RANDOMIZED MODULATION OF POWER CONVERTERS VIA MARKOV-CHAINS

Randomized modulation of switching in power converters holds promise f or reducing filtering requirements and reducing acoustic noise in moto r drive applications, This paper is devoted to issues in analysis and synthesis of randomized modulation schemes based on finite Markov chai ns, The main advantage of this novel type of randomized modulation is the availability of an explicit control of time-domain performance, in addition to the possibility of shaping the power spectra of signals o f interest, We focus on the power spectra of the switching functions t hat govern converter operation, and on the power spectra of certain as sociated waveforms. Numerical (Monte Carlo) and experimental verificat ions for our power spectral formulas are presented, We also formulate representative narrow- and wideband synthesis problems in randomized m odulation, and solve them numerically. Our results suggest that random ized modulation is very effective in satisfying narrow-band constraint s, but has limited effectiveness in meeting wide-band signal power con straints.