October 2nd, 2015Lab Meeting
Power Quality of a Solar Electric Vehicle Charging Station
Laura Novoa
© Advanced Power and Energy Program 2015 2/28
Agenda
• Motivation
• Overview of Car-Shade EV Charging Station
• Objectives
• Results of Power Quality Analysis
© Advanced Power and Energy Program 2015 3/28
MotivationJanuary
2015October
2015
© Advanced Power and Energy Program 2015 4/28
Car Shade System Overview
Switchgear
UCI Microgrid
20 EV Chargers
PV ArrayBattery
Inverter
100 kW/100kWh
Level 2 - 7.2 KVA 208 V (Dual-Phase)
48 kW
100 kW
12 kV
Car Shade Nanogrid
480 V
© Advanced Power and Energy Program 2015 5/28
Car Shade System Overview
Rooftop Solar PV Battery Enclosure
Charging Stations Battery and Controls
© Advanced Power and Energy Program 2015 6/28
AC to DC conversion in a Rectifier
AC Charger DC BatteryRectifier
EV Charging Grid Impacts
Harmonics
© Advanced Power and Energy Program 2015 7/28
Harmonics - What are they?
Dugan, 1996
Distorted Current Distorted Voltage
EV Charger(non-linear load)
Impedance
𝑉=𝑅 𝐼Ohm’s Law
Grid(source)
© Advanced Power and Energy Program 2015 8/28
Harmonics - What are they?
Distorted Waveform(combined harmonics)
Individual Harmonics Orders
FUND
3rd
7th
5th
9th
13th
11th
Fourier Transform
Dugan, 1996
© Advanced Power and Energy Program 2015 9/28
Harmonics - Why care?
• A generic distorted current with 3rd harmonic
𝑰𝟏𝑹𝑴𝑺=𝟕𝟎 𝑨
𝑰𝟑𝑹𝑴𝑺=𝟐𝟎 𝑨
𝑰 𝒕𝒐𝒕𝒂𝒍𝑹𝑴𝑺=√𝟕𝟎𝟐+𝟐𝟎𝟐 𝟕𝟑 𝑨
3A extra need to be supplied!
© Advanced Power and Energy Program 2015 10/28
Standards – How much is too much?
𝑇𝐻𝐷𝑣=√∑ 𝑉 h
2
𝑉 1
h=3,5,7…
Voltage: Total Harmonic Distortion
𝑇𝐷𝐷𝑖=√∑ 𝐼h
2
𝐼𝐿h=3,5,7…
Current: Total Demand Distortion
Thou Shalt Not Mess Up ThyNeighbor’s
Line VOLTAGE
IEEE 519
© Advanced Power and Energy Program 2015 11/28
Car Shade Power Quality Survey
Car Shade Nanogrid
© Advanced Power and Energy Program 2015 12/28
Objectives of Power Quality Survey
1. Characterize Power Quality at the Car Shade nanogrid– IEEE 519-1992 THDv limits
2. Validate ETAP harmonic flow model– Defined characteristic harmonic spectrum for different EV models
• Harmonic sources are modelled as current sources• Voltage Harmonics will vary according to the system impedance
3. Harmonic Cancellation
© Advanced Power and Energy Program 2015 13/28
Power Quality at the Car Shade Nanogrid
© Advanced Power and Energy Program 2015 14/28
Current Harmonics (Amps)
05/19/2015Tuesday
05/20/2015Wednesday
05/21/2015Thursday
05/22/2015Friday
05/23/2015Saturday
05/24/2015Sunday
05/25/2015Monday
05/26/2015Tuesday
0
1
2
3
4
Am
ps
A ITHDRss (avg) A I HG03 (avg) A I HG05 (avg) A I HG07 (avg) A I HG09 (avg)A I HG11 (avg) A I HG13 (avg) A I HG15 (avg) A I HG17 (avg) A I HG19 (avg)A I HG21 (avg) A I HG23 (avg) A I HG25 (avg) A I HG27 (avg) A I HG29 (avg)A I HG31 (avg) A I HG33 (avg) A I HG35 (avg) A I HG37 (avg) A I HG39 (avg)A I HG41 (avg) A I HG43 (avg) A I HG45 (avg) A I HG47 (avg) A I HG49 (avg)
Measured Current - Individual Harmonic Orders (3rd to 50th)
Memorial Day weekend
© Advanced Power and Energy Program 2015 15/28
0.00
1.00
2.00
3.00
4.00
5.00
6.00
2.84
1.530.89
1.81
0.521.00
0.50 0.30
95% Current Total Demand Distortion (TDD) and Individual Harmonic Distortion (IHD)
% IL
TDD 3rd 5th 7th 9th 11th 13th 15th
Current TDD
IEEE 519 -1992 LimitsTDD <5%< 11th <4%11th -17th <2%
• No individual harmonic orders registered or magnitudes above the recommended by IEEE 519-1992
Individual Harmonic Orders
© Advanced Power and Energy Program 2015 16/28
Voltage THD
05/19/2015Tuesday
05/20/2015Wednesday
05/21/2015Thursday
05/22/2015Friday
05/23/2015Saturday
05/24/2015Sunday
05/25/2015Monday
05/26/2015Tuesday
2.25
2.50
2.75
3.00
3.25
%
A VThd (avg) B VThd (avg) C VThd (avg)
1
2
3
4
5
Am
ps
A ITHDRss (avg) B ITHDRss (avg) C ITHDRss (avg)
Min Avg Max 95% A VThd 2.24 2.70 3.35 3.21 B VThd 2.16 2.57 3.11 2.91 C VThd 2.17 2.57 3.17 2.94
Measured Voltage - Total Harmonic Distortion (THD)
© Advanced Power and Energy Program 2015 17/28
0.00
1.00
2.00
3.00
4.00
5.00
3.12
0.20
1.982.24
0.10
1.030.52
0.07
95% Voltage Total Harmonic Distortion (THD) and Individual Harmonic Distortion (IHD)
THDv
and
IHDv
(%FU
ND)
THD 3rd 5th 7th 9th 11th 13th 15th
IEEE 519 -1992 Limits < 5%< 3%
• No individual harmonic orders registered or magnitudes above the recommended by IEEE 519-1992
Voltage THD
Individual Harmonic Orders
© Advanced Power and Energy Program 2015 18/28
Model a characteristic Harmonic input profile for different EV models
© Advanced Power and Energy Program 2015 19/28
Nissan Leaf - Charging Current Harmonics
Event #177 at 05/19/2015 09:39:59.800Timed
Timeplot
09:3005/19/2015
Tuesday
10:00 10:30 11:00 11:30 12:00 12:30
0
5
10
15
20
25
30
Am
ps
A Irms (avg)
Event #177 at 05/19/2015 09:39:59.800Timed
Timeplot
09:3005/19/2015
Tuesday
10:00 10:30 11:00 11:30 12:00 12:30
0.00
0.25
0.50
0.75
1.00
1.25
Am
ps
A ITHDRss (avg) A I HG03 (avg) A I HG05 (avg)A I HG07 (avg) A I HG09 (avg) A I HG11 (avg)A I HG13 (avg) A I HG15 (avg)
REGION 1 THDi = 0.9 A (3.1%)
REGION 2 THDi = 1.26 A (14.37%)
REGION 3 THDi = 0.7 A (20.97%)
Event #181 at 05/19/2015 10:19:59.800Timed
Event Details/Waveforms
10:19:59.8705/19/2015
Tuesday
10:19:59.88 10:19:59.89 10:19:59.90
-50
-25
0
25
50
Am
ps
A I B I
Event #187 at 05/19/2015 11:19:59.800Timed
Event Details/Waveforms
11:19:59.8705/19/2015
Tuesday
11:19:59.88 11:19:59.89 11:19:59.90
-15
-10
-5
0
5
10
15
Am
ps
A I B I
Event #191 at 05/19/2015 11:59:59.800Timed
Event Details/Waveforms
11:59:59.8405/19/2015
11:59:59.85 11:59:59.86 11:59:59.87 11:59:59.88
-1.0
-0.5
0.0
0.5
1.0
1.5
Am
ps
A I B I
Charging harmonic currents aren’t constant, thus:
Maximum (worst case) harmonics currents are considered for modelling each EV type
© Advanced Power and Energy Program 2015 20/28
Tesla - Charging Current Harmonics
Event #369 at 05/20/2015 16:19:59.800Timed
Timeplot
15:0005/20/2015Wednesday
16:00 17:00 18:00 19:00 20:00
0
5
10
15
20
25
30
Am
ps
C Irms (avg)
Event #369 at 05/20/2015 16:19:59.800Timed
Timeplot
15:0005/20/2015Wednesday
16:00 17:00 18:00 19:00 20:00
0.0
0.5
1.0
1.5
Am
ps
C ITHDRss (avg) C I HG03 (avg) C I HG05 (avg) C I HG07 (avg) C I HG09 (avg)C I HG11 (avg) C I HG13 (avg) C I HG15 (avg)
Event #377 at 05/20/2015 17:39:59.800Timed
Event Details/Waveforms
17:39:59.8805/20/2015
17:39:59.89 17:39:59.90 17:39:59.91
-50
-25
0
25
50
Am
ps
C I D I
THD = 1.7A (5.8%)
© Advanced Power and Energy Program 2015 21/28
3 5 7 9 11 13 150.00.51.01.52.02.53.03.54.04.55.05.56.06.57.0
Individual Harmonic Distortion (IHD) (%FUND)
Volt Leaf
Tesla Soul
BMW Mercedes
Prius Spark
Harmonic Order
% F
UN
DCurrent Harmonics Input – Different EVs
4.0
Recall:• IEEE Std 519-1992 • Individual Harmonic Order <4% for < 11th <2% for 11th – 17th
2.0
Single charging events present a higher distortion
Harmonic Cancellation takes place when a group of EVs is charging together
© Advanced Power and Energy Program 2015 22/28
Current Harmonics Cancellation
Cancellation is related to harmonic currents phase angles
• Total cancellation occurs when there is a 180° phase shift.
• Loads such as Electric Vehicles have similar harmonic inputs,
but when diversified across the phases, harmonics cancellation
will happen.
© Advanced Power and Energy Program 2015 23/28
Current Harmonics Cancellation5/
22/1
5 6:
00
5/22
/15
7:12
5/22
/15
8:24
5/22
/15
9:36
5/22
/15
10:4
8
5/22
/15
12:0
0
5/22
/15
13:1
2
5/22
/15
14:2
4
5/22
/15
15:3
6
5/22
/15
16:4
8
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0
20
40
60
80
100
120
Phase A at T1 Secondary
AI HG03Max[Amps]
AI HG05Max[Amps]
AI HG01Max[Amps]
Am
ps Am
ps
5/22
/201
5 6:
00
5/22
/201
5 6:
21
5/22
/201
5 6:
43
5/22
/201
5 7:
04
5/22
/201
5 7:
26
5/22
/201
5 7:
48
5/22
/201
5 8:
09
5/22
/201
5 8:
31
5/22
/201
5 8:
52
5/22
/201
5 9:
14
5/22
/201
5 9:
36
5/22
/201
5 9:
57
5/22
/201
5 10
:19
5/22
/201
5 10
:40
5/22
/201
5 11
:02
5/22
/201
5 11
:24
5/22
/201
5 11
:45
5/22
/201
5 12
:07
5/22
/201
5 12
:28
5/22
/201
5 12
:50
5/22
/201
5 13
:12
5/22
/201
5 13
:33
5/22
/201
5 13
:55
5/22
/201
5 14
:16
5/22
/201
5 14
:38
5/22
/201
5 15
:00
5/22
/201
5 15
:21
5/22
/201
5 15
:43
5/22
/201
5 16
:04
5/22
/201
5 16
:26
5/22
/201
5 16
:48
5/22
/201
5 17
:090
1000
2000
3000
4000
5000
6000T: EVSE 03 (W)T: EVSE 08 (W)T: EVSE 02 (W)T: EVSE 07 (W)T: EVSE 10 (W)
Pow
er (W
)
@10:40 Nissan Leaf connected EVSE 10 (AB)
No other EVSE disconnected
At this time, EVSEs 2, 3, and 7 were being used (phase A)
3rd80%
3rd17%
5th10%
5th70%
@14:30 Nissan Leaf connected EVSE 3 (AB)
At this time, EVSEs 2, and 7 were being used (phase A)
EVSE 3 LEAF
EVSE 10 LEAF
4 EVSE
3 EVSE
© Advanced Power and Energy Program 2015 24/28
25
50
30
210
60
240
90
270
120
300
150
330
180 0
Fudamental Frequency - 60Hz
Phase A EVSE 8
Phase B EVSE 8
Phase A EVSE 6Phase A EVSE 6
1
2
30
210
60
240
90
270
120
300
150
330
180 0
3rd Harmonic - 180Hz
0.25
0.5
30
210
60
240
90
270
120
300
150
330
180 0
5th Harmonic - 300Hz
0.5
1
30
210
60
240
90
270
120
300
150
330
180 0
7th Harmonic - 420Hz
0.1
0.2
30
210
60
240
90
270
120
300
150
330
180 0
9th Harmonic - 540Hz
0.25
0.5
30
210
60
240
90
270
120
300
150
330
180 0
11th Harmonic - 660Hz
Comparing: EVSE 8 (Leaf 1) and EVSE 6 (Leaf 2)
Different charging events will have different phase angles
Good for cancellation!Bad for modelling: No characteristic phase angles
Strategy: Did not model phase angles on ETAP model, but calibrate it to reflect cancellation
© Advanced Power and Energy Program 2015 25/28
ETAP Model THDv Results
© Advanced Power and Energy Program 2015 26/28
Summary
• Power Quality at the Car Shade– and thresholds are not exceeded at the PCC
• Phase angle diversity at the Car Shade allows for significant harmonic cancellation– Beneficial to Power Quality
• ETAP model validated – Calculated total voltage distortion at upstream buses in the system– Expansion effects (Future work)
© Advanced Power and Energy Program 2015 27/28
Acknowledgements
• Professor Samuelsen
• Professor Brouwer
• SCE and ETAP staff
• APEP Family
• Brazil SWB scholarship
© Advanced Power and Energy Program 2015 28/28
Questions?
© Advanced Power and Energy Program 2015 29/28
Backup Slides
© Advanced Power and Energy Program 2015 30/28
PQ Events at the Car Shade
• Impulsive transients (microseconds)
Event #453 at 05/21/2015 06:07:51.233BV Mult Z Cr Impulse
06:07:51.23505/21/2015Thursday
06:07:51.240 06:07:51.245
-150
-100
-50
0
50
100
150
Vo
lts
A V B V C V D V
Precisely at 6:07Nissan Leaf connects to EVSE 1
(CB)
• Oscillatory transients Event Details/Waveforms
07:19:59.8505/21/2015Thursday
07:19:59.86 07:19:59.87
-150
-100
-50
0
50
100
150
Vo
lts
A V B V C V
Precisely at 7:20Spark connects to EVSE 10 (AB)
© Advanced Power and Energy Program 2015 31/28
Chevy Volt - Charging Current
Event #389 at 05/20/2015 19:39:59.800Timed
Timeplot
09:0005/21/2015Thursday
10:00 11:00 12:00 13:00 14:00
0
5
10
15
20
25
30
Am
ps
C Irms (avg)
Event #389 at 05/20/2015 19:39:59.800Timed
Timeplot
09:3005/21/2015Thursday
10:00 10:30 11:00 11:30 12:00 12:30 13:00 13:30 14:00
0.00
0.25
0.50
0.75
1.00
Am
ps
C ITHDRss (avg) C I HG03 (avg) C I HG05 (avg) C I HG07 (avg) C I HG09 (avg)C I HG11 (avg) C I HG13 (avg) C I HG15 (avg)
Event #501 at 05/21/2015 12:09:59.800Timed
Event Details/Waveforms
12:09:59.8805/21/2015
12:09:59.89 12:09:59.90 12:09:59.91 12:09:59.92
-30
-20
-10
0
10
20
30
Am
ps
C I D I
THD = 1.0 A (6.8%)
© Advanced Power and Energy Program 2015 32/28
BMW i3 – Charging Current Harmonics
Event #1 at 05/18/2015 15:01:20.516Waveforms
Timeplot
10:2005/22/2015
Friday
10:40 11:00 11:20 11:40 12:00 12:20 12:40
-5
0
5
10
15
20
25
30
35
Am
ps
C Irms (avg)
Event #1 at 05/18/2015 15:01:20.516Waveforms
Timeplot
10:2005/22/2015
Friday
10:40 11:00 11:20 11:40 12:00 12:20 12:40
0.00
0.25
0.50
0.75
1.00
1.25
Am
ps
C ITHDRss (avg) C I HG03 (avg) C I HG05 (avg)C I HG07 (avg) C I HG09 (avg) C I HG11 (avg)C I HG13 (avg) C I HG15 (avg)
Event #651 at 05/22/2015 11:29:59.800Timed
Event Details/Waveforms
11:29:59.8405/22/2015
Friday
11:29:59.85 11:29:59.86 11:29:59.87
-50
-25
0
25
50
Am
ps
C I D I
THD = 1.3 A (6.8%)
Event #654 at 05/22/2015 11:59:59.800Timed
Event Details/Waveforms
11:59:59.8805/22/2015
Friday
11:59:59.89 11:59:59.90 11:59:59.91
-30
-20
-10
0
10
20
30
Am
ps
C I D I
© Advanced Power and Energy Program 2015 33/28
Kia Soul – Charging Current Harmonics
Event #654 at 05/22/2015 11:59:59.800Timed
Timeplot
10:0005/20/2015Wednesday
10:30 11:00 11:30 12:00 12:30 13:00 13:30 14:00 14:30
-10
0
10
20
30
40
Am
ps
A Irms (avg)
Event #654 at 05/22/2015 11:59:59.800Timed
Timeplot
10:0005/20/2015Wednesday
10:30 11:00 11:30 12:00 12:30 13:00 13:30 14:00 14:30
0.0
0.5
1.0
1.5
2.0
Am
ps
A ITHDRss (avg) A I HG03 (avg) A I HG05 (avg)A I HG07 (avg) A I HG09 (avg) A I HG11 (avg)A I HG13 (avg) A I HG15 (avg)
Event #344 at 05/20/2015 12:09:59.800Timed
Event Details/Waveforms
12:09:59.9005/20/2015Wednesday
12:09:59.91 12:09:59.92 12:09:59.93
-50
-25
0
25
50
Am
ps
A I B I
THD = 2.0 A (6.7%)
© Advanced Power and Energy Program 2015 34/28
Mercedes EV – Charging Current Harmonics
Event #343 at 05/20/2015 11:59:59.800Timed
Timeplot
12:0005/21/2015Thursday
12:30 13:00 13:30 14:00 14:30 15:00 15:30 16:00
0
5
10
15
20
25
30
Am
ps
A Irms (avg)
Event #343 at 05/20/2015 11:59:59.800Timed
Timeplot
12:0005/21/2015Thursday
12:30 13:00 13:30 14:00 14:30 15:00 15:30 16:00
0.0
0.5
1.0
1.5
2.0
Am
ps
A ITHDRss (avg) A I HG03 (avg) A I HG05 (avg) A I HG07 (avg)A I HG09 (avg) A I HG11 (avg) A I HG13 (avg) A I HG15 (avg)
Event #506 at 05/21/2015 12:59:59.800Timed
Event Details/Waveforms
12:59:59.8705/21/2015Thursday
12:59:59.88 12:59:59.89 12:59:59.90
-50
-25
0
25
50
Am
ps
A I B I
THD = 2.0 A (6.7%)
© Advanced Power and Energy Program 2015 35/28
Toyota Prius – Charging Current Harmonics
Event #1 at 05/26/2015 12:04:45.966Waveforms
Timeplot
06:4505/28/2015Thursday
07:00 07:15 07:30 07:45 08:00 08:15 08:30 08:45
0.0
2.5
5.0
7.5
10.0
Am
ps
C Irms (avg)
Event #1 at 05/26/2015 12:04:45.966Waveforms
Timeplot
06:4505/28/2015Thursday
07:00 07:15 07:30 07:45 08:00 08:15 08:30 08:45
-0.0
0.1
0.2
0.3
0.4
Am
ps
C ITHDRss (avg) C I HG03 (avg) C I HG05 (avg)C I HG07 (avg) C I HG09 (avg) C I HG11 (avg)C I HG13 (avg)
Event #271 at 05/28/2015 07:39:59.800Timed
Event Details/Waveforms
07:39:59.8805/28/2015Thursday
07:39:59.89 07:39:59.90 07:39:59.91
-20
-10
0
10
20
Am
ps
C I D I
THD = 0.4 A (12.3%)
Event #274 at 05/28/2015 08:09:59.800Timed
Event Details/Waveforms
08:09:59.8505/28/2015Thursday
08:09:59.86 08:09:59.87 08:09:59.88 08:09:59.89
-5.0
-2.5
0.0
2.5
5.0
Am
ps
C I D I
© Advanced Power and Energy Program 2015 36/28
Current Harmonic Phasors – Nissan Leaf 1 - EVSE 6
25
50
30
210
60
240
90
270
120
300
150
330
180 0
Fudamental Frequency - 60Hz
Phase A
Phase B
1
2
30
210
60
240
90
270
120
300
150
330
180 0
3rd Harmonic - 180Hz
0.25
0.5
30
210
60
240
90
270
120
300
150
330
180 0
5th Harmonic - 300Hz
0.5
1
30
210
60
240
90
270
120
300
150
330
180 0
7th Harmonic - 420Hz
0.1
0.2
30
210
60
240
90
270
120
300
150
330
180 0
9th Harmonic - 540Hz
0.25
0.5
30
210
60
240
90
270
120
300
150
330
180 0
11th Harmonic - 660Hz
© Advanced Power and Energy Program 2015 37/28
Switchgear
UCI Microgrid
20 EV Chargers
PV ArrayBattery
Inverter
100 kW/100kWh
Level 2 - 7.2 KVA 208 V (Dual-Phase)
48 kW
100 kW
12 kV
Car Shade Nanogrid
480 V
© Advanced Power and Energy Program 2015 38/28
Switchgear
Inverter
Battery100 kW/100kWh
20 EV ChargersLevel 2 - 7.2 KVA
208 V (Dual-Phase)
PV Array48 kW
100 kW
Car Shade Nanogrid
480 V
12 kV