A new airfoil design method for H type vertical axis wind turbine is introduced in the present study. A novel indicator is defined to evaluate vertical axis wind turbine aerodynamic performance at variable tip speed ratios and selected as the airfoil design objective. A mathematic model describing the relationship between airfoil design variables and objective is presented for direct airfoil de...

We discuss non-ideal torque control in wind turbine systems (WTS). Most high-level controllers generate a reference torque which is then send to the underlying electrical drive system (generator+inverter) of the WTS to steer the turbine/generator to its optimal operation point (depending on the wind speed). The energy production heavily depends on the mechanical power (i.e. the product of rotat...

Wind turbines are increasingly becoming significant components of power systems. To evaluate competing wind energy conversion technologies, a real-time Wind Turbine Emulator, which emulates the dynamic torque produced by an actual turbine has been developed. This is necessary since the real world performance of a wind turbine, subjected to variable wind conditions is more difficult to evaluate ...

The design of an advanced controller for wind turbine load mitigation is presented. The controller is based on Nonlinear Dynamic Inversion control methods combined with Pseudo Control Hedging to account for the actuator limits and a two degree of freedom control system for the collective pitch control of the rotor blades. The controller uses wind speed measurement information to adjust to wind ...

Variable speed wind turbines (VSWTs) usually adopt a maximum power point tracking (MPPT) method to optimize energy capture performance. Nevertheless, obtained performance offered by different MPPT methods may be affected by the impact of wind turbine (WT)’s inertia and wind speed characteristics and it needs to be clarified. In this paper, the tip speed ratio (TSR) and optimal torque (OT) metho...

The unsteady performance of a twin-entry variable geometry turbine for an automotive turbocharger is presented. A single-entry variable geometry turbine was initially designed based on a commercial nozzle-less turbine. The variable geometry single-entry volute was later modified to twin-entry through partitioning. A comprehensive range of steady testing and evaluation was also conducted as part...

This paper proposes the design of a Proportional Integral (PI) controller using Imperialist Competitive Algorithm (ICA) to control the speed of an Induction Motor (IM) fed from wind turbine. The wind turbine plays as a prime mover to a connected DC generator. Pulse Width Modulation (PWM) is used to get three phase AC voltage from the output of DC generator. The proposed design problem of speed ...

BACKGROUND Pneumomediastinum is commonly caused by iatrogenic injury such as surgery on the cervical planes and chest or by tracheostomy. It is also well known that emphysema may occur after dental treatments using an air turbine drill, but there have been few cases of emphysema which extended to the mediastinum. CASE PRESENTATION A 16-year-old boy is presented with subcutaneous emphysema and...

This paper investigates the lifetime of high power IGBTs (insulated gate bipolar transistors) used in large wind turbine applications. Since the IGBTs are critical components in a wind turbine power converter, it is of great importance to assess their reliability in the design phase of the turbine. Minimum, maximum and average junction temperatures profiles for the grid side IGBTs are estimated...

Wind power represents one of the most promising sources of renewable energy, and improvements to wind turbine design and control can have a significant impact on energy sustainability. Although wind energy has not been a canonical research area in robotics, we argue here that many robotics techniques (physical system design, modeling and control, and policy learning techniques) can in fact have...