Patent ID: 8337144

Claim:
A method for correcting rotating stall in a radial diffuser of a compressor, the method comprising: measuring a value representative of acoustical energy associated with rotating stall in a radial diffuser of a compressor; filtering the measured value with a first filter to obtain a first filtered value corresponding to a first stall frequency range; rectifying the first filtered value with a first rectifier to obtain a first rectified value; filtering the first rectified value to obtain a first stall energy component; filtering the measured value with a second filter to obtain a second filtered value corresponding to a second stall frequency range; rectifying the second filtered value with a second rectifier to obtain a second rectified value; filtering the second rectified value with a filter to obtain a second stall energy component; subtracting the second stall energy component from the first stall energy component to obtain a differential stall energy component; comparing the differential stall energy component to a predetermined threshold value to determine rotating stall in the compressor; and sending a control signal to adjust an operational configuration of the compressor in response to a determination of rotating stall.