三电平逆变器SVPWM方法仿真

基于三相并网逆变器SPWM及SVPWM控制的仿真研究三相并网逆变器是一种常见的电力电子设备，用于将直流电能转化为交流电能并连接到电网中。

在实际应用中，为了提高逆变器的性能和控制精度，常常采用了SPWM和SVPWM控制策略。

本文对基于三相并网逆变器的SPWM和SVPWM控制进行了仿真研究。

首先，介绍了三相并网逆变器的基本工作原理。

三相并网逆变器由整流器和逆变器两个部分组成。

整流器将电网中的交流电转化为直流电，逆变器将直流电转化为交流电并注入电网中。

同时，逆变器还需要提供电网中的电能质量控制，包括功率因数修正和谐波消除等。

接着，详细介绍了SPWM和SVPWM控制策略。

SPWM控制是一种常见的逆变器控制方法，通过调节逆变器输出电压的幅值和频率来实现对电网的注入电能控制。

SVPWM控制是一种更精确的控制方法，将逆变器输出电压分解为两个三角波信号，并通过调节三角波波形的占空比和相位来精确控制逆变器输出电压。

其优点是能够实现连续变化的电压和频率控制，提高了系统的运行稳定性和效率。

然后，搭建了三相并网逆变器的仿真模型，并分别进行了SPWM和SVPWM控制的仿真实验。

在仿真实验中，选择了逆变器的输出电压波形、频率和相位作为控制目标，通过调节SPWM和SVPWM控制的参数来实现对逆变器输出电压的控制。

仿真结果表明，SVPWM控制相比于SPWM控制具有更高的控制精度和稳定性，在电网注入电能方面效果更好。

最后，对仿真结果进行了分析和讨论。

在仿真实验中，SPWM控制的输出电压存在较大的气动调节误差，而SVPWM控制的输出电压更接近于理想波形，控制精度更高。

此外，SVPWM控制可以实现更高的电压变化速率和更精确的相位控制，更适用于一些对控制精度要求较高的应用场景。

综上所述，基于三相并网逆变器的SPWM和SVPWM控制是一种有效的控制策略。

本文通过仿真研究发现，SVPWM控制相比于SPWM控制具有更高的控制精度和稳定性，可以满足一些对电网注入电能控制要求较高的应用需求。

三电平SVPWM算法研究及仿真三电平SVPWM（Space Vector Pulse Width Modulation）是一种常见的电力电子转换技术，用于控制三相逆变器或变频器输出的电压波形。

本文将着重研究三电平SVPWM算法，并进行仿真评估。

首先，我们来介绍三电平SVPWM算法的原理。

它基于矢量控制（Vector Control）理论，通过在三相逆变器的输出电压空间矢量图上选择合适的电压矢量，以实现所需的输出电压。

1.获取输入信号：通过采样电网电压和电网电流，获取输入信号的相位和幅值。

2.电网电压矢量合成：将电网电压坐标变换到α-β坐标系，然后将三相电压矢量转换为α-β坐标系下的矢量。

3. 电机电流转换：通过坐标变换将α-β坐标系下的矢量转换为dq 坐标系下的矢量，其中d轴是电机电流的直流分量，q轴是电机电流的交流分量。

4. 电机电流控制：通过PI控制器对dq坐标系下的电机电流进行控制，以实现所需的电机电流。

5.电网电压生成：通过逆变器控制器生成电网输出电压的矢量。

6.SVM模块选择：根据电网电压矢量在α-β坐标系下的位置，选择合适的SVM模块进行控制。

7.输出PWM波形：根据选择的SVM模块，将PWM波形通过逆变器输出到电网上。

接下来，我们将进行三电平SVPWM的仿真评估。

仿真环境可以使用Matlab/Simulink或者PSCAD等软件。

首先，我们需要建立三电平逆变器的模型，包括电网电压、逆变器、电机等组成部分。

然后，编写三电平SVPWM算法的仿真程序。

在仿真程序中，通过输入电网电压和电机负载等参数，我们可以模拟电网电压和电机电流的变化情况。

然后，根据三电平SVPWM算法，计算逆变器输出的PWM波形，并将其作为输入给逆变器，从而实现对电网电压和电机电流的控制。

最后，通过仿真结果分析三电平SVPWM算法的性能，包括输出波形的失真程度、功率因数、谐波含量等。

并与传统的两电平SVPWM算法进行对比，评估其性能优势。

摘要近年来，三电平逆变器在大容量、高压的场合得到了越来越多的应用。

在其众多的控制策略中，SVPWM算法具有调制比大、能够优化输出电压波形、易于数字实现、母线电压利用率高等优点。

本文首先对三电平逆变器技术的发展状况进行了综述，分析了三电平逆变器的几种拓扑结构，控制策略以及各自的优缺点。

其次，以二极管箝位式三电平逆变器为基础，阐述了三电平逆变器的工作原理、数学模型，分析了空间电压矢量控制策略的原理，对三电平逆变器空间电压矢量的控制算法进行了改进，引进了大扇区和小三角形的判断方法，给出了扇区和小三角形区域的判断规则、合成参考电压矢量的相应输出电压矢量作用时间和作用顺序以及开关信号的产生方法。

最后，采用MATLAB/Simulink进行仿真分析，一个一个模块的搭建仿真模块，然后把各个模块连接起来，实现了对三电平逆变器的SVPWM控制算法的仿真，观察系统的输出波形，分析波形，并进行比较，验证了算法的可行性。

关键词：三电平逆变器空间电压矢量控制（SVPWM） MATLAB仿真ABSTRACTRecently, three-level inverter in the large capacity and high pressure situation got more and more applications fields. Among many of modulation strategies, SVPWM has been one of the most popular research points. The main advantages of the strategy are the following: it provides larger under modulation range and offers significant flexibility to optimize switching waveforms, it is well suited for implementation on a digital computer, it has higher DC voltage utilization ratio. Initially, summing up the development condition of three-level inverter technology, analyzed the structure of three-level inverter topological, the control strategy and their respective advantages and disadvantages.Secondly, the paper based on the ground-clam -p diode type three-level inverter, expounds the work principle of three-level inverter, and analyzes the principle of the SVPWM. By improving the three-level inverter SVPWM control algorithm, this paper introduces the estimation method of the big sectors and the small triangles, and proposes the judgment rules for large sector and triangle region and puts forward the corresponding output sequence of the synthesis reference voltage vector and optimizes the function sequence of switch vector.Finally ,using MATLAB/SIMULINK to carry on the simulation analysis. Building the simulation system model to realized to three-level inverter SVPWM control algorithm, and to confirmed the algorithm feasibility.Keywords:Three-level inverter; space voltage vector control (SVPWM); MATLAB simulation目录摘要 (I)ABSTRACT (II)1 绪论 (1)1.1 课题目的及意义 (1)1.2 国内外研究现状 (1)1.2.1 拓扑结构 (2)1.2.2 控制策略 (5)1.3 课题任务要求 (6)1.4课题重点内容 (6)2 三电平逆变器的原理 (7)2.1二极管箝位型三电平逆变器 (8)2.1.1二极管箝位型逆变电路的工作原理 (8)2.1.1 二极管箝位型逆变电路的控制要求 (11)2.1.2 三电平逆变器的数学模型 (11)2.2 三电平SVPWM控制技术 (14)2.2.1三相静止坐标系到两相静止坐标系的变换 (14)2.2.1 SVPWM控制原理 (16)3 三电平SVPWM算法研究 (19)3.1 参考矢量的位置判断 (19)3.1.1 扇区判断 (19)3.1.2 小三角形的判断 (20)3.2 输出矢量的确定 (21)3.3计算各个矢量的作用时间 (21)3.4 空间电压矢量作用顺序 (23)4 三电平逆变器的MATLAB仿真 (26)4.2 扇区的判断 (27)4.3 小三角形判断 (28)4.4 时间计算 (29)4.5 矢量的作用顺序 (29)4.5.1七段式SVPWM时间分配 (29)4.5.2矢量状态次序 (29)4.6 矢量状态到开关状态 (33)5 三电平逆变器的仿真结果分析 (35)总结 (46)参考文献 (48)致谢 (49)1 绪论1.1 课题目的及意义从20世纪90年代以来，以高压IGBT、IGCT为代表的性能优异的复合器件的发展受人关注，并在此基础上产生了很多新型的高压大容量变换拓扑结构。

411/2008收稿日期：2007-10-05作者简介：胡慧慧(1980-)，女，硕士研究生，主要研究方向为电力电子与电力传动技术；马文忠(1968-)，男，副教授，博士，主要研究方向为电力电子变换与电机驱动技术。

基于SVPWM 的三电平逆变器仿真研究胡慧慧，马文忠，董磊（中国石油大学（华东）信息与控制工程学院，山东东营257061）摘 要：分析三电平逆变器的结构及工作原理，研究将电压空间矢量控制技术（SVPWM ）应用在三电平逆变器上的方法，并通过仿真，验证算法的可行性。

关键词：三电平；矢量控制；逆变器；仿真中图分类号：TM464文献标识码：A文章编号：1671-8410(2008)01-0041-04Simulation and Research of Three-level Inverter with SVPWMHU Hui-hui, MA Wen-zhong, DONG Lei(College of Information and Control Engineering, China University of Petroleum, Dongying, Shandong 257061, China)Abstract: This paper analyzes the structure and operation principle of three-level inverter and researches space vector PWM(SVPWM)control technique. The reliability of the system was estimated by simulation of the mathematical model.Key words:three-level; space vector control; inverter; simulation0引言与传统的逆变器相比，目前以二极管中点箝位型结构为代表的三电平逆变器更适合用于控制高电压、大功率电机，且具备输出电压波形谐波含量低，跳变（d u /d t ）引起的电磁干扰小等优点。

SVPWM算法控制三电平逆变器仿真
田玉超;刘勇;丛望
【期刊名称】《应用科技》
【年(卷),期】2005(032)002
【摘要】三电平逆变器是目前电力电子与电力传动学科研究的热点之一,但其控制算法也要比传统的两电平逆变器复杂得多,一般采用便于数字实现的空间矢量脉宽调制(SVPWM)的方法来控制.介绍了SVPWM算法控制三电平逆变器的实现方法和具体步骤,最后给出了用MATLAB/Simulink仿真的结果,表明了三电平逆变器的优点,同时对于深入理解算法原理和控制过程也具有一定的参考价值.
【总页数】3页(P37-39)
【作者】田玉超;刘勇;丛望
【作者单位】哈尔滨工程大学,自动化学院,黑龙江,哈尔滨,150001;哈尔滨工程大学,自动化学院,黑龙江,哈尔滨,150001;哈尔滨工程大学,自动化学院,黑龙江,哈尔滨,150001
【正文语种】中文
【中图分类】TM464
【相关文献】
1.三电平逆变器简化 SVPWM算法仿真与实现 [J], 刘成友;周鑫;张华伟;徐路钊;蒋红兵;秦航
2.NPC型三电平逆变器SVPWM控制研究与仿真 [J], 肖潇;宋平岗;喻冲
3.NPC三电平逆变器SVPWM算法的研究及仿真实现 [J], 朱希荣;周晓锋;周渊深
4.三电平逆变器SVPWM算法的研究及仿真 [J], 黄珊珊
5.三电平逆变器SVPWM控制算法及其仿真研究 [J], 张毅;许月霞
因版权原因，仅展示原文概要，查看原文内容请购买。

基于SVPWM三相并网逆变器仿真报告目录1. SVPWM逆变器简介 (1)2. SVPWM逆变器基本原理 (2)2.1. SVPWM调制技术原理 (2)2.2. SVPWM算法实现 (5)3. SVPWM逆变器开环模型 (11)3.1. SVPWM逆变器开环模型建立 (11)3.2. SVPWM逆变器开环模型仿真分析 (14)4. SVPWM逆变器闭环模型 (16)4.1. SVPWM逆变器闭环模型建立 (16)4.2. SVPWM逆变器闭环模型仿真分析 (17)1.SVPWM逆变器简介三电平及多电平空间矢量调制(Space Vector Pulse Width Modulation，SVPWM)法是建立在空间矢量合成概念上的PWM方法。

它以三相正弦交流参考电压用一个旋转的电压矢量来代替，通过这个矢量所在位置附近三个相邻变换器的开关状态矢量，利用伏秒平衡原理对其拟和形成PWM波形。

空间矢量调制方法在大范围调制比内有很好的性能，具有很小的输出谐波含量和较高的电压利用率。

而且这种方法对各种目标的控制相对容易实现。

SVPWM技术源于三相电机调速控制系统。

随着数字化控制手段的发展，在UPS/EPS、变频器等各类三相PWM逆变电源中得到了广泛的应用。

与其他传统PWM技术相比，SVPWM技术有着母线电压利用率高、易于数字化实现、算法灵活便于实现各种优化PWM技术等众多优点。

2. SVPWM 逆变器基本原理2.1. SVPWM 调制技术原理SVPWM 的理论基础是平均值等效原理，即在一个开关周期内通过对基本电压矢量加以组合，使其平均值与给定电压矢量相等。

在某个时刻，电压矢量旋转到某个区域中，可由组成这个区域的两个相邻的非零矢量和零矢量在时间上的不同组合来得到。

两个矢量的作用时间可以一次施加，也可以在一个采样周期内分多次施加，这样通过控制各个电压矢量的作用时间，使电压空间矢量接近按圆轨迹旋转，就可以使逆变器输出近似正弦波电压。

电力电子建模仿真报告
一、仿真要求
设计一个三相SPWM逆变器，使得输出相电压100Hz，有效值220V，负载RL类型（R=50Ω，L=10mH）直流母线电压540V，观察输出电流波形，对电流电压进行谐波分析。

二、仿真模型
图1 SPWM三相逆变电路仿真模型
三、仿真分析
设置参数，即将调制波频率设为100Hz，载波频率设为基波的30倍（载波比N=30），即3000Hz，m=0.9，负载RL类型（R=50Ω，L=10mH），直流母线电压540V，在powergui 中设置为离散仿真模式，采样时间设为1e-006s，运行仿真模型。

双击powergui，选择FFT 分析。

图2 SPWM三相逆变电路输出A相电流a I的波形
图3 SPWM三相逆变电路输出A相电流a I的FFT分析
U的波形图4 SPWM三相逆变电路输出A相电流a
U的FFT分析
图5 SPWM三相逆变电路输出A相电流a
由上面分析可知，电流谐波分布中最高的为28次谐波，最高频率为3000Hz时的THD=12.63%，输出电流近似为正弦波。

电压谐波分布中最高的为28次谐波，最高频率为3000Hz时的THD=79.22%。

四、仿真总结
通过适当的参数设置（如载波比N、调制度m等），运用SPWM控制技术，可以有效减小输出电压和输出电流的谐波分量，改善输出波形，可以很好的实现逆变电路的运行要求。

基于SVPWM三相并网逆变器仿真报告目录1.SVPWM逆变器简介 (1)2.SVPWM逆变器基本原理 (2)2.1.SVPWM调制技术原理 (2)2.2.SVPWM算法实现 (5)3.SVPWM逆变器开环模型 (9)3.1.SVPWM逆变器开环模型建立 (9)3.2.SVPWM逆变器开环模型仿真分析 (12)4.SVPWM逆变器闭环模型 (14)4.1.SVPWM逆变器闭环模型建立 (14)4.2.SVPWM逆变器闭环模型仿真分析 (15)1.SVPWM逆变器简介三电平及多电平空间矢量调制(Space Vector Pulse Width Modulation ,SVPWM)法是建立在空间矢量合成概念上的PWM方法。

它以三相正弦交流参考电压用一个旋转的电压矢量来代替,通过这个矢量所在位置附近三个相邻变换器的开关状态矢量,利用伏秒平衡原理对其拟和形成PWM波形。

空间矢量调制方法在大范围调制比内有很好的性能,具有很小的输出谐波含量和较高的电压利用率。

而且这种方法对各种目标的控制相对容易实现。

SVPWM技术源于三相电机调速控制系统。

随着数字化控制手段的发展,在UPS/EPS、变频器等各类三相PWM逆变电源中得到了广泛的应用。

与其他传统PWM技术相比,SVPWM技术有着母线电压利用率高、易于数字化实现、算法灵活便于实现各种优化PWM技术等众多优点。

2. SVPWM 逆变器基本原理2.1. SVPWM 调制技术原理SVPWM 的理论基础是平均值等效原理 ,即在一个开关周期内通过对基本电压矢量加以组合 ,使其平均值与给定电压矢量相等。

在某个时刻 ,电压矢量旋转到某个区域中 ,可由组成这个区域的两个相邻的非零矢量和零矢量在时间上的不同组合来得到。

两个矢量的作用时间可以一次施加 ,也可以在一个采样周期内分多次施加 ,这样通过控制各个电压矢量的作用时间 ,使电压空间矢量接近按圆轨迹旋转 ,就可以使逆变器输出近似正弦波电压。

三电平逆变器简化 SVPWM算法仿真与实现刘成友;周鑫;张华伟;徐路钊;蒋红兵;秦航【摘要】为了简化三电平逆变器控制算法、提高系统稳定性，提出通过交替使用不同空间电压矢量以实现磁链跟踪控制的二极管箝位型三电平逆变器 SVPWM控制算法。

依据 Matlab ／Simulink 的仿真结果，进行以 TMS320F2812 DSP 为控制核心的三电平逆变器整机试验。

结果表明，SVPWM算法简单，易于掌握，二极管箝位型三电平逆变器输出电压经滤波后十分接近正弦波，且系统稳定性较高，能够较好地满足工程需要。

%In order to simplify the control algorithm of three level inverter and improve the stability of the system,diode clamped three level inverter SVPWM control algorithm was put forward which based on the change of the space voltage vector to realize magnetic chain tracking control.By Matlab /Simulink simulat-tion output,the machine testing was made with TMS320F2812 DSP as the control core of diode clamped three level inverter.The results showed that SVPWM algorithm was simple and easy to master,the output voltage of diode clamped three level inverter was close to sine wave,the system had better stability to better meet the needs of engineering.【期刊名称】《郑州轻工业学院学报（自然科学版）》【年(卷),期】2015(000)005【总页数】4页(P117-120)【关键词】三电平逆变器;SVPWM算法;Matlab /Simulink 系统仿真【作者】刘成友;周鑫;张华伟;徐路钊;蒋红兵;秦航【作者单位】南京医科大学附属南京医院医疗设备处，江苏南京 210006;南京医科大学附属南京医院医疗设备处，江苏南京 210006;南京医科大学附属南京医院医疗设备处，江苏南京 210006;南京医科大学附属南京医院医疗设备处，江苏南京 210006;南京医科大学附属南京医院医疗设备处，江苏南京 210006;南京医科大学附属南京医院医疗设备处，江苏南京 210006【正文语种】中文【中图分类】TM464现代科技日新月异，人们在体验现代科技带来便利的同时，也加剧了对其的依赖性.电力能源是近现代科技的推动力，人类对电能的依赖程度尤为突出.逆变器是一种电能转换和优化的电气装置，现已被广泛地应用于家电、汽车、轧钢、油田和医疗卫生系统中[1].然而，随着高压大功率电力电子装置的发展，逆变器从最初的两电平向三电平以上的多电平持续发展[2].三电平逆变器是多电平逆变器中结构最简单、使用最广泛的一种电路，相对于传统的两电平逆变器，三电平逆变器主要优点在于：开关管承受电压小，仅为直流母线电压的一半；逆变器输出端电流谐波含量低；器件具有很强的正向阻断电压能力；系统损耗小、转换效率高等[3].虽然三电平逆变器在技术上已较为成熟，但仍存在不少问题，如控制算法较为复杂、中点电压平衡难以控制、高压环境中系统稳定性较差等[4].鉴于此，本文拟通过分析传统三电平逆变器控制方法，研究二极管箝位型三电平逆变器PWM控制方法，以及三电平SVPWM控制策略，提出SVPWM 新算法，据此设计三电平逆变器硬件电路；使用交互式仿真软件Matlab/Simulink对系统进行仿真，以验证SVPWM新算法的正确性和有效性.1.1 工作原理对于两电平逆变器，每个桥臂只能输出非正即负的电平，而三电平逆变器除了能够输出正负电平外，还可以输出零电平.本文主要研究二极管箝位型三电平逆变器的输出特性，其工作原理见图1.从图1可知，在二极管箝位型三电平逆变器中每一项均含有4个续流二极管、4个开关器件、2个篏位二极管，且每项输出端均含有3种工作状态，即“0”状态(零电平状态)、“1”状态(正电平状态)、“-1”状态(负电平状态).以A相为例，A 相输出与相关开关状态关系见表1.值得注意的是，逆变器A相输出可在状态间变化，正电平状态和负电平状态需经零电平状态过渡.1.2 逆变器等效模型在理想状态下，逆变器电路每相臂电路可等效为一个与直流侧相同的三掷开关.根据三电平逆变器的定义可以将原理图结构简化(见图2).为简化模型，本文定义Va,Vb,Vc分别为三相电输出状态的取值(0,1,-1)，则有对于负载段有整理得1.3 三电平逆变器SVPWM算法设计SVPWM是一种交替使用不同空间电压矢量以实现磁链跟踪的控制方法，通过建立在空间电压矢量合成概念上的脉宽调制方法，以实现高质量波形输出.研究表明，三相静止电压可在(a,b,c)坐标系与两相静止坐标系(α,β)之间相互转换[5]，电压空间矢量变换形式如下：由公式①知，公式②可化简为把等效三通开关(Va,Vb,Vc)的3×3×3种状态带入公式③，并在(α,β)坐标系描绘各电压空间矢量的投影，结果如图3所示.由图3可知，三电平逆变器有27个基本矢量可供选择，但实际上仅有19个有效基本矢量，其中有1个零矢量位于原点，记作V0；6个小矢量位于小六边形的6个顶点，记作V1—V6；6个中矢量位于大六边形的6边中点，记作V7—V12；有6个大矢量位于大六边形的6个顶点，记作V13—V18.由经典SVPWM控制理论可知，大区域按照矢量角度每60°划分为一个区，则对于I区(图3中(0,0,0),(1,-1,-1),(1,1,-1)组成的区域)，采用中心对称七段式SVPWM波形将基本作用时间分配给矢量状态，扇区判断、计算各个矢量的作用时间，结合DSA数字信号处理窗函数或矩形序列函数，以I区第一小区为例，则式③可整理为其中,RN(t-n)表示向七段中心平移的窗函数，其他区域空间矢量与式④类似，唯一需要改变的为N值大小，式④即为SVPWM优化控制策略.本文完成二极管箝位型三电平逆变器系统参数设计后，利用Matlab中的Simulink电力电子模块建立三电平逆变器模型，并进行仿真；在此基础上以TMS320F2812 DSP为系统控制核心，用IRFP450 MOS系列开关器件进行电路设计，用泰克TDS1000B数字示波器显示整机试验波形.2.1 Matlab系统仿真仿真参数设置如下：直流母线输入电压550 V，调制比为0.888 89，开关频率为2 000 Hz，载波频率为50 Hz，负载采用三相对称负载，电阻为100 Ω，电容为47 μF，电感为20 mH.对三电平逆变器 SVPWM 控制方法下的50 Hz输出特性进行研究，仿真结果如图4—6所示.由图4—6可知,二极管箝位型三电平逆变器可以较稳定地输出50 Hz电压和负载电流，在频率上能够满足工程需要；负载电压输出波形轮廓接近正弦波或三角波，输出电压呈现阶跃跳变，各组成成分较稳定；纯电阻负载仿真波形和电压仿真波形相似，电容对高频电流滤波作用较小，纯电容负载仿真波形和纯电阻负载仿真波形相似，不再赘述；从图5—6可以看出，以纯电感、电阻电感或电容电感作为输出端负载时，电流仿真波形十分接近正弦波(R2=0.999)，这是由于电感具有滤波作用，但还是含有较少的高次谐波.2.2 整机试验如前所述，在系统仿真的基础上，使用TMS320F2812 DSP作为系统控制核心设计二极管箝位型三电平逆变器，同样采用550 V直流电压输入，使用阻值为100 Ω和500 Ω的线圈式滑动变阻器，电容为47 μF，电感为20 mH用作负载，并使用数字示波器显示试验结果，波形如图7—10所示.图7—10为系统整机试验实际测量值，从中可以看出，整机试验与系统仿真结果相似，但整机试验测量曲线较为粗糙，在波峰波谷上有较明显的“毛刺”，其原因可能是外界噪声干扰、高次谐波叠加影响、IRFP450 MOS系列开关器件反应时间间隔，以及其他电子器件非理想化的干扰所致.随着时间的延续，图7和图8显示输出波形趋于平稳.图9为经过电阻电感电路滤波后的电流波形，三相电平电压趋于相等，且各波形相位差接近120°，相位差为(120±1.23)°.图10为改变负载电阻电感大小时的电流图，由图可见：当电阻电感负载增大时，电流幅值减小，相位不变;当电阻电感负载减少时，电流幅值增大，相位不变，符合工程要求；在电阻电感负载大小变化瞬间，输出电流幅值波动较大，之后趋于稳定.以上各图电流/电压频率均为50 Hz，可满足工程需要.本文通过分析二极管箝位型三电平逆变器的组成及工作原理，提出了易于掌握和实现的简化SVPWM算法，并基于该算法使用Matlab/Simulink对二极管箝位型三电平逆变器进行了仿真实验.同时根据仿真结果,以TMS320F2812 DSP为控制核心,进行了二极管箝位型三电平逆变器整机试验.试验结果显示：三电平逆变器的输出电压经滤波后波形近似于正弦波，能够较好地满足工程需要.【相关文献】[1] 马兰珍,王明渝,徐四勤,等.新型多电平光伏并网逆变器控制策略研究[J].电力系统保护与控制，2012(17):72.[2] 何湘宁,吴岩松,杨兵建,等.大功率三电平逆变器的开关模态转换状态的实时监测[J].中国电机工程学报，2012(30):54.[3] 李明,易灵芝,彭寒梅,等.光伏并网逆变器的三环控制策略研究[J].电力系统保护与控制，2010(19):46.[4] 尹成俊,江明.基于TMS320LF2407A的SVPWM的研究实现[J].自动化仪器与仪表,2009,27(1):12.[5] 胡应占,郭素娜.适用于电网不平衡时的广义积分器锁相环设计[J].电力系统保护与控制,2014(11):148.。

Review of High-Performance Three-Phase Power-Factor Correction Circuits Hengchun Mao,Member,IEEE,Fred C.Y.Lee,Fellow,IEEE,Dushan Boroyevich,Member,IEEE,and Silva Hiti,Member,IEEEAbstract—This paper reviews recent progress in topology, control,and design aspects in three-phase power-factor correction (PFC)techniques.Different switching rectifier topologies are presented for various applications.Representative soft-switching schemes,including zero-voltage and zero-current switched pulsewidth modulated(PWM)techniques,are investigated. Merits and limitations of these techniques are discussed and illustrated by experimental results obtained on prototype converters.Control and inputfilter design issues are also discussed.Index Terms—Power factor correction,soft switching,three-phase converters.I.I NTRODUCTIONM OTIV ATED by the forthcoming stringent power-quality regulations,power-factor correction(PFC)has been an active research topic in power electronics.The single-phase PFC is already a common practice,and the industrial application of three-phase PFC techniques has also emerged. Up to this point,the research of three-phase converters has been heavily focused on inverter applications.Although most techniques developed in the inverter area can be used in PFC applications,a PFC circuit has its unique characteristics and,therefore,deserves some special treatment.The primary differences between PFC and inverter applications include the following aspects.•Special attention has to be paid to the quality of input current to reduce the pollution to the utility,usually measured by the input current total harmonic distortion (THD).Although there are no specific limits on the input current distortion of general high-power three-phase converters at present,it is a common practice to limit the input current THD of three-phase PFC converters at least below10%.This makes control design more critical than in inverters.Manuscript received November5,1996;revised March3,1997.H.Mao was with the Virginia Power Electronics Center,Bradley De-partment of Electrical Engineering,Virginia Polytechnic Institute and State University,Blacksburg,V A24061-0111USA.He is now with Bell Labora-tories,Lucent Technologies,Mesquite,TX75149USA.F.C.Y.Lee and D.Boroyevich are with the Virginia Power Electronics Center,Bradley Department of Electrical Engineering,Virginia Polytechnic Institute and State University,Blacksburg,V A24061-0111USA.S.Hiti was with the Virginia Power Electronics Center,Bradley Department of Electrical Engineering,Virginia Polytechnic Institute and State University, Blacksburg,V A24061-0111USA.She is now with Delco Electronics—Power Control Systems,Torrance,CA90509-2923USA.Publisher Item Identifier S0278-0046(97)05260-X.•The electromagnetic interference(EMI)emissions are a great concern in PFC applications.The high-speed switch-ing action of a PFC converter generates both differential-mode and common-mode noises at the input of the PFC converter at high frequencies.Passivefiltering is widely used to reduce the EMI emissions into the utility.•High switching frequencies are desirable to reduce the size and weight of reactive components(especially in-ductors)and to improve current-control performance.While a20-kHz switching frequency is deemed sufficient in most inverter applications,a PFC converter prefersa much higher switching frequency,e.g.,50–100kHzin tens of kilowatt power level.The effect of soft-switching techniques is,therefore,very prominent in PFC applications.•The input currents are generally in phase with the input voltages,and bidirectional powerflow is usually not required in PFC circuits.These facts provide someflex-ibility to develop soft-switching techniques and control schemes specific to PFC converters.Soft-switching techniques shape the switch voltage or cur-rent waveforms in the switching transients to create a favor-able switching condition.Therefore,the switching losses of switchesandvarious quasi-resonant dc-link or parallel dc-link converters [12]–[14]share the same basic concept with ZVT techniques. Many three-phase topologies also explicitly utilize the ZVT or ZCT principle[1],[5],[8],[15],[17]–[19].The RC, QRC,and MRC achieve soft-switching function by creating piecewise-sinusoidal voltage/current waveforms in a resonant fashion and suffer from high circulating energy,high switch voltage/current rating,variable switching frequencies,and complex control requirements.The QSW tries to reduce the circulating energy of QRC’s by blocking part of the resonance with additional switches,but still has the shortcoming of high switch voltage stress.On the other hand,the soft-transition techniques modify the converter operation only in a short period during switching transitions and allow the converter to be controlled with constant-frequency PWM.A soft-transition converter has similar voltage/current stresses and circulating energy,as in its PWM counterpart.Since three-phase PFC converters usually deal with relatively high power,it is important that the soft-switching function does not significantly increase the switch voltage/current stresses and converter control complexity.For most PFC applications, soft transition techniques are more efficient than other soft-switching techniques.There are two basic approaches to controlling power in a power-conditioning system.Thefirst approach is the single-stage conversion,which integrates input current control,load voltage regulation,and,possibly,input/output isolation into one power stage.The second approach is the traditional two-stage scheme,where the input stage(i.e.,a PFC converter) controls the input currents and provides a coarsely regulated output voltage,while the load regulation is performed by second-stage power conversion.The single-stage approach eliminates the intermediate dc bus in the two-stage approach and could have a simpler power stage structure,which makes it seemingly attractive for certain applications.However,with the single-stage approach,the control complexity is increased, and all power semiconductor devices are subject to the input voltage change and disturbance and may have higher voltage and current stress than with the two-stage approach.There-fore,the single-stage approach does not necessarily achieve performance and cost advantages over the two-stage approach. This paper provides a comprehensive overview of three-phase PFC techniques,with emphasis on soft-switching as-pects.Section II covers several simple topologies with single switch or consisting of single-phase converters.Section III presents the soft-switching techniques for three-phase contin-uous conduction mode(CCM)boost rectifiers,and Section IV includes a brief description of soft-switching three-phase buck rectifiers.Section V deals with the control aspect of three-phase PFC converters.Conclusions and predictions of future development trends are presented in Section VI.II.S IMPLE T HREE-P HASE PFC C IRCUITSTo reduce the converter cost and avoid the complexity of full-bridge three-phase converters,several simple topologies have been used for the low power end of three-phase PFC applications.A.Three-Phase Rectifiers Consisting of ThreeSingle-Phase PFC ConvertersA simple way to implement a PFC converter in a three-phase application is to combine three single-phase boost rectifiers at the input side,one for each phase and each followed by a dc–dc converter.This configuration is simplified in[1]by directly coupling the outputs of the three single-phase PFC converters,as is shown in Fig.1.This simplification could result in significant cost reduction,since only one dc–dc converter is required.The outputcapacitorusually does notequal,is used to eliminate the diode reverse recovery and switch turn-on loss.The auxiliaryswitchcan also bring the switch voltage to zero and creates the zero-voltage turn-on condition.Due to the much reduced switching loss,converter efficiency can be improved with the ZVT operation.Also,certain redundancy is inherent in this arrangement,since the three phase converters can operate independently.However,there are many more power semiconductor devices in the main power path and more power loss in this configuration than in a real three-phase PFC converter,as will be discussed in the later sections.As a result, the efficiency is lower than in many other topologies.The measured efficiency on a100-kHz prototype is90%with1.7-kW output power,90-V rms input and380-V output voltages [1].Due to its relatively low efficiency and high input current distortion,this topology is not suitable for high-power high-performance applications.B.Three-Phase Single-Switch DCM RectifiersHigh power factor can be easily obtained when boost,buck-boost,flyback,Sepic,Cuk,and zeta converters are operated in discontinuous current mode(DCM)with constant duty cycles. There are several such three-phase PFC topologies developed which require only one active switch[2]–[5].The single-MAO et al.:REVIEW OF POWER-FACTOR CORRECTION CIRCUITS439Fig.1.Three-phase ZVT PFC rectifier consisting of single-phase converters.switch boost rectifier,shown in Fig.2,is the most populartopology in this category,due to its simplicity and relativelygood ually,the converter is controlled by aslow voltage loop,which keeps the duty cycle of the mainswitch practically constant over a line cycle,so each inputcurrent has an envelope proportional to its corresponding phasevoltage.The duty cycle determines the magnitude of the inputcurrents and,thus,the input power,which provides a meansto regulate the output voltage.Although the input currentpeak is proportional to the sinusoidal input voltage in eachswitching cycle,the average input current is distorted by theinductor current during the discharging stage,the duration ofwhich is determined by the difference between the output andinput voltages.To reduce the distortion,the output voltagehas to be sufficiently higher than the input voltage peak tolimit the duration of the discharging stage.Fig.2(b)showsthe dependence of input current THD on the ratio of outputvoltage to input line voltage amplitude(voltage gain440IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS,VOL.44,NO.4,AUGUST1997Fig.3.Three-phase full-bridge boost rectifier.input current now is only the inductor current in the charging stage,nearly perfect sinusoidal current can be obtained.The disadvantage of thisflyback converter is the high voltage stress of the switch and the complex clamp circuit necessary to absorb the leakage energy of theflyback transformers.M B OOST R ECTIFIERSFor high-power applications,especially when high perfor-mance is required,the CCM boost rectifier is usually used, due to its high efficiency,good current quality,and low EMI emissions.The basic topology of three-phase CCM boost rectifiers,which is identical to a voltage-source inverter,is shown in Fig.3.The converter is controlled by an output voltage loop for output regulation and inner current loops which shape the input currents according to their sinusoidal references.Due to the existence of multiloop control,excellent control characteristics can be achieved if output voltage is higher than the input line voltage amplitude.Differential mode EMI emissions,inductor current rating,and switch current rating are also kept low,due to the continuous input currents. Due to the severe diode reverse-recovery problem,the major part of the switching loss in a CCM boost converter is usually the turn-on loss.Several zero-voltage switching techniques have been proposed to reduce or eliminate the switch turn-on loss,while alleviating the turn-off loss indirectly by the use of snubber capacitors.Great simplicity can be achieved if the soft-switching mechanism is applied to the dc link instead of applying to the ac side,as in the resonant dc link(RDCL)[9], [10]and other dc-link commutated converters[11]–[15].In the actively clamped RDCL shown in Fig.4(a),the dc link always resonates at a high frequency,thus enabling bridge switches to be turned on/off with zero-voltage conditions.Although device switching losses are significantly reduced,the conduction loss in the auxiliary circuit is quite high.The switches in RDCL converters also suffer from high voltage stress(usually about 1.5times the output voltage)and high circulating energy.Discrete pulse modulation(DPM)is usually used in RDCL converters to synthesize the three-phase voltages.DPM, although complex,requires the dc-link resonating frequency to be8–10times higher than the switching frequency of a PWM converter for similar current spectral performance[34] and limits the converter performance.It is desirable to be able to keep the widely used PWM control in soft-switching converters.Several topologies in[12]–[15]incorporate soft switching in PWM converters through the use of a dc-rail switch to separate the main bridge from the dc-link voltage source and a parallel resonant branch to resonate the bridge voltage to zero when a soft-switching commutation is required. However,the active dc-rail switch has to conduct high current with a large duty cycle and also causes significant conduction loss.Fortunately,in the PFC applications where bidirectional powerflow is not required,a diode can be used as the dc-rail switch.The resulting simpler and more efficient ZVT topology is shown in Fig.4(b)[8].The dc-rail diode also alleviates the short-through problem of the bridge switches and,thus, enhances the operation reliability of the rectifier.Fig.5shows the experimental waveforms of a50-kHz10-kW prototype,in which zero dc-link voltage indicates the zero-voltage turn-on of main switches.ThereducedMAO et al.:REVIEW OF POWER-FACTOR CORRECTION CIRCUITS441(a)(b)(c)(d)Fig.4.Soft-switching topologies of three-phase boost rectifier.(a)Actively clamped RDCL converter.(b)DC-rail ZVT boost rectifier.(c)ZVT boost rectifier.(d)Improved ZVT boost rectifier.current peak are reduced significantly while all main switches are turned on with zero voltage.In rectifier mode,the main switch turn-off events are the same as in an optimum SVM,in which only the two smaller phase currents are switched in each switching cycle.A prototype converter has been built for a permanent motor drive in a flywheel energy storage system [22].The experimental efficiency in both inverter mode and rectifier mode is above 97%at 100-kHz switching frequency,500-W output power,120-V dc,and 100-V peak ac voltages.Some modifications to further reduce the auxiliary switch stresses are discussed in [23]and [24].Several three-level boost rectifiers are proposed in [20]and [21]for high-voltage applications,where the switch voltage rating is reduced to half the output voltage.The three-level topologies have lower switching losses and input current ripple than conventional two-level topologies and provide a way to use power MOSFET’s for some high-voltage and high switching frequency applications.Due to the lower power loss and voltage rating of the switches,as well as the smaller boost inductance,a three-level rectifier could offer significant performance and cost advantages over two-level rectifiers.The topology in [21]seems especially attractive,since it can be viewed as paralleled single-phase PFC converters,and the active switches are in the clamp path,instead of the main power path.Fig.6shows its ZVT version proposed in [19].IV.T HREE -P HASE B UCK R ECTIFIERSA buck rectifier has some attractive features compared to a boost rectifier,such as inherent short-circuit protection,easy inrush current control,and low output voltage.In addition,its input currents can be controlled in open loop,and much wider voltage loop bandwidth can be achieved.A buck rectifier with a freewheeling diode is shown in Fig.7(a).Generally,(a)(b)Fig.5.Experimental waveforms of three-phase ZVT boost rectifier.(a)Input currents (time scale 5ms/div,vertical scale 20A/div).(b)Resonant waveforms (time scale 0.5 s =div):a buck rectifier has higher conduction loss than its boost counterpart,because more semiconductor devices are in series,and the input currents are discontinuous.However,a buck rectifier usually has lower switching loss,especially at low line conditions,where the boost rectifier’s switching loss (and also conduction loss)reaches its maximum.The worst case power loss of a three-phase buck rectifier is not necessarily higher than that of a three-phase boost rectifier.At present,three-phase buck rectifiers are not used as widely as three-phase boost rectifiers,probably because a single-phase buck442IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS,VOL.44,NO.4,AUGUST1997Fig.6.Three-phase three-level ZVT boost rectifier.(a)Nonisolated three-phase buck rectifier.(b)Isolated single-stage ZVS buckrectifier.(a)(b)Fig.7.Three-phase buck rectifiers.rectifier is not a viable technique and three-phase current-source inverters,which use the same topology as the buck rectifiers without the freewheeling diode,are not popular,except in very high-power SCR applications.However,it is possible that three-phase buck rectifiers could achieve certain performance/cost advantages over boost rectifiers for some applications,especially if the performance of bidirec-tional voltage devices [e.g.,symmetrical insulated-gate bipolar transistors (IGBT’s)]can be significantly improved with the development of power semiconductor techniques in the future.Some soft-switching topologies of nonisolated buck rectifiers are studied in [28].Single-stage power conversion with buck topology can be achieved by replacing the dc-link inductor with a transformer,as reported in [25].To reset the transformer,the dc-link voltage has to be bidirectional,and each bridge arm has to be a four-quadrant switch,which can be implemented as two back-to-back switch/diode pairs.The soft-switching version of an isolated buck rectifier [26],[27],shown in Fig.7(b),achieves zero-voltage turn-on for all switches,without any additional components,by using the same technology as in ZVS phase-shifted full-bridge dc–dc converters.The converter efficiency and cost is about the same as in a two-stage approach utilizing a CCM boost rectifier and a dc–dc converter.Fig.8shows the experimental transformer primary voltage and current waveforms of a 91-kHz prototype.The positive and negative pulses from the same phases are grouped together,and a positive pulse and a negative pulse are always used alternately,as clearly indicated by Fig.8,so that the transformer utilization is maximized.The continuous primaryMAO et al.:REVIEW OF POWER-FACTOR CORRECTION CIRCUITS443Fig.8.Primary voltage and current of ZVS buck rectifier.current is a characteristic of ZVS bridge circuits,similar to that in dc–dc converters.The measured converter efficiency is 92.2%with2-kW output power,208-V input rms,and50-V output voltages.V.C ONTROL AND S YSTEM I SSUESA.Control DesignControl of power converters usually can be divided into three functions:modulation,current control,and regulation of an output variable(the output voltage in rectifiers).In the three-phase inverter applications,the system dynamics is usually dominated by the slow electromechanical and/or large reactive components,so that the inverter dynamic performance is not very critical.Additionally,accurate ac current control is not very important in many inverter applications(except forfield-oriented drives).On the contrary,high-quality current control,without the use of large reactive components,is the major objective in PFC applications.With high switching frequencies,which are made possible through the use of soft-switching techniques,high performance and very wide bandwidth control can now be designed.The control design is facilitated by recent improvements in the modeling of three-phase converters[31],[40],[41],[48].All standard modulation techniques developed for inverters can be used in rectifier applications.An excellent survey of these techniques can be found in[37].Sinusoidal PWM (SPWM)is well suited for analog implementation[42],but causes higher switching losses and current distortion[8]. In boost rectifiers,SPWM can be used with third-harmonic injection to decrease the minimum output voltage by15%.The same effect is automatically achieved with space–vector mod-ulation(SVM)[37],which also significantly reduces switching loss and high-frequency current ripple.Many of the soft-switching techniques require the use of completely different modulation strategies[34]or modifications of the standard PWM schemes[8],[38],[39],due to the requirement of synchronizing switch turn-on instants in the three phases. The simplest current control for boost rectifiers is the hysteresis control,which combines the modulation and current control into a single function.It also provides the widest current-loop bandwidth of all schemes.The major problems with the hysteresis control are its load dependence of the switching frequency and the interference among phases,re-sulting in irregular converter operation and uneven current waveforms.These problems can be remedied by controlling two line-to-line currents(differences between the phase cur-rents)[43],[44].Average current control is widely used in three-phase recti-fiers.Because there are only two independent current variables in a three-phase rectifier,only two input currents need to be controlled.The modulation scheme is often adjusted,such that the switches in the phase carrying the highest current are disabled,so the switching loss is reduced by about50%. The control can be implemented either with analog or digital hardware.In digital implementations,two current compen-sators in rotating coordinates are usually used[31].The advantage of the digital implementation is that all control variables are constant in steady state for a balanced system, and good steady-state current quality can be easily obtained. Conversely,in the analog current control,the control variables are time-varying,and the ideal control voltages may even be discontinuous at the current zero crossing.Therefore,very fast analog controllers have to be used to achieve good current control,and the current distortion is usually higher than with the digital controllers,due tofinite controller gains at line frequency[33].Similar to dc–dc converters,the output voltage loop bandwidth for boost rectifiers is severely limited by the presence of the right-half plane zero in control-to-output transfer function[31],[45].For digital implementations,the bandwidth is limited even more by the computational and sampling delays.In the buck rectifiers,due to topological restrictions,three phases cannot operate independently.This prevents the direct use of hysteresis input current controllers.Instead,SVM or modified SPWM techniques are usually used[46],[49]. Excellent input current quality can be achieved with open loop control[47].B.Filter Design and System InteractionSince a PFC converter has to meet EMI specifications, an inputfilter is usually required.Thefilter should provide enough high-frequency noise attenuation,while keeping a low input displacement angle and should be as small and as light as possible to increase power density.A way to predict the conducted EMI emission of boost rectifiers is presented in [33],which can be easily extended to buck rectifiers.The use of multistage Cauer–Chebyshevfilters is proposed,and a complete design procedure is presented in[32].A proper damping network is necessary to ensure system stability.444IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS,VOL.44,NO.4,AUGUST 1997TABLE IF EATURE C OMPARISONOFS OFT -S WITCHING T HREE -P HASE PFC CONVERTERSBecause of losses in damping resistors,nonstandard damping schemes have to be used [32].The system interaction between the converter and the input filter (including line impedance)is an important and complex issue.Since a three-phase converter is intended for high-power applications,it is characterized by low input impedance.On the other hand,the output impedance of the input filter cannot be reduced arbitrarily,since its capacitance is limited by displacement factor requirements [32].As a result,the filter output impedance and converter input impedance usually overlap over a certain frequency range,and system interaction may occur,especially when high line frequency is used.The interaction in the buck rectifier has been addressed in [47],while a general stability analysis is presented in [48].The interaction at the dc link is also a critical issue in two-stage PFC converters,since the second stage presents to the front-end rectifier a constant power (negative resistance in small signal sense),due to its tight output voltage regulation.System design should involve considerations similar to those used in distributed dc power systems [50].As a general guideline,the converter should be designed with enough input inductance and output capacitance to sufficiently increase the input impedance and lower the output impedance at higher frequencies.The control design also plays an important role in alleviating the system interaction.VI.C ONCLUSIONSThis paper has given a comprehensive review of recent developments in three-phase PFC techniques,especially soft-switching techniques.It can be expected that soft-switching converters will be an increasingly viable alternative to theconventional hard-switching power conversion in many high-performance applications,since they can alleviate or solve some problems which have plagued hard-switching convert-ers for many years.At least,soft-switching techniques can provide another dimension to optimize the PFC system.Table I summarizes the main features of several three-phase soft-switching PFC topologies.However,soft-switching techniques in high-power converters are still at the early development stage.To realize the full potential of soft switching for different applications,more evaluation and practical design work are still needed.The efficiency improvement,i.e.,the power loss reduction,of soft-switching converters is an important advantage and has been demonstrated in many previous papers.However,the soft-switching operation also creates favorable switching trajectories for power switches,thus improving the reliability,voltage-current stress,and EMI emissions of the power converter.These factors could have a significant impact on the performance,cost,and design practice of power conversion equipment and need to be assessed in more detail in the future.A.Future DevelopmentIt can be expected that the use of three-phase PFC circuits will grow substantially in the future.The growth will be most prominent in applications such as telecommunications,autonomous ac power systems (e.g.,aircraft and ships),and other applications where performance and/or power density are critical.In the consumer and industrial markets,the growth will be mainly conditioned by new power-quality regulations,due to the significant add-on cost of active PFC when com-pared to diode rectification and bulky passive filter.For low-MAO et al.:REVIEW OF POWER-FACTOR CORRECTION CIRCUITS445power applications,the simple three-phase PFC circuits may provide a cost-effective solution with satisfactory performance. At the high-power end,the tradeoff between passive harmonic filtering and the active PFC with mandatory high-frequency EMIfiltering tends to be in favor of the active circuits in the future,also.Most of the three-phase inverter topologies and control technologies can be easily adapted for PFC applications. For example,regenerative,current-regulated voltage-source inverters for motor drives can be directly used as boost rectifiers with minimum modifications.However,the issues of high-frequency operation,input current quality,EMIfiltering, high efficiency,and power density remain the driving force. 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基于SVPWM的三电平拓扑仿真与实验杨智，赵正明，胡璇罗浩电机传动系，国电南京自动化有限公司，南京210003，中国电气工程与应用电子技术，清华大学，北京100084，中国摘要：三电平逆变器已成为电力电子领域的研究热点。

在对三电平拓扑结构进行研究的基础上，给出了逆变器各节点的运行参数和波形，为设计可靠的系统和选择合适的半导体器件提供了参考。

一个三电平逆变器控制系统模型的提出和模拟在PSIM（PowerSIM），以及仿真的相关波形和数据详细。

同时给出了基于该设计的实际实验的运行参数和波形。

通过比较，证明了该控制系统的有效性。

还介绍了常用的半导体选择方法。

一、引言可靠性与价格成为电力电子的重要研究对象[ 1 ]。

然而，拓扑结构、控制方法、半导体选择、分布参数、工作条件等多方面因素影响着实际情况。

因此，一个成功的产品的设计应密切相关的分析，设计，仿真，实验的系统许多论文给出了SVPWM仿真，但不给出主电路的波形。

本文将讨论的三电平逆变器的拓扑结构，并提供模拟的配置（基于PSIM）。

在系统中选择主要的电气节点显示的电流和电压波形。

同时，一个三级调速55kW变频系统实验平台，是考虑到现实。

在实验中，主要的电气节点的真实波形的测量仪器，并将实验结果与仿真结果进行比较，以验证模型的正确性和合理性。

同时，对三电平逆变器的运行过程、主电路的特性、不同电节点之间的关系进行了分析。

为半导体器件的选择、工作站的分析、系统的设计和实验提供了参考。

二、控制算法模型众所周知，如果电流和电压波形能在电机间隙中形成圆旋转磁场，那么逆变器就具有良好的性能。

交-直-交变频器的输出脉冲电压的半导体。

如果脉冲电压可以使旋转磁场，电机将顺利运行。

因此，SVPWM算法就应该如此工作。

控制模型与PSIM的算法基于SVPWM算法。

图1中，每个参数都可以在仿真中进行调整。

图（1）控制算法模型三、主电路模型主电路模型是典型的三电平逆变器拓扑结构，如图2所示。

合肥工业大学硕士学位论文三电平SVPWM算法研究及仿真姓名：李启明申请学位级别：硕士专业：电力电子与电力传动指导教师：苏建徽20071201第１章绪论１．１三电平技术研究意义能源短缺和环境污染是人类当前面临的共同的世纪性难题。

２０世纪７０年代以来两次世界性的能源危机以及当前环境问题的严重性，引起世界各国对节能技术的广泛关注。

我国能源生产和消费已列世界前茅，但仍远远满足不了工业生产和人民生活发展的需要。

由于缺电，正常的生产秩序被打乱，造成巨大的经济损失；在能源十分紧张的情况下，浪费现象仍十分严重。

例如，在工业用电中，高压大功率电机拖动的风机、水泵占很大比例，这些设备每天都在消耗大量的电能。

如果采用高压大容量变频调速装置拖动交流电机，对降低单产能耗具有重大意义。

在轧钢、造纸、水泥、煤炭、铁路及船舶等工业和生活领域中也广泛使用大中容量高性能交流电机调速系统。

此时，交流调速系统的应用可改善工艺条件，实现整个系统的性能最佳，并大大提高生产效率和产品质量。

另外，解决环境污染的重要途径是发展高速公共交通工具（如电力机车、城市地铁和轻轨），其核心也是大容量交流电机调速技术。

然而，随着交流调速及电力电子装置等非线性设备在工业、交通及家电中的大量应用，电网中的无功和谐波污染日益严重。

电力系统中的无功和谐波降低了电能的生产、传输和利用的效率，同时降低了电器设备运行的可靠性，严重时损坏设备、危及电网的安全。

以柔性交流输电系统（ＦＡＣＴＳ）技术为代表的大功率电力电子技术，在电力系统中的应用可大幅度改善电力系统可控性及可靠性，提高输电线路的传输能力及系统的安全稳定性。

在柔性交流输电系统中，采用高压大容量电力电子装置构成的无功补偿和电力有源滤波器无疑是一个发展趋势。

从２０世纪９０年代以来，以高压ＩＧＢＴ、ＩＧＣＴ为代表的性能优异的复合器件的发展引人注目，并在此基础上产生了很多新型的高压大容量变换拓扑结构，成为国内外学者和工业界研究的重要课题，使得传统上在大功率应用领域中占主导地位的ＳＣＲ、ＧＴＯ及其变换器结构受到强有力的挑战。

三电平空间电压矢量的PSIM仿真三电平空间电压矢量仿真一. 三电平的主电路结构本方针三电平逆变电路的主回路采用二极管钳位型拓扑结构，如图1所示图1 三电平逆变器主电路二. 三电平的仿真计算2.1 三电平逆变器SVPWM的α-β计算方法三电平逆变器与两电平SVPWM逆变器在SVPWM调制原理上是一致的，但由于三电平逆变器需要控制的矢量比两电平的多，算法也复杂。

三电平逆变器的SVPWM算法，主要包括参考矢量所在的扇区号的判断，开关矢量作用时间计算，及所选矢量作用顺序的确定。

三电平逆变器共有27个基本矢量可供选择，整个空间电压矢量图划分为6个大扇区36个小三角形区域(见图2)。

图2 图2 三电平逆变器SVPWM算法区域划分本文采用α-β极坐标计算法，整个算法的基本思想是:1，确定用来合成参考电压矢量的三个系统内部电压矢量;2，参考矢量所在扇区及区域的判断;3，各个矢量作用时间的计算;4，确定实际的开关矢量及其作用顺序。

(1) 参考电压矢量所在的大扇区的判断结合图3.，由正六边形空间矢量图可以看出:其中，由上式可以转化为则Vr处于第?扇区;同理，如果则Vr处于第?扇区;同理，如果则Vr处于第?扇区;同理，如果则Vr处于第?扇区;同理，如果则Vr处于第?扇区;同理，如果则Vr处于第?扇区;对以上条件作进一步分析，上述判断方法可进一步简化。

Vr所在扇区由三式与0的关系决定，由此，可以定义变量定义三个变量A，B，C，若Vrl>0，则A=1，否则A=0;若Vr2>0，则B=1，否则B=0;若Vr3>0，则C=1，否则C=0。

组合共有8种，但A、B、C不会同时为1或同时为0，所以实际的组合是6种，令N=A+2B+4C，A、B、C的组合取不同的值对应着不同的扇区，并且是一一对应的。

N与扇区数sector的对应关系如表1。

(2) 参考电压矢量所在小三角形区域的判断每一个扇区又可以分为六个小区域。

以第I扇区为例，如图4所示。

（2014届）本科毕业设计（论文）资料2014届本科毕业设计（论文）资料第一部分毕业论文（2014届）本科毕业设计（论文）2014年5月摘要此篇论文在参考了大量资料后对空间矢量脉宽调制技术进行了有理论有仿真的论述，充分发掘了此技术在现实生活中的重要性，是我们实现对永磁同步电机控制优化的重要辅助。

本文先从理论上对空间矢量脉宽调制技术进行了充分的说明然后对理论通过MATLAB/SIMULINK进行了仿真，在之后的波形图中我们可以看见空间脉宽矢量调节技术对于圆形磁场的建立，对于电机的控制都起到了良好的效果。

而永磁同步电机有者占用空间小，适用领域广等优点，桎梏其发展的永磁体材料稀少也由钕铁硼永磁材料的出现而得到化解。

我国有着丰厚的稀土资源对于永磁同步电机的发展有着得天独厚的优势，所以我们应该对永磁同步电机的控制也要有相应的技术基础，毕竟无法控制的电机就是一块金属罢了。

通过MATLAB/SIMULINK的仿真我们也可以以简单的方式获得一些不简单的控制结果，看到空间脉宽矢量调节技术是一种非常好的控制永磁同步电机的的方法。

关键词：永磁同步电机控制，空间脉宽矢量控制，MATLAB/SIMULINK仿真ABSTRACTThis paper in reference to a large amount of information on the space vector pulse width modulation technology were described with theoretical simulation, Fully explore the importance of this technology in the real life, Is our important auxiliary optimized control of permanent magnet synchronous motor, This article first from the theory of space vector pulse width modulation technology make a statement ,Then the theory of simulation by MATLAB/SIMULINK ,We can see in the waveform figure after space pulse width for the establishment of the circular magnetic field vector control technology, For the control of the motor has played a good effect,The permanent magnet synchronous motor has a small footprint, wide field of application, etc, Constraints of the development of permanent magnet material scarce also be resolved by the emergence of ndfeb permanent magnet materials , Our country has rich rare earth resource for the development of permanent magnet synchronous motor has a unique advantage, so we should control of permanent magnet synchronous motor also should have corresponding technical foundation, unable to control the motor, after all, is a piece of metal. Through MATLAB/SIMULINK simulation we can also get some in a simple way is not a simple control as a result, see space pulse width vector control technology is a very good control of permanent magnet synchronous motor.Keywords: Permanent magnet synchronous motor control, space vector control pulse width, MATLAB/SIMULINK目录摘要 (I)ABSTRACT (II)第1章绪论 (1)1.1永磁同步电机简介 (1)1.2永磁同步电机分类 (1)1.3永磁同步电机的控制方式简介 (2)1.4永磁同步电机的发展前景 (2)1.5 主要内容 (3)第2章空间脉宽矢量调节技术SVPWM (4)2.1空间脉宽矢量调节技术SVPWM的发展简况 (4)2.2 空间脉宽矢量调节技术SVPWM介绍 (4)2.3 空间矢量脉宽调制SVPWM法则推导过程 (7)2.3.1 空间矢量脉宽调制7段式 (8)2.3.2 空间矢量脉宽调制5段式 (8)2.4 合成矢量U ref所处扇区N的判断 (8)2.5 本章小结 (10)第3章 MATLAB/simulink简介 (11)3.1 MATLAB简介 (11)3.2 Simulink简介 (12)3.3 本章小结 (13)第4章三电平SVPWM的研究及其在PMSM的应用 (14)4.1永磁同步电机矢量控制的模型 (14)4.2 建模及仿真 (14)4.3仿真结果及分析 (18)结论 (20)参考文献 (22)致谢................................................................................................................ 错误!未定义书签。

基于SVPWM三相并网逆变器仿真报告目录1. SVPWM逆变器简介 (1)2. SVPWM逆变器基本原理 (2)2.1. SVPWM调制技术原理 (2)2.2. SVPWM算法实现 (5)3. SVPWM逆变器开环模型 (9)3.1. SVPWM逆变器开环模型建立 (9)3.2. SVPWM逆变器开环模型仿真分析 (12)4. SVPWM逆变器闭环模型 (14)4.1. SVPWM逆变器闭环模型建立 (14)4.2. SVPWM逆变器闭环模型仿真分析 (15)1.SVPWM逆变器简介三电平及多电平空间矢量调制(Space Vector Pulse Width Modulation，SVPWM)法是建立在空间矢量合成概念上的PWM方法。

它以三相正弦交流参考电压用一个旋转的电压矢量来代替，通过这个矢量所在位置附近三个相邻变换器的开关状态矢量，利用伏秒平衡原理对其拟和形成PWM波形。

空间矢量调制方法在大范围调制比内有很好的性能，具有很小的输出谐波含量和较高的电压利用率。

而且这种方法对各种目标的控制相对容易实现。

SVPWM技术源于三相电机调速控制系统。

随着数字化控制手段的发展，在UPS/EPS、变频器等各类三相PWM逆变电源中得到了广泛的应用。

与其他传统PWM技术相比，SVPWM技术有着母线电压利用率高、易于数字化实现、算法灵活便于实现各种优化PWM技术等众多优点。

2. SVPWM 逆变器基本原理2.1. SVPWM 调制技术原理SVPWM 的理论基础是平均值等效原理，即在一个开关周期内通过对基本电压矢量加以组合，使其平均值与给定电压矢量相等。

在某个时刻，电压矢量旋转到某个区域中，可由组成这个区域的两个相邻的非零矢量和零矢量在时间上的不同组合来得到。

两个矢量的作用时间可以一次施加，也可以在一个采样周期内分多次施加，这样通过控制各个电压矢量的作用时间，使电压空间矢量接近按圆轨迹旋转，就可以使逆变器输出近似正弦波电压。

三电平SVPWM算法研究及仿真三电平SVPWM算法研究及仿真一、引言近年来，随着电力电子技术的不断发展，交流调速系统在工业领域得到广泛应用。

为了实现高精度的交流调速，研究人员提出了各种调制技术。

在这些技术中，多电平逆变器作为交流调速系统中最重要的部分之一，其控制算法的研究和优化具有重要意义。

三电平空间矢量调制（SVPWM）算法作为一种较为有效的调制技术，广泛应用于多电平逆变器中，本文主要围绕三电平SVPWM算法的研究及仿真展开。

二、三电平SVPWM算法原理三电平SVPWM算法是采用空间矢量图形方法决定逆变器输出电压矢量的调制技术。

它通过将逆变器的输出电压矢量离散化为六个等效矢量，进而形成一种或多种适用于逆变器的控制信号。

在三电平逆变器中，根据电网的工作状态和逆变器的负载需求，可以得到逆变器的输出电压的各个组分，进而得到逆变器的输出电压矢量。

三、基于三电平SVPWM算法的控制策略在三电平逆变器应用中，SVPWM算法可用于控制逆变器输出电压的矢量。

具体而言，SVPWM算法包含以下三个步骤：1. 根据电网的输入电压和逆变器的输出电压需要，确定合适的工作模式；2. 确定逆变器输出电压矢量；3. 根据逆变器输出电压矢量，确定合适的控制信号。

四、三电平SVPWM算法的仿真实验本文采用MATLAB/Simulink软件对三电平SVPWM算法进行仿真实验。

仿真电路包括电网、三电平逆变器和负载三个部分。

仿真实验的主要目的是验证三电平SVPWM算法在逆变器输出电压调制方面的优势。

在仿真实验中，通过改变电网的输入电压、逆变器输出电流以及负载的变化来观察三电平SVPWM算法的性能。

五、仿真结果分析仿真结果表明，三电平SVPWM算法能够有效地通过控制逆变器的输出电压矢量，实现对电机的精确控制。

在不同工作负载下，三电平SVPWM算法能够实现较低的失真度和较高的功率因数。

此外，仿真结果还显示，三电平SVPWM算法具有较高的效率和稳定性，在实际应用中具有一定的可行性。

三电平逆变器简化SVPWM 控制算法仿真研究摘要：本文在介绍二极管箝位型三电平逆变器工作原理基础上，提出了一种新颖的、易于编程实现的简化三电平SVPWM 控制算法。

同时，针对三电平拓扑结构固有的中点电位波动问题，分析中点电位波动的原因和抑制方法。

基于Matlab/Simulink 平台，仿真结果验证了该控制算法的优越性，输出电压波形接近正弦，中点电位平衡。

关键词：三电平逆变器;SVPWM;中点电位控制目前，随着高压变频调速技术的发展，多电平变换器耐压水平高、通流能力强，主要应用于矿井提升、风力发电、有源电力滤波器等高压大功率领域。

与两电平成熟的拓扑结构相比，多电平变换器拓扑结构难于统一，其中交直交电压型多电平变换器可分为中点箝位型(NPC 型)和单元串联型两大类[1]。

而二极管箝位型三电平拓扑结构，由于所需功率器件少、开关频率低、输出波形阶梯数高、du / dt 小、以及易于实现高性能控制等优势，应用最为广泛。

本文在介绍二极管箝位型三电平逆变器工作原理基础上，提出一种新颖的电压空间矢量PWM 控制算法。

该算法运用熟悉的两电平SVPWM 实现流程，易于数字化实现。

同时，针对三电平逆变器直流侧中点电位波动问题，通过改变正、负小矢量作用时间，实现直流侧中点电位平衡控制。

三电平逆变器工作原理图 1 为二极管箝位型三电平逆变器拓扑结构。

直流侧由两个滤波电容( 1 2 C、C )构成，逆变侧每相桥臂由四个功率开关器件( 1 4 ~ x x S S )、四个续流二极管以及两个箝位二极管(Dx1 ~ Dx2)构成，其中开关对x1 x3 S 、S 和x2 x4S 、S 的开关状态互补(x = a、b、c)。

三电平逆变器每相桥臂可以输出0 d d +E 、、? E 三种电压，用1、0、?1标识这三种电压输出时的开关状态。

三相桥臂经组合后，共有27 种开关状态。

传统的三电平 SVPWM 控制，往往将一个扇区划分为四个小三角形区域，进而根据参考电压矢量所在区域，计算有效矢量作用时间。

三电平SVPWM算法的仿真作者：杨辉来源：《中国科技纵横》2015年第20期【摘要】针对现在开关频率的不合理，导致能耗大的问题，从而提出了空间电压矢量调制法（SVPWM）。

它是一种建立在空间电压矢量合成概念上的脉宽调制方法。

采取这种方法的好处是电压的利用率高，易于数字化实现，输出波形质量好，接近正弦，合理安排空间矢量，可以降低开关频率，减少开关损耗。

所以，本文选用空间电压矢量调制（SVPWM）作为三电平逆变器的控制方法。

【关键词】SVPWM 电压波形损耗1 SVPWM算法的研究背景及意义三电平逆变器PWM技术主要对输出电压的控制，逆变器本身运行状态的控制，包括直流电容的电压平衡控制、输出谐波控制、所有功率开关的输出功率平衡控制、器件开关损耗控制等。

目前研究比较多的是应用比较广泛的空间电压矢量调制法（SVPWM）。

空间电压矢量调制法（SVPWM）是一种建立在空间电压矢量合成概念上的脉宽调制方法，采取这种方法，电压的利用率高，易于数字化实现，输出波形质量好，接近正弦，合理安排空间矢量，不仅可以降低开关频率，而且减少开关损耗。

所以，本文选用空间电压矢量调制（SVPWM）作为三电平逆变器的控制方法。

2 三电平基本空间矢量以交流电机为负载的三相对称系统，当在电机上加三相正弦电压时，电机气隙磁通在静止坐标平面上的运动轨迹为圆形。

设三相正弦电压瞬时值表达式为：，（2.1）则它们对应的空间电压矢量定义为：（2.2）在空间矢量平面上，三电平逆变器的同一基本矢量对应不同的开关状态，说明逆变器输出的基本矢量所对应的开关状态数目具有一定的冗余度。

按照基本矢量幅值的不同进一步分类，可以将19个基本矢量及其对应的度低组开关状态分为四类，分别称为长矢量、中矢量、短矢量和零矢量。

3 参考电压矢量合成的原则为了让三电平逆变器输出的电压矢量接近圆形，并最后得到圆形的旋转磁通，只有利用逆变器的输出电平和作用时间的有限组合，用多边形去接近圆形。