Fuzzy control method-based maximum power point tracking algorithm for thermoelectric generators

Nowadays, alternative solutions are being sought to meet the energy needs arising from the increase in the world population and to use energy efficiently. Thermoelectric generators (TEG) are part of the sustainable energy solution by converting waste heat into electrical energy. However, since their efficiency is low, both in order to operate with the best efficiency and for power regulation, the maximum power point tracking (MPPT) algorithm must be used with DC-DC converters. Since the energy produced by TEGs depends on the temperature difference due to their structure, temperature changes affect their power output. For this reason, they need DC-DC converters for power regulation. Current, voltage and power are monitored in power regulation and MPPT applications. In this study, the fuzzy logic control (FLC) method was used for the MPPT application of TEG and its performance was compared with the basic MPPT algorithm, the mix and observe (P&O) algorithm. The variable voltage output from TEG was increased by the designed synchronous DC-DC boost converter to 26.8 V, which can be used to charge the batteries. For this purpose, the design of the DC-DC boost converter was designed and analyzed in the LTspice program and the prototype was realized by making a printed circuit board (PCB) design in the KiCAD program. The simulations of the designed system were tested in the MATLAB/Simulink environment using the model of the Kyroterm TGM-199-1.4-0.8 TEG module. The synchronous DC-DC boost converter designed for the system was added to the TEG model used in the simulation and a load resistance that changes within a unit of time was added to the output of this converter. The FLC method and P&O algorithm were successfully run with the designed simulation model. In the experimental setup of the system, a synchronous FLC MPPT algorithm boost DC-DC converter was added between the TEG and the battery. The system was run using three load designs and prototypes of the DC-DC buck converters on the battery. The established synchronous DC-DC boost converter was run with both P&O and FLC MPPT algorithms. The synchronous DC-DC boost converter with FLC MPPT algorithm was operated with an efficiency of up to 95%.