Nonlinear Robust Backstepping Control for Three-Phase Grid-Connected PV Systems

Abstract

This paper proposes a cascade control structure for three-phase grid-connected Photovoltaic (PV) systems. The PV system consists of a PV Generator, DC/DC converter, a DC link, a DC/AC fully controlled inverter, and the main grid. For the control process, a new control strategy using nonlinear Backstepping technique is developed. This strategy comprises three targets, namely, DC/DC converter control; tight control of the DC link voltage; and delivering the desired output power to the active grid with unity power factor (PF). Moreover, the control process relies mainly on the formulation of stability based on Lyapunov functions. Maximizing the energy reproduced from a solar power generation system is investigated as well by using the Perturb and Observe (P&O) algorithm. The Energetic Macroscopic Representation (EMR) and its reverse Maximum Control Structure (MCS) are used to provide, respectively, an instantaneous average model and a cascade control structure. The robust proposed control strategy adapts well to the cascade control technique. Simulations have been conducted using Matlab/Simulink software in order to illustrate the validity and robustness of the proposed technique under different operating conditions, namely, abrupt changing weather condition, sudden parametric variations, and voltage dips, and when facing measurement uncertainties. The problem of controlling the grid-connected PV system is addressed and dealt by using the nonlinear Backstepping control.

Metaheuristic-Based Control for Three-Phase Grid-Connected Solar Photovoltaic Systems

“…The inductor and capacitor filters store energy, they are represented by square pictograms. Both converters are modeled in average value (Boujmil, Badis, & Nejib Mansouri, 2018).…”

Cascade Control of Grid-Connected PV Systems Using TLBO-Based Fractional-Order PID

“…The used representation helps to understand the relations between all the system parameters and to design controllers for the system by characterizing the tuning chains. The MCS is generated by inversion of the EMR [29,30].…”

Non-linear control for enhanced solar power under partial shading and AC load variations

“…Rivera et al [21] proposes a three-phase single-stage grid-connected PV system with a Lyapunov-based nonlinear control strategy to achieve MPP with the INC algorithm and to control the active and reactive power of the DC/AC inverter to ensure a unity power factor (UPF) on the grid side, as well as in [22]. Meanwhile, Boujmil et al [23] proposes a two-stage grid-connected PV system that is fully controlled by the nonlinear backstepping technique in his paper. The perturb and observe (P&O) algorithm is also used to investigate the maximization of reproduced energy from a solar power generation system.…”

“…The proposed control is based on the backstepping method and an energy management algorithm. Boujmil et al [23] are focuses on a dynamic stability analysis of stand-alone hybrid DC microgrids using nonlinear countercurrent (NBC) controllers that are customized for different components of the microgrid such as a PV system, rectified diesel generator, loads, and a battery energy storage system. The countercurrent controller is designed to manage the power output of these components while reducing the incongruence between generation and consumption and maintaining a constant voltage on the DC bus, which serves as the main connection point for all microgrid components.…”