# Height Control System for Wind Turbines Based on Critical Wind Speed Calculation
## 1 Introduction  
The steady demand for electrical energy in the world and environmental issues in that regard, especially the transition to fossil-free energy production, demand the active development of renewable energy production systems. Hereby, wind turbines play a key role in this process, providing fossil-free energy production. However, with the increasing number of wind turbines deployed in the field, the frequency of turbine failures due to strong wind gusts has also increased significantly [1]. One of the widely used control strategies in wind turbine management is the Proportional-Integral-Derivative (PID) controller. PID control technology has been a cornerstone in industrial automation for many decades due to its simplicity, reliability, and ease of implementation [2]. Despite its prevalence, the performance of PID controllers in highly dynamic environments like wind turbines can be limited [3]. These limitations arise due to the inherent delay and overshoot that PID controllers may experience under fast-changing wind conditions, leading to less precise control during gusty or turbulent events. Nonetheless, the continued use of PID control in wind turbine applications, including the Onipko rotor system, is driven by its low computational requirements and ease of tuning, which make it a cost-effective solution for many installations. This advantage is especially significant in resource-constrainedenvironments where more advanced controllers, such as Model Predictive Control (MPC), could introduce prohibitive costs in terms of both hardware and skilled personnel [4]. The introduction of new rotor models and technological advancements, while aimed at improving efficiency, has inadvertently heightened the risks associated with extreme weather conditions [5]. These risks include structural failures and increased maintenance costs due to the susceptibility of sophisticated components to damage under severe wind stress. Specifically, the vertical axis and lightweight design of the Onipko rotor contribute to uneven load distribution during high wind conditions, resulting in increased oscillations and potential rotor displacement, which can cause damage to the support structure and the main shaft bearings. To address these challenges, advanced control systems have been developed to ensure the safe and reliable operation of wind turbines during high wind events. In the context of the Onipko rotor, the use of a PID controller remains a practical choice due to its ability to provide reliable, albeit less sophisticated, control in managing rotor position and reducing mechanical stress. While more advanced control techniques offer superior performance in certain conditions, the robustness and simplicity of PID control make it suitable for managing the balance between cost and performance [6]. Despite these solutions, limitations in structural design remain, such as the lack of flexibility in the rotor blades, making them vulnerable to fatigue and possible detachment under extreme wind pressure. Implementing these control solutions helps to manage loads on turbine structures, minimize damage, and reduce the number of failures in extreme conditions. A study conducted in [7] shows that wind turbine blades are particularly susceptible to damage due to variable loads, especially under strong wind conditions. For example, the frequency of cracks at the blade tips is 77.78%, and in the middle parts of the blades, it is 22.22% [8]. Furthermore, an analysis of wind turbine equipment revealed that harsh operating conditions and long operational cycles significantly affect the reliability and maintenance costs of wind turbines [9]. To reduce the number of failures and increase the resilience of wind turbines to extreme weather conditions, new materials and technologies are being developed, such as advanced composite materials and active load control systems [10].