摘要
提出了2种开环无载波的SVPWM单模式过调制策略。对它们的特点进行分析并与现有方法作比较。其中第一种方法的调制比与修改后的电压矢量幅值有精确的线性关系,可以提高基波控制精度并有效地减少DSP的内存占用和运行时间,但THD指标较差;第二种方法THD指标较好,但基波控制精度微弱降低,且较复杂。第一种方法更适合于计算资源紧张而又对基波控制精度有高要求但对谐波指标要求较低的场合;而第二种方法则更适合于谐波指标要求较高且计算资源相对富足的应用。在一片以TITMS320LF2407ADSP为控制器的二极管箝位三电平开环V/f控制原理样机上对新提出的2种过调制方法进行实验,试验结果证明所提方法是正确和可行的。
Two novel single-mode feed-forward carrier- less-based SVPWM overmodulation strategies are proposed. Their characteristics are studied and compared with that of published method. The first method is characteristic of precise linearity between modulation index and modified amplitude of reference voltage vector in overmodulation region and thus improved control precision of fundamental component of output voltage and reduction of required DSP memory and calculation time; While the second one has better THD index, but the control precise decreases little and it is more complicated. The first method is suitable for those applications that demand high control precision of fundamental component but hold little calculation resource and have no high harmonic index requirement; While the second one is for those requiring higher harmonic index and holding plentiful calculation resource. Experiment based on V/f feed-forward-controlled neutral-point-clamped three-level model inverter using one TI TMS320LF 2407A DSP had been carded out. The result of experiment confirms that the two proposed methods are correct and feasible.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2006年第20期84-90,共7页
Proceedings of the CSEE
关键词
空间电压矢量脉宽调制
过调制
三电平逆变器
space-vector pulse width modulation
overmodulation
three-level inverter
