SIS Case Study 2500A/12kV
INDUSTRY: Utilities, Municipal Power System
APPLICATION: switchgear bus tie
RATING: 12kV / 2500A per phase
BACKGROUND
Municipal utility system completing substation modernization and capacity upgrade, bus tie between switchgear, switchgear lineup, and feeds designed for increased reliability.
PROJECT DELIVERABLES
- Implement a new MV bus tie connection between switchgear lineups
- Highest capacity (current rating) per phase
- Custom design through interactive project development
- Scheduling coordination with other time-accelerated facility projects
- On-site construction supervision
SIS BUS BAR RATINGS and DIMENSIONS
- Rated voltage: 12kV, 50Hz, PFWV 28kV, 1.2/50μs 75kV (lightning impulse)
- Rated current: 2500A, ITHERMALSC 25kA for 3s, IDYNAMICSC 64kA
- AL conductor tube, diameter 90/15mm
- WEIGHT 15kg/m at OD 114mm (indoor)
- 190mm phase spacing
SIS SYSTEM CAPABILITIES
VOLTAGE CLASS (kV): 40.5
CURRENT RATING (A): 8000
General Specifications and Operating Requirements
- RESIN IMPREGNATED PAPER (RIP) technology
- Maximum system voltage and current
- Ambient temperature
- Routing and clearance
- Equipment connections and non SIS bus interconnections
- Indoor vs Outdoor installations
- Support structures to include seismic compliance
RIP technology has been used in the electrical industry for medium to high-voltage and EHV applications for over 50 years, mainly in the manufacture of high-current RIP transformer bushings.
Once the bus bar segments are manufactured according to proven RIP processes for vacuum impregnation and resin curing, each bus bar segment and connection sleeve is individually tested according to IEC 60137, Insulated Bushings for Alternating Voltages above 1000V (comparable to ANSI / IEEE C57.19.00 and IEEE C57.19.01) to ensure acceptable test levels for power frequency, partial discharge, capacitance, and loss factors. The test criterion is the essential element of verifying a void-free insulation structure that will lead to a partial discharge-free operation.
All RITZ SIS Bus Bar voltage class designs and current capacity ratings have been verified through type testing procedures, which are also covered under IEC 60137, according to the following test regimen:
- Power frequency test and PD measurements
- Impulse voltage test
- Power frequency test and PD measurements repeated
- Temperature rise test
- Temperature cycling
- Power frequency test and PD measurements repeated