Coordinated Control Strategy for Hybrid Off-Grid System based on Variable Speed Diesel Generator

This paper presents a coordinated control strategy for a cost-effective, hybrid off-grid configuration based on a variable-speed diesel generator. The development of a coordinated control strategy is aimed at fuel efficiency and running cost reduction with AC voltage and system frequency regulation, power quality improvement, maximum power point tracking (MPPT), and battery protection. To reduce fuel consumption, the diesel engine driven variable speed doubly-fed induction generator (DFIG), is controlled using indirect stator flux-oriented technique. The dynamic model of the DC-DC boost converter is integrated with the perturbation and observation (P&O) method for obtaining smooth and efficient MPPT. A Simple PI controller is used for DC link voltage control, the power balance in the system, and the battery overcharging protection. The performance simulation is obtained using MATLAB/Simulink and validated on real-time hardware to demonstrate the effectiveness of the coordinated control under variation of loading and weather conditions.