WIND TURBINE YAWING CONTROL TECHNIQUE
Publication Date: 2013-Sep-12
The IP.com Prior Art Database
The present invention provides a technique for systematic and site specific optimization on yawing control parameters to maximize annual energy production (AEP) within load envelopes and pad wear out limitations. The technique includes self-adjusting yawing parameter setting based on site specific condition or season. The yawing parameter automatically optimizes along with ongoing operation at one specific site. AEP is maximized with yaw load design envelope and acceptable yaw pad wear out. The technique is applicable to optimize yaw pad wear out by reducing yawing time when wind time or season are low without affecting AEP.
The present invention relates generally to a wind turbine and more particularly to optimization of yaw control parameters in the wind turbine.
Generally, a yaw system in a wind turbine ensures tracking of wind direction to capture maximum wind energy. The yaw system of wind turbines includes control parameters responsible for orientation of wind turbine rotor towards wind. Some control parameters in yaw system allow tracking wind direction. Control parameters to track wind direction is used to define delay time prior to yaw system responding to wind direction change. The defined delay time prior to yaw system response reduces unnecessary load and yaw friction pad wear out rate for operation of over twenty years. Wind turbines installed across different sites have different wind direction stability level. Therefore, defining yawing parameters setting is dynamically based on condition which is site specific or season specific. Yawing parameter setting allows maximizing annual energy production (AEP) using faster wind track by yawing system. The yawing system has limitation of load envelope and pad wear out. Conventional yawing control parameters are simplified and fixed since, wind direction stability level across sites are quite different. However, fixed yawing control parameters setting does not balance AEP and design envelope across different wind conditions.
A conventional technique includes reducing peak load of wind turbines with changing wind environment. The technique further includes comparing yaw error to yaw error trigger that has different values at different wind speed. When yaw error exceeds yaw error trigger corresponding to measured or instantaneous wind speed, the wind turbine trips down. However, the technique aims only on peak load reduction and performs inefficient protection by tripping down turbine. Tripping on smaller yaw deviation to avoid peak load is not preferable due to less AEP or availability impact.
It would be desirable to have a simple and effective technique to maximize AEP within load envelopes and pad wear out limitations.
BRIEF DISCRIPTION OF THE DRAWING
Figure 1 is a graph that depicts percentage of yawing time per wind speed bin for calculation of yaw load.
Figure 2 depicts yawing control parameter for automatic update per site data statistic.
Figure 3 depicts a flow chart for automatic update of yawing control parameter.
Table 1 depicts yaw parameter dynamic setting at different wind season.
Table 2 depicts yaw parameter dynamic setting at different operation phase.
The present invention provides a technique for systematic and site specific optimization on yawing control parameters to maximize annual energy production (AEP) within load envelopes and pad wear out limitations. The technique includes self-adjusting yawing parameter setting based on site specific condition or season. The yawing parameter automatically optimizes along with ong...