Optimal Pitch Control Design With Disturbance Rejection for the Controls Advanced Research Turbine

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
David Wenzhong Gao ◽  
Xiao Wang ◽  
Jianhui Wang ◽  
Tianqi Gao ◽  
Margareta Stefanovic ◽  
...  
Keyword(s):  
Steady State ◽  
Wind Turbine ◽  
Feedforward Control ◽  
State Regulation ◽  
Rotor Speed ◽  
Coupled Modes ◽  
Control Approach ◽  
Pitch Control ◽  
Model Based ◽  
The Impact

Advanced and model-based control techniques have become prevalent in modern wind turbine controls in the past decade. These methods are more attractive compared to the commonly used proportional-integral-derivative (PID) controller, as the turbine structural flexibility is increased with multiple and coupled modes. The disturbance accommodating control (DAC) is an effective turbine control approach for the above-rated wind speed region. DAC augments the turbine state-space model with a predefined disturbance waveform model, based on which the controller reduces the impact of wind disturbances on the system output (e.g., rotor speed). However, DAC cannot completely reject the wind disturbance in certain situations, and this results in steady-state regulation errors in the turbine rotor speed and electric power. In this paper, we propose a novel wind turbine pitch control using optimal control theory. The obtained feedback and feedforward control terms function to stabilize the turbine system and reject wind disturbances, respectively, derived systematically based on the Hamilton–Jacobi–Bellman (HJB) equation. Simulation results show that the proposed method achieves desired rotor speed regulation with significantly reduced steady-state errors under turbulent winds, which is simulated on the model of the three-bladed controls advanced research turbine (CART3) using the FAST code.

scholarly journals Development of Hardware-in-the-Loop-Simulation Testbed for Pitch Control System Performance Test

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 2031
Author(s):  
Jongmin Cheon ◽  
Jinwook Kim ◽  
Joohoon Lee ◽  
Kichang Lee ◽  
Youngkiu Choi
Keyword(s):  
Control System ◽  
Wind Speed ◽  
Wind Turbine ◽  
Wind Shear ◽  
Performance Test ◽  
Control Function ◽  
Hardware In The Loop ◽  
Rotor Speed ◽  
Test Bed ◽  
Pitch Control

This paper deals with the development of a wind turbine pitch control system and the construction of a Hardware-in-the-Loop-Simulation (HILS) testbed for the performance test of the pitch control system. When the wind speed exceeds the rated wind speed, the wind turbine pitch controller adjusts the blade pitch angles collectively to ensure that the rotor speed maintains the rated rotor speed. The pitch controller with the individual pitch control function can add individual pitch angles into the collective pitch angles to reduce the mechanical load applied to the blade periodically due to wind shear. Large wind turbines often experience mechanical loads caused by wind shear phenomena. To verify the performance of the pitch control system before applying it to an actual wind turbine, the pitch control system is tested on the HILS testbed, which acts like an actual wind turbine system. The testbed for evaluating the developed pitch control system consists of the pitch control system, a real-time unit for simulating the wind and the operations of the wind turbine, an operational computer with a human–machine interface, a load system for simulating the actual wind load applied to each blade, and a real pitch bearing. Through the several tests based on HILS test bed, how well the pitch controller performed the given roles for each area in the entire wind speed area from cut-in to cut-out wind speed can be shown.

scholarly journals Fault Tolerant Control of Internal Faults in Wind Turbine: Case Study of Gearbox Efficiency Decrease

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Younes Ait El Maati ◽  
Lhoussain El Bahir ◽  
Khalid Faitah
Keyword(s):  
Steady State ◽  
Wind Turbine ◽  
Wind Turbines ◽  
Fault Tolerant ◽  
Fault Tolerant Control ◽  
Operating Point ◽  
Rotor Speed ◽  
Integral Term ◽  
Internal Faults

This paper presents a method to control the rotor speed of wind turbines in presence of gearbox efficiency fault. This kind of faults happens due to lack of lubrication. It affects the dynamic of the principal shaft and thus the rotor speed. The principle of the fault tolerant control is to find a bloc that equalizes the dynamics of the healthy and faulty situations. The effectiveness decrease impacts on not only the dynamics but also the steady state value of the rotor speed. The last reason makes it mandatory to add an integral term on the steady state error to cancel the residual between the measured and operating point rotor speed. The convergence of the method is proven with respect to the rotor parameters and its effectiveness is evaluated through the rotor speed.

scholarly journals Computationally Inexpensive Approach for Pitch Control of Offshore Wind Turbine on Barge Floating Platform

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Shan Zuo ◽  
Y. D. Song ◽  
Lei Wang ◽  
Qing-wang Song
Keyword(s):  
Wind Turbine ◽  
Reducing Power ◽  
Uncertain System ◽  
Robust Adaptive Control ◽  
Offshore Wind ◽  
Offshore Wind Turbine ◽  
Complex Load ◽  
Control Approach ◽  
Pitch Control ◽  
System Parameters

Offshore floating wind turbine (OFWT) has gained increasing attention during the past decade because of the offshore high-quality wind power and complex load environment. The control system is a tradeoff between power tracking and fatigue load reduction in the above-rated wind speed area. In allusion to the external disturbances and uncertain system parameters of OFWT due to the proximity to load centers and strong wave coupling, this paper proposes a computationally inexpensive robust adaptive control approach with memory-based compensation for blade pitch control. The method is tested and compared with a baseline controller and a conventional individual blade pitch controller with the “NREL offshore 5 MW baseline wind turbine” being mounted on a barge platform run on FAST and Matlab/Simulink, operating in the above-rated condition. It is shown that the advanced control approach is not only robust to complex wind and wave disturbances but adaptive to varying and uncertain system parameters as well. The simulation results demonstrate that the proposed method performs better in reducing power fluctuations, fatigue loads and platform vibration as compared to the conventional individual blade pitch control.

scholarly journals Modeling and Control of Combustion Phasing in Dual-Fuel Compression Ignition Engines

2018 ◽  
Vol 141 (5) ◽  
Author(s):  
Wenbo Sui ◽  
Jorge Pulpeiro González ◽  
Carrie M. Hall
Keyword(s):  
Steady State ◽  
Control Method ◽  
Feedforward Control ◽  
Control Strategies ◽  
Combustion Process ◽  
Open Loop ◽  
Integral Model ◽  
Dual Fuel ◽  
Complex Method ◽  
Model Based

Dual-fuel engines can achieve high efficiencies and low emissions but also can encounter high cylinder-to-cylinder variations on multicylinder engines. In order to avoid these variations, they require a more complex method for combustion phasing control such as model-based control. Since the combustion process in these engines is complex, typical models of the system are complex as well and there is a need for simpler, computationally efficient, control-oriented models of the dual-fuel combustion process. In this paper, a mean-value combustion phasing model is designed and calibrated, and two control strategies are proposed. Combustion phasing is predicted using a knock integral model (KIM), burn duration (BD) model, and a Wiebe function, and this model is used in both an adaptive closed loop controller and an open loop controller. These two control methodologies are tested and compared in simulations. Both control strategies are able to reach steady-state in five cycles after a transient and have steady-state errors in CA50 that are less than ±0.1 CA deg (CAD) with the adaptive control strategy and less than ±1.5 CAD with the model-based feedforward control method.

scholarly journals Cylinder-specific model-based control of combustion phasing for multiple-cylinder diesel engines operating with high dilution and boost levels

2018 ◽  
Vol 21 (7) ◽  
pp. 1231-1250
Author(s):  
Wenbo Sui ◽  
Carrie M Hall ◽  
Gina Kapadia
Keyword(s):  
Steady State ◽  
Diesel Engines ◽  
Specific Model ◽  
Integral Model ◽  
Loop Control ◽  
Model Based Control ◽  
Model Based ◽  
Crank Angle Degree ◽  
Crank Angle ◽  
The Impact

Accurate control of combustion phasing is indispensable for diesel engines due to the strong impact of combustion timing on efficiency. In this work, a non-linear combustion phasing model is developed and integrated with a cylinder-specific model of intake gas. The combustion phasing model uses a knock integral model, a burn duration model, and a Wiebe function to predict CA50 (the crank angle at which 50% of the mass of fuel has burned). Meanwhile, the intake gas property model predicts the exhaust gas recirculation fraction and the in-cylinder pressure and temperature at intake valve closing for different cylinders. As such, cylinder-to-cylinder variation of the pressure and temperature at intake valves closing is also considered in this model. This combined model is simplified for controller design and validated. Based on these models, two combustion phasing control strategies are explored. The first is an adaptive controller that is designed for closed-loop control and the second is a feedforward model–based control strategy for open-loop control. These two control approaches were tested in simulations for all six cylinders, and the results demonstrate that the CA50 can reach steady-state conditions within 10 cycles. In addition, the steady-state errors are less than ±0.1 crank angle degree with the adaptive control approach and less than ±1.3 crank angle degree with feedforward model–based control. The impact of errors on the control algorithms is also discussed in the article.

scholarly journals Disturbance Accommodating Control Design for Wind Turbines Using Solvability Conditions

2017 ◽  
Vol 139 (4) ◽  
Author(s):  
Na Wang ◽  
Alan D. Wright ◽  
Mark J. Balas
Keyword(s):  
Steady State ◽  
Wind Turbine ◽  
Wind Turbines ◽  
Kronecker Product ◽  
Solvability Condition ◽  
Control Design ◽  
Rotor Speed ◽  
Solvability Conditions ◽  
Speed Regulation ◽  
Disturbance Accommodating Control

In this paper, solvability conditions for disturbance accommodating control (DAC) have been discussed and applied on wind turbine controller design in above-rated wind speed to regulate rotor speed and to mitigate turbine structural loads. An asymptotically stabilizing DAC controller with disturbance impact on the wind turbine being totally canceled out can be found if certain conditions are fulfilled. Designing a rotor speed regulation controller without steady-state error is important for applying linear control methodology such as DAC on wind turbines. Therefore, solvability conditions of DAC without steady-state error are attractive and can be taken as examples when designing a multitask turbine controller. DAC controllers solved via Moore–Penrose Pseudoinverse and the Kronecker product are discussed, and solvability conditions of using them are given. Additionally, a new solvability condition based on inverting the feed-through D term is proposed for the sake of reducing computational burden in the Kronecker product. Applications of designing collective pitch and independent pitch controllers based on DAC are presented. Recommendations of designing a DAC-based wind turbine controller are given. A DAC controller motivated by the proposed solvability condition that utilizes the inverse of feed-through D term is developed to mitigate the blade flapwise once-per-revolution bending moment together with a standard proportional integral controller in the control loop to assist rotor speed regulation. Simulation studies verify the discussed solvability conditions of DAC and show the effectiveness of the proposed DAC control design methodology.

scholarly journals Evaluation of exponential moving average application to smooth the power output of wind turbine with different control modes

2021 ◽  
Vol 11 (6) ◽  
pp. 4708
Author(s):  
Dinh Chung Phan ◽  
Ngọc An Luu
Keyword(s):  
Power Control ◽  
Wind Turbine ◽  
Power Output ◽  
Average Method ◽  
Moving Average ◽  
Speed Control ◽  
Control Mode ◽  
Rotor Speed ◽  
Smoothing Factor ◽  
The Impact

This paper focused on evaluating the application of exponential moving average method into wind turbine to smooth its power output without an energy storage system or an anemometer. Wind turbine control modes including active power control mode and rotor speed control mode are considered. For each control mode, two positions of the Exponential Moving Average method in controller were compared to choose the best position. Additionally, the impact of smoothing factor on wind turbine performance was also considered to determine a reasonable value of the smoothing factor for each control mode. Simulation results in MATLAB/Simulink indicated that, for wind turbine using rotor speed control mode, the Exponential Moving Average method should be applied to reduce the variation of actual rotor speed signal while for wind turbine with the power control mode, it should be used to smooth reference power signal. From the performance of wind turbine with different smoothing factor values, we can suggest that the smoothing factor value should be set at 0.5 and 0.4 for the power control mode and the rotor speed control mode, respectively.

scholarly journals Adaptive Pitch Control of Variable-Pitch PMSG Based Wind Turbine

2019 ◽  
Vol 9 (19) ◽  
pp. 4109
Author(s):  
Jian Chen ◽  
Bo Yang ◽  
Wenyong Duan ◽  
Hongchun Shu ◽  
Na An ◽  
...  
Keyword(s):  
Wind Turbine ◽  
Model Simulation ◽  
Synchronous Generator ◽  
Parameter Uncertainties ◽  
Permanent Magnet Synchronous Generator ◽  
Control Approach ◽  
Pitch Control ◽  
Full State ◽  
Unknown Disturbances ◽  
Extracted Power

This paper presents an adaptive pitch-angle control approach for a permanent magnet-synchronous generator-based wind turbine (PMSG-WT) connecting with a power grid to limit extracted power above the rated wind speed. In the proposed control approach, a designed perturbation observer is employed for estimating and compensating unknown parameter uncertainties, system nonlinearities, and unknown disturbances. The proposed control approach does not require full state measurements or the accurate system model. Simulation tests verify the effectiveness of the proposed control approach. The simulation results demonstrate that compared with the feedback linearizing controller, conventional vector controller with proportional-integral (PI) loops, and PI controller with gain scheduling, the proposed control approach can always maintain the extracted wind power around rated power, and has higher performance and robustness against disturbance and parameter uncertainties.

scholarly journals Model-based design of a wave-feedforward control strategy in floating wind turbines

2021 ◽  
Author(s):  
Alessandro Fontanella ◽  
Mees Al ◽  
Jan-Willem van Wingerden ◽  
Marco Belloli
Keyword(s):  
Wind Turbine ◽  
Wind Turbines ◽  
Control Strategy ◽  
Feedforward Control ◽  
Effective Control ◽  
Control Input ◽  
Wave Excitation ◽  
Rotor Speed ◽  
Floating Wind Turbine ◽  
Fatigue Loads

Abstract. Floating wind turbines rely on feedback-only control strategies to mitigate the effects of wave excitation. Improved power generation and lower fatigue loads can be achieved by including information about the incoming waves into the wind turbine controller. In this paper, a wave-feedforward control strategy is developed and implemented in a 10 MW floating wind turbine. A linear model of the floating wind turbine is established and utilized to show how wave excitation affects the wind turbine rotor speed output, and that collective-pitch is an effective control input to reject the wave disturbance. Based on the inversion of the same model, a feedforward controller is designed, and its performance is examined by means of linear analysis. A gain-scheduling algorithm is proposed to adapt the feedforward action as the wind speed changes. Non-linear time-domain simulations prove that the proposed feedforward control strategy is an effective way of reducing rotor speed oscillations and structural fatigue loads caused by waves.

Adaptive State Feedback to Maximize the Power Capture and Reduce the Tower Motion of Wind Turbine in Partial Loading Operation

2015 ◽  
Author(s):  
Kaman Thapa Magar ◽  
Mark J. Balas
Keyword(s):  
Wind Speed ◽  
Wind Turbine ◽  
State Feedback ◽  
Tracking Error ◽  
Adaptive Controller ◽  
Stability And Convergence ◽  
Speed Ratio ◽  
Rotor Speed ◽  
Control Approach ◽  
Tip Speed Ratio

A direct adaptive control approach is used to track the tip speed ratio of wind turbine to maximize the power captured during the below rated wind speed operation. Assuming a known optimum value of tip speed ratio, the deviation of actual tip speed ratio from the optimum one is mathematically expressed as tip speed ratio tracking error. Since the actual tip speed ratio is not a measurable quantity, this expression for tip speed ratio tracking error is linearized and simplified to express it in terms of wind speed and rotor speed, where rotor speed can easily be measured whereas an estimator is designed to estimate the wind speed. Important results from stability and convergence analysis of the proposed adaptive controller with state estimation and state feedback is also presented. From the analysis it was observed that the adaptive disturbance tracking controller can be combined with adaptive state feedback to achieve other control objectives such as reducing the wind turbine structural loading. Hence, an adaptive state feedback scheme is also proposed to reduce wind turbine tower fore-aft and side-side motions.

Sign in / Sign up

Export Citation Format

Share Document