Predictive Rotor Speed Control for Wind Turbine Over-speeding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wind turbines face challenges in preventing over-speeding due to loss of counter torque from the generator or failures in rotor blade feathering, which can lead to mechanical loading and instability, especially when aggressive braking techniques are required.
Innovation Solution
A wind turbine system that includes a control system capable of predicting over-speeding events based on current rotor acceleration and speed, and generates pitch commands for the blades to avoid such events by adjusting their pitch angles, using equations to determine the necessary pitch alterations and counter-torque margins.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If aggressive braking techniques are employed to prevent over-speeding, then rotor speed control is improved, but mechanical loading of the wind turbine increases
Solution Approach 1:
The control system predicts future rotor speed by calculating rotor acceleration and projecting it forward in time. When the predicted speed exceeds the maximum threshold, pitch commands are generated in advance to adjust blade pitch angles, creating counter-torque to prevent over-speeding before it occurs, rather than relying on aggressive braking after over-speeding is detected
Solution Approach 2:
The system applies preliminary counter-action by generating pitch commands that create aerodynamic counter-torque on the rotor blades before over-speeding occurs. This predictive approach applies opposing torque through blade pitch adjustment rather than mechanical braking, reducing mechanical loading while maintaining speed control
2Reliability
If pitch angle controls are used to manage rotor speeds, then over-speeding prevention is improved, but response time during critical events may be insufficient
Solution Approach 1:
The control system performs preliminary calculations of rotor acceleration and predicts future rotor speed at a predetermined future time. This allows the system to anticipate over-speeding events and generate pitch commands before the actual over-speeding occurs, effectively reducing the response time lag by acting in advance based on predicted conditions rather than reacting to current state
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Effectively prevents over-speeding of wind turbines by predicting and mitigating rotor speed increases through controlled pitch angle adjustments, reducing the need for aggressive braking and associated mechanical loading.
Implementation Method 1
The rotor blades transform the wind energy into rotational energy
Implementation Method 2
the generator may efficiently convert the rotational energy into electrical power
Implementation Method 3
pitch angle controls, for controlling rotor speeds
Data Source
AI summary
A wind turbine system is presented. The wind turbine system includes a wind turbine tower, a plurality of blades, a rotor supported by the wind turbine tower and rotatably coupled to the plurality of blades, a torque control device coupled to the rotor, and a control system programmed to predict an over-speeding time T of an occurrence of an over-speed rotor event based at least in part upon a current rotor acceleration and a current rotor speed, that cannot be compensated by an available counter-torque margin of the torque control device, and, in response, to generate pitch commands for the pitch angles of the plurality of blades to avoid the over-speed rotor event.