PWM整流器的SVPWM统一快速算法和谐波分析法  

A Unified Fast Algorithm and Analytical Voltage Harmonic Analysis for Two-Level SPVWM Rectifier

作　　者：林蕾 莫岳平 黄畅畅 LIN Lei;MO Yueping;HUANG Changchang(College of Electrical, Energy and Power Engineering of Yangzhou University, Yangzhou Jiangsu 225127, China)

机构地区：[1]扬州大学电气与能源动力工程学院,江苏扬州225127

出　　处：《微电机》2021年第1期93-100,共8页Micromotors

摘　　要：传统两电平空间矢量脉宽调制(Space Vector Pulse Width Modulation,SVPWM)算法的流程复杂,计算量比较大。本文从三相桥臂与调制电压占空比之间的关系,分离出中间变量以及自由变量,将调制算法转换为满足约束条件的自由变量的选择,并证明了此方法与传统SVPWM算法等效。提出的算法不需坐标变换和扇区判断,算法流程简化程度高,计算量大量减少。在此基础上,推导了计算调制线电压的总谐波失真(THD)和各次谐波的解析表达式,解析表达式中谐波分量的计算仅与占空比有关,并得到了THD与SVPWM的调制方式无关,即与自由变量选择无关的结论。经过理论计算和实验比对,验证了本文所创新的两电平SVPWM简化算法与电压谐波分析法的正确性。The traditional algorithm for 2-level space vector pulse width modulation(SVPWM)is complicated with large computation.In this paper,from the relationship between modulation voltage and duty ratio of three-phase bridge arm,the intermediate variables and free variable were separated,and the modulation algorithm was transformed into the selection of free variable satisfying the constraint conditions.It was proved that the proposed algorithm was equivalent to the traditional SVPWM algorithm.The proposed algorithm does not need coordinate transformation and sector judgment,reduces a lot of computation and is much easier to implement.Based on the simplified algorithm,the analytical expression for calculating the total harmonic distortion(THD)and harmonic spectrum of the modulation line voltage were derived.The calculation of harmonic components in the analytical expression was only related to the duty cycle,and was proved that THD was independent of the modulation mode of SVPWM or independent of the selection of free variables.Through the comparison between experimental and theoretical calculation,the accuracy of the proposed two-level SVPWM unified algorithm and voltage harmonic analysis method was verified.

关 键 词：SVPWM 两电平变流器 电压谐波分析 统一快速算法 总谐波失真 

分 类 号：TM46[电气工程—电器]