The Direct Drive solution for paper machines reduces dramatically the need for mechanical drive components and space for paper machines by putting the motor directly coupled to the paper machine. Since the first installations 1999, the solution has proven successful for many paper mills all over the world.
The Direct Drive for Paper Machines
More mills and customers are starting with this technology and select the Direct Drive for their Paper Machines. The solution is a combination of AC or DC drives, traditional or new Permanent Magnet motors and both motor control and system control features designed for the Direct Drive. The current deliveries include over 250 permanent magnet motors and totally over 500 drive gearless sections altogether.
The Direct Drive is based to a slow speed motor with a permanent magnet rotor. The synchronous Direct Torque Control (DTC) motor control enables also tacholess operation in Paper Machines. The traditional AC motors are mostly directly coupled to the machine rolls, too. In addition to saving the gears with the Direct Drive, the permanent magnet motor can deliver also more torque from a smaller unit.
In many cases the decision for the Direct Drive has also been driven by the limited space around the machine. The space saved for other purposes is valuable. The Direct Drive impacts also to the machine life time runnability and costs through reduction of gear maintenance, lower noise level and less losses. Ultimately, the new technology significantly improves the overall efficiency of paper machines.