Team BUSS Backup Storage Source 1 Team BUSS

Team BUSS Backup Storage Source 1

Team BUSS Backup Storage Source EHV Substation Second DC Storage Source Sponsor Idaho Power Company Team Members Rob Butzer Mitch Colburn Brian Vandenburg 2

Presentation Outline Project Background n Customer Needs n Reliability Analysis n Alternatives Analysis n 3

Background In EHV substations, battery banks are used to maintain operational control of the substation when ac power is lost n The banks are able to control the relays and breakers, both used to help re-energize the system n 4

Present DC Battery Bank of up to 60 cells Each cell rated at about 2. 1 V Nominal Voltage of ~130 V 5

Present Battery Sizing Continuous load draws 5. 5 A for 8 hours to maintain station control Momentary load of 142. 8 A to be supplied after 8 hours for breaker control Minimum Voltage ~105 V 6

One Line Diagram Present System 7

Customer Needs 1. Calculate reliability of present DC battery system 2. Seek alternatives for a backup dc storage supply and evaluate added reliability 3. Implement scaled prototype on a bench top system 8

Present Fault Tree 0. 000068*525, 600 min/year = 35. 7 min/year 9

Parallel Batteries 10

Parallel Battery Systems 4. 624*10^-6*31, 536, 000 sec/year= 0. 146 sec/year 11

Alternatives Evaluation Basis: 1. Reliability 2. Cost 3. Maintenance 4. Life Expectancy 5. Size 12

Choice Matrix for Alternatives Initial Cost Maintenance Predicted Reliability Size Lifetime Weighted Sum Lead Acid Batteries(flooded) 7 5 10 7. 5 Battery + Ucap 6 8 7 4 8 6. 8 Generator + Ucaps 10 3 6 10 6 6. 65 Generator Set 9 1 8 7 7 6. 3 Ni. Cad Batteries 4 6 9 6 5 6. 3 Ultracapacitors 1 10 5 1 4 4. 75 Fuel Cells 2 9 1 4. 35 Flywheels 5 4 1 8 9 4. 25 Battery + Fuel Cells 3 7 4 3 2 4. 2 Compressed Air 8 2 3 3. 9 Dual Chargers 10 10 10 0. 25 0. 3 0. 1 10=best 1=worst Alternative Weight Scale: *red denotes estimate 13

Viability of Alternatives Handles Momentary? Handles Continuous? Weighted Sum Viable Alternative Lead Acid Batteries(flooded) yes 7. 5 yes Battery + Ucap yes 6. 8 yes Generator + Ucaps yes 6. 65 yes Generator Set yes 6. 3 yes Ni. Cad Batteries yes 6. 3 yes Ultracapacitors yes no 4. 75 no Fuel Cells no yes 4. 35 no Flywheels no yes 4. 25 no Battery + Fuel Cells yes 4. 2 yes Compressed Air no yes 3. 9 no Dual Chargers no no 10 no Alternative 14

Hybrid System: Battery & UCaps n n n Initial Cost: ~$1000 plus battery resized? Battery used for continuous Ucaps used for momentary 15

Hybrid System: DC Generator & UCaps n n n Initial Cost: ~$1500 Generator used for continuous Ucaps used for momentary 16

Bench Top System n The goal of the bench top system is to show the effectiveness of a hybrid system and how it may be implemented in a EHV substation 17

Bench-Top Testing This is the one line diagram for the bench-top system that is currently being designed 18

Project Timeline 19

Conclusion Discussion 20