Chang-Han Bae, Kyo-Beum Lee, and Kwang-Won Lee, “Sinusoidalisation of the input current in boost-type rectifier using sigma–delta modulation schemes,” IEE Proceedings – Electric Power Applications, vol. 151, no. 6, pp. 679–684, Nov. 2004. -SCI > Paper

Sigma-delta modulation (SDM) schemes are presented as a powerful approach to attain sinusoidal input current in a boost-type

rectifier (BTR). The SDM schemes generate long on-state duration of the switch at the start of each half-cycle in a BTR. They also

have harmonic-spreading effects. By virtue of these advantages, the dominant low-frequency harmonics in the input current are

effectively reduced. The difference between the sinusoidal reference and the actual input current in a BTR is estimated after voltage

zero crossings. The input current waveforms and their spectra are compared in cases of SDM and the conventional PWM. The

performances of the SDM schemes have been validated on a 1.6 kW BTR using a computer simulation package. The total harmonic

distortion in the input current confirms that the SDM schemes yield more sinusoidal input current waveform than the fixed switching

frequency PWM scheme.