A Hybrid PWM Strategy for SMES Integrated Grid-Feeding Transformerless PV Inverters

This paper presents a new hybrid pulse width modulation (PWM) strategy for improving the performance of superconducting magnetic energy storage (SMES) integrated solar photovoltaic (PV) based grid-feeding transformerless H6 inverter systems. The proposed PWM strategy offers significantly lower total harmonic distortion (THD) of output voltage compared to existing unipolar PWM (UPPWM), bipolar PWM (BPPWM), and some well-established advanced PWM techniques. A new carrier and reference signals are used to develop the proposed hybrid PWM strategy, which ensures low leakage current compared to existing counterparts. The presented inverter system is simulated in MATLAB/Simulink and PLECS computer simulation environment. Apart from simulated results, some preliminary experimental test results are also shown to validate the superiority of the proposed PWM strategy.