The turbo machinery control solution provided by DigiCon Systems is field proven at numerous plant sites around the world. The integrated solution incorporates turbine speed control, optimized anti-surge control for the compressor, load sharing, capacity control, and, incipient surge detection and control. The anti-surge control can be configured with a strategy that matches the application and transmitter data availability. The control solution also includes fallback strategies to provide utmost protection for the turbo machinery asset.

 

 

Application Areas

  • Compressor Control
    • Centrifugal Compressors
    • Axial Compressors
    • Centrifugal Blowers
    • Turbo expanders
    • Centrifugal Pumps
  • Turbine Control
    • Steam Turbines

 

Advanced Anti-Surge Control – Contributes to the ability to safely and efficiently operate the compressor

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Anti-Surge Strategies

  • Incipient Surge Override
  • Transmitter Fallback Algorithms
  • Digital Curve Fit (Look-Up Table)
  • Adaptive Gain
  • Surge Spike Detection & Prevention
  • Operating Point Tracking
  • PID Output Transformation
  • Surge & Capacity Decoupling

 

Incipient Surge Detection and Override Control –

  • Detects fluidic oscillations that occur as a precursor to surge
  • Independent of primary anti-surge control – serves as backup or override control

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Built-in Incipient Surge Algorithm

  • Current or Flow or Pressure Transmitter Input
  • High-speed Oscillation Sampler
  • Differential Input Band Pass Amplifier/Filter
  • Low Pass Filter
  • Absolute Value Converter
  • Peak Detector with Decay

 

Advanced Throughput Control – Integrated capacity control. Includes coordination between performance & anti surge

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Pre-Configured Performance Strategies

  • Automatic Loading: Runup – Rundown
  • Dynamic Decoupling (Capacity/Surge)
  • Pressure Constraint (Ps, Pd, DP, h, I)
  • Auto Process Variable SP Selection
  • Speed Effect Adaptation
  • Adaptive Gain
  • Anti-Stonewall Control
  • Integrated Process Control

 

Load Sharing and Optimization Control – Combination of equal-distance load balancing and load energy optimization

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Pre-Configured Load-Share Strategies

  • Equal % Load Sharing – Operates parallel compressors at equal percentage from their SCL’s
  • Mode/Permissive Status Monitoring
  • Auto Selection of Load-Valve Balancing
  • Efficiency Load Optimization – Constraint bias of equidistance load sharing based on energy consumption

 

Industrial Steam Turbine Control – Speed governor, power generation & steam extraction control for a wide range of  turbines

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Performance Strategies

  • Automatic sequencing of start-up, warming and stopping under constraints of critical speed avoidance
  • Preventive turbine over-speed via step control response
  • Control of optional variables – steam backpressure, extraction or throttle pressure
  • Controlling single or double steam extraction/induction
  • Restraining up to four process variables within safe or acceptable limits
  • Control valve steam flow vs. valve position characterization
  • Process turbine operation – Controlling turbine speed with local-remote setpoint
  • Power generation turbine operation – Synchronizing turbine-generator power with utility grid; Turbine-generator initial/base loading and soft unloading sequencing; Turbine-generator droop load control with power utility grid frequency correction.