Design, analysis and implementation of electronically interfaced photovoltaic system using ARM Cortex-M4 microcontroller

Abstract

This research article presents a detailed documentation regarding test-bench development of Grid Interfaced Solar Photovoltaic (GIPV) system. The proposed GIPV system is developed using Voltage Source Converter (VSC) and DC-DC boost converter. The GIPV test-bench is developed using various auxiliary circuits including voltage/current measuring circuit, signal conditioning circuit, phase-shifting circuit, complementary pulse generation circuit, and driver circuit etc. These auxiliary circuits are designed in express printed circuit board software and fabricated in laboratory to develop a complete GIPV system test-bench. A combination of modified Synchronous Reference Frame (SRF) scheme and Proportional Resonant (PR) controller is proposed for current reference generation. Amplitude adaptivity based SRF-Phase Locked Loop (SRF-PLL) is presented to precisely detect the phase-angle of grid voltage under distorted and unbalanced conditions. The prototype is implemented using a commercially cheap ARM Cortex-M4 based STM32F407VGT6 microcontroller. This microcontroller has diversified peripherals for flexible target set-up with faster computation capability and a sophisticated user interface having TCP/IP connectivity. The control structure is developed in waijung environment for automatic code generation. The effectiveness of the proposed control algorithm is tested by numerical simulations in MATLAB/Simulink. Finally, practicality of the proposed GIPV system is experimentally demonstrated using ARM based microcontroller under various operating conditions.