Development of Programable Emulator for the Photovoltaic Source

Abstract

With the depletion of conventional sources of energy, solar energy has emerged as a promising alternative. This increased interest in PV systems has increased demand for appropriate equipment with which to test them with different types of PV panels for different environmental condition. The testing of the systems under real conditions is difficult owing to varying weather conditions and also these different conditions are difficult to be created in laboratories. Hence an Emulator, which behaves electrically in a similar way as that of a PV source, is the need of the hour. A photovoltaic emulator is a power supply with similar current and voltage characteristics as a PV panel. Being able to mimic the electrical behavior of the PV panels, photovoltaic (PV) emulator systems make it possible to perform different PV system tests under various operation conditions. In this thesis a DC-DC Converter based Photovoltaic emulator design is presented. The emulator employs a Buck-boost type of converter with a FPGA basedNI GPIC card as the controller. This Emulator takes solar radiation and temperature as user input and the PI Controller as well as Sliding mode control were implemented to make the working point of the emulator track the reference I-V Curve for those environmental conditions. The results obtained show a good agreement between the emulator output and the reference PV characteristics.