Design and development of Reduced Switch Five Level Inverter for interfacing renewable energy sources and EV charger

This paper presents a novel topology of Reduced Switch Five Level Inverter (RSFLI) for the integration of photovoltaic based renewable energy source and Electric Vehicle (EV) charger. The new RSFLI has simple structure with low cost due to reduced switch count and it also meets the requirement of high power, medium voltage in power plants and industries. The system design integrates grid, nonlinear load, compensator, solar panel and EV charger. The proposed system is modeled in MATLAB/SIMULINK and a Third Order Sinusoidal Integrator control algorithm is used for the control of RSFLI. The RSFLI has two separate DC links. The suggested control technique regulates both DC link voltages of the RSFLI to almost equal values. The RSFLI is utilized as a compensator and coupled to a single phase power distribution system. The complete closed loop system is designed to charge as well as discharge the EV battery to support grid. A laboratory prototype hardware has been developed for the purpose of experimental validation. The proposed system is analyzed under various dynamic conditions and the results are validated using the hardware prototype. The proposed inverter configuration is further compared with conventional inverter, cascaded H-bridge 5 level inverter on several parameters. The RSFLI along with bidirectional DC–DC converter smoothly performs G2V and V2G modes of operation. The control algorithm is tested for different dynamics such as reduction in load, change in PV output and EV. Extensive hardware study has been done to test the effectiveness of proposed system and the results are found to be satisfactory.