆变器连接负载或电网。针对以往方式,本文研究了一种由前级推挽正激电路的变换器及后级Dc／Ac逆变器两级联接式的光伏并网发电微型逆变系统。其前级通过光伏电池板最大功率点跟踪进行高频准单极性控制,后级采用流内环,电压外环双闭环控制。仿真研究表明,该系统具有并网电流质量高,动态特性好,最大功率点跟踪精确、效率高、稳定性高等优点。     

一种新型高效率BOOST变换器的设计

文中应用LM3478设计制作了一种新型的DC/DC变换器,对变换器的设计进行了详细分析。测试结果表明,所设计的变换器具有稳定性好,效率高、纹波小等优点,能广泛应用于充电器、汽车电源系统、通信系统中。     

基于DC/DC变换的逆变技术的研究

传统逆变器结构简单、技术成熟,但由于自身拓扑结构的不足使其存在开关损耗大、输出滤波要求高、输出交流幅值受电源电压限制、开关状态转换时可能出现直通短路等缺点。基于Buck的DC/DC变换器由于本身拓扑结构的优势,有效避免了传统逆变器的这些问题,进一步提高了效率。简要介绍了现有基于DC/DC变换器的逆变电路拓扑,并分析了各自拓扑结构的优缺点及相应的控制方式。     

采用脉宽调制控制的谐振型变换器

本文介绍一种采用脉宽调制(PWM)方法稳压的谐振型DC/DC变换器。变换器由两级组成,第一级是用MOS场效应管作开关的升压变换器,由这个开关实现稳定输出电压。第二级是带有整流输出的自激振荡逆变器,在输出整流器的直流边并联一个电容器,此电容器与逆变器变压器的漏感之间满足谐振条件。谐振频率几乎与振荡频率相同,由于谐振现象,减小了晶体管的开关损耗。用由输出至升压变换器的反馈获得良好的稳定度。     

基于TMS320F28XX+UCD8K+HCPL-315J的两级逆变器

介绍以TMS320F28XX、UCD8K和HCPL-315J为核心的单个DSP控制"DC/DC直流变换器 DC/AC逆变器"两级变换逆变器.在介绍整体电路的基础上,详细分析了每个器件的特点及应用.并在500 VA 28 VDC/115 V 400 Hz逆变器样机上进行了实验,验证了设计电路的有效性.     

电动汽车动力电力电子装置的电磁兼容性研究现状

电动汽车动力电力电子装置的电磁兼容性对电动汽车的产业化进程有着重要的影响。动力电力电子装置通常由DC／DC变换器和／或DC／AC逆变器组成。学术上的研究通常主要将精力放在DC／AC逆变器上,针对DC／DC变换器的电磁兼容性研究主要集中在双向变换器12V电源端口的传导干扰方面。介绍了国内外在电动汽车动力电力电子装置的电磁兼容性方面的研究成果。     

小型高效数字式双向DC/DC变换器设计

设计了由STM32F103C8T6单片机控制的基于储能系统的数字式双向DC/DC变换器,不同于传统双向DC/DC变换器中 Buck/Boost模块分离设计的思想,主功率变换电路采用升降压为一体的拓扑结构,减小了变换器体积,采用更适合非线性系统的模糊PID控制方式,减小了输出电压的超调量,增加了系统的安全性,变换器的充放电电流以及系统的工作状态均可由OLED显示,样机测试中,电流波动小,电压稳定性高,应用于试验台LED节能灯,效果良好。     

用于温差发电的程控数字DC/DC变换器设计

半导体温差发电是一种将热能转换成电能的清洁能源发电技术。由于热源温度变化会使温差发电器(TEG)输出电压随之波动,产生的电能不能直接供给用电设备,因此在温差发电系统中引入DC/DC变换器完成电压的转换。针对TEG的工作特性设计了由STM32F334单片机控制的数字DC/DC变换器,进行了硬件系统整体设计和主要参数计算。变换器通过4G网络与One NET云平台进行数据双向实时传输,实现了工作状态的远程监控。样机测试中,恒压模式下输出电压纹波小于50 m V,电流纹波小于40 m A,峰值转换效率高于93%,变换器的云端监控系统操作方便且通信误码率低,为后续分布式温差发电装置的集中控制与管理提供了一定的参考值。     

PWM AC／DC功率双向变流器建模方法的研究（一）

基于脉宽调制（PWM）的AC/DC功率双向变流器作为主要功率变换电路，在许多实际应用的电力电子系统中得到广泛应用，如统一电能质量调节器中的有源电力滤波器系统，交-直-交变频调速系统中的整流或逆变部分，电源系统的逆变器，再生能源并网发电系统中的逆变器以及灵活交流输电系统中的统一潮流控制器等等。在各种应用系统中，人们建立其数学模型进行系统分析和控制设计以满足系统目标。PWM整流器数学模型的研究是PWM整流器及其控制技术研究的基础，本文研究介绍了目前较为流行的四种建模方法，并分别分析其特点及应用。     

Realization of Parasitics in Stability of DC–DC Converters Loaded by Constant Power Loads in Advanced Multiconverter Automotive Systems

Distributed DC power systems are becoming increasingly common in advanced automotive systems. Constant power load (CPL) behavior of tightly regulated DC-DC converters in multiconverter power systems is equivalent to the dynamic negative impedance, destabilizing the DC bus and, consequently, the system. Various techniques have been developed to control ideal/lossless converters loaded by CPLs. Loss components significantly enhance the stability of the cascaded converters. In this paper, the effects of parasitics in the behavior of DC-DC converters loaded by CPLs are investigated. Furthermore, the stability of power converters loaded by CPLs in parallel to conventional constant voltage loads in the presence of loss components is analyzed. Design criteria are presented for converter operation in continuous and discontinuous conduction modes, which gives recommendations on the design of multiconverter DC power systems to avoid negative impedance instability. The proposed stable operation criteria are validated with hardware prototypes and simulation analyses.     

Integrated optimum control of quasi-direct converters

This paper deals with control and design of quasi-direct converters, i.e. AC/AC converters including a forced-commutated rectifier, an inverter, and a small filter in the DC link. Converter performance can be optimized by means of a predictive digital control strategy, which ensures instantaneous input-output power balance, fast response, and high power factor. After a discussion of the control strategy, the paper gives design criteria of both power and control sections. Experimental results of a 2.5-kVA prototype are reported     

新型Buck-Boost逆变器及其控制策略研究

出两个完全相同的独立的buck—boost斩波器,输入并联,输出串联构戚一个DC／AC逆变器,该逆变器实现了单级功率变换,双向功率流,与传统的两级式逆变器相比,具有拓扑结构简单,同时工作的开关元件少,功率密度大,变换效率高等优点。但由于两个斩波器的输出电压要求在较宽范围内变动,故其控制方法和单独的buck-boost斩渡器有所不同,本文对该电路的工作原理和控制方法进行了详细的分析,针对输出电压范围宽的特点,提出了改进的电流控制法,该控制方法采用附加扰动补偿的前馈控制和反馈控制相结合,使两个斩波器的输出电压和逆变器的输出电压都能得到准确的控制,对外界变化能作出快速准确地反应,提高了逆变器对输入电压和负载变化的响应能力。     

A novel three-phase single-stage distributed power inverter

In this paper, a novel three-phase, DC/AC converter suitable for distributed power applications is proposed. The system consists of three DC/DC boost converters with a common point and operating as a three-phase inverter with intrinsic step-up capability. The converter obtained can invert, amplify and, where possible, regenerate bidirectional power sources such as fuel-cells, small gas turbines, and photovoltaic arrays. There are two main advantages to the system: the use of only six insulated gate bipolar transistors and small passive elements, and the fact that it does not need reverse voltage blocking capability. Simulation and experimental results show the effectiveness of the proposed system during both steady-state and dynamic operations.     

牵引变流器

本文介绍了目前高速铁路牵引变流器的情况和存在的问题。提出了采用直流/多交流变换器（这实际是共直流母线的逆变器）代替现有的牵引变流器,并实现以直流牵引网为媒介组成全国统一电网的构想。     

广州换流站交流滤波器投退顺序异常分析及改进措施

直流输电系统运行时需要从交流输电系统吸收容性无功,即对于交流系统而言,换流器总是一种无功负荷。为了补偿无功,通用的做法是在换流站配置无功补偿设备。而交流滤波器作为重要的无功补偿设备,其伴随着系统运行方式的变化进行投退。文中研究了交流滤波器的投退控制,分析了运行中出现的问题。     

A study of active power filters using quad-series voltage-sourcePWM converters for harmonic compensation

An active power filter using quad-series voltage-source pulse-width-modulated (PWM) converters to suppress AC harmonics by injecting compensating currents into the AC system is described. The circuit used to calculate the compensating current references, the compensation characteristics, and the capability of the DC capacitor are discussed theoretically and experimentally. A control circuit for the DC capacitor voltage is proposed. The discussions focus on transient states, based on the instantaneous reactive power theory. A passive LC filter is designed to remove the switching voltage and current ripples caused by the PWM converters at the AC side. Some experimental results that illustrate the details of the study are shown     

A detailed R-L fed bridge converter model for power flow studies inindustrial AC/DC power systems

Because of lower voltage levels and smaller power ratings, the R/X ratio of commutation impedance in industrial AC/DC distribution systems is usually higher than that in HVDC transmission systems. Considerable discrepancies may therefore occur in industrial AC/DC power flow results, especially the reactive power consumption of converters, if the commutation resistances of the converters are neglected. To describe the effects of commutation impedance on converter operations and to precisely relate the fundamental line current and DC output current of the converter, a detailed model of the bridge converter with commutation impedance for use of Newton-Raphson power flow studies in industrial AC/DC power systems is derived in this paper. A coal mine power system and a DC electrified transit railway system with regenerative braking function, a part of Taipei Rapid Transit Systems under planning, have been analyzed to show the improved accuracy and good convergence characteristics of the developed Newton-Raphson power flow formulation with the proposed converter model     

Modified Pulse-Adjustment Technique to Control DC/DC Converters Driving Variable Constant-Power Loads

Multiconverter-distributed DC architectures have been utilized for power distribution in many applications such as telecommunication systems, sea and undersea vehicles, an international space station, aircraft, electric vehicles, hybrid-electric vehicles, and fuel-cell vehicles, where reliability is of prime concern. The number of power-electronic converters (AC/DC, DC/DC, DC/AC, and AC/AC) in these multiconverter electrical power systems varies from a few converters in a conventional land vehicle, to tens of converters in an advanced aircraft, and to hundreds of converters in the international space station. In these advanced applications, power-electronic converters might need to have a tight output-voltage regulation. From the output perspective, this property is highly desirable. However, since power-electronic converters are efficient, tight regulation of the output makes the converter appear as a constant-power load (CPL) at its input side. Dynamic behavior of CPLs is equivalent to negative impedance and, therefore, can result in instability of the interconnected power system. In order to mitigate the instability of the power converters loaded by CPLs, this paper presents the pulse-adjustment digital control technique. It is simple and easy to implement in application-specific integrated circuits, digital-signal processors, or field-programmable gate arrays. Moreover, its dynamic response is fast and robust. Line and load regulations are simply achievable using this technique. Analytical, as well as simulation and experimental results of applying the proposed method to a DC/DC buck-boost converter confirm the validity of the presented technique.