FPGA-Based Statechart Controller for MPPT of a Photovoltaic System

Abstract

Conventional Maximum Power Point Tracking (MPPT) controllers in photovoltaic (PV) systems are seen to achieve tracking speeds in range of milliseconds. Power-electronic circuits in these systems many-a-time demand faster control actions in microseconds, as they operate at high frequencies, and also, a delay in control action would lead to a corresponding power-loss. Hence, an MPPT controller delivering such fast tracking speeds would improve overall system performance. In this work, an Field Programmable Gate Array (FPGA) based Statechart Controller is developed to perform MPPT control of the PV system. The developed Statechart Controller is tested using software-in-the-loop simulation(SILS) and results are presented. With inputs from a programmable logic controller emulating PV characteristic curves, the Statechart Controller is then deployed in a target FPGA. A comparison between performance with conventional MPPT controller and Statechart Controller is presented and results indicate that the latter is more effective in terms of tracking speeds, determinism, and modularity.