Presentation February 2017 www.vimap-technics.com Moisture in - - PowerPoint PPT Presentation

Presentation

February 2017

www.vimap-technics.com

Moisture in power transformers

www.vimap-technics.com

Origin of water in power transformers

Depolymerization of cellulose

(Water is by-product of cellulose ageing)

Water from atmosphere

(Poor maintenance of air breathers and gaskets)

Water remained from production

(Appx. 0,5 % by celullose weight) Even if f a a transformer is s lea eak-free an and the oi

• il

l pr preserv rvation system is s per performin ing fl flawless ssly, , water is s PR PRODUCED as as a a BY-PRODUCT of

• f the nor

normal cell cellulo lose ag agein ing pr process!

www.vimap-technics.com

Distribution of water in power transformers

50 100 150 200 250 300 350 Water in oil Water in solid insulation Example: Power transformer 300 MVA at 50°C 60 t of oil with 20 ppm (µg/kg) water content  1,2 lit 10 t of cellulose with 3% water content  300 lit

About 99% of water in power transformer is stored in cellulose insulation while only about 1% is in the oil.

www.vimap-technics.com

Consequences of water in oil

EXCESSIVE WATER IN TRANSFORMER LEADS TO:

Accelerated degradation of complete insulation Reduced dielectric characteristics of insulation

Malfunction of power transformer

&

Reduced lifetime of power transformer

Reduced transformer resistance to electrical stress

www.vimap-technics.com

Water influence on power transformers lifetime

Power transformer lifetime is determined by lifetime of its cellulose insulation.

Ageing rate

Moisture accelerates ageing of cellulose insulation. Increase of water content in cellulose for 1% doubles the rate of its aging.

( , global leader in electrical insulation for transformer manufacturers)

Moisture content in solid insulation (%) 1 3 Insulation lifetime at 80°C (years) 40 10 1 10 100 0,1 1 10 3 % 30

Water content % www.vimap-technics.com

Permissible water content in power transformers

In the more recent IEEE Std C57.106 – 2002 (2) the permissible moisture level in paper is inferred from values of water content in oil, assuming thermal stability and moisture equilibrium between paper and oil Transformer rated voltage Maximum water content in oil ppm Equivalent water content in paper 50°C 60°C 70°C Up to 69 kV 27 35 55 3% 69 to 230 kV 12 20 30 2% 230 kV and above 10 12 15 1.25%

www.vimap-technics.com

Permissible water content in power transformers

Interpretation of moisture content by various standards and practices:

< 1 % As new 1 - 2 % Dry 2 - 3 % Moderately wet 3 - 4.5 % Wet > 4.5 % Excessively wet

Typical moisture content in cellulose insulation: New transformer: 0.5 % Aged transformer: 2 - 4 %

Normal increase of water content is typically 0.05 - 0.2 % per year.

www.vimap-technics.com

Mobil ile unit it for

• r in

insu sula latin ing oil

• il dehydration

VIM IMAP PORTABLE

St Stationary ry unit it for

• r on
• n-load tr

tran ansformer in insu sulation (o (oil il-celu lull llose) dryin ing

VIM IMAP RCID ID

www.vimap-technics.com

• Water from oil is adsorbed using granulated synthetic adsorbent

which bonds water molecules and permanently retain them in their pores as the oil is circulated through the dehydration vessel

• No oil vacuuming
• No oil heating

Operation principle

www.vimap-technics.com

New oil il must be drie ried prio rior to fill fillin ing in into th the elec lectr tric ical l equip ipment



Transformer oil delivered by the manufacturer is not dry and not suitable for filling into electric equipment



According to IEC 60296 new oil delivered in drums or IBC has a max. water content 40 ppm (mg/kg) while min. dielectric strength is 30 kV



Characteristics of new oil kept in drums, IBC or cisterns will further degrade with time due to improper storage, bad sealing, variation of ambient temperature.

Ne New oil

• il is

is not

• t dry oil
• il

www.vimap-technics.com

VIMAP PORTABLE – scope of application

• Suitable for on
• n-sit

ite de dehydration and filtration of insulating

• il in power and distribution transformers and tap changers
• De

Dehydration of

• f oil
• il in bar

barrels, IBC and for continual maintenance

• f dry oil in cisterns
• De

Dehydration of

• f ne

new oi

• ils

ls prior to filling into the electrical equipment

• Any oil manipulation or oi
• il

l tr transfer on

• n-sit

ite or

• r in wor
• rkshop

during the reparation

• Can be used simply as

as a a tr transfer pu pump (without drying)

www.vimap-technics.com

Oil Oil ch characteristi tics Un Unit it Be Before treatment Pass ss no no 1 Pass ass no no 2 Pass ass no no 3 Water content ppm pm 100 100 < 20 20 < 10 10 < 3 Di Dielectric ic strength kV kV 20 20 > 40 40 > 60 60 > 70 70

Quantity of oil in kilograms which can be dehydrated without replacement of adsorbent cartridges is about 50.000 kg, provided that there is no inlet of free water and tar into the

• device. Free water or tar draining from the bottom of tanks or transformers is required.

Typ ype Fl Flow w lit/h t/h Power con

• nsumptio

ion kW kW Dim Dimensio ions mm mm Ads Adsorbent capacit ity wi withou

• ut rep

epla lacement * Wei eight kg kg VI VIMA MAP – 6 0-600 600 0.55 594x878x491 50 50.00 000 110 110

VIMAP-6 PORTABLE - characteristics

• No oil inhibitors (antioxidant additives) removal

www.vimap-technics.com

VIMAP PORTABLE - configurations

VIM IMAP-6 PORTABLE (basic configuration)

• One vessel
• Adsorbent filling - 25 kg
• Water holding capacity - cca. 5 kg
• Gear pump 0-600 l/h
• Electric motor 0.37 (0,55) kW
• Contact manometer
• Frequency converter
• Switch off relay
• Particle filter 10 µm
• Frame with wheels mounted
• 2 x 5 m elastic hoses with Q.R.C.
• Bypass line (pumping without drying)

www.vimap-technics.com

MS MSP PORTABLE (additional to basic configuration)

• Two moisture sensors installed on inlet and outlet lines of the unit for measuring water

content in oil and adsorbents saturation control

• Display for continual monitoring of oil moisture (ppm) and temperature (°C) in both lines

VIMAP PORTABLE - configurations

www.vimap-technics.com

VIM IMAP PORTABLE is available in other configurations:

• Number and size of vessels/adsorbent quantity according to

request

• Customised design per specific application and customer

requirement

VIMAP PORTABLE - configurations

www.vimap-technics.com

VIMAP PORTABLE- Advantages

• Lo

Low ope

• peration cos
• sts

ts

• Hig

High efficiency in n oi

• il

l de dehydration

• Eas

asy ha handlin ing, g, transport an and main aintenance

• Su

Suit itable for

• r on-site ope
• peratio

ion or

• r in

n wor

• rkshop
• Min

inim imal ene energy consumptio ion

• Sa

Safe an and ec ecolo logical pr process

• No
• oi
• il

l he heatin ing

• No
• oi
• il

l vacu acuuming

• No
• oi
• il

l an antio ioxid idant ad additiv ives rem emoval

www.vimap-technics.com

VIMAP RCID

On Load (On Line) Power Transformer Insulation Dry-out Unit

Preventive maintenance Continual maintenance of low moisture level in both oil and cellulose insulation Corrective maintenance Reduction of moisture content in complete insulation Improvement of insulation characteristics Increase of power transformers safety and its lifetime

www.vimap-technics.com

No oil heating No oil vacuuming No antioxidant additives removing No dissolved gasses removing

• Designed for safe continual unattended
• peration on energized power transformers
• Water holding capacity appx. 5 kg each column
• Various numbers of columns

VIMAP RCID

On Load (On Line) Power Transformer Insulation Dry-out Unit

www.vimap-technics.com

Safety and monitoring elements

VIMAP RCID

On Load (On Line) Power Transformer Insulation Dry-out Unit

Sensors mounted on both inlet and outlet lines

• f the system display moisture contents (ppm)

and oil temperature (°C) and indicate adsorbents saturation level Ethernet board - working parameters are available via web browser or via email Moisture management system SCADA operated Oil leakage, air ingress and high/low pressure sensors shut the system off, isolating it from the transformer, in the event of any malfunction CMGSM module sends SMS notification Sound and visual alarm

www.vimap-technics.com

• Low investment costs
• Low operation costs
• Simple handling and maintenance
• No transformer operation interruption
• Safe transformer operation
• High insulating oil drying efficiency
• Depth drying of solid insulation
• Min. power consumption
• Remote monitoring of working parameters
• Environmentally friendly process
• Non-invasive process
• No oil heating
• No oil vacuuming
• No antioxidant additives removing
• No dissolved gasses removing

www.vimap-technics.com

VIMAP RCID- Advantages

www.vimap-technics.com

Questions?

Discussion

&