Rejection of effect of non-linearities in A PV grid integrated system using VSS-SDLMS scheme

Abstract

The integration of photovoltaic system with existing utility plays a vital role to achieve the sustainable development goals set by renewable energy agencies. The grid integration takes place by following IEEE-519 standards. Number of control strategies have already been implemented to maintain the required standard. A number of issues are encountered during the process of synchronization, such as deterioration of quality of power flow due to sudden changes in loads, switching of power semiconductor devices and variation in solar insolation. To address these aforementioned issues a Variable Step Size Sign Data Least Mean Square (VSS-SDLMS) adaptive algorithm is proposed. The proposed controller makes the reference current adaptive to the adversities. In this paper the effective application of signal processing tool i.e.VSS-SDLMS for the power quality issues is well demonstrated by implementing in a three-phase single stage grid connected Photovoltaic (PV) system. The proposed scheme employs to mitigate the harmonic contents produced due to intentional and non-intentional non-linearities in the overall system to a desired level as per IEEE-519 and also it is maintaining the power factor to unity by controlling the reactive power flow. The transient performance of VSS-SDLMS is compared with the conventional LMS based algorithms. The overall system is modelled using MATLAB/SIMULINK.