https://onlinelibrary.wiley.com/doi/pdf/10.1002/we.2564

Review of control strategy of large horizontal-axis wind turbines yaw system

This paper is focused on design of a wind turbine optimal yaw control system based on very short-term wind predictions. The optimal controller performance is evaluated with respect to the power production maximisation and structural loads minimisation goals that are joined together in a single performance function expressing the profit of the wind turbine control system operation. Designed optimal yaw controller performance is compared to the baseline controller in the professional aeroelastic simulator GH Bladed. The results show effectiveness of the developed optimal wind turbine yaw angle controller, since it demonstrated damage equivalent loads reduction and power production increase.

/pdf/optimal-wind-turbine-yaw-control-supported-with-very-short-3os8jlq573.pdf

Optimal wind turbine yaw control supported with very short-term wind predictions

Nowadays research focus is towards the Variable speed power generation in instead fixed speed power generation in wind energy conversion system. With variable speed, there will be 20-30% increase in the energy capture compared to the fixed-speed operation. For Variable speed wind energy conversion system the maximum power point tracking (MPPT) is a very important requirement in order to maximize the efficiency. Every year a number of publications appear in various journals and conferences/seminars claiming to offer better and faster MPPT techniques for wind energy conversion system (WECS). On the other hand, wind turbines are designed to give maximum output at wind speeds around 15 m/s (30 knots or 33 mph). For stronger winds it is necessary to dissipate part of the excess energy of the wind to avoid damaging the wind turbine. So all wind turbines are designed with some power con trol mechanism. This paper provides the brief idea about the power control techniques on modern wind turbines and a comprehensive review and critical analysis of MPPT techniques, which is very helpful for present researcher and students working in this area.

/pdf/maximum-power-extraction-schemes-power-control-in-wind-4xk9gp520s.pdf

Maximum Power Extraction Schemes & Power Control in Wind Energy Conversion System

In order to capture the maximum wind energy and improve the efficiency of wind generation system, the yaw control system is researched. This system takes the initiative to windward. According to the control algorithm proposed in this paper, yaw angle is calculated by the DSP, and the drive signals of stepping motor are generated. The stepping motor is controlled by the micro-stepping control to drive the yaw mechanical device to make the wind turbine windward. Through this way, the yaw control system can track the wind direction automatically. Experimental results show that based on the proposed control algorithm and DSP control, the performance of yaw system is great and the operation precision of stepping motor is high. Therefore, the yaw system has the ability to track the wind direction quickly and exactly.

Study and implementation of a control algorithm for wind turbine yaw control system

The present invention relates to a yaw system (5) for a windmill (1), the windmill comprising a tower (2) and a nacelle (3), the tower and the nacelle being joined by the yaw system and the yaw system further comprising a bearing fixed to the tower, on which bearing the nacelle rests and slides in a yawing movement, and at least one yaw motor arranged to allow the nacelle to perform a rotary motion along the bearing, wherein the yaw system (5) further comprises control means (8) for continuously operating the at least one yaw motor in such a way that the yaw motor strives to manoeuvre the nacelle according to a set point. The invention also relates to a method for controlling the yaw of a windmill (1), comprising the steps of determining a set point for the windmill (1), calculating a yaw error based on the set point and a current alignment of the windmill, determining a size and direction of a torque based at least on the yaw error, and applying the torque to at least one yaw motor of a yaw system for turning the turbine, whereby the method also comprises the step of continuously calculating the yaw error and applying the torque in order to strive towards the set point.

Yaw system for a windmill

This paper presents the performance comparison of two different controllers for wind turbine yaw control The two controllers evaluated are a classical proportional-derivative (PD) controller and a fuzzy logic controller (FLC) The controllers were separately used to operate the teetered rotor wind turbine presently being commissioned at the University of Texas at El Paso Without an adequate dynamics model, the performance of the PD controller is not sufficient to ensure proper response in the steady state In addition, the tuning process for selecting the optimum gains of the PD controller is an ad-hoc procedure depending on the wind condition In contrast, the nonlinear nature of the FLC provides superior response to the control requirements regardless of the wind condition Field experience gained from this experiment gives adequate confidence to apply the FLC for wind turbine yaw control

R.K. Joseph

Papers

Evaluation of Classical and Fuzzy Logic Controllers for Wind Turbine Yaw Control