INTEGRATING BATTERY ENERGY STORAGE SYSTEM TO MITIGATE THE INTERMITENCY ISSUES OF RENEWABLE ENERGY RESOUCES IN MICROGRID

Abstract

Renewable energy resources play an important role with the augmentation in demand of energy in order to fulfil the vast gap between supply power and demand power. Microgrids play a key role in utilization of renewable energy resources. Aiming at establishing a sustainable energy system, the number of stand-alone generation system of PV with battery energy storage system (PV-BESS) is considerably increased around the world. In a real grid, the implementation and analysis of PV generation system is a very challenging task. One of the major concerns about PV power is that the change of illumination intensity as well as the sudden variation of load changes makes the output characteristic of PV non-linear that may lead to oscillations in dc link voltage exceeding rated limits which in turn affecting the quality of power and stability of the grid. Obviously, battery energy storage systems (BESSs) can be an effective solution to smooth fluctuation and to improve the stability of the power grid. For refining the MG stability many control approaches have been proposed for proper sharing of load. This research work proposes Solar (PV) and Battery Energy Storage System (BESS) based DG system in addition with robust control scheme based on the (SMC) for parallel operating (VSI) during autonomous operation of microgrid and proportional integral (PI) based control technique for BESS. Under different system conditions, the efficiency of a photovoltaic (PV's) energy supply and battery energy storage network is investigated. This research explores the system's reactions to varying solar irradiation rates of the PV model caused by environmental conditions. Specific scenarios for simulation are analyzed in which the system is often checked with fixed solar radiation and changing loading conditions. The technology of (MPPT) is important due to the reliance of PV generation on environmental conditions requiring the pv generation system to provide its full capacity. This research deals with the Perturb and Observe MPPT algorithm due to its quick response and less complex control circuit. For parallel (VSI) in autonomous mode Fixed Frequency (SMVC) technique is introduced maintains the dc link voltage oscillations, active power quality and DG system voltage output despite sudden change in solar irradiation which causes the dc link voltage to fluctuate. Such controller helps in improving responses of the system which include dynamics and steady state under sudden high-power load fluctuation scenarios. Droopvii | P a g e Integrating BESS to Mitigate the Intermittency Issues of RERs in MG is studied in order to enable power-sharing among multiple generation systems. Proportional Integral Control (PI) approach is adopted for Battery Energy Storage System where the controller ensures effective tracking of dc link voltage reference value and maintaining it with in the rated limits. Finally, the conventional proportional integral (PI) controller with PI based BESS and the proposed SMVC with PI based BESS is compared. The simulation results show the effectiveness and excellent control performance of proposed control scheme in eliminating power quality issues and maintaining stable dc link voltages. The T.H.D of output voltage for purposed control scheme was observed to be less than 5%. Whereas, 14.50% for conventional control scheme measured from the FFT analysis of MATLAB Simulink. The results also validate that, in order to remove the external disturbances and to achieve response that is robust, the suggested control technique will provide an effective solution.