MITSUBISHI ELECTRIC Changes for the Better
Sweden

Solutions for Roll Press

  • Large-capacity vector inverter
  • Roll press droop control
  • Stable high-accuracy tension control

Solution overview

IssuesSolutions
Stable drive of large-inertia rollsLarge-capacity vector inverter
Preventing synchronisation loss between roll pressesRoll press droop control
Stable tension controlStable high-accuracy tension control

Solution details

Stable drive of large-inertia rolls

The FR-A800 inverter series lineup includes standard products from 0.4 to 500 kW, and can support vector control by installing dedicated vector motors and vector control I/F.

When using vector control:

  • Speed response: 130 Hz
  • Speed variation: ±0.01%

Preventing synchronisation loss between roll presses

Dedicated droop control Function Block (FB) for roll presses performs correction of slave rolls to counter torque deviations due to differences in circumferential speeds of top and bottom rolls.

The system can handle interference torque in the high-speed region and speed fluctuations in the low-speed region.

Stable tension control

Stable high-accuracy tension control can be easily achieved using tension controllers. Torque control of powder clutches/brakes, AC servos, and vector inverters are all supported

  • For powder clutches, tension control is possible from almost-stopped line speeds
  • Tension fluctuations during acceleration are suppressed by calculating the material's moment of inertia and line speed.