Rashtriya Chemicals and Fertilizers Limited Requirements for Upgradation and Addition for Load Management

System for their Captive Power Plant

 

 

Requirements

 

Upgradation of Allen Bradley PLC3 to Control Logix phase wise and Expansion of System over an elongated period to incorporate their Load Management System for their existing 100MW capacity Installed Generators. The Load Management System Logic Includes

  • Optimization of Generator Load.
  • Import Export Controller.
  • Certain Actions take place on over Frequency.
  • Constant monitoring of Maximum Demand load of Grid Supply.
  • Re-acceleration of Critical HT- Motors.
  • Under Voltage Management Scheme Within individual buses.
  • Sequence of Event Recording for Diagnostics.
  • Street Lighting with 1/3rd Lighting during twilight zones.
  • Others include: Reporting and Remote Monitoring with Plant Wide Area.

 

Challenges

 

 

Solution

  • No Previous Document. The Original System was installed in 1983 with 3600 I/Os had very limited document was available during the start of changeover.
  • Phase wise Migration to Spread over 10 Years. From Controller and Operator Station in First Phase to I/O Up-gradation Subsequently. This upgradation needed to be spread over a period of 10 Years due to Budget and Shutdown constrains.
  • Minimum LMS Downtime Time will be Given to ensure that LMS is blocked. Total 3 Phases for Processor and Operator Station with 8 Hrs. each downtime and 5 Phases of IO Panels of 1 Day to 5 Days for each Phase downtime of LMS Blockage.
  • Critical Scan Time: Critical part of the LMP is to maintain Very Low (100mSec) Scan times for Key operations.
  • High Availability Design. Any downtime can lead to Huge losses in the plant as it could lead to complete Plant Shutdown.
  • Addition of 1164 I/O’s intermediately and during Generation Capacity increment from 30MW to 100MW bringing total IO count to 4764. Additional Numerical Relays on 61850 & MODBUS devices needed to be added.
  • Complete Revision in Documentation and Revision in Logic to incorporate Client’s new Requirements.
  • Initial Changeover of only with Redundant Controller and ES + OS Stations keeping future expansion.
  • Server Client Architecture with Auto Changeover of Clients located at Different Locations.
  • Incorporation of Alarm Management and SOE / FIFO Event Recording Server with Remote Location Printing based on Events.
  • Phase wise Changeover of 11 I/O Panels distributed and then addition of 3 More Locations with Multiple Ethernet DLR Topology finally incorporated.
  • HMI Located at Various IO Panel Locations for Remote Monitoring and Limited Control
  • Connectivity to Plant Area Network for Remote Viewing for Associated Engineering and Plant Heads.
  • MODBUS communication for Power Meters and Temperature Scan on IO Ethernet Network and Direct DCS Connectivity.
  • Incorporation of 61850 Numerical relays with direct communication in the Controller.

 

Result

  • Knowledge of LMP helped in designing complete LMP for RCF Site with High Availability & Painless Commissioning.
  • Meticulous Design & Planning with Minimum Time for LMP Blockage and No Shutdown of Plant Operation the System was commissioned.
  • Original Planning to Help add further I/Os with Minimum Changes and Minimum Downtime.
  • I/O’s replacement started 10 Years after the Processor was originally upgraded giving very high Return on Investment.
  • Deign of system well planned to maintain all the derivable including Import Export Logic, Load Optimization, Under Voltage Transfer, Re-Acceleration of HT Motors.
  • SEO/FIFO Alarms, Reports, Remote Monitoring with Plant Wide Area.

Copyright MIPL 2019