Comprehensive review on control strategies of parallel-interfaced voltage source inverters for distributed power generation system

摘要

The distributed power generation system (DPGS) with renewable energy sources is gaining popularity over conventional sources of energy. Although the renewable sources of energy are available in abundance and are eco-friendly, yet, they have intermittent nature. As a result, renewable energy-based DPGS face difficulty in power transfer during adverse atmospheric conditions. Also, if the interfacing unit is a single inverter, its switches have to withstand a large amount of heat and handle a high value of current. Henceforth, to ensure uninterrupted supply and reduce voltage stress on switches, the power inverters need to be connected in parallel. This study presents various current and power-sharing control strategies of parallel-interfaced voltage source inverters with a common AC bus. A detailed classification and analysis of wired and wireless (droop) controllers for parallel-connected voltage source inverters have been done. Moreover, the recent trends and improvements in traditional droop controllers are presented. Finally, a comparative analysis among the various wired and wireless controllers is done, listing their advantages and limitations.