IEC 60076-18:2012 covers the measurement technique and measuring equipment to be used when a frequency response measurement is required either on-site or in the factory either when the test object is new or at a later stage. This standard is applicable to power transformers, reactors, phase shifting transformers and similar equipment.<\/p>\n
| PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
|---|---|---|---|---|---|---|---|
| 5<\/td>\n | English CONTENTS <\/td>\n<\/tr>\n | ||||||
| 8<\/td>\n | 1 Scope 2 Terms and definitions <\/td>\n<\/tr>\n | ||||||
| 9<\/td>\n | 3 Purpose of frequency response measurements <\/td>\n<\/tr>\n | ||||||
| 10<\/td>\n | 4 Measurement method 4.1 General <\/td>\n<\/tr>\n | ||||||
| 12<\/td>\n | 4.3 Measurement connection and checks 4.3.1 Measurement connection and earthing 4.3.2 Zero-check measurement 4.3.3 Repeatability check 4.3.4 Instrument performance check <\/td>\n<\/tr>\n | ||||||
| 13<\/td>\n | 4.4 Measurement configuration 4.4.1 General 4.4.2 Principles for choosing the measurement configuration <\/td>\n<\/tr>\n | ||||||
| 14<\/td>\n | 4.4.3 Star- and auto-connected windings with a neutral terminal 4.4.4 Delta windings and other windings without an accessible neutral Tables Table 1 \u2013 Standard measurements for a star connected winding with taps <\/td>\n<\/tr>\n | ||||||
| 15<\/td>\n | 4.4.5 Zig-zag connected windings 4.4.6 Two-winding three-phase transformers 4.4.7 Three-phase auto-transformers 4.4.8 Phase shifting transformers 4.4.9 Reactors 4.4.10 Method for specifying additional measurements Table 2 \u2013 Standard measurements for delta connected winding without tap <\/td>\n<\/tr>\n | ||||||
| 16<\/td>\n | 4.5 Frequency range and measurement points for the measurement 5 Measuring equipment 5.1 Measuring instrument 5.1.1 Dynamic range Table 3 \u2013 Format for specifying additional measurements <\/td>\n<\/tr>\n | ||||||
| 17<\/td>\n | 5.1.2 Amplitude measurement accuracy 5.1.3 Phase measurement accuracy 5.1.4 Frequency range 5.1.5 Frequency accuracy 5.1.6 Measurement resolution bandwidth 5.1.7 Operating temperature range 5.1.8 Smoothing of recorded data 5.1.9 Calibration 5.2 Measurement leads <\/td>\n<\/tr>\n | ||||||
| 18<\/td>\n | 5.3 Impedance 6 Measurement records 6.1 Data to be recorded for each measurement <\/td>\n<\/tr>\n | ||||||
| 19<\/td>\n | 6.2 Additional information to be recorded for each set of measurements <\/td>\n<\/tr>\n | ||||||
| 21<\/td>\n | Annex A (normative) Measurement lead connections <\/td>\n<\/tr>\n | ||||||
| 22<\/td>\n | Figure A.1 \u2013 Method 1 connection <\/td>\n<\/tr>\n | ||||||
| 23<\/td>\n | Figure A.2 \u2013 Method 3 connection <\/td>\n<\/tr>\n | ||||||
| 24<\/td>\n | Annex B (informative) Frequency response and factors that influence the measurement Figure B.1 \u2013 Presentation of frequency response measurements <\/td>\n<\/tr>\n | ||||||
| 25<\/td>\n | Figure B.2 \u2013 Comparison with a baseline measurement Figure B.3 \u2013 Comparison of the frequency responses of twin transformers <\/td>\n<\/tr>\n | ||||||
| 26<\/td>\n | Figure B.4 \u2013 Comparison of the frequency responses from sister transformers Figure B.5 \u2013 Comparison of the frequency responses of three phases of a winding <\/td>\n<\/tr>\n | ||||||
| 28<\/td>\n | Figure B.6 \u2013 General relationships between frequency response and transformer structure and measurement set-up for HV windings of large auto-transformer <\/td>\n<\/tr>\n | ||||||
| 29<\/td>\n | Figure B.7 \u2013 Effect of tertiary delta connection on the frequency response of a series winding <\/td>\n<\/tr>\n | ||||||
| 30<\/td>\n | Figure B.8 \u2013 Effect of star neutral connection on the tertiary winding response Figure B.9 \u2013 Effect of star neutral termination on series winding response <\/td>\n<\/tr>\n | ||||||
| 31<\/td>\n | Figure B.10 \u2013 Measurement results showing the effect of differences between phases in internal leads connecting the tap winding and OLTC Figure B.11 \u2013 Effect of measurement direction on frequency response <\/td>\n<\/tr>\n | ||||||
| 32<\/td>\n | Figure B.12 \u2013 Effect of different types of insulating fluid on frequency response Figure B.13 \u2013 Effect of oil filling on frequency response <\/td>\n<\/tr>\n | ||||||
| 33<\/td>\n | Figure B.14 \u2013 Effect of a DC injection test on the frequency response Figure B.15 \u2013 Effect of bushings on frequency response <\/td>\n<\/tr>\n | ||||||
| 34<\/td>\n | Figure B.16 \u2013 Effect of temperature on frequency response <\/td>\n<\/tr>\n | ||||||
| 35<\/td>\n | Figure B.17 \u2013 Examples of bad measurement practice Figure B.18 \u2013 Frequency response of a tap winding before and after partial axial collapse and localised inter-turn short-circuit with a photograph of the damage <\/td>\n<\/tr>\n | ||||||
| 36<\/td>\n | Figure B.19 \u2013 Frequency response of an LV winding before and after axial collapse due to clamping failure with a photograph of the damage [8] <\/td>\n<\/tr>\n | ||||||
| 37<\/td>\n | Figure B.20 \u2013 Frequency response of a tap winding with conductor tiltingwith a photograph of the damage [1] <\/td>\n<\/tr>\n | ||||||
| 38<\/td>\n | Annex C (informative) Applications of frequency response measurements <\/td>\n<\/tr>\n | ||||||
| 40<\/td>\n | Annex D (informative) Examples of measurement configurations Table D.1 \u2013 Standard end-to-end measurements on a three-phase auto-transformer <\/td>\n<\/tr>\n | ||||||
| 41<\/td>\n | Figure D.1 \u2013 Winding diagram of an auto-transformer with a line-end tap changer Table D.2 \u2013 Tap-changer connections <\/td>\n<\/tr>\n | ||||||
| 42<\/td>\n | Figure D.2 \u2013 Connection diagram of an inductive inter-winding measurement on a three-phase YNd1 transformer Table D.3 \u2013 Inductive inter-winding measurements on a three-phase YNd1 transformer Table D.4 \u2013 Capacitive inter-winding measurements on a three-phase YNd1 transformer <\/td>\n<\/tr>\n | ||||||
| 43<\/td>\n | Figure D.3 \u2013 Connection diagram for a capacitive inter-winding measurement on a three-phase YNd1 transformer Figure D.4 \u2013 Connection diagram for an end-to-end short-circuit measurement on a three-phase YNd1 transformer Table D.5 \u2013 End-to-end short-circuit measurements on a three-phase YNd1 transformer <\/td>\n<\/tr>\n | ||||||
| 44<\/td>\n | Annex E (informative) XML data format <\/td>\n<\/tr>\n | ||||||
| 45<\/td>\n | Bibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Power transformers – Measurement of frequency response<\/b><\/p>\n |