消谐法SHEPWM的谐波影响数值分析  

Numerical Analysis of Harmonic Influence for Selected Harmonic Elimination PWM

作　　者：王榕生[1] 吴汉光[1] 

机构地区：[1]福州大学电气工程与自动化学院,福州350108

出　　处：《电工技术学报》2011年第9期183-189,共7页Transactions of China Electrotechnical Society

摘　　要：为了研究特定谐波消除脉宽调制技术(SHEPWM)的谐波影响,采用数值法计算了SHEPWM线电压波形特征及全电压范围的谐波分布、THD、转矩脉动。并与不对称规则采样正弦波脉宽调制(SPWM)进行了数值对比。结果表明,相同开关频率下,在M>0.54区间,SHEPWM的转矩与转速脉动优于SPWM的对应值;而在M<0.54区间,SHEPWM不具有优势。在M∈[0,1]区间,SPWM的THD优于SHEPWM。因此,不同PWM的转矩脉动比值与相应的THD比值之间不具有对应关系。所得结果为客观评估SHEPWM技术性能及其谐波影响提供了新依据。In order to study SHEPWM＇s harmonic influence,the numerical analysis is applied to calculate SHEPWM line-voltage waveform characteristics,harmonics distribution,THD,and torque pulsation over the complete fundamental voltage range.Further,numeric comparisons are performed on above-mentioned parameters but with an asymmetric regular sampled SPWM.The results show that,under the same switching frequency,SHEPWM is superior to SPWM in terms of torque and speed pulsation only if the modulation index M〉0.54;while SHEPWM has no superiority if M〈0.54.The THD of SPWM outperforms that of SHEPWM if M∈.Therefore,a correlation does not exist between the torque pulsation ratio and THD ratio for different PWM.The study results provide a new basis to fairly evaluate the SHEPWM performance and its harmonic influence.

关 键 词：SHEPWM 转矩脉动 数值计算 开关角 开关频率 

分 类 号：TM464[电气工程—电器]