Continuous Fault Ride-Through Control of Wind Turbine Using Energy Storage Based DVR

Continuous fault ride-through (CFRT) of wind turbines (WTs) requires WTs to go through continuously from a low voltage stage to a high voltage stage which has a different voltage dynamic process compared with single fault ride-through. And CFRT has a long fault duration. One of the solutions to alleviate the mentioned problems is a dynamic voltage restorer (DVR). However, the expensive cost and large storage requirement of the energy storage system (ESS) in dc link hamper the practical implementation of DVRs. To avoid this drawback, this paper presents a novel control consisting of adaptive mode switching and adaptive coordinated control. The adaptive mode switching control combines advantages of two basic DVR compensation solutions to decrease the DVR injected voltage amplitude and compensates for the phase jump. For CFRT, an adaptive coordination coefficient is introduced to distribute the unbalanced energy between ESS and WT rotor inertia. Furthermore, to validate the operation of the proposed control, simulations and HIL results are provided.