MPPT design of centralized thermoelectric generation system using adaptive compass search under non-uniform temperature distribution condition.

• An MPPT model of centralized TEG system under NTD condition is constructed. • A novel adaptive compass search is developed for MPPT of centralized TEG system. • An adaptive sequence of exploration directions is used for searching enhancement. • The proposed method can make the centralized TEG system generate more energy. • The proposed method can reduce the power fluctuation of centralized TEG system. This paper proposes a novel adaptive compass search (ACS) for maximum power point tracking (MPPT) of centralized thermoelectric generation (TEG) system under non-uniform temperature distribution (NTD) condition. The centralized TEG system employs only one converter thus the overall costs of converter implementation and maintenance can be significantly reduced compared to that of string-type and modularized configurations. However, multiple maximum power points (MPPs) usually appear for centralized TEG system when exposed under NTD condition. In order to effectively and efficiently seek the global MPP, an adaptive sequence of exploration directions is employed to considerably enhance the global searching ability of ACS through the previous searching results, which is the main improvement against to the original compass search (CS) associated with fixed sequence. Four case studies, including start-up test, step change of temperature, random temperature variation, and sensitivity analysis, are carried out to verify the effectiveness and advantage of ACS in comparison to that of perturb and observe (P&O), particle swarm optimization (PSO), whale optimization algorithm (WOA), grey wolf optimizer (GWO), and CS, respectively. Lastly, a dSpace based hardware-in-the-loop (HIL) experiment is undertaken to validate its hardware implementation feasibility. [ABSTRACT FROM AUTHOR]