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Geoelectric method applied in correlation between physical characteristics and electrical properties of the soil

Filho A. M. S., Silva C. L. B., Oliveira M. A. A., Pires T. G., Alves A. J., Calixto W. P., Narciso M. G.

Transactions on Environment and Electrical Engineering

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2017

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Vol. 2, No. 2

37--44

EN

This paper presents the study of the relationship between electrical properties and physical characteristics of the soil. Measures of apparent electrical resistivity of the soil were made for different types of soil, varying moisture content gradually while maintaining a constant compaction, and then varying the compaction and relating it to a constant humidity. Development of a correlation surface is proposed in order to identify granulometry of the soil from moisture and compaction measurements. For the study of spatial variability, two areas were chosen to allow the change of moisture content and compaction in order to verify the measurement capacity of apparent electrical resistivity of the soil as methodology to identify change in soil dynamics. Results obtained show correlations among apparent electrical resistivity of the soil, moisture, soil compaction and clay content.

2

Currents' Physical Components (CPC) in Circuits with Nonsinusoidal Voltages and Currents. Part 2: Three-Phase Three-Wire Linear Circuits

Czarnecki L. S.

Electrical Power Quality and Utilisation. Journal

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2006

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Vol. 12, nr 1

3-13

EN

This paper summarizes the present state of discussions on power phenomena, power definitions and compensation in three-phase three-wire linear circuits with nonsinusoidal voltages and currents. In particular, definitions of the arithmetic and geometric apparent powers are discussed. It is shown that these two powers result in an erroneous value of power factor of unbalanced loads even if voltages and currents are sinusoidal. A reasoning that leads to a right selection of the apparent power definition is presented as well. The paper also presents the con-cept of the three-phase current decomposition into Currents' Physical Components (CPC) and its application for power definitions and compensation in three-phase circuits.

3

Currents' physical components (CPC) in circuits with nonsinusoidal voltages and currents. Part 1, Single-phase linear circuits

Czarnecki L. S.

Electrical Power Quality and Utilisation. Journal

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2005

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Vol. 11, nr 2

3-14

EN

The paper summarizes the present state of discussions on power phenomena, power definitions and compensation in single-phase linear circuits. The main concepts developed over several decades on how various non-active powers in circuits with nonsinusoidal voltages and currents should be defined and compensated are presented along with a detailed discussion of these concepts. The paper presents also the concept of the single-phase load current decomposition into Currents' Physical Components (CPC) and its application for power definitions and compensation in such circuits. The paper is not addressed to scientists and experts on powers, but rather to common electrical engineers that sometimes face power related problems in nonsinusoidal systems.