Modeling and implementation of Conventional Power Grid-Tied Solar Photovoltaic System using Constant Current Controller

Abstract

Interconnection of dynamically variable renewable electricity sources like sun, tidal and geothermal, etc. interfacing with the conventional power grid needs awareness to make sure the electrical power system is consistent and reliable. Sun energy can be converted into electrical energy via photovoltaic cells. Running characteristics of such solar photovoltaic cells to be well known to the power system designers. This can be achieved with device modeling, simulation, and experimental studies.  This paper develops a 1kW solar photovoltaic power plant which consists of a solar photovoltaic array, DC-DC step-up converter, 3-Ф Pulse Width Modulated Voltage Source Inverter (PWM-VSI) integrated with conventional power grid using Constant Current Controller (CCC). This proposed controller uses inverse Park’s transformation, Park’s transformation and Phase Locked Loop (PLL) to track the traditional power grid frequency and phase.  The LC filter is used to remove the high-frequency harmonics from the output potential, it appears to be efficient in supplying to load with a consistent voltage without phase disturbances.  The entire mathematical version of the conventional power grid-tied solar system is designed and simulated using MATLAB Simulink. Experimentally, CCC is developed using ATmega2560 microcontroller-based control system that provides the control to tune the MPP (Maximum Power Point) from a solar photovoltaic array using modified P&O method, DC bus voltage regulation, control of 3-ϕ PWM-VSI and system synchronization is also applied. The proposed controller can be validated through simulation and experimental outcomes with improved power quality features in conventional power grid-tied PV systems.