Ts fuzzy based adaptive perturb algorithm for MPPT of a grid connected single stage three phase VSC interfaced PV generating system

This paper proposes an adaptive perturb maximum power point tracking algorithm for a grid connected single-stage, three-phase PV system, supplying the local load. As the Mamdani´s implications based systems are complex and take more processing time for generation of outputs in real time, a Takagi-Sugeno based fuzzy system is proposed and is used to make the perturbation adaptive. Maximum power point tracking is achieved with interleaved inner current control loop and outer voltage control loop. To convert nonlinear models into linear models, a feedback linearization scheme has been formulated, which uses the nonlinear transformation by means of diffeomorphism mapping. Sliding mode control technique has been incorporated in the feedback linearized control to add robustness to the control algorithm. The developed control algorithm along with proposed maximum power point tracking technique is tested for the maximum power extraction for various percents of rapid changes in insolation along with the changes in insolation with different ramp rates. Finally, the proposed algorithm is compared with the perturb and observe technique for evaluating its performance efficacy.