FB NWFW 6.20.0 Functional description
The function% NWFW calculates a factor which determines the position of the intake and exhaust camshafts for the weighting of the angle-angle diagrams in the functions
% ZWGRU and% MDBAS.
If no camshaft control is installed in the vehicle, the function should not be integrated.
Assignment of system constants for camshaft control
SY_NWS (A) Description
0 No camshaft control
1 switched camshaft control (2-point control)
2 continuous camshaft control
1 Switched camshaft control
If the camshaft is in the reference position, the factor is 0. When the camshaft is switched, the factor linearly decreases from 0 to 1 during the shifting time
Of the camshaft, the factor changes accordingly from 1 to 0.
2 Continuous camshaft control
The interpolation factor for the intake camshaft fwnwe is calculated by dividing the actual displacement angle of the camshaft and the desired displacement angles, the adjustment angles
The position of the camshaft relative to the reference position.
fwnwe =
?
wnwve_w
wnwvse_w
?
If the actual displacement angle of the camshaft is smaller than the desired displacement angle, the factor between the angle-of-incidence map for the camshaft setpoint position and the camshaft position is determined
Tilt angle map for the camshaft reference position interpolated. The reference position is dependent on the operating point (nmot, rl) of the motor, the reference position is fixed by
The controller (WNWREO or WNWRAS). If the actual displacement angle of the camshaft is within a band of the width DWFWNWE or DWFWNWA around the desired position
Of the camshaft, the factor is fixed to 1.0 ( "hysteresis"). As a result, small fluctuations of the camshaft position in the range of the desired position do not affect the
Interpolation factor, which addresses the angle-of-incidence map to the applied cam-shaft position. If the actual angle> target angle, the factor is limited to 1.0.
When the camshaft is in the reference position (i.e., in the late stop, B_wnws0e = true), the factor is described as zero.
If an error of the camshaft control is present (collective error B_enwse = true,% DNWSZF), the interpolation factor is set hard to zero and the calculation of the angle
Is carried out on the basis of the characteristic fields in the reference position. In the case of a central diagnosis control with inhibitor (SY_INHIBIT> 0), the switching of the angle calculation is found
But the release condition of the errors from the camshaft control instead (connection via FID) takes place.
For the exhaust camshaft, the interpolation factor fwnwa is determined from the respective camshaft displacement angles wnwva_a and wnwvsa_w.
Target displacement angle for calculating the interpolation factor
The camshaft control outputs a coordinated setpoint adjustment angle wnwvse_w or wnwvsa_w for the actuators, The set target positions for warm - up and
Heating the catalytic converter (see% NWSOLLE, resp.% NWSOLLA). Since the torque model has been tested on the engine test for a warm engine,
This displacement angle of the camshaft is not suitable for calculating the interpolation factor and must therefore be determined locally from the characteristic fields for the warm engine
(Hierarchy [wnwvse_calc] or [wnwvsa_calc]).
In this case, the camshaft position positions are always used for the homogeneous operating state; the homogeneous lean (HMM) mode is only applied to the characteristic map
KFWNWENHS or KFWNWANHS. Since no active calculation of the angle of inclination takes place in the layer mode (SCH), the desired positions for the homogeneous
APP NWFW 6.20.0 Application notes
The basic angle for the optimum angle of inclination zwopt in the% MDBAS and the basic point angle in the% ZWGRU is given for the basic specification
At the engine check, after the target positions of the camshafts have been set and the fill detection has been made. The camshafts are checked at the engine test
In each case in their desired and reference position, and the angle-angle diagrams are described from the torque optimization.
If the target positions of the camshafts are changed after the basic service has been carried out, then this reg- ulation strategy is followed by a subsequent specification of the torque model
With the angle angle fields.
1 Switched camshaft control
The time constants ZKWNWE and ZKWNWA correspond to the adjustment times of the camshaft adjuster from stop to stop.
ZKWNWE = 0.3s
ZKWNWA = 0.3s
2 Continuous camshaft control
If the actual adjustment angle wnwve_w is unstable in the stationary state, this can be achieved by a corresponding selection of the bandwidth DWFWNWE (or DWFWNWA for the exhaust camshaft)
Are compensated for by the setpoint adjustment angle. The factor is also fixed to 1.0 when, during the transition of the camshaft into the desired position, the actual displacement angle
Within the band by the desired displacement angle.
Neutral service:
DWFWNWE = 0.0 ◦KW
DWFWNWA = 0.0 ◦KW
First-time proposal:
DWFWNWE = 0.5 ◦KW
DWFWNWA = 0.5 ◦KW
The characteristic fields for the target angles of the inlet camshaft KFNWSE, KFWNWENHS and the exhaust camshaft KFNWSA, KFWNWANHS are only referenced and are
In the% NWSOLLE or% NWSOLLA. The reference positions for the intake camshaft WNWREO and that of the exhaust camshaft WNWRAS are in the% NWWUE
And also here only referenced. Labeling is not included in% NWFW.
