VIMAP RCIDOn-line power transformer dry out system

What is VIMAP RCID?

VIMAP RCID is on-line system designed for:

continuous unattended dehydration of transformers insulating system

VIMAP RCID – working principle

Dehydration is preformed by means of precisely selected granulated synthetic adsorbents, ie. molecular sieves which attract water molecules and permanently hold them in the pores of their active surface.

Pump draws insulating oil from the lowest point of transformer tank, circulate it through columns with granulated synthetic adsorbents and sends it back to the tank.

Illustration - Siemens AG

VIMAP RCID – working principle

Circulating transformer oil through columns with granulated adsorbents (molecular sieves) transformer oil is dried in a matter of hours or days.

Oil-cellulose insulating system tends to create state of equilibrium, i.e. tends to reach configuration with maximum entropy.

Disturbing moisture equilibrium by continuous oil drying, diffusion of water from the wet cellulose insulation to already dried oil is achieved, thus slowly removing the moisture from solid insulation.

Cellulose insulation drying is far slower process than oil drying and cannot be significantly influenced at.

CONVENTIONAL METHODS OF OIL DRYING

Oil dehydration has only short term effect on dielectric properties of oil and none on dielectric properties of cellulose

VIMAP RCID – Field of applications

Preventive maintenanceNew or previously dried power transformers- continual maintenance of low level of moisture in both oil and cellulose insulation

Corrective maintenanceTransformers with increased content of moisture- reduction of moisture in complete insulation, improvement of insulation characteristics, increase of power transformers safety and its lifetime

VIMAP RCID – Main features

No oil heating - no undesired effects from oil heating on overall oil quality

No oil vacuuming - no other parts to maintain or protect - longer equipment lifetime

No oil inhibitor removed

No dissolved gasses removed for continuous trending of important fault diagnostic gasses

VIMAP RCID - Construction & technical characteristics

Designed for safe continual unattended operation on energized power transformersHanging frame, bolt down stand, cabinet or wheels mountedVarious numbers of columnsWater holding capacity – appx. 5 kg each columnParticle filter 10 μm

VIMAP RCID – Safety and monitoring elements

Sensors mounted on both inlet and outlet lines of the system display moisture contents (ppm) and oil temperature (°C) and indicate adsorbents saturation levelOil leakage, air ingress and high/low pressure sensors shut the system off, isolating it from the transformer, in the event of any malfunctionSound and visual alarm

Optional:Ethernet module– working parameters are available via web browser or via email(SCADA compatible)GSM module sends SMS notification

VIMAP RCID- Advantages

Depth on line drying of solid insulation

High on line oil drying efficiency

No dissolved gasses removing

No antioxidant additives removing

No oil vacuuming

No oil heating

Environmently safe process

Min. power consumption

Remote monitoring of working parameters

Safe transformer operation

No transformer operation interruption

Simple handling and maintenance

Low investment costs

Low operation costs

VIMAP RCID – Safety features

AIP – Air Ingress Prevention

AIP consist of deaerating vessel and gas relay.Oil enters the deaerator in the upper zone and exits it from the lower zone. Unwanted air will therefore remain in the upper zone of the deaerator and will stream further upward to the gas relay wherein is collected. When volume of accumulated air in gas relay reaches 100 ml, electrical signal will stop the motor pump and trigger the alarm. Appropriate warning information will be displayed on the HMI.Solenoid valve will close immediately if installed. This way transformer will be disengaged from VIMAP RCID.

AIP is the last element of VIMAP RCID discharge line

VIMAP RCID – Safety features

High / Low Pressure Detection

Pressure transmitter monitors pressure change throughout the discharge line of the Unit. It will turn the unit off and start the sound alarm when pressure reaches previously set high / low limits. Appropriate warning information will be displayed on the HMI.Solenoid valve will close immediately if installed. This way transformer will be disengaged from VIMAP RCID.

Pressure transmitter is installed immediately after the pump.

VIMAP RCID – Safety features

Oil Leak Detection

Capacitive sensors mounted on dual containment hoses (between inner and outer hose) provide information in case of loose connections or hose break.When VIMAP RCID is installed in the cabinet additional capacitive sensor is located at the bottom of the unit and will detect any oil that is collected in the drip pan in case of leak.In both cases signal from capacitive sensors will turn the unit off and start the sound.Appropriate warning information will be displayed on the HMI.Solenoid valve will close immediately if installed. This way transformer will be disengaged from VIMAP RCID.

VIMAP RCID – Safety features

Particle filter saturation

Pressure switch – installed in front of particle filter. When pressure on particle filter reaches 1.7 bar appropriate information will be displayed on the HMI.Particle filter bypass valve - integral part of filter head and will be opened when differential pressure on particle filter reaches 1.75 bar.

VIMAP RCID – Adsorbent saturation

Two moisture sensors are installed in the Unit -one at the inlet and other at the outlet. Each of them continuously measure moisture contents (ppm) and oil temperature (°C).It is recommended to replace dehydration cylinders when the inlet reading is above 10 ppm and outlet reading is very close or same for a period of minimum 48 hours.

Outlet moisture & temperature transmitter installed in front of

deaerator

VIMAP RCID F – Frame mounted

VIMAP RCID F is frame mounted system for continuous dehydration of transformer insulating system.Can be equipped with one or more vessels.Water retaining capacity from 5 liters and more, depending on number of vessels.Pump flow from 90 l/h and more, optionally regulated by frequency converter.Moisture management system SCADA operated.Sensors mounted on both inlet and outlet lines of the system display moisturecontents (ppm) and oil temperature (°C) and indicate adsorbents saturation level.Ethernet board– working parameters are available via web browser or via email.CMGSM module sends SMS notification in case of unit malfunction.

VIMAP RCID M – Mobile trolley

VIMAP RCID M is mobile trolley system for continuous dehydration of transformer insulating system.Can be equipped with one or more vessels.Water retaining capacity from 5 liters and more, depending on number of vessels.Pump flow from 90 l/h and more, optionally regulated by frequency converter.Moisture management system SCADA operated.Sensors mounted on both inlet and outlet lines of the system display moisturecontents (ppm) and oil temperature (°C) and indicate adsorbents saturation level.Ethernet board– working parameters are available via web browser or via email.CMGSM module sends SMS notification in case of unit malfunction.