{"id":385535,"date":"2024-10-20T03:31:09","date_gmt":"2024-10-20T03:31:09","guid":{"rendered":"https:\/\/pdfstandards.shop\/product\/uncategorized\/bsi-pd-iec-ts-63042-2022021\/"},"modified":"2024-10-26T06:23:30","modified_gmt":"2024-10-26T06:23:30","slug":"bsi-pd-iec-ts-63042-2022021","status":"publish","type":"product","link":"https:\/\/pdfstandards.shop\/product\/publishers\/bsi\/bsi-pd-iec-ts-63042-2022021\/","title":{"rendered":"BSI PD IEC TS 63042-202:2021"},"content":{"rendered":"

This part of IEC 63042 provides common rules for the design of overhead transmission lines with the highest voltages of AC transmission systems exceeding 800 kV, so as to provide safety and proper functioning for the intended use.<\/p>\n

This technical specification aims to give the main principles for the design of UHV AC overhead transmission lines, mainly including selection of clearance, insulation coordination and insulator strings design, bundle-conductor selection, earth wire\/optical ground wires selection, tower and foundation design, environmental consideration. The design criteria apply to new construction, reconstruction and expansion of UHV AC overhead transmission line.<\/p>\n

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PDF Pages<\/th>\nPDF Title<\/th>\n<\/tr>\n
2<\/td>\nundefined <\/td>\n<\/tr>\n
4<\/td>\nCONTENTS <\/td>\n<\/tr>\n
12<\/td>\nFOREWORD <\/td>\n<\/tr>\n
14<\/td>\n1 Scope
2 Normative references <\/td>\n<\/tr>\n
15<\/td>\n3 Terms and definitions
4 Symbols and abbreviations <\/td>\n<\/tr>\n
16<\/td>\n5 UHV AC transmission line requirements
5.1 General requirements
5.2 Reliability requirements
5.3 Electrical requirements
5.4 Security requirements
5.5 Safety requirements
5.6 Environmental impact
5.7 Economy <\/td>\n<\/tr>\n
17<\/td>\n6 Selection of clearance
6.1 General
6.2 Air gap, tower clearances (strike distance)
6.2.1 Power frequency voltage
6.2.2 Switching overvoltage
6.2.3 Lightning overvoltage <\/td>\n<\/tr>\n
18<\/td>\n6.3 Phase to phase spacing (Horizontal, Vertical)
6.4 Ground clearances \u2013 Statutory requirements, electric and magnetic field limits
6.5 Conductor-earth wire spacing, shielding angle \u2013 Lightning performance criteria <\/td>\n<\/tr>\n
19<\/td>\n7 Insulation coordination, insulator and insulator string design
7.1 General
7.2 Insulation requirements \u2013 electrical design considerations
7.3 Insulating materials, type of insulators <\/td>\n<\/tr>\n
20<\/td>\n7.4 Insulator string configurations for disc type insulators <\/td>\n<\/tr>\n
21<\/td>\n7.5 Mechanical design criteria of insulator strings and associated hardware fittings
8 Bundle-conductor selection
8.1 General
8.2 Conductor types <\/td>\n<\/tr>\n
22<\/td>\n8.3 Bundle conductor configurations
8.3.1 Number of sub-conductors
8.3.2 Bundle spacing
8.4 Conductor bundle selection process
8.4.1 Cross-section of conductor
8.4.2 Conductor ampacity <\/td>\n<\/tr>\n
23<\/td>\n8.4.3 Requirements for electromagnetic environment
8.4.4 Capital cost and loss evaluation
8.5 Mechanical strength <\/td>\n<\/tr>\n
24<\/td>\n8.6 Conductor accessories
8.6.1 General requirements for fittings
8.6.2 Type and design features of link fittings, vibration dampers, spacers <\/td>\n<\/tr>\n
25<\/td>\n9 Earth wire\/OPGW selection
9.1 General
9.2 Type of earth wire\/OPGW
9.3 Design Criteria\/Requirements Specific to UHV Lines
9.4 Induced voltages on earth wire <\/td>\n<\/tr>\n
26<\/td>\n10 Tower and foundation design
10.1 General
10.2 Tower classification
10.2.1 General
10.2.2 Conductor configuration <\/td>\n<\/tr>\n
27<\/td>\nFigures
Figure 1 \u2013 Typical single circuit vertical configuration tower
Figure 2 \u2013 Typical double circuit vertical configuration tower <\/td>\n<\/tr>\n
28<\/td>\nFigure 3 \u2013 Typical single circuit horizontal configuration tower
Figure 4 \u2013 Typical single circuit delta configuration tower <\/td>\n<\/tr>\n
29<\/td>\nFigure 5 \u2013 Typical single circuit H-type tower
Figure 6 \u2013 Typical double circuit danube configuration tower <\/td>\n<\/tr>\n
30<\/td>\nFigure 7 \u2013 1 200 kV single circuit vertical configuration tower
Figure 8 \u2013 1 200 kV single circuit horizontal configuration tower
Figure 9 \u2013 1 200 kV double circuit vertical Configuration tower <\/td>\n<\/tr>\n
31<\/td>\n10.2.3 Constructional features
10.2.4 Line deviation angle
Figure 10 \u2013 1 200 kV single circuit H-type tower (for gantry) <\/td>\n<\/tr>\n
32<\/td>\n10.2.5 Tower extensions
10.2.6 Specific requirements
10.3 Tower design
10.3.1 General
10.3.2 Selection of tower geometry based on electrical clearances <\/td>\n<\/tr>\n
33<\/td>\n10.3.3 Calculation of loads on tower
10.3.4 Analysis using software <\/td>\n<\/tr>\n
34<\/td>\n10.3.5 Full scale tower testing
10.3.6 Tower design methodology <\/td>\n<\/tr>\n
35<\/td>\n10.4 Foundation design
10.4.1 General
Figure 11 \u2013 Tower design methodology <\/td>\n<\/tr>\n
36<\/td>\n10.4.2 Open cast type foundations
10.4.3 Raft type foundations <\/td>\n<\/tr>\n
37<\/td>\n10.4.4 Deep foundations (Pile\/Well\/Pier\/Steel Anchor type)
11 Environmental considerations
11.1 General
11.2 Electric field
11.2.1 General
11.2.2 Reference level of electric field <\/td>\n<\/tr>\n
38<\/td>\n11.2.3 Prediction of electric field
11.2.4 Mitigation measures of electric field
11.3 Magnetic field
11.3.1 General
11.3.2 Reference level of magnetic field
11.3.3 Prediction of magnetic field <\/td>\n<\/tr>\n
39<\/td>\n11.3.4 Mitigation measures of magnetic field
11.4 Corona noise (audible noise with corona discharge)
11.4.1 General
11.4.2 Characteristics of corona noise
11.4.3 Reference level of corona noise <\/td>\n<\/tr>\n
40<\/td>\n11.4.4 Prediction of corona noise
11.4.5 Mitigation measures of corona noise
11.5 Radio interference with corona discharge
11.5.1 General
11.5.2 Characteristics of radio interference <\/td>\n<\/tr>\n
41<\/td>\n11.5.3 Reference level of radio interference
11.5.4 Prediction of radio interference
11.5.5 Mitigation measures of radio interference
11.6 Wind noise <\/td>\n<\/tr>\n
42<\/td>\nAnnex A (informative)Experimental results and considerations on environmental performance of UHV AC transmission lines in different countries
A.1 General
A.2 Experimental results and considerations on environmental performance of UHV AC transmission lines in China
A.2.1 Radio interference
A.2.2 Audible noise
Tables
Table A.1 \u2013 Design limits for radio interference in China
Table A.2 \u2013 Criteria for environmental noises in the five categoriesof areas in cities (dB (A)) <\/td>\n<\/tr>\n
43<\/td>\nA.2.3 Electric field
A.3 Experimental results and considerations on environmental performance of UHV AC transmission lines in India
A.3.1 Electrical Clearances from buildings, structures, etc.
A.3.2 Electric field
A.3.3 Radio interference
A.3.4 Audible noise <\/td>\n<\/tr>\n
44<\/td>\nA.4 Experimental results and considerations on environmental performance of UHV AC transmission lines in Japan
A.4.1 General
A.4.2 AN (audible noise) <\/td>\n<\/tr>\n
45<\/td>\nA.4.3 RI (Radio Interference)
A.4.4 EMF (Electromagnetic field) <\/td>\n<\/tr>\n
46<\/td>\nFigure A.1 \u2013 Results of sensing tests under transmission lines
Table A.3 \u2013 Reference level of electric field and ground height of conductor <\/td>\n<\/tr>\n
47<\/td>\nA.4.5 Electromagnetic induction interference, Electrostatic induction interference
A.4.6 Wind noise from conductor <\/td>\n<\/tr>\n
48<\/td>\nA.4.7 Ice and snow falling from conductor
Figure A.2 \u2013 Symbols related to wind noise prediction formula <\/td>\n<\/tr>\n
49<\/td>\nA.4.8 Landscape impact <\/td>\n<\/tr>\n
50<\/td>\nA.4.9 Nature conservation <\/td>\n<\/tr>\n
52<\/td>\nAnnex B (informative)Design practice of UHV AC transmission lines in different countries
B.1 General
B.2 Design practice in China
B.2.1 General
B.2.2 Conductor and earth wire
Table B.1 \u2013 Conductor type selection <\/td>\n<\/tr>\n
53<\/td>\nTable B.2 \u2013 Conductor characteristics <\/td>\n<\/tr>\n
54<\/td>\nB.2.3 Electrical clearances
Table B.3 \u2013 Coefficient ki <\/td>\n<\/tr>\n
55<\/td>\nB.2.4 Insulation coordination
Figure B.1 \u2013 Composite insulator profiles <\/td>\n<\/tr>\n
56<\/td>\nTable B.4 \u2013 Recommended configuration of tension insulatorstring in light and medium ice zone
Table B.5 \u2013 Recommended configuration of tension insulatorstring in substation outlet span <\/td>\n<\/tr>\n
57<\/td>\nFigure B.2 \u2013 1 200 kV insulator profile
Table B.6 \u2013 Recommended value of single circuit line air gap
Table B.7 \u2013 Recommended value of double circuit line air gap <\/td>\n<\/tr>\n
58<\/td>\nB.2.5 Tower and foundation <\/td>\n<\/tr>\n
60<\/td>\nB.3 Design practice in India
B.3.1 General
B.3.2 Challenges in development and solutions
B.3.3 Conductor selection <\/td>\n<\/tr>\n
61<\/td>\nTable B.8 \u2013 Conductor capacity
Table B.9 \u2013 Conductor surface gradient
Table B.10 \u2013 Conductor radio interference
Table B.11 \u2013 Conductor audible noise <\/td>\n<\/tr>\n
62<\/td>\nB.3.4 Electrical clearances
Figure B.3 \u2013 1 200 kV air-gap experimental tests
Table B.12 \u2013 Conductor electric field <\/td>\n<\/tr>\n
63<\/td>\nB.3.5 Insulation requirements
Table B.13 \u2013 Salient results of the experimental tests <\/td>\n<\/tr>\n
64<\/td>\nB.3.6 1 200 kV test line
Figure B.4 \u2013 1 200 kV single circuit test line <\/td>\n<\/tr>\n
65<\/td>\nB.3.7 400 kV double circuit (upgradable to 1 200 kV single circuit) line
Figure B.5 \u2013 1 200 kV double circuit test line
Table B.14 \u2013 Salient features of the 1 200 kV test lines <\/td>\n<\/tr>\n
66<\/td>\nFigure B.6 \u2013 1 200 kV upgradable line \u2013Suspension tower
Figure B.7 \u2013 1 200 kV upgradable line \u2013Tension tower <\/td>\n<\/tr>\n
67<\/td>\nB.4 Design practice in Japan
B.4.1 General
Figure B.8 \u2013 1 200 kV Tower Prototype Testing
Table B.15 \u2013 Salient features of 1 200 kV upgraded transmission line <\/td>\n<\/tr>\n
68<\/td>\nB.4.2 Conductor and earth wire
Figure B.9 \u2013 UHV AC transmission lines in Japan
Table B.16 \u2013 UHV AC transmission lines in Japan
Table B.17 \u2013 Conductor configuration and AN <\/td>\n<\/tr>\n
69<\/td>\nB.4.3 Insulation coordination
Figure B.10 \u2013 Shape of conductor
Figure B.11 \u2013 Shape of OPGW <\/td>\n<\/tr>\n
70<\/td>\nTable B.18 \u2013 Specifications of insulator
Table B.19 \u2013 Withstand voltage of single insulator in pollution [kV\/unit]
Table B.20 \u2013 Withstand voltage of single insulator under snow [kV\/unit] <\/td>\n<\/tr>\n
71<\/td>\nTable B.21 \u2013 Altitude correction factor K1 <\/td>\n<\/tr>\n
72<\/td>\nB.4.4 Wind noise <\/td>\n<\/tr>\n
73<\/td>\nB.4.5 Tower and foundation <\/td>\n<\/tr>\n
74<\/td>\nTable B.22 \u2013 Loads for tower design <\/td>\n<\/tr>\n
75<\/td>\nFigure B.12 \u2013 Foundation type <\/td>\n<\/tr>\n
76<\/td>\nAnnex C (informative)Construction practice of UHV AC transmission lines in different countries
C.1 General
C.2 Construction practice in China
Figure C.1 \u2013 Machinery for foundation construction <\/td>\n<\/tr>\n
77<\/td>\nC.3 Construction practice in India
C.4 Construction practice in Japan <\/td>\n<\/tr>\n
79<\/td>\nAnnex D (informative)Flashover voltage test result for air clearances in different countries
D.1 General
D.2 Flashover voltage test result for air clearances in China
D.2.1 50 % Power frequency flashover voltage test results for air clearances of transmission line structures
Figure D.1 \u2013 The arrangement of power frequency flashover voltage testfor side-phase air clearances of 1 000 kV cat-head type towers
Figure D.2 \u2013 The 50 % power frequency flashover voltage characteristic for air clearance from side-phase conductor to tower body for 1 000 kV cat-head type towers <\/td>\n<\/tr>\n
80<\/td>\nFigure D.3 \u2013 The arrangement of power frequency flashover voltage testfor side-phase air clearances of 1 000 kV cup type towers
Figure D.4 \u2013 The 50 % power frequency flashover voltage characteristicfor air clearance from side-phase conductor to tower body for 1 000 kV cuptype towers 1 000 kV cup type towers <\/td>\n<\/tr>\n
81<\/td>\nFigure D.5 \u2013 The arrangement of power frequency flashover voltage testfor air clearances of 1 000 kV double-circuit lines
Figure D.6 \u2013 The 50 % power frequency flashover voltage characteristicfor air clearance from middle-phase conductor with I-type stringto tower body for 1 000 kV double-circuit lines <\/td>\n<\/tr>\n
82<\/td>\nD.2.2 50 % Switching impulse flashover voltage test results for air clearances of transmission line structures
Figure D.7 \u2013 The arrangement of the power frequency flashover voltage test for air clearances of bottom-phase with I-type string of 1 000 kV double-circuit lines
Figure D.8 \u2013 The power frequency flashover voltage characteristicof air clearance from bottom-phase conductor (with I-type string)to tower body of 1 000 kV double-circuit lines <\/td>\n<\/tr>\n
83<\/td>\nFigure D.9 \u2013 The arrangement of switching impulse flashover voltage testfor side-phase air clearances of 1 000 kV cat-head type towers
Figure D.10 \u2013 The 50 % switching impulse flashover voltage characteristicfor air clearances from conductor to tower body of 1 000 kV lines(with a time to peak of 250 \u00b5s)
Table D.1 \u2013 Switching impulse flashover voltages of side-phase air clearancesof 1 000 kV cat-head type towers with different test time to peak <\/td>\n<\/tr>\n
84<\/td>\nFigure D.11 \u2013 The arrangement of switching impulse flashover voltage testfor middle-phase air clearances of 1 000 kV cat-head type towers
Figure D.12 \u2013 The arrangement of switching impulse flashover voltage test for side-phase air clearances of 1 000 kV cup type towers
Table D.2 \u2013 The switching impulse flashover voltage of air clearancesfrom middle-phase conductor to tower for 1 000 kV full-scale towers <\/td>\n<\/tr>\n
85<\/td>\nFigure D.13 \u2013 The 50 % switching impulse flashover voltage characteristicfor air clearances from conductor to tower body of 1 000 kV lines(with a time to peak of 250 \u00b5s)
Figure D.14 \u2013 The arrangement of switching impulse flashover voltage test for middle-phase air clearances of 1 000 kV cup type towers
Table D.3 \u2013 The switching impulse flashover voltage for air clearancefrom the middle-phase conductor to tower window in the arrangementshown in Figure D.14 a) and Figure D.14 b) <\/td>\n<\/tr>\n
86<\/td>\nFigure D.15 \u2013 The arrangement of switching impulse flashover voltagetest at long time to peak for middle-phase air clearances (with I-type string)of 1 000 kV double-circuit lines
Figure D.16 \u2013 The 50 % switching impulse (1 000 \u03bcs) flashover voltage characteristicfor air clearances from conductor to bottom crossarm of 1 000 kV double-circuit lines(a distance of 9,0 m between conductor and middle crossarm) <\/td>\n<\/tr>\n
87<\/td>\nFigure D.17 \u2013 The arrangement of switching impulse flashover voltage testfor air clearances from middle-phase conductor (with V-type string)to bottom crossarm of 1 000 kV double-circuit lines
Figure D.18 \u2013 The 50 % switching impulse (1 000 \u03bcs) flashover voltage characteristic of air clearances from conductor to bottom crossarm of 1 000 kV double-circuit lines <\/td>\n<\/tr>\n
88<\/td>\nFigure D.19 \u2013 The arrangement of switching impulse flashover testfor air clearances from middle-phase conductor (with V-type string)to tower body of 1 000 kV double-circuit lines
Figure D.20 \u2013 The 50 % switching impulse (1 000 \u03bcs) flashover voltage characteristic for air clearances from conductor to tower body of 1 000 kV double-circuit lines <\/td>\n<\/tr>\n
89<\/td>\nFigure D.21 \u2013 The arrangement of switching impulse flashover voltage testfor air clearances from middle-phase conductor (with V-type string)to middle crossarm of 1 000 kV double-circuit lines
Figure D.22 \u2013 The 50 % switching impulse (1 000 \u03bcs) flashover voltage characteristic for air clearances from conductor to middle crossarm of 1 000 kV double-circuit lines <\/td>\n<\/tr>\n
90<\/td>\nFigure D.23 \u2013 The arrangement of switching impulse flashover voltage testfor air clearances from bottom-phase conductor (with V-type string)to crossarm of 1 000 kV double-circuit lines
Figure D.24 \u2013 The 50 % switching impulse (1 000 \u03bcs) flashover voltage characteristic for air clearances from conductor to crossarm of 1 000 kV double-circuit lines <\/td>\n<\/tr>\n
91<\/td>\nD.2.3 50 % Lightning impulse flashover voltage test results for air clearances of transmission line structures
Figure D.25 \u2013 The arrangement of switching impulse flashover voltage testfor air clearances from bottom-phase conductor (with V-type string)to tower body of 1 000 kV double-circuit lines
Figure D.26 \u2013 The 50 % switching impulse (1 000 \u03bcs) flashover voltage characteristic for air clearances from conductor to tower body of 1 000 kV double-circuit lines <\/td>\n<\/tr>\n
92<\/td>\nFigure D.27 \u2013 The 50 % lightning impulse flashover voltage characteristic for air clearances from side-phase conductor to tower body of 1 000 kV single-circuit lines
Figure D.28 \u2013 The arrangement of lightning impulse flashover voltage testfor air clearances from middle-phase conductor (with I-type string)to bottom crossarm of 1 000 kV double-circuit lines <\/td>\n<\/tr>\n
93<\/td>\nFigure D.29 \u2013 The 50 % lightning impulse flashover voltage characteristic for air clearances from conductor to lower crossarm of 1 000 kV double-circuit lines
Figure D.30 \u2013 The arrangement of lightning impulse flashover voltage testfor air clearances from middle-phase conductor (with V-type string)to bottom crossarm of 1 000 kV double-circuit lines <\/td>\n<\/tr>\n
94<\/td>\nD.2.4 Effects of switching overvoltage time to peak on flashover voltage
Figure D.31 \u2013 The 50 % positive and negative lightning impulseflashover voltage characteristic for air clearances from conductorto lower crossarm of 1 000 kV double-circuit lines
Figure D.32 \u2013 Curve of the 50 % switching impulse flashover voltage as a function of the time to peak for the air clearance from conductor to tower leg of 5 m <\/td>\n<\/tr>\n
95<\/td>\nD.2.5 Tower width correction approaches for air clearances of transmission line structures <\/td>\n<\/tr>\n
96<\/td>\nFigure D.33 \u2013 Tower-width voltage correction factor
Figure D.34 \u2013 Tower-width spacing correction factor <\/td>\n<\/tr>\n
97<\/td>\nD.4 Flashover voltage test result for air clearances in Japan
D.4.1 50 % Power frequency flashover voltage test results of transmission line\u3000structures
D.3 Flashover voltage test result for air clearances in India
Figure D.35 \u2013 Effects of tower leg width on switching impulse flashover voltage(with a time to peak of 720 \u03bcs) <\/td>\n<\/tr>\n
98<\/td>\nD.4.2 50 % Switching impulse flashover voltage test results for air clearances of transmission line structures
Figure D.36 \u2013 The 50 % power frequency flashover voltage characteristicfor air clearance for 1 000 kV
Table D.4 \u2013 Altitude correction factor K1
Table D.5 \u2013 Gap coefficient k <\/td>\n<\/tr>\n
99<\/td>\nFigure D.37 \u2013 The arrangement of switching impulse flashover voltage testfor air clearances of 1 000 kV tension type towers
Table D.6 \u2013 Altitude correction factor K1 <\/td>\n<\/tr>\n
100<\/td>\nFigure D.38 \u2013 The 50 % switching impulse flashover voltage characteristicfor air clearances of 1 000 kV tension type towers
Figure D.39 \u2013 The arrangement of switching impulse flashover voltage testfor air clearances of 1 000 kV suspension I type towers <\/td>\n<\/tr>\n
101<\/td>\nFigure D.40 \u2013 The 50 % switching impulse flashover voltage characteristic for air clearances from conductor to tower body of 1 000 kV suspension I type towers
Figure D.41 \u2013 The arrangement of switching impulse flashover voltage testfor air clearances of 1 000 kV suspension V type towers <\/td>\n<\/tr>\n
102<\/td>\nD.4.3 50 % lightning impulse flashover voltage test results for air clearances of transmission line structures
Figure D.42 \u2013 The 50 % switching impulse flashover voltage characteristicfor air clearances of 1 000 kV suspension V type towers
Table D.7 \u2013 Gap coefficient k <\/td>\n<\/tr>\n
103<\/td>\nFigure D.43 \u2013 The 50 % Lightning impulse flashover voltage characteristicfor air clearance for 1 000 kV <\/td>\n<\/tr>\n
104<\/td>\nAnnex E (informative)Restrictions on electromagnetic environment ofUHV AC transmission lines in different countries
E.1 General
E.2 Restrictions in China
E.3 Restrictions in India
Table E.1 \u2013 Radio interference
Table E.2 \u2013 Audible noise <\/td>\n<\/tr>\n
105<\/td>\nE.4 Restrictions in Japan
E.4.1 General
E.4.2 RI (Radio Interference)
E.4.3 AN (Audible Noise)
E.4.4 Electric field
Table E.3 \u2013 Electric field
Table E.4 \u2013 Specific limits for noise of environmental regulation [dB(A)] <\/td>\n<\/tr>\n
106<\/td>\nE.4.5 Magnetic field
E.4.6 Communication failure due to electromagnetic induction or electrostatic induction
E.4.7 Overvoltage due to electromagnetic induction <\/td>\n<\/tr>\n
107<\/td>\nAnnex F (informative)Anti-vibration measures for conductorsand earth wires in different countries
F.1 General
F.2 Anti-vibration measures in China
Figure F.1 \u2013 Resonance frequency type vibration damper <\/td>\n<\/tr>\n
108<\/td>\nF.3 Anti-vibration measures in India
F.4 Anti-vibration measures in Japan
F.4.1 Conductor
F.4.2 Earth wire
Table F.1 \u2013 Upper limit of everyday tension and anti-vibration measures for galvanized steel strand or aluminium clad steel strand <\/td>\n<\/tr>\n
109<\/td>\nFigure F.2 \u2013 Shape of distributed damper <\/td>\n<\/tr>\n
110<\/td>\nAnnex G (informative)Earth wire regulations in different countries
G.1 General
G.2 Earth wires regulations in China
G.3 Earth wires regulations in India
G.4 Earth wires regulations in Japan <\/td>\n<\/tr>\n
112<\/td>\nBibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":"

UHV AC transmission systems – UHV AC Transmission line design<\/b><\/p>\n\n\n\n\n
Published By<\/td>\nPublication Date<\/td>\nNumber of Pages<\/td>\n<\/tr>\n
BSI<\/b><\/a><\/td>\n2021<\/td>\n114<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n","protected":false},"featured_media":385544,"template":"","meta":{"rank_math_lock_modified_date":false,"ep_exclude_from_search":false},"product_cat":[545,2641],"product_tag":[],"class_list":{"0":"post-385535","1":"product","2":"type-product","3":"status-publish","4":"has-post-thumbnail","6":"product_cat-29-240-20","7":"product_cat-bsi","9":"first","10":"instock","11":"sold-individually","12":"shipping-taxable","13":"purchasable","14":"product-type-simple"},"_links":{"self":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product\/385535","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product"}],"about":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/types\/product"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media\/385544"}],"wp:attachment":[{"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/media?parent=385535"}],"wp:term":[{"taxonomy":"product_cat","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_cat?post=385535"},{"taxonomy":"product_tag","embeddable":true,"href":"https:\/\/pdfstandards.shop\/wp-json\/wp\/v2\/product_tag?post=385535"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}