Fault Tolerant Control of Wind Turbine with Sensor and Actuator Faults

( Ji Yeon Kim ),( In Seok Yang ),( Don Gik Lee ) 한국센서학회 2013 센서학회지 Vol.22 No.1

This paper presents a fault-tolerant control technique for wind turbine systems with sensor and actuator faults. The control objective is to maximize power production and minimize turbine loads by calculating a desired pitch angle within their limits. Any fault with a sensor and actuator can cause significant error in the pitch position of the corresponding blade. This problem may result in insufficient torque such that the power reference cannot be achieved. In this paper, a fault-tolerant control technique using a robust dynamic inversion observer and control allocation is employed to achieve successful pitch control despite these faults in the sensor and actuator. The observer based detection method is used to detect and isolate sensor faults by checking whether errors are larger than threshold values. In addition, the control allocation technique is adopted to tolerate actuator fault. Control allocation is one of the most commonly used faulttolerant control techniques, especially for over-actuated systems. Further, the control allocation method can be used to achieve the power reference even in the event of blade actuator fault by redistributing the lost torque due to erroneous pitch position into non-faulty blade actuators. The effectiveness of the proposed method is demonstrated through simulations with a benchmark model of the wind turbine.

시간지연제어기법을 이용한 헥사콥터 작동기 다중고장 허용제어

이장호,김성필,심현철 한국항공우주학회 2014 한국항공우주학회 학술발표회 논문집 Vol.2014 No.11

Multi-rotor unmanned aerial vehicles (UAV) have been adopted in many areas in recent years. If one or multiple actuators failure occurs during flight, the UAV may not be able to maintain a controlled flight or even worse, it could be crashed due to lose of control authority. Likewise, if a conventional quadrotor is subjected to a failure of a rotor, it may exhibit unacceptable performance even if fault tolerant control (FTC) method is adopted. In order to overcome the drawback of the quadrotor, the hexarotor, which has six rotors instead of four, has been developed to increase reliability and controllability even at the mechanical fault conditions such as degradation of motor performance or even worse electric motor failure. A novel attitude tacking control method using Time Delay Control (TDC) scheme is developed to provide robust controllability of a rigid hexarotor in case of single or multiple rotor faults. When the TDC scheme is developed, the rotor faults such as the abrupt and/or incipient rotor faults are considered as model uncertainties. The kinematics, modeling of rigid dynamics of hexarotor, and design of stability and controllability (SCAS) are addressed rigorously in this paper. In order to compare the developed control scheme to a conventional control method, a nonlinear numerical simulation was performed and the attitude tracking performance was compared between the two methods considering the single and multiple rotor faults cases. The developed control scheme shows superior stability and robust controllability of a hexarotor that is subjected to one or multiple rotor faults and external disturbance, i.e., wind shear, gust, and turbulence.

Fault-tolerant Trajectory Tracking Control of a Quadcopter in Presence of a Motor Fault

Davood Asadi,Karim Ahmadi,Seyed Yaser Nabavi 한국항공우주학회 2022 International Journal of Aeronautical and Space Sc Vol.23 No.1

As a part of emergency landing architecture for multi-rotor, a fault-tolerant trajectory tracking control strategy is proposed in this paper to control a quadcopter in case of a partial motor fault. The introduction of fault-tolerant strategy includes a lightweight fault detection and identification algorithm and a three-loop tracking controller. The lightweight fault detection and identification algorithm identifies the fault based on the controller outputs and the angular rates calculated by a discrete extended Kalman filter. The three-loop controller comprises a cascade structure of a discrete nonlinear adaptive algorithm in the inner-loop and a PID algorithm in the outer-loops of the controller structure. To have more realistic simulations, the gyroscopic effects of rotors and the airframe drag terms are considered in modeling as the model uncertainty. The simulation results demonstrate that the proposed fault-tolerant controller can effectively control the quadcopter in presence of partial motor fault, model uncertainties, and sensor noises. The results also demonstrate the effect of fault detection time delay on the overall control performance.

An Adaptive Fault-tolerant Robust Controller with Fault Diagnosis for Submarine’s Vertical Movement

Zhen Yu,Lijun Liu,Fei Wang 제어·로봇·시스템학회 2015 International Journal of Control, Automation, and Vol.13 No.6

In this paper, an integrated design of fault diagnosis and adaptive fault-tolerant robust control for a submarine with bow and stern plane faults is proposed. Considering the disturbance coming from waves when a submarine operates near sea surface, a simplified linear system of submarine’s vertical movement with both wave disturbance and bow and stern plane faults is presented. An unknown input observer is designed to decouple the wave disturbance and the bow and stern plane faults. Then a fault parameter tracking law is designed to estimate the bow and stern plane fault parameters without any prior fault information. Based on the estimated fault parameters, an adaptive robust fault-tolerant controller is designed. Simulation results show that the proposed control scheme has a satisfactory effect in the both pitch and depth control when the bow and stern planes suffer from unknown faults.

Steer-By-Wire 시스템의 Fault-Tolerant 기술 개발

김재석,이운성 국민대학교 생산기술연구소 2004 공학기술논문집 Vol.27 No.-

The Steer-By-Wire (SBW) system replaces complex mechanical linkages of the current steering system with electric motors, sensors, and electronic control units. However, the SBW system should guarantee its safety before commercialization, and therefore, a reliable and robust fault-tolerant technology has to be implemented. This paper presents fault-tolerant control strategy for a reliable and safe SBW system and proposes a fault-tolerant SBW control system integrating SBW control algorithms, fault-detection algorithms, and reconfiguration algorithms. Based on careful analysis on propagation effects of sensor faults, a reliable fault-tolerant control strategy has been developed. The fault-tolerant controller consists of a fault detection part that monitors and defects faults in the steering wheel and road wheel sensors, and a reconfiguration part that switches to normal sensor signal based on fault detection information. It has been demonstrated that the proposed algorithm detects sensor faults accurately and enables reliable steering control under various dynamic fault situations.

Fault Tolerant Control for an Unmanned Surface Vessel Based on Integral Sliding Mode State Feedback Control

Xiu-Ning Yu,Li-Ying Hao,Xiao-Lei Wang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.8

In the complex ocean environment, the thruster faults may affect the stability of unmanned surface vessel (USV). So it is really important to study the problem of USV fault tolerant control. Under the framework of integral sliding mode technology, this work presents a fault tolerant control problem for USV. First, a comprehensive thruster fault model with total faults, partial faults, hard-over faults, bias faults, and time-varying stuck faults, is established. Then, an integral sliding mode surface and sliding mode controller with fault estimation are designed. Through LMI technology and Lyapunov stability theory, the stability of sliding mode has been proved. Compared with the existing results, the oscillation amplitudes of yaw angle and yaw velocity can be suppressed from the every beginning. Finally, simulation results demonstrate that the proposed integral sliding mode fault tolerant control algorithm is effective.

Fault-Tolerant Control of Dual Three-Phase PMSM Based on Minimum Copper Loss Under Multi-Phase Open and Open-Switch Faults

Yan Xunzhi,Ai Sheng,Li Chushan,Mei Dan 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.5

In this paper, a fault-tolerant control strategy with minimum copper loss is proposed for open phase faults (single-phase faults and two-phase faults) and switch faults (open-switch faults) of dual three-phase permanent magnet synchronous motors (DTP-PMSM). In the traditional minimum copper loss control scheme, the sinusoidal current constraint will cause the copper loss to fail to reach the minimum target. In this paper, the corresponding VSD coordinate transformation matrix under diff erent open phase faults is derived. Secondly, based on the copper loss formula, the minimum copper loss and its corresponding non-sinusoidal current constraint are derived theoretically and the fault-tolerant control of DTP-PMSM with isolated neutral point is realized. Aiming at the switch fault, the fault-tolerant control of the switch fault is realized by making full use of the remaining healthy switch of the faulty inverter. Finally, the simulation proves that the proposed control strategy has lower copper loss than the existing control strategy.

MPC-based FTC with FDD against Actuator Faults of UAVs

Bin Yu,Youmin Zhang,Yaohong Qu 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10

The increasing development of unmanned aerial vehicles (UAVs) and the requirements of high autonomy and safety levels require that the controller of UAVs should possess fault-tolerant/reconfigurable function to accommodate unpredicted situations such as actuator faults, sensor faults, or aircraft damage. This paper addresses the partial loss of control effectiveness (LOE) of actuators in a quadrotor UAV using model predictive control (MPC) with terminal constraints, which allows to track a reference command even if in the presence of actuator faults. The proposed faulttolerant control system (FTCS) adopts MPC technique to design fault-tolerant controller and state-augmented Kalman filter (SAKF) to achieve fault detection and diagnosis (FDD) function. Simulation results based on a quadrotor UAV demonstrate that the proposed fault-tolerant controller has a good performance in accommodating actuator faults.

Fuzzy Fault-tolerant Controller With Guaranteed Performance for MIMO Systems Under Uncertain Initial State

Chun-Wu Yin,Saleem Riaz,Ali Arshad Uppal,Jamshed Iqbal 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.6

It is always problematic that the initial value of the trajectory tracking error must be inside the area included in the prescribed performance constraint function. To overcome this problem, a novel fault-tolerant control strategy is designed for a second-order multi-input and multi-output nonlinear system (MIMO-NLS) with unknown initial states, actuator faults, and control saturation. Firstly, a predefined time convergence (PTC) stability criterion is theoretically proven. Then, an error conversion function is introduced to convert the trajectory tracking error to a new error variable with an initial value of zero, and an adaptive fuzzy system is designed to approximate the compound interference composed of actuator fault, parameter perturbation, control saturated overamplitude, and external disturbance. Based on the backstepping control method, prescribed performance control method, and predefined time convergence stability theory, an adaptive fuzzy fault-tolerant controller for the new error variable is designed and theoretically proven for the predefined time convergence of the closed-loop system. The numerical simulation results of the guaranteed performance trajectory tracking control for industrial robots with actuator faults demonstrate that the adaptive fuzzy fault-tolerant control algorithm has strong fault tolerance to actuator faults and anti-interference capabilities. The convergence time and performance of trajectory tracking errors can be preset in advance, and the parameter settings of the prescribed performance constraint function are not affected by the initial state values.

Fault Tolerant Control of Hexacopter for Actuator Faults using Time Delay Control Method

Jangho Lee,Hyoung Sik Choi,Hyunchul Shim 한국항공우주학회 2016 International Journal of Aeronautical and Space Sc Vol.17 No.1

A novel attitude tacking control method using Time Delay Control (TDC) scheme is developed to provide robust controllability of a rigid hexacopter in case of single or multiple rotor faults. When the TDC scheme is developed, the rotor faults such as the abrupt and/or incipient rotor faults are considered as model uncertainties. The kinematics, modeling of rigid dynamics of hexacopter, and design of stability and controllability augmentation system (SCAS) are addressed rigorously in this paper. In order to compare the developed control scheme to a conventional control method, a nonlinear numerical simulation has been performed and the attitude tracking performance has been compared between the two methods considering the single and multiple rotor faults cases. The developed control scheme shows superior stability and robust controllability of a hexacopter that is subjected to one or multiple rotor faults and external disturbance, i.e., wind shear, gust, and turbulence.