Oncor Electric Delivery Study on Residential Electric Vehicle Charging SWEDE Conference 2012 Ron Shipman
Oncor Electric Delivery
Study on Residential Electric Vehicle Charging
SWEDE Conference 2012Ron Shipman
2Oncor Electric Delivery
Introduction
•Impact of EV chargers on our system?
•Problems?
•Severity?
•Required Actions?
3Oncor Electric Delivery
Selection of Study Sites
Voltage (kV)
Peak Season
Area Year Built
Construction Characteristics
12.5 Summer Fort Worth 1965 Overhead (OH) w/ secondary
13.2 Summer Dallas 1965 OH parallel transformers w/ secondary
12.5 Summer Fort Worth 1976 Underground (UG) w/o secondary
12.5 Winter Plano 1979 UG w/ secondary (no flicker consideration)
24.9 Summer Round Rock 2006 UG w/ secondary
4Oncor Electric Delivery
Study Parameters
•Modeled Distribution System
•Coincident Peak AMS Data
•Simulated Chargers
Level 2 Charging
Penetration Levels
Multiple Scenarios
5Oncor Electric Delivery
CYME Subdivision Modeling
C
C
C
C
C
CC
C C
C
C
C
C
C
CC
C
CC
C
CC
C
C
C
C
C
C
C
B B
C
C
C
C
C
C
A
A
AA
Overview Map
6Oncor Electric Delivery
CYME Subdivision Modeling (cont’d)
•Maximum local transformer impedance
•Minimum service size
•Modeled Triplex
7Oncor Electric Delivery
AMS Generated 24-Hour Load Profile
Average Load Data
0
1
2
3
4
5
6
0:15
1:15
2:15
3:15
4:15
5:15
6:15
7:15
8:15
9:15
10:1
511
:1512
:1513
:1514
:1515
:1516
:1517
:1518
:1519
:1520
:1521
:1522
:1523
:15
Time of Day
Div
ersi
fied
Lo
ad [
kW]
Average Load
Average Load (Averaged)
SCADA Load per Cust.
8Oncor Electric Delivery
Results
•Fuse Loading
•Primary Cable Loading
•Transformer Loading
•Secondary Cable Loading
•Service Cable Loading
•Voltage Drop
•Localized Issues
9Oncor Electric Delivery
Locations EV and EVGO Requested
•2011 – 157 Locations
•2012 - 25 Locations to Date
•Addressed (2) Transformers
•Addressed (1) Secondary Cable
•Installed 19 EVGO Locations
10Oncor Electric Delivery
Questions?