Benefit of Siemens Technology Alternative Insulating Liquids

Transcription

1 Pomona, CA, May 24-25, 2016 Benefit of Siemens Technology Siemens AG Transformers

2 Environmentally-friendly and safer transformer insulating liquids Page 2

3 Why highlight alternative insulating liquids? Reach a higher level of personal safety Meet regulations regarding environment impacts Siemens provides proven equipment with appropriate designs - Siemens has been delivering ester units Distribution Transformers for over 20 years Power Transformers since 2004 Committees and publications on alternative insulating fluids - IEC (TC10) and CIGRE (WG D1) - Electric Today, Electra, ISH and others Page 3

4 Mineral Oil Synthetic Ester Natural Ester Produced from crude oil Hydrocarbon compounds - Paraffinic - Naphthenic - Aromatic - Olefin Derived from chemicals Product of alcohol with synthetic or natural acids Advantages - Oxidation stability - Thermal and environmental behavior - Biodegradability Made of plant seed oils Advantages - Higher flash and fire points - Biodegradability - Sustainable Page 4

5 Esters have a higher fire safety factor Esters are environmentally friendly Esters can extend the lifetime of the transformer Liquid immersed paper-aged open & closed to air Higher flash and fire point Fire point over 300 o C - K class rating (IEC 61039) Lower gas conversion factor - Tank rupture prevention improvement Readily / Fully biodegradable - In accordance with OECD 301 / IEC Classified as non-hazardous to water Slower decrease in the degree of polymerization Higher capacity to absorb moisture than mineral oil without compromising the dielectric properties Higher temperature limits Page 5

6 Current practices and developments Challenges to current transformer design Alternative insulation liquids have: Lower dielectric strength Higher viscosity and higher pour point in comparison to mineral oil Compatibility issues with new materials Special filling and impregnating requirements Alternative insulation fluids are also more expensive than traditional mineral oil. Solutions The different characteristics are considered in: ü Design adjustments ü Tailored cooling design ü Compatibility tests of materials ü Adapted procedure for impregnation and filling The benefits of a change to alternative fluids: Longer life cycle and higher temperature limits & increased safety, reduced insurance premiums and therefore a lower total cost of ownership. Page 6

7 How to cope with the higher price for ester? (CAPEX/OPEX benefits) FM Global (an international insurance company) recognizes the increased safety of these products by offering lower annual insurance premiums to its customers. Major construction impacts: FM and other companies only require 3 feet of spatial separation between approved transformers using alternative insulation fluids and buildings. Mineral oil transformer currently require spatial separation of up to 50 feet. As a consequence the generator bus bar losses are lower. Man hours needed for engineering and plant construction should decrease. Page 7

8 We can offer: Power transformers Up to 1300 MVA, 765 kv Natural ester, synthetic ester Distribution transformers e.g. 12,5MVA and 72,5kV Natural ester, synthetic ester, silicone fluids Environment Eco-friendly, fully biodegradable Renewable Safety High fire point, better gas conversion factor Lower insurance premium, lower construction cost Ageing Extended lifetime Enhanced temperature limits, efficient heat recovery Page 8

9 Challenges on transformer design 1. Lower dielectric strength in comparison to mineral oil 2. Higher viscosity (and only for natural ester: high pour point) 3. Compatibility with materials commonly used in transformers 4. Impregnation behavior of solid insulation 5. Higher electrostatic charging tendency (ECT) 6. Oxidation stability (specifically for natural ester) 7. Higher price than for mineral oil Solutions 1. Design adjustments - distances between windings and grounded elements, insulation design of oil ducts within barriers at winding end and lead arrangement has to be modified 2. Tailored cooling design 3. Compatibility tests of materials 4. Adapted procedure for impregnation and filling 5. Adjusted liquid flow velocities 6. Hermetic design 7. Benefits due to longer life time or higher temperature limits Page 9

10 Reference list Shipment Year Fluid Type Country f Rated Power Rated Voltage Cooling Type [Hz] [MVA] OS [kv] US [kv] 2004 Synthetic ester Sweden KFWF 2009 Synthetic ester Sweden KFWF 2011 Synthetic ester Sweden /100/ KFWF 2006 Natural ester Brazil ,8 KNAN 2008 Natural ester Germany KNAN 2009 Natural ester Brazil ,8 KNAN/KNAF 2013 Natural ester Germany / KDAF/KNAN 2015 Synthetic ester UK KDWF 2015 Synthetic ester Sweden /60/ ,8 KDWF Page 10

11 Siemens AG - Transformers Contact Martin Stössl Head Global Technology Centre LPT GTC Elingasse Weiz Austria Phone: +43 (51707) Mobile: +43 (664) martin.stoessl@siemens.com Siemens.com/transformers Page 11