• Title, Summary, Keyword: Off-line PD test

Search Result 13, Processing Time 0.047 seconds

Analysis and lest of On-line and off-line PD Testing for High Voltage Rotating Machines Stator Windings using Ceramic Coupler (세라믹 커플러를 이용한 고전압회전기 고정자권선의 On-line 및 off-line 부분방전 특성 시험 및 분석)

  • Oh, Bong-Keun;Kim, Hyun-Il;Kang, Seong-Hwa;Lim, Kee-Joe
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.20 no.10
    • /
    • pp.895-900
    • /
    • 2007
  • Partial discharge(PD) test can be performed either when the rotating machine is not operating(off-line) or during normal machine operation(on-line). This paper presents an on-line and off-line PD test on a large hydro-generator and induction motor using the same PD acquisition system(PDAS) and ceramic coupler(CC) sensor. PD signal characteristics of CC sensor proved similar with that of epoxy mica coupler(EMC) sensor as a results of PD test for simulated defect winding and frequency response test. A comparison of on-line and off-line PD test for PD characteristic parameters-phase resolved PD(PRPD), maximum PD value(Qmax) and PD occurrence energy(POE)-indicated that on-line PD test could reliably and effectively diagnose insulation conditions which were verified by off-line PD test.

A Case Study of On-line PD Measuring System on the Stator Winding for High Voltage Rotating Machine (고전압회전기 고정자권선 운전중 부분방전진단시스템의 현장적용사례 연구)

  • Oh, Bong-Keun;Kang, Dong-Sik;Lim, Kee-Joe
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.109-109
    • /
    • 2010
  • On-line partial discharge(PD) diagnostic system is the most prominent systems to diagnose insulation condition for the high voltage rotating machines. Partial discharge measuring system(PDMS) series with ceramic coupler(PD detecting sensor) installed hydro generator and high voltage motor have been measured the PD data for many years. The trend of PD magnitude in the on-line PD system increased for some machines. These machines showed a same result in the conventional off-line PD test and PD magnitude decreased after stator winding insulation cleaning. This case study show that PDMS has been proved to be good results by comparing PD magnitude with on-line and off-line PD test and it is important to plan the maintenance project for the hydro generator stator winding because PD value was decreased after insulation cleaning.

  • PDF

On-line and Off-line Partial Discharge Monitoring System with HVAC Testing (HVAC에 의한 On-line, Off-line PD 모니터링)

  • Choi, Yong-Sung;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.111-114
    • /
    • 2008
  • The paper considers the relation between on-line monitoring and diagnostics on the one hand and high-voltage (HV) withstand and partial discharge (PD) on-site testing on the other. HV testing supplies the basic data (fingerprints) for diagnostics. In case of warnings by on-line diagnostic systems, off-line withstand and PD testing delivers the best possible information about defects and enables the classification of the risk. Because alternating voltage (AC) is the most important test voltage, the AC generation on site is considered. Frequency tuned resonant (ACRF) test systems are best adapted to on-site conditions. They can be simply combined with PD measuring equipment. The available ACRF test systems and their application to electric power equipment -from cable systems to power transformers - is described.

  • PDF

Site Evaluation and Application of the On-line and Off-line Test for the 13[kV] Class Hydropower Generator Stator Windings (13[kV]급 수력발전기 고정자 권선의 운전 및 정지 중 진단시험 현장적용 평가 및 분석)

  • Chang, Jeong-Ho;Lee, Dong-Keun;Lee, Heung-Ho
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.25 no.11
    • /
    • pp.73-82
    • /
    • 2011
  • The solid insulation system of stator windings in high voltage rotational machines is usually aging in accordance with long time operation. The partial discharge test have been known to check whether insulation deterioration exist or not, and the PD test can effectively diagnose a solid insulation condition regardless of during operation(on-line) or not(off-line). The on-line PD measurement have proven to be a successful technique in monitoring stator insulation condition nowadays. This paper describes the characteristics of comparing the on-line PD measurement data using PDMS-HG(Partial Discharge Monitoring System for Hydro-electric Generator) installed in field with the off-line diagnosis measurement data(insulation resistance, winding resistance, PI, ${\Delta}tan{\delta}$ and PD) on hydro generator(13[kV]) stator windings. These results make good use of managing rotational machines through evaluating the solid insulation condition of stator windings.

A Research Trend on On-Line/Off-Line PD Insulation Diagnostic System (온라인 및 오프라인 PD 모니터링에 관한 연구 동향)

  • Choo, Jong-Hoon;Hong, Chang-Il;Choi, Yong-Sung;Lee, Kyung-Sup
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.2008-2009
    • /
    • 2007
  • The paper considers the relation between on-line monitoring and diagnostics on the one hand and high-voltage (HV) withstand and partial discharge (PD) on-site testing on the other. HV testing supplies the basic data (fingerprints) for diagnostics. In case of warnings by on-line diagnostic systems, off-line withstand and PD testing delivers the best possible information about defects and enables the classification of the risk. Because alternating voltage (AC) is the most important test voltage, the AC generation on site is considered. Frequency tuned resonant (ACRF) test systems are best adapted to on-site conditions. They can be simply combined with PD measuring equipment. The available ACRF test systems and their application to electric power equipment -from cable systems to power transformers - is introduced.

  • PDF

Trend in Off-Line PD Monitoring with HVAC Testing (배전반 설비의 온라인 모니터링 및 진단의 동향)

  • Yun, Ju-Ho;Hong, Chang-Il;Hwang, Jong-Sun;Choi, Yong-Sung;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • /
    • pp.529-530
    • /
    • 2007
  • The paper considers the relation between on-line monitoring and diagnostics on the one hand and high-voltage (HV) withstand and partial discharge (PD) on-site testing on the other. HV testing supplies the basic data (fingerprints) for diagnostics. In case of warnings by on-line diagnostic systems, off-line withstand and PD testing delivers the best possible information about defects and enables the classification of the risk. Because alternating voltage (AC) is the most important test voltage, the AC generation on site is considered. Frequency tuned resonant (ACRF) test systems are best adapted to on-site conditions. They can be simply combined with PD measuring equipment. The available ACRF test systems and their application to electric power equipment -from cable systems to power transformers - is described.

  • PDF

Insulation Aging Properties of Off-Line and On-Line High Voltage Motor Stator (정지중 및 운전중 고압전동기 고정자 권선의 절연열화 특성)

  • Kim, Hee-Dong;Lee, Young-Jun;Ju, Young-Ho
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.1694-1696
    • /
    • 2001
  • Partial discharge(PD) tests are used to evaluate the insulation condition of stator windings in six 6.6kV motors. These tests were conducted using a conventional partial discharge detector (PDD), turbine generator analyzer(TGA) and partial discharge analyzer(PDA). Off-line PD measurements were performed on six 6.6kV motors. PD magnitudes ranged from 740 pC to 5,100 pC at the normal line-to-ground voltage. Six 6.6kV motors have been equipped with eighteen 80pF epoxy-mica couplers(one per phase) on the motor terminal boxs. The PD pulse from sensors were measured with the TGA and PDA instruments on a normally operating motors. The PDD, TGA and PDA test results showed that internal discharge was detected in voids of the groundwall insulation.

  • PDF

On-Line System for Partial Monitoring Discharge (온라인 부분방전 감시 시스템)

  • Choi, Yong-Sung;Hwang, Jong-Sun;Lee, Kyung-Sup
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.2114-2115
    • /
    • 2008
  • We consider the relation between on-line monitoring and diagnostics on the one hand and high-voltage (HV) withstand and partial discharge (PD) on-site testing on the other. HV testing supplies the basic data (fingerprints) for diagnostics. In case of warnings by on-line diagnostic systems, off-line withstand and PD testing delivers the best possible information about defects and enables the classification of the risk. Frequency tuned resonant (ACRF) test systems are best adapted to on-site conditions. They can be simply combined with PD measuring equipment. The available ACRF test systems and their application to electric power equipment -from cable systems to power transformers is described.

  • PDF

Partial Discharge Measurements of High Voltage Rotating Machine Stator Windings (고압회전기 고정자 권선의 부분방전 측정)

  • Kim, Hee-Dong;Lee, Young-Jun;Kong, Tae-Sik
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.1828-1830
    • /
    • 2003
  • Partial discharge(PD) tests are used to evaluate the insulation condition of stator windings in two 4.16kV and three 6.6kV motors. These tests were conducted using a conventional partial discharge detector(PDD) and turbine generator analyzer(TGA). Off-line PD measurements were performed on five high voltage motors. PD magnitudes ranged from 1000 pC to 5400 pC at the normal line-to-ground voltage. Five high voltage motors have been equipped with 80pF epoxy-mica coupler on the motor terminal box. The PD pulse from sensors were measured with the TGA instrument. TGA summarizes each plot with two Quantities such as the peak PD magnitude(Qm) and the total PD activity(NQN). The defect mechanisms of high voltage motor can be associated with PD patterns such as internal, slot and conductor surface discharges. The PDD and TGA test results of No. 4 motor showed that internal discharge was detected in voids of the groundwall insulation.

  • PDF

Reliability Assessment of High Voltage Rotating Machine Stator Windings Through Off-line Diagnosis (고압회전기기 고정자권선의 Off-line 진단을 통한 신뢰성 평가)

  • Chang, Jeong-Ho;Lim, Jae-Il;Lee, Dong-Keun;Lee, Heung-Ho
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.1628-1629
    • /
    • 2011
  • 산업현장에서는 회전기기의 고체절연시스템(solid insulation system)의 열화정도를 평가하기 위하여 일정 진단주기에 맞춰 Off-line 상태에서 직류시험 및 교류시험을 통하여 효과적으로 절연물에 대한 상태평가를 시행하고 있다. 직류시험으로는 절연저항, 성극지수(PI) 시험 등이 있으며 교류시험으로는 교류전류시험(${\Delta}I$), 유전정접시험(${\Delta}tan{\delta}$), 부분방전(PD)시험이 있다. 여기서 부분방전은 절연체의 국부적인 열화현상을 추정할 수 있는 중요한 파라미터로, 부분방전시험(PD test)을 통하여 고정자권선(stator winding)에 대한 절연특성을 효과적으로 진단할 수 있다. 고압 전동기는 기동정지의 빈번함과 장기간 운전에 의해 열적, 전기적, 기계적 스트레스를 받게 되고, 이로 인해 과열, 진동, 절연파괴에 이르는 문제점이 발생되어 결국 시스템의 운전정지를 초래하는 심각한 사고로 이어질 수 있다. 따라서 고압 전동기의 절연상태를 주기적으로 감시하고 사고 징후를 검출하여 시스템을 안정적으로 운영하기 위한 고압 전동기 Off-line 절연진단에 대하여 기술하고 수차발전기에 대한 절연상태진단 결과를 바탕으로 절연시스템의 신뢰성 평가 방법에 대하여 고찰하고자 한다.

  • PDF