【作者】 李涵；

【导师】 杨理践；

【作者基本信息】 沈阳工业大学 ， 测试计量技术及仪器， 2008， 硕士

【摘要】 在信息化社会的今天,光缆作为信息的载体在国民经济中发挥者越来越重要的作用。光缆一旦破损将造成巨大的损失。一个完整的光缆监测系统应包含光纤纤芯自动监测;光缆护套对地绝缘自动监测;接头盒进水的自动监测三个方面。光缆用于传输数据的部分是光纤,根据专家的经验光缆绝缘层的破损和接头盒进水是导致光纤损伤的主要原因。因此光缆绝缘层破损和接头盒进水情况的监测对光缆的日常维护非常重要。目前对光缆绝缘层破损情况衡量的主要指标是光缆绝缘层的对地电阻。现在国内主要采取使用人工到各个分站点测量绝缘电阻的方式,费时费力且无法做到实时预报。光缆破损状况在线监测系统是一套用来自动检测光缆绝缘电阻,接头盒湿度的系统。国际上只有英国雷迪公司有同类应用于工程的产品但是价格过高,无法大规模使用,国内在这方面还没有成形的技术。光缆破损在线监测系统可以测量光缆的绝缘电阻,并把测量数据上传到监测中心进而对光缆的破损情况做出早期的判断。监测系统主要包括绝缘电阻测量,控制,和数据传输三个部分,本文主要研究了绝缘电阻测量的相关电路的测量高压生成电路,绝缘层放电电路及取样电路,控制电路的上电阶段继电器触发控制电路,处理器对系统控制的接口电路。由于设计指标苛刻本文所设计电路中大量使用分离件而非集成芯片,电路设计过程中大量使用Pspice仿真辅助设计,大大的方便了电路的设计。所设计电路经调试后,测量高压生成电路使用26V左右的系统电压产生250V用于绝缘电阻测量的标准高压;上电阶段继电器触发控制电路可以在指标要求环境下,使继电器在规定电压及电流下正常触发并在系统供电后接受处理器控制;其余电路也都工作正常达到了设计要求。更多还原

【Abstract】 In the information society of today, the optic cable as an information carrier in the national economy became play an increasingly important role. The damaged of optic cable will cause large enormous lost. So at this stage it is urgent to need an automation optic cable breakage monitoring system. A complete monitor system should include three aspects, the cable fiber core automatic monitoring; optic cable sheath insulation resistance automatic monitoring; joint box flooded automatic monitoring. What optical cable used for the transmission of data is optical fiber, according to the experience of experts, insulating layer of fiber optic cable and connector boxes of damaged water is the main reason for fiber damage. The monitor of cable insulation layer damage and the flood of joint box is very important to the cable maintenance.At present the key to weigh the defect of cable insulation layer is to measure the resistance of cable insulation layer. Now the major domestic method is that use artificial get every joint box and measure insulation resistance, but it is time-consuming effort and can not do real-time forecast. Cable damaged situation on-line monitoring system is used to detect a cable insulation resistance and the humidity of joint box automatically. Radiation company of Britain is the only who have a similar product, but it is too high for the engineer used, and it isn’t suit for large-scale use in domestic. Cable damage situation on-line monitor system can measure optic cable insulation resistance and then afford measurement data to monitoring centre. Then monitoring centre estimate the dilapidated conditions of the optic cable for early judgement.Monitoring systems include three part include insulation resistance measurement, control, and data transmission. This paper will research high-voltage generation circuit used for measure insulation resistance, insulating layer discharge circuit, the sampling circuit, the relay trigger control circuit of power on stage, the interface circuit for processor control system. In this paper the design indicators harsh circuit designed by the large-scale use of separation rather than integrate circuit. During the circuit design process I usually use EDA software Pspice which take greatly facilitate for the design of the circuit. After debug, the circuit generate 250V voltage used for insulation resistance measurement by 26V system power supply voltage. Relay control circuit of power on stage which make relay trigger under the normal current and voltage in provision circumstances of relay. And control by the processor after power supply of the system work. The remain circuits are working properly satisfy the design requirements.更多还原