Difference between revisions of "Lambda drivers (LAMFAW)"
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− | '' | + | See the ''funktionsrahmen ''for the following diagrams: |
− | LAMFAW | + | |
− | + | lamfaw-lamfaw | |
− | + | ||
− | + | lamfaw-lamkr | |
− | + | ||
− | + | lamfaw-lamwl | |
− | + | ||
+ | lamfaw-lamfadisable | ||
+ | |||
+ | lamfaw-lamrlmin | ||
+ | |||
+ | lamfaw-initialise | ||
+ | |||
+ | <u>Function Description</u> | ||
+ | |||
+ | |||
+ | The function LAMFAW brings about an enrichment of the fuel-air mixture via lamfa_w when the driver demands maximum torque via mrfa_w. This then corresponds to the full-load enrichment. The intervention to the mixture via lamfa_w can be delayed via the delay time TLAFA. During turbocharger overboost, an additional enrichment is applied by a delta-lambda from the characteristic DLAMOB. | ||
+ | |||
+ | |||
+ | For the time TLAMFAS, an enrichment via the driver’s request as a function of altitude (LAMFAS) can be prevented (see sub-function LAMFADISABLE). Triggering of this time will be initiated if B_kh = true, LAMFA <1.0 and the altitude at which the function is disabled (as defined in LAMFAS) has been reached. | ||
+ | |||
+ | |||
+ | In this way, a reproducible driving cycle can also be achieved at higher altitudes. | ||
+ | |||
+ | |||
+ | During a torque reduction, e.g. traction control intervention, engine speed limiter …, the enrichment via the map LAMFAW can be disabled by setting CWMFAW Bit 1 = true. | ||
+ | |||
+ | |||
+ | In the sub-function LAMKR, an enrichment can be implemented during ignition angle intervention. | ||
+ | |||
+ | The sub-function LAMWL can be used for the enrichment during warm-up. If this procedure is used, tank-venting via the function LAMKO is not switched off. | ||
+ | |||
+ | |||
+ | In the sub-function LAMRLMIN, an enrichment via LAMRLMN is active for low loads (rl). This improves the combustion efficiency at low loads. If CWLAMFAW bit 2 is set, then the emergency fuel tank breather is disabled during lamrlmn-intervention. | ||
+ | |||
+ | |||
+ | <u>Application Notes</u> | ||
+ | |||
+ | |||
+ | A delay time TLAFA > 0 can only be applied when the mixture intervention via lamfa_w should be delayed. | ||
+ | |||
+ | |||
+ | Map LAMFA: | ||
+ | |||
+ | |||
+ | Engine speed sample points: 1000, 1400, 1800, 2200, 2600, 3000, 3400, 3800, 4200, 4600, 5000, 5400, 5800, 6200, 6600, 7000 rpm | ||
+ | |||
+ | mrfa_w sample points: 70, 80, 90, 100, 110, 120 % | ||
+ | |||
+ | Map values of 1.0 | ||
+ | |||
+ | |||
+ | DLAMOB comprises the delta-lambda, so that an additional mixture enrichment is implemented in overboost mode. | ||
+ | |||
+ | Sample points for engine speed: implemented as a group characteristic SNM06GKUB | ||
+ | |||
+ | Neutralization of the function by data: | ||
+ | |||
+ | LAMFA = 1.0 and DLAMOB = 0.0 ® lamfa_w is then 1.0 | ||
+ | |||
+ | The time TLAMFAS must be selected so that no large gradients are caused in the driver’s requested enrichment (typically 240 s). | ||
+ | |||
+ | |||
+ | The characteristic LAMFAS contains values ​​from 0 to 1. If the value is 0, enrichment via the altitude effect is active. Values ​​other than 0 deactivate enrichment via LAMFA, if B_kh = true and LAMFA values ​​are < 1.0. | ||
+ | |||
+ | |||
+ | The characteristic LAMFAS is not interpolated, which means that the characteristic initial value remains constant until a node is crossed. | ||
+ | |||
+ | |||
+ | For the fho-sample points of the characteristic LAMFAS, the following relationship applies: fho = 1 | ||
+ | – altitude [m]/10,000 m | ||
+ | |||
+ | |||
+ | Since the variable fho has a quantization of 4/256 = 0.015625, this resolution must be considered when determining the switch-off. Similarly, there is a potential altitude deviation of ± 250 m because of the sensor tolerance. | ||
+ | |||
+ | |||
+ | For the calculation of the lower or upper threshold of fho, the following relationship applies for a nominal altitude cut-off threshold: | ||
+ | |||
+ | |||
+ | <u>Lower altitude cut-off threshold:</u> | ||
+ | |||
+ | |||
+ | fho [phys] = 1 – ((nominal altitude [m] – 250 m ) /10000) ® fho[Ink] = Integer (fho[phys]/0.015625) + 1Ink | ||
+ | |||
+ | |||
+ | ® fho upper limit [phys] = (1 – fho[Ink] x 0.015625) | ||
+ | |||
+ | |||
+ | ® Altitude upper limit = (1 – fho upper limit [phys]) x 10000 | ||
+ | |||
+ | |||
+ | <u>Upper altitude cut-off threshold:</u> | ||
+ | |||
+ | |||
+ | fho [phys] = 1 – ((nominal altitude [m] + 250 m) /10000) | ||
+ | |||
+ | ® fho[Ink] = Integer (fho[phys] /0.015625) | ||
+ | |||
+ | |||
+ | ® fho lower limit [phys] = fho[Ink] x 0.015625 | ||
+ | |||
+ | |||
+ | ® Altitude lower limit = (1 – fho lower limit [phys]) ´ 10000 | ||
+ | |||
+ | |||
+ | This produces the following values: | ||
+ | |||
+ | |||
+ | {| border="1" | ||
|- | |- | ||
− | | | + | | |
+ | Nominal | ||
+ | altitude | ||
+ | | | ||
+ | 2,200 m | ||
+ | | | ||
+ | 1,600 m | ||
+ | | | ||
|- | |- | ||
− | | | + | | |
+ | Altitude | ||
+ | upper limit | ||
+ | | | ||
+ | 2,500 m | ||
+ | | | ||
+ | 1,875 m | ||
+ | | | ||
+ | The altitude upper limit is the fho lower limit! | ||
|- | |- | ||
− | | | + | | |
+ | fho lower limit | ||
+ | | | ||
+ | 0.75 | ||
+ | | | ||
+ | 0.8125 | ||
|- | |- | ||
− | | | + | | |
+ | Altitude lower limit | ||
+ | | | ||
+ | 1,875 m | ||
+ | | | ||
+ | 1,250 m | ||
+ | | | ||
|- | |- | ||
− | | | + | | |
+ | fho upper limit | ||
+ | | | ||
+ | 0.8125 | ||
+ | | | ||
+ | 0.875 | ||
+ | | | ||
+ | |} | ||
+ | |||
+ | |||
+ | Thus, the characteristic LAMFAS is parameterized as follows for the nominal altitude of | ||
+ | 2,200 m: | ||
+ | |||
+ | |||
+ | {| border="1" | ||
|- | |- | ||
− | | | + | | |
+ | fho | ||
+ | | | ||
+ | 0.734375 | ||
+ | | | ||
+ | 0.7500 | ||
+ | | | ||
+ | 0.8125 | ||
|- | |- | ||
− | | | + | | |
+ | Value | ||
+ | | | ||
+ | 0 | ||
+ | | | ||
+ | 1 | ||
+ | | | ||
+ | 0 | ||
|- | |- | ||
− | | | + | | |
+ | | | ||
+ | Enrichment active | ||
+ | | | ||
+ | Enrichment inactive | ||
+ | | | ||
+ | Enrichment active | ||
+ | |} | ||
+ | |||
+ | |||
+ | Switching off the altitude-dependent enrichment suppression: LAMFAS = 0, TLAMFAS = 0 | ||
+ | |||
+ | |||
+ | Values for lambda | ||
+ | intervention lamfawkr_w during ignition angle retardation: | ||
+ | |||
+ | |||
+ | ZKLAMFAW: 2 s | ||
+ | |||
+ | ZKWLAFWL: 2 s | ||
+ | |||
+ | DLAMFAW: 0.01 | ||
+ | |||
+ | KFLAMKR: Engine speed sample points: Group characteristic SNM06GKUB | ||
+ | |||
+ | rl sample points: Group characteristic SRL06GKUB | ||
+ | |||
+ | Map values: All are 1.0 ® no weighting active | ||
+ | |||
+ | KFLAMKRL: dzlamfaw sample points: Group characteristic SDZ0 6GKUB | ||
+ | |||
+ | rl sample points: Group characteristic SRL06GKUB | ||
+ | |||
+ | Map values: All are 1.0 ® lambda intervention not active | ||
+ | |||
+ | DLAMTANS: Ambient temperature sample points: 50.25, 60, 70.5, 80.25 °C | ||
+ | |||
+ | Map values: All are 0 ® lambda intervention not active | ||
+ | |||
+ | KFLAFWL: Engine speed sample points: Group characteristic SNM06GKUB | ||
+ | |||
+ | rl sample points: Group characteristic SRL06GKUB | ||
+ | |||
+ | Map values: All are 0 ® lambda intervention not active | ||
+ | |||
+ | |||
+ | ''In the map, delta values are entered, –0.1 ''''®'' '' lamfwl_w = 0.9!'' | ||
+ | |||
+ | |||
+ | DLAMOB: Engine speed sample points: Group characteristic SNM06GKUB | ||
+ | |||
+ | Map values: All are 0 ® no additional enrichment during overboost | ||
+ | |||
+ | ''In the map, delta values are entered + 0.1 ''''®'' ''lamfa = lamfaw – 0.1!'' | ||
+ | |||
+ | RLLAMMN: Engine speed sample points: Group characteristic SNM06GKUB | ||
+ | |||
+ | Map values: 0% ® enrichment via LAMRLMN not active | ||
+ | |||
+ | LAMRLMN: Engine speed sample points: Group characteristic SNM06GKUB | ||
+ | |||
+ | Map values: 1.0 | ||
+ | ® lambda = 1.0 (no enrichment) | ||
+ | |||
+ | CWLAMFAW Bit 0: 0: dzwlamfaw = min (0, dzwwl) | ||
+ | |||
+ | 1: dzwlamfaw = min (0, (dzwwl + wkrma)). Default value = 0. | ||
+ | |||
+ | CWLAMFAW Bit 1: 0: LAMFAW also during torque reduction, e.g. via traction control, engine speed limiter, etc. active | ||
+ | 1: no enrichment via LAMFAW during torque reduction (milsol < mifa) | ||
+ | |||
+ | |||
+ | CWLAMFAW Bit 2: 0: B_ldeffw is always false ® emergency fuel tank breather also during | ||
+ | lamrlmn_w-intervention active | ||
+ | 1: B_ldeffw dependent on lamrlmn_w-activation, when B_ldeffw = true, | ||
+ | emergency fuel tank breather disabled, i.e. fuel tank breather valve shuts. | ||
+ | |||
+ | |||
+ | CWLAMFAW Bit 3: 0: Disable driver’s requested lambda activation through catalyst heating enabled | ||
+ | 1: Disable driver’s requested lambda activation through catalyst heating not possible | ||
+ | |||
+ | CWLAMFAW Bit 4: 0: lamfwl_w dependent on B_stend and VZ1-term | ||
+ | 1: lamfwl_w not dependent on B_stend and VZ1-term | ||
+ | |||
+ | |||
+ | Group characteristic for engine speed sample points: SNM06GKUB: 760, 1520, 2560, 3520, 4560, 5520 rpm | ||
+ | |||
+ | Group characteristic for relative load sample points: SRL06GKUB: 20, 40, 60, 80, 90 % | ||
+ | |||
+ | Group characteristic for engine temperature sample points: STM0 8GKUB: –15, 0, 20, 40.5, 60, 75, 85.5, 105 °C | ||
+ | |||
+ | Group characteristic for dzwlamfaw sample points: SDZ06GKUB: –30, –20, –15, –10, –5, 0 degrees | ||
+ | |||
+ | {| border="1" | ||
|- | |- | ||
− | | | + | | |
+ | '''Parameter''' | ||
+ | | | ||
+ | '''Description''' | ||
|- | |- | ||
− | | | + | | |
+ | CWLAMFAW | ||
+ | | | ||
+ | Codeword LAMFAW | ||
|- | |- | ||
− | | | + | | |
+ | DLAMFAW | ||
+ | | | ||
+ | Threshold | ||
+ | value for activating enrichment via driver’s request | ||
|- | |- | ||
− | | | + | | |
+ | DLAMOB | ||
+ | | | ||
+ | Delta lambda during overboost | ||
|- | |- | ||
− | | | + | | |
+ | DLAMTANS | ||
+ | | | ||
+ | Air temperature-dependent | ||
+ | enrichment | ||
|- | |- | ||
− | | | + | | |
+ | GANGFAW | ||
+ | | | ||
+ | Gear | ||
+ | threshold for deactivating driver’s request at altitude | ||
|- | |- | ||
− | | | + | | |
+ | KFLAFWL | ||
+ | | | ||
+ | Offset engine target lambda | ||
|- | |- | ||
− | | | + | | |
+ | KFLAMKR | ||
+ | | | ||
+ | Weighting | ||
+ | factor for enrichment during ignition angle retardation | ||
|- | |- | ||
− | | | + | | |
+ | KFLAMKRL | ||
+ | | | ||
+ | Enrichment | ||
+ | during ignition angle retardation | ||
|- | |- | ||
− | | | + | | |
+ | LAMFA | ||
+ | | | ||
+ | Driver’s requested lambda | ||
|- | |- | ||
− | | | + | | |
+ | LAMFAS | ||
+ | | | ||
+ | Disable driver’s requested | ||
+ | lambda | ||
|- | |- | ||
− | | | + | | |
+ | LAMRLMN | ||
+ | | | ||
+ | Lambda | ||
+ | control when rl < RLLAMMN to improve the combustion efficiency | ||
|- | |- | ||
− | | | + | | |
+ | RLLAMMN | ||
+ | | | ||
+ | Minimum | ||
+ | requested load threshold for enrichment due to combustion efficiency | ||
|- | |- | ||
− | | | + | | |
+ | SDZ06GKUB | ||
+ | | | ||
+ | Sample | ||
+ | point distribution for KFLAMKRL | ||
|- | |- | ||
− | | | + | | |
+ | SNM06GKUB | ||
+ | | | ||
+ | Sample | ||
+ | point distribution for KFLAMKR, DLAMOB | ||
|- | |- | ||
− | | | + | | |
+ | SRL06GKUB | ||
+ | | | ||
+ | Sample | ||
+ | point distribution for KFLAMKRL, KFLAFWL, KFLAMKR | ||
|- | |- | ||
− | | | + | | |
+ | STM08GKUB | ||
+ | | | ||
+ | 8 engine | ||
+ | temperature sample point distribution for KFLAFWL | ||
|- | |- | ||
− | | | + | | |
+ | SY TURBO | ||
+ | | | ||
+ | System constant: turbocharger | ||
|- | |- | ||
− | + | | | |
− | + | TLAFA | |
− | + | | | |
− | + | Delay time | |
− | + | with driver’s requested lambda active | |
|- | |- | ||
− | | | + | | |
+ | TLAMFAS | ||
+ | | | ||
+ | Delay time | ||
+ | with driver’s requested lambda at altitude active | ||
|- | |- | ||
− | | | + | | |
+ | TMSTFWMN | ||
+ | | | ||
+ | Minimum | ||
+ | engine start temperature for deactivating driver’s request at altitude | ||
|- | |- | ||
− | | | + | | |
+ | TMSTFWMX | ||
+ | | | ||
+ | Maximum | ||
+ | engine start temperature for deactivating driver’s request at altitude | ||
|- | |- | ||
− | | | + | | |
+ | TNSTFWMN | ||
+ | | | ||
+ | Minimum | ||
+ | time after start for deactivating driver’s request at altitude | ||
|- | |- | ||
− | | | + | | |
+ | TNSTFWMX | ||
+ | | | ||
+ | Maximum | ||
+ | time after start for deactivating driver’s request at altitude | ||
|- | |- | ||
− | | | + | | |
+ | ZKLAMFAW | ||
+ | | | ||
+ | Time | ||
+ | constant filtering enrichment via driver’s request | ||
|- | |- | ||
− | | | + | | |
+ | ZKWLAFWL | ||
+ | | | ||
+ | Time | ||
+ | constant weighting offset engine target lambda | ||
|- | |- | ||
− | | | + | | |
+ | '''Variable''' | ||
+ | | | ||
+ | '''Description''' | ||
|- | |- | ||
− | | | + | | |
+ | B_KH | ||
+ | | | ||
+ | Condition flag: catalyst | ||
+ | heating | ||
|- | |- | ||
− | | | + | | |
+ | B_LAMFAS | ||
+ | | | ||
+ | Condition | ||
+ | flag: disable driver’s requested lambda | ||
|- | |- | ||
− | | | + | | |
+ | B_LAMFASA | ||
+ | | | ||
+ | Condition | ||
+ | flag: altitude-dependent disabling time for driver’s requested lambda is | ||
+ | required | ||
|- | |- | ||
− | | | + | | |
+ | B_LAMFASH | ||
+ | | | ||
+ | Condition | ||
+ | flag: altitude-dependent disabling time for driver’s requested lambda is active | ||
|- | |- | ||
− | | | + | | |
+ | B_LDEFFW | ||
+ | | | ||
+ | Condition | ||
+ | flag: defined target lambda (cylinder bank 1) via driver’s request | ||
|- | |- | ||
− | | | + | | |
+ | B_LDOB | ||
+ | | | ||
+ | Condition flag: overboost | ||
+ | active | ||
|- | |- | ||
− | | | + | | |
+ | B_SAB | ||
+ | | | ||
+ | Condition | ||
+ | flag: overrun fuel cut-off readiness | ||
|- | |- | ||
− | | | + | | |
+ | B_STEND | ||
+ | | | ||
+ | Condition | ||
+ | flag: end of start conditions reached | ||
|- | |- | ||
− | | | + | | |
+ | DZWLAMFAW | ||
+ | | | ||
+ | Delta | ||
+ | ignition angle during knock control intervention or warm-up for enrichment | ||
+ | via lambda | ||
|- | |- | ||
− | | | + | | |
+ | DZWWL | ||
+ | | | ||
+ | Delta | ||
+ | ignition angle during warm-up | ||
|- | |- | ||
− | | | + | | |
+ | FHO | ||
+ | | | ||
+ | Altitude correction factor | ||
|- | |- | ||
− | | | + | | |
+ | GANGI | ||
+ | | | ||
+ | Actual gear | ||
|- | |- | ||
− | | | + | | |
+ | LAMFAWKR_W | ||
+ | | | ||
+ | during ignition angle retardation | ||
+ | (knock control), WL | ||
|- | |- | ||
− | | | + | | |
+ | LAMFAWS W | ||
+ | | | ||
+ | Driver’s | ||
+ | requested target lambda steady-state part | ||
|- | |- | ||
− | | | + | | |
+ | LAMFAW_W | ||
+ | | | ||
+ | Driver’s | ||
+ | requested target lambda part from map LAMFA | ||
|- | |- | ||
− | | | + | | |
+ | LAMFA_W | ||
+ | | | ||
+ | Driver’s | ||
+ | requested target lambda (word) | ||
|- | |- | ||
− | | | + | | |
+ | LAMFWL_W | ||
+ | | | ||
+ | Offset | ||
+ | engine target lambda during warm-up | ||
|- | |- | ||
− | | | + | | |
+ | LAMRLMN_W | ||
+ | | | ||
+ | Target | ||
+ | lambda control to improve the combustion efficiency at lower relative loads | ||
|- | |- | ||
− | | | + | | |
+ | MIFA_W | ||
+ | | | ||
+ | Indexed driver’s | ||
+ | requested engine torque | ||
|- | |- | ||
− | | | + | | |
− | | | + | MILSOL_W |
− | + | | | |
− | + | Driver’s | |
− | + | requested torque for cylinder charge path | |
− | + | |- | |
− | + | | | |
− | + | MRFA_W | |
− | + | | | |
− | + | Relative driver’s | |
− | + | requested torque from cruise control and throttle pedal | |
− | + | |- | |
− | + | | | |
− | + | NMOT | |
− | + | | | |
− | + | Engine speed | |
− | + | |- | |
− | + | | | |
− | + | RL | |
− | + | | | |
− | + | Relative cylinder charge | |
− | + | |- | |
− | + | | | |
− | + | TANS | |
− | + | | | |
− | + | Ambient air temperature | |
− | + | |- | |
− | + | | | |
− | + | TMOT | |
− | + | | | |
− | + | Engine temperature | |
− | + | |- | |
− | + | | | |
− | + | TMST | |
− | + | | | |
− | + | Engine start temperature | |
− | + | |- | |
− | + | | | |
− | + | TNST_W | |
− | + | | | |
− | + | Time after | |
− | + | end of start conditions | |
− | + | |- | |
− | + | | | |
− | + | WKRMA | |
− | + | | | |
− | + | Average | |
− | + | value of the individual cylinder ignition angle retardation (knock control), | |
− | + | general (in emergency mode with safety margin) | |
− | + | |} | |
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[[Category:ME7]] | [[Category:ME7]] |
Revision as of 07:04, 4 December 2011
See the funktionsrahmen for the following diagrams:
lamfaw-lamfaw
lamfaw-lamkr
lamfaw-lamwl
lamfaw-lamfadisable
lamfaw-lamrlmin
lamfaw-initialise
Function Description
The function LAMFAW brings about an enrichment of the fuel-air mixture via lamfa_w when the driver demands maximum torque via mrfa_w. This then corresponds to the full-load enrichment. The intervention to the mixture via lamfa_w can be delayed via the delay time TLAFA. During turbocharger overboost, an additional enrichment is applied by a delta-lambda from the characteristic DLAMOB.
For the time TLAMFAS, an enrichment via the driver’s request as a function of altitude (LAMFAS) can be prevented (see sub-function LAMFADISABLE). Triggering of this time will be initiated if B_kh = true, LAMFA <1.0 and the altitude at which the function is disabled (as defined in LAMFAS) has been reached.
In this way, a reproducible driving cycle can also be achieved at higher altitudes.
During a torque reduction, e.g. traction control intervention, engine speed limiter …, the enrichment via the map LAMFAW can be disabled by setting CWMFAW Bit 1 = true.
In the sub-function LAMKR, an enrichment can be implemented during ignition angle intervention.
The sub-function LAMWL can be used for the enrichment during warm-up. If this procedure is used, tank-venting via the function LAMKO is not switched off.
In the sub-function LAMRLMIN, an enrichment via LAMRLMN is active for low loads (rl). This improves the combustion efficiency at low loads. If CWLAMFAW bit 2 is set, then the emergency fuel tank breather is disabled during lamrlmn-intervention.
Application Notes
A delay time TLAFA > 0 can only be applied when the mixture intervention via lamfa_w should be delayed.
Map LAMFA:
Engine speed sample points: 1000, 1400, 1800, 2200, 2600, 3000, 3400, 3800, 4200, 4600, 5000, 5400, 5800, 6200, 6600, 7000 rpm
mrfa_w sample points: 70, 80, 90, 100, 110, 120 %
Map values of 1.0
DLAMOB comprises the delta-lambda, so that an additional mixture enrichment is implemented in overboost mode.
Sample points for engine speed: implemented as a group characteristic SNM06GKUB
Neutralization of the function by data:
LAMFA = 1.0 and DLAMOB = 0.0 ® lamfa_w is then 1.0
The time TLAMFAS must be selected so that no large gradients are caused in the driver’s requested enrichment (typically 240 s).
The characteristic LAMFAS contains values from 0 to 1. If the value is 0, enrichment via the altitude effect is active. Values other than 0 deactivate enrichment via LAMFA, if B_kh = true and LAMFA values are < 1.0.
The characteristic LAMFAS is not interpolated, which means that the characteristic initial value remains constant until a node is crossed.
For the fho-sample points of the characteristic LAMFAS, the following relationship applies: fho = 1
– altitude [m]/10,000 m
Since the variable fho has a quantization of 4/256 = 0.015625, this resolution must be considered when determining the switch-off. Similarly, there is a potential altitude deviation of ± 250 m because of the sensor tolerance.
For the calculation of the lower or upper threshold of fho, the following relationship applies for a nominal altitude cut-off threshold:
Lower altitude cut-off threshold:
fho [phys] = 1 – ((nominal altitude [m] – 250 m ) /10000) ® fho[Ink] = Integer (fho[phys]/0.015625) + 1Ink
® fho upper limit [phys] = (1 – fho[Ink] x 0.015625)
® Altitude upper limit = (1 – fho upper limit [phys]) x 10000
Upper altitude cut-off threshold:
fho [phys] = 1 – ((nominal altitude [m] + 250 m) /10000)
® fho[Ink] = Integer (fho[phys] /0.015625)
® fho lower limit [phys] = fho[Ink] x 0.015625
® Altitude lower limit = (1 – fho lower limit [phys]) ´ 10000
This produces the following values:
Nominal altitude |
2,200 m |
1,600 m |
|
Altitude upper limit |
2,500 m |
1,875 m |
The altitude upper limit is the fho lower limit! |
fho lower limit |
0.75 |
0.8125 | |
Altitude lower limit |
1,875 m |
1,250 m |
|
fho upper limit |
0.8125 |
0.875 |
Thus, the characteristic LAMFAS is parameterized as follows for the nominal altitude of
2,200 m:
fho |
0.734375 |
0.7500 |
0.8125 |
Value |
0 |
1 |
0 |
Enrichment active |
Enrichment inactive |
Enrichment active |
Switching off the altitude-dependent enrichment suppression: LAMFAS = 0, TLAMFAS = 0
Values for lambda
intervention lamfawkr_w during ignition angle retardation:
ZKLAMFAW: 2 s
ZKWLAFWL: 2 s
DLAMFAW: 0.01
KFLAMKR: Engine speed sample points: Group characteristic SNM06GKUB
rl sample points: Group characteristic SRL06GKUB
Map values: All are 1.0 ® no weighting active
KFLAMKRL: dzlamfaw sample points: Group characteristic SDZ0 6GKUB
rl sample points: Group characteristic SRL06GKUB
Map values: All are 1.0 ® lambda intervention not active
DLAMTANS: Ambient temperature sample points: 50.25, 60, 70.5, 80.25 °C
Map values: All are 0 ® lambda intervention not active
KFLAFWL: Engine speed sample points: Group characteristic SNM06GKUB
rl sample points: Group characteristic SRL06GKUB
Map values: All are 0 ® lambda intervention not active
In the map, delta values are entered, –0.1 '® lamfwl_w = 0.9!
DLAMOB: Engine speed sample points: Group characteristic SNM06GKUB
Map values: All are 0 ® no additional enrichment during overboost
In the map, delta values are entered + 0.1 '® lamfa = lamfaw – 0.1!
RLLAMMN: Engine speed sample points: Group characteristic SNM06GKUB
Map values: 0% ® enrichment via LAMRLMN not active
LAMRLMN: Engine speed sample points: Group characteristic SNM06GKUB
Map values: 1.0 ® lambda = 1.0 (no enrichment)
CWLAMFAW Bit 0: 0: dzwlamfaw = min (0, dzwwl)
1: dzwlamfaw = min (0, (dzwwl + wkrma)). Default value = 0.
CWLAMFAW Bit 1: 0: LAMFAW also during torque reduction, e.g. via traction control, engine speed limiter, etc. active 1: no enrichment via LAMFAW during torque reduction (milsol < mifa)
CWLAMFAW Bit 2: 0: B_ldeffw is always false ® emergency fuel tank breather also during
lamrlmn_w-intervention active
1: B_ldeffw dependent on lamrlmn_w-activation, when B_ldeffw = true,
emergency fuel tank breather disabled, i.e. fuel tank breather valve shuts.
CWLAMFAW Bit 3: 0: Disable driver’s requested lambda activation through catalyst heating enabled
1: Disable driver’s requested lambda activation through catalyst heating not possible
CWLAMFAW Bit 4: 0: lamfwl_w dependent on B_stend and VZ1-term 1: lamfwl_w not dependent on B_stend and VZ1-term
Group characteristic for engine speed sample points: SNM06GKUB: 760, 1520, 2560, 3520, 4560, 5520 rpm
Group characteristic for relative load sample points: SRL06GKUB: 20, 40, 60, 80, 90 %
Group characteristic for engine temperature sample points: STM0 8GKUB: –15, 0, 20, 40.5, 60, 75, 85.5, 105 °C
Group characteristic for dzwlamfaw sample points: SDZ06GKUB: –30, –20, –15, –10, –5, 0 degrees
Parameter |
Description |
CWLAMFAW |
Codeword LAMFAW |
DLAMFAW |
Threshold value for activating enrichment via driver’s request |
DLAMOB |
Delta lambda during overboost |
DLAMTANS |
Air temperature-dependent enrichment |
GANGFAW |
Gear threshold for deactivating driver’s request at altitude |
KFLAFWL |
Offset engine target lambda |
KFLAMKR |
Weighting factor for enrichment during ignition angle retardation |
KFLAMKRL |
Enrichment during ignition angle retardation |
LAMFA |
Driver’s requested lambda |
LAMFAS |
Disable driver’s requested lambda |
LAMRLMN |
Lambda control when rl < RLLAMMN to improve the combustion efficiency |
RLLAMMN |
Minimum requested load threshold for enrichment due to combustion efficiency |
SDZ06GKUB |
Sample point distribution for KFLAMKRL |
SNM06GKUB |
Sample point distribution for KFLAMKR, DLAMOB |
SRL06GKUB |
Sample point distribution for KFLAMKRL, KFLAFWL, KFLAMKR |
STM08GKUB |
8 engine temperature sample point distribution for KFLAFWL |
SY TURBO |
System constant: turbocharger |
TLAFA |
Delay time with driver’s requested lambda active |
TLAMFAS |
Delay time with driver’s requested lambda at altitude active |
TMSTFWMN |
Minimum engine start temperature for deactivating driver’s request at altitude |
TMSTFWMX |
Maximum engine start temperature for deactivating driver’s request at altitude |
TNSTFWMN |
Minimum time after start for deactivating driver’s request at altitude |
TNSTFWMX |
Maximum time after start for deactivating driver’s request at altitude |
ZKLAMFAW |
Time constant filtering enrichment via driver’s request |
ZKWLAFWL |
Time constant weighting offset engine target lambda |
Variable |
Description |
B_KH |
Condition flag: catalyst heating |
B_LAMFAS |
Condition flag: disable driver’s requested lambda |
B_LAMFASA |
Condition flag: altitude-dependent disabling time for driver’s requested lambda is required |
B_LAMFASH |
Condition flag: altitude-dependent disabling time for driver’s requested lambda is active |
B_LDEFFW |
Condition flag: defined target lambda (cylinder bank 1) via driver’s request |
B_LDOB |
Condition flag: overboost active |
B_SAB |
Condition flag: overrun fuel cut-off readiness |
B_STEND |
Condition flag: end of start conditions reached |
DZWLAMFAW |
Delta ignition angle during knock control intervention or warm-up for enrichment via lambda |
DZWWL |
Delta ignition angle during warm-up |
FHO |
Altitude correction factor |
GANGI |
Actual gear |
LAMFAWKR_W |
during ignition angle retardation (knock control), WL |
LAMFAWS W |
Driver’s requested target lambda steady-state part |
LAMFAW_W |
Driver’s requested target lambda part from map LAMFA |
LAMFA_W |
Driver’s requested target lambda (word) |
LAMFWL_W |
Offset engine target lambda during warm-up |
LAMRLMN_W |
Target lambda control to improve the combustion efficiency at lower relative loads |
MIFA_W |
Indexed driver’s requested engine torque |
MILSOL_W |
Driver’s requested torque for cylinder charge path |
MRFA_W |
Relative driver’s requested torque from cruise control and throttle pedal |
NMOT |
Engine speed |
RL |
Relative cylinder charge |
TANS |
Ambient air temperature |
TMOT |
Engine temperature |
TMST |
Engine start temperature |
TNST_W |
Time after end of start conditions |
WKRMA |
Average value of the individual cylinder ignition angle retardation (knock control), general (in emergency mode with safety margin) |