Patent ID: 7108477

Claim:
A method for determining a warning regarding a surge limit for a turbocompressor or of blade damage to a rotor in a turbomachine, the method comprising: determining at least two measurement signals each of which corresponds respectively to an output signal of one of at least two sensors which are arranged offset with respect to one another in a circumferential direction of the turbocompressor or of the rotor, said sensors being temperature, pressure or flow velocity sensors; calculating a periodicity value from at least one of the measurement signals, which periodicity value indicates a measure for occurrence of periodic signal level changes in the at least one measurement signal for a predetermined first time offset; calculating a correlation value from the at least two measurement signals, which correlation value indicates a measure for similarity of the at least two measurement signals to one another for a predetermined second time offset; and determining the warning based on the periodicity value and the correlation value.