Design of Enhanced PLL for Single-Phase Grid Connected Transformerless Inverters

Abstract

Abstract: Renewable energy sources integrated with
conventional sources fed grid to meet the ongoing electrical
energy demands. This paper presents design of Enhanced
Phase locked loop (EPLL) for single phase grid connected
transformer less inverter. The knowledge of phase angle,
frequency, voltage magnitude is under consideration to
integrate the solar PV to single-phase grid. It is required to
track exact utility voltage vector for reliable control of power
to the grid. The paper also presents Simulink modeling,
analysis of Enhanced PLL and compares its performance with
basic phase locked loop (PLL) used.
Index Terms: Enhanced phase locked loop (EPLL),
Transformerless inverter, single phase grid connected,