1. ACEA Comments from
ACEA welcomes the idea to develop a shortened range test procedure based on MCT
However, ACEA does not support JP proposal for SCT
But ACEA needs more time to elaborate on the JP MCT proposal
In addition, the proposed procedure is not totally clear, and ACEA would like to raise the following questions:
how long does CSCm lasts
would there be a benefit to start directly with CSCm as impact of first cycle is rather small (ca. 3%)?
why is the WLTC sequence extended with Middle and Low cycle; what does it mean “...to prevent uneven condition...?
what is the Break-off Criteria of the last CSCe?
how to test vehicles that have shorter ranges than the proposed MCT test (e.g. weighting of first phases will dominate)
how to test OVC HEV?
would there be a benefit to test at higher CSC speeds to further shorten the procedure

2. Validation of Shorten test procedure for BEV range
WLTP-DTP-E-Labproc082
prepared by Japan

3. Background
For EV range test of BEV and OVC-HEV, Japan recommend a single cycle test (SCT) method to represent real world vehicle performance in the WLTP process. On the other hands, it requires testing burdensome since WLTC consists of 4 (or 3) phases. To reduce testing burden maintaining representativeness for BEV, a multi cycle test (MCT) method which is based on SAE J1634 was evaluated for its applicability on WLTC.

4. Validation Tests with Multi Cycle Test Method
Test vehicle: Leaf (Nissan)
Test plan
(1)SCT (Single cycle test)
To conduct the range test for each phase.
(2)MCT (Multi cycle test)
To conduct MCT of WLTC
(set driving phase order taking into account of 4 phases)
(3) Compare SCT and MCT

5. Proposed shorten test procedure with MCT based on SAE J1634

6. Test vehicle Vehicle condition: 2011 Model(ZAA-ZE0)
Odometer : 4868 km (before the test)
Condition
4WD Chassis dynamometer
FF 2WD mode
Setting weight (for WLTP gtr condition)
1681kg
Ambient temperature ℃ 25

7. Measured Ranges with SCT
At this moment, only M & Ex-H analysis was completed. L&H analysis will be shown soon.
Test Results with SCT
Phase
Range
UBE
Usable Battery Capacity
Eac
Middle
170.1 km
19.7 kWh
24.3 kWh
Ex-High
98.5 km
19.5 kWh

8. Measured Discharge Energy with SCT(Middle)

9. Measured Energy Consumption with MCT
Phase
Distance km
Edc Wh
Discharge Energy
ECdc Wh/km
Energy Consumption
Low1
3.10
377
121.6
Middle1
4.75
632
133.2
High1
7.12
986
138.4
Ex-High1
8.25
1652
200.3
Middle2
542
114.0
Low2
335
108.2
CSCM
50.25
7537
150.0
Low3
3.09
108.6
Middle3
4.74
552
116.5
High2
7.11
970
136.4
Ex-High2
8.24
1651
Middle4
539
113.6
Low4
3.08
336
109.1
CSCE
24.26
3495
144.1
Usable Discharge Energy
19.9 kWh
Usable Discharge Energy is the summation of Edc.

10. Calculation equations for ranges with MCT
The range with MCT was estimated by the following equations.
Energy Consumption Wh/km = k1×EC1+ k2×EC2 + k3×EC3+ k4×EC4
Range km = (Usable Discharge Energy Wh) / (Energy Consumption Wh/km)
k1=(Discharge Energy for the first Cycle Wh) / (Usable Discharge Energy Wh)
k2= k3= k4 =(1- k1)/3
For middle range;
Energy Consumption Wh/km = k1×ECmiddle1+ k2×ECmiddle2 +
k3×ECmiddle3+ k4×ECmiddle4
= Wh/km
Where,
k1 = 632 Wh / 19.9 kWh = 0.03
k2 = k3 = k4 = (1- k1)/3 = 0.32
Range km =19.9 kWh/ Wh/km = km

11. Derived EV Range from MCT
Phase
Measured Range
(SCT)
Estimated Range
(MCT)
Comparison
SCT vs MCT
Low
Not yet
183.2km
To be confirmed
Middle
170.1km
172.9km
2.8km
1.7%
High
146.1km
Ex-High
98.5km
99.5km
1.0km
1.1%
It was observed that both range results are identical (few error). We still need to wait for other phase analysis, it has quite high possibility to apply MCT to WLTC
Time reduction effect with the shorten test procedure with MCT
　　The measurement of a single range for Middle with SCT consumed 5:40.
　　The measurement of four ranges with MCT consumed 3:30.

12. Conclusion
Japan recommend a SCT method for WLTC EV range test as primary procedure for representativeness.
It may have a good chance to apply the MCT method as an option to reduce testing burden.