# Wind Turbine Technology Trends
## 3 Discussion
### Onshore Wind Turbine Development
#### 3.1.1 Wind Turbine Blades  
Advances in technology are leading to improved wind farm performance and reliability and lower component costs. To drive its technological development, the wind energy industry has adopted materials, systems, and products from other sectors, such as sensors from electrical engineering, technologies from aerospace and shipbuilding for rotor blade manufacturing, and from the mining industry for mining technology. As wind energy technology increasingly crosses the boundaries of these sectors, the development of new technologies is needed to drive wind turbine development. When it comes to rotor blade aerodynamics, numerical analysis can provide useful information. For example, [PERSON] et al. [7] used numerical analysis to determine the angle of attack, lift coefficient, and drag-to-lift ratio for the selected blade profile of the \"Espero\" wind turbine. As a result of calculations and computer simulations, the optimal values of the coefficients for blade variants with and without geometric twist were determined: flow deceleration, ideal power, edge and blade profile losses, and specific blade tip speed ratio. Applying computational fluid dynamics, [PERSON] et al. [8] tried to optimize the shape of the blade tip. The performance prediction of aerodynamic design of a blade using Deep Learning method was presented in the work of [PERSON] et al. [9]. Two parameterization methods based on geometric relations and neural network are proposed. The methods can generate smooth and complete blade profiles. Overlong blades pose a special problem. The problems of aerodynamics of such blades have been studied by [PERSON] et al. [10]. [PERSON] et al. [11] addressed the problem of surface erosion at the leading edge of the rotor blades. This can be a major problem for wind turbine reliability as it leads to reduced performance, unbalanced aerodynamic loads, increased noise emissions, and additional maintenance costs. If not corrected, it leads to deterioration of blade functionality. The twist angle distribution (TAD) along the blades determines their efficiency in terms of power generation. Since wind blades are usually used in dynamic wind environments where the wind speed varies greatly, it is important to find the optimal TAD for different wind speeds. In their work, [PERSON] et al. [12] present a learning-based method for finding the optimal TAD, which they call RL-TAD. A case study was conducted to validate the proposed method. This study indicates that the method can converge to the optimal TAD three to five times faster than the method based on a genetic algorithm. The objective of the research of [PERSON] and [PERSON] [13] was to define a comprehensive mathematical modeling approach based on maximizing the coefficient of power (Cp) to achieve the control of the blade pitch angle and tip speed ratio (TSR), taking into account the detailed power losses in the different parts of the wind turbine. This approach is used to determine the optimal power coefficient of a wind turbine drivetrain for direct drive and gearbox configurations. A current research topic in the field of wing design is the so-called \"intelligent wings\", which change their shape depending on the wind conditions. Within this category of wing design, there are numerous approaches, including aerodynamic control surfaces or materials for smart actuators. The goal of the research [14] is to limit end loads and stresses that affect material fatigue or to increase dynamic energy absorption. The research is based on similar concepts in helicopter control and is being conducted by the Wind Energy Research Institutes. These aerodynamic control surfaces include blade tip ailerons, blade pitch control, blade roll, and boundary layer control. More complex blade shapes are possible with the introduction of new shaping technologies and materials. However, the economics of production combined with the difficulty of analyzing a complex design will determine the final blade shape.