三相四桥臂逆变电源的设计毕业设计已整理.docVIP

浦江学院 2015 届毕业设计（论文） 题 目：三相四桥臂逆变电源的设计 专 业：电气工程及其自动化 班 级：浦电气1105 姓 名：张杨 指导老师：梅磊 起讫日期：2015-01~2015-06 2015年6月  三相四桥臂逆变电源的设计 摘要 传统的三相逆变电源采用三桥臂结构，但是在不对称负载情况下，三相输出电压会产生负序分量和零序分量，这些因素会干扰系统的输出效果，造成系统三相电压输出不对称。为了抑制这种不对称的情况，本文引用了三相四桥臂拓扑结构。三相四桥臂逆变电源可以在三相负载不对称时保持三相输出电压的对称输出，且具有系统容量小成本较低的优点。 本文通过建立的数学模型，由数学模型可以得到输出电压和电感电流等各个变量之间的关系，从而实现对输出电压的控制。The Design of Three-phase Four-leg Inverter Abstract Conventional three-phase inverter adopts three-leg topology. But when the loads are unsymmetric, undesired components of negative sequence and zero sequence which come from three-phase output voltages will cause unsymmetric output in system. For the sake of suppressing the asymmetry, a three-phase four-leg inverter which is proposed in this paper can ensure the three-phase symmetrical outputs when the loads are unsymmetric, in addition it has the advantage with smaller capacity and lower cost. This paper establish four bridge three-phase inverter arm of the mathematical model, the model can get four bridge three-phase inverter arm of the output voltage and current, inductance of the relationship between the different variables, so it can realize the output voltage control.The thesis have built average models of a four-leg inverter based on the symmetrical components, and proposed a improved control strategy. Symmetrical components of three-phase voltage and current are decomposed into DC quantities which can be controlled by PI in their respective reference systems. This paper describes the detailed derivation of controller design and software implementation. Keywords: four-leg three-phase inverter，mathematical model，symmetrical components，The three-phase symmetrical voltage 目 录 摘要 I ABSTRACT ………………………………………………………………………II 第一章 绪论 1 1.1本课题研究背景以及研究意义 2 1.2本课题的研究现状 3 1.2.1 具有带不对称负载能力的三相逆