Plug-In Electric Vehicles’ Charging - University Of Maryland€¦ ·  · 2015-04-27Plug-In Electric Vehicles’ Charging ... Ford Focus EV $35,170 23 kWh Li-ion 6.6 kW OBC 76 mi

Plug-In Electric Vehicles’ Charging

Dr. Alireza Khaligh

Electrical and Computer Engineering Department Institute for Systems Research

University of Maryland College Park, MD 20742 http://khaligh.umd.edu/

April 2015

Engineering Sustainability Workshop

§  Current Statistics:

§  Transportation: §  Invention of Internal Combustion Engine (ICE), 150

years ago

TRANSPORTATION

POWER ELECTRONICS, ENERGY HARVESTING and RENEWABLE ENERGIES LAB !

§  Over 900 million vehicles worldwide

§  Over 250 million registered vehicles in the U.S.

§  50 million vehicles are being manufactured every year

§  Recent economic growth in China, India, elsewhere

POWER ELECTRONICS, ENERGY HARVESTING and RENEWABLE ENERGIES LAB !

TRANSPORTATION

§  Concerns: §  Rising fuel costs

§  Economic apprehensions

§  National security dreads

§  Environmental and public health

§  Transportation: §  Accounts for 40% of GHG and 70% of emissions

§  99% Dependence on ONE source of fuel

§  Not Sustainable

POWER ELECTRONICS, ENERGY HARVESTING and RENEWABLE ENERGIES LAB !

TRANSPORTATION ELECTRIFICATION

§  ELECTRIFICATION

§  Hybrid Electric Vehicles (HEVs)

§  Plug-In Hybrid Electric Vehicles (PHEVs)

§  Electric Vehicles (EVs)

ICE Vehicle HEVs PHEVs EVs

Transportation 2.0: Electrified Paradigm

Shift

*Specification data is based on public information and is subject to change.

Vehicle PEV type Price Battery On-Board Charger E-Range Connector type Level 2

Nissan leaf EV $21,300 24kWh Li-ion 3.3 kW / 6.6 kW OBC 84 mi SAE J1772 JARI/TEPCO 8 hrs / 4 hrs

BWM i3 EV $41,350 22 kWh Li-ion 7.4 kW OBC 81 mi SAE J1772 4-5 hrs

Ford Focus EV $35,170 23 kWh Li-ion 6.6 kW OBC 76 mi SAE J1772 3-4 hrs

Mitsubishi iMiEV EV $22,995 16 kWh Li-ion 3.3 kW OBC 62 mi SAE J1772 JARI/TEPCO 7 hrs

Honda Fit EV $37,415 20 kWh Li-ion 6.6 kW OBC 82 mi SAE J1772 4 hrs

Toyota Plug-in Prius PHEV $29,900 4.4 kWh Li-ion 3.3 kW OBC 11 mi SAE J1772 1.5 hrs

Chevy Volt PHEV $37,100 16.5 kWh Li-ion 3.3 kW OBC 38 mi SAE J1772 4 hrs

Cadillac ELR PHEV $75,000 16.5kWh Li-ion 3.3 kW OBC 37 mi SAE J1772 5 hrs

Fiat 500E EV $31,800 24 kWh Li-ion 6.6 kW OBC 87 mi SAE J1772 4 hrs

Ford C-MAX Energi PHEV $32,920 7.6 kWh Li-ion 3.3 kW OBC 20 mi SAE J1772 2 hrs

Kia Soul EV $33,700 27 kWh Li-ion 6.6 kW OBC 93 mi SAE J1772 4 hrs

Mercedes B-Class EV EV $41,000 28 kWh Li-ion 10 kW OBC 87 mi SAE J1772 3.5 hrs

Smart Electric Drive EV $25,000 17.6 kWh Li-ion 3.3 kW OBC 68 mi SAE J1772 6 hrs

Tesla Model S 60kWh EV $71,000 60 kWh Li-ion 10 kW OBC 208 mi SAE J1772 10 hrs (std charger) / 4

hrs (80 A charger)

VW e-Golf EV $35,000 24.2 kWh Li-ion 7.2 kW OBC 85 mi SAE J1772 4 hrs

ONBOARD CHARGERS FOR COMMERCIALLY AVAILABLE PEVS

Source: California PEV Collaborative (CG3-3).

Charging Level Power Supply Charging Power

Miles of Range for

1 Hour of Charge

Charging Time

BEV PHEV

Level 1 120VAC Single Phase

1.4 kW @ 12 amp (on board) 3-4 miles ~17Hours ~7 Hours

Level 2

240VAC Single Phase Up to 19.2 kW

(up to 80 amps)

3.3 kW (on-board) 8-10 miles ~7 Hours ~3 Hours

6.6 kW (on-board) 17-20 miles ~3.5 Hours

~1.4 Hours

Level 3 DC fast Charge

200 – 450 VDC Up to 90 kW (~200 amps)

>50 kW (off board) 50-60 miles

(~80% per 0.5 hr charge)

30~45 Mins

~10 Minutes

CHARGING POWER LEVELS

Configuration of an On-Board EV Charger

Vol

tage

[V]

2.5

3.0

3.5

4.0

4.5

5.0

Time [hour]0 0.5 1.0 1.5 2.0

Cur

rent

[mA

]C

apac

ity[m

Ah]

0

500

1000

1500

2000

2500CurrentVoltageCapacity

Constant Current Constant Voltage

0

1

2

3

4

320

360

400

440

480

State of Charge0% 20% 40% 60% 80% 100%

Cur

rent

[A]

Vol

tage

[V]

CurrentVoltage

Begin point

Nominal point

Turning Point End Point

CC CV

Onboard Isolated Charger

Parameters Value

Input voltage 85-180 V

Maximum input AC current 16 A

Power factor @ peak power ~ 99%

AC input frequency 55-65 Hz

THD at peak power < 5%

Overall peak efficiency 94%

Output battery voltage 320 V ~ 420 V

Maximum output power 1 kW

Output voltage ripple < 2 V peak to peak

Cooling Air

Operating Temperature -40oC to 105oC ambient

H. Wang, S. Dusmez, and A. Khaligh, “Maximum Efficiency Point Tracking Technique for LLC Based PEV Chargers through Variable DC Link Control,” IEEE Transactions on Industrial Electronics, in press.

Efficiency

Loss breakdown for critical operating points; a) conventional LLC; b) proposed LLC.

Efficiency of the LLC converter versus battery SOC.

Begin point Normal point Turning point End point0

5

10

15

20

25

Los

s(W

)

Switching lossesConduction lossesCore losses

Begin point Normal point Turning point End point0

5

10

15

20

25

Los

s(W

)

Switching lossesConduction lossesCore losses

(a) (b)

0 10 20 30 40 50 60 70 80 90 10065

70

75

80

85

90

95

100

ConventionalProposed

Eff

icie

ncy

(%)

State of Charge (%)

•  LLC Stage Efficiency Improvement at Full Load: 2.1%

•  LLC Stage Efficiency Improvement at Light Load: 9.1%

•  Overall Charger Efficiency Improvement at Full Load: 1.6%

•  Overall Charger Efficiency Improvement at Light Load: 6.7%

Off-Board Fast Plug-In Chargers

Different system level architectures for fast charging stations: a) Common AC bus link, and b) Common DC bus link

Off-Board Fast Plug-In Chargers

Off-board charger using high frequency isolated transformer.

4.2V

2.5 V

1 V

VTVrechg Ichg

Vpre

Vlpt Ipre

Iend

Batte

ry V

olta

ge

Cha

rge

Vol

tage

Pre-chargeat 0.1 C

Constantcurrent charge

Constantvoltage charge

ChargeComplete

Re-charge Chargecomplete

A

B

C D

Deeply Depleted Cell

Perspectives for Next Generation of Plug-In Chargers

§  Onboard Charger Topologies §  Isolated Chargers §  Integrated Chargers

§  Isolated §  Non-Isolated

§  Propulsion Machine/Inverter Integrated Chargers

§  Wireless Charging §  Static Charging §  Dynamic Charging

THANK YOU!