JPS54162149A - Neutral grounding monitor of generator - Google Patents

Neutral grounding monitor of generator

Info

Publication number
JPS54162149A
JPS54162149A JP7084078A JP7084078A JPS54162149A JP S54162149 A JPS54162149 A JP S54162149A JP 7084078 A JP7084078 A JP 7084078A JP 7084078 A JP7084078 A JP 7084078A JP S54162149 A JPS54162149 A JP S54162149A
Authority
JP
Japan
Prior art keywords
generator
zero
neutral point
impedance
phase
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP7084078A
Other languages
Japanese (ja)
Inventor
Minao Nagahama
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP7084078A priority Critical patent/JPS54162149A/en
Publication of JPS54162149A publication Critical patent/JPS54162149A/en
Pending legal-status Critical Current

Links

Landscapes

  • Emergency Protection Circuit Devices (AREA)
  • Protection Of Generators And Motors (AREA)

Abstract

PURPOSE: To discriminate either a grounding short of the generator neutral point or a cut of the neutral grounding device by detecting zero-phase voltage and zero- phase current, taking only a specific higher harmonic component from its output, and by computing the circuit impedance.
CONSTITUTION: The zero-phase voltage and zero-phase current of the generator 1 are detected by the auxiliary PT 10 and CT 7 respectively, and are fed to the third harmonic zero-phase impedance relay 11. The impedance relay takes only the third harmonic component by the third harmonic pass filter 111, 112, computes impedance of the circuit by the division unit 113, and decides whether the value is present within a fixed range, which is determined by both impedances of the generator and the neutral point grounding device, by the comparators 114, 115. Thus the fact that either a grounding short of the generator neutral point or a cut of the neutral point grounding device is present can be decided to prevent the occurrence of a serious accident.
COPYRIGHT: (C)1979,JPO&Japio
JP7084078A 1978-06-14 1978-06-14 Neutral grounding monitor of generator Pending JPS54162149A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP7084078A JPS54162149A (en) 1978-06-14 1978-06-14 Neutral grounding monitor of generator

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP7084078A JPS54162149A (en) 1978-06-14 1978-06-14 Neutral grounding monitor of generator

Publications (1)

Publication Number Publication Date
JPS54162149A true JPS54162149A (en) 1979-12-22

Family

ID=13443153

Family Applications (1)

Application Number Title Priority Date Filing Date
JP7084078A Pending JPS54162149A (en) 1978-06-14 1978-06-14 Neutral grounding monitor of generator

Country Status (1)

Country Link
JP (1) JPS54162149A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4507699A (en) * 1981-12-30 1985-03-26 Messer Griesheim Gmbh Protective device for the welding circuit of welding power sources
JPS61174603A (en) * 1985-01-29 1986-08-06 日新電機株式会社 Temperature monitor for midpoint ground resistor
JPS6445441U (en) * 1987-09-10 1989-03-20

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4507699A (en) * 1981-12-30 1985-03-26 Messer Griesheim Gmbh Protective device for the welding circuit of welding power sources
JPS61174603A (en) * 1985-01-29 1986-08-06 日新電機株式会社 Temperature monitor for midpoint ground resistor
JPS6445441U (en) * 1987-09-10 1989-03-20

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