Xcel Energy Inc. · NASDAQ:XEL

Xcel Energy — Power Quality Webinar (September 2013)

17 slides from Xcel Energy's conference presentation, Sep 12, 2013

  1. Slide 1: Power Quality

    Power Quality Mary Santori, P.E. Senior Engineer September 12, 2013 1

  2. Slide 2: Topics discussed

    Topics discussed  Causes of Disturbances  Normal utility operations that can cause problems with sensitive equipment  How Xcel Energy works with customers on power quality issues  Reliability Key Indices and Outage Causes  Preventive Maintenance 2

  3. Slide 3: Causes of disturbances

    Causes of disturbances  On-site interference  Caused by loads inside a facility affecting the power in such a way as to cause other loads to malfunction  Neighboring interference  Caused by loads outside a facility affecting the power in such a ways as to cause other loads to malfunction  Natur

  4. Slide 4: Normal utility operations that can cause problems with sensitive equipment

    Normal utility operations that can cause problems with sensitive equipment  Protective devices operating under fault (i.e. breakers, fuses, reclosers)  Normal equipment operation (i.e. capacitor bank switching)  Single phase events (one phase of a three phase service is out) – Recommend phase pro

  5. Slide 5: Typical Electric Utility Distribution Layout

    Typical Electric Utility Distribution Layout From Transmission System Breaker Breaker Breaker Breaker Fuse 1 Fuse 2 Feeder A Feeder B XX Recloser Customer X Feeder C Fuse 3 Fuse 4 Customer Y Customer Z Feeder D 5

  6. Slide 6: Typical Electric Utility Capacitor Bank Switching Waveform at Customer

    Typical Electric Utility Capacitor Bank Switching Waveform at Customer 6

  7. Slide 7: Process for power quality issues

    Process for power quality issues  Gather background information from customer  Try and correlate disturbance to utility events  Set Recording Meters if Needed  Review Findings and Discuss Mitigations 7

  8. Slide 8: Step 1: Review Issue With Customer

    Step 1: Review Issue With Customer  What happened?  Dates and times (important to keep log)  Note anything else that happened in facility at the same time  Discuss customer’s electrical layout  If customer has monitoring, note location of meters (service entrance ideal) 8

  9. Slide 9: Step 2: Correlate Disturbance to Xcel Energy Electrical System

    Step 2: Correlate Disturbance to Xcel Energy Electrical System  If 0 volt condition, review outage logs  If voltage sag condition, review outages on transmission system and neighboring taps and feeders  If voltage sag or surge condition, review distribution lines device operation (i.e. capacitor

  10. Slide 10: Step 3: Set Recording Meters if Needed

    Step 3: Set Recording Meters if Needed  Monitor current and voltage at customer’s transformer or service entrance  Possibly monitor at neighboring customers 10

  11. Slide 11: Step 4: Review Findings and Discuss Mitigations

    Step 4: Review Findings and Discuss Mitigations  After reviewing monitoring data, may need to repeat Step 2  Note current and voltage relationship  Utility mitigation may include investigating malfunctioning equipment (cap bank, voltage regulator, etc..)  Customer mitigation may include installi

  12. Slide 12: Reliability Indices Reported to the MN PUC

    Reliability Indices Reported to the MN PUC (many different formats)  SAIFI – System Average Interruption Frequency Index  Total Number of Sustained Customer Interruptions Total Number of Customers  CAIDI – Customer Average Interruption Duration Index  Total Customer Minutes of Sustained Outages

  13. Slide 13: Outages Causes (by customer minutes)

    Outages Causes (by customer minutes) Minnesota YTD December 2012, Internal Normalization Method Includes Partial Restoration 18,000,000 100% Customer Minutes 16,000,000 90% Cumulative % n = 80,714,261 80% 14,000,000 Cu sto m er M in utes 70% 12,000,000 Cum u lative % 60% 10,000,000 50% 8,000,000 40%

  14. Slide 14: Preventive Maintenance Efforts

    Preventive Maintenance Efforts  Vegetation Management – Continual Condition Assessment/5-Year Maintenance Cycle  Infrared Testing – Semiannual Condition Assessment  Substation Transformers  Circuit Breakers  Surge Arrestors  Bushings  Regulators  Animal Control – Ongoing/Condition Based  Ca

  15. Slide 15: Customer Reliability Opportunities

    Customer Reliability Opportunities  Customer owned back-up generation  UPS  Auto or Manual Transfer  Phase Loss Protection  Transient Voltage Surge Suppression 15

  16. Slide 16: Power Quality Consultants

    Power Quality Consultants (Note: Xcel Energy does not recommend any one consultant)  EPRI, Mark Stephens, 865-218-8022  Hunt Electric, 651-646-2911  OlympiaTech, 763-559-1900  Parsons Electric, 763-571-8000  ColliSys, 763-535-6000  Hypertect, 651-631-0172 16

  17. Slide 17: Xcel Energy

    Qe Xcel Energy’ RESPONSIBLE BY NATURE™

Xcel Energy — Power Quality Webinar (September 2013) on 6ix