| Abstract |
This paper deals with a new asymmetrical pulse width modulated (APWM) technique for single and three phase AC choppers which can control input power factor as well as improves the output waveforms quality . The PWM switching patterns at the specified phase angle are obtained by a new recursive least error squares identification algorithm and implemented by a microcontroller. Theoretical comparisons are made with conventional PWM technique and the computed performances indicate the superiority of the proposed technique. Several characteristics are investigated theoretically by digital simulation and then compared with those of the conventional PWM one. Practically experimental results, obtained from a constructed and tested microcontroller - based control system, have good agreement with the calculated ones, which proves the feasibility of proposed technique. |
