Performance investigation of multifunctional grid connected PV interleaved inverter with power quality enhancement

Design and hardware prototype development of interleaved inverter in the laboratory for photovoltaic applications is discussed in this paper. Conventional voltage source inverter (VSI) is suffering with shoot-through problems which lead to electromagnetic interference (EMI), temperature rise in power electronic devices, ringing effect, etc. To eliminate these problems, interleaved inverter topology is proposed in this paper. This topology works with control technique to perform multifunctional operation in order to enhance the system efficiency. The control strategy is distributed into two parts, one is to enhance the power harvesting from PV array using maximum power point tracking (MPPT) algorithm. Second one is self-charging of DC-link voltage control loop with double band hysteresis current controller (DBHCC). The self-charging DC-link voltage control loop generates the reference current signal for mitigating current related power quality problems and DBHCC offers lower switching frequency, therefore low switching losses. A MATLAB®/Simulink software is used for implanting the proposed system. A rigorous simulation study has been carried out to verify the multi-functionality and ruggedness of the proposed system. A laboratory prototype is developed using TMS320F28027 DSP controller to validate the simulation results. The test results show that the proposed system is performing multifunctional operation by injecting active power to the grid during day time and mitigate the PQ problems during the night time effectively without shoot-through problems.