ACTOM Power Transformers “now ready”
After its successful completion of the design, manufacture and supply of four customised 60 MVA 12/132 kV power transformers as replacements for the original units in the City of Cape Town’s 180 MW Steenbras pumped-storage power station near Gordon’s Bay, ACTOM Power Transformers is well-placed to provide power transformers for power generation of all kinds.
“Our experience with designing and producing the replacement power transformers for Steenbras, as well as the 110/55/55 MVA unit transformers we have recently been contracted to produce for Eskom’s new Kusile coal-fired power station in Mpumalanga, place us in a strong position to provide power transformers for the full range of power generation applications – including the substantial wind farm project that Eskom plans to embark upon in the near future,” commented Ronnie Russell, the company’s General Manager.
ACTOM Power Transformers has been diversifying into manufacture of power transformers for power generation applications since completing an upgrade and expansion of its Wadeville, Germiston, plant in 2007, which extended its product capacity to an upper limit of 160 MVA at 132 kV, from its previous limit of 45 MVA at 132 kV.
The last two of the four replacement power transformers for Steenbras power station were delivered to site in April this year, following delivery of the first two in July last year and February this year respectively.
“What is particularly impressive about these conservatively designed units is that their performance capabilities are well in excess of the required specifications. The tests that have been done on them confirm that they have a 10% higher power capacity than specified,” Russell said.
Fibre-optic sensors were fitted at appropriate positions on the core and windings to measure Hot Spot temperature locations which would yield accurate results. This modern practice was incorporated into the specification by Element Consulting Engineers and the strategic positioning of these sensors was agreed upon between ACTOM and Element Consulting Engineers. The loading of the transformer can now be more accurately controlled thermally, which results in an increased lifespan.
The additional power capacity – effectively raised from 60 MVA to 66 MVA – results from the temperature rise tests that were conducted on them, which showed that they have the capacity to operate considerably cooler than specified. The transformers incorporate oil-forced and air-forced equipment for cooling.
“The improved cooling effectively raises the power capacity and therefore the transformers could be overloaded by 10% without any detrimental effect to them. In addition, as a direct consequence of this, the life of each of the transformers is extended by approximately 10 years to more than 40 years, rather than plus-30 years that is the accepted norm,” Russell explained.
“Furthermore, apart from the units being more efficient than specified, the cost of operating them will be considerably reduced compared with the originally specified performance requirements, due to the low load and no-load losses, as established in the tests that were conducted in the test facility at our plant, which were witnessed by the customer.”
The transformers were ordered in early-2009 by Consolidated Power Projects (CONCO) of Midrand, the electrical project management company contracted by the City of Cape Town’s Electricity Services Department to procure, install and commission them in place of the existing 55 MVA units, which were supplied by GEC Alsthom when the power station was built more than 30 years ago.
ACTOM (Pty) Ltd is the largest manufacturer and distributor of electrical equipment in South Africa, employing about 6 000 people and with an annual order intake in excess of R5bn. It is a black empowered company with 33 operating units, 27 production facilities and 28 distribution centres throughout South Africa.
ACTOM partners Alstom France for environmental equipment and in serving the maintenance, upgrade and retrofit market for larger boilers, as well as for railway transport activities.
ACTOM holds exclusive distribution, technology and representation rights for Alstom Grid (formerly the Transmission business of Areva T&D) in Southern Africa and maintains management, technical and commercial links to Alstom Grid business units in Europe.
Following the acquisition by Schneider Electric of the global Distribution business of Areva T&D, the distribution, technology and representation agreements that existed between ACTOM and Areva will remain in place until such time as a new agreement has been concluded.
ACTOM formerly traded under the name Alstom South Africa and re-branded to ACTOM in September 2009.
For further information contact Ronnie Russell, ACTOM Power Transformers
PO Box 14575, Wadeville 1422
Tel (011) 824-2810 Fax (011) 827-5116
Press release compiled by Julian Kraft, J Kraft Public Relations
PO Box 2826 Wilropark 1731
Tel (011) 472-6686 Fax 086-613-9657
Date: July 14, 2011
Caption: One of the 60 MVA power transformers is seen here on a lowbed trailer at ACTOM Power Transformers’ Wadeville plant ready for delivery to Cape Town’s 180 MW Steenbras pumped-storage power station.