Title :
A new PWM method to reduce beat phenomenon in large capacity inverters with low-switching frequency
Author :
Iwaji, Yoshitaka ; Sukegawa, Takashi ; Okuyama, Toshiaki ; Ikimi, Takashi ; Shigyou, Masakane ; Tobise, Masahiro
Author_Institution :
Power & Ind. Syst. R&D Div., Hitachi Ltd., Ibaraki, Japan
Abstract :
In an asynchronous PWM method, the ratio of the carrier frequency to the fundamental frequency must be at least 15-20 in order to suppress the beat phenomenon. However, it is impossible to achieve this condition for large capacity inverters (e.g. GTO inverters), when the fundamental frequency is high. Assuming that the beat phenomenon is caused by an error generated in the PWM process, the authors introduce a compensator to reduce the error. As a result, beat phenomenon can be decreased for a low carrier frequency. Effectiveness of the proposed method is shown by experimental results
Keywords :
DC-AC power convertors; PWM invertors; bipolar transistor switches; compensation; insulated gate bipolar transistors; power bipolar transistors; power semiconductor switches; switching circuits; thyristor convertors; GTO inverters; PWM invertors; asynchronous PWM method; beat phenomenon reduction; carrier frequency; compensator; fundamental frequency; low-switching frequency; AC motors; Error correction; Frequency conversion; Pulse width modulation; Pulse width modulation inverters; Space vector pulse width modulation; Switching frequency; Switching loss; Synchronous motors; Torque;
Conference_Titel :
Industry Applications Conference, 1997. Thirty-Second IAS Annual Meeting, IAS '97., Conference Record of the 1997 IEEE
Conference_Location :
New Orleans, LA
Print_ISBN :
0-7803-4067-1
DOI :
10.1109/IAS.1997.629053
