April 27, 2012 Presented by: Andy Justice

1. SWEDE • Southwest Electric Distribution Exchange • “The Evolution of Distribution Switchgear” April 27, 2012 Presented by: Andy Justice

2. WHY USE SWITCHES ? Reliability Basics Switching & Manual Sectionalizing B1 S2 NC NC Breaker Switchgear 1 NC Loop system with sectionalizing switches 3-way Unit NO B2 S4 S3

3. Reliability Basics Switching & Manual Sectionalizing • WHY USE SWITCHES ? B1 S2 NC NC Breaker Locks Out Switchgear 1 NC 3-way Unit NO B2 S4 S3

4. WHY USE IT? Reliability Basics Switching & Manual Sectionalizing B1 S2 OPEN NC Breaker Locks Out Switchgear 1 NC Manual Sectionalizing Allows Faster Restoration of Power to Unfaulted Portions of the Underground Loop 3-way Unit CLOSE B2 S4 S3

5. Common Interrupting Mediums: Oil Air SF6 Vacuum Insulation Mediums: Air Insulated (AIS) Oil Combination Air and Gas Gas (SF6) Solid Dielectric Switchgear Design Overview Switchgear Design Overview

6. Air Switchgear Concerns Outages due to Corrosion, Animals, Dirt, Flashovers, Lack of Maintenance and Moisture Longer outage times to replace and upgrade Larger Equipment Footprint Solid Dielectric Design Principles

7. Oil Switchgear Concerns Oil is vaporized and gas extinguishes arc Old technology – Outages due to lack of maintenance and loss of insulation Environmental issue of Oil Spill Safety Concern/Risk associated with Fires Solid Dielectric Design Principles

8. SF6 Switchgear Concerns Outages due to loss of insulation, low gas pressure levels, low temperature and lack of maintenance. Environmental concerns – green house gases Difficult to fit into confined spaces Gas Disposal Issues Solid Dielectric Design Principles

9. Air, SF6 and Oil Switchgear Summary Larger Footprints Sensitive to Environment and Contaminates Frequent maintenance/monitoring Required Higher Risk of Failure Higher Risk of Fire Higher Costs for Maintenance Staff & Switching Longer Outages to Repair/Replace Solid Dielectric Design Principles

10. Desire for alternate mediums after WWII due to unavailability of Porcelain and Glass Insulators Epoxy Resin Current & Voltage Transformers were introduced in Europe in the 1947 In 1952 Polymer insulation casting was introduced in USA GE began a material study in 1954 & from there insulator trials began Ethylene-Propylene introduced in 1962 In 1965, Cycloaliphatic Epoxy was applied in outdoor applications In 1966, first few air-blast breaker insulators were made out of fiberglass reinforced Epoxy Since the 1960’s, EPDM rubber experienced rapid growth In 1996 Elastimold introduced the first Solid Dielectric Switchgear Design Solid Dielectric Design Principles Solid Dielectric Insulation Background

11. Dielectric strength Mechanical strength Impact strength Light weight Thermal shock resistance Tracking resistance Inertness to contamination & weathering Consistent and easy manufacturing processing Economic Reliability Solid Dielectric Design Principles Solid Dielectric Desirable Properties

12. Solid Dielectric Design Principles HIGH DIELECTRIC STRENGTH Example: 38kV 150 kV BIL Vacuum = ~1/2” Dielectric in Inches

13. Solid Dielectric Design Principles Overall Design Principles • SAFETY • RELIABILITY • OPERATIONAL FLEXIBILITY • ENVIRONMENTAL FRIENDLY

14. Solid Dielectric Design Principles • 1. Increased Safety • Dead-Front Construction – Insulated and shielded product with not high-voltage exposed components • Not dependent on oil, gases or air for proper isolation from high voltage • 2. Reliability • Utilizes Maintenance-Free Vacuum and EPDM Molded Insulation Technology which has over 50 years of field proven performance • Fewer Outages and significantly Lower Outage Durations • All Switchgear Components are Sealed and Fully Submersible

15. Solid Dielectric Design Principles • 3. Operational Flexibility • Compact and Lightweight Design allows installation in tight spaces • Modular Design allows combining with other devices • Interchangeable, Upgradeable, Customer Configurable • Less Inventory (Stock Common Components) • Non-Position Sensitive so it can be installed anywhere & in any orientation • Overall Lower Cost of Ownership • 4. Environmentally Friendly • No oils or gases to monitor, maintain or dispose of • EPDM Rubber is a GREEN solution; Contains no greenhouse gases, such as SF6

16. Switchgear Applications & Configurations

17. Typical Configurations Switchgear Applications & Configurations Padmount Subsurface Riser Pole Vault

18. New Modular Design Switchgear

19. New Modular Switchgear • New Modular Design Switchgear will provide solutions to: • Installations with confined vault spaces • Modular Design Retrofits • Ease of installation • Unlimited number of ways • Configuration flexibility • Upgradable • Provide Overall installation cost savings

20. New Modular Switchgear Standard Buses Bar Connection Load Switches Interrupters • Up to 35 kV rating for both Load-Break Switches and Fault Interrupting Devices

21. New Modular Switchgear Unlimited number of ways and configurations

22. New Modular Switchgear Modular Design Retrofits

23. New Modular Switchgear

24. Motor Operator Control

25. Motor Operator Control Motor Control System – Motor Installation

26. Motor Operator Control Motor Control System Overview

27. Control and Automation Advances

28. Control and Automation Advances Protection & Automation Controls Automation Controls Stand Alone Controls Auto-Transfer Controls

29. Switchgear Accessories

30. Automation Controls Voltage Sensors Components Voltage Sensor • Note: • No angle correction (offset) with Elastimold resistive style Voltage Sensors making them compatible with SEL Control Voltage Inputs. 200A Source Input Elbows Bushing Extenders for other phases w/o PT Cable Connection

31. Automation Controls • Start Up Connections: • Insert the Voltage Sensors into the 600A Elbow and tighten using a 600ATM Assembly Tool (See IS-1127). • Connect all the Voltage Sensors to the corresponding marked cables from the Switch Motor Box. • Note: • Connections are based on Motor Operator being supplied as a system. If Motor Operators are not packaged as a system, the Voltage Sensors will plug directly into the Control. Cables From Control Voltage Sensor Cables Cables From Motor Box Voltage Sensors Cables From Control

32. Automation Controls Voltage Sensors View

33. Automation Controls Solid Dielectric Deadfront Control Power Transformer Transformer 7000 -7620/116 127V (60:1 Ratio)

34. Summary of Switchgear Selection Considerations • Select State-of-the-art technology and suppliers with strong commitment to customer support. • Utilize Solid Dielectric insulation and vacuum switching/ interruption which translate into small footprint and maintenance free Equipment. • Specify that the Switchgear be fully submersible and feature deadfront construction for increased safety of operation. • Supplier needs to provide a wide range of configurations that fits multiple application needs and contributes to improve the reliability and operating performance of underground distribution systems. • Look for Modular Platforms and Designs in order to Maximum Flexibility and allow Future Expansion.

35. Advances in Underground System Automation • SWEDE • Southwest Electric Distribution Exchange Questions?