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The purpose of this paper is to identify a new and simple two‐end algorithm for fault location identification and characterization, in electrical distribution systems.

The developed diagnostic algorithm is based on a simple model of the network using a lumped parameters representation.

Test results have proved the approach to be efficient, allowing a precise fault identification and location while not requiring synchronized measures from the two ends.

There is a need for measurement systems at all MV/LV substations.

Applicability with limited investments is not possible where metering systems are not so diffused, although smart grids and DG units require such infrastructures. Moreover, utilities are quite interested in such issues, since the new required quality standards put severe constraints on faults management and clearance.

The paper presents a new and easier diagnostic algorithm for faults diagnosis in distribution systems.

The purpose of this paper is to define a new methodology for studying interconnected earthing system inside unearthed medium voltage (MV) networks.

The developed methodology is based on the division of the MV network into simpler sub‐systems and its resolution using a multiport approach.

The methodology has been applied to various situations giving precious information on the behaviour of the interconnected earthing systems. The comparison between the results of the simulations and measurements done on a really existing network has shown that the methodology is able to provide accurate results.

Some factors can influence the precision of the methodology. Indeed, for a correct simulation of the system it is necessary to know several electrical and geometrical parameters, often obtainable with difficulty.

Utilities are quite interested in this topic. The study of interconnected earthing systems in MV networks with the purpose of identifying safe extended areas named Global Earthing Systems has important management and economic consequences.

The paper presents a new analysis methodology applicable to MV networks that surpasses the limits of the analysis methodology generally applied for the study of the same topic in high voltage networks.

The purpose of this paper is to present a mathematical model for studying the effects of the interconnection through bare‐buried conductors (BBC) of the secondary substations' earthing system of an urban area.

The developed methodology is based on three main points: the solution of the transmission lines' equations for the formulation of a lumped parameters model of a BBC considering the conductive effect; the division of the distribution network into simpler sub‐systems; and the calculation of all the voltages and currents of the medium voltage (MV) network and of the earthing systems using a multiport approach.

The methodology has been applied to various situations giving precious information on the behaviour of the earthing systems interconnected by means of BBC in presence of conductive effect. The results of the simulation allow to quantify the reduction of the dangerous voltages appearing during an earth fault, in presence of interconnection between the secondary substations' earthing systems, realized by means of BBC.

Some factors can influence the precision of the methodology. Indeed, for a correct simulation of the system it is necessary to know several electrical and geometrical parameters, among all the resistivity of the soil that, often, is known with a large degree of uncertainty.

Utilities are quite interested in this topic. The study of interconnected earthing systems in MV networks with the purpose of identifying safe extended areas named global earthing systems (GES) has important management and economic consequences.

The paper presents an original lumped parameters model of the BBC, able to simulate these elements with a high accuracy, also in presence of the conductive effect, and that can be easily included in the more general model of a distribution line, in order to perform the analytical study of the GES in MV networks. The model proposed allows one to overcome the limits of the application to the MV networks of similar models present in the literature for the study of the same topic in the high‐voltage networks.