Calculation of basic parameters for torque interface (MDBAS)

From Nefmoto

Jump to: navigation, search

This is a translation from the Funktionsrahmen

MDBAS abbreviations

Parameter Source-X Source-Y Type Designation
Parameter Source-X Source-Y Type Designation
AGRRMAX FW maximum possible EGR rate
WMDBAS FW code word Including the ZW correction for EGR operation
ZWNWSUE WNWUE KL Delta ignition point depending on camshaft overlap
ZWOLA LAMBAS KL Lambda-dependence of the optimal ignition angle relative to lambda 1
ZWOM TMOT KL temperature dependent offset of the optimal ZW
TADZW DZWB KL ZW-efficiency as a function of delta ZW
TALAM LAMBAS KL Lambda-efficiency
FDZWOAGR NMOT_W RL_W KF Offset of the optimal operation with AGR ZW
FMIOP NMOT_W RL_W KF Map optimum engine torque
FZWOP NMOT_W RL_W KF optimum firing angle
FZWOP2 NMOT_W RL_W KF optimum firing angle variation 2
Variable Source Type Designation
AGRR BGSRM EIN Exhaust gas recirculation rate
B_AGR EIN A condition AGR
DZWOAG MDBAS AUS exhaust gas recirculation rate dependent optimum ignition angle of the ZW
DZWOL MDBAS AUS lambda dependent of the optimal ignition angle ZW
DZWOTM MDBAS DOK temperature-dependent optimal ignition angle of the ZW
ETALAB MDBAS AUS Lambda efficiency without intervention, based on optimum torque at lambda = 1
ETATRMN MDBAS AUS minimum value in the efficiency drum
ETAZWB MDBAS AUS Ignition angle of the basic ignition angle
ETAZWBM MDBAS AUS averaged ignition angle of the basic ignition angle
FNWUE NWWUE EIN Weighting factor overlap camshafts (intake)
MIBAS_W MDBAS AUS indexed base torque
MIOPTL1_W MDBAS DOK optimal indexed engine torque at lambda = 1
MIOPT_W MDBAS AUS best indexed time
RL_W EGFE EIN relative air charge (Word)
R_SYN GGDPG EIN Synchro-grid
SY_NWS PROKONAL EIN System constant cam timing: no, 2-pt. or continuous
TMOT GGTFM EIN Motor temperature
WNWUE NWWUE EIN Camshaft overlap angle
ZWBAS ZUE EIN Base ignition
ZWOPT MDBAS AUS optimum firing angle

MDBAS Functional Description

Calculate the optimum moment mioptl1_w at lambda = 1 with the characteristic field KFMIOP. Edit this moment about the Lambda influence by multiplying by the Lambda efficiency etalab. The oxygen efficiency is made of the characteristic ETALAM obtained. By multiplying by the ignition angle to the base torque is mibas. This corresponds the indicated torque that sets in when the combustion to the base Lambda lambas and the base ignition zwbas takes place.

Determine the optimum ignition angle at lambda = 1 on the map KFZWOP. The partial function ZW_NWS describes the influence of the optimum firing angle may depend on an existing valve timing (NWS). The measures provided for equipment options are not, 2-point or continuous NWS. In the case of the 2-point control is through the factor fnwue steadily between KFZWOP and the map KFZWOP2 switched. For steady NWS is dependent on the NW-overlapping angle wnwue a ZW correction added to KFZWOP. The determined optimum ignition angle zwoptl1 applies again for lambda = 1 The currently valid NWS version is determined by the system constant SY_NWS at the SW creation:

SY_NWS = 0: No NWS
       = 1: 2-point NWS
       = 2: continuous NWS
       > 2: not defined.

The software is translated conditionally, i.e. it is only a variation in EPROM. SY_NWS is not in the EPROM and not to apply.

Additive corrections depending on lambda, the exhaust gas recirculation rate AGRR and the engine temperature is taken into account. The resulting firing angle zwopt now forms the basis for the ignition angle efficiency calculation. The basic ignition angle efficiency is calculated by the characteristic ETADZW, the input variable is the difference formed between zwopt and zwbas. This is followed by an averaging of the basis of efficiency across all cylinders and it is the basis of efficiency etazwbm.

The ZW-correction for EGR operation is be the code word CWMDBAS either included or accessible only B_agr = true. A case of permanent calculation ZW-jumps are avoided by switching off B_agr.

MDBAS Application Notes

EGR inactive at all the measurements! For the parameterization, the following measurements are taken:

  1. Lambda = 1 operation:
    • Firing angle grinding on the engine test stand at lambda = 1 on the following operating points, the engine is warm:
 n = 500,750,1000,1250,1500,2000,2500,3000,3500,4000,4500,5000,5500,6000,6500 (if possible) rpm
 rl = 10,20,30,40,50,60,70,80,90,100%
    • The firing angle grinding start firing angle at which the maximum torque is achieved (if not movable at the knock limit). In steps of 4.5 degrees KW is now adjusted in the late direction until the deadlines are moveable firing angle is achieved. The following data are taking notes for each measuring point: nmot, rl, lambda, clutch torque, ignition angle.
  1. Lambda function
    • Zw loops over lambda at the measuring points:
 n = 1000, 2000, 3000 rpm
 rl = 30, 50, 70%
 Lambda = .8, .85, .9, .95,1,1.05,1.1,1.15,1.2
 Measurements as above
  1. Drag torque
    • For all measurement points at 1 must present the Resistance. Measurement on the test bed, non-fired engine operating temperature.
  2. Evaluation
    • The measured results are in K3/ESY4-Hes.

Special thanks to phila_dot for translating this section.

Personal tools