Développement, étude et mise en œuvre du contrôle hiérarchique intelligent pour un microréseau hybride dédié aux stations de télécommunication isolées

Abstract

Due to the geography of Canada, many Telecommunication Base Stations (SBT) cannot be connected to the main electrical grid and therefore must generate their own electricity using Diesel Generators (GD) in autonomous isolated microgrids. However, diesel is a source of greenhouse gas emissions (GHG) and its price is constantly fluctuating. Additionally, logistical constraints related to fuel storage and supply add complexity and increase operating costs, which affect services offered by SBT such as internet or cellular network access. The noise generated by GD can sometimes disturb wildlife as well. In spite of this, northern Canada offers some interesting opportunities in terms of solar and wind energy. The utilization of these locally available Renewable Energy Sources (RES) can reduce fuel consumption for electricity generation for the SBT. As a result, GHG emissions, operating costs, and service prices would be reduced. Microgrids are usually reinforced with energy storage systems to compensate for the stochastic nature of RES. GD should serve as backup power sources to limit investment costs and guarantee uninterrupted access to stable energy. The introduction of different energy sources in the same installation raises new challenges, particularly related to synchronization between the different system elements, protection, maximization of energy balance, power exchange, stability, and continuity of service. Advanced control algorithms are required to address these different challenges. In this context, intelligent algorithms are introduced at various hierarchical levels to ensure the proper functioning of the microgrid. A Finite Set Model Predictive Control (FS-MPC) is proposed for the primary level controllers of hierarchical control to ensure the maximization of the power extracted from the RESs, the regulation of the DC bus voltage, the control of the battery current and the voltage and frequency regulation at the local microgrid connection point (PCC). A combination of the FSMPC and the Lyapunov stability theory are also used to define the cost functions while reducing computational burden. Furthermore, a control algorithm for the secondary level of hierarchical control is developed and implemented to adjust the active and reactive power references of the inverter and manage the power exchanges within the microgrid. Real-time implementation of the BFO (Bacterial Foraging Optimization) method is used for this power management algorithm. The Modbus RTU communication protocol (Remote Terminal Unit) is implemented to allow information to be exchanged between the different levels of the hierarchical control. Through MATLAB/Simulink and laboratory tests, the proposed hybrid microgrid architecture and hierarchical control system are validated under various operating conditions.

Date	17 Sept 2023
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Ambrish Chandra (Supervisor) & Miloud Rezkallah (Co-supervisor)