FPGA Implementation of MPPT Using Variable Step-Size P&O Algorithm for PV Applications

This paper describes FPGA implementation of a maximum power point tracking (MPPT) for photovoltaic (PV) applications. By slightly modifying the original algorithm, an improved variable step-size P&O algorithm is realized and efficiently implemented using a hardware description language (VHDL). Subsequently, the new MPPT algorithm integrated with a solar-powered battery charging system is implemented on the XC2C384 FPGA without external sensor unit requirement. Experimental results with a commercial PV array show that the proposed algorithm outperforms the conventional controller in terms of tracking speed and mitigation of fluctuation output power in steady state operation. The overall system efficiency is well above 96%