Innovative technology
The technology used in a 48 Volt efficient motor-generator combined with a 48 Volt/12 Volt DC/DC converter is approved as an innovative technology within the meaning of Article 11 of Regulation (EU) 2019/631 taking into account that the CO 2 savings it delivers are only partially covered by the standard test procedure set out in Regulation (EU) 2017/1151, and provided that the technology conforms to the following:
(a)
it is fitted in passenger cars (M 1 ) or light commercial vehicles (N 1 ) powered by internal combustion engines running on petrol or diesel (conventional ICE powered M 1 and N 1 vehicles) or in not-off-vehicle charging hybrid electric vehicles of category M 1 or N 1 for which uncorrected measured fuel consumption and CO 2 emission values may be used in accordance with paragraph 1.1.4 of Appendix 2, Sub-annex 8 to Annex XXI to Regulation (EU) 2017/1151;
(b)
its efficiency, which is the product of the efficiency of the 48 Volt motor-generator and the efficiency of the 48 Volt/12 Volt DC/DC converter, determined in accordance with point 2.3 of the Annex, is at least
(i)
73,8 % for petrol-fuelled vehicles other than turbo-charged;
(ii)
73,4 % for turbo-charged petrol-fuelled vehicles;
(iii)
74,2 % for diesel-fuelled vehicles.
Application for certification of CO 2 savings
1. A manufacturer may apply to a type-approval authority for certification of the CO 2 savings from the use of the technology approved in accordance with Article 1 (‘the innovative technology’) by reference to this Decision.
2. The manufacturer shall ensure that the application for the certification is accompanied by a verification report from an independent and certified body confirming that the technology conforms to points (a) and (b) of Article 1.
3. Where CO 2 savings have been certified in accordance with Article 3, the manufacturer shall ensure that the certified CO 2 savings and the eco-innovation code referred to in Article 4(1) are recorded in the certificate of conformity of the vehicles concerned.
Certification of CO 2 savings
1. The type-approval authority shall ensure that CO 2 savings achieved from the use of the innovative technology have been determined using the methodology set out in the Annex.
2. Where a manufacturer applies for the certification of the CO 2 savings for more than one type of 48 Volt motor-generator combined with a 48 Volt/12 Volt DC/DC converter in relation to one vehicle version, the type-approval authority shall determine which of the 48 Volt motor-generators combined with a 48 Volt/12 Volt DC/DC converter tested delivers the lowest CO 2 savings. That value shall be used for the purpose of paragraph 4.
3. The type approval authority shall record the certified CO 2 savings calculated in accordance with point 4 of the Annex, and the eco-innovation code referred to in Article 4(1) in the relevant type-approval documentation.
4. The type-approval authority shall record all the elements considered for the certification in a test report and keep that together with the verification report referred to in Article 2(2), and shall make that information available to the Commission on request.
5. The type-approval authority shall only certify CO 2 savings from the use of the innovative technology if it finds that the technology conforms with points (a) and (b) of Article 1, and if the CO 2 savings determined in accordance with point 3.5 of the Annex are 0,5 g CO 2 /km or higher, as specified in Article 9(1)(b) of Implementing Regulation (EU) No 725/2011 in the case of passenger cars, or in Article 9(1)(b) of Implementing Regulation (EU) No 427/2014 in the case of light commercial vehicles.
Eco-innovation code
1. The innovative technology approved by this Decision is attributed with the eco-innovation code 32.
2. The certified CO 2 savings recorded by reference to that eco-innovation code may be taken into account for the calculation of the average specific emissions of manufacturers starting from the calendar year 2021.
Entry into force
This Decision shall enter into force on the twentieth day following that of its publication in the Official Journal of the European Union .
Methodology to determine the CO 2 savings of the technology used in a 48 Volt efficient motor-generator combined with a 48 Volt/12 Volt DC/DC converter for conventional combustion engine and certain hybrid electric passenger cars and light commercial vehicles
ANNEXSupplementary provisions
ANNEX
Methodology to determine the CO 2 savings of the technology used in a 48 Volt efficient motor-generator combined with a 48 Volt/12 Volt DC/DC converter for conventional combustion engine and certain hybrid electric passenger cars and light commercial vehicles
1. INTRODUCTION
This Annex sets out the methodology to determine the CO 2 (carbon dioxide) emission savings from the use of a 48 Volt efficient motor-generator (‘48V motor-generator’), combined with a 48 Volt/12 Volt DC/DC converter ‘48V/12V DC/DC converter’), in an M 1 or N 1 vehicle as specified in Article 1(a)).
2. DETERMINATION OF THE EFFICIENCIES
The efficiency of the 48V motor-generator and the 48V/12V DC/DC converter is to be determined separately as specified in points 2.1 and 2.2. The resulting values are to be used as input for the calculation of the total efficiency of the 48V motor-generator combined with the 48V/12V DC/DC converter in accordance with point 2.3.
2.1. 48V motor-generator efficiency
The efficiency of the 48V motor-generator shall be determined in accordance with ISO 8854:2012, with the following precisions.
The manufacturer shall provide evidence to the type-approval authority that the frequency ranges of the 48V motor-generator are the same as or equivalent to those set out in Table 1.
The efficiency of the 48V motor-generator shall be determined on the basis of measurements at each of the operating points listed in Table 1.
The current intensity of the 48V motor-generator at each operating point shall be half the rated current. For each operating point, the voltage and the output current of the 48V motor-generator shall be kept constant during the measurement, with the voltage at 52V.
Table 1
Operating point
i
Holding time
[s]
Rotational frequency
Frequency of operating points
1
1 200
1 800
0,25
2
1 200
3 000
0,40
3
600
6 000
0,25
4
300
10 000
0,10
The efficiency of the 48V motor-generator at each operating point i (
) [%] shall be calculated in accordance with Formula 1.
Formula 1
where, for each operating point i,
U i
is the voltage [V];
I i
is the current intensity [A];
Μ i
is the torque [Nm];
n i
is the rotational frequency [min -1 ].
For each operating point, the measurements are to be performed at least five times consecutively and the efficiency shall be calculated for each of those measurements
with j being the index referring to one set of measurements.
For each operating point, the average of those efficiencies
shall be calculated.
The efficiency of the 48V motor-generator
[%] shall be calculated in accordance with Formula 2.
Formula 2
where
is the mean efficiency of the 48V motor-generator determined for operating point i [%]
h i
is the frequency of operating point i, as set out in Table 1.
2.2. 48V/12V DC/DC converter efficiency
The efficiency of the 48V/12V DC/DC converter shall be determined under the following conditions:
—
Input voltage of 52 V
—
Output voltage of 14,3 V
—
Output current: nominal power of the 48V/12V DC/DC converter divided by the output voltage of 14,3 V
The nominal power of the 48V/12V DC/DC converter shall be the continuous output power certified by the supplier in accordance with the requirements specified in ISO 8854:2012.
The efficiency of the 48V/12V DC/DC converter
[%] shall be calculated from the current and voltage intensity measurements according to Formula 3.
Formula 3
where
is the input voltage, which shall be set to 52 [V]
is the current intensity measured on the input side [A]
is the output voltage, which shall be set to 14,3 [V]
is the current intensity measured on the output side, which should be equal to the nominal power of the 48V/12V DC/DC converter divided by the output voltage [A]
The measurements and efficiency calculations shall be repeated at least five (5) times consecutively.
The average of those efficiencies shall then be the efficiency of the 48V/12V DC/DC converter
[%].
2.3. Combined efficiency
The efficiency of the 48V motor generator combined with the 48V/12V DC/DC converter
[%] is calculated in accordance with Formula 4.
Formula 4
:
is the efficiency of the 48V motor-generator, as determined in point 2.1 [%]
is the efficiency of the 48V/12V DC/DC converter, as determined in point 2.2 [%]
3. CALCULATION OF THE CO 2 SAVINGS
3.1. Saved mechanical power
The difference
[W] between the saved mechanical power when using the 48V motor generator combined with the 48V/12V DC/DC converter under real-world conditions
and the saved mechanical power when using the 48V motor generator combined with the 48V/12V DC/DC converter under type-approval conditions
shall be calculated in accordance with Formula 5.
Formula 5
where
shall be calculated in accordance with Formula 6 and
in accordance with Formula 7.
Formula 6
Formula 7
where,
is the efficiency of the 48V motor-generator combined with the 48V/12V DC/DC converter, as determined in point 2.3 [%]
is the power requirement under ‘real-world’ conditions, which is 750 W
is the power requirement under ‘type-approval’ conditions, which is 350 W
is the efficiency of the baseline alternator, which is 67 %
3.2. Calculation of the CO 2 savings
The CO 2 savings of the 48V motor-generator combined with the 48V/12V DC/DC converter
shall be calculated in accordance with Formula 8.
Formula 8
where,
is the difference between the saved mechanical power under real-world conditions and the saved mechanical power under type-approval conditions, as determined in point 3.1
is the mean driving speed of the WLTP, which is 46,6 km/h
is the consumption of effective power as specified in Table 2 [l/kWh]
CF
is the conversion factor as set out in Table 3
Table 2
Type of engine
Consumption of effective power
Petrol-fuelled other than turbo-charged
0,264
Turbo-charged petrol-fuelled
0,280
Diesel-fuelled
0,220
Table 3
Type of fuel
Conversion factor (CF)
Petrol
2 330
Diesel
2 640
3.3. Calculation of the uncertainty of the CO 2 savings
The uncertainty of the CO 2 savings calculated in accordance with point 3.2 shall be quantified.
For this, the following calculations are needed.
First, the standard deviation of the efficiency of the 48V motor-generator at each operating point
[%] shall be calculated in accordance with Formula 9.
Formula 9
where
is the number of measurements j undertaken at each operating point i for the 48V motor-generator efficiency, as referred to in point 2.1
is the efficiency of the 48V motor-generator calculated for an individual measurement j at operating point i as referred to in point 2.1 [%]
is the average efficiency of the 48V motor-generator calculated for an operating point i, as determined in point 2.1 [%]
Next, the standard deviation of the efficiency of the 48V motor-generator
[%] shall be calculated in accordance with Formula 10.
Formula 10
where
is as determined by Formula 9 [%]
h i
is the frequency of operating point i, as set out in Table 1.
Then, the standard deviation of the efficiency of the 48V/12V DC/DC converter
[%] shall be calculated in accordance with Formula 11.
Formula 11
where
L
is the number of measurements l undertaken for the 48V/12V DC/DC converter, as referred to in point 2.2
is the efficiency of the 48V/12V DC/DC converter calculated for an individual measurement l as referred to in point 2.2 [%]
is the efficiency of the 48V/12V DC/DC converter, as determined in point 2.2 [%]
Finally, the uncertainty in the CO 2 savings
of the 48V motor-generator combined with the 48V/12V DC/DC converter shall be calculated in accordance with Formula 12 and shall not exceed 30 % of the CO 2 savings.
Formula 12
where
is the power requirement under ‘real-world’ conditions, which is 750 W
is the power requirement under type-approval conditions, which is 350 W
is the total efficiency of the 48V motor-generator combined with the 48V/12V DC/DC converter as determined in point 2.3 [%]
is the consumption of effective power as specified in Table 2 [l/kWh]
is the fuel conversion factor as specified in Table 3
is the mean driving speed of the WLTP, which is 46,6 km/h
is standard deviation of the efficiency of the 48V motor-generator as determined in accordance with Formula 10 [%]
is the efficiency of the 48V motor-generator, as determined in point 2.1 [%]
is the standard deviation of the efficiency of the 48V/12V DC/DC converter, as determined in accordance with Formula 11 [%]
is the efficiency of the 48V/12V DC/DC converter as determined in point 2.2 [%]
3.4. Rounding
The CO 2 savings
calculated in accordance with point 3.2 and the uncertainty of the CO 2 savings
calculated in accordance with point 3.3 shall be rounded to a maximum of two decimal places.
Each value used in the calculation of the CO 2 savings can be applied unrounded or must be rounded to the minimum number of decimal places which allows the maximum total impact (i.e. combined impact of all rounded values) on the savings to be lower than 0,25 gCO 2 /km.
3.5. Check against the minimum CO 2 savings threshold
The type-approval authority shall ensure for each vehicle version fitted with the 48V motor-generator combined with the 48V/12V DC/DC converter that the minimum threshold criterion as specified in Article 9(1)(b) of Implementing Regulation (EU) No 725/2011 and Implementing Regulation (EU) No 427/2014 is met.
When verifying whether the minimum threshold criterion is met, the type-approval authority shall take into account, in accordance with Formula 13, the CO 2 savings determined in point 3.2, the uncertainty determined in point 3.3 and, where applicable, a CO 2 correction, in the case of a positive mass difference (Δm) between the 48V motor-generator combined with the 48V/12V DC/DC converter and the baseline alternator.
For the purpose of the positive mass correction, the mass of the baseline alternator shall be set to 7 kg.
The manufacturer shall provide to the type approval authority information on the mass of the 48V motor-generator combined with the 48V/12V DC/DC converter as certified by the supplier.
Formula 13
where,
MT
is 0,5 g CO 2 /km as specified in Article 9(1)(b) of Implementing Regulation (EU) No 725/2011 and Commission Implementing Regulation (EU) No 427/2014
is the CO 2 savings as determined in point 3.2
uncertainty of the total CO 2 savings as determined in point 3.3
CO 2 correction, in the case of a positive mass difference (Δm) [kg] between the 48V motor-generator combined with the 48V/12V DC/DC converter and the baseline alternator, calculated in accordance with Table 4:
Table 4
Type of fuel
CO 2 correction
Petrol
0,0277 Δm
Diesel
0,0383 Δm
4. CERTIFICATION OF CO 2 SAVINGS
The CO 2 savings to be certified by the type-approval authority in accordance with Article 11 of Implementing Regulations (EU) No 725/2011 or (EU) No 427/2014
are those calculated in accordance with Formula 14. The CO 2 savings shall be recorded in the type approval certificate for each vehicle version fitted with the 48V motor-generator combined with the 48V/12V DC/DC converter.
Formula 14
where,
is the CO 2 savings as determined in accordance with Formula 8 under point 3.2
is the uncertainty in the CO 2 savings of the 48V motor-generator combined with the 48V/12V DC/DC converter calculated in accordance with Formula 12 under point 3.3
