Active Power Reserve Control for Grid-Forming PV Sources in Microgrids using Model-based Maximum Power Point Estimation

Power curtailment of grid-forming photovoltaic (PV) sources to provide power reserves is a promising solution to deal with significant survivability challenges in PV microgrids. A control scheme is presented that is capable of providing both maximum power point (MPP) estimation and active power reserve regulation for grid-forming PV sources. Model-based MPP estimation is proposed that avoids the need for irradiance and temperature sensors. This power reserve control algorithm can provide adjustable levels of power reserves under different operating conditions. MATLAB/Simulink-based simulations and controller hardware-in-the-loop (CHiL) emulation results demonstrate the accurate and fast response of the control scheme for grid-forming PV sources in islanded microgrids. Experimental verification of the estimation and control algorithms using an installed outdoor PV array during grid- connected operation is also included to confirm its effectiveness in real-time environments.