New pulsation protection system for gas turbines based on an advanced algorithm for the identification of acoustic modes
Publication Date: 2012-Mar-31
The IP.com Prior Art Database
High amplitude pressure pulsations in gas turbines are a major issue because they limit the operating range or cause structural damage. To monitor the pulsations inside the combustor and ensure save operation pressure transducers, e.g., based on the piezo-electric effect or microphones, are used. If the pulsation amplitudes exceed the limits, for instance, due to a change in ambient conditions or the engine caused by ageing of engine components, the operation point has to be adapted or in the worst case the engine has to be shut down. Up to now, pulsation protection concepts of gas turbines are commonly based upon one pressure sensor only. In a recent ALSTOM patent application – EP 1688671 A1 – a pulsation protection system is disclosed. However, it exactly suffers from above described shortcoming of taking only one microphone. The current patent can be seen as a more general solution satisfying all possible acoustic conditions. In practice, the number of microphones is limited due to several reasons. Therefore, a protection concept is developed that relies on two pressure sensors only.