Development and Testing of a Three Phase Two Stage Grid Tied Solar Photovoltaic Inverter with EV Charging Station (Support)

Abstract

This study explains how a smart inverter system is developed and tested to connect solar photovoltaic energy with the main power grid and also support electric vehicle (EV) charging. It focuses on a 100KW three- phase solar inverter that includes smart features like a boost converter to increase the voltage from solar panels and Getting the most power from the sunlight requires use of Maximum Power Point Tracking(MPPT) .The two level inverter changes the solar DC power into AC with Pulse width Modulation(PWM) control also it can be used by the grid and the rectifier change the grid AC power into DC to charge the EV charging stations.The management system manages the electrical potential (voltage), keeps the inverter in synchronization to the grid through Phase- Locked Loop (PLL), and avoids sending unwanted reactive power, making the system clean and efficient. Tests done using MATLAB/Simulink show that the system works well even when sunlight levels change. It keeps the DC voltage stable and delivers the highest possible power.Besides helping the grid; this system can also charge electric vehicles using solar power, either directly or through the grid. This reduces the use of traditional energy sources for charging EVs. Overall, smart grid-connected inverters like this are very important for the shift to renewable energy, providing a clean, smooth, stable connection between solar power, the grid, and electric vehicles.

Introduction

The project focuses on designing and developing a smart solar inverter system that efficiently converts solar energy (DC) into usable alternating current (AC) for homes, industries, and electric vehicle (EV) charging. The system uses a two-stage, three-phase inverter setup: a boost converter to increase DC voltage from solar panels and a grid-tied inverter to convert DC to AC synchronized with the grid via Phase-Locked Loop (PLL). Maximum Power Point Tracking (MPPT) ensures optimal energy extraction by dynamically adjusting to sunlight conditions. The system includes an LCL filter to clean the AC output and supports direct EV charging from solar or grid power.

Control strategies include:

• Boost converter controlled by MPPT using a Disturb & Observe algorithm.

• PLL for phase synchronization with the grid.

• Grid current controller to maintain voltage and current quality.

A grid-to-EV charging station uses a rectifier to convert AC to DC, providing a stable 320V output for EV charging.

The system was modeled and simulated in MATLAB/Simulink, showing stable voltage output and efficient power transfer under varying solar irradiance (1000, 500, 250 W/m²). The MPPT successfully maximizes power, and the inverter delivers clean, stable power to both grid and EV charging station.

Conclusion

This project outlines the design of a solar inverter configuration with three-phase input and dual-stage processing that integrates solar energy into the power grid, including EV charging capabilities. The system comprises a boost converter that incorporates maximum power point tracking (MPPT) to capture the highest energy possible from solar panels during different weather conditions. A grid-tied the inverter transforms direct current into alternating current while guaranteeing proper regulation of the energy delivered to the grid. The control system framework for the inverter operates to keep the link voltage on the main electrical circuit at a predetermined level, maintaining synchronism utilizing a PLL to synchronize with the grid and draws current from the grid, aka operates at a unity power factor, for maximal energy exchange. Also, the system enables smart EV charging which enhances the sustainability of the solution. All in all this inverter system assists with the shift towards renew able energy sources integrated with electric grids by enabling clean dependable solar energy to be used at electric grid substations and charging stations for electric vehicles.

References

[1] Mehta, G. and Singh, S.P(2014) \'Design of single-stage three-phase grid-connected photovoltaic system with MPPT and reactive power compensation control\', Int. J. Power and Energy Conversion, Vol. 5, No. 3, pp.211-227. [2] Zhou Dejia, Zhao Zhengming, M. Eltawil and Yuan Liqiang, \"Design and control of a three-phase gridconnected photovoltaic system with developed maximum power point tracking,\" 2008 Twenty-Third Annual IEEE Applied Power Electronics Conference and Exposition, 2008, pp. 973-979. [3] Khawla, E.M.; Chariag, D.E.; Sbita, L. A Control Strategy for a Three-Phase Grid Connected PV System under Grid Faults. Electronics 2019, 8, 906. [4] F. Blaabjerg, R. Teodorescu, M. Liserre, and A. V. Timbus, \"Overview of control and grid synchronization for distributed power generation systems,\" 2006. [5] D. Beriber and A. Talha, \"MPPT techniques for PV systems,\" International Conference on Power Engineering, Energy and Electrical Drives, no.May,pp.1437-1442 2013. [6] M.Villalva, J.Gazoli, and E.Filho,\"Comprehensive Approach to Modeling and Simulation of Photovoltaic Arrays,\" IEEE Transactions on Power Electronics, vol. 24, no. 5, pp. 1198-1208, 2009. [7] D. Beriber and A. Talha, \"MPPT techniques for PV systems,\" International Conference on Power Engineering, Energy and Electrical Drives, no. May, pp. 1437-1442,2013. [8] A. Reznik, M.G.Simões, A. Al-Durra and S. M.Muyeen, \"LCL Filter Design and Performance Analysis for Grid-Interconnected Systems,\" in IEEE Transactions on Industry Applications, vol. 50, no.2,pp.1225- 1232,MarchApril. [9] Guille, C., & Gross, G. (2009)A conceptual framework for the vehicle-to-grid (V2G) implementation Energy PolicyDOI: [10.1016/j.enpol.2008.10.017]

Copyright

Copyright © 2025 Sarikonda Sandhya, Dr. P. Kowstubha. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.