Abstract:
Traditional electronic sensing technologies (vibration cable, opposite type, etc.) that are used in the pump/compressor stations of oil and gas pipeline present higher false alarm rate and suffer electromagnetic interference because active sensing (power supply needed) is adopted at their front end. Therefore, a Michelson-based vibration optical fiber cable technology is proposed. It is used to measure subtle change by means of Michelson interference principle. Based on the characteristics of human invasion, this technology can distinguish normal interference from abnormal invasion by similarity matching of continuous vibrant points. The Michelson-based vibration optical fiber cable perimeter alarm system is composed of transmission optical fiber cable, sensing optical fiber cable, front-end defense module, back-end defense module, signal processing unit, perimeter alarm host and so on. This system can effectively tell the difference between normal interference and abnormal invasion since it is designed by taking human invasion into consideration, with much lower false alarm rate. Moreover, light sensors are used at the front end and no power supply is needed, so there is no interference problem. This technology presents good results in practical engineering application.