A NEW PWM INVERTER WITH MINIMUM TOTAL HARMONIC DISTORTION

Abstract

Drives with a wide range of variablc speed using induction muwrs have various applications. By the great progress in microdcctronics today digital control of such drives became a reality. PWM inverter is one of the best techniques used in rower inveners to obtain controllable ac output. There are two main methods of PWM signal generation either conventional (analogue) or digital. Many authors obtained optimum PWiv1 signal with optimum harmomc content while other proposed PWM signal by eliminating low order harmonics. This paper introduces new PWM inverter signab based on binary programming as a good method for optimal PWM inverter. By comparing the proposed signal with other optimum signaL; presemcd by different authors vve found that the proposed one has superior feature than the others. The comparison based on computing the total harmonic distorion iT.H.D.) for most well known techniques and between the proposed one, taking into consideration the number of commutation per half cycie "N". The comparison shows that the proposed technique give minimum T.H.D.