Network ENMAX Power Corporation Network Planning & Design November 4, 2011
ENMAX Fast Facts Service area of 1,044 square kilometers 1,738MVA Peak load (2009) Transmission System 266 km overhead 15km underground 36 substations Distribution System 2,387km overhead 5,136km underground 64,554 utility poles 48,321 transformers
Network Service Boundary
ENMAX Network History 1910 Started installing conduit & manholes prior to paving 1912 Substation # 1 built to supply downtown load 1934 City council approves installation of a secondary network 1935 Secondary network started 1937 First 3-phase network transformer installed 1939 Secondary network expanded and 1 st in western Canada
ENMAX Network Section Secondary Network supplied via 3 major substations 13kV primary system, 56 feeders 3 voltages available 120/208v general street voltage 277/480v medium density loads 347/600v high density loads Remote Secondary Networks 3 major malls are supplied via secondary Network systems. Consist of 54 transformers with a load of 27 MVA. 25Kv High Voltage System 30 high density buildings supplied with a preferred and alternate 25kV feeder 2 substations supply the downtown 25kV system via 16 feeders. System configured such that a break before make transfer occurs within customer owned switchgear
ENMAX Network Fast Facts Secondary Network System Peak load of 230 MVA Service area of 8 square kilometers 875 transformers (500MVA installed capacity) 272 km underground primary HV cables (13.2kV) NO overhead primary 32kM secondary overhead cable 988 utility poles 1549kM underground conduit 653 km secondary system cable 343 street vaults 1300 manholes 410kM 3 rd party communication cable 25kV Downtown System Peak load of 130 MVA 30 major customers 50kM underground primary cables Secondary Spot Networks 3 large shopping malls (Chinook, North Hill and Westbrook) Peak load of 27MVA Supplied via distribution substations
What & Why a Secondary Network System Why Designed for high density loads Densely populated area s (impact of a power outage creates large scale socioeconomic impacts) Higher degree of reliability (n-2) is required or expected (Banking & Data centers) Permits equipment outages without impact to customers or switching operations What Composed of multiple transformers interconnected on the low voltage side Multiple primary feeders supplying the transformers Customers are supplied from the low voltage secondary interconnected grid Provides n-2 reliability (loss of any 2 components does not impact service)
Reliability Difference Total Outage Minutes Since 1994 #1 Substation 349 minutes Chevron fire (2002) 149 minutes, 26MVA load loss Century Gardens fire (2002) 121 minutes, 25MVA load loss Mission Gas Line (2005) 15 minutes, 23MVA load loss Miscellaneous substation incidents #5 Substation 9 minutes Miscellaneous substation incidents #8 Substation 60 minutes Miscellaneous substation incidents
Downtown Secondary Network Sub 8 Sub 5 8 Feeders 8 Feeders 8 Feeders 8 Feeders 13.2kV Q Buss 37 MVA 13.2kV R Buss 18 MVA 13.2kV 13.2kV Teens Buss 23 MVA 13.2kV Twenties Buss 25 MVA K Buss 40 MVA 13.2kV J Buss 32 MVA 8 Feeders 8 Feeders Sub 1 8 Feeders 13.2kV L Buss 44 MVA
Secondary Network - Sub 5 Example 138kV West Bus 138kV East Bus Street Grid 13.2kV Bus 21 22 25 26 27 28 23 24 Street Grid Street Grid 23 2 27 3 7 22 24 Man Hole 26 28 Street Grid 208V Customer Load STREET VAULT Customer Load STREET VAULT < 1200A Load Customer Load STREET VAULT STREET GRID Secondary voltages tied
Spot Network North Hill Mall Example Sub - 20 Sub - 003 Distribution Feeder: 8.20-18 Switchgear Distribution Feeder: 8.3-11 1A 2 3 208V 21B 7 1A 1A 1B 1B 1A 1B Switchgear Pad-mounted Designed to source spot network from one feeder at a time Upon loss of service to the primary feeder, control system is designed to transfer the spot network to the alternate source via a break-beforemake scheme. Customer Load STREET VAULT Customer Load STREET VAULT Customer Load STREET VAULT Note: Secondary's not tied together like a Street Grid
25kV High Voltage Radial System Open Sub 8 X3 feeders X3 feeders Preferred Alternate 25kV Customer Load 25kV Customer Load Preferred Alternate Alternate Preferred 25kV Customer Load 25kV Customer Load Alternate Preferred X3 feeders X3 feeders Sub 5 Open Sub 1
Network Servicing & Guidelines
Design & Records Tools Cost estimates produced utilizing Storms Design tool Byers MapViewer also used as a locating tool P&D enhanced the tool with the ability to view digital images as part of the records system. Microstation/Byers used for records and construction maps. Bubble system utilized to identify current construction projects Digital Grid used to determine current system status and load profiles for existing infrastructure
Network Monitoring System Originally installed in the early 1980 s System designed to monitor equipment status such as transformer load, voltage, power factor protector status (Open or Closed) water level, heat, smoke, temperature sensors SF6 gas pressure in system switches Operational staff utilize system to identify potential safety issues whenever a high voltage cable is de-energized to confirm if potential backfeed conditions exist Provides backup data for Engineering staff to develop Capital Maintenance programs. Assist design staff in identifying if a vault as sufficient capacity for additional customer loading
Screen shot of NCS viewer
NETWORK Field Pictures
Pre-Cast Vault & Installation
Street Vault Fancy Top
Street Vault Standard Top
Street Vault Fancy Top, Brick
Street Vault Fancy Top, Cement
Pre-Cast Manhole
Manhole High Voltage Connections (BLR)
Manhole High Voltage Connections (Splice)
Emergency Disconnect Switches E.D.D. (Emergency Disconnect Device) - 15kV switchgear which contains SF6 (Sulphurhexaflouride) - increased protection for equipment located inside the customer building - minimize impact of an event in the customer indoor vault on the system - enhanced safety for staff (Kill Push Button to de-energize vault in emergency)
25kV SF6 Switches
Network Major Office Tower Projects 8 th ave Place 16MVA @ 480-volt (2 Indoor Vaults) Encana (The Bow) 20MVA @ 600-volt (2 Indoor Vaults)
Door Signs on our Customer Owned Vaults
Postless Bus I-Beams
480 Volt Indoor Vault
600V Bus The Bow
Secondary HRC Fuse Boxes
Customer Service Fuseboards
Moles, close up
ENMAX Network Section Fibre Optics in the Network
Network Fiber Optic History 1990 1996 1999 installation of 1st fibre optic cable for Trans Alta Utility Shaw Fibrelink project starts in September and 36kM of backbone fiber installed in 4 months. ENMAX Network section performed all the fiber cable route planning and installation. GT Fiber project started an 12kM of 432 fiber backbone cable installed. ENMAX Network section performed all the fiber cable route planning and installation. Today ENMAX Network system contains over 110 km of fiber optic cable. We have a reputation for high quality work from design to installation.
Communication Cable Tagging
Network 101 Questions?
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