Title :
Optimized drive control for inverter-fed ultrasonic motors
Author :
Maas, J. ; Schulte, T. ; Grotstollen, H.
Author_Institution :
Inst for Power Electron. & Electr. Drives, Paderborn Univ., Germany
Abstract :
An optimized control scheme for the most advanced traveling wave type ultrasonic motor powered by a resonant power converter is presented and verified by measurements on a prototype drive. Basing on an averaged drive model, which reflects the slow dynamic behavior of the drive´s ultrasonic oscillations by time varying fundamental Fourier coefficients, a cascaded two-phase vector control scheme is designed. The novel drive control divides into an inner voltage and outer bending wave control compensating couplings and suppressing the beat characteristics. Since an amplitude modulation is applied instead of frequency modulation, the well known pull out phenomenon is eliminated in general. By means of an online frequency adaptation to the stator´s resonance, the drive´s performance is optimized remarkably
Keywords :
AC motor drives; DC-AC power convertors; control system analysis; control system synthesis; invertors; machine control; machine testing; machine theory; optimal control; resonant power convertors; stators; ultrasonic motors; amplitude modulation; beat characteristics suppression; cascaded two-phase vector control scheme; frequency modulation; fundamental Fourier coefficients; inverter; optimized drive control; resonant power converter; traveling wave-type ultrasonic motor; Electric variables control; Electric variables measurement; Frequency; Machine vector control; Power system modeling; Resonance; Servomotors; Stators; Ultrasonic variables measurement; Voltage control;
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.1997.643144
