Decentralised drives will have `a tremendous impact`

Two out of five drives users in Europe expect to be using decentralised variable speed drives within three years, according to a new survey. Although the uptake of these systems has been limited so far, IMS Research, which conducted the survey, predicts that technology will have "a tremendous impact" on conveyor installations and in the automotive industry.

Decentralised drives are designed to be located next to the motor they control. IMS expects this technology to have a greater impact than motors with built-in drives, whose uptake so far it describes as "somewhat disappointing". After the initial optimism and excitement over the integrated motor-drives, "concerns over the reliability and price" have curtailed their acceptance.

According to IMS, the decentralised drives overcome two of users` key concerns about integrated systems: that heat and vibration from the motor will shorten the drive`s life; and that if either part fails the complete system will need to be replaced (despite the fact that many suppliers allow just the drive section to be replaced). The decentralised drives are also seen as being more flexible.

Europe is driving the move towards decentralised drives, with the US and Japanese markets lagging behind, says IMS. SEW Eurodrive is leading the trend and has helped to strengthen its position as one of Europe`s top ten suppliers of drives. Other suppliers include Lenze, Danfoss and Siemens.

Another new IMS survey, looking at trends in servo drives, also highlights the move towards distributed systems. More than a third of servo users quizzed by IMS expect to be buying servo motors with built-in drive and position control electronics within three years. Although such motors account for less than 2% of the European servo motors market at present, IMS predicts that they are "set to experience significant growth", but adds that they will remain a relatively small market.

More than half of the servo users interviewed expect to be using intelligent servo drives with integrated position control capabilities within three years. IMS does not expect this trend to spell the end for "dumb" servo drives, but points out that the smart drives have the attractions of being easy to set up, offering good performance, and fitting well into modular motion control systems.