PHEV Testing

SAE J1711-revision
Session 2A: Initial Standards and Requirements

ver.2

Mike Duoba, Richard Barney Carlson, Ted Bohn, Daniel Bocci, Steve Gurski Argonne National Laboratory Advanced Powertrain Research Facility
Vehicle Technologies Program

Background SAE J1711

Original J1711 First Approved in 1999 Included PHEV testing, but never validated with PHEV hardware Consensus Changes to Original J1711 to date Do not combine fuel and electricity into a composite MPG Result
Report both MPG and AC Wh/mi (from plug)

Baseline charging assumption: 1 charge per day

Missed charge = Opportunity charging

Retain Utility Factor method of combining depleting with sustaining Emissions certification may not be the same procedure as fuel economy determination

Todays Test Procedure For Hybrids FTP and HWY

U = UDDS Cycle H = Highway Fuel Economy Test Cycle Requirement: Beginning SOC = Ending SOC Within a battery energy tolerance of 1% of cycle fuel energy

Step 1: Prep

Step 2: Urban Test 10min rest, key off

Step 3: Highway Test 15s rest, key stays on

12-36h rest U prep U U cold-start hot-start test test

Max 3h rest H prep H test

Weighted Urban Results = 0.43(cold-start) + 0.57(hot-start)

Components of a PHEV Test

1. Full Charge Test (FCT) - Start fully charged, repeat cycle until car
behaves like a charge-sustaining hybrid

2. Charge-Sustaining Test - Run test same as current charge-sustaining

hybrids (in sustaining mode)
(Full Charge)

until charge-sustaining

Full Charge Test (FCT)

Cycle 1 Cycle 2 Cycle 3 Cycle 4 Cycle n..

ChargeSustaining Test

Challenges: 1. Limitations of test cell hardware / software: 2. Vehicle initial conditions conflict with conventional vehicle procedures 3. Compatibility with existing test procedures, conditions, and calculations

J1711 Test Procedure Approach

Start

Default Test Method

Facility-Limited Method

Procedure
(limited number of options)

Option #1

Option #2

Option #1

Option #2

Calculations
(many viable options)

Option #3

Option #3

PHEV FCT Procedure for FTP

Test facility limitations require two test sequence choices.
Day Before Test
Prep
ch ar ge

12h to 36h

For Blended or AER Capable Vehicle

10min 10min 10min 10min 10min 10min 10min

Best interpretation of FCT, but may not be possible for many test facilities

Full

U
10min

U
10min

U
10min

U
10min

If above option is not possible, run this test

Full

20 To 30min

20 To 30min

20 To 30min

U Urban Dynamometer Drive Cycle (UDDS)

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PHEV Highway Cycle FCT Procedure

Again, facility limitations require two options.
Remember the Conventional HWY Test

Day Before Test Prep

ge

15s rest, key stays on

12h to 36h

ch ar

prep test

Prefer to run as many tests in a row as possible

Full

20 to 30 min

Full

Fall-Back Option (test cell limited)

20 To 30 min

20 To 30 min

H Highway Cycle
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Emissions Testing
J1711 to include emissions
emissions calculations same as fuel consumption purposes of inventory predictions or other needs

For emissions certification Up to EPA procedures, not in scope of J1711

worst case emissions, may be Depleting or Sustaining test results

OEMs demonstrate worst case

Utility Factor
Utility Factor is used to Calculate a Weighted Fuel Consumption that Corresponds to Distribution of National Daily Miles Driven

SAE J2841 Technical Information Report

Definition of the Utility Factor for Plug-In Hybrid Electric Vehicles Using US DOT National Household Travel Survey Data
100% 90% 80%

63% of drivers have charge depletion capable distance of 40 miles

Utility Factor [%]

70% 60% 50% 40% 30% 20% 10% 0% 0 10 20 30 40 50 60 70 80 90 100

Distance [miles]
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Testing PHEVs in the

Advanced Powertrain Research Facility at Argonne National Laboratory

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ANL PHEV Testing To Aid In J1711 Development

Prius Conversions 1. Hymotion (Kokam) Prius (highly instrumented) 2. HybridsPlus Prius (highly instrumented) 3. Hymotion (A123 ver.1) Prius (AVTA) 4. EnergyCS Prius ver.1 and ver.2 (AVTA) 5. Hymotion (A123 ver.2) Prius (owned by A123) Escape Conversions 6. Electrovaya Escape (AVTA / NYSERDA) 7. Hymotion Escape (AVTA / NYSERDA) 8. HybridsPlus Escape (AVTA / NYSERDA)Aug08 OEM 9. Renault Kangoo OEM PHEV Mule (NDA-protected) Extensive instrumentation/testing of OEM More OEM PHEVs Fall 2008 2

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Example PHEV Test Results

Hymotion Escape Electrovaya Escape

Supplemental battery 8kWh rated 6.2 kWh usable (from testing) A123 cells DC/DC converter supplements stock NiMH battery

Supplemental battery 12 kWh rated 5 kWh usable (from testing) Electrovaya cells Series Pass Regulator supplements stock NiMH battery

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Hymotion Escape and Electrovaya Escape have Different Rates of Depletion

Hymotion Escape MPG (during CD) = 56 AC Wh/mi (during CD) = 233 (Constant Rate of Depletion) 6.2 DCkWh used Petroleum Displacement = 46% Actual Depleting Range = 35mi

Electrovaya Escape MPG (during CD) = 43 AC Wh/mi (during CD) = 183 (Decreasing Rate of Depletion) 5 DCkWh used Petroleum Displacement= 34% Actual Depleting Range = 53 mi

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Energy Management - Depletion Rate: A Tradeoff Of Fuel And Electricity

Charge Sustaining (stock Escape)

Fa ste r

de ple

Electrovaya Escape
ti o n
Less efficient operation

Hymotion Escape
More efficient

Theoretical EV Wh/mi consumption

Any well-designed control strategy will roughly fall on line

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Entire Full Charge Test (FCT) Hymotion Escape

Charge-balance window Charge Sustaining

Transitional Cycle

Charge-Depleting

Cold-Start

Nearly Constant Depletion Rate

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Entire Full Charge Test (FCT) Electrovaya Escape

Charge-balance window Charge Sustaining Cold-Start

Decreasing Depletion Rate

Charge-Depleting

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Lets Explore PHEV MPG Ratings With Utility Factors

100%

Hymotion Escape
Max % VMT on Electricity

90% 80% 70% 60% 50% 40% 30% 20% 10% 0% 0 10 20 30 40 50 60 70 80 90 100

Electrovaya Escape
MPG (during CD) = 42.7 AC Wh/mi (CD) = 183 Depleting Range = 53 mi UF = 0.72 Bulk Method UF-Weighted MPG and Whr/mi = 39.4 MPG = 137 AC Whr/mi

MPG (during CD) = 56.3 AC Wh/mi (CD) = 233 Depleting Range = 35mi UF = 0.59 Bulk Method UF-Weighted MPG and Whr/mi = 44.1 MPG = 142 AC Whr/mi

PHEV Electric Range (Miles)

UF equation
Charge-depleting Charge-sustaining

1/ MPGUF = UF * (1/MPGCD ) + (1-UF) * 1/MPGCS

UF weighting makes it advantageous to deplete as quickly as possible

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Entire Full Charge Test (FCT) Hymotion Escape

Charge-balance window

Bulk Method UF Weighted Fuel Consumption and Electrical Energy Consumption

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Entire Full Charge Test (FCT) Electrovaya Escape

Charge-balance window

Bulk Method UF Weighted Fuel Consumption and Electrical Energy Consumption

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Piece-Wise Utility Factor Calculation

100%

Piece-Wise Calculation applies a UF to each cycle The minimum resolution is one cycle Transition cycle is consider to be part of the depletion operation This method is gaining acceptance and may prevail as the preferred method
UDDS Distance Cummulative [mi] UF 7.5 0.1770 15.0 0.3236 22.4 0.4404 29.9 0.5330 37.4 0.6059
1 MPG =
maxCD

90%

Max % VMT on Electricity

80% 70% 60% 50% 40% 30% 20% 10%

Cycle #1 Cycle #2 Cycle #3 Cycle #4 Cycle #5

Cycle UF 0.1770 0.1466 0.1167 0.0927 0.0729

0% 0 10 20 30 40 50 60 70 80 90 100

PHEV Electric Range (Miles)

ZEV

CDH

CS

UF (1/MPG
i
i=1

SOC
CD)i

(1- UFi )(1/ MPGCS)

i=1 maxCD

maxCD

AC Wh/mi =

UF (AC Wh/mi
i
i=1

CD)i

+ (1- UFi )(AC Wh/miCS)

i=1

Tests:

T1

T2

T3 T4 CD Cycles

T5

T6

T7 T8 CS Cycles
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Compare PHEV MPG Ratings With the Two UF Calculations

Hymotion Escape
MPG (during CD) = 56.3 AC Wh/mi (CD) = 233 Depleting Range = 35mi

Electrovaya Escape
MPG (during CD) = 42.7 AC Wh/mi (CD) = 183 Depleting Range = 53 mi

Bulk Method UF-Weighted

= 44.1 MPG = 142 AC Whr/mi

Bulk Method UF-Weighted

= 39.4 MPG = 137 AC Whr/mi

Piece-Wise UF-Weighted
= 44.1 MPG = 145 AC Whr/mi

Piece-Wise UF-Weighted
= 39.7 MPG = 149 AC Whr/mi

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Currently Addressing Final Challenges

Actual Charge-Depleting Range - Rcda "Electric Range Fraction Equations
SAE: ERF = 1- (FCcd / FCcs), FC=fuel consumption (units=?) CARB: ERF = (Mass CO2cs - Mass CO2cd) / Mass CO2cs, (units = grams)

"Full Charge Test (charge depleting) emissions compliance

Ywtd, g/mi = 0.43* Ycs/Dcs + 0.57* Sum of Yhs/Dhs results

Appropriate form of Voltage data for Net Energy Change calculation (NEC) HWY Cold-Start Correction Factor 1% of Fuel Energy Window for charge sustaining acceptance criterion. AC Charging Sensitivity Studies Sensitivity to Soak Time Between Tests in FCT

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Thank You

We would like to gratefully acknowledge the sponsorship of Pat Davis, Acting Program Manager and Lee Slezak, Manager, Advanced Vehicle Systems Simulation & Evaluation Team, Office of Vehicle Technologies Program, U.S, Department of Energy.

Vehicle Technologies Program

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Backup Slides

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Downloadable Dynamometer Database D3

A Website To Download APRF Test Data

https://webapps.anl.gov/vehicle_data
Easy search functions Basic operational data Comprehensive data available upon request More features, reports uploaded in future PHEVs and HEVs

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Utility Factor (UF) Explanation

Daily driving distances determine ratio of depleting to total miles US DOT National Highway Transportation Survey, 2001

50% depleting, 50% sustaining

Depleting miles
67% depleting, 33% sustaining
80

UF(40) = ---------------------30+40+50+60+80

30+40+40+40+40

80% depleting, 20% sustaining

60

= sustaining = depleting

100% depleting, 0% sustaining

50

Total miles

100% depleting, 0% sustaining

40 30

UF ( D ) =

d k R

min(d
d k R

, D)
distance driven on sample day

Depleting range = 40mi

k
Vehicle: 1 2 3 4 5

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SAE J1711

J1711

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How Many Depleting Miles Experienced by All is the Utility Factor

2001 NHTS Survey Data 84,916 vehicles 366,083 trips 3,297,712 miles

If vehicle has 40mi depleting range, 63% of all miles driven are in depleting mode
Area under line is UF fraction

40mi

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Defining a Plug-In HEV

ChargeDepleting
(start of day)

Historically, PHEVs were defined as EV capable until battery depleted, then conventional HEV operation.
PHEV20 20mi EV range PHEV60 60mi EV range

ChargeSustaining

SOC

EV Mode

Sustain Mode

x
miles EV range = Engine-on

Blended PHEVs do not require a full performance electric drive system. Engine operation needed during test cycle. But can deplete and displace a significant amount of fuel use.

(start of day)

ChargeDepleting

ChargeSustaining

SOC

Depleting Mode

x
miles CD range

Sustain Mode

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Summary of Electrified Vehicles

Vehicle Type Electric Power
Civic HEV

Electric Storage

Grid
Connected

Electric Driving

Mild HEV Full HEV

Conversion

Low Med Med Med+ High High

Low Low Med Med High High

No No Yes Yes Yes Yes

No Very limited Limited UDDS cycle Full

Performance

VUE HEV Prius HEV Escape HEV

Hymotion Prius

PHEV
AER- Capable

Toyota PHEV

PHEV
E-REV

GM Volt RAV-4 EV EV1

PHEV BEV

Full
Performance

AER = All Electric Range

Adapted from GM paper: The Electrification of the Automobile: From Conventional Hybrid, to Plug-in Hybrids, to Extended-Range Electric Vehicles, SAE 2008-01-0458

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PHEV Differentiated by Electric Power

E-REV
Wheel kW

Both AER-Capable
Urban-Capable

Blended

Wheel kW

04 Prius Max Acceleration

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Future of J1711
CARB PHEV Test Procedures and J1711 are linked CARB staff must present final rule in October to Board CARB will finish procedures this month As such, J1711 will also finish this summer J1711 Committee now addressing final 8 testing issues Data from OEMs will help in this last step EPA Label Fuel Economy still a difficult task not in scope of J1711

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