Simulation of Load Behavior Based on Perturb-Observation Method in Non-Isolated Boost Converter for Maximum Power Point Tracking of Thermoelectric Generators

Abstract

The efficiency of thermoelectric generators (TEGs) is quite low. To operate the TEGs at the maximum power point (MPP), the internal resistance of the connected load and the TEG must be equal. This is not always possible. For this, converters containing the maximum power point tracking (MPPT) algorithm tracking MPP are placed between the TEG and the load. These converters cannot perform MPPT on every connected load value. The aim of this study is to investigate at which load values MPPT can be performed in non-isolated boost converters by using perturb & observation (P&O) method. For this purpose, a 50 W converter was designed with a 45.76 W TEG in MATLAB/Simulink environment. Load resistance value has been increased starting from the minimum value up to 5.84 ohm being the internal resistance value of the TEG. For this case, the amount of error in MPPT was large up to the internal resistance value of the TEG. In other words, the P&O algorithm could not perform MPPT. When the load resistance value started from 5.84 ohms and increased to larger values, MPPT could be performed by means of the non-isolated boost converter with the P&O algorithm.