Page Comparison

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• Position Control
  Operate to maintain Actual Position = Position Reference

• Speed Control
  Operate to move Azimuth at Speed Reference

Enclosure Azimuth motion during observation

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PLC Routine: Control Speed

Set Position and Speed Reference
Calculate Position Error
Set Tuning parameters based on position error (Homing, Tracking, Fine Tracking
Set Speed limits based on operating mode
Set response times for PI, signal filtering and output curve shaping
Calculate inflection point (change in direction) of Position Setpoint

PI (Proportional / Integral) closed loop control

Calculate PI output
Clamp maximum integral error
Clamp PI output
Add ECS speed reference
Clamp maximum speed output
Convert degrees / second to RPM

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