Fundamental frequency vibration signal restoration method for propeller

Abstract

The invention discloses a fundamental frequency vibration signal restoration method for a propeller, a voltage signal at a screw is extracted through a peak extraction method; through an eddy current calibration experiment, the acquired voltage signal at the screw is converted into a distance signal between the probe and the screw, and then the distance signal at the screw is restored into the distance signal on the whole circumference through a point reflection method in a trust region, so that a fundamental frequency vibration displacement signal is obtained. According to the invention, a new sensor does not need to be added, the rotating speed sensor which outputs a switching value in an original blade phase synchronous monitoring device is replaced, but is not limited to the use of an eddy current displacement sensor, and no matter whether the output is a digital value or an analog value, the sensor which can measure the distance between metal in a non-contact manner can be used; the vibration monitoring function is added, the optimal solution of the problem can be obtained through rapid convergence through the point reflection method in the trust region, and thus a fundamental frequency vibration signal is obtained, and guidance is provided for the automatic balance technology.

Description

technical field [0001] The invention belongs to the field of vibration monitoring of a turboprop engine, and in particular relates to a method for restoring a fundamental frequency vibration signal for a propeller based on a point reflection method in a trust region. Background technique [0002] For aircraft equipped with turboprop engines, when the aircraft is in crosswind, climb, turn, sideslip, hover, push / pull, etc., the lift force on the blades will change from a constant load to a steady-state component. With the load of the dynamic component, the dynamic component of the lift force changes periodically with the rotation frequency of the propeller shaft, and the dynamic component of the lift force of each blade will produce a changing bending moment on the propeller shaft, which is called 1P bending moment. The total bending moment after the synthesis of the 1P bending moment generated by all the blades on the propeller shaft is a stable load, which is called the prop...

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Problems solved by technology

[0008] Aiming at the problem that the automatic balancing technology applied to the turboprop engine needs to provide the fundamental frequency vibration signal, but it is difficult to add new sensors to the developed turboprop engine, the present invention proposes that the original function will not be affected without adding new sensors Under certain conditions, the speed sensor in the original blade phase synchronization device is replaced by an eddy current displacement sensor, and a method for restoring the fundamental frequency vibration signal for the propeller is provided, so as to provide the fundamental frequency vibration signal for the automatic balancing technology

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