高压多电平逆变器控制策略研究及其建模

【作者】 许文斌；

【导师】 桂武鸣； 漆文辉；

【作者基本信息】 中南大学 ， 控制工程， 2007， 硕士

【摘要】 目前,随着电气传动技术的发展,大容量传动的高压变频调速技术在交流电机驱动领域得到了普遍的应用。多电平逆变器和传统的两电平逆变器相比较而言具有输出电平数多,输出波形更逼近于正弦波等特点,成为该领域研究的热点。本文分析了二极管箝位式多电平逆变器、电容箝位式多电平逆变器、级联式多电平逆变器的工作原理和特点;论述了三角载波层叠法、特定谐波消去法、载波移相法、多载波PWM法、基于自由度组合控制的PWM法、单元矢量移相空间矢量脉宽调制法等七种控制策略的基本控制原理;并在第三章详细研究了二极管箝位式三电平逆变器带中点电位控制的空间矢量脉宽调制算法,实现了中点电位平衡;第四章提出了一种新型的级联式多电平逆变器拓扑结构并研究了其空间矢量控制算法;同时在MATLAB/SIMULINK环境下对这两种多电平逆变器系统进行了建模仿真。仿真结果表明,这两种多电平逆变器的输出线电压、线电流比较接近正弦波,从而证明了这两种控制算法的有效性。更多还原

【Abstract】 With the development of electric-driver technology, high voltage frequency conversation timing technology of large capacity driving has been applied widely in the field alterating current motor driving. Multi-levels inverter has become a researchful hotspot in this field due to the peculiarity that it has multi output levels and its output wave is more close in upon sine wave, etc, compared with two-levels inverter.The principle and characteristc of diode-clamping multi-levels inverter, capacity-clamping multi-levels inverter, cascaded multi-levels inverter are analyzed in this dissertation. Several control-strategies of multi-levels inverter are discussed. These control-strategies are Sub-harmonics PWM, Special harmonic elimination PWM, Phase chifted carrier PWM, Multi-carrier PWM, Selected harmonic elimination, Based on Control Degrees of Freedom PWM, a Phase Shifting space vector modify. The arithmetic of Space Vector Pulse Width Modify applying in diode-clamping inverter is studied particularly in the third chapter, the controlling of midspot voltage is embedded in the arithmetic which makes the midspot voltage in blanace. A new topology structure of cascaded multi-levels inverter is given, and the arithmetic of Space Vector control is researched in detail in the fourth chapter. At the same time, the models of these two inverters system are founded and simulated in the condition of MATLAB/Simulink. According to the simulation output wave of these two inverters, the conclusion that the wave of output line-voltage and line-current are comparatively close to the sine-wave is made, which proves the effectivety of these two control arithmetics.更多还原