This paper analyzes the behavior of a Permanent Magnet Synchronous Generator (PMSG) Wind turbine using the maximum power extraction (MPE) method in response to Wind speed fluctuations. The behavior of the Wind turbine in the frequency domain will be analyzed to have the Wind turbine response in the frequency domain. By combining the Wind speed frequency content and Wind turbine frequency response, the frequency content of Wind turbine output power fluctuation will be gained. A PMSG Wind turbine system is simulated with real Wind speed data in the PSIM software environment, and the results are compared with theoretical results for validation of the model.

In this study, the improvement of the turbine performance of Savonius, one of the vertical axis Wind turbines, was carried out numerically. The numerical approach used in the improvement studies was supported by experimental results and was confirmed. Within the scope of this improvement, a Wind collector was placed in the turbine front zone to decrease the negative moment on the counter-rotating blade of the Savonius turbine. To obtain the highest turbine performance, all of the changes in the design parameters of this Wind collector, such as the Wind inlet width, Wind outlet width, collector length, and collector height, were examined, and ideal design parameters of the collector were specified. The geometric parameters of the investigated Wind collector were taken depending on the circular dimension of the Savonius turbine used. Unsteady simulations for different geometric parameters using the sliding mesh approach were performed in the CFD program. According to the numerical analysis results, the power-coefficient of the conventional turbine was increased to 0.23 levels by using the Wind collector with the ideal geometric parameters. Thus, with the use of a Wind collector, the power coefficient of a conventional Savonius Wind turbine was improved by about 54%.

Like other offshore structures, floating Wind turbines are subjected to stochastic wave and Wind loads that cause a dynamic response in the structures. Wind turbines should be designed for different conditions, such as Operational and Survival conditions. In high sea states, the response can be quite different from the operational condition. The present paper deals with coupled wave and Wind induced motion in harsh conditions, up to 15 m significant wave height and 50 m/sec average Wind speed. There are several ways to deal with the dynamic response of floating Wind turbines. The Coupled Time domain dynamic response analysis for a moored spar Wind turbine subjected to wave and Wind loads is carried out using DeepC. DeepC is well known software for calculating the coupled dynamic response of moored floating structures. The aerodynamic forces on a parked Wind turbine are calculated, based on the strip theory, and imported to the DeepC through a MATLAB interface. At each time step, the relative Wind velocity, based on the response of the structure, is calculated.

In this paper, a 3.1kW DC motor is used to simulate the static and dynamic behavior of a horizontal axis Wind turbine. The effect of the difference between the Wind turbine's inertia and DC motor on the dynamic behavior of the system, torque oscillation due to the effect of the tower shadow and Wind shear, and the effect of rotary losses in the mechanical torque of the DC motor are considered. The torque of the DC motor is controlled by the closed-loop PID controller. This closed loop has two feedbacks for the speed and current of the DC motor. The turbine calculations are performed in Matlab/Simulink and the reference signal of the turbine's torque is sent to the chopper using an interface card. Two methods are proposed to estimate the acceleration of the DC motor to improve the compensation of the turbine inertia effect: the Kalman Filter, and the second-order low-pass filter. Adjustable parameters of proposed methods are optimized using the particle swarm optimization algorithm (PSO). A 2.2 kW synchronous generator is coupled with the Wind turbine emulator and feeds a constant load. To show the effectiveness of the proposed methods the results are reported. The results indicate that the Kalman filter has a better performance in the compensation of the turbine inertia effect.