Grid interface of solar PV transformer-less inverters using enhanced phase locked loop

The era of Renewable Energy sources has overtaken the usage of conventional energy sources like coal, fossil fuels etc. This paper presents grid interface of single phase transformerless inverter system using enhanced phase locked loop. To connect solar PV with grid it is required to estimate phase angle, voltage amplitude and phase angle measurement of grid and the output of inverter. It is required to track exact utility voltage vector for reliable control of power to the grid. This paper compares the frequency measurement and phase angle and voltage amplitude using simple phase locked loop system along with enhanced phase locked loop so that the enhanced phase locked loop (EPLL) is proved to be giving superior performance over simple phase locked loop. The simulation of both the techniques are pursued and the results are compared.