Electric Utility Projects

Electric Utility Projects

138kV Relay Upgrade

Project involved the replacement of various electromechanical relays with digital relays. New relays included two SEL-487B relays for bus differential relaying, which replaced the existing GE-PVD relays, and three SEL-351S relays for breaker failure relaying. All new relays were programmed and commissioned as part of the project. The scope of the project included:

  • Updating existing drawings to show relay upgrades, which included updating the one-line, AC/DC drawings, wiring diagrams and panel elevation drawings.
  • Working closely with panel vendor to ensure the panels were fabricated per the requirements of the project.
  • Programing all the new digital relays for the project, including the SEL-487B and SEL-351S relays.
  • Generating a step-by-step construction sequence document detailing the order that each circuit was to be modified.
  • Developing a commissioning plan to fully test and commission the new additions.

230kV Circuit Switcher and Switch Replacements

Project included the replacement of an existing 230kV circuit switcher with a 230kV live tank breaker. As part of the project two 230kV switches were also replaced. Most of the existing cables were re-used for this project. The scope of the project included:

  • Updating the one-line diagram to show the replacement of the circuit switcher with a live tank breaker.
  • Developing control schematics for the control/operation of the live tank breaker.
  • Generating elevation drawings for the relay panels associated with the live tank breaker.
  • Updating the annunciator with alarms from the breaker, and adding switch and breaker status along with the new relay alarms to the annunciator.

69kV Line Relay Replacement

Project included the replacement of electromechanical relays with microprocessor-based relays, which provided primary and secondary protection to the 69kV sub-transmission line. The project also involved the installation of a new Remote Terminal Unit (RTU) and bringing all existing and new data points to the RTU. The scope of the project included:

  • Replacement of electromechanical line relays with an SEL-311L relay, which was the primary relay and performed current differential relaying, and an SEL-421 relay, which served as the secondary relay and performed impedance-based protection of the line.
  • Updating the relaying one-line, DC/AC schematics and wiring diagrams to reflect the relay replacements.
  • Developing Remote Terminal Unit (RTU) drawings along with all the data points at the substation.
  • Creating fiber patch panel drawings for OPGW connection of the line relays at both line terminals.
  • Performing IEEE 485 based battery calculation for the substation.
  • Working closely with the testing crew for the commissioning of the new installation.

115kV Substation Relay Modernization

Project involved working with the client to develop a new protection philosophy to be implemented at a company-wide level. This new philosophy was implemented during the modernization project, which involved the installation of bus protection, transformer protection and various breaker failure relaying. The scope of the project involved:

  • Development of a new protection philosophy to be implemented at a company-wide level.
  • Generation of relaying one-line, elementary and wiring diagrams based on the newly developed relaying philosophy.
  • Creation of the bill of materials for the project and ensuring all the materials were from client approved vendors.
  • Performing battery sizing for the project to ensure the existing battery system could support the new relays for the project.