基于PWM低开关频率选择性谐波控制方程组的实时算法  

The Algorithm of Real-time Solution of Selective Harmonic Controlling Equations for PWM With Low Switching Frequency

作　　者：张慧[1] 刘开培[1] M. Braun 陈清泉[1] 

机构地区：[1]武汉大学电气工程学院,湖北省武汉市430072 [2]Karlsruhe大学

出　　处：《中国电机工程学报》2006年第22期80-84,共5页Proceedings of the CSEE

摘　　要：针对大功率逆变器的应用介绍了一种基于不对称开关角的优化脉冲宽度调制方法。给出了该方法通过离线计算方式求解开关角的部分计算结果。在此结果的基础上利用基于均匀网路多维插值算法求取迭代初值,并通过采用有效的迭代算法和建立合理的计算规则,实现了该方法对特定谐波的幅度和相角的控制,完成了开环控制(feedforwardcontrol)状态下优化开关角的实时算法研究。采用DSPTMS320C40计算自由度为6的开关角的1次实时迭代时间大约为200μs,文中对计算开关角数字化时间量化误差的敏感性进行了分析。试验表明在1ms内能够计算出半波周期波形内6个自由度的开关角,实现了开关角的实时求取。A new optimal pulse width modulation（PWM） technique with unsymmetrical switching angles was introduced for high power applications. The exact switching angles, calculated off-line by the optimal PWM technique, were shown Then the effective initial values of the real-time solution process were obtained by interpolation based on uniform grid of off-line switching angles. The effective iterative process and algorithm of real-time solution of the optimal PWM equations were developed. Therefore a specific harmonic can be controlled by its amplitude and phase angle. A new real-time implementation scheme has been carded out in a state of feedforward control based on the solution of nonlinear harmonic equation system using a digital signal process DSPTMS320C40. The calculation time was measured for 6 independent switching angles within about 200μs for an iteration process. And the calculation of switching angles with six degrees of freedom has been performed within lms for each half fundamental period waveform. Finally the digital discrete time error sensitivity of the switching angles for harmonic output was discussed.

关 键 词：优化脉冲波形 脉冲宽度调制 实时算法 数字信号处理器 

分 类 号：TM464[电气工程—电器]