Active actuator fault‐tolerant control of a wind turbine benchmark model

Abstract

This paper describes the design of an active fault-tolerant control scheme that is applied to the actuator of a\ud wind turbine benchmark. The methodology is based on adaptive filters obtained via the nonlinear geometric\ud approach, which allows to obtain interesting decoupling property with respect to uncertainty affecting the\ud wind turbine system. The controller accommodation scheme exploits the on-line estimate of the actuator\ud fault signal generated by the adaptive filters. The nonlinearity of the wind turbine model is described by the\ud mapping to the power conversion ratio from tip-speed ratio and blade pitch angles. This mapping represents\ud the aerodynamic uncertainty, and usually is not known in analytical form, but in general represented by\ud approximated two-dimensional maps (i.e. look-up tables). Therefore, this paper suggests a scheme to\ud estimate this power conversion ratio in an analytical form by means of a two-dimensional polynomial, which\ud is subsequently used for designing the active fault-tolerant control scheme. The wind turbine power generating\ud unit of a grid is considered as a benchmark to show the design procedure, including the aspects of\ud the nonlinear disturbance decoupling method, as well as the viability of the proposed approach. Extensive\ud simulations of the benchmark process are practical tools for assessing experimentally the features of the\ud developed actuator fault-tolerant control scheme, in the presence of modelling and measurement errors.\ud Comparisons with different fault-tolerant schemes serve to highlight the advantages and drawbacks of the\ud proposed methodology

Fault Tolerant and Optimal Control of Wind Turbines with Distributed High-Speed Generators

“…In the above algorithm, PI-cntrl-Tg e(t) denotes the PI generator torque controller (11) in the upper partial load, TS-cntrl-beta e(t), x(t) denotes the pitch controller (12) in the full load region and FT-cntrl[T g,d (t)] represents the model-based fault tolerant control scheme using (9). Figure 8 shows a comparison between the fault-free case (n = N) and faulty case (n = 8) during rotor acceleration from cut-in to medium strong wind speed.…”

“…In [11], an FTC scheme based on adaptive filters obtained via the nonlinear geometric approach is applied to the wind turbine benchmark model. It is shown that the proposed approach allows us to obtain an interesting decoupling property with respect to uncertainty affecting the wind turbine system.…”

“…The main contribution is as follows. First, existing FTC strategies for wind turbines with single-generators such as [9][10][11] do not take into account the design freedom of multi-generator systems. In this paper, the fault accommodation is achieved by adaption of the division of the demanded torque between the healthy generators and the rotor speed dependent transition from the partial load (torque control) to the full-load region (pitch control).…”

An advanced robust fault-tolerant tracking control for a doubly fed induction generator with actuator faults

“…It is necessary to design robust control systems that are able to reduce the effect of occurring faults, and to increase the reliability and availability of such systems while providing desirable performances [14]. These latter systems are known as fault-tolerant controller (FTC) systems, as they have the capability to accommodate component faults automatically [15]. Generally, FTC systems are divided into two main groups: active and passive [16,17].…”

Fault Diagnosis and Fault-Tolerant Control of Wind Turbines via a Discrete Time Controller with a Disturbance Compensator

“…Takagi-Sugeno fuzzy-based methods for FTC for operation below rated wind speed are presented in [18]. The work in [19] presents an active FTC scheme based on adaptive methods, and a model predictive control scheme is used for FTC in [20].…”