Implementation of the single bit ΣΔ pulse width modulator for Maximum Power Point Tracking

Maximum power point tracking (MPPT) is an essential component for most PV modules where the load impedance very rarely matches that of the PV module itself. In most MPPT applications, a DC-DC converter is used to match the load impedance where the load impedance is emulated using pulse width modulation (PWM) to regulate the switch of the converter. In this paper, the single bit delta sigma (ΣΔ) combined PWM (PDM-PWM) is introduced as an alternative to the conventional counter based PWM for regulating the DC-DC converter's load impedance. Unlike many previous publications, this paper discusses the usage of ΣΔ PWM in the MPPT perspective as opposed to voltage regulation. It shall be shown through simulation that when ΣΔ PWM modulation is used in replacement of the counter based PWM, a slightly higher power is tracked and the ripples in the steady state response are reduced.