Research On The Online Measurement System Of Cable Eccentricity Based On Microwave

The control and measurement for the cable eccentricity is important for the cable production. The cable eccentricity not only causes the huge waste of the material, but also affects the performance parameters. As a kind of Non Destructive Testing(NDT) of microwave is widely used in modern industry, which plays a very important role in improving the quality and the reliability of products. On-line measurement system based on Non Destructive Testing of microwave is studied in this paper.The present situation of domestic and overseas measurement system for cable eccentricity is introduced in the first part of paper. Then the paper introduces the base quality of microwave, the testing means and the application of the the general microwave.This paper focuses on the research and development of the on-line measurement system of cable eccentricity based on microwave. The whole measurement system is composed of three parts: the detection system of the microwave, signal processing circuit and the MCU controlling circuit.(1) The bridge of the microwave is set up by the magic T as the core. Judging the changing phase of the reflected signal to determine the balance of the bridge.(2) The output signal from the magic T is processed in the signal processing circuit. For every unit, mainly analyzing and designing the detector, low-noise amplifier, voltage polarity conversion circuit and so on. Some important circuits is given in the paper. (3) The MCU controlling circuit use AT89S52 as the core to control stepping motor. In the paper, the method of the self-balancing bridge is used and the position of the variable short end is changed through the MCU controlling the stepper motor. The hardware circuit and the software part is given in the paper.