A Multifunctional Solar PV-SyRG Based Hydr Generation Utility Interactive Microgrid

摘要

This work focuses on a control technique extended second-order generalized integrator with frequency locked loop (Ext-SOGI-FLL) for the synchronization of power converter-based equipment because of ease in digital execution and satisfactory performance. In the existing phase-locked loop (PLL) based control, the loop filter used cannot entirely remove harmonics. Hence, the harmonics in voltage considerably affects the frequency as well as phase extraction, both in dynamic and steady-state situation. To deal with this problem in the implemented system, the VSC (Voltage Source Converter) is gated in the grid-connected mode by Ext-SOGI-FLL control and for an islanded mode, VSC is switched to the PI (Proportional Integrator) control. The implemented control algorithm extracts the fundamental load voltage and current for assessment of phase angle and reference grid current (maintaining the required IEEE power quality standard-519). The FLL based control is also cable of estimating the exact frequency and phase magnitude, which suffer from phase offset due to frequency change. The comparative results validate that the response of Ext-SOGI-FLL in comparison to the existing control algorithm is faster at load and generation perturbations. Simulated results for single-stage solar photovoltaic (PV)-SyRG (Synchronous Reluctance Generator) for pico-hydropower generation, and BES (Battery Energy Storage) based microgrid is simulated in MATLAB/Simulink platform and it is validated it works successfully while feeding local loads uninterruptedly.