Abstract
This paper is concerned with bump-less transfer of parameterized disturbance observer
based controller with individual pitch control strategy to reduce cyclic loads of wind turbine in
full load operation. Cyclic loads are generated due to wind shear and tower shadow effects.
Multivariable disturbance observer based linear controllers are designed with objective to reduce output power fluctuation, tower oscillation and drive-train torsion using optimal control theory. Linear parameterized controllers are designed by using a smooth scheduling mechanism between the controllers. The proposed parameterized controller with individual pitch was tested on nonlinear Fatigue, Aerodynamics, Structures, and Turbulence (FAST) code model of National Renewable Energy Laboratory (NREL)’s 5 MW wind turbine. The closed-loop system performance was assessed by comparing the simulation results of proposed controller with a fixed gain and parameterized controller with collective pitch for full load operation of wind turbine. Simulations are performed with step wind to see the behavior of the system with wind shear and tower shadow effects. Then, turbulent wind is applied to see the smooth transition of the controllers. It can be concluded from the results that the proposed parameterized control shows smooth transition from one controller to another controller. Moreover, 3p and 6p harmonics are well mitigated as compared to fixed gain DOBC and parameterized DOBC with collective pitch.
based controller with individual pitch control strategy to reduce cyclic loads of wind turbine in
full load operation. Cyclic loads are generated due to wind shear and tower shadow effects.
Multivariable disturbance observer based linear controllers are designed with objective to reduce output power fluctuation, tower oscillation and drive-train torsion using optimal control theory. Linear parameterized controllers are designed by using a smooth scheduling mechanism between the controllers. The proposed parameterized controller with individual pitch was tested on nonlinear Fatigue, Aerodynamics, Structures, and Turbulence (FAST) code model of National Renewable Energy Laboratory (NREL)’s 5 MW wind turbine. The closed-loop system performance was assessed by comparing the simulation results of proposed controller with a fixed gain and parameterized controller with collective pitch for full load operation of wind turbine. Simulations are performed with step wind to see the behavior of the system with wind shear and tower shadow effects. Then, turbulent wind is applied to see the smooth transition of the controllers. It can be concluded from the results that the proposed parameterized control shows smooth transition from one controller to another controller. Moreover, 3p and 6p harmonics are well mitigated as compared to fixed gain DOBC and parameterized DOBC with collective pitch.
Original language | English |
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Article number | 1296 |
Journal | Energies |
Volume | 11 |
Issue number | 5 |
Pages (from-to) | 1-13 |
Number of pages | 13 |
ISSN | 1996-1073 |
DOIs | |
Publication status | Published - 2018 |
Keywords
- wind energy conversion system (WECS)system (WECS); linear parameter varying (LPV); disturbance observer based control (DOBC); individual pitch control (IPC); load mitigation; cyclic load; linear control
- linear parameter varying (LPV)
- disturbance observer based control (DOBC)
- individual pitch control (IPC)
- load mitigation
- cyclic load
- linear control