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Recently, variable speed wind turbines (WTs) employing dual stator-winding induction generators (DSWIGs) have gained interest in related kinds of literature. A DSWIG has two sets of stator windings known as power-winding (PW) and control-winding (CW), where CW is connected to a pulse-width modulation converter called semiconductor excitation contro...
Citations
... Considering Figure 1, the linearized power sharing equation in the dc-link section is given by [29]: ...
This paper assesses the dynamic performance of permanent magnet synchronous generator‐based wind turbine (WT) regarding the blade in‐plane fatigue loads once the WT is controlled in power control mode. Blade in‐plane oscillations, associated with the poorly blade in‐plane modes, can be excited by turbulent winds or grid disturbances that may lead to damage of the blades and reduce the drive‐train reliability. To overcome this drawback, at first, a model with three degrees of freedom is extracted for the drive‐train system, and then, an active mitigation approach is proposed to mitigate the blade in‐plane oscillations. The proposed method can effectively suppress the blade in‐plane vibrations by adding a supplementary term into the power control loop that is proportional to the speed difference between the blade and generator. The speed difference between the blade and generator is obtained by estimation of the blade‐hub and hub‐generator shaft torsional torques. Next, the performance of the proposed active mitigation approach is examined by the modal and frequency response analyses and time‐domain simulations. Finally, it is shown that the proposed approach has superior performance over the conventional approaches based on the simplified drive‐train model and crossing the measured generator speed through a band‐pass filter.
... The reference value of the active power, P g,ref , is obtained through a predefined powerspeed curve associated with aerodynamic characteristics of the WT blades. The GSC d-axis reference current, i gd,ref , is generated by the active power controller, and also to operate the GSC in unity power factor, the GSC q-axis reference current, i gq,ref , is set to zero [30]. ...
... Multi-phase generators exhibit specific advantages when compared to three-phase synchronous or asynchronous generators as parts of renewable energy systems (for instance wind power generation units or marine/tidal power generation units) [1][2][3][4]. In particular 6-phase dual star induction generators (DSIGs) consist of dual 3-phase windings in their stator, and can achieve better power rates [5][6][7][8][9]. ...
The article aims at optimizing six-phase induction generator-based renewable energy systems (6-phase IGs or dual star induction generators) through a novel nonlinear optimal control method. Six-phase induction generators appear to be advantageous compared to three-phase synchronous or asynchronous power generators, in terms of fault tolerance and improved power generation rates. The dynamic model of the six-phase induction generator is first written in a nonlinear and multivariable state-space form. It is proven that this model is differentially flat. The 6-phase IG is approximately linearized around a temporary operating point recomputed at each sampling interval to design the optimal controller. The linearization is based on first-order Taylor series expansion and the Jacobian matrices of the state-space model of the 6-phase IG. A stabilizing optimal (H-infinity) feedback controller is designed for the linearized state-space description of the six-phase IG. The feedback gains of the controller are computed by solving an algebraic Riccati equation at each iteration of the control method. Lyapunov analysis is used to demonstrate global stability for the control loop. The H-infinity Kalman Filter is also used as a robust state estimator, which allows for implementing sensorless control for 6-phase IG-based renewable energy systems. The nonlinear optimal control method achieves fast and accurate tracking of setpoints by the state variables of the 6-phase IG, under moderate variations of the control inputs.
... In addition, the direct drive (DD) PMSG has a large volume and requires a full power converter. Besides, the dual-stator winding induction generator (DSWIG) [4,5], which has two stator windings with the same pole in the stator slot, is also applied to the wind turbine. The output power of the power winding of DSWIG is direct current, which needs to be converted into alternating current (AC). ...
... Pole pair number of power winding (PW) and control winding (CW) [6,4] Phase number of PW and CW 3 ...
Abstract Dual‐stator brushless doubly fed generator (DSBDFG) is a novel generator applied for wind power generation, and the electromechanical energy conversion between the stator and rotor is realised by the magnetic field modulation of the special rotor structure. Therefore, the rotor design is critical to improve the performance of DSBDFG. In this study, the different rotor structures are compared and analysed, and the position of the non‐magnetic ring is determined. In order to reduce the computational cost and improve the optimisation efficiency, the surrogate model coupled with the multi‐island geometric algorithm is applied for the optimisation of the magnetic barrier layer of the cage barrier rotor. In addition, in order to reduce the effect of skin effect on the copper loss of cage bars of the rotor, the different simulation models, whose cage bars have different layer number, are simulated and analysed. Finally, the simulation and experimental results verify the correctness of the theoretical analysis and the effectiveness of surrogate model used for the rotor optimisation design of DSBDFG.
