Delay Compensation in a Feeder-Conveyor System Using the Smith Predictor: A Case Study in an Iron Ore Processing...

Area of Science:

• Mineral Processing Engineering
• Control Systems Engineering

Background:

• Conveyor belts are crucial for ore transport in mineral processing plants.
• Feeder conveyors regulate material flow, but control is hampered by measurement delays (dead time).
• This dead time causes oscillations and production inefficiencies.

Purpose of the Study:

• To compare control techniques for conveyor belt feeders with significant dead time.
• To implement and evaluate the Smith predictor against a PID controller in an operational plant.

Main Methods:

• Simulation-based comparison of various control strategies.
• Field implementation of the Smith predictor on a feeder conveyor.
• Comparative analysis with a Proportional-Integral-Derivative (PID) controller.

Main Results:

• The Smith predictor implementation resulted in a 355 t/h increase in production.
• Flow rate oscillations on the conveyor belt were reduced by 55% (standard deviation).
• Improved transient flow rate response during setpoint changes.

Conclusions:

• The Smith predictor effectively mitigates dead time issues in conveyor belt feeder control.
• This leads to substantial improvements in production efficiency and system stability.
• The Smith predictor offers a superior alternative to traditional PID control in this application.