Developments


Ferraris-Sensor/Disturbance Observer – a New Structure in Drive Control Technique


Development of a new type of control structure for direct drives in printing machines.

BHS 
BHS 
Print Cylinder Direct Drive
  • on the left in the machine
  • above in a test setup


Employment of a ferraris-sensor together with a disturbance observer.

The Ferraris-sensor delivers a high dynamic and high precision acceleration value, used by the disturbance observer, to determine the shaft-/load-torque of the drive.

The Ferraris-sensor is used here in a new kind of structure to observe and adapt another control circuit variable. Therefore this solution differs fundamentally from common applications with this sensor.

Through the combination of Ferraris-sensor and disturbance observer a key improvement of the control accuracy, especially of the disturbance reaction, was achieved. The influence of disturbances on the print quality was reduced significantly.

Position deviation caused by a cyclic torque impulse
   -  blue (F) common filter solution
   -  black (SB) new solution with deviation observer



Meanwhile the new structure is used very successfully in sophisticated, series manufactured printing applications.

Since the disturbance reaction plays a central role in many drive control applications, there are a lot of other possible utilizations, f. i. in machine tools.