Analytical description of multilevel carrier-based PWM of arbitrary bounded input signals

A mathematical framework for analytical description of multilevel carrier-based pulse-width modulation (PWM) is presented. The framework does not make any assumptions on the input signal and is able to model any configuration of periodic, piecewise-linear carrier signals, specified by two line-segments. By using the framework it is shown that analytical equations can be obtained for two practically relevant multilevel PWM schemes. The derived equations simplify spectral analysis, which is exemplified by numerical simulations.