TY - JOUR

T1 - Failure Probability Estimation of Wind Turbines by Enhanced Monte Carlo

A1 - Sichani,Mahdi Teimouri

A1 - Nielsen,Søren R.K.

A1 - Naess,Arvid

AU - Sichani,Mahdi Teimouri

AU - Nielsen,Søren R.K.

AU - Naess,Arvid

PB - American Society of Civil Engineers

PY - 2012

Y1 - 2012

N2 - This paper discusses the estimation of the failure probability of wind turbines required by codes of practice for designing them. The Standard Monte Carlo (SMC) simulations may be used for this reason conceptually as an alternative to the popular Peaks-Over-Threshold (POT) method. However, estimation of very low failure probabilities with SMC simulations leads to unacceptably high computational costs. In this study, an Enhanced Monte Carlo (EMC) method is proposed that overcomes this obstacle. The method has advantages over both POT and SMC in terms of its low computational cost and accuracy. The method is applied to a low-order numerical model of a 5 MW wind turbine with a pitch controller exposed to a turbulent inflow. Two cases of the wind turbine model are investigated. In the first case, the rotor is running with a constant rotational speed. In the second case, the variable rotational speed is controlled by the pitch controller. This provides a fair framework for comparison of the behavior and failure event of the wind turbine with emphasis on the effect of the pitch controller. The Enhanced Monte Carlo method is then applied to the model and the failure probabilities of the model are estimated to the values related to the required 50-year return period of the wind turbine.

AB - This paper discusses the estimation of the failure probability of wind turbines required by codes of practice for designing them. The Standard Monte Carlo (SMC) simulations may be used for this reason conceptually as an alternative to the popular Peaks-Over-Threshold (POT) method. However, estimation of very low failure probabilities with SMC simulations leads to unacceptably high computational costs. In this study, an Enhanced Monte Carlo (EMC) method is proposed that overcomes this obstacle. The method has advantages over both POT and SMC in terms of its low computational cost and accuracy. The method is applied to a low-order numerical model of a 5 MW wind turbine with a pitch controller exposed to a turbulent inflow. Two cases of the wind turbine model are investigated. In the first case, the rotor is running with a constant rotational speed. In the second case, the variable rotational speed is controlled by the pitch controller. This provides a fair framework for comparison of the behavior and failure event of the wind turbine with emphasis on the effect of the pitch controller. The Enhanced Monte Carlo method is then applied to the model and the failure probabilities of the model are estimated to the values related to the required 50-year return period of the wind turbine.

KW - Wind Turbine

KW - Pitch Controller

KW - Reliability Analysis

KW - Return Period

KW - Wind Turbine

KW - Pitch Controller

KW - Reliability Analysis

KW - Return Period

U2 - 10.1061/(ASCE)EM.1943-7889.0000334

DO - 10.1061/(ASCE)EM.1943-7889.0000334

JO - Journal of Engineering Mechanics

JF - Journal of Engineering Mechanics

SN - 0733-9399

IS - 4

VL - 138

SP - 379

EP - 389

ER -