The Using of Insulated Fiber Bragg Grating Temperature Sensor in 35kV Switch Cabinet

Abstract

In long-period running of switch cabinet, the temperature of contact points will be rose by the big contact resistance, poor contact and longtime overloading. Overheat can cause oxidation of contact points and the increasing of contact resistance, and then the contact may be generated the spark and arc discharge. That is a bad circle. So the temperature of contact points can affect the reliability of switch cabinet. For detecting the temperature of contacts and the switch cabinet’s environment in Yanjin transformer substation, we design an Insulated FBG temperature sensor. The surveys of upper reaches indicate that the temperature of moving contact A gets the maximum 32.98°C Aug.20, 2011, the temperature of stationary contact A gets the minimum 5.75°C, and the change temperature between contacts and environment gets the maximum 2.82°C. According to relevant state regulations, the contact’s temperature of 70 °C and temperature’s changes of 35 °C in the case of environment’s temperature below 40°C are Alarm threshold value of switch cabinet.