BURNHAM TAYLOR TRANSMISSION CABLE PROJECT
Client: Exelon Corporation - ComEd
- Transmission line engineering and design
- Substation engineering and design
- Collection system engineering and design
- Material and equipment procurement support
- Construction field services
Scope of Work:
S&L's scope of work included engineering, design and construction management of:
- 6.2 miles of double-circuit XLPE transmission cable in downtown Chicago
- Installation of cable under the Chicago River, crossing of heavy-rail tracks, and under the Stevenson Expressway
- Modification and installation of GIS and AIS 345-kV terminations, inductors, and circuit breakers
- Scheduling, construction management, and commissioning support for the four substations and four transmission lines
- 345-kV XLPE terminations at Garfield Substation
Sargent & Lundy performed engineering and construction management for the installation of the 345-kV XLPE cable and reconfiguration of the HPFF cable systems between the Taylor Street 345-kV GIS and the 345-kV Garfield Terminal. The project included modifying the overhead connections and the installation of 345-kV series line inductors and breakers at Calumet Substation. The double-circuit transmission line ran from downtown Chicago south on State Street approximately 6.2 miles to Garfield Terminal.
The conceptual design for the addition of two 345 kV cross lined polyethylene (XLPE) cable circuits and the modification of the existing 345 kV high pressure fluid filled (HPFF) transmission infrastructure was a challenge in the selection of route, design of the conduit systems, and circuit design. The objectives for the project were to maintain the balance between a reliable and robust design that would minimize disruption of traffic during the installation of the conduit and cables.
On the substation work S&L provided electrical and structural engineering, grading design, support for procurement of material and equipment, construction quality control and substation commissioning services. Our transmission line scope of work included transmission line structure spotting, transmission line design and support for procurement of major materials.
Engineering design began in the spring of 2011 to design the 345 kV underground cable route, highway and railroad crossings. The project substation physical designs and protection and control upgrades were complete ahead of schedule to meet the aggressive schedule. The outage allowed for the cutover of the 4 major underground transmission circuits into the Downtown Chicago grid were from mid September 2013 to Mid January 2014.
The two HPFF circuit modifications, new GIS terminations, and joints were complete in two months, allowing for more time to complete the 345 kV XLPE installations. The circuits were commissioned and placed into commercial operation in early March 2014.