Comparison of SRFT and ISOGI-QSG Control Algorithm for Grid Integrated SPV System

This paper presents a comparative analysis between the control algorithms used for the three phase grid integrated solar PV system.The adaptive based Improved Second Order Generalized Integrator quadrature signal generator (ISOGI-QSG) control is compared with the most commonly used Synchronous Reference Frame Theory(SRFT). These control algorithms are mainly implemented to improve the power quality of the grid in terms of harmonic elimination, load balancing and power factor correction. From the performance evaluation, the ISOGI-QSG based control works satisfactorily under various dynamic conditions such as unbalanced load and distorted grid. The Incremental Conductance(INC) Maximum Power point Tracking(MPPT) technique is used to track the maximum power from the solar array. This is achieved through the effective extraction of crest power from an solar PV array and control the DC bus voltage. The performance evaluation of the both control algorithms are verified by simulation results and satisfactory results are obtained. It is observed that steady state and dynamic performance of ISOGI-QSG based control is superior than SRFT control.