Pioneer earth systems remote monitoring for secondary distribution substations

Abstract

EDP Distribuição is currently focusing on implementing sensorization solution for its assets, having in mind their importance for the grid operation, their financial value and their maintenance needs. This strategy, conjugated with the comparison between Portuguese regulation regarding maintenance of secondary distribution substations and the regulation of other similar European countries, are the support basis for the system implementation here described. The system uses a sensor to measure the earthing system impedance values of the secondary distribution substations, allowing the online monitoring of these values through a Remote Supervision System. With this, it is possible to register and analyse the values of the earthing systems and their variability throughout the year, which results in a more precise knowledge of the asset condition, supporting the possibility to shift the maintenance strategy from Preventive do Predictive. Furthermore, by studying and comparing the measurements of the earthing systems registered with this solution with the ones registered with the regulated method, it shows that different methods can be used to perform these measurements accurately.