Measurement of the grounding system impedance of a substation or power plant is often required immediately after construction, in order to verify that the design calculations correctly predict the performance of the system. Years later, new measurements are sometimes required to check that the performance of the grounding system has not deteriorated. This type of measurement, however, which is ...

The grounding grid design must be made in such a way that the fundamental parameters do not exceed the safety limits. The estimation of the values of the grid resistance, the touch voltage and the step voltage is carried out by means of formulas and algorithms based on the average potential methods. In this framework, the average potential is often obtained taking into account the mutual influe...

This paper starts with an overview of the common grounding techniques used in distribution grids. Next some important issues and problems related to grounding of distributed generators implemented in these grids will be described. Two applications will be discussed in detail: UPS systems and microgrids. The presence of a neutral conductor in these systems and the ability to operate both in grid...

Sensitivity analysis of a power system against overvoltage was performed. The analysis took into account the origin of the overvoltage, the grounding resistance magnitude and overvoltage injection point. The IEEE 13 bus test feeder system was implemented in EMTP-ATP and lightning and switching overvoltages were applied. Three cases were evaluated: the first one, applying lightning overvoltage a...

1. Abstract This paper focuses on two problems related to establishing common ground in different modes of communication. The paper reviews publications that explore grounding with relation to humanhuman interaction, in both verbal interaction and common grounding in vision based interaction. With verbal and vision as the first level premise, this paper also discusses issues on grounding that c...

In order to equalize the electric potential distribution of the grounding grid surface, and improve the safety level of the grounding grid, method for optimal arrangement of conducts in the grounding grid is proposed in this paper. The calculation results about maximum touch voltages and mesh potentials show that the method can reduce touch voltage and equilibrium surface potential. It is shown...

Grounding provides safety and in some cases a return circuit for load currents and also an uniform distribution of the voltage on the surface of the earth at power plants. If grounding conductors are damaged, it may cause unintended protective relay operation causing feeders to be tripped. It can also result in failure of the grounding device itself, secondary circuits’ cables and structural el...

This paper argues that for the study and facilitation of collaborative learning, existing theories of grounding such as that of Clark and Shaefer [5] cannot be applied without adjustments. When comparing collaborative learning and conversation, four dimensions can be identified where grounding at a knowledge level differs from the grounding at an utterance level. Firstly, the indirect access an...

Event grounding aims at linking mention references in text corpora to events from a knowledge base (KB). Previous work on this task focused primarily single KB event, thereby overlooking the hierarchical aspects of events. Events documents are typically described various levels spatio-temporal granularity. These relations utilized downstream tasks narrative understanding and schema construction...