Nuclear Power Plant Switchgear Retrofit
A nuclear power plant client at Siemens needed a section of their switchgear replaced due to flooding. Modern switchgear would not fit the existing location and thus required a custom-designed retrofit.
Problem
One of our nuclear power plant clients at Siemens needed a section of their switchgear replaced due to flooding. The flooded switchgear was installed 40+ years ago, so modern switchgear would not fit the existing location and thus required a custom-designed retrofit. However, because no other infrastructure was changing, the new switchgear layout and dimensions needed to stay the same as the old gear. This switchgear controlled cooling systems at the plant. The equipment needed to be manufactured and installed before the summer heat arrived, or the plant would have had to shut down. This timeline meant we only had one opportunity to replace the equipment.
solution
The team and I used copies of the original hand drawings from the 1970s and recreated the switchgear parts and assemblies in NX (Siemens proprietary CAD software). I then modeled a similar cubicle (an enclosure in which breakers are installed) and combined the switchgear parts and cubicles to recreate the exact layout of the current switchgear at the nuclear power plant.
Once an exact replica was modeled, I replaced the old gear with new/updated models to ensure everything fit correctly. The client wanted to upgrade the busbar from aluminum to copper during this retrofit. Copper busbars have different dimensions than aluminum, necessitating design modifications to the GPO-3 barriers that busbars pass through and to mounting heights to ensure contact between all busbar sub-assemblies.
I worked closely with the engineering field coordinator to produce the necessary documentation to assist the field technicians with the installation.
