A novel nonlinear sliding mode controller for a single stage grid-connected photovoltaic system

Area of Science:

• Electrical Engineering
• Renewable Energy Systems
• Control Theory

Background:

• Grid-connected photovoltaic (PV) systems require advanced control strategies for efficient power conversion.
• Maximizing power extraction and maintaining a unity power factor are critical for grid integration.
• Existing sliding mode controllers may face limitations in performance and robustness.

Purpose of the Study:

• To propose a novel nonlinear sliding mode controller for single-stage grid-connected PV systems.
• To design a new nonlinear sliding surface for improved controller performance.
• To enhance maximum power point tracking (MPPT) by controlling the DC-link voltage (Vdc).

Main Methods:

• Development of a novel nonlinear sliding surface for a first-order sliding mode controller.
• Implementation of the controller to track the DC-link voltage (Vdc) for maximum power extraction.
• Comparative analysis using numerical simulations and experimental results against existing controllers.

Main Results:

• The proposed controller achieves maximum power extraction and unity power factor operation.
• The novel sliding surface results in a first-order sliding mode controller.
• The controller demonstrates superior performance in power extraction compared to existing methods.
• Enhanced robustness against system uncertainties and external disturbances was observed.

Conclusions:

• The proposed nonlinear sliding mode controller offers significant advantages for grid-connected PV systems.
• The novel sliding surface design leads to improved efficiency and robustness.
• This controller represents a promising advancement for solar energy utilization.