A sorted modified multi-reference PWM technique for solar PV panel companion grid-tied inverters

Pulse Width Modulation (PWM) techniques are increasingly vital in solar energy-driven grid-tied companion inverters, significantly enhancing power quality. This paper proposes the Sorted Modified Multireference Pulse Width Modulation (SMMR PWM) technique. The SMMR PWM with a Maximum PowerPoint Tracking (MPPT) control strategy is implemented in a Solar PV Panel Companion Grid-Tied Inverter (SPPCGTI) system featuring single-stage power conversion. In the SPPCGTI system, each inverter's output voltage adopts a quasi-square waveform, where the pulse width correlates with the power generated by the associated solar PV panel. By employing the SMMR PWM technique with the MPPT control strategy in the SPPCGTI system, precise MPPT for each PV panel is achieved, irrespective of uniform or non-uniform irradiation conditions. Additionally, this technique reduces Total Harmonic Distortion (THD) in the AC grid current of the solar PV panel companion inverter (SPPCI) while simultaneously enhancing MPPT efficiency, inverter efficiency [inverter efficiency is less than the Sorted-Staircase Modulation (SSCM) and more than the Sorted PWM (SoPWM)], and reducing settling time compared to the existing techniques like SSCM and SoPWM. The SPPCGTI with the integrated SMMR PWM technique, MPPT algorithm, and current controller is modeled and simulated in MATLAB/Simulink. Experimental testing affirms the outstanding performance of the proposed SMMR PWM technique.