Enhancing Grid Stability with Synchronverter-Based Control for Grid-Side Converters in Wind Power Systems

Abstract

This paper proposes a new synchronverter control strategy for wind turbine grid-side converters, aimed at bolstering grid resilience by providing essential inertial frequency support without the need for additional energy storage components. The strategy harnesses the inherent energy storage capability of the DC-link capacitor to emulate the dynamic behavior of a synchronous generator, effectively contributing to grid inertia. A dual-controller architecture is implemented, consisting of a slow PI controller to maintain DC voltage stability and a fast protection mechanism to prevent overvoltage and undervoltage excursions. Critically, the control scheme facilitates controlled reductions of up to 10% in the DC-link voltage, generating a power reserve that can be strategically deployed for inertia emulation while preserving safe operating limits. The efficacy of the proposed method is validated through simulations of a representative three-turbine wind power plant, incorporating coordinated operation via virtual friction for inter-machine damping and local-global control strategies. Results showcase the superior performance of the proposed strategy compared to conventional grid-following control, emphasizing its potential to significantly improve grid stability and address the increasing challenges posed by high renewable energy penetration.