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Extraction / Admission Steam Turbine Generator


PROJECT OVERVIEW:

GCS has supplied a turbine-generator control, monitoring, and actuation system for a large paper mill. The plant utilizes multiple turbines including this General Electric package rated for 28. 7 MW @ 3600 RPM. The plant Is run in parallel to the local utility in a droop base load mode.

The control system features the Micronet Digital Turbine Control Platform with custom application software performing functions including automatic turbine start and stop sequencing, speed control. admission/extraction control, and turbine protection. The Micronet hardware includes redundant power supplies and CPUs. In the event of a power supply or CPU failure, the control will automatically transfer control to the secondary CPU or power supply in a bump-less fashion enabling the turbine to continue to run until the appropriate module can be replaced. The system also includes an electronic over-speed protection device completely independent from the Micronet. This device utilizes three independent speed probes that trip the turbine only when two out of the three modules agree (2-out-of-3 voting). Similar to the Micronet hardware, the modules in this device can be changed while the turbine is on-line. GCS has included an automatic synchronizer with the system and packaged the controls in a single free – standing control cabinet.

Central monitoring and control is performed via a custom HMI system featuring dual touch-screen terminals. The HMls provide the operator with complete system control including starting and stopping of the turbine, synchronization, inlet steam valve control, and admission / extraction valve control.


TYPE OF FACILITY:
  • Paper Mill
TYPE OF PLANT:
  • Prime Power Generation Utility Paralleled in Droop Base Load
PRIME MOVER:
  • GE Steam Turbine Generator
    Single Extraction / Admission
    Inlet Pressure: 1500 psig
    Admission/Extraction Press: 600 psig 28.7 MW, 13.8 kV@ 3600 RPM
CONTROL TECHNOLOGIES:
  • Woodward MicroNet
  • Steam Turbine Digital Control System for speed control (governing), admission / extraction control, turbine protection, and monitoring. Micronet features redundant power supplies and CPUs.

  • Woodward ProTech GII
    Independent Over-speed Protection Device with two-out-of-three voting

  • Solenoid Trip Assembly
    Triple-Modular Redundant (TMR) turbine trip assembly

  • Woodward DSLC-2
    Generator Synchronizer and Load Control

  • Woodward UMT
    MW Load Transducer

  • HMI System
    Dual touch-screen terminals in the plant control room and control cabinet door for monitoring and control of the system including remote access.


HYDRAULIC ACTUATION SYSTEM


In addition to the control system, GCS has also supplied a new hydraulic actuation system for this turbine. This system includes a hydraulic power unit (HPU) skid, accumulator stand, rotary actuators for both V1 and V2, and accessories.

ACTUATION SYSTEM FEATURES
Duplex Hydraulic Power Unit (HPU)

  • Dual 7 HP Pumps Rated at 5 GPM & 1500 psig
  • Pressure Switching for Lead/Backup Arrangement
  • Thermostat Operated Heater
  • Oil to Water Heat Exchanger (Cooler)

  • Accumulator Stand
  • Four 15 Gal Gas Bottles with One 4 Gal Booster
  • Pre-charged to 1000 psig
  • Full 4 Gal of Oil Available to Operate the Actuators
    • Hydraulic Rotary Actuators: Parker HTR150
      • Dual Rotary Actuators for Turbine Valves V1 & V2
      • Voice Coil Servo Valves
      • Directly Coupled to Turbine Camshafts
      • Integral LVDT Feedback Devices
      • Full 360 Degree Stroke
      • Full 100% Rotation in Less Than One Second

    • System Accessories
    • Duplex Hydraulic Oil Filters
    • Oil to Water Heat Exchanger
    • Pressure Relief Valves



    TRIPLE MODULAR REDUNDANT {TMR) SAFETY TRIP

    Tripple Modular Redundant Satefy Trip Systems

    Control System Safety Features

  • Hardwired Relay Shutdown System Integrated into Control Cabinet
  • Heavy-Duty Industrial Grade Trip Relays
  • Triple Redundant Signals to Turbine Trip Valve
  • Independent ProTech 2-o-3 Overspeed Protection
  • IEC61508 SIL-3 Certified
  • APl670 & APl612 Compliant
  • Micronet Integrated Internal Turbine Protection
  • Interface to HMI System for Alarm and Shutdown Reporting Including First-Out Detection

  • TMR Trip Valve

  • Triple Independent Solenoids Integrated On-Valve
  • 2 out of 3 Voted Design
  • 24 Vdc Solenoids (110/220 Vac Available)
  • 50 - 300 psi Operating Pressure
  • POST INSTALLATION PHOTOS
    Cabinet:
    Cabinet Post Installation
    HMI Screen: Micronet Overspeed Test
    HMI Screen


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