A novel time-sharing dual-mode control strategy in cascaded sinusoidal inverter

Considering the distinct characteristic-differences and uneven working conditions of solar PV cells, a new solution of cascaded PV modules with time-sharing dual-mode control strategy for PV power system is proposed for achieving high power conversion efficiency, generating high output voltages. Each cascaded module contains three solar cells in series, N strings in parallel, and a time-sharing dual-mode power unit. The modular power unit depends mainly on diminishing the electrolytic DC capacitor, reducing the influence of uneven working conditions and using a bypass diode-assisted boost chopper to increase the boosting ratio. Owing to the (2M+1) level output voltage and unique selective time-sharing dual-mode control strategy, harmonic components of the output voltage and switching losses can be diminished. The unique operating principle of this novel power conditioner and its dual-mode PWM time-sharing control strategy are evaluated and verified based on simulation results.