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In this study, a maximum power point tracking (MPPT) technique based on parabolic extrapolation has been presented for thermoelectric generator systems. Conventional MPPT methods require a closed‐loop controller and perturb and observe (P&O) method to provide fast‐tracking response. However, they produce power loss due to small oscillations in the steady state. The proposed method excludes the use of closed‐loop controller and steady‐state oscillations by directly estimating the coordinates of MPP using three random operating points on the parabolic P–I curve. To substantiate the effectiveness of the parabolic extrapolation‐based MPPT algorithm, different conditions of temperature gradient and load have been applied. The results demonstrate that the proposed algorithm takes <15% of the time taken by P&O method to track the MPP. [ABSTRACT FROM AUTHOR]

This article proposes a simple copper loss minimization control algorithm to minimize copper losses of a squirrel-cage induction generator based wind energy conversion system to improve efficiency at low wind speeds. The proposed scheme does not necessitate rotor position information and an encoder. The proposed algorithm is used to find the optimum slip and stator voltage such that efficiency of the squirrel-cage induction generator is increased by minimizing the copper loss. This is particularly useful in extracting the power at low speeds, where losses form a higher percentage of input power when flux is maintained at the rated value. Especially at low wind speeds, the total copper loss can be minimized by decreasing the flux. The proposed algorithm is a simple scalar control that has the potential to reduce losses, and this has been attempted considering voltage and flux saturation limits. To validate the performance of the scheme, a comparison is made with an indirect field-oriented control scheme, in which rotor flux is maintained constant. Simulations are carried out on a typical 2-MW squirrel-cage induction generator in a MATLAB/Simulink environment (The MathWorks, Natick, Massachusetts, USA). Experimentations on 2.3-kW laboratory test setup further validate the efficacy of the proposed scheme. [ABSTRACT FROM PUBLISHER]