Harmonic Analysis of Random Zerovector Distribution Space Vector Pulsewidth Modulation

Abstract:

The sources of the flux error were analyzed,and the theoretic flux error region was proposed in the motor control based on the space vector pulsewidth modulation.The harmonic distortion factor formula was deduced through the ripple current on the microscopic level (switching period) and macroscopic level (fundamental period).Finally the formula was analyzed,and some essential characteristics of the random zerovector distribution pulsewidth modulation (RZDPWM) were revealed.The simulation results verify the theoretic analyses.The results show that the performance decreases with the modulation index reaching the maximum value,the meansquare value is highly dependent on the numerical characteristic of the random variable,and the random movement of the error triangle along the flux/current circle is the key element that makes the spectrum expanded.

Key words:random zerovector distribution; random pulsewidth modulation (RPWM); harmonic wave; space vector pulsewidth modulation (SVPWM); flux error