Electricity and Control September 2021

TRANSFORMERS, SUBSTATIONS + CABLES

Advantages raise demand for dry-type transformers Cast resin dry-type transformers offer a number of advantages compared to traditional oil-based transformers, including safety, reliability, low maintenance and from an environmental perspective. David Claassen, Managing Director ofTrafo Power Solutions, speaking to Leigh Darroll at Electricity + Control , attributed the increasing demand for the company’s dry-type transformers – in various industry sectors across South Africa and other African countries – to these and other factors.

David Claassen, Managing Director of Trafo Power Solutions.

In the automotive sector Noting significant and welcome recent investments in South Africa’s automotive manufacturing sector, at the Ford plant in Silverton north of Pretoria, for example, and others such as those of Daimler Chrysler and VW well- established in Gqeberha and East London in the Eastern Cape, and Toyota in eThekwini in KwaZulu-Natal, Claassen said this has pushed up demand for its mini substations at automotive plants. Trafo Power Solutions recently supplied 10 transformers to one company in the automotive sector, to manage power supply to the plant and to support industries around it. Claassen highlighted the lower maintenance requirements and higher safety levels of dry-type transformers as particular advantages in the industrial environment. “Dry-type transformers have a Class F1 fire rating, which means they present no fire risk,” Claassen says. “They can be used internally in a factory, or externally. And with regard to the environment, there is no risk of an oil spill and therefore no environmental hazard.” Trafo’s mini substations (in which its dry-type transform- ers are used) offer another major

type transformers tend to be less targeted than traditional mini substations.

Transformers for data centres The shift from traditional oil-based transformers to dry-type transformers is also evident in the fast-growing data centre industry. In South Africa and other African countries, data centres are being established on home ground to handle the ever growing exchange of digital data and to better control compliance with domestic regulations. Distributed data centres also support safer data storage, more secure networks, higher transmission speed, lower risk, and lower transactional costs. Claassen emphasises that data centres have particu- larly high demands on power availability – requiring up to 99.9% uptime for their services and their customers. Here again the advantages of dry-type transformers in terms of the environment, safety and maintenance are important considerations. Data centres also present quite specific load characteristics and, with its experience in this environ- ment, Trafo is well positioned to meet these needs. The company has recently supplied transformers and mini substations to data centres in Gauteng and around Cape Town in South Africa. Mining, oil and gas Other major sectors that Trafo serves are the oil and gas industry and mining. In these sectors, lower maintenance and high safety are among the main drivers for the specification of dry-type transformers. These also contribute to a lower overall cost of ownership. Claassen highlights another advantage, especially for remote sites, is that dry-type transformers are constructed with a rigid frame. This means they are less susceptible to damage and can be transported over rough terrain, fully assembled and ready to be installed and commissioned on site. The rigid frame also suits mobile applications. Trafo supplies modular substations, mounted on skids, which can be moved around on a site to wherever they are needed, as they are less vulnerable to damages caused by vibration and shock than conventional oil-based transformers. The development of natural gas resources on the

benefit in the South African context in that they incor- porate inherent levels of protection against vandalism and theft. Firstly, because the transformers do not contain oil, there is no incentive for van- dals to drain oil from the equipment; and secondly, because the winding of the trans- formers is cast in res- in, would-be thieves cannot get access to the copper, aluminium or other metals used. Consequently, mini substations with dry-

A cast resin transformer housed in an IP56 enclosure, as typically used in the gas industry.

22 Electricity + Control SEPTEMBER 2021