Adaptive MPPT control applied to virtual synchronous generator to extend the inertial response of type-4 wind turbine generators

Abstract

The increasing penetration level of wind generation in power systems has resulted in the degradation of the system frequency response and stability issues, where the decrease of the system equivalent inertia is one of the main causes of these problems. In this context, this work proposes an operational and control approach to provide emulated inertial response to wind turbine generators based on fully rated converter that operate at the maximum power point. The inertial response of the wind turbine generator is extended by a control strategy that combines an adaptive MPPT control with an adaptive inertia control based on virtual synchronous generator. The proposed approach mitigates the antagonistic interaction between the traditional MPPT control and inertia control. The impact of the MPPT control and inertia control on the dynamics of the wind turbine and system frequency is comprehensively addressed. The results have shown that the proposed strategy is effective in extending the inertial response of the wind turbine generator and mitigating the amplitude of the second frequency dip and electromechanical oscillations caused by the conventional MPPT control. The adaptive inertia control also prevents the violation of the minimum speed limit of the wind turbine