PROJECT TITLE :

A dc-Side Sensorless Cascaded H-BridgeMultilevel Converter Based PhotovoltaicSystem - 2016

ABSTRACT:

In this paper, a cascaded H-Bridge (CHB)-multilevel converter (MC)-based photovoltaic (PV) system with no voltage or current sensors at the dc-side is proposed. Eliminating the dc-side sensors simplifies the hardware, leading to lower cost and higher reliability of the PV system. A completely unique theme estimating the capacitors' voltages from the ac output voltage of the inverter is developed. The scheme allows replacing all dc-facet voltage sensors by a single-voltage sensor at the ac-side of the converter. Furthermore, the dc current sensors, conventionally required for the utmost power point tracking (MPPT), are also eliminated. Instead, the outputs from the capacitors' voltage control systems are utilised for the MPPT. The effectiveness of the proposed dc-facet sensorless system is experimentally demonstrated on a two-kW single-section seven-level CHB converter-based PV system.