Doctor of Philosophy (PhD)
Electrical and Computer Engineering
A nonlinear stabilizing control scheme based on Lyapunov theory is proposed for a grid- connected hybrid photovoltaic (PV)/ battery/supercapacitor (SC) system. The system dynamics is developed in the stationary reference frame, and the state-space model of the system is derived and used to formulate the Lyapunov function (LF) candidate. The global asymptotic stability of the LF-based controller is discussed in detail. The real-time implementation feasibility of the proposed control scheme is validated through hardware-in-the-loop (HIL) studies of a grid- connected hybrid system under solar energy generation and grid load variations. To address the issue of digital computational time that leads to delays in the grid-connected systems control, a novel delay-compensating stabilizing feedback is provided. The proposed control is based on delay-compensating chain predictors for bilinear systems, and it features real-time implementation feasibility and global asymptotic stability to desired reference trajectories. Real-time simulation results of a grid-connected PV/battery/SC verify the efficacy of our method in controlling its dynamics in the presence of digital implementation delays while ensuring the delivery of desired power to the grid.
Bhogaraju, Indra Narayana, "Stabilizing Control Schemes for Grid-Connected Hybrid PV-Energy Storage Systems" (2023). LSU Doctoral Dissertations. 6126.
Available for download on Thursday, April 04, 2024