CHAKIRI, Siham (LabSIPE at National School of Applied Sciences, University Choua), abouelmahjoub, younes (University of Chouaib Doukkali - El Jadida), MCHAOUAR, YOUSSEF (ESE Lab, ENSEM of Casablanca, Hassan II University of Casablanca), Abouobaida, Hassan (LabSIPE at National School of Applied Sciences, Chouaib Doukkali), Giri, Fouad (University of Caen Normandie), KHENTAOUI, OUSSAMA (National School of Applied Sciences, University Chouaib Doukkali)

Sensorless Integral Backstepping Control of a Single-Stage Photovoltaic System Connected to the Single-Phase Grid Using a Multi-Level NPC Inverter with an LCL Filter

Scheduled for presentation during the Regular Session "Active power filters control" (ThuS1T1), Thursday, July 11, 2024, 09:20−09:40, Salle des conférences

12th IFAC Symposium on Control of Power & Energy Systems, July 10-12, 2024, Rabat, Morocco

This information is tentative and subject to change. Compiled on January 2, 2025

Abstract

In this paper, the control problem of a single-phase, grid-tied photovoltaic (PV) system consisting of a three-level neutral point clamped (3L-NPC) inverter and an LCL filter is considered. The proposed controller aims at achieving threefold control objectives: (i) guaranteeing the PF correction (PFC) objective by enforcing the current of the grid to track a sinusoidal reference signal in phase with the grid voltage; (ii) controlling the DC bus capacitor voltages to follow a reference value provided by the maximum power point tracking (MPPT) algorithm to achieve the maximum available PV power; (iii) ensuring a balanced power exchange through the regulation of the two input capacitor voltages to the same values. To achieve these aims, a multi-loop nonlinear controller is synthesized, including three control loops, specifically the inner PFC requirement loop designed through the integral backstepping approach, the outer voltage control loop formulated using a filtered proportional integral (PI) regulator, and the power balance loop built up using a PI regulator. The control problem under consideration entails several difficulties as the existence of numerous state variables that are inaccessible to measurements. This challenge is addressed by adding a high-gain observer to estimate the current of the solar panels. The performance of the proposed controller against climate changes is demonstrated via numerical simulations using the MATLAB/Simulink platform.