On-line rotor and stator axial clearance measuring device based on dual-wavelength sweep frequency intensity modulation

Abstract

The invention discloses a rotor and stator axial clearance online measurement device based on dual-wavelength sweep frequency intensity modulation. The rotor and stator axial clearance online measurement device comprises a secondary modulation light path unit, a measurement light path and reference light path unit, a sweep frequency signal generation unit and a data acquisition and processing unit, the secondary modulation light path unit is composed of a first laser, a second laser, a coupler, an isolator, a first electro-optic intensity modulator, a circulator, a first wavelength division multiplexer, a second electro-optic intensity modulator and a second wavelength division multiplexer. The data acquisition and processing unit consists of a first detector, a second detector, a first acquisition card, a second acquisition card and a PC (Personal Computer) upper computer; the method is an optical measurement method based on laser emission and optical fiber transmission, and is suitable for a measurement environment with a complex signal leading-out path in the aero-engine, the laser is transmitted in the aero-engine, compared with an electric signal, the laser is not easily interfered by electromagnetic interference, and the current situation that no mature rotor and stator axial gap measurement scheme exists at home and abroad is broken through.

Description

technical field [0001] The invention relates to the field of non-contact distance measurement, in particular to the field of axial gap measurement of aero-engine rotor and stator. Specifically, the present invention relates to an on-line measurement method and device for rotor-stator axial gap based on dual-wavelength (or multi-wavelength) swept frequency intensity modulation. Background technique [0002] When major equipment is in operation, the inside of the machine is under extremely harsh conditions such as high temperature (above 600°C) and high vibration, and its internal space is narrow and the structure is complex. Traditional measurement methods cannot meet the requirements of on-line dynamic sensing and measurement of gaps. How to achieve highly reliable, high-resolution, and high-precision online dynamic measurement of gaps in narrow spaces and high temperatures is a key scientific and technical problem that needs to be solved urgently. [0003] At present, the ...

AI Technical Summary

Problems solved by technology

[0004] The capacitance method has the characteristics of high temperature resistance, fast response speed, and good reliability, but the size of the probe will increase sharply with the increase of the measurement range, and due to the temperature characteristics of the medium, the temperature drift of the measurement results is large; the eddy current method It has the advantages of being resistant to harsh environments such as water vapor and oil pollution, and can measure the gap in a heavily polluted environment. The leakage capacitance, leakage conductance and other parameters of the eddy current sensor are significantly affected by temperature changes, and even cause circuit saturation in severe cases, resulting in measurement failure; the microwave method is not easily affected by the internal working environment of the engine, and is suitable for the measurement of tiny gaps in the engine, but the current temperature The problem of drift compensation has not been effectively solved. In addition, due to the use of high-frequency microwaves and high-temperature mineral cables, the transmission loss is relatively large, so it is not suitable for use in the measurement environment of narrow spaces inside major equipment, long distances, and complex lead-out paths.

Images