the winD inDustry has experienceD a rapid expansion. As wind farms are aging, their operations and maintenance issues are gaining in significance. The wind industry has been affected by failures of wind turbine components such as main bearings, gearboxes, and generators. Replacement of failed components results in the high cost in energy production. Therefore, research in fault identification a...

This paper presents a novel type of variable speed wind turbine with a new drive train different from the variable speed wind turbine commonly used nowadays. In this concept, a synchronous generator is directly coupled with the grid, therefore, the wind turbine transient overload capability and grid voltage support capability can be significantly improved. An electromagnetic coupling speed regu...

There is a market for small, efficient and costeffective wind generators for mini-grid and remote power systems. Direct-drive permanent magnet generators have become very attractive for this application. This paper describes the improvements achieved in an outer-rotor direct-drive permanent magnet generator by using finite element analysis and optimisation techniques. The starting torque of the...

We investigate the strong stabilization of a wind turbine tower model in the plane of the turbine blades, which comprises a nonuniform SCOLE system and a two-mass drive-train model (with gearbox). The control input is the torque created by the electrical generator. Using a strong stabilization theorem for a class of impedance passive linear systems with bounded control and observation operators...

A new maximum power extraction (MPE) controller for variable speed permanent magnet synchronous generator (PMSG) wind energy conversion systems (WECS) is proposed. The proposed controller generates optimum speed reference signal for the speed control loop of the vector controlled machine side converter control system without requiring the knowledge of wind speed using only active power and air ...

The objective of this paper is to identify suitable generator concepts for direct-drive wind turbines by reviewing directdrive and geared generator systems. Usually, in literature, comparison of different generator systems is discussed with the criteria based on the energy yield, cost, and weight. Because direct-drive permanent-magnet machines are more superior in terms of the energy yield, rel...

We investigate the suppression of the vibrations of a wind turbine tower using colocated feedback to achieve strong stability. We decompose the system into one model describing the vibrations in the plane of the turbine axis and another model in the plane of the turbine blades. In the plane of the turbine axis, we obtain a non-uniform Spacecraft Control Laboratory Experiment (SCOLE) model with ...

The main objective of this paper is to design a dynamic reference trajectory based on hysteresis to avoid saturation in controlled wind turbines. Basically, the torque controller and pitch controller set-points are hysteretically manipulated to avoid saturation and drive the system with smooth dynamic changes. Simulation results obtained from a 5MW wind turbine benchmark model show that our pro...

This paper presents an analysis by which the dynamic performances of a permanent magnet synchronous motor (PMSM) motor is controlled through a hysteresis current loop and an outer speed loop with different controllers. The dynamics of the wind turbine pumping drive system with (PI) and a fuzzy sliding mode (FSM) speed controllers are presented. In order to optimize the overall system efficiency...