Real-time evaluation performance of solar power grid-tie inverters/ Evaluación en tiempo-real del desempeño de inversores fotovoltaicos interconectados a la red eléctrica

Recently photovoltaic (PV) applications, as a source of electrical energy, have progressively increased in terms of generation capacity and in the sense of its spread over large areas around the world. In Mexico, the Electrical Research Institute has developed a 1 kW capacity single-phase inverter. These types of power electronic devices require continuous monitoring of their performance. This work presents a control and measurement digital system to evaluate the solar power grid-tie inverter performance. A software application, based on virtual instrumentation, was developed to monitor the main input and output electrical variables of the inverter in real time. These variables are processed to obtain: DC power input, AC power output, power factor and line harmonics; as well as peak efficiency, peak power tracking voltage, total electrical energy delivered and maximum nocturnal current consumption. The main functions of the system are: electrical signals acquisition, electrical variable calculation, tendency graphical displaying and signals and variable calculations recording in files. This system is able to connect to internet using the TCP / IP protocol, which displays information into a web page. The user can have access from Smartphones and/or personal computers from anywhere in the world.