Banca de DEFESA: ERICLES MAURICIO BARBOSA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ERICLES MAURICIO BARBOSA
DATE: 31/07/2023
TIME: 14:00
LOCAL: Presencial (DEE SL14) e por video: Link: https://meet.google.com/neh-denj-uri
TITLE:

EVALUATION OF THE USE OF 25 kHz CURRENTS IN THE  MEASUREMENT OF GROUNDING RESISTANCE OF  SUBSTATION GRIDS.

KEY WORDS:

Grounding; Grounding resistance; Grounding grid; Substation; Overhead ground wire; Electromagnetic coupling.

PAGES: 157
BIG AREA: Engenharias
AREA: Engenharia Elétrica
SUMMARY:

The connection of transmission lines overhead ground wires to the grounding  grids of substations represents a division path for the current injected by the measurement  equipment during grounding resistance measurements. The solution in these cases would be  to disconnect the wires to perform the measurement. However, this is not always possible,  leading to the need to adopt other strategies, such as using high-frequency earth meters.  These earth meters promote the decoupling of the ground wires due to the increased  impedance associated with high frequency. In this regard, the frequency of 25 kHz emerges  as a possible solution for use in substation measurements. However, there are still few  studies that evaluate the effects of this frequency in this application. Furthermore, there are  no regulatory standards that establish criteria for the use of high-frequency equipment in  these installations. This master thesis is inserted in this context, presenting an evaluation of  some of the effects that the use of high frequency can have on arrangements typically used  in substation grounding resistance measurements. A study was conducted to assess the  response of ground grids to currents of 100 Hz and 25 kHz in terms of their impedance, as  well as the occurrence of coupling between the voltage-current circuits and the current that flows through the ground wires. The simulations considered grids of varying dimensions and  soils with a wide range of resistivity. The analyses indicated that there are conditions in  which the results can present significant differences.

COMMITTEE MEMBERS:
Presidente - 2733127 - LAURO RODRIGO GOMES DA SILVA LOURENCO NOVO
Externo ao Programa - 2038043 - ALEXANDER BARROS LIMA - UFPEExterno à Instituição - CARLOS ERMÍDIO FERREIRA CAETANO - UFMG