Commission Regulation (EU) 2017/1151Show full title

[F1 Sub-Annex 6 - Appendix 2

Test procedure for rechargeable electric energy storage system monitoring U.K.

1. General U.K.

In the case that NOVC-HEVs and OVC-HEVs are tested, Appendices 2 and 3 to Sub-Annex 8 shall apply.

This Appendix defines the specific provisions regarding the correction of test results for CO ₂ mass emission as a function of the energy balance ΔE _REESS for all REESSs.

The corrected values for CO ₂ mass emission shall correspond to a zero energy balance (ΔE _REESS = 0), and shall be calculated using a correction coefficient determined as defined below.

2. Measurement equipment and instrumentation U.K.

2.1. Current measurement U.K.

REESS depletion shall be defined as negative current.

2.1.1. The REESS current(s) shall be measured during the tests using a clamp-on or closed type current transducer. The current measurement system shall fulfil the requirements specified in Table A8/1. The current transducer(s) shall be capable of handling the peak currents at engine starts and temperature conditions at the point of measurement. U.K.

In order to have an accurate measurement, zero adjustment and degaussing shall be performed before the test in accordance with the instrument manufacturer's instructions.

2.1.2. Current transducers shall be fitted to any of the REESS on one of the cables connected directly to the REESS and shall include the total REESS current. U.K.

In case of shielded wires, appropriate methods shall be applied in accordance with the approval authority.

In order to easily measure REESS current using external measuring equipment, manufacturers should preferably integrate appropriate, safe and accessible connection points in the vehicle. If this is not feasible, the manufacturer shall support the approval authority by providing the means to connect a current transducer to the REESS cables in the manner described above.

2.1.3. The measured current shall be integrated over time at a minimum frequency of 20 Hz, yielding the measured value of Q, expressed in ampere-hours Ah. The measured current shall be integrated over time, yielding the measured value of Q, expressed in ampere-hours Ah. The integration may be done in the current measurement system. U.K.

2.2. Vehicle on-board data U.K.

2.2.1. Alternatively, the REESS current shall be determined using vehicle-based data. In order to use this measurement method, the following information shall be accessible from the test vehicle: U.K.

(a)

Integrated charging balance value since last ignition run in Ah;

(b)

Integrated on-board data charging balance value calculated at a minimum sample frequency of 5 Hz;

(c)

The charging balance value via an OBD connector as described in SAE J1962.

2.2.2. The accuracy of the vehicle on-board REESS charging and discharging data shall be demonstrated by the manufacturer to the approval authority. U.K.

The manufacturer may create a REESS monitoring vehicle family to prove that the vehicle on-board REESS charging and discharging data are correct. The accuracy of the data shall be demonstrated on a representative vehicle.

The following family criteria shall be valid:

(a)

Identical combustion processes (i.e. positive ignition, compression ignition, two-stroke, four-stroke);

(b)

Identical charge and/or recuperation strategy (software REESS data module);

(c)

On-board data availability;

(d)

Identical charging balance measured by REESS data module;

(e)

Identical on-board charging balance simulation.

2.2.3. All REESS having no influence on CO ₂ mass emissions shall be excluded from monitoring. U.K.

3. REESS energy change-based correction procedure U.K.

3.1. Measurement of the REESS current shall start at the same time as the test starts and shall end immediately after the vehicle has driven the complete driving cycle. U.K.

3.2. The electricity balance Q measured in the electric power supply system, shall be used as a measure of the difference in the REESS energy content at the end of the cycle compared to the beginning of the cycle. The electricity balance shall be determined for the total driven WLTC. U.K.

3.3. Separate values of Q _phase shall be logged over the driven cycle phases. U.K.

3.4. Correction of CO ₂ mass emission over the whole cycle as a function of the correction criterion c U.K.

3.4.1. Calculation of the correction criterion c U.K.

The correction criterion c is the ratio between the absolute value of the electric energy change ΔE _REESS,j and the fuel energy and shall be calculated using the following equations:

where:

c

is the correction criterion;

ΔE _REESS,j

is the electric energy change of all REESSs over period j determined in accordance with paragraph 4.1. of this Appendix, Wh;

j

is, in this paragraph, the whole applicable WLTP test cycle;

E _Fuel

is the fuel energy calculated with the following equation:

E _fuel = 10 × HV × FC _nb × d

where:

E _fuel

is the energy content of the consumed fuel over the applicable WLTP test cycle, Wh;

HV

is the heating value in accordance with Table A6.App2/1, kWh/l;

FC _nb

is the non-balanced fuel consumption of the Type 1 test, not corrected for the energy balance, determined in accordance with paragraph 6. of Sub-Annex 7, and using the results for criteria emissions and CO ₂ calculated in Step 2 in Table A7/1, l/100 km;

d

is the distance driven over the corresponding applicable WLTP test cycle, km;

10

conversion factor to Wh.

3.4.2. The correction shall be applied if ΔE _REESS is negative (corresponding to REESS discharging) and the correction criterion ‘c’ calculated in accordance with paragraph 3.4.1. of this Appendix is greater than the applicable threshold in accordance with Table A6.App2/2. U.K.

3.4.3. The correction shall be omitted and uncorrected values shall be used if the correction criterion ‘ c ’ calculated in accordance with paragraph 3.4.1. of this Appendix is less than the applicable threshold in accordance with Table A6.App2/2. U.K.

3.4.4. The correction may be omitted and uncorrected values may be used if: U.K.

(a)

ΔE _REESS is positive (corresponding to REESS charging) and the correction criterion ‘c’ calculated in accordance with paragraph 3.4.1. of this Appendix is greater than the applicable threshold in accordance with Table A6.App2/2;

(b)

the manufacturer can prove to the approval authority by measurement that there is no relation between ΔE _REESS and CO ₂ mass emission and ΔE _REESS and fuel consumption respectively.

Table A6.App2/1

Energy content of fuel

Fuel	Petrol							Diesel
Content Ethanol/Biodiesel, per cent			E10			E85				B7
Heat value (kWh/l)			8,64			6,41				9,79

Table A6.App2/2

RCB correction criteria thresholds

Cycle	low + medium)	low + medium + high	low + medium + high + extra high
Thresholds for correction criterion c	0,015	0,01	0,005

4. Applying the correction function U.K.

4.1. To apply the correction function, the electric energy change ΔT _REESS,j of a period j of all REESSs shall be calculated from the measured current and the nominal voltage: U.K.

where:

ΔE _REESS,j,i

is the electric energy change of REESS i during the considered period j, Wh;

and:

where:

U _REESS

is the nominal REESS voltage determined in accordance with IEC 60050-482, V;

I(t) _j,i

is the electric current of REESS i during the considered period j, determined in accordance with paragraph 2. of this Appendix, A;

t ₀

is the time at the beginning of the considered period j, s;

t _end

is the time at the end of the considered period j, s.

i

is the index number of the considered REESS;

n

is the total amount of REESS;

j

is the index number for the considered period, where a period shall be any applicable cycle phase, combination of cycle phases and the applicable total cycle;

is the conversion factor from Ws to Wh.

4.2. For correction of CO ₂ mass emission, g/km, combustion process-specific Willans factors from Table A6.App2/3 shall be used. U.K.

4.3. The correction shall be performed and applied for the total cycle and for each of its cycle phases separately, and shall be included in all relevant test reports. U.K.

4.4. For this specific calculation, a fixed electric power supply system alternator efficiency shall be used: U.K.

η _alternator = 0,67 for electric power supply system REESS alternators

4.5. The resulting CO ₂ mass emission difference for the considered period j due to load behaviour of the alternator for charging a REESS shall be calculated using the following equation: U.K.

where:

ΔM _CO2,j

is the resulting CO ₂ mass emission difference of period j, g/km;

ΔE _REESS,j

is the REESS energy change of the considered period j calculated in accordance with paragraph 4.1. of this Appendix, Wh;

d _j

is the driven distance of the considered period j, km;

j

is the index number for the considered period, where a period shall be any applicable cycle phase, combination of cycle phases and the applicable total cycle;

0,0036

is the conversion factor from Wh to MJ;

η _alternator

is the efficiency of the alternator in accordance with paragraph 4.4. of this Appendix;

Willans _factor

is the combustion process-specific Willans factor as defined in Table A6.App2/3, gCO ₂ /MJ;

4.5.1. The CO ₂ values of each phase and the total cycle shall be corrected as follows: U.K.

M _CO2,p,3 = M _CO2,p,1 – ΔM _CO2,j

M _CO2,c,3 = M _CO2,c,2 – ΔM _CO2,j

where:

ΔM _CO2,j

is the result from paragraph 4.5. of this Appendix for a period j, g/km.

4.6. For the correction of CO ₂ emission, g/km, the Willans factors in Table A6.App2/3 shall be used. U.K.

Table A6.App2/3

Willans factors

			Naturally aspirated	Pressure-charged
Positive ignition
	Petrol (E10)	l/MJ	0,0756	0,0803
		gCO 2 /MJ	174	184
	CNG (G20)	m 3 /MJ	0,0719	0,0764
		gCO 2 /MJ	129	137
	LPG	l/MJ	0,0950	0,101
		gCO 2 /MJ	155	164
	E85	l/MJ	0,102	0,108
		gCO 2 /MJ	169	179
Compression ignition
	Diesel (B7)	l/MJ	0,0611	0,0611
		gCO 2 /MJ	161	161]

Textual Amendments

F1 Substituted by Commission Regulation (EU) 2018/1832 of 5 November 2018 amending Directive 2007/46/EC of the European Parliament and of the Council, Commission Regulation (EC) No 692/2008 and Commission Regulation (EU) 2017/1151 for the purpose of improving the emission type approval tests and procedures for light passenger and commercial vehicles, including those for in-service conformity and real-driving emissions and introducing devices for monitoring the consumption of fuel and electric energy (Text with EEA relevance).