Asymmetrical PWM method for AC chopper with improved input power factor

An asymmetrical pulsewidth modulated (APWM) control technique for AC choppers, which can improve the input power factor as well as the harmonic contents, is proposed. A switching scheme for the proposed technique is suggested. Using digital simulation, several characteristics are investigated theoretically and then compared with those of the conventional PWM one. Practical experimental results have good agreement with the calculated ones, proving the feasibility of the proposed technique.<<ETX>>

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