110 / 2022-03-13 17:24:30

Implementation of temperature monitoring for MV cables based on signal propagation

Temperature monitoring,medium voltage power cable,travelling waves,dielectric permittivity

Medium-Voltage power cables are generally not monitored based on their temperature. At present the capacity of these cables are not fully utilized. Nevertheless, temperature monitoring could become more urgent as the energy transition results in increasing need for transmission and distribution of electric power. This paper describes the implementation of temperature monitoring based on the temperature dependent wave velocity of injected signals.

Measurements are performed on XLPE and PILC insulated cables as function of temperature. The shift in the far end reflection patterns is determined. This shift will be compared with the shift modelled from the temperature dependency of the relative permittivity.

The signal delay for PILC cables allows for an accurate temperature monitoring, whereas for XLPE, the main shift occurs only when reaching its maximum operating temperature. For proper interpretation a comparison with a reference waveform is needed taken at ambient temperature.

Temperature monitoring based on wave propagation is a non-intrusive option for MV cables, which are suspected from high loading. It can be implemented in existing connections.