Implementation of Double Loop Controller Tuned Super Lift Luo Converter and Unipolar Inverter for Solar Fed Grid Application

Abstract

The main objective of this article gives detail about the solar power conditioning system to make the PV power generation with high power quality before it is connected to the grid. The PV side DC-DC conversion is done by Positive Output Elementary Super Lift Luo converter (POESLLC) with high voltage conversion ratio for better performance. The grid side AC conversion is done by simply double loop controller is introduced in this system to keep less variation and to maintain the grid voltage constant for line and load variations. DC power received from the solar panel is stabilized in the POESLLC converter with double loop controller which consists of PI controller on the outer loop and hysteresis current controller inner loop. Open-loop Pulse Width Modulation (PWM) based unipolar full-bridge inverter is used to maintain the grid parameters to meet the power quality issues. This system avoids the closed-loop controller for inverter and also omits the Maximum Power Point Tracking (MPPT) algorithm in DC to DC conversion. It has some advantages such as fewer components, less weight and avoids complexity in controllers which inject steady current to the utility line. The effectiveness of the converters is verified through MATLAB Simulink.