Motor displacement sensor based on eddy current principle

Abstract

The invention discloses a motor displacement sensor based on an eddy current principle, relates to the technical field of displacement sensors, and provides the following scheme that the motor displacement sensor comprises a probe of the sensor, an extension cable and a front-end device, the probe is connected with the front-end device through the extension cable, the detection end of the probe is close to a detected object, and the probe is connected with the front-end device through the extension cable. A probe coil is arranged at the front end of the probe, the probe is formed by winding an enameled copper wire on a probe framework, the probe framework is made of a polytetrafluoroethylene material due to the requirement of the electromagnetic property of the probe coil, and the probe coil is arranged in a shell made of stainless steel. And an extension cable for connecting the sensor probe and the front-end device is a high-temperature-resistant radio frequency cable. The design of the sensor is mainly based on the eddy current principle, meanwhile, a resonance circuit and a differential circuit are utilized to improve the anti-interference performance, measurement results are further processed through filtering and linear compensation, and most of the prior art cannot meet the complex detection requirements.

Description

technical field [0001] The invention relates to the technical field of displacement sensors, in particular to a motor displacement sensor based on the principle of eddy current. Background technique [0002] In real life, the eddy current principle is widely used, mainly focusing on its thermal effect (such as an induction cooker). Eddy current detection technology is an emerging detection technology based on the principle of electromagnetic induction, and eddy current sensor is a sensor based on this detection technology. Compared with the traditional displacement ranging sensor, the eddy current sensor has the advantages of non-contact ranging, no pollution, high efficiency and good performance, so it has a broad development prospect. [0003] The basic principle is: through the coupling circuit between the coil and the conductor under test established by the equivalent idea, it can be known that when a high-frequency alternating current is applied to the detection coil, ...

AI Technical Summary

Problems solved by technology

[0006] Disadvantages of the existing technology: the eddy current displacement sensor under the current technical conditions mainly measures the relatively obvious displacement change, and simply extracts the amplitude and phase of the input signal. If this type of sensor is applied to measure the radial offset of the motor rotor , its measurement accuracy and sensitivity for small displacements are not up to the requirements. The ultimate goal of eddy current ranging is to realize the regulation of the rotor position of the motor. The independent measurement results do not have practical significance. Processing (such as filtering, linear compensation, etc.), most of the existing technologies cannot meet these more complex detection requirements

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