Simple analytical and graphical tools for carrier based PWM methods

This paper provides analytical and graphical tools for the study, performance evaluation and design of the popular carrier based PWM methods which are widely employed in PWM VSI-fed AC motor drives. Simple techniques for generating the modulation waves of the high performance PWM methods are described. The two most important modulator characteristics, the current ripple and the switching losses, are analytically modeled. The graphical illustration of these often complex multivariable functions accelerate the learning process and help understand the microscopic (per carrier cycle) and macroscopic (per fundamental cycle) behavior of all the popular PWM methods. The analytical formulae and graphics are valuable educational tools. They also aid the design and implementation of the high performance PWM methods.