Dynamic Modeling and Controller Design for a Novel Front-End Speed Regulation (FESR) Wind Turbine

Most existing wind turbine generation systems (WTGS) are based on double-fed induction generator (DFIG) and direct-drive synchronous generator (DDSG). In this paper, we investigate the modeling and controller design of a novel front-end speed regulation (FESR) wind turbine with differential variable ratio gearbox (VRG). For this wind turbine, a surface mount permanent magnet synchronous motor (SPMSM) unit is embedded to maintain the constant (i.e., synchronous) speed of the generator shaft over wide range of wind speed, which allows the conventional synchronous generator to be used to construct a grid-friendly WTGS. Compared with DFIG and DDSG, the novel FESR does not use converters for grid-connecting but adopt SPMSM to ensure the synchronous speed. A model-independent speed control algorithm for maximum power point tracking (MPPT) is developed based on a neuro-adaptive backstepping approach. Theoretical analysis and numerical simulations show that the proposed control scheme ensures more precise motor speed tracking in the presence of parameter uncertainties and external load disturbances.