Abstract:A method for preprocessing tip-timing signals that does not require a once-per-revolution (OPR) sensor is proposed.The method measures the difference in the blades vibration displacement when it arrives at different tip-timing sensors to identify the blades vibration parameters and the rotational speed of the rotor.Error analysis indicates that the method can reduce the rotational speed measurement error and its impact on the vibration displacement measurement.The measurement error of the difference in vibration displacement is analyzed and compared with the method that requires an OPR sensor.Experiment results show that the method is feasible for BTT signal preprocessing without an OPR sensor and is very accurate.
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