M. Joe Marshell, R. Vimala, and K.R. Aravind Britto
FPGA based conducted EMI reduction using Randomized Multistage Sigma Delta Modulator with Decimation Filter for DC-DC Converter
Dynamic Systems and Applications 30 (2021) No. 10, 1585 – 1607

https://doi.org/10.46719/dsa202130.10.04

ABSTRACT.
Generally randomized pulse width modulation techniques are employed mainly in the protection of power converters from electromagnetic interference and to obtain a large width spectrum with low amplitudes by distribution of the harmonic energy. This paper presents a randomization technique by using high resolution randomized multi stage sigma-delta PWM with decimator (RMSDMD) generation module is implemented for better comparison during the test of conducted EMI noise reduction on DC to DC converter. A unique combination of randomized PWM and sigma-delta concept has been created to overcome problems associated with noise generation. This proposed (RMSDMD) PWM wave generation modules are implemented on an Alter a FPGA device using Quartus II synthesis software tool. Experimental results depict the considerable improvement in the conducted noise spectrum and the noise level was effectively reduced in the range of 9dBμV over other PWM Modulator.

Keywords: Electromagnetic interference, DC-DC Converter, Power spectral density, RPWM, Randomized Sigma–Delta modulation with decimator filter, FPGA.