As the switch cabinet is the key equipment in the smart grid, the temperature of its cable connector is one of the important parameters of the system. Cable connector is a weak link for reliable operation of the switch cabinet, and its performance and quality depend not only on the material of the cable connectors, but also on the production process and the size of the real-time load. Any one of these factors may cause the cable head generate heat in the switch cabinet, and if not being detected in time, the load continues to grow and the cable head temperature will rise until causing an explosion, resulting in economic losses and security risks.

        With the increasing requirements for the safe operation of electrical equipments and more investments from the national power system, intelligentization of the switch cabinet becomes imperative. A few years ago, many innovative scientific research institutes and enterprises in our country had begun the demonstration, development and promotion of intelligent switch cabinet. Initially, only the parameters like current, voltage, partial discharge, sulfur hexafluoride and so on are routinely monitored. While currently, advanced monitoring method is adopted, that is direct temperature monitoring for charged body like busbar and contact points. Therefore, the demand for intelligence is developing explosively.

        The main features of the optical fiber temperature sensing technology is that it can directly monitor the temperature of charged body, and this also makes it the most competitive technology. By virtue of the high stability of its cable transmission, extremely long lifetime of passive temperature detector, as well as advantageous comprehensive cost, optical fiber temperature sensor has become an important component of intelligent switch devices.