Temperature Monitoring System Of High Voltage Switchgear

High voltage switchgear (HVS), one of the important equipments of power system, exerts great influence on the operation of power system safely and stably. Of all the malfunction of power system, current-carrying malfunction that caused by the bad contact occurs frequently. It can cause temperature increase, and further lead to the overheating of the high voltage switchgear, thus resulting in fire and power cut off extensively. Monitoring the contact's temperature of the HVS can discover the hidden malfunction, and in a way it ensures that the HVS work properly.After conducting the research of the temperature measuring methods both home and abroad, this paper develops the on-line monitoring device of HVS. The paper introduces the principle of the IR temperature measuring. The whole system consists of the measuring unit, the field-monitoring unit and the remote terminal unit. Every HVS has six measuring units, which are monitoring the contact's temperature of the HVS. The micro controller changes the signal of IR thermopile sensor into digital datum. At last micro controller transmits the digital datum to the field-monitoring unit. The field-monitoring unit receives the digital datum from the measuring unit and change the digital datum to the contact's temperature datum, and it can show the temperature though an LCD panel and alarm when the temperature exceed the threshold value. As a result, some field-monitoring units form Wireless Sensor Network (WSN). The field-monitoring unit sends the temperature datum to the remote terminal unit. The remote terminal unit transmits the temperature datum to the background computer. The measuring unit and the field-monitoring unit can monitor the tempeature in the filed when it don't contact with the automatization system of the transformer substation. It can monitor the contact's temperature in the field and in the remote unite when contact with the automatization system of the transformer substation. The succeeding tests proved that the temperature monitoring system of HVS was full functional.The contact's temperature is one parameter to indicate the state of the HVS, we can continue reseach the mechanical properties or insulation properties to control the faults of power system.