Direct digital control systems&Software

IntroductionDDC Structure

The position algorithmThe velocity algorithm

Analog process

Direct digital control

DDC

• Centralized User Interface• ·Dynamic, Precise Facility Control• ·Coordination of Facility Systems Operation• ·Speed and Reliability from Computational

Power• ·Optimizing Facility Diversity• ·Durability and Flexibility• ·Troubleshooting/Easing of maintenance• ·Trending and History Data Logging• ·Customized Energy Reporting

DDC for chemical reactor

DDC structure

The Position algorithm

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The Velocity Algorithm

Two-Position Control

Two measure problems inVelocity algorithm

• CONTROLLER DRIFT

• Integral over shoot

Effect of set point band in Velocity algorithm

Benefits of DDC

• Improved Effectiveness

Improved Operational Efficiency

increased Energy Efficiency