Maximum power point tracking of a wind generator using a SEPIC converter with LMI control

The energy conversion technologies of small wind power systems are being currently studied and new topologies have been developed to improve the performance of converters associated with variable speed wind turbines. Most maximum power point tracking (MPPT) algorithms are based on turbine torque and velocity signal feedback as well as detailed knowledge of turbine model parameters. This paper proposes the implementation of a wind energy conversion system whose power extraction algorithm does not use mechanical sensors, wind measurement or predefined values that define the turbine operating point. The algorithm is the Perturbation and Observation (P&O) method, which is applied at a Single Ended Primary Inductance Converter. The choice of the SEPIC is justified due to input current characteristics and high-power processing capacity. The step-up / step-down topology is essential for retain the output voltage at specified values. A state-feedback closed-loop control with integral action using LMIs is implemented on the converting operation within a specified region. The simulation results show the performance of the presented technique.