Since the introduction of the world’s very first frequency converter in 1968, Danfoss has been at the forefront of drive technology. 40 years on, the company shows no signs of becoming complacent, and the recent announcement that they plan on gaining a foothold in the high power drives market simply strengthens this philosophy. Whilst the company has been manufacturing high power drives for 18 years, it has been the low and medium-powered drives (those up to 90kW) that have proved most successful. However, it is hoped that the investment and development of its high power drives, which are available up to 1.2MW, will bring even more success.
To aid with this, the ‘high power competency center’ - where the high power drives are manufactured - located at Loves Park in Rockford, Illinois, is set to undergo some major renovations. The $15m facility, which opened in 2001 and covers a total area of 11,400m², is to experience a 100% expansion that is set to be complete by August 2009. The project, which sees both floor and office space doubled, could certainly be attributed to the company’s recent success - that witnessed over 60,000 units being built last year. If this expansion wasn’t a definite statement of intent, then the fact that Danfoss has also purchased an adjoining 18 acres - which will allow for future expansion when the time is right - emphasises the notion even further. When the facility was acquired, it was done so “with the intention of building the high power range”, commented Peter Kartanos, product manager, high power drives.
To complement this impressive operation, Danfoss also utilises a ‘drive panel solutions’ facility in Milwaukee, Wisconsin. The custom-built drives (which account for all Danfoss high power drives) are transported to this nearby location, and are then subject to the engineering and integration of panels; of course, this is all dependent on the customer’s requirements. With over 35,000 panels built here last year, it seems likely that it will continue to aid the work taking place in Rockford.
For the last 18 years, Danfoss has been manufacturing its VLT (which is derived from ‘VeLo Trol’ or ‘VeLocity conTrol’) high power drives, making the 1MW+ variable speed range available four years ago. The existing VLT product range offers drives from “micro” sized up to 1.2MW, and from 200V up to 690V. They also have the option of being either central or motor mounted, and rated from IP00 through to IP66. “To be a global high power player, it is essential to offer the complete voltage range”, added Kartanos.
The VLT high power drives form part of a new high power production line platform, incorporating the latest design methods and components, offering compact IP00, IP21 and IP54 enclosures, and providing more factory designed, qualified and installable options. In addition, they meet all global standards, and have had full load testing of each converter. Since the introduction of these high power drives, more than 18,000 units have been installed globally.
Advantages of the high power drives include a complete voltage range (380-690V), built-in accessories (such as fuses, disconnects and RFI filters), an innovative air cooling system (back channel cooling), pre-engineered cooling arrangements for industrial enclosures, and a standard dc link reader for lower harmonics.
However, it could be argued that the most significant advantage is that the drives are more than 98% efficient at full load, whereas many competing systems only offer 97% efficiency. Whilst this one percent margin may not seem necessarily significant - especially when the numbers are as high as they are - the difference can lead to valuable energy and financial savings over a sustained period of time.
At this moment in time, there is simply more demand and orders for Danfoss high power drives than the company is physically able to fulfil. Unfortunately, there are some instances in which customers have to be turned away; a problem which will almost certainly be resolved on completion of the Loves Park facility development next year.
With every single drive being built to order depending on customer specifications, the company has also attracted interest – and substantial orders - from other drives manufacturers, who call on Danfoss when requiring a unique drive that is not simply available as an off-the-shelf option.
Sven Ruder, president of the motion controls division, commented: “We try to keep long relationships with our customers. It’s hard to get them and we don’t want to let them go”. Based on all the evidence, it seems as though the feeling is mutual.