Certificate for safe emergency shutdown of wind turbines

Abstract

Abstract-To avoid damage to a wind turbine in the case of a fault or a large wind gust, a detection scheme for emergency shutdown is developed. Specifically, the concept of a safety envelope is introduced. Within the safety envelope, the system can be shutdown without risking structural damage to the turbine. To demarcate the boundary of the safety envelope, a protection certificate, is computed. To this end, a modelbased framework of barrier certificates is used. As a result, the protection certificate problem is formulated as a sum-ofsquares program with the optimisation criterion related to the volume of the safety envelope. The framework enables the inclusion of a bounded wind disturbance and the a priori known emergency shutdown procedure. For this purpose, the model of a wind turbine is developed that includes structural safety critical components.

Safety Analysis of Stochastic Dynamical Systems

“…This is similar to Wisniewski et al (2013); however, in Wisniewski et al (2013) the largest set is not necessarily obtained. The methodology exploited in this work is inspired by Korda et al (2013); Henrion and Korda (2014), which compute regions of attraction for deterministic systems via solving convex programming problems.…”

“…Due to its simple computation, the barrier certificate method has attracted much attention.The barrier certificate method has been used for verification Prajna and Rantzer (2007), for estimation of operating envelope Wisniewski et al (2013), for safe control Wieland and Allgöwer (2007), and has been combined with control barrier functions to include constraints Ames et al (2014); Romdlony and Jayawardhana (2014).…”

Optimizing Safety Supervisors for Wind Turbines using Barrier Certificates

“…This work is a continuation and extension of the results presented in Wisniewski et al [2013]. New optimization techniques are proposed and the computational complexity is reduced.…”

Review on set-theoretic methods for safety verification and control of power system

“…The initial application of barrier certificates appeared in [40] and [41]. The barrier certificate methodology is employed to design the safety supervisor such that the wind turbines can be shutdown timely in emergent conditions.…”