Verification tests for DTS system measure and calculate power cable temperature

This paper describes a verification tests for qualified DTS system. The verification tests firstly focused on power cable surface temperature measurement accuracy, positional accuracy and spatial resolution accuracy. Then the power cable conductor temperature calculation which was carried out by DTS system was also verification tested. The 220kV power cable laying in tunnel and applying different load currents, the power cable conductor temperature measured value and the DTS system calculated value were compared. The testing process employs the T-type thermocouple measurement system dedicated for conductor temperature measure, DTS system calculates the conductor temperature according to load current, over-sheath temperature etc., Then analyzed and compared the difference between measured and calculated value, to verify the accuracy of the DTS system.