Headquartered in Switzerland and with operation centres in the EU, MICAFLUID has a century-old heritage of extensive knowledge and experience in the power industry, making it a world leader in the engineering and development of insulating oil treatment, regeneration, and integrated systems.

Electricity is one of the most crucial discoveries in human history, providing comfort, encouraging inventions, and having huge importance fuelling our everyday life.

The most important enabler of all these possibilities are transformers, located on all branches of the power line. Yet, a great number of transformers in use are already at, or close to, the end of their lifecycle. The ongoing integration of renewable energy systems is causing fluctuations to occur more strongly and more frequently, endangering the stability of the system.

Essential to the life expectancy of any transformer is the state of its insulating oil. Not only is it an integral part of the oil and paper insulation system but it also serves to provide cooling and health indicators through oil analysis.

However, over time, the ageing rate of transformer oils, besides temperature, is accelerated by water, oxygen, and gas content, as well as acids derived from oil degradation. These, along with other contaminants adversely affect the dielectric strength of the oil, resulting in a lower Breakdown Voltage (BDV), propagating into a series of operational issues, which shorten the service life of the asset.

Insulation oil types and how to treat them

It is well known that the main oil ties in use today for insulations fall within the following categories:

  • Naphthenic-based mineral oil
  • Paraffinic-based mineral oil
  • Synthetic ester oil
  • Natural ester oil
  • Silicone oil

Each fluid has a different set of characteristics, which makes them better suited to certain applications, conditions, and cost.

Mineral oil is the most widely used insulation oil despite having some disadvantages due to its limited biodegradability and low fire point. It is important to avoid light fractions in a vacuum and thermal cracking during treatment.

Synthetic ester is chemically derived and optimised to have a higher fire point, as well as better water solubility and higher viscosity in comparison to mineral oil. Treatment, therefore, requires a higher process temperature, increased vacuum capacity, and specific process cycles to avoid poor treatment results.

Natural esters are vegetable-based fluids, which appear to satisfy the growing trend towards greener, more biodegradable fluids while presenting high flash and fire points. Its higher viscosity also calls for a higher vacuum capacity and more specific treatment parameters.

Silicone is a synthetic fluid, which has self-extinguishing characteristics with good thermal stability. It also requires increased heat and vacuum for treatment due to its extremely high viscosity. Furthermore, due to its non-compatibility with other fluids, treatment systems thrive to be dedicated to silicone oil treatment only, to avoid contamination of other oils.

MICAFLUID VOP treatment systems are prepared to treat all types of oils, and we are committed to delivering high-quality oil purification systems, which keep up with the latest developments in the world of insulation oils.

Furthermore, due to an array of technical features, which guarantee effective vacuum-tight treatment without the risk of microbubbles or contamination, MICAFLUID systems ensure process integrity without any compromises to the asset whether in a production line or substation.

21 advantages of using MICAFLUID technology in 2021

1. Efficient degassing with the single-stage vacuum

MICAFLUII3 plants require only the smallest suction capacity from the vacuum pumps as the operating pressure for effective degassing is between 1 mbar – 9 mbar.

2. Optimised electric heating system with horizontal configuration

The oil is indirectly heated and automatically regulated to within 1°C of the setpoint while ensuring a thermal flux of< l W / cm², which prevents hot spot cracking of the oil and guarantees its integrity.

3.  The complete system is vacuum tight

 The entire system is vacuum leak-tested with a guaranteed leakage rate of< 0.025 mbar • l / s, eliminating any entry of air into the process. No inlet feeding pump is, therefore, required for normal oil treatment.

4.  Variable flow-through

Due to an oil level control system, espe­cially developed by MICAFLUID, the oil flow is automatically adjusted to the flow-throughput setpoint without the risk of flooding. MICAFLUID systems are designed to ensure laminar flow on the outlet, which prevents the creation of microbubbles usually caused by turbulence.

5.  Thin-film degassing

The patented oil distribution system for maintenance-free thin-film degassing over the Raschig rings packed columns is known to be the most efficient method of dehydrating and degassing insulating oil. This had been proven in a study performed at the ETH Zurich.

6.  Automatic froth control

All VOP plants are equipped with an anti-froth control system. In case of unexpected foaming, the system detects and automatically reduces suction and flowthrough in the degasser without breaking vacuum. This helps the treatment of high viscosity oils.

7. Filtration with clog detection and automatic control

Three options for fine filters are used in MICAFLUID systems, namely nylon, polypropylene and fibreglass with varying characteristics, depending on the final application:

  • Beta X from 1000 to 5000
  • Nominal fineness from 0,35 µm to 5 µm
  • Temperature range up to 120°C.

Furthermore, clog detection enables early warning of a required filter change, which can then be performed safely during treatment without stopping or the introduction of air into the system and process.

8.  In-line gas and water content measurement

VZ212A applied on a VOP plant to measure water and total gas content.

9. In-line Tan Delta measurement

VZ220A applied on a VOP plant to measure Tan Delta.

10.  In-line breakdown voltage measurement with MicaSonic

MicaSonic applied on a VOP plant to measure:

  • Breakdown voltage [kV)
  • Moisture content [ppm)

(at 20°C and actual temp. as per IEC)

11.  Process supervision

All MICAFLUID plants are controlled by PLC, which automatically controls and supervises each operating step and provides process trend data and alarm history.

12.  Alarming

Essential to process supervision is the diagnosis and alarming. MICAFLUID systems generate information alarm dialogues both on the HMI and via SMS for immediate operator notification and action.

13.  Safety functions

Adhering to safety standards such as ISO / DIS 13849 – 1, MICAFLUID takes the safety of the operators, process, and system very seriously, and therefore, have standard features such as overpressure and temperature protection for the entire installation. Further features such as a leak or flood detection, dry run protection and phase sequence control ensure continuous fail-safe operation.

14.  Operator-friendly

With an intuitive touchscreen interface, the operation of any MICAFLUID system is simple, reducing the time needed for operator training.

15.  Industry 4.0

With the use of smart communication pro­tocols and sensors, MICAFLUID systems are prepared for full client-side integration, embracing the Fourth Industrial Revolution.

16.  Online treatment process on the energised transformer

MICAFLUID plants are prepared to per­ form on onload treatment of transform­ers, using the adaptable onload kit, which ensures a completely vacuum-tight pro­cess from start to end.

17.  IEC-compliant and energy-efficient

All units are IEC-compliant, achieving the required performance with efficient energy consumption.

18.  Low maintenance

The robust plant design requires min­imum intervention, limited to vacuum pump oil and filter change. Further­more, MICAFLUID units offer vac­uum-tight long-term storage even in high humidity corrosive environments.

19.  Spare parts guarantee

MICAFLUID offers outstanding spare parts and after-sales service during the lifecycle of the plants.

20.  Retrofittable accessories

Retrofit of all supplements or optional accessories, offered by MICAFLUID, can be installed by the customer without ad­ditional mechanical works on the plants.

21. Cost and travel reduction with MVA support platform

By subscribing to MICAFLUID’s machine virtual assistance (MVA) support platform, users have instant access to remotely control and supervise their machine, as well as direct Micafluid technical support and online diagnosis via secure sockets layer (SSL).

MVA quickly enables companies to remotely view and act on the oil treatment operation, reducing downtime, as well as travel and operator costs.

Furthermore, having the possibility to perform site or factory acceptance tests and training remotely, MICAFLUID is able to drastically reduce its carbon footprint.

Our range includes:

  • VOP – Variable Oil Purification CRP – Conventional Regeneration VPU – Vacuum Systems
  • OFP – Oil Filtration
  • HOS – Hot Oil Spray
  • ODS – Oil Distribution Systems