**Draft**

**– Do not cite** 

**§1065.510 Engine mapping.** Modify the existing paragraph 1065.510(b) (5) (i) to better specify the setpoint speeds as follows: (b) Mapping variable

- speed engines. (5) Perform one of the following: (i) For any

engine subject only

to steady

- state duty

cycles (i.e., discrete

-mode or ramped

- modal), you may perform an engine map by using discrete speeds. Select map setpoint speeds based on the manufacturer declared maximum test speed as follows . From 95 % of warm idle speed to 90 % of the manufacturer declared maximum test speed, select at least 13 equally spaced setpoint speeds (i.e. a minimum of 12 equal speed intervals). From 90 % to 110 % of manufacturer declared maximum test speed select setpoint speeds in equal 2% increments (i.e. 92, 94, 96, ..., and 110 % of manufacturer declared maximum test speed). From 110 % of manufacturer declared maximum test speed to the highest speed above maximum power at which 50 % of maximum power occurs select setpoint speed s that are equal to the speed intervals determined for the portion of the map from 95 % warm idle speed to 90 % of manufacturer declared maximum test speed . We refer to this 50 % speed as the check point speed as described in paragraph (b)(5)(iii) of this section. If the manufacturer did not declared a maximum test speed, estimate the maximum test speed based on other manufacturer specifications; run the map using the setpoint speeds as described above; and verify that the measured maximum test speed falls on one of the discrete speeds from 92 to 108 % of the estimated maximum test speed. If the measured maximum test speed does not fall on one of these discrete speeds, rerun the map based on another estimate. At each setpoint, stabilize speed and al low torque to stabilize. Record the mean speed and torque at each setpoint. We recommend that you stabilize an engine for at least 15 seconds at each setpoint and record the mean feedback speed and torque of the last (4 to 6) seconds. Use linear interpolation to determine intermediate speeds and torques. Use this series of speeds and torques to generate the power map as described in paragraph (e) of this section. (ii) ... (iii) The check point speed of the map is the highest speed above maximum power at which 50 % of maximum power occurs. If this speed is unsafe or unachievable (e.g., for ungoverned engines or engines that do not operate at that point), use good engineering judgment to map up to the maximum safe speed or maximum achievable speed. For continuous mapping, if the engine cannot be mapped to the check point speed, verify that the sweep time from 95 % of warm idle to the maximum mapped speed is (4 to 6) min

. Insert a new paragraph 1065.510 ( g ) for the special case of electric hybrid engines. (g) Mapping variable speed engines with an electric hybrid systems . Map variable speed engines that include electric hybrid systems as described in this paragraph (g). Do not use this procedure for engines used in hy

brid vehicles where the hy brid system is certified as part of the vehicle rather than the engine. You may

ask to apply

these provisions to other ty pes of hybrid engines, consistent with good engineering judgment. Follow the steps for mapping a variable

- speed engine as given in paragraph (b) of this section with the exceptions noted in this paragraph (g) . Note that you are generally required to generate two separate engine maps: one with the hybrid system active, and one with it inactive. The map with the system inactive is used to generate steady

- state duty cycles and transient cycles that specifies no negative torques (i.e. no engine motoring)

. This map is also used in generating the map with the system active. The map with the system active is used to generate transient duty cycles that specify negative torques (i.e. engine motoring)

. If your engine is subject toa reference duty cycle that specifies negative normalized torques (i.e. engine motoring), you may

skip the generation of a motoring map as described in paragraph (c) of this section and exclude motoring points from the cycle regression. Apply the provisions of paragraph (b) of this section with the following exceptions : (1) This paragraph (g)(1) specifies exceptions when generating a map with the hybrid system inactive. Operate the engine as specified in paragraph (b)(4) o f this section , but remain at this condition until the renewable energy storage system (RESS) is depleted. Once the RESS is depleted, perform an engine map as specified in paragraph (b)(5) of this section. Ensure that instantaneous power from the RESS remains less than 2 % of the instantaneous measured power from the system at all system speeds. (2) This paragraph (g)(2) specifies exceptions when generating a map with the hy brid system active

. You may us e a nominally continuous method or a discrete method. You may use either of the following methods to generate a map with the hybrid system active: (i) You may

perform an engine map by using a series of continuous sweeps of narrow speed ranges. Note that the purpose of this mapping approach is to determine the maximum torque available at each speed such as might occur during transient operation with a fully charged RESS. Begin by fully charging the RESS. Perform the sweep as specified in paragraph (b)(5) (ii) of this section, but stop the ramp to charge the RESS when the power measured from the RESS drops below maximum expected RESS power by more than 2% of total system power (including engine and RESS power). Unle ss good engineering judgment indicates otherwise, use a linear fit for RESS power during the first 3 seconds of each sweep to predict the maximum expected RESS power during the remainder of th at sweep Calculate total system power as a 3 second moving average of the as - measured instantaneous total system power. For example, if the 3 second moving average of total engine

- RESS power is 200 kW and the power from the RESS at the beginning of the ramp is 50 kW, once the power from the RESS reaches 46 kW, stop the ramp to charge the RESS . After each charging event, stabilize the engine for 15 seconds at the speed at which you ended the previous segment with operator demand set to maximum before continuing the ramp from that speed. Repeat the cycle of charging, mapping, and recharging until you have completed the engine map. You may shutdown the system or include other operation between segments to be consistent with the intent of this paragraph(g)(2)(i). For example, for systems in which continuous charging and discharging can overheat batteries to an extent that affects performance , you may operate the engine at zero power from the RESS for enough time after the system is recharged to allow the batteries to cool. Use good engineering judgment to smooth the torque curve to eliminate discontinuities between map intervals. (For example , for each sweep interval, smooth torque data using a speed

- scaled method) (ii) You may

perform an engine map by using discrete speeds. Select map setpoint speeds as described in paragraph (b)(5)(i) of this section. At each setpoint speed , stabilize speed and target torque at about 70 % of peak torque of the non

- hybrid assisted engine. Make sure the engine is fully warmed up and the RESS state of charge is within the normal operating range. Snap the throttle to maximum andrecord at 1 Hz or higher the 3

- second moving average values of the continuous feedback speed and torque signals

. Continue to re c ord for 30 s or until the 3

- second moving average torque peaks and begins to fall. From data recorded during this snap throttle maneuver, identify the maximum 3

- second average torque . Use this torque value and the corresponding 3

- second moving average speed (i.e. the 3

- second average speed recorded at the same time where the 3

- second average torque was at its maximum) as the speed and torque for the map at this discrete speed point

. Repeat this maneuver for each discrete speed

.