LAMKO 9.80 (Lambda Coordination)

From Nefmoto

Jump to: navigation, search

See the funktionsrahmen for the following diagrams:

lamko-main: Function overview

lamko-lamsel: Sub-function: lambda target selection for cylinder bank 1: LAMSEL

lamko-lamsel2: Sub-function: lambda target selection for cylinder bank 2: LAMSEL2

lamko-lamlim: Sub-function: LAMLIM: lambda limit engine running

lamko-lamkh: Sub-function: lambda intervention for catalyst heating in cylinder bank 1: LAMKH

lamko-lamkh2: Sub-function: lambda intervention for catalyst heating in cylinder bank 2: LAMKH2

lamko-lamdsk: Sub-function: lambda intervention for diagnosis (cylinder bank 1): LAMDSK

lamko-lamdsk2: Sub-function: lambda intervention for diagnosis (cylinder bank 2): LAMDSK2

lamko-lss1kor: Sub-function: lambda target correction via lambda probe (cylinder bank 1): LSS1KOR

lamko-lss2kor: Sub-function: lambda target correction via lambda probe (cylinder bank 2): LSS2KOR

lamko-init: Initialisation values:


Function Description

Lambda = 1.0 will be specified in the combustion chamber through the pilot control of fuel injection in module ESVST 4.20. The lambda coordination function LAMKO specifies which engine operating point the combustion chamber operates at lambda = 1.0. The position of the switch is a measure of the priority of the corresponding lambda intervention.


The highest priority is catalyst protection (LASOAB), followed by component protection or driver’s desired value then catalyst clear out and catalyst heating.


Component protection for manifold(s), exhaust valve(s) and turbocharger(s) is implemented via the inputs lambts_w and lambts2_w. The input lambts2_w is only available if the system constant SY_STERBTS = true. This is only set for projects with stereo exhaust tracts which occurs when the two banks have very different exhaust gas temperatures for the engine same operating point.


For projects with exhaust gas temperature control via exhaust gas temperature sensors, correction control of the additive part dlamatr_w is included.


From start to end of warm-up lamnswl_w is active unless catalyst heating through secondary air is requested.


At the beginning of catalytic converter heating, a factor flakh from module LAKH for lamnswl_w is passed to lambda for catalyst heating lamkh_w. When catalyst heating is terminated it is passed back again with flakh to lamnswl_w. For systems with secondary air injection (B_slsfz), the lambda engine target (lamsbg_w) is calculated by means of the secondary air dilution arising from target lambda at the lambda probe lamsons_w via multiplication by the secondary air dilution factor flamsl_w.


The two sub-functions LSS1KOR and LSS2KOR correct the rounding error in the calculation of lamsons_w about 1.0 so that two-point lambda control is not unnecessarily shut down.


In normal operation, the lambda target (lamsbg) is provided by lamfa_w or lambts_w.


The two inputs lamlash_w and lamelsh_w are provided for diagnosis of the post-catalyst lambda probes. With these inputs, a change in the post-cat lambda probe voltage via a lambda intervention is implemented.


For catalyst diagnosis, lamdskt_w or lamdskt2_w are designated for the future of lambda intervention. This intervention is activated by condition flags B_lamdkt or B_dlamdkt2 whereas the intervention with index 2 is only available with SY_STERVK or SY_STERHK.


On catalyst clear-out, the target lambda is determined by lamka unless an even richer mixture is requested via lamnswl_w (especially when the engine is still cold).


Via the lambda intervention lamau_w, the exhaust emission test AU implements a lambda intervention for the catalyst check. For this purpose the system constant SY_AAU must be set in the project. The intervention is implemented when B_auakt = true.


At fuel injector switch off (B_evab, Bevab2 = true) the target lambda value is specified by the constant LASOAB. Thus, this can be achieved that in the associated exhaust tract of the deactivated cylinders so that no surplus hydrocarbons arise in the other cylinders when the entire cylinder bank is operated under lean conditions (e.g. LASOAB = 1.05) for catalyst protection.


For the torque calculation, the basic-lambda variable lambas is made available as the average of the two cylinder banks.


When a high lambda-dynamic situation occurs outside of warm-up, the catalytic converter heating range (B_lamnse = true) is no longer required and the computation time frame is transferred from 10 ms to 100 ms.


Then, via the switches, the actually selected lambda (lamsubg_w) is limited via either of the two lambda thresholds LAMLGFTM (or LAMFLGSL with secondary air operation) and LAMLGMTM to the rich and lean engine operating limits.


If the lambda requirements for diagnostic functions, catalyst clear out or catalyst heating are active, the fuel tank breather must be prohibited, so that it serves bit B_lamsdef or either B_ldef and B_ldef2 for twin cylinder bank systems.


IMPORTANT: It must be ensured that the lean operating limits LAMLGMTM & LAMLGMKT do not go in the direction of zero because it directly affects the injection!


Application Notes

Data for initial application:


CWLAMKH = 0

LASOAB 1.05

LAMLGFTM = LAMFLGSL = 0.77

Sample points for LAMFLGSL: imlatm = 2, 4, 6, 8, 10, 12 kg

LAMLGMTM sample points for tmot are not freely selectable, since the group tmot line is a function of ESWL

Value = 1.2

LAMSOSUF = 0.998779

LAMSOSOF = 1.001221 equivalent to 5 increments difference of 1.0

The inputs lamka_w and lamka2_w are inactive if the lambda value ³ 2. The catalyst clear out function sets this value in the inactive case at lambda = 8.0.

CWLAMKH = 1: Minimum value of lamnswl_w or lamkhe_w to act CWLAMKH = 0: lamkhe acts directly


Abbreviations

Parameter

Description

CWLAMKH

Code word for lambda coordination during catalyst heating

LAMFLGSL

Lambda engine operating limit fett bei Sekundärlufteinblasung

LAMLGFKT

Rich lambda operating limit during short test

LAMLGFTM

Rich lambda operating limit

LAMLGMKT

Lean lambda operating limit during short test

LAMLGMTM

Lean lambda operating limit

LAMSOSOF

Lambda probe target upper limit for 1.0-window

LAMSOSUF

Lambda probe target lower limit for 1.0-window

LASOAB

Target lambda value during cylinder bank deactivation

STM12ESUB

Sample point distribution for engine temperature (tmot)

SY_AAU

System constant: calibrator specification of target lambda for exhaust emissions test (AU) is possible

SY_ATR

System constant: exhaust gas temperature control is available

SY_DKAT

System constant: status information about the system’s available catalyst diagnostics

SY_DLSHV

System constant: condition module DLSHV (post-catalyst probe swapping) available

SY_STERBTS

System constant: exhaust gas bank selective component protection

SY_STERHK

System constant: condition stereo lambda control post-catalyst

SY_STERVK

System constant: condition stereo lambda control pre-catalyst

Variable

Description

B_AUAKT

Condition flag: exhaust emissions test active

B_BEVAB

Condition flag: injector shut-off in cylinder bank 1

B_BEVAB2

Condition flag: injector shut-off in cylinder bank 2

B_DSLA

Adaptation phase: determining secondary air mass

B_FA

Condition flag: general function requirement

B_FALSH

Condition flag: function requirement post-catalyst lambda probe for cylinder bank 1

B_FALSH2

Condition flag: function requirement post-catalyst lambda probe for cylinder bank 2

B_FASLA

Condition flag: external requirement to activate secondary air

B_KH

Condition flag: catalyst heating

B_LALGF

Condition flag: rich lambda operating limit active (cylinder bank 1)

B_LALGF2

Condition flag: rich lambda operating limit active (cylinder bank 2)

B_LAMBTS

Lambda for component protection is active (cylinder bank 1)

B_LAMBTS2

Lambda for component protection is active (cylinder bank 2)

B_LAMDIAG

Target lambda for diagnostic function requirement

B_LAMDKT

Lambda target intervention for catalyst diagnose active

B_LAMDKT2

Lambda target intervention for catalyst diagnose active

B_LAMKA

Lambda for catalyst clear out active

B_LAMKA2

Lambda for catalyst clear out active

B_LAMKH

Condition flag: target lambda for catalyst heaing active

B_LAMKHE

No lambda requirement from module LAKH

B_LAMLASH

Condition flag for enleanment in module LAMKO (cylinder bank 1)

B_LAMLASH2

Condition flag for enleanment in module LAMKO (cylinder bank 2)

B_LAMLSHV

Condition flag for enleanment or enrichment in module LAMKO

B_LAMLSHV2

Condition flag for enleanment or enrichment in module LAMKO Bank 2

B_LAMNSE

Condition flag: end of lamns_w calculation

B_LAMNSWL

Lambda engine target for post-start and warm-up active

B_LAMSDEF

Condition flag: defined target lambda

B_LDEF

Condition flag: defined target lambda (cylinder bank 1)

B_LDEF2

Condition flag: defined target lambda (cylinder bank 2)

B_LDEFFW

Condition flag: defined target lambda (cylinder bank 1) via driver’s request

B_SLS

Condition flag: secondary air control active

B_SLSFZ

Condition flag: secondary air control is installed in the vehicle

DLAMATR W

Delta target lambda from exhaust gas temperature regulation (cylinder bank 1)

DLAMATR2_W

Delta target lambda from exhaust gas temperature regulation (cylinder bank 2)

FLAMKH

Factor for controlling lambda-engine target during catalyst heaing

FLAMSL_W

Factor for lambda adjustment via secondary air (cylinder bank 1)

FLAMSL2_W

Factor for lambda adjustment via secondary air (cylinder bank 2)

IMLATM

Integrated air mass flow from engine start to the maximum value

LAMAU_W

Lambda for exhaust emission test

LAMBAS

Basic lambda

LAMBTS_W

Lambda for component protection (cylinder bank 1)

LAMBTS2_W

Lambda for component protection (cylinder bank 2)

LAMDKT_W

Target lambda for catalyst diagnostics (cylinder bank 1)

LAMDKT2_W

Target lambda for catalyst diagnostics (cylinder bank 2)

LAMELSH_W

Target lambda for electric probe diagnostics post-catalyst (Kurztrip, cylinder bank 1)

LAMELSH2_W

Target lambda for electric probe diagnostics post-catalyst (Kurztrip, cylinder bank 2)

LAMFA_W

Target driver’s requested lambda (word)

LAMKA_W

Target lambda value catalyst clear out (cylinder bank 1)

LAMKA2_W

Target lambda value catalyst clear out (cylinder bank 2)

LAMKH_W

Lambda-engine target during catalyst heaing (word, cylinder bank 1)

LAMKH2 W

Lambda-engine target during catalyst heaing (word, cylinder bank 2)

LAMKHE_W

Lambda-engine target during catalyst heaing, effective (cylinder bank 1)

LAMKHE2_W

Lambda-enging target during catalyst heaing, effective (cylinder bank 2)

LAMLASH_W

Target lambda for test vibration check post-catalyst (cylinder bank 1)

LAMLASH2_W

Target lambda for test vibration check post-catalyst (cylinder bank 2)

LAMLGFMN

Lambda engine rich operating limit

LAMLGM

Lean lambda operating limit

LAMLSHV_W

Target lambda for test post-catalyst probe substitution (cylinder bank 1)

LAMLSHV2_W

Target lambda for test post-catalyst probe substitution (cylinder bank 2)

LAMNSWL_W

Lambda-engine target for post-start and warm-up

LAMS2_W

Target lambda (word)

LAMSBG_W

Target lambda limit (word, cylinder bank 1)

LAMSBG2_W

Target lambda limit (word, cylinder bank 2)

LAMSONS_W

Target lambda value based on the lambda probe installation location (cylinder bank 1)

LAMSONS2_W

Target lambda value based on the lambda probe installation location (cylinder bank 2)

LAMSOS_W

Target lambda value based on the lambda probe installation location (cylinder bank 1)

LAMSOS2_W

Target lambda value based on the lambda probe installation location (cylinder bank 2)

LAMSUBG_W

Unlimited target lambda (word, cylinder bank 1)

LAMSUBG2_W

Unlimited target lambda (word, cylinder bank 2)

LAMS_W

Target lambda (word)

LAMVOA_W

Lambda pilot control without additive part (cylinder bank 1)

LAMVOA2 W

Lambda pilot control without additive part (cylinder bank 2)

TMOT

Engine temperature

Personal tools