Functional Safety in Wind Power

How is functional safety guaranteed? And where is it defined? Functional safety refers to a cross-sectional topic that is addressed in the most varied of standards and directives that apply to general mechanical engineering and therefore also to wind turbines. For this reason, all machines distributed within Europe are subject to the European 2006/42/EC Directive on Machinery. Specific directives pertaining to the design of wind turbines may represent a further fundamental component when it comes to a safe wind turbine. The GL 2010 Germanischer Lloyd guideline can be mentioned as an example here. In terms of safety controls (SRP/CS) within the scope of protection measures, the Machine Control Standard takes effect and requires the risk assessment of systems, amongst other factors. And ultimately, IEC 61508 is also to be heeded with respect to safety-related control systems. The last mentioned two ordinances here work on the basis of the stipulation of the probability of a dangerous failure (MTT Fd value/PFHd value). In order to meet functional safety requirements, a risk assessment and, where applicable, risk minimization of safety functions are of relevance. This results in two categories in line with which a risk assessment can be carried out.

• Performance Level PLx in conformity with ISO 13849-1, or

• Safety Integrity Level SIL X in conformity with IEC 61508

In order to calculate the relevant level, reliability values (MTT Fd value/PFHd value) are made available by us as your component manufacturer.