National Seminar on New Generation High Performance Conductors. 4 th Dec 14

Transcription

1 National Seminar on New Generation High Performance Conductors 4 th Dec 14

2 Compulsion for alternative why? Limitation of power flow New line ROW Constraint Increasing urbanization left no inlet for critical S/S. EHV Cable cost still very high Use efficient conductor from day one Existing line (Overloaded/ Uprate the capacity) Replace/ Reconductoring with efficient conductor

3 What is efficient Conductor? ATTRIBUTES WHY 1) More current carrying capacity More power 2) High Conductivity (Low Resistance) Efficient power transfer 3) Temperature rise with current More I 2 R loss 4) Ultimate Tensile Strength Sag Tension compliance 5) Co-efficient of linear expansion limit Sag for ground clearance as per IE rules 6) Weight per meter Optimal loads for tower design 7) Cost Conductor contributes 40% of line cost

4 What GETCO is doing for new lines? Characteristics of various options: Options of conductor Benefits / Short comings Category Cost factor 1) ACSR Zebra (220 kv) 2) ACSR Moose (400 kv) Presently used Moderate Temp. Comparatively Low Presently used Moderate Temp. Comparatively Low 3) AAAC Lower weight, Higher Sag, Higher Resistance 4) TACSR / ZTACSR Higher Sag, Higher Resistance 5) ACSS Higher Sag, Higher Resistance 6) AL59 Higher Sag, Lower Resistance, Lower weight 7) CCC Lower Sag, Lower Resistance, Special T&P 8) Invar type Lower Sag, Higher Resistance 9) GAP type Lower Sag, Higher Resistance, Special T&P Moderately Higher Temp. (90 ⁰C) Higher Temperature ( ⁰C) Higher Temperature (250 ⁰C) Moderately Higher Temp. (95 ⁰C) HTLS (180 ⁰C) HTLS (230 ⁰C) HTLS ( ⁰C) Marginally High High High Marginally High Very High Very High High

5 What GETCO is doing for new lines? Adopted for 220 kv & 400 kv new lines. Options Available 1) Equal Diameter to ACSR 2) Equal Weight to ACSR Adopted - Equal Weight to ACSR Zebra (220 kv) - Equal Diameter to ACSR Moose (400 kv)

6 What GETCO is doing for new lines? (220 kv) Factors considered for decision making : 1) Current capacity required 170 to 200% of ACSR conductor 2) Project time Use of existing tower design, since new takes time. 3) Efficiency I 2 R loss 4) Satisfy Sag-Tension requirement with existing Tower Spotting Data 5) Dependency on supplier for hardware & accessories suitable for high temperature 6) Competency and T&P to handle erection of new conductor 7) Project cost (Deciding factor)

7 What GETCO is doing for new lines? (220 kv) How AL59 suited for decision making: Factors AL59 suitability Current capacity requirement Project time Efficiency Satisfy Sag-Tension with existing Tower Spotting Data Dependency for Hardware & Accessories Competency of erection Project cost Doubled with moderate Temperature rise (95 ⁰C) Suited to existing tower design Low I 2 R losses even@ 95⁰C Satisfied with 3 meter extension and by limiting the wind span Adequate Indigenous manufacturers Does not require special skill or T&P Increases by 10% appx.

8 What GETCO is doing for new lines? (220 kv) Comparison of options: PARAMETER AL59 (equal diameter to ACSR Zebra) AL59 (equal weight to ACSR Zebra) 1) Type 61/ /3.50 2) Diameter (mm.) ) Weight (kgs./km.) ) Cross section area (sq. mm.) 5) Resistance 20 0 c) (ohms/km.) ) UTS (KN) ) Wind Span (meters) ) Ampere Capacity

9 What GETCO is doing for new lines? (220 kv) Ultimate comparison with ACSR Zebra: PARAMETER ACSR Zebra AL59 (equal weight to ACSR Zebra) 1) Resistance 20 0 c) (ohms/km.) ) A.C. Resistance (@ maximum operating Temp.) 3) Ampere Capacity (AT 40 0 c) 4) Power Transfer capability in p.f per ckt. 5) Net Power Transfer for 100 km. line 0 c 0 c MW 373 MW 175 MW 350 MW

10 What GETCO is doing for new lines? (220 kv) Changes adopted to satisfy Tower Spotting Data: Options to counter higher sag at full temperature (95 0 c), 1) Reduction of Normal span 2) Use of extension permanently Practice adopted by GETCO 1) Use of extension permanently lesser cost & additional margin available for ground clearance. 2) Reduction in Maximum wind span to attend wind load increased due to diameter increase.

11 PROJECT COST (220 kv) ACSR Zebra conductor AL59 with +3 meter extension AL59 with reduced normal span Project Cost % %

12 What GETCO is doing for new lines? (220 kv) Conclusion: Double the Ampere Capacity & Net power transfer capacity by addition of appx. 10% to project cost and without operating line at excessive higher temperature. Low resistance compared to ACSR Zebra even at rated Temperature results in to lower loss for same power transfer & do not aggravate % Voltage Regulation. No special erection methodology, special tools tackles, special design Hardwares & Accessories required. Indigenous supply available for conductor and hardwares.

13 What GETCO is doing for new lines? (400 kv) Adopted AL59 for 400 kv New Lines. Options Available 1) Equal Diameter to ACSR Moose 2) Equal Weight to ACSR Moose Adopted - Equal Diameter to ACSR Moose.

14 What GETCO is doing for new lines? (400 kv) Comparison among options: PARAMETER AL59 (equal diameter to ACSR Moose) AL59 (equal weight to ACSR Moose) 1) Type 61/ /3.89 2) Diameter (mm.) ) Weight (kgs./km.) ) Cross section area(mm 2 ) ) Resistance 20 0 c) (ohms/km.) ) UTS (KN) ) Ruling Span(Sag-Tension) ) Wind Span

15 What GETCO is doing for new lines? (400 kv) Ultimate comparison with ACSR Moose: PARAMETER ACSR Moose AL59 (equal diameter) 1) Resistance 20 0 c) (ohms/km.) 2) A.C. Resistance (@ maximum operating Temp.) c 0 c 3) Ampere Capacity (AT 40 0 c) (130% higher) 4) Thermal Power Transfer capability in MW per ckt. (p.f. 0.95, factor 0.9) 936 MW 1220 MW (130% higher) 6) Project Cost 100% %

16 What GETCO is doing for new lines? (400 kv) How AL59 suited for decision making: Factors AL59 suitability Current capacity requirement Project time Efficiency Satisfy Sag-Tension with existing Tower Spotting Data Dependency for Hardware & Accessories Competency of erection Project cost Increased 30% with moderate Temperature rise (95 ⁰C) Suited to existing tower design Low I 2 R losses Satisfied with normal tower and by limiting the ruling span matching with actual field observation Adequate Indigenous manufacturers Does not require special skill or T&P Increases by 6-8% appx.

17 What GETCO is doing for new lines? (400 kv) Thermal capacity increased by 30% at increase of project cost 6-8% As the Sag at maximum operating temperature is increased, ruling span is reduced by appx. 7%. By retaining wind and weight span additional benefit of reduction in vertical load & longitudinal load added FOS for existing tower design.

18 CONDUCTOR COST Conductor Cost (Lac Rs./km.) Comparison ACSR Zebra ** ACSR Moose ** AL59 (61/3.50) % of Zebra 104.5% of Moose

19 GETCO Expectations Indigenous manufacturers conductor, hardware Availability of erection agencies Indigenous testing agencies Innovative erection technology e.g. live line Optimum cost

20 Thank You