摘要:矩阵变换器是一种基于双向开关并采用脉宽调制得到期望输出电压的电力变换装置,可以产生交流或者直流电压。矩阵变换器可以任意调节其输出频率,能量可以双向流动,能够任意控制输入电流、输出电压的相位,可以可以任意调节输入功率因数,并且无需大容量储能元件。其中相间的换流问题是影响矩阵变换器实现实用化的关键原因。52691
本文研究并且设计了一种具有升压电路的三相-三相矩阵式变换器,打破了传统的矩阵式电力变换器拓扑结构,从机制上解决了传统矩阵变换器电压传输比较低的问题,完成了原理的研究以及控制单元的设计。采用坐标变换法调制策略,以确保在输入三相波形不对称的情况下,可以有更好的输出性能。
根据国内无双向开关器件的这一现状,本文采用IGBT组合成一个双向开关,对四步换流策略进行了详细的研究,解决其多个双向开关之间的频繁换流存在的问题。同时,基于PSIM软件上对三相-三相矩阵式变换器双向开关四步换流策略进行实验仿真,实现双向开关间的安全切换。
毕业论文关键词: 矩阵式变换器;坐标变换;双向开关;四步换流;PSIM
Research Research on commutation mode of matrix converter s
Abstact:Matrix converter is a new type of direct AC·-AC converter using bi-directional switch for power transmission.It has gradually attracted a lot of attention by virtue of its excellent input and output characteristics.With traditional AC-AC converter and the AC - DC - AC converter compared to that of matrix converter with output frequency arbitrary regulation, two-way flow of energy, no advantage of large capacity energy storage component, and can arbitrarily control input current and output voltage of the phase, the input power factor any can adjust many obvious advantages.One of the key technical issues that influence the practical matrix converter is the commutation problem among different phases.
In this paper, breaking with the traditional matrix converter topology, we research and design a kind of three-phase matrix converter based on a step-up circuit, aimed at solving the problem of low voltage transfer ratio of the traditional matrix converter. Adopt “Venturini” method as the modulation strategy for its better output performance under conditions of asymmetric three-phase input.
At present there is no bidirectional switching device, so we adopt IGBTs
combined into bidirectional switches, and research on the four-step commutation strategy, in order to solving the problem of commutation between multiple bidirectional switches and achieve safely switching. At the same time, the step switch four step commutation strategy for three-phase matrix power converter is simulated in PSIM, and the switch is safe.
Keywords: matrix converter;coordinates transformation;Bidirectional switch;four step commutation strategy;PSIM
目录
1. 绪论 1
1.1 AC-AC的发展概述 1
1.2 传统交流变换技术存在的问题 1
1.3 矩阵式变换器 2
1.4 矩阵式变换器存在的问题 2
1.5 本课题研究意义及研究内容 3
1.5.1 本课题的研究意义 3
1.5.2 本文研究内容与主要工作 3
2. 矩阵式变换器的调制策略 4
2.1 矩阵式变换器的结构 4
2.2 矩阵变换器基本原理